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THE CHEMICAL 
 
 WORKS 
 
 O F 
 
 CASPAR NEUMANN, M.D. 
 
 Profefior of Chemiftry at Berlin , F. R. S. &c. 
 
 Abridged and Methodized. 
 
 With large Additions, Containing the later Difcoveries and Improve- 
 ments made in Chemiftry and the Arts depending thereon, 
 
 By TV I L L I A M L E TV I S, M. 
 
 and Fellow of the Royal Society. 
 
 LONDON: 
 
 Printed for W. Johnston in Ludgate-Jlreet , G. Keith in Grace-church- 
 Jireet , A. Linde in Catherine-JlreeC , P. Davey and JB. Law in 
 Ave-maria-lane , T. F i e l d in Gheapfide , 1'. Caslok near 
 Stationers- Hall, and E. Duly in the Poultry. 
 
 l 
 
 MDCC LIX, 
 
1 
 
 . 
 
 
 c 
 
 y'.. i 
 
 ' r r • . 
 
 9 J.±. - ' - 
 
f | H E editor of Neumann s chemical ledhires publifhed at Zullichau , 
 f has prefixed to them a minute detail of the author’s life ; in 
 which we are informed of his being early received into the favour 
 of the King oi Pru/Jia-, of his travelling at his majefty’s expence, to get 
 acquainted with the chemical arts and bulinefies carried on in the diffe- 
 rent parts of Europe j of his being entertained, in this progrefs, by men 
 of the moft diftinguifhed abilities in the feveral branches of natural 
 knowlege; of his advancement to the public Profefibrfhip, the diredlion 
 of the royal elaboratory, and apotheca at Berlin. How much he 
 availed himfelf of thefe uncommon advantages, is obvious from his own 
 writings. 
 
 The works publifhed by Neumann himfelf confifi: chiefly of differta- 
 tions on particular fubjedtsj fome in Latin , and inferted in the tranf- 
 adtions of different lbcieties and academies, of which he was a member* 
 others in the German language and printed feparately. 
 
 In the Philofophical Tranfadtions of the Royal Society of London * 
 
 1. Difquijitio de camphor a , N° 399. 
 
 2. De experiment proba?idi fpiritum vini Gallici , perquam ujitato , fed 
 
 r ever a falfo & fallaci , N 0 391. 
 
 3. De falibus alkalino-fixis , N° 392. 
 
 4. De camphor a thy mi, N° 431. 
 
 5. De ambragryfea , N° 433. 
 
 In the Ephemerides , or Adi a phyfico-medica , Academice Caefarece 
 
 naturae curioforum. 
 
 1. De oleo diftillato formicarum aether eo, Vol. ii. 
 
 2. De albumine ovi fuccino Jimili , Vol. v. 
 
 In the Mifcellanea Berolinenjia * 
 
 1 . Meditationes in binas obfervatio?ies de aqua per putrefadlionem rubra , 
 vulgo pro tali in fanguinem ‘verfa habit a , Tom. iii- 
 
 A 2 
 
 2. Succinct a 
 
PREFACE. 
 
 2. SuccinBa relatio ex aBis Vomer anich de prodigio fanguinis in palude 
 
 vifo , ibid. 
 
 3. De prodigio fanguinis ex Pomerania nunciato , ibid. 
 
 4. Difquifitio de camphor a, ibid. 
 
 5. De experimento probandi fpiritum vini Gallicum , &c. ibid. 
 
 6. De Jpiritu urinojo caujhco , ibid. 
 
 7. Demonjiratio fyrapum violarum ad probanda liquida non Jujjicere , Tom. iv. 
 
 8. Rxamen correBionis oiei raparum , ibid. 
 
 9. De vi cau flic a & cornier fione falinm alkalino-fxorum aeri expojitorum in 
 falia neutra , Tom. v. 
 
 In the Commercium iiterarium phyfico-technicum medicum 'Norimbergenfe ; 
 
 Judicium & experiment a circa tinBuras coralliorum , Ann. 1735, 
 
 hebd. 1747 © 1748. 
 
 Publifhed feparately in German : 
 r. Einpropfung der pocken> Berlin, 1727. 
 
 2. De falibus alkalino-Jixis & camphor a, Berlin, 1727. 
 
 3. De fuccinOy opio , caryophjllis aromaticis, & cajloreo, Berlin, 1730. 
 
 4. Vom falpeter , fchwefef fpiefglafs, und eifen , Berlin, 1732. 
 
 5. Vom thee , coffee , und wein, Leipfic, 1735. 
 
 6. Difquifitio dc ambra gryfea , Drefden, 1736. 
 
 7. Vom gemeinen faltZy weinflem , falmiac , und der ameife, Leipfic, 1737. 
 
 The foregoing are all the writings of Neumann published in his life- 
 time. Since his death two copies of his chemical ledtures have appeared. 
 
 The hr ft con fills of notes taken down by one of his pupils, intermixed 
 with a number of incoherent compilations from different authors. This is 
 intitled Herr D. Cafpar Neumanns, gewefenen konigl. Preujffchen Hofraths 
 und profeforis publici chemice praBicre &c. PrreleBiones chemie ce , feu 
 c hernia medico-pharmaceutica experiment all s & rationales — heraufgegeben von 
 D. Johann Cirri jit an Zimmermann medicine e praBico in Schneeberg. Berlin, 
 1740. 2 vol. quarto — pages 1872, exclufive of prefaces and index — 
 Of this copy a feccnd edition has been publifhed, not materially 
 different, fo tar as I have obferved, from the former, though Neumanns 
 name is omitted in the title page, which in this new edition is as follows: 
 Allgemeine grundfitze der theo ret ifeh -praBifchen chemie , das iff griindlicher 
 und vollftandiger unterricht der chemie ; in weichem nicht nur iiberhaupt 
 cine griindliche anleitung zu alien theilen der chemie , fondern auch die — 
 vperationes und produBa — mit demonjlrationibus und experimentis- — gelehret 
 werden ; nebf beygefiigten medicinijchen , chirurgifchen , oeconomifcben , metal- 
 iurgifehen , &c. gebraucb und amoendung. Heraufgegeben von D. Johann 
 Chrifian Zimmermann . Drefden, 1755 — 2 vol. quarto — pages 1604. 
 
 The 
 
Preface. 
 
 The other copy is printed by the bookfellers of the orphan hof- 
 pital of Z ullichau (the city of Neumanns birth) and faid to be taken 
 from the original papers in the Author’s own hand-writing. This alfo 
 has had two impreflions ; one of which is an abridgement of the other, 
 from feven Volumes in Quarto into two, from upwards of 7000 pages 
 into 2560, under the following title : D. Cafpar Neumanns , chemahli - 
 gen konigl. PreuJJifchen Hojraths , proj efforts der chemie , &c. Chymia me- 
 dica, dogmatico-experimentalis , das ift , griindliche und mit experimenten 
 erweijene medicinijchen chymie. Z ullichau, 1756. 
 
 The editor of this abridgement obferves, that Neumanns writings 
 are extremely voluminous, and that therefore he has endeavoured to 
 reduce them, in fuch a manner as not to mutilate the fenfe, but 
 to give the whole of the procefles, experiments and obfervations in 
 the Author’s own words. So fcrupuloufly has this abridger fulfilled his 
 talk in this refpedt, that he has in general not ventured to contract 
 Neumanns diffufe manner of writing, or rather fpeaking to his audi- 
 ence. Much of the work is ftill taken up in a minute account of me- 
 dicinal preparations many of which are not ufed ; in the formal refu- 
 tation of theories and opinions not now received; in narratives and 
 difcufiions often foreign to the lubje£t and frequently frivolous in 
 themfelves. An account of the apparatus of the tea-table, and the 
 manner of making tea, fills a quarto page and a half of this abridge- 
 ment. 
 
 The general arrangement of the materials, exclufive of the minute 
 and trifling fubdivilions, is likewife very exceptionable. Thus the 
 chemical products or preparations *, which make the two firfi parts, 
 
 being 
 
 * The general distribution of the chemical preparations is as follows. 
 
 Part I. Of liquid preparations. 
 
 Sebt. I. Of waters. 
 
 Chap. X. Of Simple diStilied waters. 
 
 Chap. 2. Of compound diffilied waters. 
 Chap. 3. Of waters not distilled. 
 
 Sebt. II. Of fpirits : 
 
 Clafs I. Of inflammable fpirits. 
 
 Chap. I. Of Ample inflammable fpirits. 
 Chap. 2. Of fpirits prepared by Solution. 
 Chap. 3. Of Ample diltilled inflammable 
 fpirits. 
 
 Chap. 4. Of compound diltilled inflammable 
 fpirits. 
 
 Clafs II. Of faline fpirits. 
 
 Chap. x. Of urinous faline fpirits. 
 
 Chap. 2. Of vegetable acid fpirits. 
 
 Chap. 3. Of Ample mineral acid fpirits. 
 Chap. 4. Of compound mineral acid Spirits. 
 
 Clafs TIL Of oily faline fpirits. 
 
 Chap. 1. Of oily alkaline faline fpirits. 
 Chap. 2. Of oily acid Saline fpirits. 
 
 Chap. 3. Of compound oily faline fpirits. 
 Sedt. III. Of tinctures. 
 
 Clafs I. Of acid tindtures. 
 
 Chap. 1. Of watery acid tindtu/es. 
 
 Chap. 2. Of fpirituous acid tindtures. 
 
 Clafs IT. Of alkaline tindtures. 
 
 Chap. x. Of tindtures made with Axt 
 
P R - E F A C E. 
 
 being divided into liquid and folid; volatile fpirits are placed in the one 
 part, and the ialts in the other; though they ought naturally to come 
 
 together, 
 
 Chap. 2. Of tindtures made with volatile 
 alkali. 
 
 Oafs III. Of neutral tinctures. 
 
 Chap. x. Of thin neutral tindtures. 
 
 Chap. 2. Of thick neutral tindtures. 
 
 Clafs IV. Of alkaline oily tinctures. 
 Chap. 1. Of fimple alkaline oily tindtures. 
 Chap. 2. Of compound alkaline oily tinc- 
 tures. 
 
 Clafs V. Of oily or refinous tindtures. 
 Sed. IV. Of efl’ences. 
 
 Sect. V. Of elixirs. 
 
 Sed. VL Offaline folutions. 
 
 Sed. VII. Of oils. 
 
 Clafs I. Of Exprelfed oils. 
 
 Chap. i. Of fimple expreffed oils. 
 
 <Jhap. 2. Of boiled oils. 
 
 Clafs II. Of diftilled oils. 
 
 Chap. i. Of eflential oils. 
 
 Chap. 2. Of empyreumatic oils. 
 
 Sed. V ill. Of balfams. 
 
 Clafs I. Of natural balfams. 
 
 Clafs II. Of artificial balfams. 
 
 Chap. i. Of fpirituous balfams. 
 
 Chap. 2. Of oily balfams. 
 
 Chap. 3. Of falve-balfams. 
 
 Chap. 4. Of improper balfams. 
 
 Sed. ‘IX. Of extrads. 
 
 Clafs I. Of fimple extrads. - 
 Chap. 1. Of extrads called fuch. 
 
 Chap. 2. Of extrads not called fuch. 
 Chap. 3. Of fuch as ought not to be fa 
 called. 
 
 Clafs II. Of compound extrads. 
 Chap. x. Of pure compound extrads. 
 Chap. 2. Of impure compound extrads. 
 
 Part II. Of folid preparations. 
 
 Sed. I. Of falts. 
 
 Clafs I. Of alkaline- falts. 
 
 Chap. 1. Of volatile alkaline falts. 
 
 Chap. 2. Of fixt alkaline falts. 
 
 Clafs II. Of dry acid falts. 
 
 Chap. 1. Of volatile dry acid falts. 
 
 Chap. 2. Of fixt dry acid falts. 
 
 Clafs III. Of neutral falts. 
 
 Divifion I. Of faturated neutral falts. 
 Chap. 1. Of faturated volatile neutral falts. 
 
 Subdivifion 1 pure. 
 
 Subdivifion 2 more earthy. 
 
 Chap. 2. Of faturated fixt neutral falts. 
 Subdivifion I. Pure fixt neutral falts, in 
 the humid way. 
 
 1 vegetable. 
 
 2 mineral. 
 
 x. . . . with the acid of common 
 fait. 
 
 2. . . . with the acid of nitre. 
 
 3. . . . with the acid of vitriol. 
 Subdivifion II. more earthy fixt neutral 
 
 falts. 
 
 Subdivifion III. Fixt neutral falts in the 
 dry way. 
 
 1. . . . pure 
 
 2. . . . more earthy. 
 
 Divifion II. Of falfe neutral falts. 
 
 Chap. 1. . . . with two acids.' 
 
 Chap. 2. . . . impure. 
 
 Clafs IV. Metallic falts. 
 
 Divifion I. . . . volatile. 
 
 Divifion II. . . . more fixt. 
 
 Chap. I. Thofe made with vegetable acids. 
 Chap. 2. . . . with the nitrous acid. 
 
 Chap. 3. . . . with the vitriolic acid. 
 
 Chap. 4. . . . with different acids. 
 
 Sedt. II. Of earthy faline bodies. 
 Sect. III. Of fulphureous bodies. 
 Chap. 1. Of fublimed fulphureous bodies. 
 Chap. 2. Of fulphureous bodies not fub- 
 limed. 
 
 Sedt. IV. Of reguli. 
 
 Chap. j. Of fimple reguli. 
 
 Chap. 2. Of compound reguli. 
 
 Scdt.V . Of magifteries. 
 
 Clafs I. Of earthy magifteries. 
 
 Chap. 1. Thofe made from vegetables. 
 Chap. 2. . . . from animals. 
 
 Chap. 3. . . . from minerals. 
 
 Clafs II. Of metallic magifteries. 
 Chap. 1. Thofe made from im perfect me- 
 tals. 
 
 Chap. 2. . . . from imperfedt and perfedt 
 metals. 
 
 Chap. 3. . . . from perfedt metals. 
 
 Clafs 
 
PREFACE. 
 
 together, the fpirit being no other than a folution of the fait in water. 
 The chemical fubjeCts (which compofe the other three parts, under 
 the heacfs of vegetables, animals, and minerals) are ranged for the moll 
 part alphabetically ; each article being conlidered as one feparate whole, 
 and not as making part of a larger ftruCture. So fcrupuloully is the 
 order of Neumanns leCtures preferved, that where he deferred a fubjedt 
 to a future meeting, on account of his experiments upon it not having 
 been finilhed at the time when he ought to have fpoken of it, the 
 fubjedl continues mifplaced in all the editions. 
 
 Neumanns leCtures are a valuable magazine of chemical knowledge. 
 The Author, biafled by no theory, and attached to no opinions, has 
 enquired by experiment into the properties and ufes of the moil con- 
 fiderable natural and artificial produdtions, and the preparation of the 
 principal commodities which depend on chemillry ; and feems to have 
 candidly, and without referve, communicated all he difcovtred. 
 
 The merit of this work, fo much celebrated in Germany , and fo 
 little known here, engaged me to revife and abridge an Engl iff. h tranf- 
 lation, and to make fuch additions as appeared necefiary for fupplying 
 the deficiencies of the Author. 
 
 In regard to the original, the Zullichau edition has been followed ; 
 the abrupt tranfitions and mutilated ientences of the other fnewing 
 it to be of no authority. In the contraction, I found it necefiary to 
 proceed much further than the abridger of Zullichau has done, and 
 to take fome liberties not perhaps very common in performances of this 
 kind. It feemed requifite, not fo much to retrench the trivial and 
 redundant, as to extraCt and digefi: the ufeful matter. Accordingly I 
 have ventured to new mould the whole fabrick; and hope it will 
 appear, that all the valuable materials, fcattered through Neumann' s, 
 writings are collected and difpofed with propriety. 
 
 I have added by way of notes, the later difcoveries and improve- 
 ments made in chemifiry and the arts depending thereon. Much of this 
 
 Clafs III. Of fulphureous 'magifteries. 
 Clafs IV. Of refinous magifteries. 
 ■Clafs V. Of compound magifteries. 
 Clafs'VI. Of falfe magifteries. 
 
 Sedh VI. Of calces and croci. 
 Clafs I. Of animal calces. 
 
 Clafs II. Of mineral calces. 
 
 Chap- x. Of ample mineral calces. 
 Chap. 2. Of compound mineral calces. 
 SeCt. VII. Of glalTes. 
 
 Part III. contains the vegetable, Part IV. 
 the animal, and Part V. the mineral fubftan- 
 ces, examined by the Author. It is need- 
 lefs to infert the alphabetic catalogues of 
 them, as the table of contents of the pre- 
 fent work confifts of the fame articles, 
 ranged in a more fcientific method; a method 
 which Neumann himfelf has in different parts 
 of his writings pointed out. 
 
 part 
 
PREFACE. 
 
 part of the work is taken from the writings of others and not a little 
 from the diaries of my own elaboratory. 
 
 The index is to be confidered not barely as a table of references, 
 but as a fummary of the moft confiderable fails, which are there re- 
 prefented commonly in a new light. Several fails are mentioned in the 
 index which though deducible by analogy from the experiments in 
 the pages referred to, could not on that foundation alone be looked upon 
 as certain. There are even fo'me fails which have no reference at all, 
 and which are not mentioned in the book. Thus Acacia, an infpifiated 
 vegetable juice, prepared in Egypt, rarely met with among us, ufed in 
 medicine as a mild aftringent, is omitted by the author j and fuch an 
 article did not feem to be of importance enough to be introduced : But 
 on taking a review of the ajlringency of vegetables in the index, the light 
 in which this quality appeared there made Acacia worthy of notice; for 
 as among the vegetables examined by the author, the aftringency of 
 fome diffolves both in water and in fpirit, and that of others in fpirit 
 only ; Acacia is an inftance of a third kind of aftringent matter, dif- 
 folving in water only. 
 
 CON- 
 
o vv 
 
 CONTENTS. 
 
 The new articles are diftinguifhed by * Ailerifks. 
 
 PART I. 
 
 Chemical Hiftory of the Mineral Kingdom, 
 
 SECTION I. 
 
 Earths and Stones, 
 
 CLASS I, 
 
 Crystalline Stones. 
 
 F lint 
 
 Sand - 
 
 Cryftal - 
 * Gems - 
 
 page 
 
 2 
 
 4 
 
 6 
 
 6 
 
 CLASS II. 
 
 Calcareous Earths and Stones 1 
 
 Chalk 
 Olteocolla 
 Limeftone 
 Quicklime 
 
 8 
 
 C LASS III. 
 
 .Lapis Specularis ' - 
 
 * Gy plum Striatum 
 
 * Pefu'ntfe 
 Seienites 
 Bolcgnian Stone 
 
 n ■■ 
 
 CLASS IV. 
 Argillaceous Earths 
 and S t o n e s. 
 
 page 
 
 * Clays - - - * , 
 
 Boles - jb. 
 
 * Loams - - _ 22 
 
 * Kaolin - - - - 18 
 
 Tripoli - >5 
 
 * Steatites - 26 
 
 Lapis nephriticus - - ib. 
 
 * Ochres - - - 80 
 
 1 1 
 
 * Aluminous earth 
 
 185 
 
 1 4 
 
 ib . 
 
 CLASS 
 
 V. 
 
 T A LKY -E A R T H S 07 
 
 Stones. 
 
 
 Venice Talk 
 
 27 
 
 29 
 
 ONE s. 
 
 Solar Talk 
 
 
 Amianthus 
 
 8° 
 
 18 
 
 * Black Lead 
 
 22 
 
 ' ib . 
 
 bill 
 
 and Stones. 
 
 ib . 
 
 Anomalous Earths , 
 
 1 9 
 
 Pumice 
 
 30 
 
 ib. 
 
 MagnGia 
 
 1 90 
 
 
 a 
 
 SEC T. 
 

 c 
 
 O N 
 
 T 
 
 
 
 S E 
 
 c 
 
 
 
 Metal 
 
 , L I 
 
 
 C L A S 
 
 S I. 
 
 i 
 
 P; 
 
 erfect Metals. 
 
 
 
 
 
 page 
 
 Gold 
 
 - 
 
 .. 
 
 32 
 
 * Plarina 
 
 - 
 
 - 
 
 43 
 
 Silver 
 
 - 
 
 - 
 
 46 
 
 
 C L A S 
 
 S II. 
 
 
 I M P 
 
 ERFECT 
 
 Metals. 
 
 
 Lead 
 
 . 
 
 - 
 
 54 
 
 Copper 
 
 - 
 
 - 
 
 61 
 
 Iron 
 
 - 
 
 - 
 
 68 
 
 Tin 
 
 ■ 
 
 - 
 
 85 
 
 
 
 S E 
 
 C 
 
 
 
 Mine 
 
 R A 
 
 Adds and Alcalies 
 
 in general. 
 
 and 
 
 tjjeir combination 
 
 - - 
 
 159 
 
 
 C L A S S I. 
 
 
 V 1 
 
 T R I O L I 
 
 c Acid. 
 
 
 Pur$ Vitriolic Acid - - 160 
 
 Combination with Phlogiilon 163 
 
 Sulphur - - - 165 
 
 Combination with Metals - - 172 
 
 Pyritre - 171 
 
 Vitriols - - - 173 
 
 Green Vitriol - - 179 
 
 Blue Vitriol - - - 182 
 
 White Vitriol - 183 
 
 Combination with Earths - 184 
 
 Alum - - - - 185 
 
 Bitter purging Salt - - 189 
 
 Selenites - - - 184 
 
 Combination with Alcalies - 190 
 
 Vitriolated tartar - 192 
 
 Glaubers Salt - - 193 
 
 Secret Sal ammoniac: - - 194 
 
 5 
 
 ENTS. 
 
 T. II. 
 
 c Bodies. 
 
 CLASS HI. 
 
 Semi metals. 
 
 page 
 
 Mercury - - - - 91 
 
 Bifmuth - - 106 
 
 Zinc - - - - 1 15 
 
 Regulus of Antimony - - 128 
 
 Arlenic - - - -140 
 
 * Cobalt - - - - 152 
 
 * Nickel - 153 
 
 * * * 
 
 to each of which is added its mojl con - 
 fiderable ores and mineral forms. 
 
 T. III. 
 
 . Salts. 
 
 C L A S S ■ II. 
 Nitrous Acid. 
 
 Pure Nitrous Acid - - 195 
 
 Combination with Phlogifton - ib . 
 Combination with Metals - 196 
 
 Combination with Earths - 9,17 
 
 Combination with Alcalies - 197 
 
 Nitre - ib. 
 
 Nitrum Flammans - - ib. 
 
 CLASS III. 
 Marine Acid. 
 
 Pure Marine Acid - - 207 
 
 Combination with Metals - 208 
 
 Combination with Earths - 225 
 
 Sal ammoniacum fixum - ib. 
 Combination with Alcalies - 209 
 
 Common Salt - - ib. 
 
 Regenerated common Salt 215 
 Sal ammoniac - - 216 
 
 Anomalous Salts. 
 Borax - 226 
 
 Salt of Amber - 236 
 
 SECT. 
 
CONTENTS, 
 
 SECT, IV. 
 
 Bituminous Substances, 
 
 P a g e . i»»ge 
 
 Naphtha 230 Ambergris - 239 
 
 Petroleum - - - ib. White marine bitumen - - 242 
 
 Barbadoes tar - - - 231 Afphaltum - ib. 
 
 Turf - - - - - 231 Pitcoal * 244 
 
 Amber - 232 Jet ----- - 245 
 
 SECT. V. 
 
 Waters. 
 
 Common waters - ■ 247 Brine fp rings - 25s: 
 
 Sea water - ~ - 249 Medicinal waters - - - 253 
 
 PART II. 
 
 Chemical Hijlory of the Vegetable Kingdom, 
 
 SECTION I. 
 
 O/Vege tables in general . 
 
 C HEMICAL Structure of 3. Efiential Oils - - 268 
 
 Vegetables - 260 4. Camphors - - 277 
 
 Native principles of Vegetables 264 5. Exprefied Oils - ib. 
 
 1. Gums - - , - - - 267 6. Elfential Salts - 278 
 
 2. Refins - - - - - ib. Artificial principles of Vegetables 280 
 
 SECT. II. 
 
 Vegetable Juices. 
 
 Balfam of Copaiba - - - - 285 
 
 CLASS I. Balfam of Peru ib. 
 
 Q u M s> Turpentines - .... 2 86 
 
 Tar and Pitch - - 288 
 
 Gum tragacanth - - - 281 Storax - - - - - 290 
 
 ** Gum Arabic - - 282 Liquid Storax - - - - - 291 
 
 * Gum Senegal - ib. * Liquid amber - 292 
 
 Benzoine - ib. 
 
 CLASS II. T acamahacca 294 
 
 Resin s. Ladanum ------ 295 
 
 Elemi - --296 
 
 Opobalfam ------ 2S3 Anime - ------ ib. 
 
 Balfam of Tolu - - - - 284 Maftich ------- 297 
 
 a 2 Guaiacum 
 
C G N T 
 
 page 
 
 Guaiacum ------ 298 
 
 * Copal ------- 299 
 
 * Dragon’s blood - ib. 
 
 CLASS III. 
 Gummy-Resins. 
 
 Gamboge - “ - - - - - 300 
 
 Euphorbium - - - " - - 301 
 
 Scammony ------ 303 
 
 Aloes - ’ 305 
 
 Opium - ----- 307 
 
 Gum Ilederae ----- 311 
 
 Sarcocolla ------ ib. 
 
 Afafetida - - - - - - 3*2 
 
 Ammoniacum - - - - - ib. 
 
 Bdellium - - 3 1 3 
 
 Galbanum - - - - - ib. 
 
 Olibanum - - - - - 315 
 
 Opopanax - - - - ib. 
 
 Sagapenum - - - - - - 316 
 
 Myrrh - ------ ib. 
 
 Terra Japonica - - - - - 317 
 
 CLASS IV. 
 
 Camphors - -- -- - 318 
 
 ENTS. 
 
 C L A S S V. 
 
 Expressed Oils. 
 
 Oft Olive - - - . 
 
 page 
 
 • - - 3 22 
 
 Oil of Ben - 
 
 - - - 3 2 3 
 
 Perfumed oils - - - 
 
 - - - ib. 
 
 Oil of Bays - - - 
 
 - - - 3 2 4 
 
 Palm oil, Gfc. - _ - 
 
 - - - ib. 
 
 CLASS 
 
 VI. 
 
 Sweet Saline 
 
 J U I C E S. 
 
 Manna - - - - - 
 
 ■ - ■ 3 2 4 
 
 Sugar - - - - - 
 
 * “ 3 2 7 
 
 CLASS 
 
 VII. 
 
 Juices collected from Vegetables 
 
 by Infects. 
 
 
 Honey - - - - 
 
 - ‘ ‘ 33 ° 
 
 Bee-glue - - 
 
 ~ ‘ 33 2 
 
 Wax 
 
 
 Lacca 
 
 - * 333 
 
 SECT. III. 
 
 Plants and their parts in Subftance. 
 
 Pellitory ------- 342 
 
 CLASS L Stavefacre ------ 343 
 
 Gummy Vegetables. Grana cnidia ----- 344 
 
 Cocculus Indus - 345 
 
 'Marfhmallow ----- 33 5 Nux vomica ----- 345 
 
 Comfry ------- 336 Ignatius’s bean - - - - - ib. 
 
 Fenugreek - - - - - - ib. White hellebore - - - 347 
 
 Black hellebore ----- - 348 
 
 CLASS II. Agaric ------- 349 
 
 Resinous Vegetables. Colocynth - -- -- - 351 
 
 Bryony - - - - - ib. 
 
 Red Saunders - - - - - 33 7 Jalap - - - - - - - 352 
 
 * Alkanet ------- ib. Mattalifta ------ 353 
 
 Peruvian bark ----- 338 Turbith ------- 354 
 
 Guaiacum ------ 340 Hermodadtyl ■= - - - - ib. 
 
 Burnet Taxifrage - - - - 341 
 
 CLASS 
 
CONTENTS. 
 
 CLASS III. 
 
 Gummy-resino 
 
 Vegetables. 
 
 Tobacco - - - - 
 
 Arnica ------- 
 
 Ipecacoanha 
 
 Afarum -------- 
 
 Sena ------- 
 
 Rhubarb - ------ 
 
 Monks rhubarb - - - - - 
 
 Rhapontic - 
 Arnica Schweedenfis 
 Tormentil ------ 
 
 Galls ^ - 
 
 Gentian ------- 
 
 White dittany - - - - - 
 
 Leffer centuary - - - - 
 
 Carduus - - 
 
 Horehound ------ 
 
 Worm-feed - 
 
 Contrayerva 
 
 Vincetoxicum - - - - 
 
 Valerian - - - - - - 
 
 Peony ------- 
 
 Scrophularia - - 
 
 Polypody - - 
 
 Doronicum - - - - 
 
 Iris - -- 
 
 Hypericum - - - - - 
 
 Golden Stcechas - - - - 
 
 Tea - ------ 
 
 Coffee ------- 
 
 Veronica - - - - 
 
 Lungwort - 
 
 Pareira brava - - - 
 
 China root - 
 
 Sarfaparilla - 
 
 Sopewort - 
 
 Burdock - 
 
 u s 
 page 
 
 355 
 
 35 6 
 
 ■ 351 
 35* 
 
 ib. 
 
 359 
 
 3 6r 
 
 ib. 
 
 ib. 
 
 362 
 
 - ib. 
 
 3 6 3 
 3 6 4 
 
 ■ 3 6 5 
 
 - ib. 
 
 366 
 
 - ib. 
 
 3 6 7 
 
 ib. 
 
 3 6 9 
 
 370 
 ib. 
 ib. 
 
 37 1 
 
 - ib. 
 
 31 2 
 ib. 
 
 31 * 
 
 379 
 
 380 
 
 ib. 
 
 2 8 1 
 382 
 
 ■ 3*3 
 
 ib. 
 
 * Brazil wood 
 
 * Madder - 
 
 page 
 
 386 
 
 387 
 
 CLASS IV. 
 Unctuous vegetable 
 Substances. 
 
 Almonds 
 
 Linfeed, 
 
 388 
 2 77 
 
 CLASS V. 
 
 Vegetables, whofe prevailing 
 principle is an Ejfential oil. 
 
 Horferadifh - 
 Garlic - 
 Onions - 
 Imperatoria 
 Angelica - 
 
 Anifeed - 
 Stellated anife - 
 Smallage - - 
 
 Cicuta aquatica 
 Fennel - 
 Chervil - 
 
 Betony - 
 
 DidLmnus creticus 
 Rofemary - 
 Orange ilovveis 
 Saffron - 
 
 Cardamom feeds - 
 Cinnamon - 
 Cafia lignea - 
 Nutmeg - - - 
 
 Mace - 
 
 390 
 
 39 r 
 
 39 2 
 
 ib. 
 
 393 
 
 ib. 
 
 394 
 
 395 
 ib. 
 
 397 
 
 39 8 
 ib. 
 
 399 
 
 ib. 
 
 400 
 ib. 
 
 401 
 
 402 
 
 403 
 ib. 
 
 40 5 
 
 C L A S S VI. 
 
 V ege tables, whofe qualities de- 
 pend partly on an efjential oil , and 
 partly on a gummy -refinous matter. 
 
 Turmeric 
 
 384 
 
 Carlina 
 
 405 
 
 Fuftic 
 
 ib. 
 
 Nigelia 
 
 406 
 
 Yellow-wood 
 
 ib. 
 
 Birthwort 
 
 - ib. 
 
 Nephritic wood 
 
 3*5 
 
 Wormwood 
 
 40 7 
 
 Logwood - 
 
 - ib. 
 
 Camomile - 
 
 408 
 
 Orange 
 
CONTENT Si 
 
 Orange peel 
 Lemon peel - 
 Milfoil - 
 Pimpinella nigra 
 Caiamus aromaticus 
 Cyperus ~ 
 
 Zedoary - 
 Ginger - 
 
 Galangal - . - 
 
 Cloves - 
 
 Antophyllus - 
 Pimento - 
 Pepper - 
 Cubebs - 
 Grains of Paradile 
 Rhodium - - 
 
 Yellow Saunders 
 Safiafras 
 Elecampane 
 Spikenard - 
 French lavender - 
 Hvffop - 
 Feverfew - 
 Rue - 
 
 Scordium - - - 
 
 CLASS VII. 
 
 Saline Vegetables. 
 
 page 
 
 408 
 ib. 
 
 409 
 ib. 
 
 410 
 ib. 
 
 411 
 ib. 
 
 412 
 ib. 
 
 414 
 
 ib. 
 
 41 6 
 
 417 
 ib. 
 ib. 
 
 418 
 ib. 
 
 420 
 ib. 
 
 42 1 
 ib. 
 ib. 
 
 422 
 ib. 
 
 Lemon juice 
 Orange juice, &c. 
 
 423 
 
 ib. 
 
 Sorrel 
 
 Cafia fiftularis 
 Carob 
 Liquorice 
 Mullein 
 
 page 
 
 423 
 
 424 
 ib. 
 
 425 
 
 426 
 
 C L A S S VIII. 
 Anomalous Vegetables. 
 
 Arum - 
 Lycopodium - 
 Cork 
 
 Cotton - - - 
 
 * Linen, - 
 
 Vegetable Colour 
 
 * Coloured flowers 
 
 * Blue - 
 
 * Red - 
 
 * Yellow - 
 
 * White - - - 
 
 * Coloured fruits - 
 
 * Buckthorn berries - 
 
 * Turnfol - 
 
 * Annotto - 
 
 * Colours of leaves 
 
 * Indigo - 
 
 * Woad - 
 
 * Archil - 
 
 426 
 
 427 
 ib. 
 
 428 
 ib. 
 
 s. 
 
 43 ° 
 
 ib. 
 
 431 
 ib. 
 
 432 
 ib. 
 
 433 
 ib. 
 ib. 
 
 434 
 
 435 
 
 437 
 
 43* 
 
 SECT. IV. 
 
 Artificial Productions from Vegetables. 
 
 CLASS I. 
 
 Preclusions from Vegetables by 
 Fermentation. 
 
 Of fermentation in general - 440 
 
 Wines - 441 
 
 Malt liquors - 448 
 
 Inflammable fpirits - - 449 
 
 Tartar - - - -456 
 
 Vinegar - - - - 458 
 
 CLASS II. 
 
 Productions from Vegetables by Fire; 
 
 General refolution by fire - 462 
 
 Empyreumatic oils - - 464 
 
 Soot - - - 465 
 
 * Charcoal - 464 
 
 Fixt alcaline falts - - 4 66 
 
 * Incinerated earth - - 478 
 
 PART 
 
CONTENTS. 
 
 PART III. 
 
 Chemical Hiftory of the Animal Kingdom. 
 
 SECTION I. 
 
 Of animal Subftances in general 
 
 - 
 
 page 
 
 48 1 
 
 SEC 
 
 T. II. 
 
 
 Products from Animal Subftances by Fir 
 
 E. 
 
 Volatile falts and fpirits - 485 
 
 Latent animal acid - - 491 
 
 Animal Oils 
 Animal earths 
 
 492 
 - 493 
 
 SEC 
 
 T. III. 
 
 
 I N S' I 
 
 £ C T S. 
 
 
 Cantharides ... 494 
 
 Ants - 497 
 
 Earthworms “ - - - 500 
 
 Millepedes - 502 
 
 Cochineal - 
 
 * Kermes 
 
 * Coccus Polonicus 
 
 * Purple fifh 
 
 - 5°3 
 
 508 
 
 - - - 509 
 
 • 5 IQ 
 
 SEC 
 
 T. IV. 
 
 
 Horny parts of Animals. 
 
 
 Rhinoceros’s horn - - 51 1 
 
 Cowshorn - - - - 512 
 
 Tortoife fhell - - - 513 
 
 Elks hoof - 
 Ox hoof - 
 Whale-bone 
 
 - 5 r 4 
 
 5 1 5 
 
 516 
 
 SEC 
 
 T. V. 
 
 
 Bony parts of Animals. 
 
 
 Bones - - - - 516 
 
 Artificial Turcois - - - 518 
 
 Ox bone - - - 519 
 
 Hartfhorn - 520 
 
 Cranium humanum - - 521 
 
 Boars tusk - ib. 
 
 Tooth of the hippopotamus - 522 
 
 Tooth of the fea horfe - - 523 
 
 Ivory 
 
 Carp (lone - 
 Perch (tone 
 Jaw of the pike 
 Lapis manati 
 Talus leporis 
 Unicorns horn 
 
 524 
 
 - 525 
 
 526 
 ib. 
 
 5 2 7 
 
 - 5 2y 
 
 ib. 
 
 SEC 
 
 T. VI. 
 
 
 Earthy parts of Animals. 
 
 
 CLASS I. 
 
 Earthy Substances not 
 burning into Quicklime . 
 
 Pearls - - - * 529 
 
 Bezoar 
 
 * Human calculus 
 Crabs eyes - 
 Cuttle bone 
 
 - 532 
 
 533 
 
 “ 537 
 
 539 
 
 CLASS 
 
 Pearls 
 
 CLASS 
 
CONTENTS. 
 
 CLASS II. 
 
 Earths burning into 
 
 Quicklime . 
 page 
 
 Mufcle fhells 
 
 540 
 
 Oyfter fhells 
 
 541. 
 
 Mother of pearl 
 
 - ib . 
 
 Crabs claws 
 
 542 
 
 Egg fhells - 
 
 r ib. 
 
 SEC 
 
 Hairs, Feathers, Ur. 
 
 - 
 
 CLASS III. 
 
 Anomalous earthy Substances." 
 
 page 
 
 Coral 
 Coralline 
 Sponge - 
 
 T. VII. 
 
 SECT. VIII. 
 
 Fleshy parts p/'Animals. 
 
 544 
 
 54 ^ 
 
 ib . 
 
 548 
 
 Flefh - - - - 55° Fifh 55 1 
 
 Blood - - - - 55 1 Mummy ib. 
 
 SECT. IX. 
 
 Gelatinous Animal Substances. 
 
 Gel lies - 552 Ichthyocolla 553 
 
 Glue - - - - 553 E SS S 554 
 
 SECT. X. 
 
 Unctuous parts of Animals. 
 
 Fats 
 
 - 
 
 558 
 
 Odoriferous Substan 
 
 
 Marrow - 
 
 - 
 
 S ' 60 
 
 C E S. 
 
 Brains - 
 
 - 
 
 - ib. 
 
 Civet - 
 
 562 
 
 Spermaceti 
 
 - 
 
 ib. 
 
 Musk - 
 
 563 
 
 Train oil 
 
 
 562 
 
 Caftor - 
 
 5°5 
 
 
 S 
 
 E C 
 
 T. XL 
 
 
 Animal Gall 
 
 - 
 
 - 
 
 
 
 566 
 
 
 S 
 
 E C 
 
 T. XII. 
 
 
 Milk 
 
 - 
 
 - 
 
 - 
 
 5% 
 
 
 S 
 
 E C 
 
 T. XIII. 
 
 
 A N I 
 
 M A 
 
 L E; 
 
 XCREMENTS. 
 
 
 Urine - 
 
 - 
 
 574 
 
 Alvine feces - 
 
 .^85 
 
 * Microeofmic fait - 
 
 
 575 
 
 Album grascum - 
 
 ib- 
 
 Phofphorus *- 
 
 
 579 
 
 
 
 E 
 
 R 
 
 R 
 
 A T A. 
 
 
 Page iS. vote, column 2. line 10. for flints read fritt. P. 22 n. col. i, A 6. from the bottom, 
 for feem read l'eems. P. 44. col. 2. lin. ult. for lefs read often greater. P. 65. 1 . 6. in its pure. 
 Jlate Jhould come after copper, not after quickfllver. P. 66. note, col. 2. 1 . 1. for part read parts. 
 P. 85. A 1 6. for attra&iofl read alteration. P. 169. note, col. 1. / 7. dele bifmuth. P. 176. 
 note , col. 2, A 7. after upon evaporating the purging mineral waters. P . 181. A 6. yrij.w the* 
 bottom, for vitriolic vitriol, P. 26.1. note (b), All. for mild read wild. P. 274. note, col. 2. 
 L 20. for anima read animal. P . 450. note, lajl line , for abohol read alcohol. 
 
lauBfiCk. j * : M : k.j^^k.j^^kj^^k,jrf^k.j^^k.j^- 
 
 PART I. 
 
 CHEMICAL HISTORY 
 
 OF THE 
 
 MINERAL KINGDOM. 
 
 SECTION I. 
 
 EARTHS and STONES. 
 
 ARTHS and Stones are confidered by naturalids as two dif-EARTHS. 
 
 tin<£b clafies of bodies : And each of them arranged, from certain v v~ — ; 
 
 obvious appearances, as colour, confidence, external figure, tex- Common di- 
 ture, idc. into numerous fubdivifions. Achemical examination has Earths°and 
 difcovered, that many of thefe apparently very different bodies Stones, fuper- 
 are, in their effential properties, the fame-, and that many of thofe, which areficial. 
 apparently fimilar, are efientially very different. Thus the fofted Chalk, the 
 hardeft Marbles, the mod pellucid Spars, are found to be at bottom one and the 
 fame Earth : fire reduces them all intoQuick-lime ; Acids difiolve, and form with 
 them indidinguifhable compounds. And on the other hand, the Talcs and 
 Gypfums, though fome of them are externally id much alike as to have often 
 been confounded with one another and called by the fame name, confid of 
 Earths entirely didindl: one refids the mod vehement fires, whild the other, 
 in a very moderate heat,, feems to liquefy and boil, and changes into the fub- 
 dance called Plader-of-Paris : the latter, burnt in contact with the fuel, dif- 
 folves readily in Acids, whild the former, treated in the fame manner, con- 
 tinues to refid every kind of humid Menjlruum, 
 
 B Stahl., 
 
2 Earths and Stones. 
 
 E a rt hs. Stahl, difregarding fuperficial and ineffential charadlers, formed a diftribution 
 of Earths and Stones from their chemical properties. He divides them all into 
 two claffes, Yitrefcible and Calcareous ; the firft comprehending thole which 
 have a greater or lefs degree of tranfparency, and aredifpofed to vitrify in the 
 fire ; the other, fuch as are opake, become brittle or hard in the fire, and refill 
 vitrification. This arrangement, though an ufeful one, is in feveral refpedb 
 exceptionable, and requires further diftindtions and limitations. 
 
 Chemical dif- “ Experiments have fliewn, that there are four kinds of Mineral Earths, 
 tribution of diftindl from one another, the Cryflalline, Calcareous, Argillaceous and 
 Talky ; to which may be added a fifth fort of earthy concrete, the Gypfeous. 
 All the earthy and (tony bodies of the Mineral Kingdom, that have been che- 
 mically examined, are found to confifl of thefe, not often in their feparate 
 or pure flate, but for the mofl part varioufly blended together, and combined 
 with metallic or other heterogeneous matters. 
 
 Each of the fimple Earths, and the gypfeous Concrete, fuflains, by itfelf, 
 the mofl vehement degrees of Fire that art has hitherto been able to excite, with- 
 out fhewing any difpofition to melt or foften : Two or more of them, mixed 
 together, oftentimes melt in a moderate fire, and form a truly vitreous com- 
 pound. This remarkable property is a proof of the intrinfic diffimilarity of the 
 Earths ; for we cannot fuppofe that an unfufible fubflance would be brought 
 into fufion by the bare addition of its like. It follows alfo, that fufibility, 
 though ufually looked upon as a chara&er of one particular fpecies of fimple 
 Earth, is really a character of compofitions of Earths, and belongs equally to 
 
 a great variety of combinations of them. The fimple Earths are brought 
 
 into fufion by the addition of certain Salts and metallic calces : and fuch mix- 
 tures of Earths, as do not melt by themfelves, melt with a lefs proportion of 
 thefe fluxes than the ingredients feparately would require. The different Earths 
 differ remarkably in their relation to thefe bodies ; fome entirely refilling 
 
 thofe which are mofl powerful fluxes for others It may be proper to ob- 
 
 ferve, that the refult of the fufion of Earths, by whatever means effedled, is 
 conflantly a vitreous matter. Some metallic calces and glaffes would not 
 eafily be diflinguifhable from thofe of Earths, if the metallic ones were not 
 revivable by inflammable fluxes into their proper metallic flate.” 
 
 i 
 
 CLASS L Crystalline Stones. 
 
 Stony bodies of great hardnefs , capable of Jlriking fire with Steel ; — by 
 vehement heat and extinction in water , becoming brittle , friable , or 
 powdery: — not aCied upon in the leaf by Acids , either in their natu- 
 ral fiate or when calcined. 
 
 I. FLINT. 
 
 Flint. HpME Flint is a femitranfparent flone, generally covered with an opake 
 jf_ white cruft. Its colour varies, from a pale brownifh grey, to a dark 
 Natural Hif- brownifh black : its texture is always fmooth and uniform j its figure irre- 
 eo T“ gular. Thofe found in the beds of rivers, or thrown out upon the fea-fhores, 
 
 5 are ' 
 
O 
 
 Earths and Stones. 
 
 are commonly the moft pure from heterogeneous admixtures: the Land-Flints Flint, 
 have often fpecks orftreaks of areddifh ferrugineous matter, difcoverable chiefly G— 
 after they have been burnt or calcined. In fome there are veins of native 
 gold : One of the moft curious fpecitnens of this kind is in the cabinet of 
 his Pruffian Majefty. 
 
 The fparks which ilTue from the collifion of Flint and Steel, collected Sparks from 
 upon Paper and viewed with a microfcope, appear to be globules of vitrified Hint and 
 matter: A chemical examination difcovers that they contain more of the^j eeJ exanuu ~ 
 Iron than of the Flint, changed into a kind of glaffy Scoria (a ). — Two Flints 
 {truck againft one another, project no vifible fpark ; nor do the fragments 
 broke off feem to have fuffered any change: But the Stones themfelves 
 appear, in the dark, luminous; fome throughout the whole mafs, others only Phofphorus. 
 on the fide ftruck upon. The greater number of Flints I have examined is of 
 this laft kind. 
 
 Boerhaave relates,, that Flint, placed in the focus of Villette’s burning fpe- Flint at a 
 culum, was inftantly converted into glafs. 1 have had no opportunity of burning glafs, 
 trying that inftrument ; but have expofcd Flint to the adlion of the large 
 burning; lens of Tfchirnhaus, without being able to produce any fuch effect. 
 
 Though Flint, however, by itfelf, abfolutely refills that moft vehement heat, Melted with 
 and Quick-lime by itfelf equally refills it; yet a mixture of the two runs with Lirae - 
 eafe into glafs (c). 
 
 Powdered Flint, mingled with a due proportion of fixt Alcaline Salt Vitrification 
 melts eafiiy in rhe common furnaces, and forms the bafis of the fine white vvit h Salts, 
 cryftalline kinds of Glafs, and of the compofitions for imitating precious 
 {tones fib). Kunckel recommends the Sea-flints, as yielding a finer Glafs, 
 and requiring lefs Salt, than thofe found on the land : Others object to the 
 
 marine 
 
 (a) Sparks from Flint and Steel.'] It does 
 not appear that the Steel is here really vi- 
 trified, or that the heat produced is fo in- 
 tenfe as has been generally fuppofed. A- 
 mong the particles of metal abraded by 
 the Flint, there are indeed fome globular 
 ones which have evidently been melted : 
 but the magnet ftill attracts them ; a mark 
 that they are not fcorified, but continue 
 perfectly metallic. The fufion of fmall 
 moleculae of Steel doe9 not require any 
 very extraordinary heat : if fine Steel-wire 
 be held barely in the flame of a candle, the 
 end will melt, and form a little ball like 
 thofe obtained in the experiment of ftriking 
 fire with Flint. 
 
 (b) Vitrification of Flint.] Of all the fa- 
 line matters that have been tried in compo- 
 fition with Flint, fixt alcalies moft effectu- 
 ally promote its vitrification : two parts of 
 the Alcali and three of Flint, urged with 
 a ftrong fire, form a perfect glafs. Borax, 
 
 by vehemence of heat, may be made to 
 vitrify twice its weight, and even more ; 
 but the compound fcarcely proves tranfpa- 
 rent, unlefs the Borax be equal in quan- 
 tity to the Flint : a fmall addition of Alca- 
 line Salt to this mixture promotes both the 
 fufion and tranfparency : the glaffes made 
 with Borax, or with Borax and a little 
 Alcali, prove rather harder than thofe with 
 the Alcaline Salt alone — Common Salt, 
 Sal mirabile and Sandiver, are remarkably 
 indifpofed to vitrify with Flint, though 
 taken even in twice or thrice the quantity 
 of the Stone : nor do they, in any proportF 
 ons, form with it a pellucid glafs. 
 
 (c) Vitrification of Flint with other earths. ]: 
 Powdered Flint has been mixed in different 
 proportions both with Quick-lime and with 
 Earths of each of the other claffes, and 
 urged with the moft intenfe fires procur- 
 able in the common furnaces, without 
 fhewing any difpofition to melt : but thefe 
 l. z. mixtures. 
 
4 
 
 Earths and Stones. 
 
 Flint, marine Flints, that they make the Glafs brittle and apt to crack. Thofe 
 w — —y which exhibit red veins when calcined, fhould either be rejected, or freed from 
 that extraneous matter, which would give a tinge to the Glafs: This may be 
 effected by walking the powder with Spirit of Vitriol or Aqua Regis, and after- 
 wards edulcorating it with water. Such as have been pulverifed in an iron 
 mortar fhould likewife be purified by the fame means from the ferrugineous 
 particles they may have abraded from the inftrument, before they are employed 
 in the compofition of any curious Glafs. White Sand is often fubflituted in 
 the place of Flint, and does net confiderably differ from it in quality (d). 
 Calces of Lead af£ commonly added, for the colourlefs as well as coloured 
 glaffes, to promote the vitrification. 
 
 Diffolved in Though a moderate proportion of fixt Alcaline Salt unites with Flint, in 
 Alealies. the fi re , into a perfect glafs, which is not diflbluble in any liquor, and 
 difeovers no mark of a faline nature •, a fomewhat larger proportion of the 
 Alcali changes the Flint itfelf into an apparently faline form. If powdered 
 Flint be mixed with thrice, twice, or even equal its weight of fixt Alcaline 
 Salt, and the mixture melted in a crucible ; the mafs, though it has a vitri- 
 ous appearance, proves in tafte faline and fiery, like the Alcali itfelf; and 
 on being expofed to the air, runs in a little time, Flint and all, into a colour- 
 lefs tranfparent liquor, called Liquor Jilicum , ox Oleum filicis per deliquium (e). 
 Coagulation This liquor, on being mixed with mineral Acids, particularly the Vitri- 
 ©f Liquids. 0 lic, inftead of effervelcing and uniformly mingling with them, as mere 
 Alcaline Liquors do, grows inftantly thick, and in fome degree folid ; as if 
 the diffolved Flint was going to refume its original confiltence. It coagu- 
 lates 
 
 mixtures are brought into fufion by a much 
 lefs proportion of Salt than the ingredients 
 fingly would require. Though Alealies are 
 the mod powerful flux for Flint by itfelf, 
 Borax is found mod effectually to vitrify the 
 compounds. 
 
 (d) Sand.) Though the fine white Sands 
 appear to the eye to be purer than Flint, 
 they fcarcely afford fo clear a glafs : the 
 difference is the mod perceptible when 
 each of them is melted with a fomewhat 
 fmaller proportion of Alcali than is fuffi- 
 cient to bring them to their full tranfpa- 
 rency. Pott relates, that on melting Sa-nd 
 with half its weight of Nitre, he obtained 
 a glafs of a purple colour ; probably from 
 fome metallic matter, of which moil Sands 
 participate in a greater or lefs degree. 
 
 The red and yellow Sands are mani- 
 feftly impregnated with a ferrugineous calx. 
 They contain alfo a minute portion of 
 Gold ; which is feparable from them in the 
 way of affay, though no method has hither- 
 to been found of extracting it to advantage 
 in the larger works. Cramer and others 
 
 prefume, that there is no Sand in nature 
 entirely free from Gold. See Gold. 
 
 (e) Deliquiation of Flint and Alcali.) The 
 proportion of Alcaline Salt for obtaining with 
 Flint either a deliquiable or a truly vitreous 
 compound, depends greatly on the degree 
 and continuance of the fire. A mixture 
 of powdered Flint with an equal quantity of 
 the Salt, if taken out of the furnace as foon 
 as it appears melted, will liquefy by degrees 
 upon expofure to the air: but if the fire is 
 kept up ftrong for feveral hours, though the 
 quantity of Salt be more than doubled, the 
 refult will be a perfect and durable glafs ; 
 all the fuperfluous Alcali being diffipated 
 by the vehemence of the heat. One part 
 of Alcali and two of Flint have been faid to 
 deliquiate : But this mixture requires a very 
 ftrong fire for its fufion ; and when per- 
 fectly melted, proves a femitranfparent glafs, 
 of confiderable hardnefs, fo as freely to 
 ftrike fire with Steel. Glafs in general is 
 found to be harder in proportion as it con- 
 tains lefs Salt. 
 
Earths and Stones. 
 
 Jates alfo with metallic folutions made in Acids; that of Corrofive Sublimate, Flint, 
 or of Mercury in the Marine Acid excepted ; this folution yielding with the 
 Liquor Silicum , as with pure Alcalies, an orange yellow Precipitate, and fcarce 
 diicovering any tendency to become curdly. It likewife becomes confiderabiy 
 thick or confident, with fome folutions of Earths in Acids, as that of Quick- 
 lime in the marine. If loaded with the Flint, as the liquor prepared from 
 equal parts of Flint and Alcali, it grows thick, upon Handing for fome time, 
 without any addition. The coagulum which it forms with folution of Mer- 
 cury in the nitrous Acid appears variegated, reddilh, yellowifh, and grey: 
 the others are more uniform (/). 
 
 There have been many pretences of extraditing from Flint, Salts, Spirits, 
 
 Tindlures, &c. and many preparations of it recommended by the Chemifts, 
 both for medicinal and the fublimer metallurgic ufes ; from a groundlefs 
 conceit, that this Stone was poffefled of lithontriptic powers, and impregnated 
 with a folar Sulphur. It has been faid that Flints, by repeated ignition and 
 extin&ion in water, change at length into a flimy fubdance, from which may 
 be procured, by didillation, a Spirit and an Oil : Becher, Stahl, Henckel and 
 others mention this procefs, and promife notable effects from it on metallic 
 bodies: But upon trial, an hundred repetitions of the extinction made no other 
 change in the Flint than rendering it friable; nor did the water, in which the 
 ignited Stone had been fo often quenched, appear to have received from it 
 any impregnation, which fome pretend it does, or to differ fenfibly from the 
 pure water employed. Glauber and others recommend diftilling the Flint with 
 equal its weight or more of fixt Alcaline Salt: this mixture, if the fire is 
 raifed high enough to melt it, emits vapours refembling thole of the acid of 
 Sea-Salt: The mafs, deliquiated in the air, emits vapours of the fame kind 
 on the affufion of Oil of Vitriol : It does not however follow that the marine 
 Acid, extricated in thefe experiments, exifted in the Flint ; the Alcali, with- 
 out the Stone, yielding the fame marine vapours. 
 
 If any Acid exifts in Flints, it fhould feem to be the Vitriolic ; and that they Contains v , t 
 contain a portion of this, there is lome foundation to prefume. If Flints be Holic Acid, 
 mixed with Nitre, and expofed to a moderate fire, the Acid of the Nitre will 
 be remarkably extricated ; the known effect of the Vitriolic Acid alone. In a 
 ftrong fire indeed, the Flint as an Earth would expel the nitrous Spirit ; by 
 abforbing and vitrifying with its alcaline bafis : but here the extrication hap- 
 pens long before the heat has been raifed high enough for vitrification (£). 
 
 (y*) Liquamen of Flints.] The Flint is 
 precipitated from this folution of it in fixed 
 Alcalies, not only by Acids, but likewife, 
 as the German editor obferves, by Volatile 
 Alcalies. The Earth thus recovered either 
 by one or the other is found to be remark- 
 ably altered ; to be now diflbluble in Acids 
 which it entirely refilled before. Sand and 
 Cryftal fuffer the fame change— -Whether 
 this effect is owing to a change made in the 
 earth itfelf, or the feparation of any particu- 
 lar matter from it, has not hitherto been ex~ 
 
 II. CRY. 
 
 amined though highly deferving of enquiry, 
 (g) Probably Vitriolic Acid, in Flint.] In the 
 making of common Glafs with Flint, when 
 the quantity of matter is large, a faline 
 fubftance arifes to the fur face during the fu- 
 fion, commonly called Sandiver or Glafs- 
 gal! : this, though no Vitriolic Salt was 
 employed in the compofition, is found to 
 participate largely of that Acid, and to be 
 nearly fimilar to Sal Mirabile. Did the 
 Vitriolic Acid pre-exift in the Flint, or was 
 it generated during the procefs ? 
 
 
6 
 
 Earths and Stones. 
 
 II. CRYSTAL. 
 
 Crystal. RY S TA L is one of the hardeft Stones next to the Gems {h ) : by fome It 
 , . has been ranked in that clafs. It is iometimes colourlefs and pellucid as 
 
 Natural hif- Glafs ; though often tinged of a yellowifh, brownilh, or other colours. It is 
 toiy. generally of a regular figure, namely that ol' an hexagonal column with un- 
 
 equal Tides, terminated by an hexagonal pyramid: in rivers, it is fometimes 
 found with the angles rounded off, and fometimes quite round. The maffes 
 are commonly fmall, though fometimes of confiderable magnitude : In the 
 Breflau Collections for the year 1725, there is an account of a piece of Cryftal 
 found near Zittau, and thence brought to Drefden, which weighed upwards of 
 four hundred weight: In the Imperial Collection at Vienna, there is a pyrami- 
 dal 
 
 ( b ) Gems.] The Gems or precious Stones 
 are the hardeft of all natural bodies. Art 
 has imitated moft of them in other refpedts ; 
 but no artificial compofition comes near 
 them in point of hardnefs. They have 
 been fuppofed to be entirely unfubduable by 
 common fire ; but experiment fhews, that 
 they calcine and become pulverabie like the 
 other Stones of this clafs, though more dif- 
 ficultly in proportion to their greater hard- 
 nefs. The Diamond itfelf, as Pott ob- 
 serves, in a vehement fire, lofes all its luftre 
 and tranfparency, becomes milky, friable, 
 and fplits into fine leaves like Talc. The 
 Hyacinth and Garnet come at length into 
 acftual fufion j changing their red colour to 
 a dark black, but preferving even in this 
 form a great degree of hardnefs : Both the 
 colour and the fufibility of thefe Stones ap- 
 pears to proceed from Iron, a portion of 
 which is feparable from them by the Mag- 
 net. The blue tinclure of the Sapphire, 
 the purple of theAmethyft, and the green 
 of the Emerald, are more perifhable ; being 
 totally deftroyed by a moderate degree of 
 heat, fo as to leave the Stones colourlefs as 
 Cryftal. The Emerald, in lofing its co- 
 lour in the fire, tinges the flame bluifh. 
 
 Mr. Pott, in the Berlin Memoirs, has 
 given a curious fett of experiments on the 
 Saxon Topaz, which is reckoned the hard- 
 eft of all the Stones, except the Diamond, 
 Sapphire and Ruby. This Stone, reduced 
 to powder after repeated ignitions and ex- 
 tindlions, refufed to melt with even ten 
 times its weight of fixt Alcaline Salt ; great 
 part of the Alcali tranfuding through the 
 crucible, inftead of adfing upon the Topaz. 
 A portion of Sea-Salt was added to the Al- 
 
 cali without any better fuccefs ; but on add- 
 ing Borax, the cafe was altered : two parts 
 of Topaz, with no more than one of Alcali 
 and one of Borax, melted into a tranfparent 
 glafs, in colour inclining to yellow. On 
 takino- Nitre inftead of Alcaline Salts, the 
 event was the lame : in whatever propor- 
 
 tion Topaz and Nitre were mixed, they re- 
 filled vitrification ; but by the mediation of 
 a proper quantity of Borax, they melted, 
 perfectly together. Borax alone alfo was 
 found to bring the Topaz into fufion, and 
 this even when the quantity of the Borax, 
 was no greater than one half of that of the 
 Stone. The powdered Topaz, mixed with 
 thrice its weight of Chalk, vitrified, in a 
 vehement fire, without any faline addition, 
 at all. It melted likewife, not only with, 
 the fufible Calces of Lead, but with the un- 
 fufible ones of Copper. 
 
 The Topaz appears from thefe experi- 
 ments not to confift wholly of Cryftalline 
 Earth ; fince the pure Cryftalline Earth vitri- 
 fies more eafily with Alcaline Salts than with 
 Borax, and does not vitrify at all with 
 Chalk. Any of the other fimple Earths, 
 mixed with the Cryftalline, renders it more 
 eafily fufible with Borax than wfith Alcali ; 
 but the only one that renders it fufible with 
 Chalk is the Argillaceous : hence it is not 
 unreasonable to fulpecf, that the precious 
 Stones are compofed of the Cryftalline 
 Earth mixed with the Argillaceous. If 
 this Should be the cafe, the proportion of 
 Argillaceous Earth cannot be large ; for if 
 it was, the Stone, inftead of growing fri- 
 able, would gain additional hardnefs in the 
 fire. 
 
Earths and Stones. j 
 
 dal Cryftal Vafe two ells in height, cut wholly out of one piece— — Pieces Crystal, 
 are fometimes met with, which have different foreign bodies included within 
 them: I have feen leaves and ftalks of Plants, Hay, Straw, Hogs Bridles, in- 
 doled in fprigs of Cryftal. 
 
 Cryftal is lomewhat more difficultly fufible than Sand, and is faid to afford a vitrificatiosi. 
 fomewhat harder Glafs : it requirea by itfelf about an equal weight ofAlcali 
 for its vitrification ; of Borax, if mixed with a little Lapis Specularis, a 
 fmaller proportion proves fufficient. With half its weight of Alcali, itformed a 
 violet blue mafs : by varying the proportions, I have obtained brighter and 
 
 darker blues, and brownifh red compounds (z). Like the other bodies of this 
 clafs, it refilled the folar heat, and faline Menftruums ; and gave no impreg- 
 nation to Water on being repeatedly quenched in it. Becher pretends to re- 
 duce it into the confiftence of a Jelly, that fhall flow in a moderate heat like 
 Wax. 
 
 Cryftal may be tinged of a variety of colours, by expofing it in a clofe cru- Methods of 
 cible to the vapours of Orpiment, or of Antimony and Arfenic (k ) ; or by colouring, 
 quenching the ignited Stone in coloured liquors : Tindlure of Cochineal gives 
 a bright red ; Tindture of red Saunders, a dark red ; Tindture of Saffron, 
 according as it is more or Id's faturated, a dark and a bright yellow ; Solu- 
 tion of Lacmus, a bright blue; Juice of Buckthorn Berries, a violet blue ; a 
 mixture of Solution of Lacmus and Tindture of Saffron, a green. 
 
 CLASS 
 
 (i) Blue and reddijh maffes from Cryfal . ] 
 Probably the Cryftal, employed in thefe ex- 
 periments participated of cupreous or other 
 heterogenous tinging matters, for pure Cry- 
 ftal gives a colourlefs Glafs. That this 
 Glafs is either harder or more tranfparent 
 than fuch as is made from Flint, as it is 
 commonly fuppofed to be, did not appear 
 upon companion. 
 
 (k) Colouring of Cryfal.] This method of 
 colouring Cryftal was firft defcribed by Neri 
 in his art of Glafs *. He diredfs Antimony 
 and yellow Orpiment of each two ounces, 
 and one ounce of Sal Ammoniac, to be 
 mixed together and put into a crucible ; 
 and fome pieces of clear Cryftal to be laid 
 above the mixture, the fmaller ones at 
 the bottom and the larger at top, till the 
 vefiel is full : another crucible, having a 
 fmall . hole in its bottom, is to be inverted 
 into the former by way of cover, and the 
 juncture clofely luted : the whole is then to 
 be placed in a convenient furnace, and fur- 
 rounded with charcoal to about half the 
 height of the upper crucible : the fire is to 
 be raifed by degrees, kept up, gentle, till 
 
 the fumes difappear, and then fuffered to go 
 out of itfelf ; care being taken to avoid the 
 poifonous vapours : the uppermoft pieces of 
 Cryftal are found tinged with Gold, Ruby, 
 Opal, and other beautiful variegations ; and 
 moft of the lower ones of a viper colour. 
 He gives another procefs, in which the in- 
 gredients are, yellow Orpiment and white 
 Arfenic of each two ounces, and Crude An- 
 timony and Sal Amoniac of each one ounce. 
 The Cryftal, in thefe operations re- 
 ceives very elegant colours, but is apt to 
 become full of cracks, and hence unfit for 
 being cut or polilhed. Kunckel fuppofes 
 the colour to be wholly owing to the Fif- 
 fures of the Stone retaining the colouring 
 particles : but though this is often, it is not 
 always the cafe, fome pieces being tinged 
 throughout, without any vifible fiflure : his 
 own words infinuate, that fome receive the 
 full tindfure, without thofe imperfedtions. 
 I have known bodies of the Cryftal kind, or 
 at leaft equal to Cryftal in compadtnefs and 
 tranfparencv, penetrated above an inch by 
 certain vapours," though not the leaft fiflure 
 or imperfection could be difcerned. 
 
 * Book iv. Chap. 73. 
 
8 
 
 Earths and Stones. 
 
 Chalk. 
 — ■■ /• 
 
 Natural Hif 
 tor y , 
 
 With Acids. 
 
 CLASS II. Calcareous Earths and Stones. 
 
 Earths and foft Stones,— reducible by fire into ^uick-lime } — readily foluble 
 in the nitrous , marine , and vegetable Acids, both in their natural fate 
 and when calcined. 
 
 I. CHALK. 
 
 C HALK is a white Earth, found plentifully in England, France, Nor- 
 way, and other parts of Europe; laid to have been anciently dug chiefly 
 in the ifland Crete or Candy, and to have thence received the name Greta. 
 Some attribute the excellency ol the grapes and the wines of Champagne to the 
 chalky foil abforbing acid juices ; a theory which would be abundantly plau- 
 fible, if the unripe grapes had no acidity. 
 
 The bell; Chalk is of perfect whitenefs, foft yet clofe and folid, equal and 
 uniform when broke, free from Sand or fmall Stones. Powdered, and walhed 
 over from any gritty matter that may be naturally intermixed, it is called 
 Whiting; and in this (late is bed; adapted for medicinal and chemical ufes, 
 as well as the oaconomical ones of cleaning and polilhing metalline or glafs 
 utenflls, &c. Chalk readiiy imbibes water; and hence maflfes of it are em- 
 ployed for drying Precipitates, Lakes, earthy powders that have been levi- 
 gated with water, and other moift preparations. 
 
 Oil of Vitriol poured upon Chalk raifes a ftrong effervefcence with a bitu- 
 minous vapour, but fcarcely difloives any of the Earth : if more and more of 
 the Acid be gradually added, the whole continues quiet, without any further 
 confiderable effervefcence or folution. If the Acid be diluted with water, it 
 difloives fome portion of the Chalk (l). All the other Acids readily and to- 
 tally diflolve it : four ounces of Spirit of Nitre took up one ounce ; the fame 
 quantity of Spirit of Salt, fix drams; and the fame quantity of diftilled Vine- 
 gar, three drams. The adtion of the nitrous Acid was accompanied with a 
 confiderable frothing, but no heat or red fumes. 
 
 Solutions of Chalk in the nitrous and marine Acids, are extremely bitter; 
 thofe made in diftilled Vinegar are much lefs lo. None of them perfectly 
 cryftallize ; nor, if infpiflated, do they long retain a dry form : how carefully 
 foever they be exficcated by fire, they deliquiate again in the air, though one 
 
 more 
 
 (/) Chalk with the Vitriolic Acid . ] Chalk 
 does not thlfolve, or but in fmall quantity, 
 in the Vitriolic acid whether concentrated 
 or diluted. This Acid has neverthelefs a 
 very ftrong affinity with Chalk ; abforbing 
 it from all the other Acids, and forfaking 
 even Alcaline Salts to unite with it. If 
 this Earth be diflolved in Spirit of Nitre, 
 Spirit of Salt, or diftilled Vinegar ; the ad- 
 dition either of the pure Vitriolic Acid, or 
 of compound Salts containing it, renders 
 the liquor inlfantly milky or curdlyj the 
 
 Chalk being now combined with that Acid 
 into a concrete not at all, or exceeding 
 lparingly, diffoluble. If the Solution of' 
 Chalk be largely diluted with water before 
 the addition of the Vitriolic Spirit, the li- 
 quor continues for a time tranfparent: oh 
 itanding it becomes wheyilh, and at length 
 depofites cryftalliform concretions, which 
 are found to be true Selenitae or gypfeous 
 Mafles; being indiftoluble in Acids, cal- 
 cining in veflels into Plafter, and in contadf 
 with the fuel into Quick-lime. 
 
Earths and Stones. 9 
 
 more readily than another. It has been faid, that Chalk forms with the Vi* C h a l k. 
 triolic Acid a perfect Alum : It may indeed be combined with that Acid into a u— v — 
 cryftalline form, but theCryftals prove extremely different, in tafte as well as 
 in their other qualities, from thofe of Alum : the Aluminous Earth is a fub- 
 flanceof a peculiar kind, hitherto nowhere difcovered but in the Alum itfelf, 
 
 (See Alum) Solution of Chalk in the nitrous Acid forms, on evaporation, a te- 
 nacious mafs like Turpentine ; which exficcated, and calcined a little, proves 
 luminous in the dark. This Phofphorus is ufually diftinguifhed by the name 
 of its tirtf difcoverer, Balduin : it is called alfo Phofphorus Hermeticus , from its 
 being kept in hermetically fealed glaffes to fecure it from the air. It differs 
 from fome other Phofphori, in appearing in fome degree luminous, after expo- 
 fure to the light of a taper as well as of the fun. 
 
 Chalk is precipitated, from its folutions in both the mineral Acids, by vo- 
 latile and by fixt Alcalies, into a white Powder; provided the Solutions are 
 confiderably diluted with Water. When the undiluted Solutions are mixed Coagulation, 
 with faturated Alcaline Liquors* inftead of a precipitation, the mixtures coa- 
 gulate, and become fo thick, that the glafs may be turned upfide down with- 
 out fhedding its contents. 
 
 Pure Chalk melts eafily with Alcali and Flint into a tranfparent colourlefs Vitrification 
 Glafs (m). Calcined, by a ftrong fire into Quick-lime, it lcfes much of Its of CiiaIk * 
 difpofition to vitrify : It is now found to melt very difficultly and imperfectly, 
 
 and 
 
 ( m ) Vitrification of Chalk.'] Chalk vitrifies 
 with Alcaline Salt fomewhat more difficult- 
 ly, and with Borax fomewhat more eafily, 
 than Flint or Sand : it requires about equal 
 its own weight of the Alcali; of Borax, 
 half its weight is fufficient : the glaffes made 
 with both, particularly thofe with Borax, 
 are commonly of a fine pale green or yellow 
 colour. Sal Mirabile and Sandiver, which 
 do not vitrify at all with the cryftalline 
 Earths, form, with half their weight of 
 Chalk, the firft a yellowiffi black, the lat- 
 ter a greenifh Glafe. Nitre, on the other 
 hand, one of the rnoft adlive fluxes for 
 Flint, does not perfectly vitrify with 
 Chalk. 
 
 Vitrification of Calcareous with other Earths. ] 
 Chalk notably promotes the vitrification of 
 Flint; a mixture of the two requiring lefs 
 Alcali than either of them feparately. If 
 Glafs made from Flint and Alcali he fatu- 
 rated' with the Flint, fo as to be incapable 
 of bearing any further addition of that 
 Earth, without becoming opake and milky ; 
 it will ftil-1, in a ftrong fire; take up a confi- 
 derable proportion, one fourth or one third 
 its weight, of Chalk, without injury to its 
 tranfparency. Hence Chalk is fometimes 
 employed in compofitions for Glafs, as a 
 
 part of the Salt may then be fpared. 
 
 Mixtures of Chalk with pure white Clay 
 melt without any addition : they are diffi- 
 cultly brought to perfedt tranfparency in 
 veffels ; but if expofed to the immediate 
 action of the fire, in contact, with the burn- 
 ing fuel, they vitrify with eafe. I have 
 made covers for crucibles of fuch a compofi- 
 tion, and unexpectedly found them melt, in 
 no very vehement heat, into a hard, tran- 
 fparent, yellow Glafs ; they often melted 
 anddropt down into the crucible before the 
 vitreous compofitions included in it had be- 
 gun to run. The addition of Flint or Sand 
 promotes the vitrification. 
 
 Mr. Pott has given fome interefting expe- 
 riments of the effedts of Chalk on the ftony 
 matters intermixed among or invefting me- 
 tallick Ores. Some of thefe Stones are fo 
 hard as to ftrike fire with Steel, and either 
 pellucid and colourlefs, or lefs tranfparent 
 and fomewhat milky. Others are fo foft as 
 to be cut with a knife, remarkably heavy, 
 when pure of a milky whitenefs inclining 
 a little to yellow, generally of a leafy or 
 Urivery texture, fometimes tinged with red, 
 green, and other colours refembling thofe 
 of the Gems, whence the names Pfeudo- 
 hyacinthus , Pfcudo-fnarogdus , &c. Of thefe 
 C fofter 
 
io Earths and Stone s. 
 
 C h a l k. and render the Glafs milky. In cither ftate, it does not vitrify of itfelf in the 
 moft intenfe fires; and is fuppofed in fome mealureto refill the adtion of Glafs 
 olLead, Luna Cornea, and fome other fubftances, which foon corrode and 
 penetrate the common earthen veftels : hence fome have been accuPcomed, for 
 detaining thole bodies in fufion, to line the crucible with Chalk made into 
 a pafte with Solution of Borax. 
 
 Chalk added to Antimony in fufion is Paid to abforh the fulphureous part of 
 that Mineral, and precipitate the Reguline or Metallic to the bottom. On 
 trial this experiment did not fucceed : two ounces of powdered Chalk being 
 ftirred, with a clean tobacco-pipe, into four ounces of melted Antimony ; and 
 three ounces of Chalk mixed in the fame manner with five ounces of Anti- 
 mony; there was no feparation, in either cafe, of any ReguJus ; the whole 
 remaining equally mixed. That the Chalk had neverthelefs adled upon the 
 Sulphur, appeared upon boiling a little of the mafs in water: the liquor be- 
 
 came tinged, as from Sulphur combined with Alcalies, and on the addition 
 of Vinegar, depofited a Precipitate refembling the golden Sulphur of Anti- 
 mony. 
 
 Henckel, in his Pyritologia, relates a remarkable experiment of a granule 
 of Silver being obtained by barely mailing the common fulphureous Pyritae 
 with Chalk; though neither one or the other, examined feparately with diffe- 
 Chalk treated rent additions, difeover any footftep of that metal. I have treated Chalk 
 with inflam- w j t h various inflammable fubftances, without being able to obferve the leaft 
 flancel U ' mar ^ °f an y thing metallic. With Ample inflammable matters, as Tallow, 
 Pitch, Wax, powdered Charcoal ; the Chalk remained a white, remarkably 
 fpongy, light, crumbly mafs, notably dimimflied in weight: from two ounces 
 of Chalk and one ounce of Charcoal, no more than an ounce was left ; all the 
 reft being volatilized (»). With fixt Alcalies on the other hand, it melted 
 into a compadl vitreous mafs, whofe deficiency in weight was only half an 
 ounce upon two ounces of Chalk and one ounce of the Alcali. 
 
 . " It 
 
 Chalk with 
 Antimony. 
 
 Silver pro- 
 duced. 
 
 fofter Stones^ there are two different kinds, 
 fcarce to be diftinguilhed by the eye, but 
 eafily by a little Aqua fortis, which effer- 
 vefees with and diffolves one fort, but has 
 
 no adtion on the other. ^The ioluble loft 
 
 Stones, and the pellucid hard ones, are 
 little affedted by Chalk: the indiffoluble 
 foft, and the milky hard ones, though en- 
 tirely unfufible of themfelves, melted rea- 
 dily with this Earth, flowed thin as water, 
 and when the fire was kept up for fome 
 time, run clean through the crucible. 
 Whether the Chalk or the Stone prevailed 
 in the compofitions, whether four parts of 
 the Chalk were taken to one of the Stone, 
 or four parts of the Stone to one of Chalk, 
 the fame furprizing fufibility was always 
 obferved. Thefe mixtures brought Earths 
 of all the other claffes alfo into fufion along 
 
 . 1 - ■ ‘ i • 
 
 with them ; and when faturated with thefe, 
 were lefs apt to corrode the veffel. Diffe- 
 rent calcareous bodies, as Chalk, Lime- 
 ftone. Marble, had the fame eftedts : but 
 the mineral Stones differed a little in point 
 of fufibility, the foft being more fufible than 
 the hard — Thefe experiments may probably 
 be applicable to valuable purpofes in the 
 running down of Ores. 
 
 («) Chalk volatilized,.] All the calcareous 
 Earths and Stones lofe a large proportion 
 of their weight on being urged with a ftrong 
 fire without any addition : The harder 
 the Stone, the lefs is the dillipation. Chalk 
 lofes near two-thirds of its weight in being 
 burnt into Quick-lime ; the harder cal- 
 careous Stones, as Marble, about half their 
 weight. 
 
Earths and Stones. ii 
 
 It has been faid, that Sope diftilled with Chalk turns ali to water : but on Chalk. 
 trial, this did not fucceed. Chalk, which as we have already feen unites — v - — > 
 eafily with Alcalies in the fire, abforbs the Alcaline Salt of the Sope; upoii Vv ^ So P e - 
 which the water of the Sope diftils, along with its Oil, now rendered empyreu- 
 matic by the heat. If the diftilled liquor be repeatedly drawn over from lie fn 
 parcels of Chalk, lefs and lefs Oil will be obtained in every diftillation, till 
 all the Oil is, as all Oils are by the fame treatment, deftroyed. 
 
 Chalk mixed with Sal Ammoniac, extricates no urinous fmell : but if the With Sal Am- 
 
 mixture beexpofed to the fire, the Chalk will then ad upon the Salt, abforb moniac. 
 its Acid, and difengage its Volatile Alcali, which is thus obtained in its pro- 
 per concrete form. See Sal Ammoniac. 
 
 Chalk is employed, in medicine, againft the heart-burn, and other com- Medicinal 
 plaints arifing from acidities in the firft paffages ; and fometimes as a deficca- u(es * 
 tive for running fores and ulcers. It is the bafis of the cardialgic troches of 
 the fhops ; to which fome prefer Chalk itfelf in powder; the Sugar, which 
 enters in large quantity in the troches, being often found to aggravate 
 thofe complaints. Chalk is more ftyptic than mod of the other abforbent 
 Earths, and therefore to be ufed with caution. Some have taken it freely, 
 for procuring a white complexion ; but its more certain effects are gripes and 
 obffrudions. It is fometimes employed for curing Wines or Malt Liquors 
 on the fret : it takes off' their acidity, but renders them very apt to grow vapid. 
 
 In the Chalk-pits are found black or blackifh brown femitranfparent Stones, Stones m 
 fo hard as to ftrike fire with Steel Many of thefe appear externally whitiffi Cha ^'P lt& * 
 and corroded as it were; and on being broke, prove gradually more compact, 
 and darker coloured, from the furfaee to the center; as if the Chalk was pro- 
 duced from a corrofion and refblution of the Stone by mineral vapours. On 
 this prefumption, fundi y trials were made for obtaining a like refolution by 
 art. The Stones were calcined by the greateft heat procurable in a potter’s 
 furnace ; but they remained as compact and folid as at firft, and what is re- 
 markable, loft nothing of their weight. Calcination in mixture with Pit-coal 
 fucceeded no better : nor did expoiure to the fumes of Pit-coal, or of Sulphur, 
 make any change in the Stone. The pulverifed Stone, mixed with Sulphur, 
 and calcined, fullered no diminution, nor any other alteration than becoming 
 darker coloured. The Powder, both calcined and uncalcined, was examined 
 alfo with Acids ; but none of them had any addon on it, except that Oil of 
 Vitriol acquired from the crude Stone a red tinge; which that Acid readily 
 does from any thing impregnated, however (lightly, with inflammable matter. 
 
 Thefe Stones appear therefore to be of a different nature from Chalk, and to 
 belong to another clafs [the Cryftalline]. ; 
 
 II. O S T E O C O L L A. 
 
 QSTEOCOLL A is a foflil fubftance, found in fandy grounds, in feveral Osteocol. 
 
 parts of Germany ; fpreading from near the furfaee, to the depth of 
 fix, ten and more feet, like the roots of a tree; fome of the ramifications are^ J ' 
 
 others, no thicker than a quill. Whilft under the 
 C 2 earthy' 
 
 as large as a child’s arm 
 
i2 Earths and Stones. 
 
 Osteocol. earth, it is foft, almoft like flaked Lime tempered with Sand, To as fcarce to 
 be got up entire: in colour it is fometimes yellowifh or brownifih, but moft 
 commonly greyifh or whitifh. Dried, it becomes whiter and harder, and 
 fometimes exhibits reddifhor yellowifh fpecks or veins. Mod of the pieces are 
 internally hollow : fome have a core of a corrupted woody matter. 
 
 Hiftory. The origin of this concrete has been greatly controverted, and greatly mif- 
 
 underftood. Moft of the ancients imagined it to be petrified Bones, though it 
 has no relemblance in figure to any kind of Bone: fome have fuppofed it a 
 
 truly mineral fubftance, proceeding from the finer parts of the Sand, among 
 which it is always found, conglutinated together by fubterraneous vapours-, 
 whence it has been named Lapis Sabulofus. Ferrantus Imperatus, in his IJloria 
 Naturale firft publifhed in 1599, gives a copper-plate °f three pieces of Ofteo- 
 A petrified colla, under this title : “ Ofteocolla is a petrified root, compofed of a foft 
 
 root, “ cement and a fandy fubftance, employed by the German phyficians for 
 
 “ confolidating broken bones.” That this is its true original, I have been 
 convinced from ocular obfervation : After many fruitlefs fearches, I found 
 at laft, near the village of Tfchernow or Tfcharno, the remains of the trunck 
 of a tree with a living branch upon it, and its roots changed wholly into 
 Ofteocolla. The tree was the common black poplar, Populus nigra, C. B. ( 0 ). 
 
 examined by Diluted Spirit of Vitriol poured upon Ofteocolla, totally dififolved it, with 
 Acids, 1 st. C onfiderable effervefcence : fome cryftalline concretions feparated from the 
 liquor, but on adding mere of the Acid they were taken up again : the Solu- 
 tion being infpifiated, the dry mafs was found to weigh one fixth more than 
 the Ofteocolla at firft. The concentrated vitriolic Acid, on the other hand, 
 
 diflolved 
 
 (0) Natural Hijlory of Ofeocolla.) The 
 author’s account of this curious foffil is con- 
 firmed by the obfervations of Mr. Gleditfch, 
 who in the Berlin memoirs for the year 
 1748, has given a particular defeription of 
 it as met with in the marquifate of Bran- 
 denburg. It is dug among Sands, which 
 are faid to have been once covered with 
 forefts, where fome Pines and Birches ftill 
 remain, and where he found a living Pine 
 with part of its root changed into Ofteo- 
 colla. The Ofteocolla is externally full of 
 knobs, and often has a cavity running 
 along one fide : no mark is left of the Bark 
 or woody circles, but fometimes, though 
 rarely, the Parenchyma is found at the ex- 
 tremity of the root : no fmall fibres are feen, 
 but there are protuberances and cavities, 
 which plainly diftinguifh the places where 
 they iffued from : fome pieces, efpecially the 
 larger ones, are enclofed in a particular kind 
 of fubftance, not very compact, confifting 
 manifeftly of the mouldered Bark and rotten 
 woody parts. Some large branches difeover, 
 on breaking, the remains of the petrified 
 
 wood ; others have a hard woody core al- 
 moft like Horn, extending fometimes to the 
 length of five or fix feet. The fubftance 
 of the Ofteocolla is internally foft and of 
 a loofe texture ; externally harder and 
 fandy, fometimes, efpecially in the fmall 
 branches, fo hard as to ftrike fire with 
 Steel. 
 
 The Sands in which the Ofteocolla is 
 met with, have an admixture of a fine white 
 calcareous Earth, which flicks to the fin- 
 gers, looks like meal, and when wafhed 
 down from the higher grounds by rains and 
 colledled in cavities, appears in form of an 
 emulfion. The Sand adjoining to the Ofte- 
 ocolla abounds moft with this Earth ; and 
 the foffil itfelf appears to be compofed of 
 the fame Earth mixed with the Sand. If 
 powdered Ofteocolla be agitated with wa- 
 ter, the calcareous Earth remains for a time 
 fufpended, fo as to be poured off with the 
 liquor, whilft the Sand is left behind. The 
 Sand and Earth are nearly in equal propor- 
 tions. 
 
Earths and Stones. 13 
 
 diffolved only eight grains out of fixty; though more and more of the Acid Osteocoe. 
 
 was added to the Powder, fo long as it occafioned any effervefcence : the co- ' — ■— * * 
 
 lour of the Solution was a Gold yellow. Spirit of Nitre, Spirit of Sea-Salt, 
 and Aqua Regis, diffolved each twenry-four or twenty-five grains out of fixty; 
 nor would a frefti addition of either of thefe Acids take up any more : Aqua 
 
 Regis feemed to ad: the moft difficultly of the three, and when added in an 
 over-proportion, after the Solution had been faturated, precipitated a part of 
 what had been before diffolved. Diftilled Vinegar took up but ten grains, or 
 one fixth of the Ofteocolla. 
 
 Diftilled Water, long boiled with an ounce of Ofteocolla, appeared, after 
 repeated filtrations, turbid and milky. On (landing for a length of time, it 
 depofited a fcruple of an extremely fine Powder, and became clear : the liquor, 
 being now examined by Alcalies, Acids, and Syrup of Violets, gave no 
 marks of its having received any Saline impregnation from the Ofteocolla. 
 
 Alcaline Lixivia boiled with this Concrete, appeared upon moft trials to be 
 ftill merely Alcaline ; but on adding to the infpiffated liquor fome Oil of 
 Vitriol, vapours arofe like thofe of Spirit of Sea- Salt, and on (landing for a 
 length of time, a little flippery curdly matter feparated. 
 
 Forty-eight ounces of frefh Ofteocolla, diftilled in a glafs retort, gave firftBy diilillatl- 
 eight ounces of an almoft infipid and inodorous phlegm ; then three ounces of on ” 
 a bituminous liquor, and at laft one ounce of a ftronger fpirit, which fmelt 
 confiderably of Petroleum, eftervefced with Oil of Vitriol, and changed Syrup 
 of Violets green. Frefti foft Ofteocolla, diftilled with Oil of Vitriol, in a tu- 
 bulated retort, yielded an Acid Spirit, the fame with that of Sea-Salt: by 
 faturating the Spirit with Salt of Tartar, I obtained a true regenerated Sea- 
 Salt; and by diftilling this Salt again with Oil of Vitriol, a concentrated Spi- 
 rit of Salt. Frefti Ofteocolla, which had been boiled in Water, ftill yielded 
 with the Vitriolic Acid a Marine Spirit. 
 
 Ofteocolla calcined in an open fire, loft in weight four fcruples upon halfBy calcinati- 
 an ounce, and became fomewhat duller in colour: Water boiled on the calx, on and vitrifi “ 
 made no effervefcence on the admixture of Alcalies, and depofited no Precipi- Catl0n * 
 tate; but Oil of Vitriol mixed with it extricated vapours of Marine Acid. 
 
 Equal parts of powdered Ofteocolla and fixt Alcaline Salt, urged in a crucible 
 with a ftrong fire, melted into an untranfparent vitreous matter, moderately 
 hard, and of a grey colour : Water extracted from this mafs a part of the 
 Alcali, as appeared from the liquor changing Syrup of Violets green (p). 
 
 LIME- 
 
 (p) Chemical hijlory of Ofteocolla . ] Mr. 
 Margraff, in the memoirs above-mention- 
 ed, has given a more particular examina- 
 tion of this Concrete. Eight ounces of one 
 of the pureft pieces (taken from a Pine- 
 tree) were feparated, by wafting over with 
 water, into four ounces and a half of white 
 
 Earth, and three and a half of Sand 
 
 The Earth effervefced with Acids, and 
 formed with them the fame compounds as 
 Chalk or Limeftone: Uniting with the Vi- 
 
 triolic into a thick fubftance like pap, which 
 diluted with water yielded on evaporation 
 a few fmall oblong Cryftals : almoft totally 
 diftblving in the nitrous and marine, refuf- 
 ing to cryftallize with either, when exfic- 
 cated by fire deliquiating again in the air; 
 yielding with the nitrous a Phofphorus, the 
 fame with that of Balduin formerly menti- 
 oned. Calcined, it became a true Quick- 
 lime, not differing on any trial from the 
 
 common Limes —The Sand of Ofteo- 
 
 1 colla, 
 
34 
 
 Earths and Stones. 
 
 III. LIME-STONE. 
 
 L. Stone. T I ME- STONE is a general name for all the Stones from which Quick-lime 
 
 » - v — — > is commonly prepared. Of thefe there are a great variety : fome are pale 
 
 Natural Wif- co ] 0 u re d, grey, whitifh, or yellowifh ; others darker, brownifh or reddifti : 
 fome are of a fpongy, fcaly, or fhivery texture ; others, clofe and compaft : 
 fome entirely opake, others femitranfparent. They are of all degrees of hard- 
 nefs, from Chalk up to Marble; which 1 aft is the hardeft of the Stones that 
 are convertible into Lime. The fofter kinds are generally made choice of 
 for burning: and the harder employed as building-ftones or for other ufes : 
 
 the Lime ul'ed about London is made chiefly from Chalk, Sea-fhells likewife 
 afford a good Lime, and in fome maritime places fupply the want of the pro- 
 per mineral Stones. 
 
 Contains All Lime-ftones contain a portion of ftilphureous matter, as is evident from 
 Acid, ifc. ^ ft ron g fmeil which arifes in burning them, and which extends to a confi- 
 derable diftance from the kilns. The Lime-ftones ufed in this country yielded 
 in diftillation an Acid Liquor, which turned Syrup of Violets red, precipitated 
 Solution of Silver, and formed with Mercury a corrofive Sublimate ; a proof 
 that the Acid was marine. The fame Acid was diftovered alfo after the Stone 
 had been burnt into perfect Lime; Oil of Vitriol extricating from the Calx 
 vapours manifeftly marine. The Limes prepared from different Stones, 
 though they may anfwer equally for morter and other common ufes, are found 
 to differ confiderably in fome of the nicer chemical experiments. 
 
 IV. QJJ I C K-L I M E. 
 
 Qu Li m e. QU ICK- LI ME is an acrid Calx, fo corrofive as to be employed by the 
 ■ — * tanners for deftroying the fat and flefhy parts of fkins, and occafioning 
 
 General pro- the hair to feparate. It raifes a ftrong heat and ebullition on the affufion of 
 perties. water, and in part diffolves ; rectified Spirit of Wine has fcarcely any atftion 
 on it, and oils none at all. Slaked with water, or moiftened into the con- 
 fluence of a pafte, and mixed with a proper quantity of Sand or other hard 
 bodies, it acquires a notable degree of hardnefs on expofure to the air ; hence 
 morter and cements (q) : A large quantity of water impairs or deftroys this 
 
 property. 
 
 colla, melted with an equal quantity of fixt 
 Alcaline Salt, yielded a Glafs of a fine yel- 
 low colour, probably from fome admixture 
 of ferrugineous matter : the calcareous 
 
 Earth, like common Lime, formed with 
 twice its weight of the Salt only an opake 
 
 whitifh mafs.— Eight ounces of Ofteo- 
 
 colla entire, diftilled in an earthen retort by 
 a ftrong fire, gave two drams of an empy- 
 reumatic volatile Alcaline Spirit : in diftil- 
 lation with Oil of Vitriol, no other than 
 meie phlegm was obtained. 
 
 $ 
 
 (q) Morter and Cements .] Lime made into 
 a pafte with water alone, acquires on ex- 
 pofure to the air fome degree of hardnefs, 
 which feems to be proportionable to that of 
 the original Earth or Stone which the Lime 
 was made from; the Chalk Limes remain- 
 ing foft and crumbly, whilft thofe prepared 
 from Marble become notably hard. If 
 either of them be mixed with glutinous li- 
 quors, as Milk, Blood, Solution ©f Gum, 
 or beat with Cheefe foftened by boiling in 
 Water, they become harder than by them- 
 
 felves. 
 
Earths a 72 d Stones. 15 
 
 property. The vapour which arifes during the extindlion, collected by diftil- Q 4 Lime. 
 lation, proves a liquor of a very Angular kind. It changes Syrup ofViolets — / 
 
 green, and being mixed with Solution of Sublimate throw's down an orange s,n § ular S D‘ 
 yellow Precipitate 5 as if the (Milled Spirit was not only alcaline, but a fixed t ; n fti on . 
 Alcali : it precipitated alfo Solution of Sulphur made in Alcalies, as if it was 
 an Acid. In flaking a pound and a half of Quick-lime, an ounce of this 
 liquor was collected. 
 
 The quantity of Lime difioluble in water is much greater than is generally Qu ant j t y dif- 
 fuppofed. In the common method of making Lime-water, with only a fmall folubleinwa- 
 proportion of liquor, the Lime loies little; but if the refiduum be repeatedly ter - 
 boiled in large quantities of frefh water, alrnoft half the Lime will at length be 
 diflblved (r). 
 
 Lime-water turns Syrup ofViolets green; added to Solution of Subli- Agreement of 
 mateQ), throws down a yellow Precipitate ; unites with Oils into a femifapo- L -[^^y at p r 
 naceous mafs ; diflolves Sulphur into a red Liquor. In thefe properties it VvlU '■ aies » 
 agrees with fixt Alcaline Lixivia ; there are others in which it as remarkably 
 differs from them. Alcalies mixed with Lime-water, precipitate the Lime and difagree- 
 from it: on expofure to the air, the Lime feparates fpontaneoufly, arifing in m£ nt. 
 crufts to the furface : in clofe veffels this feparation does not happen. Though 
 the Lime in fubftance fuftains the mod intenfe fires without diminution of its 
 weight; the part which diflolves in water, is, upon boiling the liquor, totally Volatilized. 
 
 diflipated 
 
 felves, and in a fhorter time : hence the ufe Quick-lime expofed to the air, unmoift- 
 of thefe compofitions for joining cracked ened, falls by degrees into Powder, and 
 Glades, &c. Lime mixed with Sand, or lofes its activity: if kept moiftened with 
 other hard flony bodies in coarfe Powder, Water, it in great meafure retains its acri- 
 forms a concrete ftill harder, and whofe mony, and its peculiar qualities, for years, 
 hardnefs is increafed by length of time ; 
 
 whence in part the remarkable induration of (s) Lime-water precipitates Mercury Subli - 
 the morter of ancient buildings. With mate.] It has been prefumed that Lime- 
 Sand or Flint in fine Powder, it did not water would precipitate all the Metals, but 
 feem to grow harder than by itfelf : nor did experiment {hews the contrary. Dr. Brandt 
 any of the Earths of the other claftes fenfi- obferves, in the Swedilh Tranfadlions for 
 bly improve its confidence. the year 1749, that neither Gold, Silver, 
 
 Tin, or Copper are precipitated by it ; that 
 
 (r) Lime with Water.] This property of Iron is not precipitated at all from the ni- 
 Quick-lime, of impregnating a very large trous or marine Acids, and but imperfedfiy 
 quantity of Water, has been remarked alfo from the Vitriolic; that Quickfilver dif- 
 by Dr. Alfton, and confirmed by a number folved in Aqua fortis, falls in part upon the 
 of experiments, in a Diftertation upon addition of the calcareous liquor, but that a 
 Quick-lime. He finds that about one third part ftill remains fufpended, precipitable by 
 of the Lime difiolves ; and that this re- an Alcaline one. He found that even 
 quires for its Solution feveral hundred times Quick-lime in fubftance did not totally pre- 
 its own weight of Water. cipitate metallic bodies : A quantity of frefh 
 
 If the indifioluble part be calcined afrefh, burnt Quick-lime having been added to a 
 it impregnates Water in the fame manner as Solution of Silver, and the liquor after due 
 at firft ; and by repetitions of the calcina- digeftion poured oft" clear and palled through 
 tion, may at length be almoft wholly dif- a filter, common and Alcaline Salts ftill 
 folved. On expofure to the air, the Lime threw down a Precipitate, which yielded on 
 feparates from the Water, and proves infi- reduction near one fixth of the original 
 pid like the crude Earth or Stone : by a frefh quantity of Silver diflolved. 
 calcination it becomes Quick-lime again. 
 
1 6 
 
 Li me. 
 
 Artificial Sc- 
 iences. 
 
 ritofSal Am- 
 jroniac with 
 Quick- lime. 
 
 A concrete. 
 Salt obtained 
 from it. 
 
 Volatile Salts 
 deftroyed by 
 Lime. 
 
 E a -r t h s and Stones. 
 
 difTi paced in the air along with the watery vapour. Solution of Sulphur made 
 by Quick-lime, on being kept for a length of time in a warm room, yields 
 Cryftalline Concretions, of the Selenitic kind, not diffoluble in water (/). 
 
 Quick-lime, mixed with Sal Ammoniac, immediately difengages its volatile 
 Alcali, without the application of any heat. But it produces at the fame 
 time a remarkable change in the Alcali itfelf; which, when extricated by 
 Quick-lime, never aflumes a folid form, but proves an extremely fubtile Vola- 
 tile Spirit, much ftronger and more penetrating in fmell, and for fundry bo- 
 dies a more powerful menftruum, than that prepared with fixt Alcaline Saits : 
 the Spirit made with Quick-lime does not coagulate, like the other, with recti- 
 fied Spirit of Wine, and hence is preferable as an ingredient in thofe compofi- 
 tions where Alcaline and vinous Spirits are mixed ; nor does it effervefce con- 
 fiderably with Acids, though it precipitates molt metallic folutions made in 
 them. 
 
 Though the volatile Alcali is in this fpirit highly attenuated and fubtilized 
 into a fluid ftate; it is ftill recoverable again in its proper folid form. If the 
 fpirit be iaturated with the Acid of Sea-Sa!t, the liquor duly evaporated and 
 let to fhoot, Cryftals of true Sal Ammoniac will be obtained : and if from 
 thefe we extricate the volatile Alcali by means of Chalk or of fixt Alcalies, it 
 will now concrete into a folid mafs. During the faturation of the fpirit with 
 the marine Acid, a ftrong fetid fmell arifes. 
 
 Zweifer relates, and Stahl has borrowed the obfervation from him, that vo- 
 latile Salts are totally deftrudtible by Quick-lime. I have made fundry trials 
 for determining this point; and found, that with Quick-lime in fubftance, the 
 deftruftion fcarcely fucceeds : for fotne Spirit of Sal Ammoniac having been 
 diftilled no lefs than twenty times from unflaked Lime, a volatile fpirit was 
 obtained to the lafl. By Lime-water on the other hand, the volatile Alcali was 
 quickly deftroyed : a dram of pure Volatile Salt being added to two quarts of 
 Lime-water, much, but not all, of the volatility was loft, and great part of 
 the Earth of the Lime was precipitated : the mixture being digefted, commit- 
 ted to diftillation, and all the volatile part drawn off; the diftilled fpirit, 
 mixed with frefti Lime-water, occafloned no further precipitation, and no 
 longer difcovered any degree of volatility. 
 
 Some 
 
 ( t ) Lime with Acids.'] The Selenitic Cry- 
 ftals, here obtained, were produced from 
 the Lime combined with the Acid of the 
 
 Sulphur : See p. 8. The fulphureous 
 
 or vitriolic Acid, poured upon Quick-lime 
 in fubftance, unites with it far more readily 
 than with the Lime-ftone or Chalk : it dif- 
 folves very little of the crude Earth or Stone, 
 and fcarcely lofes any of its acidity : whilft 
 by Quick-lime, if the due proportion is hit, 
 the whole of the Acid is inftantly abforbed, 
 and the liquor left infipid : The concretes, 
 which the Earth in both ftates forms with 
 the Acid, are the fame, a kind of Gypfum 
 
 or Selenites The other Acids perfectly 
 
 diiTolve Quick-lime, as they do the crude 
 
 Earth, but without effervefcence. The 
 Solution made in the marine Acid coagu- 
 lates with Alcaline Lixivia, and with the 
 Vitriolic Acid ; changes the colour of Syrup 
 of Violets to a green, and hence has been 
 miftaken for an Alcali ; and unites with ex- 
 prefl’ed Oils into a butyraceous fubftance : 
 infpiflated, it yields an highly penetrating 
 faline mafs, which deliquiates in the air, 
 diiTolves in rectified Spirit of Wine, flows in 
 a fmall heat, and does not part with its 
 Acid in a ftrong one : if the matter be in- 
 cruftated on iron-rods and ftruck upon, it 
 fparkles and appears luminous through the 
 whole extent of the ftroke. 
 
Earths and Stone s« 
 
 1 7 
 
 Some have pretended to extrail a Salt from Lime, that fhould difTolve theQ^L i m e«’ 
 
 human Calculus. Dr. Cyprianus, in London, worked on this fubjed for fix t — ' 
 
 years; and I profecuted the inquiry under his infpedion, for three years Salt of Lme.c 
 longer *, purfuing all the hints of Helmont, Paracelfus, and others, but with- 
 out fuccefs. Mofl: of the cryftalline concretes obtained from Lime, are rather 
 earthy, ftony, and felenitic, than faline : And when we gain any thing that is 
 truly faline and lbluble in water, a further examination difcovers that it is 
 chiefly adventitious, and as rarely any thing of the Lime in it. Two papers 
 oh the Salt of Lime, by Mr. du Fay, may be feen in the French memoirs 
 for the years 1724 and 1732 (u). Dr. Pott has given fome curious experi- 
 ments on the folution oi Lime in Spirit of Nitre, in the Mifcellanea Beroli- 
 nenfia (x). 
 
 Quick-lime is employed for many confiderable ufes in chemiftry and theUfescfLime. 
 chemical arts ; as in the redification of Mait-Spirits, empyreumatic Oils, and 
 volatile Salts, from its property of imbibing and detaining grofs Oils ; in 
 the fmelting of fulphureous and arfenical Ores (j), from its abforbing thofe 
 
 volatile 
 
 { u ) Salt of Lime.] On evaporating Lime- 
 water, a fmall portion of faline matter com- 
 monly remains: This has been fuppofed an 
 eflential part of the Lime ; the principle on 
 which its adivity as a menftruum depends. 
 But experiments have fhewn, that this fub- 
 ftance has nothing of the diffolving power of 
 Lime-water : That it is different in diffe- 
 rent Limes, being fometimes vitriolic and 
 fometimes marine : And that the ftrong 
 and pure Lime-water, made from Lime 
 once elixated and calcined again, leaves no 
 faline matter at all. 
 
 (x) Experiments on Lime and Spirit of 
 Nitre.] The more remarkable of thefe ex- 
 periments are as follows. Concentrated 
 
 Spirit of Nitre, poured upon heated Quick- 
 lime, diftolved it into a blood-red liquor ; 
 which mixed with half its quantity of the 
 phlegmof Spirit of Nitre, yielded in diftillati- 
 on an acidulous oily phlegm, condenfing like 
 Spirit of Wine into Striae ; fucceeded by a 
 fimilar ftriated Spirit, fomewhat more acid, 
 in white fumes. The remainder, now of 
 the confidence of Honey, being further 
 urged, gave over a highly corrofive Acid, 
 in red vapours. The Caput Mortuum was 
 auftere, bitterifh, and fomewhat ftyptic ; 
 and could not be made to appear luminous 
 in the dark, as Chalk does when treated in 
 the fame manner. 
 
 The oily phlegm, boiled on frefh parcels 
 of the Honey-like mafs till it had loft both 
 its oilynefs and acidity, yielded on evapora- 
 
 tion an elegant Salt, of a bitterifh, nitrous, 
 not difagreeable tafte, which taken in a gouty 
 cafe procured a gentle diaphorefis, and a co- 
 pious difcharge by urine. The corrofive red 
 fpirit being poured to this Salt, and the liquor 
 evaporated, a fine Nitre was obtained, which 
 deflagrated more quickly than common Nitre*, 
 
 The fpirit became ftronger and more 
 corrofive by repeated cohobations on the 
 Caput Mortuum. At the third cohobation, 
 it appeared of an oily nature, and proved 
 oiJy to the touch : the red fumes, tranfpir- 
 ing through a crack in the luting, took fire 
 from a candle. Some fine Silver having 
 been diffolved in the cohobated fpirit, the 
 liquor diftilled off, and the dry matter kept 
 melted for fome time ; the mafs when cold, 
 looked blue : the diftilled liquor being co- 
 hobated on this mafs, and drawn off again, 
 the dry remainder appeared tinged through- 
 out of a beautiful, deep ultramarine blue,: 
 on a third cohobation, the matter grew 
 whitifh, and at every fucceeding one whiter 
 and whiter, till at length no bluer.efs re- 
 mained The fpirit, let in digeftion with- 
 
 out addition, lets fall a notable quantity of 
 a dark brown unfufible Powder ; which is 
 probably a part of the Lime that had been 
 volatilized by the Acid. Mr. du Hamel 
 obferves, that Quick-lime is by this Acift 
 almoft totally volatilized, arifing with it in 
 diftillation in a liquid form. 
 
 (}) Quicklime in the fmelting of fulphureous 
 Ores.] It is commonly fuppofed that Quick- 
 > lime 
 
i 8 Earths and Stones. 
 
 Q^Lt m e. volatile fukftances, which would difiipate a part of the metal ; in the making 
 
 v- — , ) of Sope, for increafing the activity of Alcaline Salts j in dying, particularly 
 
 with Indigo, idc. 
 
 CLASS III. Gypseous Earths W Stones. 
 
 Earths or foft Stones , — reducible by a moderate fire into an infpid Calx, 
 which forms with water a tenacious Pajle , and which by Jironger calcina- 
 tion lofes that property — in their natural jlate not aided upon by any 
 Acid ; — becoming Joluble in Acids , and fmilar to Quick-lime^ by calcination 
 in contain with the fuel. 
 
 L LAPIS SPECULARIS. 
 
 T H E Lapis Specularis or Glacies Maria is a tranfparent concrete, commonly 
 found in pretty large maffes, which may be eafily fplit into a number 
 of thin plates or leaves, fometimes fo broad as to be uled for lanterns. Its 
 foliaceous texture has occafioned it to be often confounded with Talc (2) ; from 
 which it may be readily diftinguilhed, by the tranfparency of the entire mafs 
 as well as of the fingle leaves ; by its glafly rather than undtuous fmoothnefs, 
 .and rather a vitreous brightnefs than a filver hue ; by the mafs being eafily 
 pulverable, and eafily calcinable in the fire. 
 
 n. s E» 
 
 lime abforbs Sulphur from all the metals; 
 and hence fome have prefumed that the ad- 
 dition of Quick-lime to fulphureous Ores 
 would fupply the place of calcination. This 
 does not appear however to obtain. When 
 Copper is blended with Sulphur and a little 
 iron, as in mod of the rich Copper Ores ; 
 Quick-lime abforbs and vitrifies with the 
 Iron, leaving the Copper fulphurated as at 
 firft. Sulphurated Iron that holds no Copper, 
 melts with Lime into one uniform mafs, 
 without any feparation at all : and when 
 
 a large quantity of Iron is blended with 
 Sulphur and Copper, the effect is the fame ; 
 Quick-limeunitingequally with all the three. 
 Dr. Brandt obferves that both Copper and 
 Iron Ores, thoroughly calcined, melt eafily 
 with Quicklime into Glafs ; probably from 
 the adlion of the calcareous Earth on the 
 ftony matter of the Ore, (fee page 10.) for 
 with pure calces of thofe metals it refufes to 
 melt. Quick-lime is in general much more 
 difficult of fufion, both with earthy and 
 faline bodies, than the calcareous Earth or 
 Stone in its natural Hate. 
 
 (z) Confounded with Talc.} The Powder 
 
 which Mr. Reaumur received from China 
 under the name of Petuntfe as one of the in- 
 gredients in the Chinefe ware, and which, 
 from fome flaky or ftrawy particles obferved 
 in it, he calls Talc, appears to have been 
 an Earth of this kind ; fome of our Gyp- 
 fums exhibiting a like ftrawy texture, 
 whence they are diftinguifhed by the name 
 of Gypfurn Striatum. He fays this Chinefe 
 Talc baked with Flints into a fubftance re- 
 fembling Porcelane ; and that Talcs found 
 in France did the fame ; a property belong- 
 ing to all the gypfeous Earths, but to none 
 
 of the true Talcs The other ingredient 
 
 in China-ware, called by the Chinefe Kaolin , 
 is faid by the fame author to be a fpecies of 
 Flint ; but from its forming with water a 
 mafs tenacious enough to be made into the 
 loaves in which it was brought over, it 
 fhould feem rather to be of the argillaceous 
 kind. 
 
 Thefe l'ufpicions are confirmed by fome 
 experiments of Mr. Scheffer’s (in the Swe- 
 dilb Tranfa£lions for the year 1753) upon a 
 fpecimen of Petuntfe obtained from China. 
 It was a glittering, femitranfparent, flaky 
 mafs, like the Lapis Specularis , of a light 
 
 green; fh 
 
Earths and Stones* 
 
 II. SELENITE S. 
 
 THE Selenites refembles in appearance fometimes the Lapis Specularis s Selenit. 
 
 and fometimes Cryftal ; but wants the leafy llruCture of the one, as well — .? 
 
 as the hardnefs of the other. It is found both in large and in fmall mafles, 
 always tranfparent, but not always free from cloudinefs j and fometimes of a 
 yellowifh tinge. It eafily calcines into Gypfum or Plafter-of-Paris (a). A 
 portion of felenitic matter is contained in fundry waters, as thofe ofPyrmont, 
 and feveral of the mineral waters of France, as appears from the analyfes of 
 them related in the memoirs of the French academy. 
 
 III. BOLOGNIAN STONE. 
 
 ^HIS Stone has become remarkable from its property of affording aPhof-BoLOGN. 
 
 phorus by calcination, firft difcovered by a llioemaker, Vincenzo Cafci- >_ — — _ » 
 arolo(^). The Stone is found in the hill called Monte di Paderno about 
 
 three 
 
 greenifh grey colour, and remarkably heavy. 
 It was not aCted upon by Acids : iri the 
 fire, it burft and fell in pieces, and calcined 
 into a white Powder, interfperfed with a 
 red ferrugineous matter. Calcined in con- 
 tact with the fuel, it emitted firong fulphu- 
 reous vapours like the other Gypfa, and 
 became quite white, confiderably firm and 
 coherent, and femitranfparent. A mixture 
 of the powdered Stone with tobacco-pipe 
 Clay yielded a Porcelane not fully fo white 
 as theChinefe: This imperfection he attri- 
 butes to the Clay, which when burnt hard, 
 is never of fuch whitenefs as the lefs burnt 
 tobacco-pipes. 
 
 (a) Calcines into Plafter-of-Paris.] The 
 Stones from which Plafter-of-Paris is ufual- 
 ly prepared, are of a granulated ftruc- 
 ture and femitranfparent ; fometimes com- 
 pact and moderately hard, fometimes lax 
 and crumbly. The calcination is performed 
 with a heat fomewhat below ignition : the 
 Stone feems as it were to liquefy and to boil, 
 emits aqueous vapours, and at length fub- 
 fides into a foft Powder ; the mark of the 
 calcination being completed. The Powder, 
 made into a Pafte with water, becomes 
 quickly a confident mafs, of no great haid- 
 nefs, but fonorous, and of a fmooth fur- 
 face: hence its ufe as cement, and for 
 
 taking off impreftions. The matter ex- 
 pands in becoming folid, receives no increafe 
 
 D 
 
 but rather a diminution of its hardnefs on 
 expofure to the air, readily imbibes water a 
 but is not aCted on by any Acid. The fur- 
 ther the Earth has been calcined, the Pafte 
 hardens the more flowly, and proves the 
 lefs tenacious, but more durable. Kunckel 
 gives feveral receipts for tinging Plafter of 
 a variety of colours, by ufing, inftead of 
 plain water, coloured decoCtions, as of red 
 Saunders, Brazil-wood, Saffron, £sV. and 
 fays the hardnefs may be improved by dif- 
 folving a little Gum, or rather Ifinglafs, in 
 the liquor. 
 
 The gypfeous Earths calcined by a ftrong 
 fire, in immediate contact with the burning 
 fuel, emit fulphureous vapours, and become 
 Quick-lime. The principle they have loft 
 in this operation is the vitriolic Acid ; of 
 which it is a diftinguifhing character, to 
 form Sulphur with inflammable matters. 
 The calcined Earth, combined afrefh with 
 that Acid, regenerates Gypfum again : and 
 the common Quick-limes, or unburnt calca- 
 reous Earths, yield with the fame Acid the 
 fame compound. 
 
 [b) Bolognian Stone,] Mr. Margraf firft 
 obferved that this property is common to 
 the other Gypfums when pure from metal- 
 lic or other heterogeneous admixtures ; and 
 that the artificial Gypfums fucceed equally 
 with the natural. For preparing this Phof- 
 phorusin perfection he directs the Stone to 
 2 be 
 
20 Earths and Stones, 
 
 Bologn. three mites from Bologna-, as alfo on the Piedalbino at the foot of the Alps, 
 
 v — — — > ' about eight miles from the fame city, it is met with chiefly after heavy rains ; 
 
 by which the loofe Earth is wafhed off, and the Stone left bare. It is of vari- 
 ous figures and fizes : fome mafles weigh no lefs than eight pounds; butthofe 
 of an ounce or two anfwer beft for making the Phofphorus. 
 
 Phofpherus. The Phofphorus is thus prepared. Some of the fineft Stones are reduced into 
 a fubtile Powder in a brafs mortar ; and entire Stones, well cleaned or filed on the 
 farface, and moiftened with Spirit of Wine, are rolled in this Powder, and the 
 procels leveral times repeated, till they are all over coated with the Powder ; af- 
 ter which, the Stones are calcined among burning Charcoal in a moderate wind- 
 furnace. When grown cold, they are commonly cleared from the powdery 
 cruft, and wrapt up in Cotton. The principal cautions in. the operation are*, 
 that no Iron inftruments be made ufe of in the whole procefs that the coals 
 be not too large, dufty, or foul ; and that the Stones be fuffered to grow 
 thoroughly cold before they are taken out of the furnace. 
 
 This Phofphorus, like that of Balduin, appears luminous in the dark after 
 being expofed for a time to the fun’s light : if made in perfe&ion* expofure for 
 a few minutes is fufficient: The inferior kinds require fometimes an hour or 
 more. It proves more luminous when expofed in a fhady place, than to the 
 diredl rays of the fun : Hot funfliine is apt to deftroy its power,. It has been 
 diftinguiflhed by different names ; Phofporus bononienfis 9 , italicus , mineralis ; lapis 
 lucidus or luminofus ; ignis frigidus ; fpongia foils. 
 
 be pulverifed in a glafs -mortar, and the Vitrification of gypfeous Earths. ~] The gypfe- 
 Powder made up into thin cakes with mu- ous Earths flow readily with Borax into 
 cilage of Gum-tragacanth : A good wind- yellow Glafs ; with Sal Mirabile into a fine 
 furnace being filled to about three-fourths its greenifh yellow ; but do not perfectly vitrify 
 height with fmall pieces of Charcoal, the with other Salts,, unlefs the quantity of Salt- 
 cakes, thoroughly dried, are to be fpread is large, and the fire extremely ftrong. 
 upon the unlighted pieces at top, and the Mixtures of them with argillaceous Earths 
 furnace filled up with more Charcoal : After vitrify without any faline addition, efpeci- 
 the fire has burnt out, the cakes are found ally if expofed to the immediate aftion of 
 on the grate, and may be eafily freed from the fire. They do not melt with any pure 
 the afhes that adhere, by blowing. The Earth of the other clafles ; nor do they 
 light of thefe mafles is fometimes white, bake or cohere in the fire with any but the 
 fometimes like that of a burning coal : A Cryftallinb.. 
 fecond calcination generally increafes their 
 luminous quality. 
 
 CLASS 
 
Earths and Stones 
 
 21 
 
 CLASS IV. Argillaceous Earths and Stones. 
 
 Earths forming with water a tenacious Pafte> or foft Stones ; — burning 
 hard (c) ; — corroded by flrong cobiion in the concentrated mineral Acids , 
 but not abied on by moderate digefion. 
 
 L BOLE S. 
 
 T HREE kinds of Boles are ranked among medicinal Earths, Armenian, 'Bol.Arm. 
 
 red, and white. That met with in the fhops under the name of Arme- > — . — ^ 
 
 nian is not the produce of Armenia or any of the oriental countries, but, like 
 the others,, of different parts of Europe, as Bohemia, Silefia, Saxony, Hun- 
 
 8 at 7» 
 
 city. Frefii Clay, divided by a due propor- 
 tion of this Powder, proves lefs tenacious 
 than by itfelf, not flicking to the hands, 
 though cohering fufficiently together : It 
 {brinks lefs in drying, is lefs apt to crack, and 
 lefs fufceptible of injury from alternations 
 of heat and cold ; but at the fame time lefs 
 folid and compact. Confiderable differences 
 are obferved in thefe refpeCts, not only ac- 
 cording to the quantity of the dividing mat- 
 ter, but according as it is in finer or coarfer 
 powder. 
 
 Veffels made with a moderate proportion 
 of fine Powder, as half the weight of the 
 Clay, are compaCt and folid, but ftill very 
 liable to crack from fudden heat or cold. 
 
 Thofe with a larger proportion, as twice or 
 thrice the quantity of the Clay, are free 
 from that imperfection, but fo friable as to 
 crumble betwixt the fingers. Nor does 
 there appear to be any medium betwixt a 
 difpofition to crack or to crumble ; all the 
 compounds made of Clay and fine Powders, 
 having one, or the other, or both imper- 
 fections. — Coarfer Powders, about the fize 
 of middling Sand, form with an equal weight 
 of Clay, compounds fufficiently folid, and 
 much lefs apt to crack than the mixtures 
 with fine Powders: Two parts of coarfe 
 Powder and one of Clay, prove moderately 
 folid, and but little dilpofed to crack : A 
 mixture of three-parts and one, though 
 heated and cooled fuddenly does not crack 
 at all, but fuffers very fluid fubftances to 
 tranfude ; folidity, and refiftance to quick 
 viciffitudes of cold and heat, feeming here 
 alfo to be incompatible. 
 
 Different earthy matters, employed for 
 
 dividing 1 ; 
 
 (c) Tenacious Pajle— burning hard.] Thefe 
 are the properties of Clays on which their 
 utility depends as the bafis of Earthen- 
 wares. When foftened with water they 
 prove fo duCtile and cohefive, as to be 
 formed with eafe into any figure ; and ex- 
 pofed afterwards to the fire, they acquire a 
 degree of hardnefs, which becomes greater 
 and greater in proportion to the vehemence 
 and continuance of the heat. 
 
 Pure Clay, foftened to a due confidence 
 for being worked, not only coheres toge- 
 ther, but flicks to the hands : in drying it 
 contracts, an inch or more in twelve ; and 
 hence is very liable to crack, unlefs the 
 exficcation is performed exceeding flowly : 
 in burning, it is fubjeCt to the lame incon- 
 venience, unlefs very gradually and equally 
 heated. When thoroughly burnt, if it has 
 efcaped thofe imperfections, it proves folid 
 and compaCt, and fo hard as to ftrike fire 
 with Steel : Veffels made of it are not pe- 
 netrated by any kind of liquid, and refift 
 Salts and Glaff'es brought by fire into the 
 thinneft fufion, excepting thofe which cor- 
 rode and diffolve by degrees the Earth itfelf, 
 as Glafs of Lead ; and even this penetrat- 
 ing Glafs, there is fcarcely any other Earth 
 that refills fo long : But in counterbalance 
 to thefe good qualities, they want the white- 
 nefs and femitranfparency required in orna- 
 mental vafes ; and cannot be heated or 
 cooled, but with fuch precautions as can 
 rarely be complied with in common bufi- 
 nefs, without cracking or flying in pieces. 
 
 Clay that has once been expofed to any 
 confiderable heat, and afterwards reduced to 
 Powder, has no longer any degree of tena- 
 
22 Earths and Stones. 
 
 Bol. Arm. gary, Tranfylvania, France, Norway, (3c. The French employ chiefly the 
 — v — u Bole of Blois. We need not be folicitous about the particular place where any 
 of the Boles have been dug, provided they are pure and of a good quality. 
 
 i. Bole 
 
 dividing Clay, agree nearly in thefe general 
 mechanical effeAs : But they differ confi- 
 derably in other refpedts, according to the 
 chemical qualities of the particular Earth, 
 (i.) Pure Clav, mixed with pure Clay that 
 has been burnt, is no other than one iimple 
 Earth, and is neither to be melted, or foft- 
 ened, or made in any degree tranfparent, 
 by the mod intenfe fires. (2.) Mixtures of 
 Clay with gypfeous Earths burn whiter than 
 Clay alone: In certain proportions, as 
 two parts of Clay to three of Gypfum, they 
 become in a moderate fire, femitranfparent j 
 and in a ftrong one they melt. (3.) Cal- 
 careous Earths, in fmall proportion, bake 
 tolerably compact and white ; and added 
 to other compofitions, feem to improve 
 their compadtnefs. If the quantity of the 
 calcareous Earth nearly equals that of the 
 Clay, the mixture melts into a yellow 
 Glafs : If it confiderably exceeds, the pro- 
 duct acquires the qualities of Quick-lime. 
 (4.) Veffels made from Clay and Sand, in 
 whatever proportion, do not melt in the 
 ffrongeft fire ; but they fometimes bend or 
 foften, fo as to yield to the tongs : Glaffes, 
 in thin fulion, penetrate them, by diffolving 
 the Sand : If gypfeous or calcareous Earths 
 are urged in fuch a crucible with a vehe- 
 ment heat, the veffel and its contents run 
 all into one rnafs. In moderate fires, thefe 
 veffels prove tolerably compact, and retain 
 mod kinds of Salts in fufion : But they are 
 liable to crack, efpecially when large, and 
 do not longfuftain melted metals, being apt 
 to be burft by their weight : Such are the 
 Heflian crucibles. (5.) Flint forms whiter 
 compounds than Sand, and hence is made 
 ufe of as the dividing ingredient in the com- 
 mon white wares. (6.) Talc yields very 
 compact mafies, which freely ftrike fire 
 with Steel, and never melt or foften. 
 (7,) Mixtures of Clay and Black-lead 
 (which feem a fpecies of Talc) are not 
 liable to crack from alternations of heat and 
 cold, but extremely porous : Hence Black- 
 lead crucibles anfwer excellently for the 
 melting of metals, and Hand feveral re- 
 peated fufions 5 whilft Salts, flowing thin. 
 
 tranfude through them, almoft as water 
 through a fieve: Sulphureous bodies, as 
 Antimony, corrode them. Thefe mixtures, 
 when only moderately burnt, prove fo foft 
 as to be cut with a knife ; a property for 
 fome purpofes very valuable : Thus a 
 
 door, &c. may be cut in a Black-lead pot, 
 fo as to make it a commodious portable 
 furnace. 
 
 Pure Clay, foftened with water and in- 
 cruftated on earthen veflels that have been 
 burnt, does not adhere to them, or feales 
 off again upon expofure to the fire ; applied 
 to unburnt veflels, it adheres and incorpo- 
 rates. Divided Clay unites with them in 
 both ftates. — Vitreous matters, melted in 
 veflels of pure Clay adhere fo firmly as not 
 to be feparated : From veffels of divided 
 Clay they may be knocked off by a ham- 
 mer. 
 
 The faline fubftances which promote the 
 fufion of Clay, (befides the common fluxes of 
 all the Earths, Alcali and Borax) are chiefly 
 Arfenic fixed by Nitre, and the fufible Salt 
 of Urine; both which have little effect on 
 the other Earths though mixed with them 
 in a large proportion. Nitre, which readily 
 brings the cryftalline Earths into fufion ; 
 and Sal Mirabile and Sandiver, powerful 
 fluxes for the calcareous, do not perfedlly 
 vitrify with Clay. Burnt Clay does not 
 differ in thefe refpedls from fuch as has not 
 been burnt ; nor in that Angular property 
 of vitrifying with gypfeous and calcareous 
 Earths without any faline or metallic addi- 
 tion : The utmoff vehemence of fire feem- 
 ing to deftroy only its ductility, or that 
 power by which it coheres when pulverifed 
 and moiftened with water. It is faid that 
 Clay, added in the compofition of common 
 Glafs, makes it tougher and lefs apt to 
 crack. 
 
 The experiments from which the forego- 
 ing general refults are drawn, were made 
 with the tougher kind of tobacco-pipe Clay, 
 which appears to be one of the pureft of the 
 Earths of this clafs. There is a great va- 
 riety of Clays, differing in the degree of 
 tenacity of the clay itfelf, as well as in the 
 
 admixture 
 
Earths and Stones, 23 
 
 I. Bole Armenic is of a pale colour, between red and yellow, fmooth and Bol. Arm, 
 flippery to the touch, fomewhat gloffy, pure from Sand or any perceptible t — -y- — . > 
 gritty matter. It readily crumbles betwixt the fingers, and adheres to the Defcri P tl0n> 
 tongue. Softened with water, it forms a fmooth Pafte : diluted with a larger 
 quantity of water, it remains for a confiderable time fufpended. 
 
 This Earth contains, befides the purely argillaceous, a fmall portion of one Examined by 
 of a different clafs, which is extracted from it by Acids. In each of the fol- Adds, ta’c. 
 lowing experiments were employed fixty grains of the Bole, (i.) Spirit of 
 Vitriol diffolved eight grains: The folutionwas clear; the dried refiduum grey. 
 
 (2.) Spirit of Nitre diffolved five grains : The folution appeared (lightly yel- 
 lowi/h ; the refiduum yellowilh grey. (3.) Spirit of Salt, feven grains : The 
 folution not green as Ettmuller relates, but of a Gold yellow; the refiduum 
 of a pale Sulphur yellow. (4.) Diftilled Vinegar diffolved but two grains : The 
 folution was clear, but tailed bitterifh, whiift thofe made in the mineral Acids 
 were fweetifh : The refiduum unchanged. (5.) Rhenifh Wine had the fame 
 effedt as diftilled Vinegar, except that the liquor proved in tafte lei's bitter. 
 
 (6.) Frefh Citron juice diffolved five grains : The liquor was clear, thickifh, 
 and had a kind of vitriolic tafte : The refiduum unchanged. (7.) Alcaline Lixi- 
 via, diffolved nothing; but the Bole was found to have abforbed a part of the 
 Alcali, appearing when dried of a darker colour, and weighing fifteen grains, 
 or one fourth, more than at firft. (8.) Spirit of Sal Ammoniac on the other 
 hand diffolved two grains of the Bole : The refiduum unchanged. (9.) Lime- 
 water had no effedt. (10.) Redtified Spirit ofWine took up four grains, with- 
 out occafioning any further alteration. 
 
 Four ounces of Bole Armenic, diftilled in a glafs-retort in an open fire, Examined by 
 yielded three drams of a faline phlegm, which fmelt a little urinous, and filiation, 
 changed Syrup of Violets green. In the neck of the retort was found a little 
 powdery faline matter, which had an ammoniacal tafte, but was in too fmall 
 quantity to be colledted or further examined. 
 
 Bole Armenic, like moft of the other coloured Earths, contains a portion Contains 
 of ferrugineous matter, to which its colour is owing, and which may be fepa- Iron> 
 rated by the magnet after the Bole has been calcined with Oil or other inflam- 
 mable matters. It is likewife impregnated with vitriolic Acid : And hence, and vitriolic 
 when mixed with Nitre or Sea-Salt, it extricates the Acids of thofe Salts in the Aud ’ 
 
 fire : 
 
 admixture of heterogeneous matters. The 
 ileatitic Earths or Stones (fee the following 
 note) are no other than Clays, indurated, 
 or deprived of their mifcibility with water : 
 There are clays of all the intermediate de- 
 grees of toughnefs, from thefe to the vifeid 
 Pipe-clay. The Sturbridge Clay appears 
 nearly a medium betwixt thefe two ex- 
 tremes : Hence it is made into pots, for 
 fuflaining the glafs-houfe fires, without any 
 addition to divide it ; and cannot be work- 
 ed, when mixed with fuch large proporti- 
 ons of untenacious Powders, as the more 
 vifeid Clays require. The loams or brick 
 Earths are mixtures of Clay and Sand ; 
 
 The coloured Clays and loams participate 
 of Iron : Hence many of thefe melt in a 
 ftrong fire without any addition ; both 
 Clay itfelf and mixtures of it with cryftalline 
 Earths being brought into fufion by ferru- 
 gineous calces ; though the fufible mixtures 
 of Clay and calcareous Earths are by the 
 fame ingredient prevented from melting. 
 The bricks made from fome loams, particu- 
 larly the Windfor, are when moderately 
 burnt, remarkably free, fo as to be eafiiy 
 rubbed fmooth, cut, fawed, grooved, c 5c. 
 Hence their ufe in building furnaces, &c. 
 They bear a confiderably ilrong fire ; but in 
 a vehement one, I have often melted them. 
 
24 - 
 
 Earths and Stones. 
 
 > — — 
 
 Medicinal 
 
 ufe. 
 
 Bol. Arm. fire: It was probably by the Acid of the Bole, that the alcaline Salt, in Exp. 7. 
 — ' was abforbed and detained. 
 
 This Earth is employed medicinally as a ftyptic, both internally and ex- 
 ternally •, a virtue which feems to proceed from its ferrugineous impregnation : 
 To the antipeftilential and alexipharmac qualities, for which it has long been 
 celebrated, it has no pretence : And the foregoing experiments fufficiently 
 
 evince, that the abforbent ones, which fome afcribe to it, have no juft founda- 
 tion. It is prepared or purified by wafhing over with water; the pure Bole re- 
 maining fufpended for a confiderable time fo as to be poured off with the li- 
 quor, whilft the fandy or other grofier matter remains behind : After the Bole 
 has fettled from the water, it is moderately dried, formed into rolls or cakes, and 
 afterwards further exficcafed for ufe. Some have condemned this method of 
 purification, as depriving the Bole of a certain central Salt. But this Earth 
 contains nothing that water is capable of extradting : Bole Armenic treated 
 with water, remained undiminifhed in weight; and neither the Bole or the 
 water received any fenfible alteration. 
 
 RedBole. II. The common red Bole is coarfer than the Armenian, and participates 
 — v— more largely of Iron : Hence it is never given internally unlefs to cattle. I 
 Acids ^ exam * ne d m f ame manner as the Armenian ; employing, with each 
 ’ ’ menftruum, fixty grains of the Earth. (1.) Spirit of Vitriol diflolved five 
 
 grains: The Solution tafted like Vitriol of Iron : Its colour was white, that of 
 the remaining Bole brownifh grey. (2.) Spirit of Nitre diflolved ftven grains : 
 The folution was yellowifh, and of a vitriolic tafte ; the refiduum yellowifh 
 brown. (3.) Spirit of Salt diflolved fix grains : The liquor deep yellow, and 
 of a vitriolic tafte ; the refiduum yellowifh white. (4.J Diftilled Vinegar took 
 up but three grains : The liquor clear and fweetifh; the refiduum rather 
 darker coloured than the Bole was at firft. (5.) Citron juice extracted five 
 grains, and left the Bole fomewhat paler : The liquor had an earthy kind of 
 tafte. (6.) Rhenifh Wine diflolved no more than one grain : The remaining 
 Bole unchanged. (7.) A ftrong fixt alcaline Lixivium received no tintture 
 from the Bole, but was in part abforbed by it ; the dried matter weighing 
 twelve grains more than the Earth employed ; its colour was fomewhat darker. 
 (8.) Spirit of Sal Ammoniac diflolved two grains : The liquor was clear; the 
 remaining Bole fomewhat darker. (9.) Lime-water diflolved three grains. 
 (10.) Rectified Spirit of Wine two grains. (11.) Common water had not the 
 leaft effedt. 
 
 Four ounces of red Bole, diftilled in an open fire, yielded two drams and a 
 half of urinous phlegm ; the remaining Bole preferving its original colour. 
 On previoufly digeftingthe Bole with a faturated alcaline Lixivium, fomewhat 
 more of the urinous matter was produced, and the diftilled liquor had a volatile 
 fmell ; an experiment which may deferve further confideration. 
 
 By diftiliati- 
 on. 
 
 W. Bole. III. The white Bole is brought to us ready wafhed and formed into large 
 u.in-y— rolls or cylindric glebes, not of a chalky whitenefs, but rather of an afh co- 
 lour. Formerly it came only from Tufcany or the iflandElva: At prefent 
 it is fupplied chiefly from Norway, the ifland Bornholm, or places nearer home. 
 
 5 i £ 
 
Earths and Stones. 25 
 
 lc differs from the two preceding in containing no manifeft: irony matter, and Bole. 
 
 confequently in wanting their aftringency. It has been recommended as an u — t 
 
 abforbent; but experiments made upon it with Acids fhew that it little de- 
 ferves that character, any more than the other Boles. Some have a method of pearls clean* 
 recovering theluftre of Pearls, efpecially the Scotch ones, by warming them aed. 
 little over the fire, and rubbing them with powdered white Bole. 
 
 Out of fixty grains of this kind of Bole, (i.) Spirit of Vitriol diffolved four White Bole 
 grains : The folution was clear, and had fcarce any vitriolic tafte ; the refiduum examined by 
 grey. (2.) Spirit of Nitre diffolved fix grains: Both the liquor and the refi- Ac ^ 5 ' 
 duum looked yellowifh. (3.) Spirit of Salt, five grains : Both the Menftruum 
 and the Bole unaltered in colour. (4.) Diftil led Vinegar, two grains : The 
 liquor clear, the Bole unaltered. (5.) Citron juice, fix grains: The folution 
 tailed bitterifh ; the Earth looked fomewhat darker. (6.) Rhenifh Wine took 
 up nothing, but fomewhat darkened the colour. (7.) Fixt Alcali was in part 
 retained, as by the other Boles ; increafing the weight ten grains, or one fixth. 
 
 (8.) Spirit of Sal Ammoniac diffolved three grains ; the liquor appeared tinged 
 a little; the Bole fomewhat darker. (9.) Lime-water diffolved two grains ; 
 the liquor clear, the Bole unchanged. (10.) Rectified Spirit of Wine diffolved 
 four grains, and left the Bole unaltered. (n.)Pure diddled water took up 
 three grains ; but the part diffolved gradually fell down again, not in the form 
 of powder, but what is pretty remarkable, in flakes refembling a kind of 
 mouldinefs. 
 
 Four ounces of white Bole yielded in diftillation only one dram and a half 
 of a yellowifh phlegmatic liquor, which fmelt fomewhat empyreumatic, and 
 changed Syrup of Violets green : The Caput Mortuum was grey. 
 
 II. TRIPOLI. 
 
 T HIS Earth, brought perhaps at firft from Tripoli in Barbary, is now'p RIpQLI 
 
 found infeveral parts of Europe ; in the ifland Corfica, Ifchia, at Bayonne, v / 
 
 in Spain, in feverai hills in France, particularly at Poligny near Rennes in Natural Hif- 
 Britany, where it lies in Strata about a foot thick. It is always of a yellowifh tor 7 * 
 colour, commonly about the fhade called an Ifabella yellow, fometimes paler, 
 fometimes deeper, or variegated with darker ftreaks inclining to reddifh. The 
 befl fort is foft and eafily rubbed, yet compadt and not very powdery, free 
 from Sand or Gritt, of no tafte or fmell, and not very heavy. It burns hard chemical 
 like the common potter’s Earth, from which it differs little otherwife in qua- Hiilory. 
 lity, than in being more difficultly vitrefcible. Its principal ufe is for the 
 polifhing of metalline utenfils, optic glaffes, Off. Some have employed it in 
 the diftillation of acid Spirits, but very unfrugally; common Loams and 
 Brick earths being fitter for that purpofe, as well as cheaper. Stahl made 
 ufe of it in an ointment for the itch, which I prepared for him here, and 
 which was compofed of an Amalgam, ground firft: with as much Tripoli as 
 rendered it pulverable, and then mixed with the camphorated white Oint- 
 ment. 
 
 Two ounces of powdered Tripoli, diftilled in a glal's retort in an open fire, 
 yielded at laft two fcruples of a weak Spirit of Salt ; and in the neck of the 
 
 E retort 
 
a 
 
 26 
 
 E 
 
 A R T H S 
 
 ctind Stones. 
 
 Tripoli, retort was found a little blackifh Sal Ammoniac : The refiduum weighed four 
 y — ,j fcruples lefs chan at fiirft. Mixed with Nitre, it extricated the Acid of that 
 Salt, and gave over its own marine Acid ; the diftilled liquor proving an 
 Aqua Regia, and diflolving Gold. Out of fixty grains of Tripoli, Oil of 
 Vitriol diffolved only one grain ; Spirit of Vitriol, two ; Spirit of Salt, three; 
 Spirit of Nitre, live ; and Aqua Regis, eleven. The folutions in the vitriolic 
 and marine Acids were colourfefs : That in the nitrous, yellowiih ; and that 
 
 made with Aqua Regis, of a deeper yellow, the Earth remaining white. 
 Diftilled Vinegar, and fixt and volatile Alcalies, had no effed: But the Cau- 
 ftic fixt Alcali diffolved feven grains. 
 
 III. LAPIS N E P H R I T I C U S. (d) 
 
 Nephrit. THE Lapis Nephriticus is a foft, brittle, opake Stone, not fufceptible of 
 . - 1 a good polifh, fmooth and as it were unduous to the touch, variegated 
 
 Natural Hif- with different colours, among which green is the principal. It is found in 
 iory. New 
 
 (d) Lapis Nephriticus. ] The Lapis Ne- 
 phriticus is a fpecies of the indurated Clays 
 called from their unduofity. Steatite: With 
 thefe it agrees not only in its obvious pro- 
 perties, but likewife in its burning hard, the 
 grand charadcr of argillaceous Earths. Its 
 green colour feems to proceed from Cop- 
 per : Pott relates, that on fufion with an 
 equal quantity of Borax, it yielded a beau- 
 tiful red mafs, refembling an agate, with a 
 grain of Copper at the bottom. It is con- 
 iiderably the hardefi: of the fubftances of 
 this clafs. 
 
 The Steatites, or Sope-rock, is faid to be 
 plentiful in forne parts of England, particu- 
 larly in Cornwall. It 'is in general fo foft as 
 to be eafily cut with a knife, and turned in a 
 lathe. Among the Grifons in Switzerland, 
 it is turned into pots for culinary ufes, by a 
 pointed tool moved round by a mill ; whence 
 the Stone is called Lapis ollaris: It is faid 
 that a great number of thefe velfels are cut 
 out of one mafs, with fuch nicety, that 
 they all fit exadly into one another again, 
 and appear but one ; that they are very dur- 
 able ; and that when cracked, they are 
 joined by Iron wire. The author above- 
 mentioned obferves, that childrens Marbles, 
 and the China figures, are made of Steatitae: 
 And fufpedfs, that the heads, ftatues, and 
 other monuments of ancient artifts, whofe 
 elegance, hardnefs, and durability are the 
 admiration of ours, were cut from fome 
 of the foft fteatitic Earths ; which after 
 having freely yielded to the tool and re- 
 
 ceived the form, acquired from fire the 
 hardnefs of Stones, and were finally embel- 
 lifhed with the polilh which they ftill retain. 
 Thus much is certain, that the Steatitae 
 burn to a great degree of hardnefs, fo as to 
 ftrike fire in abundance with Steel, and bear 
 a fine polilh ; and that the ancients were 
 well acquainted with thefe Stones and their 
 properties. Theophraftus exprefsly menti- 
 ons a Stone Found at Siphne, fo foft as to 
 be ufed by the fculptor and turner, and cut 
 into vefiels for the table, and which when 
 heated and impregnated with Oil became 
 very black and folid. 
 
 The greyifh and pale greenifh Steatitae 
 commonly burn white in an open fire, but 
 in clofe velfiels yellow : The yellow forts 
 burn red, as participating of Iron, which 
 on digeftion in Aqua Regis is extra&ed, 
 and tinges the menftruum yellow. Thofe 
 which are naturally pure from Iron, or have 
 been purified from it by Aqua Regia, melt 
 with twice their weight of fixt Arfenic into 
 a fine yellow Glafs ; and with equal then- 
 weight of Borax, into a greenifh one, not 
 ill refembling the Beryl. With Clay they 
 form a compound extremely hard, and of 
 great whitenefs. Thefe experiments were 
 made by Mr. Pott on the Steatites of Ba- 
 reuth in Franconia, there called Sckzneerjlein y 
 Speckjiein, Meelbafz ; and by me, with the 
 fame fuccefs, on the mattes met with in the 
 fhops under the name of French Chalk, fo 
 called perhaps from their drawing white 
 lines on cloth. 
 
Earths and Stones. 
 
 New and Old Spain, in Swiflerland, Bohemia, and Saxony. From its imaai- Nephrit, 
 nary medical virtues againft nephritic diforders, it has been ranked among The L. — — _•> 
 precious Stones ; but in all its fenfible qualities it is very far removed from thofe 
 of that clafs. It is furprizing that Hernandez, De Boot and others, fhould 
 have referred it even to the Jafpers, the Agates, or the Marbles ; from all 
 which it is extremely and obvioufiy different : Though it has the green fpecks 
 of the Jafpers, it never has their red ones: It wants the hardnefs and com- 
 padtnefs of thofe Stones; and they, the undtuofity or fopinefs of the Nephri- 
 tic. ProfefTor Nebel, in 1733, publifhed a diflertation on a new nephritic 
 Stone: ‘But this, from his own account of it, and the fpecimen feht me, ap- 
 pears to be an entirely different one ; having neither the green colour, the 
 fpecks, the fopinefs, nor any of the characters of the Lapis Nephriticus. 
 
 On examining the nephritic Stone by Menftrua, nothing very remarkable Examined By 
 was obferved ; except that a part of it was extracted by all Acids, and by Menftrua, 
 fome a very confiderable one. Out of fixty grains, diflilled Vinegar diflblved 
 three, Oil of Vitriol, feven, Spirit of Vitriol fourteen. Spirit of Nitre fixteen. 
 
 Aqua Regia eighteen, and Spirit of Salt twenty. The Spirit of Salt acquired 
 a greenifh yellow Tincture, Aqua Regia a Gold yellow, Oil of Vitriol a dark 
 brownifh ; the other Acids remained colourlefs. Both the marine Acid and 
 Aqua Regia left the undiffolved Earth whitifh, the nitrous Acid greyifh, the 
 diluted vitriolic Acid brownifh yellow, the concentrated light reddifh brown ; 
 the acetous, unchanged. 
 
 An ounce of powdered Lapis Nephriticus, diflilled in a retort in an openly diftiilatl^ 
 fire, yielded about a dram and a half of phlegm, which had a penetrating on. 
 empyreumatic fmell, and made no change in the colour of Syrup of Violets, 
 
 On diftilling four ounces, I had an appearance of an adtual empyreumatic 
 Oil ; with a faline matter, which was found to be Sal Ammoniac ; for it effer- 
 vefced with Oil of Vitriol and emitted fumes refembling thofe of Spirit of 
 Salt, and with fixt Alcali it yielded urinous vapours. The matter remaining 
 in the retort was of a reddifh-brown colour. 
 
 An ounce of the powdered Stone, mixed with an equal quantity of fixed 
 alcaline Salt, and urged with a ftrong fire, did not melt ; but formed a quite 
 porous mai’s, in colour inclining to reddifh grey, and weighing two drams lefs 
 than the mixture did at firft. 
 
 CLASS V. Talky Earths and Stones. 
 
 Earths , or foft fiony concretes ; — not acled on by any Add \ \—and fcarce 
 calculable by fire. 
 
 I. VENICE TALC. 
 
 V ENICE Talk is a foft fmooth concrete, undtuous or fopy to the Talc. 
 
 touch, of a whitifh or pale greenifh colour, with a Silver-like luftre, j 
 
 generally found in fmall pieces. It may befplitinto numerous fine plates or Natural Hif= 
 leaves; which, fingly, prove fomewhat flexible and elaftic, and perfectly pel- t0I T 
 lucid, though the entire mafs is commonly opake, or at molt only femitran- 
 
 E 2 fparent. 
 
28 - Earths and Stones. 
 
 Ta l c, parent. The fmalleft pieces are to be preferred ; the larger, however white and 
 apparently pure on the outfide, being apt to havefpecks or veins of heteroge- 
 neous matter in the internal parr. This mineral has received the epithet Ve- 
 netian, not from its being originally the product of Venice, but probably from 
 that city having formerly been a principal mart for it. Though it may per- 
 haps be met with in fome parts of the Venetian dominions, it is more common 
 in other countries ; in Mufcovy, England, Norway, Hungary, Bohemia, 
 Spain, and the Eaftern nations. 
 
 Effeft of fire Talc is generally fuppofed to be entirely unfubd liable by fire. But Mr. 
 
 on in Boyle relates, that having kept fome Venice Talc for a length of time in a 
 giafs-houle furnace, it loft of its volume, its compadtneis, and its luftre, and 
 became more brittle, though it ftill retained the appearance which it had at 
 full'. I have myfelf alf'o obferved a like effedt, the Talc by ilrong calcination 
 having loft its luftre and undluofity, though the diminution in weight was 
 only one drain upon fix ounces : Some white vapours arofe in the calcination, 
 refembling thofe of the Acid of Sea-Salt, but no fpirit could be colledted on 
 repeating the operation in a retort ; the Talc here loft nothing of its weight, 
 but had contradled a blackifh hue. Morhoff, in his epiftle to Langelott on 
 the tranfinutation of metals, declares that he has feenTalc, in the fpace of 
 half an hour and by a fmall fire, calcined into a fpongy mafs, friable betwixt 
 the fingers into a fubtile Powder. Charas has already queftioned this experi- 
 ment, and we may be certain it was not performed on any true Talc: Pro- 
 bably the Lapis Specularis, or Selenites, were miftaken for Talc-, a fufpicion 
 which is countenanced by the author’s own words : He fays the mineral was 
 
 deprived of its yellow colour, a colour which thofe Stones frequently have, but 
 Venice Talc has not. Though Talc however in great meafure refills the 
 adtion of culinary fire, I have found it incapable of refilling the concentrated 
 folar heat : A piece of the true Venice Tale, expofed to the focus of Tfchirn- 
 haus’s large burning lens, prefently melted into an untranfparent vitreous 
 mafs. 
 
 Examined by 1 have examined Talc with all the mineral Acids, and with alcaline Lixivia,. 
 
 Menftrua, which fome report to have a greater adtion on it ; but without finding that 
 either of them had any action at all; the Talc remaining undiminilhed in 
 weight, and neither the Talc or the liquors fuffering any fenfible alteration. I 
 have calcined it alfo with Sulphur, with Sulphur and common Salt, with Nitre, 
 
 ,vah Saxes, with Sal Ammoniac ; without any other effedt than a little change in its colour. 
 
 On trying to melt it with twice its weight of Borax, the Talc fell to the bottom 
 as foon as the Borax came into fufion. Alcaiine Salts, and Cauftic Alcalies 
 taken in four times the weight of the Talc, fucceeded no better; this refrac- 
 tory Earth refufing to unite with them : The Salts being afterwards deliquiated 
 in the air, the addition of Acids occafioned no precipitation, which they mult 
 have done if the Alcalies had taken up in fufion any part of the Talc (e). 
 
 Talc 
 
 (f) Vltref ability of Talk.'] The author- Salts, and too weak a heat. Venice Talc,, 
 leems to have failed in. thefe experiments with half its weight of alcaline Salt, may, in 
 fiom ufmg too large a proportion of the a ftrong fire, be brought into perfedt fufion,. 
 
 though. 
 
E a R t h s and Stones. 29 
 
 Talc is employed, in thole places where it is found in any confiderable Talc, 
 quantity, in compofitions for earthen veftels •, and by lb me for tells and cupels. — -v—w 
 From its fmoothnefs, uncluofity, and brightnefs, it has been greatly celebrated TjieSl 
 as a cofmetic; and the chemifts have fubmitted it to a variety of operations, 
 for procuring from it Oils, Salts, Tin&ures, Magifteries, c 6c for that inten- 
 tion. But all their labours have been in vain; and all the preparations fold 
 under the name of Taic have either contained nothing of that mineral, or only 
 a fine Powder of it. Oleum Tartari per deliquium. Vinegar of Litharge, 
 
 Solution of Sugar, Oil of Almonds, or Oil ot Ben with Sugar of Lead, have 
 been put off under the fpecious name of Oils of Talc. Otto Tachenius pre- 
 tended the Terra foliata Tartari to be an artificial Talc; and accordingly 
 vended, for Oil of Talc, a Solution of that Salt. Dr. Behms Ointment of Taic, 
 which had a large run in Venice, I found to be no other than Pomatum mixed 
 with a little powdered Talc. 
 
 The pulverization of this mineral is attended with fome difficulty. Thep u i ver izat2~ 
 more brittle pieces may be pulverized pretty eafily ; but the very tough and on. 
 flexible fcarce at all ; nor is heating the mortar and peftle red-hot, which fome 
 recommend, of any advantage. The moll commodious method of reducing 
 it into fine Powder is, by cautioufly filing, or grating it with a fifh-fkin. 
 
 II. SOLAR TALC, 
 
 DESIDES the white and the greenifh Talcs treated of in the foregoingS. T a l c„ 
 article, there are yellow, red, and black foliaceous concretes diftinguifhed 
 by the fame name; but thefe are in general rather of the gypfeous than talky 
 kind. Thus the black Talc, mentioned by Hoffmann, which laid on burn- 
 ing coals falls into leaves and acquires a golden colour, feems to be a fpecies 
 of Lapis Specularis. Thole of a yellow colour have been called folar Talcs, 
 and imagined to be impregnated with a fulphur of Gold ; which fome of the 
 chemifts have pretended to extract by Spirit of Salt or Aqua Regis. But the 
 yellow tindure which thefe minerals communicate, and the red fublimate 
 which ariles on diftilling the folutions, proceeds entirely from a ferrugineous 
 matter, common to thele with other coloured Earths. 
 
 though not to perfect tranfparency : With 
 equal its weight, orlefs,of Borax, it runs into 
 a beautiful, pellucid, greenifh yellow Glafs. 
 Talc does not melt with any other Earth, 
 nor even bake or cohere with any but the 
 argillaceous : Mixtures of it with them alt 
 are neverthelefs brought into fufion by a re- 
 markably lefs quantity of faline matter than 
 the ingredients feparately would require. 
 Thus equal parts of Talc and Chalk, with 
 only one fourth their weight of Borax, melt, 
 in no very vehement fire, into a fine tran- 
 fparent, greenifh Glafs, of confiderable 
 
 hardnefs, and great luftre. On fubftituting 
 gypfeous Earths, as the Lapis Specularis, to 
 Chalk, the fufion was as eafy, and the 
 Glafs as beautiful, in colour not green but 
 yellow like the Topaz. Talc with half its 
 weight of Sand, and a quantity of Nitre 
 equal to both, yielded alio a transparent 
 Topaz-yellow Glafs : Several further ex- 
 periments on Talc may be feen in a Memoir 
 by Mr. Pott [Mem. de F Acad, de Berlin , 
 1746,) from which I have here inferred only 
 thofe which I repeated myfelf, and which 
 were all found fully to fucceed. 
 
 III. AML 
 
Earths cmd Stones. 
 
 *> n 
 
 III. AMIANTHUS. 
 
 Amiant. AMIANTHUS and Afbeftus are ffony concretes of the talky kind, 
 ^ though differing from Talc in their external appearance. They are not 
 near fo bright, or fo fmooth and undtuous ; and are compofed not of leaves or 
 plates, but of long filaments like flax ; whence they have been called Earth- 
 flax, Linum JJbeJlinum. They have been fpun into Cloth, and formed into 
 Paper, incombuftible and indeflrudtible in the fire(/). 
 
 P UM ICE. 
 
 IV. P U M I C E. 
 
 H E Pumice is a light very fpongy Stone, rough to the touch, and eafily 
 
 rubbed into Powder. The bed fort is of a white or greyifli colour: Some 
 
 Natural Hif-have a yellowifh, brownifh, or blackifh tinge. Boccone mentions a red Pu- 
 60 *y* mice from Radicofani, but probably miftook fome other Stone for this: I have 
 
 myfelf feen there abundance of reddifh Stones, but no Pumice. The Pumice 
 is found only about Volcano’s, and appears to owe the form in which we meet 
 with it, to flrong calcination by the fubterraneous heat. It is thrown out 
 from the Volcano, along with the fire and lava, in pieces of various figures 
 and magnitudes, fometimes pure, and fometimes intermixed with the other 
 matter. Sometimes it is taken up in the adjacent feas, and hence has been 
 erroneoufly fuppofed by fome to be a marine production ; to be petrified 
 fponge, or the froth of the fea coagulated and indurated with Sand or other 
 fubflances. The whiteA Pumices come from AEtna and Vefuvius : Hecla in 
 Iceland affords more impure forts. 
 
 Examined by Pumice Stone is faid by Ettmuller to be an alcaline abforbent. A part of it 
 Acids. is indeed diffolved or extracted by Acids : 'Out of thirty grains of the pow- 
 dered Stone, Oil of Vitriol diffolved fix grains, Spirit of Vitriol ten. Spirit of 
 
 Nitre 
 
 (/) Incombuftible Paper and Cloth.) There 
 are fome forts of Afbeftos whofe filaments 
 are rigid and brittle ; others more flexible : 
 The firft are not at all to be fpun or formed 
 into Cloth, and the latter very difficultly. 
 This manufacture appears to have been 
 known among the ancients, who according 
 to Pliny wrapt the corps of the dead in 
 afneftine clothes to preferve their afhes fepa- 
 rate from thofe of the funeral pile; an ufe 
 to which they are ftill faid to be applied 
 among the princes of Tartary. The me- 
 thod of preparation, as defcribed by Ciam- 
 pini in the Philofophical Tran factions, 
 N° 273, is as follows. The Stone is laid 
 to foak in warm water, then opened and 
 divided by the hands, that the earthy matter 
 may be wafhed out : This Earth is white 
 like Chalk, and renders the water thick and 
 milky. The ablution being feveral times 
 
 repeated, the flax-like filaments are col- 
 lefled and dried: They aremoft commodi- 
 oufly fpun with an addition of Flax : Two 
 or three filaments of the Afbeftos are eafily 
 twifted along with the Flaxen-thread, if 
 the operator’s fingers are kept oiled : The 
 Cloth alio when woven is beft preferved by 
 Oil from breaking or wafting : On expofure 
 to the fire, the Flax and the Oil burn out, 
 and the Cloth comes out pure and white. 
 Probably from the diffipation of fome ex- 
 traneous matter of this kind proceeded the 
 diminution of weight which an afbeftine 
 napkin fuffered in the fire, in an experiment 
 made before the Royal Society ; for pure 
 Afbeftos lofes nothing. — The fhorter fila- 
 ments which feparate in wafhing the Stone 
 may be made into Paper in the common 
 manner. 
 
Metallic Bodies. 31 
 
 Nitre nine, Spirit of Salt and Aqua Regis each eleven, and diftilied Vinegar Pu m i c e. 
 ten: But all the liquors retained their acidity as ftrong as ii they had taken — v~~— J 
 
 up nothing from the Pumice ; nor did they raife with it any elfervefcence. It 
 is adted on more pov/erfully by Alcalies themielves than by Acids : Fixed 
 
 alcaline Lixivia diffolved fifteen grains out of the thirty j and volatile Spirits 
 twelve grains. 
 
 The Solutions in Acids are all colourlefs ; except that made with the vitrio- 
 lic, which inclines to yellow. The author above-mentioned relates, that dif- 
 tilled Vinegar extracts from Pumice a greenifh tindture ; and hence fufpedts 
 that this Stone is impregnated with Copper. I have never oblerved the 
 flighted: green tindture, but from fuch as had been pulverized in a brafs 
 mortar. 
 
 Sixteen ounces of Pumice, diftilied in a retort, yielded an acid liquor, and By diililla- 
 a vifible empyreumatic Oil, of an extremely ftrong fmell, amounting both tlon * 
 together to half an ounce and one fcruple : In the neck of the retort was found 
 about a fcruple of true Sal Ammoniac, of a brownifh-grey colour. The refi- 
 duum appeared of a blac.dfh grey, and weighed about fifteen ounces. Half 
 an ounce, calcined in a crucible, in an open fire, loft a fcruple, or one 
 twelfth. »i 
 
 The principal ufe of Pumice is in mechanic bufinefifes, for fcouring, cleaning Ufes.. 
 and polifhing metals, Leather, &c. It is fometimes alfo employed in denti- 
 frices. The pumice Powder with which Gold has been polifhed, as retaining 
 fome particles of that metal, is faid by the author of Sol fine vefte to afford a 
 ruby Glafs. 
 
 sect. 11 . . 
 
 METALLIC BODIES. 
 
 M ETALLIC Bodies are divided into Metals , or thofe which are Metals. 
 capable of being worked and confiderably extended under the v— . -w* 
 
 hammer*,, and Semi-metals, or thofe which want that valuable qua- Diihngmfh- 
 lity. There are other charadters alfo, no lefs difcriminative of the two clafies : len, of Me tC? 
 Metals appear when broke of an uniform, or a fibrous, or a granulated tex- andSemi-ms- 
 ture *, whil ft the broken furfaces of Semi- metals (the fluid one, Quick- filver, tals ; 
 excluded) are compofed of large angular plates or flakes : Metals, expofed to 
 
 the moft intenfe degree of culinary fire, if the air is perfectly fhut out, remain 
 fixed and unaltered at the bottom of the veflel ; whilft Semi-metals, impa- 
 tient of vehement heat, arife in fumes into that part of the veflel which is 
 furtheft removed from the fire, and there condenfe again into their original 
 form. 
 
 Though neither Metals or Semi-metals fuffer any effential change from ofperfeA and 
 heat, fo long as the air is excluded*, there are feveral bodies of both cJafles, imperfe.a 
 which by the adtionof fire and air conjointly, are gradually deprived of their ^ etal!lc 
 
 1 metallic 
 
32 Metallic Bodies, 
 
 Metals, metallic appearance and qualities, and converted into a powdery or vitreous 
 ' fubftance., called Calx or Scoria. Hence arifes a further diftribution, into Im- 
 perfect t or thofe which are fufceptible of thefe changes ; and Perfect, or thofe 
 which fuller none. 
 
 CLASS I. Perfect Metals. 
 
 Malle able metals ; — not calcining in the fire , either by themfelves , or with 
 the addition of Nitre, or of Lead, which hafien the deftrudlion or calcina- 
 tion of the imperfedi -,—when corroded by Acids into the appearance of a 
 Calx , recoverable again in their prifline form , without addition , or W//6 
 o;;/y fuch additions as may abforb the Acid. 
 
 I. G O L D. 
 
 G 
 
 OLD. 
 
 lies general 
 properties. 
 
 Ductility, 
 
 gravity. 
 
 Fufibility, 
 
 G OLD (the and Rex metallorum, of the chemifts) is a yellow metal 
 fcarce at all elaftie or fonorous, veryfoft and flexible, the moftdubtile 
 of all metallic bodies. Dr. Halley took one grain of gilt Silver, of which only 
 one forty-eighth part was Gold : This grain was drawn into a wire two ells in 
 length, which examined by a microfcope, appeared every where covered with 
 the Gold : A piece of the wire being put into Aquafortis, the Silver was eaten 
 out, and a tube of Gold remained, which notwithftanding its extreme thin- 
 nel's, was itill opake. 
 
 Gold is of all natural bodies the mod ponderous : Hence it finks in Quick- 
 fllver, whilft all other fubftances [Platina excepted] fwim on the furface. It 
 is upwards of nineteen times heavier than an equal bulk of water : A Paris 
 cubic foot is reckoned to weigh 1368 pounds (a). From its greater denfity it 
 becomes fenfibly hotter than other bodies when laid along with them in hot 
 water. 
 
 Gold melts in a red heat; much looner than Copper or Iron ; though much 
 later than Lead or Tin lb). It is of all metals the mod fixed or permanent in 
 
 the 
 
 (a) Gold — Gravity . J The proportional 
 gravity of Gold to water has been reported 
 to be as 19,640 to 1 : Mr. Browal, in the 
 Swedifh Tranfaddions, makes it no lefs than 
 20. In fundry trials, with different pieces 
 of the fineft Gold I have been able to 
 procure, the. gravity turned out between 
 *9,280, and 19,290. 
 
 (b) Gold — in the fired] Gold requires for 
 s’ts fufion a ftrong red, or a low degree of 
 white heat, a little greater than that in 
 which Silver melts. Whilft fluid, it ap- 
 pears of a bluifh green colour : When 
 grown cold, its furface looks bright, fmooth. 
 
 and confiderably concave. It feems to ex- 
 pand more in the aft of fufion, and to 
 ill rink more in its return to folidity, than 
 any of the other metals ; whence the greater 
 concavity of its furface. Before fufion, it 
 expands the leaft of any except Iron. By 
 Hidden cooling, it becomes, as the other 
 metals, brittle ; an effeft, which has been, 
 in general, erroneoufly attributed to the 
 contafd of fuel during fufion. 
 
 With other Metals.] Gold amalgamates 
 very readily with Mercury, and mingles 
 in fufion with all the metals. It is remark- 
 ably difpofed to unite with Iron ; of which 
 it diffolves many times its own weight, in 
 
 a heat 
 
Metallic Bodies, 33 
 
 the fire: An ounce has been kept for two months together, in a glafs- Gold. 
 houfe furnace, which of all furnaces gives the moft vehement heat, without 
 fuffering the leaft diminution of its weight. Homberg relates, that in the f]XUy ’ 
 focus of Tfchirnhaus’s large burning-glafs, it loft its fixity-, that it imoked, Expofed to a 
 diminifhed in volume, changed into a red Earth, and at laft even vitrified : burning- 
 But as the Gold had been placed on a piece of Charcoal, the vitreous matter S lafs “ 
 probably proceeded from the afhes of the coal. Mr. Geoffroy often affured 
 me, whilft we were making experiments together with the fame burning lens, 
 that no fuch vitrification had been obferved, when any thing befides Charcoal 
 was ufed for the fupport. 
 
 Gold diffolves in a mixture of the nitrous and marine Acids, called, from its Solution, 
 adlion on this Rex Metallorum, Aqua Regia : Either of thofe Acids fingly have 
 no effedt upon it; nor is it adted on by the the vitriolic. Boerhaave fays that 
 Sea-Salt or Sal Gem are the only menftrua of Gold ; and that both thefe Salts 
 diftolve it, whether applied in the form of a Lixivium or Spirit : Experience 
 affords no foundation for this affertion (c). The folution in Aqua Regis is of 
 
 a Gold 
 
 a heat not much greater than that in which 
 Gold by itfelf melts : The mixture is of a 
 filver colour, very brittle, and hard. All 
 the metals, except Copper, debafe the colour 
 of Gold ; and if their quantity is nearly 
 equal to that of the Gold, almoft entirely 
 conceal it. All but Copper and Silver de- 
 ftroy its malleability ; none fo remarkably 
 as Tin and Lead : A moft minute portion, 
 even the vapour, of thefe renders Gold ex- 
 tremely brittle; though a ffnall proportion 
 of Gold forms with them compounds fuffi- 
 ciently dudtile, more fo than either the 
 Lead or Tin by themfelves. 
 
 (c) Solubility in Acids. ~\ Gold is commonly 
 fuppofed incapable of being diffolved in any 
 fimple Acid. It appears however- to be fo- 
 luble, in certain circumftances, both by the 
 nitrous and marine, though not fo readily 
 or plentifully as by a mixture of them. 
 
 Dr. Brandt produced before the Swedifh 
 academy of fciences a folution of it in the 
 nitrous Acid, obtained in parting, by that 
 Acid, a mixture of Gold and Silver. The 
 mixed metal was boiled with Aquafortis in 
 a glafs body fitted with a head and receiver, 
 the liquor poured off, and the codlion re- 
 peated with frefh parcels of ftronger and 
 ftronger nitrous fpirits, till all the Silver was 
 judged to be extracted : The laft parcel was 
 boiled down till the matter at the bottom 
 looked like a dry Salt; on boiling this in 
 frefh Aqua fortis, in clofe veflels as before, 
 
 a part of the Gold was diffolved, and the 
 liquor tinged yellow. See the Swedifh 
 TranfadLions for the year 1748. But though 
 Gold is by this means truly diffoluble in the 
 nitrous Acid, the union betwixt them is ex- 
 tremely flight; the Gold being not -only 
 precipitated on the addition of Silver, or 
 fuch other metals as diffolve in that Acid, 
 but likewife fubfiding fpontaneoufly upon 
 expofure to the air. 
 
 The marine Acid has no adt ion on Gold 
 in its metallic ftate, in whatever manner the 
 Acid be applied : But if the metal is previ- 
 oufly attenuated, or reduced into the form 
 of a Calx, either by precipitation from 
 other Menftrua, or by calcination in mix- 
 ture with calcinable metals, this Acid will 
 then perfedfly diffolve, and keep it perma- 
 nently fufpended. Gold precipitated from 
 Aqua Regis by fixed Alcalies, and edulco- 
 rated by ablutions with boiling water, I 
 have diffolved even in a very weak Spirit of 
 Salt by moderate digeftion. This folution 
 appears of the fame yellow colour, as that 
 made in Aqua Regis : It gives the fame 
 purple ftainto thefkin, feathers, bones, and 
 other folid parts of animals ; the fame 
 Violet {Lain to Marble ; and ftrikes the 
 fame red colour with T in, Even when 
 common Aqua Regia is made ufe of for 
 the menftruum, it feems to be chiefly by 
 the marine Acid in that compound liquor, 
 that the Gold is held in folution : In diftil- 
 lation, it is the nitrous Acid which arifes 
 F and 
 
34 
 
 Gold. 
 
 changes of its 
 properties by 
 krti 
 
 whether de- 
 ftrufUble or 
 producible. 
 
 Metallic Bodies. 
 
 a Gold yellow colour, and ftains the fkin, where-ever it touches, of a fine 
 purpliih red, which is noteafilygot off! 
 
 Singular and unalterable as the properties of Gold appear to be, they are 
 eafily mattered by chemiftry. A fingle grain of Tin will deftroy the dutftilitv 
 of a thouland grains of Gold ; rendering the mo ft malleable Gold not only 
 incapable of being extended, but of bearing the hammer at all. In Kunckel’s 
 Laboratorium Chymicum , there are proceffes by which Gold may be fublimed and 
 diftilled over the helm ; and furely what lublirncs or diftils has loft its fixity. 
 Mercury- fublimate and Sal Ammoniac volatilize it [d). There is a certain 
 common and well known fubjecl, plentifully made ufe of by every body, 
 which robs Gold of its luftre, its colour, and its malleability, and renders it 
 white and brittle: But this fubftance, as it might give rife to abufes, I forbear 
 to name. Gold melted repeatedly with Borax, becomes paler and paler on 
 every fufion ; and there are fundry other fubftances, as Butter of Antimony, 
 Zinc, and the fmoking Spirit of Tin, from which it fuffers notable alterations. 
 After all thefe changes however, it is ftill reducible to its original ftate : The 
 brittle, the white, the fublimed, the diftilled Gold, may all be reftored to the 
 purity and properties of the Gold at firft. The chemifts have long laboured 
 in the deftrudion of this metal, and allow it to be eafier to make Gold than 
 to deftroy it; though it does not appear, that either of thefe problems is 
 entirely beyond the reach of art: For a little Gold has in divers experiments 
 been produced; and Gold was deftroyed in the prefence of Mr. Boyle OF 
 
 Aqua 
 
 and the marine which remains combined with 
 the Gold into a blood-red mafs, foluble, 
 like the combinations of moft metallic bo- 
 dies with that Acid, in Spirit of Wine. 
 
 (d) Volatilization cf Gold.] The volatiliza- 
 tion of Gold, though it has been looked 
 upon as one of the proceffes of the fublimer 
 metallurgy, may be effe&ed without diffi- 
 culty. If a folution of Gold in common 
 Aqua Regia be infpiffated, the refiduum. 
 diffolved in. frefh Aqua Regis, and the 
 liquor diftilled off : Upon haftily increafing 
 the fire towards the end of the operation, 
 part of the Gold diftils in form of a high 
 Saffron- coloured liquor, and part fublimes 
 into the neck of the retort, in clufters of 
 long /lender Cryftajs, of a deep red colour, 
 fufible in a frnall heat, eafily foluble in 
 water, and deliquiating in the air. By re- 
 petitions of the procefs, the whole quantity 
 of the Gold may thus be elevated, except- 
 ing a fmall" proportion of white Powder, 
 whofe nature and qualities may deferve fur- 
 ther examination. 
 
 (e) Boyle’s degradation of Gold.'] The expe- 
 riment, here referred to, ; is a very curious 
 
 and extraordinary one, though it falls fhort 
 of proving the deftru&ibility of Gold. A- 
 bout one eighth part of a grain of a Powder 
 communicated by a ftranger, was projedted, 
 upon two drams of fine Gold in fufion, and 
 the matter kept melted about a quarter of 
 an hour. During the fufion, the metah 
 looked like ordinary Gold : When cold, it 
 appeared of a dirty colour, and as it were 
 overcaft with a thin coat almoft like half 
 vitrified litharge : The bottom of the cru- 
 cible was ovenaid with a vitrified fubftance, 
 partly yellow, and partly reddifh brown 
 with a few fmall globules, more like impure. 
 Silver than Gold. The metal was brittle, 
 internally like Brafs or Bell-metal, on the 
 touchftone more like Silver than Gold : Its 
 fpecific gravity was to that of water only as 
 1.5 y to 1. There was no lofs of weight. 
 
 Though the Gold was furprizingly al- 
 tered in this experiment, it was not de- 
 ftroyed : Mr. Boyle himfelf informs us, 
 
 that fixty grains of the mafs yieided on cu- 
 pel lation fifty-three grains of pure Gold; 
 with feven grains of a fixed, ponderous, 
 dark coloured fubftance : And probably 
 
 this laft, by proper treatment, might like- 
 wife have been reduced into Gold again. 
 
Metallic Bodies. 
 
 35 
 
 Aqua Regia, the proper menftruum of Gold, is commonly prepared by Gold. 
 diffolving one part of Sal Ammoniac in four of Aqua fords or Spirit of Nitre, *-— ■ v —*— ■> 
 Kunckel diredts a commodious method of obtaining the exadl proportions 
 neceffary for the folution : The Gold, either in form of leaves, or granulated, diffolvin" it, 
 or flatted into thin plates, then made red-hot and cut in fmall pieces, is to be 
 put into a fuitable quantity of Aqua fortis, a gentle heat applied, and fome 
 powdered Sal Ammoniac added gradually, by little and little at a time, till 
 the whole of the Gold is difiolved (/). 
 
 There are, befldes this, fome uncommon and curious folutions of Gold, foluble by 
 as the fulphureous one, which was difcovered by Stahl, and publifhed in SuJ P llur ’ 
 his tradl de vitulo aureo (g). Langelot contrived a machine, which he calls infipid Men- 
 the philofophic mill ; in which Leaf-gold was ground with water to fuch a^ua for 
 degree of tenuity, as to pafs along with the water through the pores of a^ o!d ’ 
 filter: This however is no true folution, the Gold being here barely divided 
 into minute atoms, which on (landing fubfide again from the water by their 
 own gravity. When Gold is triturated for a length of time in a glafs- mortar, 
 a little vitrefcible matter is obtained : This does not proceed, as fome have fup- 
 pofed, from the Gold, but from a portion of the matter of the Glafs rubbed 
 off in the grinding. 
 
 Much has been talked of infipid menftrua for Gold. Hoffman looks upon 
 all thefe, as matter of ficlion, or of fraud ; and queftions the exiftence of any 
 fubjedt in nature, from which fuch a menftruum could be prepared. Thus 
 much however is certain, that if Gold be put into a receiver with fome plain 
 water; and a Glafs body, containing a certain liquor, be fitted with ahead 
 joined to the receiver; and the whole fuffered to (land in the cold, the Gold will Reputed 
 by degrees, imperceptibly difiolve in the water. Kunckel relates, that Gold Menifrua. 
 
 may 
 
 (f) Kunckel' s method of diffolving Goldd] By 
 this method, a much fmaller quantity of the 
 menftruum proves fufficient, than if the Sal 
 Ammoniac was previoufly diftolved in the 
 Aqua fortis ; the conflict, which each addi- 
 tion of the Salt raifes with the Acid, greatly 
 promoting the diflolution. of the Gold. 
 Aqua fortis of moderate ftrength will thus 
 take up about one third its weight of Gold ; 
 whereas an Aqua Regis, ready prepared 
 from the fame Aquafortis, will not diifolve 
 above one fifth its weight. Sea-Salt, ma- 
 naged in the fame manner, anfwers better 
 than SaJ Ammoniac. 
 
 (g) Stahl's fulphureous folution of Gold. ] 
 Gold is not adted upon in the leaft by pure 
 Sulphur; which fcorifies or diftolves in fu- 
 fion every other metallic body except Zinc 
 and Platina. But if the Sulphur be previ- 
 oufly melted with an equal quantity of fixed 
 alcaline Salt ; this compound, melted with 
 Gold, readily unites with it into an uniform 
 
 mafs, which diftolves in water without any 
 feparation of the Gold. The author above 
 mentioned endeavours to prove, that ful- 
 phurated Alcali was the medium by which 
 Mofes calcined the golden calf fo as to be 
 mifcible with water. The folution, beftdes 
 a naufeous tafte from the Sulphur, has a 
 peculiar penetrating bitternefs, not difco- 
 verable in any other metallic folution made 
 by the fame means. 
 
 Though the compofitions of Sulphur and 
 Alcali feem to unite more intimately with 
 Gold than with other metals, their affinity 
 with it is but flight: Copper or Iron, added 
 to the matter in fufion, difunite and preci- 
 pitate the Gold. The Gold, thus reco- 
 vered, and purified by the common pre- 
 cedes, proves remarkably paler coloured 
 than at firft. In an experiment related by 
 Dr. Brandt in the Swedifh Memoirs, the 
 purified Gold turned out nearly as pale as 
 Silver, without anv diminution of its weight. 
 
 F 2 
 
3 6 
 
 Metallic Bodies. 
 
 Gold, may be diflolved by placing it in a receiver with Spirit of Wine, and driving 
 u— v ^ over Spirit of Nitre upon it-, or by putting the Gold into Spirit of Salt, and 
 adding fome drops of Spirit of Urine. Neither of thefe experiments fucceeded 
 with me; though Kunckel rarely advances anything as fa£t, that is not 
 really fo(A). 
 
 Aurum Ful- From the folution of Gold in Aqua Regis is prepared the clay-like Preci- 
 Kitnans. pitate, called from its explofive power Aurum Fulminans. The folution is di- 
 luted with water ; and either a fixt alcaline Lixivium, or a volatile alcaline Spi- 
 rit, gradually added, or the fixt and volatile Alcali dropt in alternately, till 
 the precipitation is completed. The Precipitate obtained by volatile Alcalies 
 is in lei’s quantity than by the fixed, but fulminates more frrongly (/). This 
 preparation is to be dried with the utmoft caution : It explodes from being 
 
 barely let in a warm place, or moderately rubbed in a mortar, and its explofion 
 is extremely violent, fo as to have been too often productive of terrible effects ; 
 of which examples may be feen in the Ephemerid.es nature curioforum , and in 
 theBrefiau Collections. It is commonly fuppofed to exert its aCtion only 
 downwards : But it aCts equally in all directions, though its effeCt is molt con- 
 fpicuous on the folid body upon which it is placed. The report is preceded 
 by a flafh, vifible in the dark ; and during the explofion, the Gold is revived 
 into little granules, which may be caught by means of proper vefiels, as I 
 fhewed to ieveral members of the Royal Society in London, and as Kunckel 
 eaufe of its alfo has oblerved. The fulmination appears to proceed, not from the Gold, 
 lamination, but from a fubtile ammoniacal Nitre, or Nitrum jlammans , compofed of the 
 nitrous Acid and volatile Alcali : A Precipitate made without volatile Alcali, 
 either in the menftruum or precipitant, will not fulminate : If to fuch as does 
 fulminate we add vitriolic Acid, which abforbs the volatile Alcali from the 
 nitrous, its fulminating quality will be deftroyed: Saturated afrefii with vola- 
 tile Alcali, it recovers its explofive power. ThatGold is not neceffary to the 
 fulmination, appears from the effeCl ol the pulvis fulminans and other fulminat- 
 ing preparations in which there is no Gold. 
 
 Some 
 
 (h) Reputed Menjlrua for Gold.'] I have 
 Mkewife tried thefe liquors, and the mix- 
 tures of vitriolic Acid with Salt of Tartar 
 and with urinous Spirits, fatd by the fame 
 author to be menftrua for Gold ; without 
 fuccefs. Mr. Pott informs us, in a paper 
 m the Berlin Memoirs for the y.ear 1752, 
 that he obtained a fpirit which diffolved 
 Gold, by diftilling a folution of the fecret 
 Sal Ammoniac (that is, a neutral Salt com- 
 pofed of volatile Alcali and Oil of Vitriol) 
 made in twice or thrice its quantity of 
 Aqua fortis. 
 
 (/) Precipitation of Gold by Alcalies,] When 
 fixed Alcalies are made ufe of, the Precipi- 
 tate weighs about one fourth more than the 
 Gold: employed. With volatile Alcalies 
 
 alfo, if they are cautioufly added in no 
 larger proportion than is fufficient to fatu- 
 rate the Acid, the quantity of Precipitate 
 proves nearly the fame : But if the volatile 
 Spirit is added in an over-proportion, it re- 
 difTolves a part of the Gold which it had 
 before precipitated, and the liquor becomes 
 again confiderably yellow. I could not, 
 however, by any addition of the fpirit, 
 procure a total rediffolution of the Gold, 
 though both the animal oily Spirits, and 
 that of Sal Ammoniac, prepared both with 
 Salt of Tartar and with Quick-lime, were 
 made trial of: Nor did either-of thefe fpi- 
 rits fenfibly diffolve, or extract any'tinge 
 from precipitates of Gold which had been 
 thoroughly edulcorated with boiling water. 
 
Metallic Bodies, 37 
 
 Some prepare their Aurum Fulminans [of a purple colour] by evaporating Gold. 
 
 the i'olutionof Gold to drynefs, diffolving the dry matter in freffi Aqua Regia, 
 
 infpiffating the liquor again, and repeating this procedure a fecond and a third 
 time: The folution is at laft evaporated to the confidence of Oil, and then 
 precipitated with Oil of Tartar per deliquium. This method is not to be 
 approved ; as we can feldom, from fuch thick liquors, obtain a complete 
 precipitation. 
 
 Solution of Gold may be precipitated by fundry fubdances befides Alcalies ; Precipitations 
 as Quick-filver, folution of Quick-filver, folution of Vitriol, iolution of Gold. 
 Verdigris, Tin, i kV. ( k ) — Solution of Tin, dropt into a Iolution of Gold largely Ruby Glafs, 
 diluted with water, or Tin itfelf added to the diluted liquor, changes its yel- 
 low colour to a fine purplifh red (/). By this mark, minute portions of Gold 
 
 may be difcovered in liquors. The Precipitate, which fubfides on handing, 
 is likewife of a purplifh red; and, melted with a large proportion of frit t or 
 colourlefs Glafs, tinges it of a beautiful red colour: Kunckel obferves, that 
 
 one part of Gold is fufficient to communicate a ruby red to twelve hundred 
 and eighty parts of Glafs, and a fenfible rednels to nineteen hundred and 
 twenty (m). If folution of Gold made in Aqua Regis be evaporated a little, Cry ftals of! 
 
 fome rectified Spirt of Wine added, and the whole differed to remain, quiet, the Gold. 
 
 Gold will lhoot into Crydals. 
 
 Gold 
 
 {k) Precipitation of Gold by metallic fubflances.] 
 All the metallic bodies which diflol ve in 
 Ao t ua Regia, Platina excepted, precipitate 
 Gold from it. Mercury and Copper throw 
 down the Gold in its blight metallic form ; 
 the others, in that of a Calx or Powder 
 which has no metallic afpeft. 
 
 Iron combined with the vitriolic Acid, 
 that is Vitriol, of Iron, though it continues a 
 precipitant for Gold, precipitates no metal- 
 lic body befides ; and hence we are fur- 
 nifhed with a commodious method of puri- 
 fying Gold from admixtures of all other 
 metals. Kunckel directs Vitriol of Copper 
 for this purpofe, having probably made the 
 experiment with a mixed Vitriol partici- 
 pating both of Copper and Iron, and attri- 
 buted to one ingredient what was effected 
 by the other : No Vitriol but that of Iron 
 makes any precipitation in folution of 
 Gold. 
 
 (/) Purple- or red with Tin, ] This phoeno- 
 menon fucceeds with certainty when Tin 
 in fubftance is ufed, provided the folution 
 of Gold be largely diluted with water 
 With folution of Tin we cannot fo eafily 
 fecure fuccefs, either in regard to the co- 
 lour or precipitation — It is obfervable, that 
 
 though the Gold is here precipitated by 
 Tin from the diluted folution ; yet if the 
 whole be fuffered to Hand till the water has 
 in great meafure exhaled, the Gold is taken* 
 up afrefh, the liquor becomes yellow as at 
 firft, and only a white Calx of Tin re- 
 mains. 
 
 (m) Ruby Glafs.] The art of tinging, 
 Glafs throughout of a ruby colour was dif- 
 covered fince the middle of the laft century 
 by Dr. Caffius : The red glaffes of earlier 
 date are only fuperficially painted. Kunc- 
 kel was the firft who brought the procefs< 
 to any confiderable perfection ; and, as he 
 informs us himfelf, prepared the Glafs in. 
 large quantity, and vended it at a great 
 price: He fays he made a chalice of it for 
 the elector of Cologn, of an uniform fine 
 colour throughout, weighing no lei's- than, 
 twenty-four pounds. 
 
 All that we can colled: from his writings,, 
 relating to the procefs, is, that he ufed for 
 the , tinging ingredient the Precipitate of 
 Gold made with Tin ; that this colours z 
 large quantity of Glafs,, as above men- 
 tioned ; that the procefs does not conftantly 
 fucceed ; that oftentimes the Glafs comes 
 out of the pot colourlefs as Cryftal, and re- 
 
 oeiyess 
 
3 8 
 
 Metallic Bodi 
 
 E S. 
 
 Gold. 
 
 Of Gold as 
 medicine. 
 
 Gold has been imagined to be poffefled of extraordinary medicinal virtues ; 
 and many preparations, dignified with the name of this precious metal, have 
 a been impofed upon the public. But the virtues aferibed to Gold have 
 apparently no other foundation than credulity and luperftition ; and moft of 
 the golden medicines have no Gold in them : Even when Gold has been em- 
 ployed in the preparation, there is feldom any of it retained in the product. 
 We may fay with Ludovici, “ It is better to make Gold out of medicines, 
 “ than medicines out of Gold.’ 5 
 
 Of extrafling Some have pretended to extract the tinging matter of Gold, fo as to leave 
 its tinging t [ ie body 0 f (he metal white ; milled either by employing a menftruum, which 
 of itfelf acquired a colour during the digeftion *, or by finding at the bottom 
 >of the Glafs, or on the furface of the Gold, a little white matter, which was no 
 other than Silver previoufiy contained in the Gold, or Regulus of Antimony 
 with which the menftruum had been impregnated : It was by ufing fuch a 
 menftruum (the bezoardic Spirit of Nitre, as it is called) that Mr. Boyle was 
 deceived (»). 
 
 Hoffman, 
 
 matter. 
 
 ceives its rednefs on being expofed to a 
 fmoky flame ; that Nitre or Sal Ammoniac, 
 added to it in fufion, call forth its latent 
 colour ; and that the colour thus extricated 
 by the latter is the moft beautiful, but 
 quickly difappears again upon continuing 
 the fire. From the experiments ofOrfchal, 
 in a treatife entitled Sol fine vefie , it appears, 
 •that other preparations of Gold, even the 
 muddy matter obtained in polifhing Gold 
 with Pumice, anfwer equally with the Pre- 
 cipitate by Tin. 
 
 One Grummet, who had been an opera- 
 tor to Kunckel, publifhed a tradl in oppofi- 
 tion to the foregoing, under the title of Sol 
 non film ve/le ; in which he endeavours to 
 prove, by experiments, that the Gold has 
 no fliare in the production of the colour, 
 and that this proceeds wholly from Man- 
 ganefe employed in the compofition of the 
 glafs. He affirms, that if white or Venice 
 Glafs (in the making of which, a proportion 
 of Manganefe is ufed, for promoting the 
 tranfparency,) be reduced into powder, and 
 melted with one fourth or one eighth of 
 Nitre, it will acquire the true ruby colour ; 
 and that no addition of Nitre or of Gold 
 will communicate any thing of that colour 
 to a Glafs made from Alcali and Flint with- 
 out Magnanefe. 
 
 Thus much is certain, that Glafs maybe 
 tinged of a fine red colour by means of 
 Manganefe; that this colour totally difap- 
 pears upon a continuance of the fufion ; and 
 
 may be again brought back by an addition 
 of Nitre. 
 
 In regard to Gold, with its calx precipi- 
 tated by Tin I have, in the glafs-houfe fur- 
 nace, tinged common white Glafs of a true 
 ruby red. With fritts compofed of calcined 
 Flint and alcaline Salt or Borax, melted 
 with the fame calx in a wind furnace, the 
 colour did not equally fucceed, though the 
 procefs was upwards of twenty times re- 
 peated and varied ; and Sal Ammoniac, 
 Nitre, and fmoky flames, were called in 
 aid : The Glafs proved commonly yel- 
 Jowiflh, with violet-coloured veins : Some- 
 
 times there were ruby-coloured fpecks, and 
 generally a button of revived Gold at the 
 bottom. 
 
 («) Boyle's white metal from Gold.'] Mr. 
 Boyle relates, that on diffolving'fine Gold 
 in an Aqua regia diftilled from Butter 
 of Antimony and Aqua fbrtis, a confider- 
 able quantity of white powder remained 
 undillolved : That the Gold, being re- 
 duced into a body, yielded on a fecond 
 folution more of this powder, but in lefs 
 quantity than the firft >time : That with 
 common good Aqua regia, he could ob- 
 tain, from the very beft Gold, fome little 
 quantity of the like white powder : And 
 that thefe powders, melted with Borax, gave 
 a white malleable metal, whole appearance, 
 folubility in Aqua fortis, and odious bitter- 
 nefs when diflolved, (hewed to be true Silver. 
 
 We 
 
Metallic Bodies. 39 
 
 Hoffman, the elder Geoffroy and others, prepare tinctures of Gold by Spirit Gold. 
 of Wine and eflential Oils, from a folution of the metal made in Aqua Regis : J— — •v'— ■ 
 Some take the Oleum vini , or a well made Spiritus vitrioii dulcis : But all thefe Ill)< - lure5, 
 preparations receive their virtues from the additional matters, and not from the 
 Gold. It is obfervable, however, that Oil of Juniper-berries, and perhaps Gold taken up 
 other eflential Oils, mixed with a folution of Gold in Aqua Regis, take up the from Aqua 
 Gold from the Acid, and acquire commonly a blackifh colour on the upper Re S ls by Oils, 
 furface, and a Gold-yellow one underneath (o) : If this mixture is fet to digsff, 
 we muft be cautious in regard to the fire, for it is apt to grow fuddenly hot, 
 and at once run over the veflel. Hoffman fays, howjuftly I pretend not to 
 determine, that the belt preparation of Gold for medicinal ufe, is a mixture 
 of two parts of martial Regulus of Antimony and one of Gold melted toge- 
 ther, and calcined in a glafs phial till they are changed into a purple crocus. 
 
 The largeft quantities of Gold are met with in the Spanifn Weft Indies : Natural hif- 
 There are mines of it alfo in fome parts of Europe, particulary in Hungary tory of Gold, 
 and Tranfylvania. It is either imbedded in flinty or other ftones, or inter- 
 mingled among the loole earth *, always in its metallic form, though the par- 
 ticles are commonly very fmall and often indiftinguifhable (/>)• It is never 
 found in the ftate of a true ore, unlefs when blended with a large proportion 
 
 of 
 
 We cannot fuppofe, as fome have done, 
 that this metal proceeded from an antimo- 
 nial Regulus contained in the menftruum ; 
 any more than, with Mr. Boyle, that it was 
 a part of the Gold adlually tranfmuted into 
 Silver. It is by quartation with Silver (fee 
 page 43 ) that Gold is commonly refined ; 
 and in that procefs it always retains a por- 
 tion of the Silver, feparable by Aqua Regia. 
 When Aqua Regia is made with an under 
 proportion of marine Acid, it diffolves a 
 litcle Silver along with Gold ; and hence 
 probably the Silver obtained on the fecond 
 diffolution. 
 
 ( 0 ) Gold taken up from Aqua Regia by effential 
 Oils , ] The Gold, thus imbibed by Oils, 
 does not long remain difl'olved in them ; in 
 a few hours it feparates, in bright yellow 
 films, to the fides of the Glafs — The fubtile 
 oily fluid called Aether or aethereal' Spirit of 
 Wine, takes up the Gold more readily and 
 perfectly than the common Oils, and keeps 
 it permanently difl'olved, the acid liquor un- 
 derneath appearing colour’efs : The yellow 
 aethereal folution, carefully poured off, and 
 kept for fome time in a glafs ftopt with 
 cork fo as that the fpirit may flowlv exhale, 
 yields long, prifmatic, tranlparent Cryftals, 
 1 -- 
 
 in fhape like thofe of Nitre, in colour yel- 
 low like Topaz Rectified Spirit of 
 
 Wine mingles uniformly with the iolution 
 of Gold made in acids : If the mixture is 
 Offered to ftand for fome days in a gla(s 
 Rightly covered, the Gold is by degrees re- 
 vived, and arifes in bright pellicles to the 
 furface — Groffer inflammable matters,Wine, 
 Vinegar, Solutions of Tartar, throw down 
 the Gold, in its metallic form, to the bot- 
 tom Gold is the only metallic body 
 
 which is thus feparable from its folutions in 
 Acids by either of thefe fubftances : And 
 hence Gold may by thefe means be purified 
 from all admixtures, and fmall proportions 
 of it in liquors readily difcovered. 
 
 (p) Gold in Stones , Ores , &c.] There are 
 two general methods of extrabling Gold 
 from its ore or matrix ; amalgamation and 
 fufion. 
 
 1. When the Gold is fuperficially em- 
 bedded in earths or Hones, in its metallic 
 form; the mineral is reduced into powder,, 
 the lighter earthy parts feparated by ablu- 
 tion With water, and the remainder tritu- 
 rated with a quantity of Quickfilver j. 
 which imbibes or amalgamates with the 
 Gold,, whillt the earthy and ftony matters' 
 
4<s Metallic Bodies. 
 
 Gold, of other metals : The Gold Ore of Rammelfberg in Godar holds only a few 
 grains on an hundred weight. Some Gold is alio met with in fundry rivers, 
 as the Tagus, the Ganges, the Rhine, the Saale, the Niger, the Danube, and 
 many others, commonly in fine dull, often in fiat molecules, fometimes fu- 
 fpended by the water in invifible atoms, which fettle upon {landing, and are 
 diftinguifhed by the name of river or wafhGold: Thefe golden particles 
 
 doubtlefs 
 
 float on the furface and are eafily wafhed 
 off : The wafhed Amalgam being commit- 
 ted to diftillation, the Mercury arifes, and 
 the Gold is left behind. This is the me- 
 thod by which Gold and Silver are extrafted 
 from their ores in the Spanifh Weft- 
 Indies. 
 
 2. When the Gold is too intimately com- 
 bined in the compofition of the ore, to be 
 feparable by Quickfilver ; the mineral is 
 brought into fufion by fire. If the quantity 
 of Gold was very confideiable, it would fub- 
 fide from the fluid matter by its own gra- 
 vity, by whatever means the fufion was 
 procured : But in ores, the Gold is in too 
 fmall proportion, its particles too minute 
 and too widely diffufed, to fepaiate in this 
 manner, without the addition of fome other 
 metallic body to imbibe and collect it. 
 The addition commonly made ufe of is 
 Lead ; this metal eafily vitrifying in the fire; 
 and, when vitrified, powerfully promoting 
 the vitrification or fufion of earthy or ftony 
 matters; at the fame time that the part 
 which remains unvitrified imbibes the Gold 
 and carries it to the bottom. Bifmuth an- 
 fwers the fame end, rather more effectually; 
 its Glafs being fomewhat more active as a 
 flux than that of Lead, in regard both to 
 the facility and tenuity of the fufion. The 
 Gold thus transferred into Lead or Bifmuth 
 is feparated by keeping the mixture in fufion 
 upon a cupel or teft : The cupel is a fmall 
 
 fhallow vefl'el made of bone-afh, which ab- 
 forbs the Lead or Bifmuth in proportion as 
 they vitrify : The teft is a large oval hearth, 
 ■on which the Lead, as it vitrifies and arifes 
 to the furface, is raked off from the Gold, 
 ©r blown off by bellows. 
 
 Minerals containing Gold intimately 
 blended in their compofition are frequent 
 in raoft parts of the world. Many of our 
 .common fands are perhaps richer in this 
 metal than the ores of Peru; though they 
 yield it with fuch difficulty, that it is fcarce 
 to be extracted from them to any advan- 
 
 tage. The yellow, red, black, ferrugine- 
 ous fands are the richeft, but at the fame 
 time the moft refraftory ; the matter being 
 not only very hard of fufion, but the Gold 
 ftrongly retained, and defended from the 
 a&ion of Lead, by the ferrugineous part. 
 Becher formed great expectations from fome 
 experiments on the more fufible Sands ; 
 which, though they hold lefs Gold, yield it 
 with more eale. 
 
 Mr. Hellot informs us, (in his French 
 verfion of Schluter) that in eleven effays of 
 the fame ferrugineous fand, made by Mr. 
 Lebsrecht, the proportion of noble metal 
 turned out conftantly from eight hundred 
 and forty to eight hundred and forty-four 
 grains on the quintal or hundred pounds ; 
 and that from one fourth to one third of 
 this was Gold, and the reft Silver. He 
 obferves that different parcels of fand, taken 
 up at no great diftance from one another, 
 differ in degree of richnefs ; fome having 
 yielded above a thoufand grains on the quin- 
 tal, others only three hundred and fifty, and 
 others again containing nothing but Iron. 
 Thefe effays were made, by mixing the 
 fand (previoufly four times calcined, and as 
 often quenched, whilft red-hot, in water) 
 with twice its weight of granulated Lead, 
 and equal its weight of black flux, fpreading 
 fome common fait on the furface, and 
 melting them, with a fire ftrongly excited 
 in a blaft-furnace, till the fcorise flowed 
 thin as water, fo as not to adhere to the 
 iron-rod with which the matter was from 
 time to time ftirred. 
 
 The precious metal may be extracted 
 alfo, and perhaps more perfectly, by vitrify- 
 ing the fand with Glafs of Lead, and after- 
 wards reviving the Lead. Sulphur, added 
 to the vitreous compound, readily unites, 
 and changes it into a fparkling mafs, of a 
 femimetallic afpeCf, fimilar in quality to 
 the natural Lead Ores which participate of 
 Gold and Silver, and yielding its metallic 
 contents by the fame treatment- 
 
Metallic Bodies. 41 
 
 doubtlefs proceed from fome mines or veins of Gold ; from which the metal Gold. 
 has been waflied out, and carried down by the ftream. Some have pretended L— <v— 
 to find perfebt Gold in vegetables, particularly in the vine-tree ; but on exa- 
 mining thofe Gold-like fpecks or granules, by fire, by Quickfilver, or other 
 trials, they foon dilcover themfelves to be no Gold. 
 
 Gold coins and utenfils are not made of pure Gold, but have always an Its alloy,- 
 alloy of Silver, or Copper, or both together, by which the Gold is rendered 
 firmer, harder, and more fonorous (q). When Gold is perfebtly pure, it is 
 called Gold of twenty-four carats ; the meaning of which is, that in an ounce of 
 the metal all the twenty-four fcruples are pure Gold. If only twenty-three 
 lcruples are fine Gold, and the other fcruple a bafer metal, it is called Gold 
 of twenty-three carats \ and in general, the number of carats by which the fine- 
 nefs is exprefied, denotes the number of fcruples of fine Gold in an ounce or 
 twenty-four fcruples of the mixt. The ancients fuppofed the Gold of different 
 countries to differ in quality ; the Armenian to be the belt, the Hungarian 
 next to it, and the Rhenifli the worft. But Gold, when perfedtly pure, is 
 always one and the fame, where-ever it is to be found; no other differences 
 being obferved in it than what proceed from an admixture of fome other metal. 
 
 There are different methods of feparating Gold from admixtures of other 
 metals. If only a bafe metal is mixed with Gold, they may be feparated by purification 
 telling or cupellation with Lead ; the bafe metal vitrifying with the Lead, from the baf<? 
 whilft the Gold remains unhurt (r). metals 
 
 Silver, which refills the dellrudlive power of Lead equally with Gold it- 
 felf, is feparated by acid menftrua. For this purpofe, we mull firft examine, 
 whether the mixture contains mcll Gold, or moil Silver : If the Gold is found Method of 
 to prevail, the metal is to be flatted into plates, or granulated, and put into aparting Gold 
 proportionable quantity of Aqua regis, which diffolves the Gold, and leaves antl Sllver * 
 the Silver in the form of powder at the bottom : The Silver, walhed and 
 dried, may be melted into a mafs, with the addition of a little Tallow, and 
 fome Nitre or Borax ; and the Gold may be recovered from the liquor by pre- 
 cipitation 
 
 (q) Alloy .] Standard Gold contains one 
 twelfth its weight of alloy, moft commonly 
 of Copper ; this metal not weakening the 
 colour as Silver does, but rather heighten- 
 ing it : It is fuppofed alfo, perhaps on no 
 very good foundation, that Copper preferves 
 the malleability of Gold in certain circum- 
 ftances wherein pure Gold would become 
 brittle. The fpecific gravity of this com- 
 pound is lefs than the mean gravity of the 
 Gold and Copper unmixed. 
 
 (r) Cupellation with Lead .] Gold is not fo 
 perfedtly purified by this procefsas has been 
 commonly fuppofed. It almoft always re- 
 tains a portion of the Lead itfelf, fmall in- 
 deed,. but fuSicient to render it brittle : 
 
 From this it is purified by injecting upon it 
 in fufion a little Mercury-fublimate ; the 
 acid of the fublimate corroding the Lead, 
 which now arifes in fcoriae round the ndes 
 of the veiTel, no longer mifcible with the 
 Gold -Nor is Gold to be perfedtly puri- 
 
 fied by cupellation from Copper : It attradls 
 this metal more ftrongly than it does Lead, 
 If pure Gold be mixed with about one 
 twenty- fourth its weight of Copper, it will 
 fuffer Lead almoft totally to work off, but 
 retain nearly all the Copper The ad- 
 
 mixture of Silver varies its affinity to both 
 thefe metals. Mixed with a little Silver, 
 it parts with Copper, and not with Lead : 
 Mixed with an equal quantity, it parts with 
 both. 
 
42 
 
 Metallic Bodies. 
 
 Gold, cipitaticn. If on the other hand, the quantity of Silver is much greater than 
 w— that of the Gold, Aqua fortis is made u!e of, which diffolves the Silver, and 
 leaves the Gold behind, in form of a black rnafs or powder to be wafhed and 
 -melted with Borax. If the proportions of the two metals are nearly equal, the 
 mixture is melted with fo much irefh Silver, as will make the whole quantity 
 of Silver at lead three times greater than that of the Gold : If the quantity of 
 Silver is much lefs than this, the bed Aqua fortis will not be able to extract 
 it from the Gold : If much greater, the folution or extraction will go on the 
 fader, but the Gold will remain in form of powder, fome particles of which 
 may be in danger of being loft : If it is juft thrice *the weight of the Gold, the 
 Gold retains the form of the original plates : From the Gold making one 
 fourth of the compound, the procefs is commonly called quart ation. This 
 method of parting the two metals is more commodious and effectual than that 
 by Aqua regis ; Aqua fortis diffolving the Silver much fooner than Aqua 
 regis does the Gold ; and the former taking up none of the Gold along with 
 the Silver, whereas the latter almod always diffolves a part of the Silver along 
 with the Gold, efpecially if the Aqua regis is made with an under-proportion 
 of marine Acid. 
 
 Cementation. Gold is likewife purified from Silver by Acids applied in the form of vapour 
 free from phlegm. Thus applied, they extract fmall proportions of Silver as 
 well as large ones ; the Gold being unable to defend that metal againft the 
 fumes, as it does againft the Acid in its liquid ftate. The marine vapours alfo, 
 in this method of application, corrode the Silver as effectually as the nitrous: 
 The only difference is, that when corroded by the nitrous, filch part as may 
 remain in the pores of the Gold is eafily diffolved and wafhed out by water, 
 
 whereas with the marine, it forms a concrete not difibluble in water The 
 
 method of performing the procefs is this. Nitre, or common Salt, (not both 
 at once, for the vapour arifing from the mixture would diffolve the Gold as 
 well as the Silver) is mixed with an equal quantity of calcined Vitriol, by 
 which its Acid is extricated in the fire; and twice its weight of powdered 
 Bricks, to prevent the matter from melting and adhering to the ftirface of the 
 metal. The Gold impregnated with Silver, is flatted into plates ; cleanfed by 
 ignition from any external unftuofity that might impede the aCtion of the 
 acid ; then ftratified and every where furrounded with the mixture in a cru- 
 cible or cementing- pot ; the vefiel clofely covered and luted ; the fire gradu- 
 ally railed to a flight red heat, and kept up for twelve, fixteen or twenty 
 
 hours It is often neceffary to repeat the cementation ; a part of the Silver 
 
 being apt to efcape the aCtion of the fumes, efpecially when the plates are of 
 confiderable thicknefs : The metal, after one cementation, muft be melted 
 and laminated afrefh, before it is committed to another. Thefe kinds of ope- 
 rations were formerly often praCtifed ; but have now in great meafure given 
 place to more advantageous and effectual methods of feparation. The mixture 
 Method of with Sea- Salt is commonly called the regal cement; Gold being the only me- 
 diilinguifhing tallic body [Platina excepted] that is capable of refitting it. 
 
 Gold from The refiftance of Gold to Aqua fortis affords a ready method of diftinguifli- 
 refemble^in * n § t ^ at meta ^ fr° m compofitions refembling it in colour. If a line be drawn 
 colour. with the mafs, upon any fmooth ftone that does not diffolve in acids, a drop 
 
 of 
 
Metallic Bodies. 
 
 of Aqua fortis will take off the mark left by any of the bafe metals, whilft 
 that made by Gold remains untouched. 
 
 If Gold contains Copper, Lead, or other imperfect metallic bodies, along 
 with Silver, it is purified firft from the bafe metal by the teft or cupel, and 
 
 then feparated from the Silver by quartation It is purified alfo from all the 
 
 metals by fufion with Antimony, which abforbs orfcorifies all but Gold. Tin 
 Is molt commodioufly feparated by injecting corrofive Sublimate upon the 
 Gold in fufion- Mercury is difiipated from it by bare ignition. 
 
 Gold is cleanfed from external impurities, by heating it red-hot, and walk- Methods of 
 ing it with weak Aqua fortis, brine of Sea- Sait with Tartar, &c. When pale, cleaniing it 
 the colour, is heightened, by melting it with Copper and afterwards ^ e P ara dng^ t d e ™ £ ^' en _ 
 the Copper ; or by a mixture of Verdigris and Sal Ammoniac with Vitriol j n g ; ts colour, 
 or Nitre (s). Some boil the pale Gold in a folution of thefe Salts made in 
 Vinegar: Others moiften the Salts with Vinegar into the confidence of a 
 pafte, which is fpread upon the Gold, and the metal laid upon burning coals 
 till the mixture is burnt off. The fprinkling of the Salts in powder upon the 
 moiftened Gold, pra<5lifed by fome, does not anfwer fo well. It is faid that 
 a mixture of Gold with one third, or even with half its weight of Silver, 
 acquires, on cementation with Verdigris, the colour of pure Gold. The Silver 
 however is eafily difcovered on the touchftone by means of Aqua fortis : If a 
 line be drawn with the compound metal, a little Aqua fortis, applied upon 
 the parr, will eat out the Silver; and the remaining Gold will appear fpecked 
 and difunited(/), 
 
 II. S 1 L» 
 
 (s) Colour heightened.'] The colour of Gold 
 
 is improved alio by fufion with Nitre ; in- 
 jecting Sal Ammoniac upon it in fufion ; 
 quenching it in urine ; boiling it in a folu- 
 tion of Alum. When Borax is ufed as a 
 flux, it is cuftomary to add a little Nitre or 
 Sal Ammoniac, to preferve it from being 
 made pale by the Borax Juncker re- 
 
 ports, from the Alchymia depudata , that by 
 melting Gold with four times its weight of 
 Copper, feparating the Copper by Aqua 
 fortis unpurified, then melting the Gold 
 with the fame quantity of frefh Copper, and 
 repeating this procefs eight or nine times ; 
 the Gold becomes at length of a deep red 
 puniceous colour, which fuftains the a&ion 
 of Lead, Antimony and Aqua fortis. 
 
 ( t ) Additional article : PLAT IN A.] This 
 metal, faid to be found in the Gold-mines 
 of the Spanifh Weft-Indies, has but lately 
 become known to Europe. In what form 
 it is met with in the mines, we have no 
 fatisfaCtory account : To us, it is brought 
 over in imall white grains, mixed with a 
 
 ferrugineous Sand and fome other foreign 
 matters. It is called by the Spaniards Pla- 
 tina (a diminutive of Plata, Silver) probably 
 from its colour ; for in this refpeff it 
 greatly refembles Silver, though in others 
 it comes nearer to Gold. 
 
 It pofieftes, in effeCl, almoft all thofe 
 properties, which have been hitherto fup- 
 pofed chara&eriftic of Gold, and ftands all 
 the tefts by which that metal has been 
 ufually allayed or refined ; being nearly as 
 ponderous ; equally difioluble in Aqua re- 
 gia, and precipitable by the other metals 
 which diflolve in that menftruum ; equally 
 refilling Aqua fortis, and the other Ample 
 Acids, and the regal cement; being equally 
 permanent and fixed in the fire ; equally in- 
 deftruCtible by Lead and by Bifmuth ; un- 
 affeCted by Nitre and by Sulphur ; incapable 
 of being icorified by the fulphureous part 
 of Antimony, or volatilized by its regu- 
 line. 
 
 Thefe properties, together with the place 
 where it is found, and the .prohibition faid 
 to be laid upon its exportation by the king 
 
 G 2. Ctf 
 
44 
 
 M 
 
 E T A L L I C 
 
 Platina. ofSpain, afford fufficient grounds to pre- 
 fume that the Smiris Hifpanica of the alche- 
 mifts, employed for augmenting Gold, was 
 no other than this Platina or fome mineral 
 containing it; more efpecially as Becher ex- 
 prefsly declares, that this augmentation was 
 really an abufe ; that the Gold fo augmented 
 was pale and brittle ; and that though it 
 flood all the eftablifhed tefts of perfect 
 Gold, yet it would not bear amalgamation 
 with Quickfilver, the Mercury retaining the 
 Gold, and throwing out the Smiris in form 
 of a reddifh powder. Platina mixid with 
 Gold is thrown out in the fame manner ; 
 though it is not eafy by this method to ob- 
 tain a perfect leparation. 
 
 This metal is in fome fmall degree mal- 
 leable ; lets fo when ignited than when 
 cold. Its fpecific gravity is to that of 
 Gold, nearly as 1 8 to 19. The grains 
 cohere in a ftrong fire, but do not melt, or 
 foften, or fenfibly alter their figure ; whe- 
 ther expofed to its adfion in dole velfels, or 
 placed in contact with the burning fuel ; 
 by themfelves, or with the addition of in- 
 flammable, faline, vitreous or earthy fluxes. 
 Compofitions of Sulphur and fixed alcaline 
 Salts, render it fufible in the fire, and fo- 
 luble in water. 
 
 Platina melts perfe&ly with all the me- 
 tals, and occafions remarkable alterations 
 in their colour, texture and hardnefs. It 
 deftroys the malleability of near four times 
 its weight of Tin: With larger proporti- 
 ons, it forms compounds tolerably dudile, 
 but renders the texture of the Tin coarfer, 
 and debafes its colour. All thefe compofi- 
 tions tarnifh in the air; thofe leaft, which 
 have either a very fmall or a very large pro- 
 portion of Platina. 
 
 A fmall quantity is taken up very eafily 
 by Lead : A large one is taken up much 
 more difficultly than by Tin, and fub- 
 fides in great part upon an abatement of 
 the heat. A little quantity ftiffens and har- 
 dens Lead much more than it does Tin ; 
 but a large one does not near fo much di- 
 minifli its malleability. A leafy or fibrous 
 texture, a purplifh or blue colour, or a dif- 
 pofition to quickly acquire this colour from 
 the air, are peculiar to the mixtures with 
 Lead. 
 
 It unites with Silver more difficultly than 
 with either of the two foregoing, and is 
 
 i O D I E S. 
 
 more apt to fubfide from it on an abate- 
 ment of the fire : A part of the Silver is 
 likewife thrown up during the fufion, and 
 adheres to the cover of the crucible in little 
 globules : To this, of all the metals, it 
 difcovers the greateft repugnance. It di- 
 minifhes the malleability of Silver far lefs 
 than that of Lead or Tin, and does not, in 
 whatever proportion employed, fo much 
 aebafe its colour or difpofe it to tarnifh. 
 
 It diminifhes the dudfility of Gold far 
 lefs than that of any other metal : A mix- 
 ture even of equal parts of each may, with 
 proper care, be fomewhat flattened by the 
 hammer. In confiderable proportions, it 
 debafes the colour more than the ufual al- 
 loy, not communicating its own whitenefs, 
 as the other white metals do, but a peculiar 
 dingy hue, readily diftinguiftiable by the 
 eye. In fmall proportions, as one fiftieth, 
 it does not fenfibly injure either the colour 
 or malleability of Gold. 
 
 A large proportion whitens Copper, and 
 renders it very hard and brittle : A fmall 
 one improves its hardnefs, without feemiug 
 to injure its colour, or, fo far as could be 
 judged, its malleability. Thefe mixtures 
 bear a fine polifh ; and do not tarnifh in 
 the air, fo much, orfo foon, as pure Copper. 
 
 It renders caft Iron exceflively hard, in 
 fome degree tough, fufceptible of a fine po- 
 lifh, and not apt to tarnifh. The com- 
 pound, cemented with the Steel-making 
 mixtures, is not changed into Steel ; but 
 fomewhat foftened, and more fo than by the 
 fubftances which foften pure caft Iron. 
 
 It unites with Bifmuth, Zinc, and Regu- 
 lus of Antimony, as perfectly as with the 
 malleable metals. It increafes the hardnefs 
 of the two latter, but not of the former ; 
 difpofes Bifmuth to change its colour in the 
 air, but not the other two. 
 
 Its effects on the compound metals are 
 fimilai to thofe which it produces on the 
 fimple ones. Brafs, it renders white, hard, 
 brittle, fufceptible of a fine polifh, and not 
 liable to tarnifh ; as it does the Copper, 
 and in fome degree the Zinc, of which 
 that metal is compofed. Mixtures of it 
 with Copper and Tin are more apt to tar- 
 nifh than thofe with Copper only, and lefs 
 than thofe with Tin only. 
 
 All the compofitions of Platina with me- 
 tals are more brittle when ignited than 
 when cold. Their fpecific gravity is lefs 
 
 than 
 
Metallic Bodies, 
 
 4.5 
 
 than the medium of the gravities of the two 
 ingredients. All the metals may be made 
 to take up equal their own weight of 
 the Platina ; fome metallic compofitions of 
 Tin, Copper, &c. twice their weight. Se- 
 veral of the mixtures melt, and appear uni- 
 form to the eye, by a moderate heat ; but the 
 union is never perfect without a ftrong one. 
 
 After Platina has thus been brought into 
 fufion by metallic additions, it proves, on 
 feparating the metal, as refractory as at 
 firft. In cupellation with Lead, as foon as 
 the Lead has been worked oft' to a certain 
 point, the matter becomes confident, and 
 can no longer be made to melt, or to part 
 with any more of the Lead. The cafe is 
 the fame in fcorifying Bifmuth from it, or 
 diffipating regulus of Antimony or Zinc; 
 the Platina at length refufing to melt, and 
 defending a part of thofe deftruCtible metals 
 from the atftion of the fire and air. Platina 
 cupelled with Lead, unlefs the button turns 
 out fpongy, is found to be remarkably more 
 ponderous than at firft, notwithftanding its 
 retaining a confiderable portion of that 
 lighter metal : The fpccific gravity of fome 
 of the neater and more folid beads, was 
 very nearly the fame with that of fine 
 Gold. 
 
 Platina diflolves in Aqua regis, very 
 Jlowly and difficultly, into a dark brownifh 
 red liquor ; a few drops of which tinge a 
 large quantity of water cf a fine golden co- 
 lour. Thefolution, duly evaporated, {hoots 
 into deep yellowifli-red Cryftals. It gives 
 no ftain to hot Marble, or to the fkin, 
 ■bones, or other folid parts of animals. Oil 
 of Vitriol, added to the concentrated folu- 
 lion, precipitates the Platina; but makes 
 no change if the liquor is previoufly diluted. 
 The Platina is precipitated by alcalies, and 
 by Sal Ammoniac, in form of a red powder: 
 This, expofed to the fire, becomes blackifh, 
 without fulminating ; wafhed with water, 
 it acquires a fimilar colour, tinging a large 
 quantity of the fluid of a golden hue. None 
 of the fubftances that have been tried occa- 
 fion, fingly, a complete precipitation ; a 
 part of the Platina remaining always dif- 
 iblved. By alternate additions of alcalies, 
 and Sal Ammoniac, or by adding Tin after 
 either of thefe, the whole is thrown down, 
 and the liquor left colourlefs. Volatile al- 
 ealies, added after the precipitation is com- 
 pleted, rediflolve a part of the Platina ; and 
 
 more than they do of Gold by the fame Putina. 
 treatment. The precipitates, thoroughly t __ j 
 edulcorated by boiling water, diffolve in fpi- 
 rit of Salt; much more difficultly and fpar- 
 ingly than thofe of Gold. The precipitates 
 made both with metallic and faline fub- 
 ftances, refill vitrification. 
 
 Solution of Platina does not ftrike a 
 purple colour with Tin ; nor prevent Gold, 
 mixed with it, from ftriking this colour. 
 
 The Platina is not revived from its folution 
 by inflammable fpirits, nor taken up by 
 effential Oils or Aither; and does not pre- 
 vent Gold from being revived by the former, 
 or taken up by the two latter. It is not 
 precipitated by folution of green Vitriol, 
 nor prevents Gold from being precipitated 
 
 by that Salt — Thefe experiments afford 
 
 ready means of diftinguilhing fmall propor- 
 tions of Platina mixed with Gold, or of 
 Gold mixed with Platina ; and of perfedlly 
 purifying or feparating the two metals from 
 one another, 
 
 A more particular account of the princi- 
 pal experiments I have hitherto made on 
 this extraordinary metal, may be feen in the 
 Ph'tlofophical Tranfaflions for the years 1754, 
 and 1757, from whence the foregoing ge- 
 neral refults are extracted. Mr. Scheffer 
 has likewife given fome curious experiments 
 on this metal, which he calls white Gold, 
 in the Kong/. Suenjka vetenfkaps academlens 
 handlingar . The very fmall quantity of 
 
 Platina, which he was furnifhed with, did 
 not permit his carrying thefe experiments 
 to any confiderable length : So far as they 
 go, they agree fufficiently with mine, except 
 in regard to the effeift of Arfenic. He re- 
 ports, that Platina, ftrongly heated, melts 
 in an inftant upon the contact of a very 
 fmall proportion of white Arfenic. I have 
 treated Platina and Arfenic in different ways, 
 with and without inflammable additions, by 
 the moft intenfe fires I was able to excite, 
 without ever obferving it become fluid. 
 
 There was commonly a tendency to fufion 
 on the furface, which appeared in part 
 fmooth, bright, and united : But the inter- 
 nal part of the mafs was conftantly found 
 to confift of unchanged grains of Platina. 
 
 It was the frnallnefs of the quantity, which 
 prevented Mr. Scheffer from obferving, that 
 the fufion was only apparent and fuper- 
 ficiai. 
 
 II. SIL- 
 
Metallic Bodies* 
 
 II. 
 
 I L V E R. 
 
 Silver. 
 
 Its general 
 properties,, 
 du&ility, 
 fixity ; 
 expofed to 
 a burning- 
 glafs. 
 
 Solution in 
 the nitrous 
 Acid, 
 
 C I LV E R (the Luna, Diana, Proferpina, Regina metallorum , of the Chemifts,) is 
 the moft perfect, dudtile, and fixed in the fire, of all metals after Gold ( u ). 
 A fingle grain has been drawn into a wire three yards in length ; and the wire 
 flatted into a plate an inch broad. In common fires, it fuflfers no diminution of its 
 weight; and kept in the vehement heat of a glafs-houfe furnace for a month, 
 it loles no more than one fixty-fourth. In the focus of Tfchtrnhauds large 
 burning-glals, it fmokes for a long while, then contracts a greyifh afh on the 
 furface, and at length is totally difiipated. 
 
 The proper menftruum of Silver is the nitrous acid ; which, if well dephleg- 
 mated, will diflolve equal its own weight: The folution ftains the fkin 
 black (x). Some have thought to increaie the ftrength of the acid, by draw- 
 ing it over from a quantity of frefh Nitre ; and been furprized to find, that in- 
 Read of adling more powerfully upon Silver, it would not now diflolve that 
 metal at all, only corroding it into a white powder; and that on the other 
 hand, it now proved a menftruum for Gold, which before it had no effedt 
 
 upon. 
 
 ( m ) Stiver „] Silver is a foft, flexible me- 
 tal, of little or no elafticity: By hammer- 
 ing it becomes moderately hard, elaftic and 
 fcnorous ; more fo than Gold, lefs than 
 Copper or Iron. Its fpecific gravity is to 
 that of water nearly as i of to i. It melts 
 in a bright red heat, a little fooner than 
 Goid ; and when in fufion, appears a per- 
 fect fpeculum. Like Gold, it continues 
 ductile when heated as well as when cold; 
 lofes a little of its dudfility by fudden cool- 
 ing ; proves brittle when heated by ham- 
 mering; and regains its priftine malleability 
 on being nealed, that is, flightly ignited 
 and fuftered to cool very leifurely. It feems 
 to be perfectly fixed in the greateft degree 
 of culinary fire ; the finall diminution, 
 which in fome experiments of this kind has 
 happened at firft, being apparently not of 
 the Silver itfelf, but of fome other metal 
 with which it had been debafed. 
 
 (a) Solution pains, &c.] It ftains hair, 
 bones, and other folid parts of animals, and 
 different kinds of wood, of all the interme- 
 diate fhades, from a light brown to a deep 
 and luffing black. The liquors commonly 
 fold for ftaining hair brown or black, are 
 r.o other than folutions of Silver in Aqua 
 fortis, fo far diluted with water as not fen- 
 fibly to corrode the hair. 
 
 It gives a permanent ftain likewife to 
 
 fundry ftones; not only to thofe of the 
 fofter kind, as Marble : but to fome of con- 
 fiderable hardnefs, as Agates and Jafpers^ 
 The folution, for this purpefe, fiiould be 
 fully laturated with the metal ; and the 
 ftone, after the liquor has been applied, ex- 
 pofed for fome time to the fun. Mr. du 
 Fay obferves (in a paper upon this fubjedfc 
 in the French Memoirs for the year 1728) 
 that if the folution be repeatedly applied, it 
 will penetrate, in the whitifh Agate or chal- 
 cedony, about one twelfth of an inch : 
 That the tindhire does not prove uniform, 
 on account of veins in the ftone : That the 
 colours thus communicated by art are rea- 
 dily diftinguifhable from the natural, by their 
 difappearing upon laying the ftone for a 
 night in Aqua fortis ; that on expofing it 
 afterwards to the fun for fome days, the co- 
 lour returns : That the folution gave fome- 
 what different tindfures to different ftones ; 
 to the oriental Agate a deeper black than to 
 the common Chalcedony ; to an Agate fpot- 
 ted yellow, a purple; to the Jade-ftone, a 
 pale brownifh; to the common Emerald, an 
 opake black ; to common Granate, a violet 
 unequally deep ; to Serpentine-ftone, an 
 olive ; to Marble, a reddifh, which changed 
 to a purple, and fixed in a brown : That on 
 Slates, Talcs, and Amianthus,, it had no 
 effedt. 
 
Metallic Bodies. 47 
 
 upon. Thefe alterations depend wholly upon the Nitre containing Sea Salt ;Si lvk r. 
 whole Acid is expelled in the diftillation by a part of the nitrous, and forced 
 ■over along with the reft: Pure Spirit of Nitre, drawn over from pure frefh 
 Nitre, diftolves Silver, and leaves Gold untouched, as at firft. 
 
 Solution of Silver, evaporated a little, Ihoots in the cold into Cryftals (_}'), Cryftals. 
 intenfely bitter and corrofive, and hence called by fome fel metallorum , the 
 gall of metals : The cryftallization is promoted by dropping in a little Spirit of 
 Wine before the liquor is let to fhoot. The cryftals, or thefolution infpifiated 
 to drynels, melt in a fmall heat, and form on cooling a dark coloured mafs 
 ftill more corrofive, their phlegm having been difiipated in the fire. This Lunar Caul 
 mafs is the lunar Cauftic or infernal Stone of the fiiops : For the greater con- tlc> 
 veniency of ufing it as a Cauftic, it is commonly caft, in proper moulds, into 
 {lender cylindrical pieces. The Cryftals have been given internally, as purga- 
 tives and diuretics, and hence named Catharticum lunar e, and hydragogum Angeli 
 Bala: They are a medicine of great aflivity, too great to betaken with 
 fafety. 
 
 If folution of Silver be diluted with pure water, a confiderable quantity of Arbor Dianas 
 pure Mercury added, and the whole fet by in a cold place ; there will form by 
 degrees a precipitation and cryftallization refembling a little tree, with its root, 
 trunk and branches, called Arbor Diana, or the philofophic Silver- tree. Le- 
 mery gives another method of making an Arbor Diante, by adding to folution 
 of Silver fome warm diftilled Vinegar (2) — —Silver is precipitated from itsprecipitaticm 
 folution by (a) Copper, Iron, Tin and Zinc. Copper is commonly made of Silver. 
 
 choice 
 
 (y) Cryftals.] The Cryftals of Silver (hoot 
 into thin, colourlefs, tranfparent plates, ap- 
 proaching to a triangular figure. They 
 readily diflolve in water 3 and by the affift- 
 ance of warmth, in Spirit of Wine. Ex- 
 pofed for fome time to a moderately ftrong 
 fire, they part by degrees with all the acid, 
 and return into Silver again 5 though fcarce- 
 ly without fome little Tofs, unlefs borax or 
 alcaline fluxes are added, to colled! and re- 
 unite the particles of the metal — If laid on a 
 burning coal, the nitrous acid, deflagrat- 
 ingwith the inflammable matter, as this acid 
 in all its combinations does, is quickly con- 
 fumed, and the Silver revived. I have not 
 obferved in this experiment any confider- 
 able volatilization of the Silver 5 though in 
 the Apt a natura curiojorum , tom. vi. there is a 
 remarkable hiftory of Silver diflolved in the 
 nitrous acid being volatilized in clofe veffels 
 by means of Charcoal. Four ounces of 
 pure Silver being diflolved in Aqua fortis, 
 and the folution fet to diftil in an earthen 
 retort 3 a white tranfparent butter arofe into 
 the neck, and nothing remained behind : 
 By degrees the butter liquefied, and palled 
 
 down into the phlegm in the receiver: The 
 whole being now poured back into the re- 
 tort, the Silver arofe again along with the 
 acid : On adding Sea-Salt to this volati- 
 lized folution, the Silver was precipitated 
 into a Luna Cornea. The volatilization 
 being attributed to the liquor having ftood 
 in an elaboratory where Charcoal was bring- 
 ing in, the experiment was repeated with a 
 frefh folution of Silver mixed with a little 
 powdered Charcoal ; with the fame event. 
 
 (z) Vegetations.] Another kind of artifi- 
 cial vegetation, as it is called, may be pro- 
 duced, by fpreading a few drops of folution 
 of Silver upon a glafs-plate ; and placing 
 in the middle a fmall bit of any of the me- 
 tals that precipitate Silver, as particularly 
 of Iron. The Silver quickly concretes into 
 curious ramifications all over the furface of 
 the plate. Other metallic folutions afford 
 alfo vegetations on the fame treatment 3 but 
 none fo elegant ones as that of Silver. 
 
 (a) Precipitation of Silver . ] Silver is pre- 
 cipitated from Aqua fortis by all the metals 
 
 which 
 
Metallic Bodies. 
 
 48 
 
 Silver, choice of, the Precipitate obtained by that metal being the pureft, though 
 it is never entirely free from fome portion of the Copper. This calx is em- 
 ployed for cold filvering ; mixed with Nitre, Sal Ammoniac and common 
 Salt, in the proportion of one part of each of the Salts to two of the lunar 
 Calx : Some, inftead of the Precipitate, take Silver leaf, with equal its weight 
 of Creme of Tartar, and the fame quantity of common Salt. 
 
 The marine acid does not diffolve Silver .(£), but precipitates it from the 
 nitrous. Upon adding, to a folution of the metal made in Aqua fortis, either 
 the pure acid of Sea-Salt, or the Salt in fubftance, or Sal Ammoniac, the 
 liquor inftantly becomes milky, and on Handing depolkes the Silver now 
 
 combined 
 
 Combination 
 of Silver with 
 the marine 
 acid. 
 
 which diflolve in that acid ; readily and co- 
 pioufiy at firft ; but fiowly and "difficultly 
 towards the end. The menftruum gene- 
 rally retains fome portion of the Silver, as 
 the Silver almoft always does of the metal 
 which precipitated it — —The refiners, for 
 recovering the Silver from Aqua fortis after 
 parting, employ Copper. The folution, 
 diluted with water, is put into a copper- 
 veffel, or into a glafs one with thin plates 
 of Copper, and fet in a gentle warmth : 
 The Silver begins immediately to feparate 
 from the liquor in form of fine grey feales 
 or powder ; a part of the Copper being dif- 
 folved in its place, fo as to tinge the fluid 
 more and more of a bluifh-green colour : 
 The plates are now and then fhaken, that 
 fuch part of the Silver, as is depofited upon 
 them, may fall off and fettle to the bottom. 
 The digeftion is continued, till a frefh, 
 bright plate, kept for fome time in the warm 
 liquor, is no longer obferved to contract any 
 powdery matter on the furface ; when the 
 liquor is poured off, and the Precipitate 
 waihed with frefh parcels of boiling water. 
 The finall portion of Silver, which the acid 
 commonly fliil retains, may be precipitated 
 by common Salt : The Copper, which the 
 Silver retains, may be in part fcorified and 
 feparated by fufion with Nitre. It is ob- 
 fervable, that though the Acid in this pro- 
 cefs, faturates itfelf with the Copper in pro- 
 portion as it lets go the Silver j yet the 
 quantity of Copper, which it takes up, is 
 not near fo great as that of the Silver which 
 it depofites. One dram of Copper will pre- 
 cipitate three of Silver, and faturate all the 
 acid that held the three drams diffolved. 
 
 Abforbent earths, as Chalk or Quick- 
 lime, throw down a part of the Silver, but 
 kave a very confiderable part fufpended in 
 
 the liquor. If the earth be moiftened with 
 the folution into the conlillence of a paftc,. 
 and expofed to the fun, it changes its white 
 colour to a dark purplifh black : Diftindt. 
 charadfers may be exhibited on the matter, 
 by intercepting a part of the fun’s light by 
 threads, flit paper, Ur. placed on the out- 
 fide of the glafs. Culinary fire does not 
 aftedb its colour : After the mafs has been 
 exficcated by this, it changes as before 
 upon expofure to the fun. 
 
 Volatile aicaline Spirits, added to a folu- 
 tion of Silver, precipitate little. Pure fixed' 
 Alcalies, and Alcalies, rendered caufiic by 
 Quick-lime, throw down the whole. Fixt 
 Aicalies impregnated with inflammable mat- 
 ter by calcination with animal coals, occa- 
 fion at firft a confiderable precipitation, but 
 if added in larger quantity, take up great part 
 of the metal again. Mr. Marggraf relates, 
 that edulcorated calces of Silver totally dif- 
 folve both in a lixivium of thefe Alcalies and 
 in volatile Spirits ; and that the marine acid 
 precipitates the Silver from the volatile, 
 
 but not from the fixed aicaline folution 
 
 Kunckel reports, that the calx precipitated 
 by volatile fpirits made with Quick-lime, 
 fulminates or explodes in the fire : And 
 that by infpiffating a folution of pure Silver, 
 melting the dry refiduum, pouring on it 
 Spirit of Urine fuperfaturated with Salt, and 
 fetting the mixture in a gentle warmth, a 
 blood-red mafs is produced, fo tough as to 
 be wound about the fingers. 
 
 (A) Marine acid.] Strong Spirit of Salt 
 corrodes leaf Silver into a white powder : 
 On filings or larger mafies, it has no effedb. 
 The highly concentrated acid, applied, in 
 the form of vapour, to mafies of Silver at 
 the fame time ftrongly heated, readily cor- 
 rodes 
 
Metallic Bodies. 49 
 
 combined with the marine acid into a white powder. This, when furRciently Silv’er. 
 wafhed with water, proves infipid, though containing fo much acid as to k — 
 weigh one fourth more than the Silver employed. It does not diffolve in Luna Coniea * 
 water, Spirit of Wine, Aqua fords or Aqua regis ; but is in forne frnall degree 
 adted on by the vitriolic acid. It melts in the fire as foon as it begins to grow 
 red-hot, and on cooling forms a ponderous brownifh mafs, which if caft into 
 thin plates, proves femi-tranfparent and fomewhat flexible, like horn-, whence 
 its name Luna Cornea. A flronger fire does not expel the acid from the Sil- 
 ver-, the whole concrete either arifing in fumes, or finking through the veil'd, silver volatf. 
 without any reparation of its parts: It may be fublimed like Arfenic, withlized. 
 which it has in many refpedts a great analogy. If mixed with fixt alcaline 
 Salts, or inflammable fubftances as Oil or Tallow, and melted in a crucible, 
 the acid is abforbed or expelled, and the Silver recovered pure(r). 
 
 The 
 
 rodes them. Thus if filings, grains or 
 plates of the metal be mixed with about 
 twice their weight of Mercury fublimate, 
 and expofed to a moderate fire in a retort or 
 other proper veffel ; the marine acid of the 
 fublimate will be abforbed by the Silver, 
 and form with it a Luna Cornea ; whilft 
 the Mercury, now difengaged from the 
 
 acid, diftils in its running form -The 
 
 marine acid is commonly fuppofed incap- 
 able of diflolving Silver into a liquid flate. 
 Henckel reports, in his tra£f de appropriation t 
 that if the red Silver Ore (which confifts of 
 Silver intimately blended with red Arfenic) 
 be digefted in Spirit of Salt, the Silver will 
 be extradled and kept permanently dif- 
 folved. 
 
 (r) Luna Cornea — Silver recovered pure.] 
 Luna Cornea is moft commodioufly pre- 
 pared, by diluting a folution of Silver with 
 ten or twelve times its quantity of water, 
 and* adding by degrees a folution of Sea- 
 Salt, fo long as it occafions any turbidnefs 
 or milky hue. The whole is then to be 
 fet by till the white powder has fettled ; 
 when the clear liquor is to be poured off, 
 and the precipitate wafhed with frefii 
 parcels of boiling water. If the Silver 
 contained any portion of Copper, which it 
 always does after the common methods of 
 purification, that metal will here be fepa- 
 rated, and left diffolved in the liquor ; pure 
 Sea-Salt precipitating no metallic body but 
 Silver, Lead, and Mercury. Hence Silver 
 is brought by this procefs to a degree of 
 purity fcarce procurable by any other known 
 means. 
 
 The Silver may be recovered from the 
 Luna Cornea, by fufion with alcaline and 
 inflammable fluxes as dire&ed by the au- 
 thor, or with certain metallic bodies: But 
 
 in thefe operations, there happens always a 
 confiderahle lofs of the Silver ; a part of the 
 volatile calx being diffipated by the fire, be- 
 fore the alcali or metal can abforb its acid. 
 Mr. Marggraf has difcovered a method of 
 reviving the Silver with little or no lofs ; 
 Mercury, affifted by volatile Salts, imbibing 
 it by trituration without heat. One part 
 of Luna Cornea and two of volatile Salt are 
 to be ground together in a glafs mortar, 
 with fo much water as will reduce them 
 into the confiftence of a thin pafte, for a 
 quarter of an hour or more : Five parts of 
 pure Quick-filver are then to be added, with 
 a little more water, and the triture con- 
 tinued for fome hours. A fine amalgam 
 will thus be obtained ; which is to be 
 wafhed with frefh parcels of water, fo long 
 as any white powder feparates. Nearly the 
 whole of the Silver is contained in the amal- 
 gam, and may be recovered perfectly pure 
 by diftilling off the Mercury. The white 
 powder holds alfo a frnall proportion, fepa- 
 rable by gentle fublimation : The matter 
 which fublimes is nearly fimilar to Mercu- 
 rius dulcis. 
 
 Luna Cornea totally difiblves in volatile 
 alcaline Spirits, without any feparation of 
 the metal — -—Expofed to the fire in a clofe 
 copper veffel, it penetrates the Copper, and 
 tinges it throughout of a Silver colour—— » 
 Kunckel obferves, that when carefully pre- 
 pared, melted in a glafs veffel, and fuffered 
 to cool flowly (to prevent its cracking,) it 
 H proves 
 
5 ^ 
 
 Silver. 
 
 Combination 
 with the vi- 
 triolic acid. 
 
 Amalgama- 
 
 tion. 
 
 Silver with 
 Sulphur, 
 
 Purification of 
 Silver. 
 
 Tinftura 
 
 Lunte. 
 
 Silver boiled 
 white. 
 
 Metallic Bodies. 
 
 The vitriolic acid alfo precipitates Silver from the nitrous ; but does not 
 a<5t upon Silver In its metallic date, unlefs highly concentrated and affifted by 
 a boiling heat(d). The marine acid precipitates Silver from the vitriolic, in. 
 the fame manner as from the nitrous. 
 
 Mercury very readily amalgamates with Silver leaf. It eafily unites like- 
 wife with the calx of Silver precipitated by Copper j but does not couch the 
 calces precipitated by Salts. 
 
 The vapours of fulphureous folutions ftain Silver yellow or black. Sulphur 
 melted with Silver debafes its colour to a leaden hue, renders it more eafily 
 fufible than, and makes it flow fo thin, as to be apt in a little time to penetrate 
 the crucible : In a heat juft below fufion, a part of the Silver ihoots up, all over 
 the furface, into capillary efflorefcences. Aqua fortis, the folvent of pure 
 Silver, does not aft upon the Silver in this compound ; but fixt alcaline Salts,, 
 the menftruum of Sulphur, may be made to abforb that ingredient j the Al- 
 cali however, when combined with the Sulphur, will take up the Silver again. 
 If the fulphurated Silver be mixed with Mercury fublimate, and expofed to the 
 Are, the Mercury of the fublimate will unite with the Sulphur, and carry it 
 up in the form of Cinnabar ; whilft the marine Acid of the fublimate unites 
 with the Silver into a Luna Cornea which remains at the bottom of the glafs. 
 Fire alone, continued for fome time, is fufficient to expel the Sulphur from 
 Silver. 
 
 Silver is purified from the bafer metals by cupellation with Lead. It always 
 retains however after that operation fome fmall portion of Copper, fufficient to 
 impregnate volatile Spirits with a blue tinfture, which fome have erroneoufly 
 fuppofed to proceed from the Silver itfelf. It is purified from this admixture 
 by melting it twice or thrice with Nitre and Borax : The Scorite, on the firft: 
 fufion, are commonly blue ; on the fecond, green ; and on the third, white, 
 a mark of the purification being completed. But the moft effeflual purifica^- 
 tion is the revival of Silver from Luna Cornea. 
 
 Silver is purified and whitened externally by boiling in a folution of Tartar 
 and common Salt. This is no other than an extraction of the cupreous par- 
 ticles from the furface of the Silver, by the acid of the Tartar acuated with 
 the common Salt. 
 
 The 
 
 proves clear and tranlparent, may be turned 
 m a lathe, and formed into elegant figures. 
 He fuppofes this to be the preparation 
 which gave rife to the notion of malleable 
 Glals. 
 
 (d) Silver with the vitriolic acid.) Oil of 
 Vitriol, aflifted by a boiling heat, corrodes 
 into a faline mafs half its weight of Silver 
 filings. This compound difcovers a re- 
 markable attraction to Mercury : It coagu- 
 lates and hardens as much Quick-filver as 
 the acid weighed at firft : If the hard con- 
 crete be diluted with frefh acid, it melts 
 eafily in the fire, and does not part with the 
 
 Mercury in the greateft heat that glafs vef- 
 fels can fupport. The vitriolic acid by it- 
 felf ftrongly retains Mercury ; but not near 
 fo much fo, as when thus combined with: 
 Silver. 
 
 Silver thus corroded by the vitriolic acid, 
 or precipitated by it from the nitrous, may 
 be in great part diflblved into a liquid ftate, 
 by cautioufly applying a very little water at 
 a time ; and more effectually, by repeating 
 the coCtion in frelh Oil of Vitriol. The 
 calx precipitated from this folution by the 
 marine acid is faid by Kunckel to be more 
 volatile and penetrating than the common. 
 Luna Cornea. 
 
Metallic Bodies. 51 
 
 The Silver employed for coins and utenfils, has always an admixture oFSilver.' 
 Copper, which improves its hardnefs and fonoroufnefs. Its degree of finenefs 
 is expreffed among us by ioths or half ounces : A march, contains fixteen half 
 ounces: The Silver is laid to be of fixteen loths, when all the fixteen half 
 
 ounces are pure Silver ; of fifteen, when only fifteen half ounces are pure Silver 
 
 and the other Copper, &V. Mofc of the other metallic bodies render it 
 
 brittle : One part of Tin deftrcys the malleability of above an hundred parts 
 of Silver; and Regulus of Antimony has this effect in a ftill greater degree.. 
 
 Both Regulus of Antimony and Arfenic render a part of the Silver volatile in 
 the fire ( e ). 
 
 Silver is found in all countries ; but moft plentifully in America, parti- Where found, 
 cularly in Peru and Potofi, from whence large quantities are brought annually 
 into Europe. It is met with either in its perfect metallic ftate, or in the form 
 of Ore, or blended in the Ores of other metals. 
 
 Native malleable Silver occurs not unfrequently, in different Stones, Earths, Native Silver, 
 and in moft kinds of Sands ; in fmall pieces, of different figures, chiefly fila- 
 ments or fcales. It generally contains fomewhat arfenical, but never holds 
 any Gold, though native Gold is feldom free from Silver. 
 
 The 
 
 (<?) Silver with other metals .] Its colour is 
 debafed by all the metals, and its malleabi- 
 lity greatly injured by all but Gold and 
 Copper : The Englifh ftandard Silver con- 
 tains one part of Copper to twelve and one 
 
 third of pure Silver Silver difcovers, in 
 
 fome circumftances, a great attraction to 
 Lead ; though it does not retain any of that 
 metal in cupellation, as Gold does. If a 
 mixture of Silver and Copper be melted 
 with Lead, in certain proportions, and the 
 compound afterwards expofed to a moderate 
 fire, the Lead and Silver will melt out to- 
 gether, bringing very little of the Copper 
 with them : By this method, Silver is often 
 feparated from Copper in the large works. 
 The effect does not depend wholly upon the 
 different fufibility of the metals; for if Tin, 
 ■which is ftill more fufible than Lead, be 
 treated in the fame manner with a mixture 
 of Copper and Silver, there will be no eli- 
 quation ; the three ingredients, here, ftrong- 
 ]y attracting one another, fo as to come all 
 into fufion together. Again, if Silver be 
 melted with Iron, and Lead added to the 
 mixture ; the Silver will forfake the Iron to 
 unite with the Lead, and the Iron will float 
 by itfelf on the furface. 
 
 Silver with vitreous matters .] Precipitates 
 or calces of Silver melted with vitreous 
 
 H 
 
 fubftances, impart to them a yellow colour. 
 Kunckel obferves, that when the glafs is 
 ftrongly ftirred in fufion with an Iron rod, 
 or blown into veffels, it changes its uniform 
 tinge into an opake milkinefs, variegated 
 with yellow and other colours : The pre- 
 paration of Silver he employs is Luna Cor- 
 nea. This, or the other precipitates, 
 fpread upon a glafs plate, adhere and ftain 
 it yellow by ignition without fufion : Hence 
 their ufe in painting on Glafs. 
 
 The moft beautiful yellow enamel for 
 Porcelane hitherto difcovered (communi- 
 cated in the Phil. Tranf. and the Swedifh 
 Acts) owes its colour to Silver. A Glafs 
 made from three parts of Litharge and one 
 of Flint, is reduced into grofs powder, and 
 a folution of about one twentieth its weight 
 of Silver poured upon it : The mixture is 
 ftirred together, exficcated and melted a- 
 gain, and when in thin fufion poured out. 
 This compofition, ground into fine powder, 
 is applied on the Porcelane previoufly 
 heated ; and the ignition continued, under 
 a muffle, till the powder melts, which is 
 known by its gliftening. The ware is then 
 taken out of the furnace, and, whilft it 
 continues red-hot, held over the fmoke of 
 burning vegetables, which calls forth the 
 beautiful colour. 
 
 2 
 
52 Metallic Bodies. 
 
 Silver. The principal ores of Silver are, (i.) Ganfekotbig ertz> goofe-dung ore, fa 
 — v— ' called from its colour ; this is furrounded, and penetrated with effiorefcences 
 
 Oujs of Sil- 0 £ capillary Silver. (2 .) Glafertz-, compofed of Silver and Sulphur. This 
 ore is of an irregular figure, fometimes cubical, fometimes of eight or more 
 Tides. When pure, it may be hammered or cut almoft like Lead ^ but if pe- 
 netrated by foreign matters it falls in pieces from a blow : The pieces fingly 
 prove malleable. There are fome forts brittle throughout, probably from an 
 admixture of Arfenic. Its colour is blackifh, fometimes brighter, and fome- 
 times darker: There is one fort of a grey colour almoft like the fallow ore, 
 but differing from that ore in containing no Copper. It melts in the fire as 
 foon as it begins to grow red-hot. Its yield of Silver is variable, but always 
 large, amounting commonly to about three fourths of its weight. (3. ) Hor - 
 nertz, horn ore ; externally irregular, internally compofed of fine leaves laid 
 together and femi-tranfparent like horn. It yields, like the foregoing, both 
 to the hammer and the knife. Its colour is whitifh, yellowifh or brownifh : 
 It is commonly foul on the outfide, but may be eafily diftinguifhed by cutting 
 or bending it. In the fire it emits both an arfenical and fulphureous fume \ 
 and commonly affords two thirds its weight of Silver. (4.) Rothgulden ertz^ 
 red Silver ore, is fometimes of a deep tranfparent red, and fometimes darker. 
 It is diftinguifhed from Cinnabar, by its colour inclining not to an aurora or 
 brick red, but to the garnet or ruby red, or a purple red ; though there are 
 red Silver ores alfoof a dull brick hue : The colour of Cinnabar is improved, 
 but that of the Silver ores debafed, by grinding them into fine powder. This 
 ore is very ponderous, melts in the fire before it becomes red-hot, and emits 
 thick fumes fmelling ftrongly of Arfenic. It confifts of Silver and Arfenic, 
 with a little Sulphur ; and with thefe ingredients, or with equal parts of Arfe- 
 nic and native Silver, it may be imitated by art. The quantity of Silver in 
 the deep red forts is commonly from fixty to lixty-two pounds on the hundred ; 
 The yield of the darker kinds is inconftant : Thefe laft hold commonly a little 
 Iron. (5.) IVeiJfguldenertz, white Silver ore, is of a bright grey colour, pon- 
 derous, and brittle. When pure, it contains feven pounds of Silver on the 
 hundred, but a larger quantity of Copper. It confifts of Silver, Copper, An- 
 timony, Arfenic, and Sulphur. Several forts contain likewife Iron, and hold 
 but very little Silver, as two ounces on the hundred weight : Thefe are of a 
 paler and brighter colour than the others, and called plain fVeiffertz, white ore. 
 The white Silver ores have a great refemblance in colour to the paler cobalts *, 
 thefe laft however are fenfibly whiter, and incline a little, like Bifmuth, to a 
 reddifli or yellowifh caft. (6.) The fahlertz and fahlkupferertz , fallow ore 
 and fallow Copper ore, are ranked among the ores of Silver, though they be- 
 long more properly to thofe of Copper. Their colour is a dark grey. They 
 are found among, and fometimes blended with Copper ores and Copper pyritae. 
 They hold from four ounces to fome pounds of Silver upon the hundred. 
 (7.) Federertz , feather ore, is compofed of extremely fine fibres or hairs: It 
 holds two ounces of Silver on the hundred weight, and contains both Arfenic 
 and Sulphur, for it yields on fublimation a yellow Arfenic. (8.) Rnfs, footy 
 ore, confifts of a fine, foft, black duft, which is commonly lodged in clefts : 
 it is very rich in Silver, yielding fometimes half its weight. 
 
 5 
 
 Silver 
 
Metallic Bodies, 53 
 
 Silver is extracted from its matrices by amalgamation with Mercury, and Si lver, 
 from its true ores by fufion, or by fcorification with Lead in the fame manner <«— 
 as Gold (/). 
 
 CLASS II. Imperfect Metals. 
 
 Malleable metals ; — refifiing the fire in clofe ‘vefiels 3 — in open ones , calcin- 
 ing 3 — when calcined , or corroded by Acids , not revivable again into their 
 metallic form without the addition ofi infiammable matter. 
 
 T HESE metals appear actually to contain an inflammable principle, j MP Met 
 which is burnt out in the calcination, and extracted from them by acids. Bodies 
 Nitre, which deflagrates with and diflipates the inflammable principle where- i ^ 
 ever it is to be found, deflagrates with the imperfedt metals, and thus occafions Contain an 
 inftantly the fame change that fire alone would more llowly produce : Some 0 f inflammabIe 
 thefe metals emit vifible flames by themfelves. 
 
 The phlogiftic principle is the fame in one metal as in another, in metals as Their inflam 
 in other bodies, in the mineral as in the vegetable and animal kingdoms, mablepartthe 
 When metals, by the lofs of their own phlogifton, have been changed into a feme with that 
 calx or vitreous mafs ; the introduction of any other inflammable matter, of , ve 2 eta ' Dles 
 from vegetables or animals, Charcoal, Refins, Oils, Fats, (Ac. inftantly re- an animals ‘ 
 ftores their metallic appearance, and all their priftine qualities. 
 
 The calx differs greatly in different metals: It is on this, that the diftin- Their other 
 guifhing characters of each particular metal depend, the calx of one metal principles, 
 forming always with phlogifton no other than the fame metal again. Thefe 
 calces are fuppofed to confift of a certain fixed vitrefcible earth, and a more vo- 
 latile 
 
 (f) Extraction of Silver from the ore.] In 
 the mines of the Spanifh Weft Indies, the 
 Silver is for the moft part native, or only- 
 embedded in earths and ftones, fo as to be 
 feparable by comminution, ablution, and 
 amalgamation, nearly in the fame manner 
 as Gold. The method of conducing the 
 procefs is particularly defcribed by Alonfo 
 Barba. 
 
 The proper ores of Silver are moft com- 
 mon in Germany : The black malleable 
 ore, the fecond of thofe above enumerated, 
 is the only one that has been met with in 
 England, and this but rarely. The Silver 
 is extradted by calcination and fufton. The 
 Sulphur and Arfenic, (one, or other, or 
 both of which, are blended in all the true 
 ores of Silver) are totally diflipable by fimple 
 calcination ; Silver having little affinity 
 with thofe minerals, and parting with them 
 more readily than any of the bafer metals 
 does: The Silver may afterwards be fepa- 
 rated from the remaining earthy or ftony 
 
 matters, by fufion or fcorification with 
 Lead, which anfwers the fame purpofes 
 here as in the extradtion of Gold from its 
 ores or matrices, fee page 40. Silver may 
 likewife be got out from the ore, by fufio.n. 
 with a large portion of Lead without calci- 
 nation, and in forne cafes to better advan- 
 tage than when that procefs is premifed : 
 For Lead abforbs from this metal both 
 Arfenic and Sulphur ; and Arfenic remark- 
 ably promotes the vitrification of Lead, and 
 forms with it a glals far more adtive as a 
 flux for refractory matters than the fimple 
 glafs of Lead. 
 
 Moft of the Englifh Lead ores contain 
 fome portion of Silver 3 and fome of them 
 fo much as to be worked for this metal to 
 advantage : Thofe- of Cardiganfhire are faid 
 to yield from ten to twenty pounds on the 
 tun. Thefe are firft run down as other 
 Lead ores ; and the Silver afterwards ex- 
 tracted from the Lead, by working aft the 
 Lead upon a teft. 
 
54 Metallic Bodies, 
 
 Imp. MET.latUe principle called me. curia!. When metals have been but barely calrned. 
 Bodies, tney have loft only their phlogifton, and are recoverable by the introduction of 
 U — ■y— - 1 frefh phlogifton : A more thorough calcination, by long continuance of fire or 
 by additions, diffipates a part of this mercurial principle ; and as no method has 
 been difcovered of iupplying it by art, the quantity of metal revivable will be 
 proportionably lefs. The procel’s is capable of being carried fo far, that no 
 metal at all fhall be recovered, and that the calx lhall differ but little from a 
 mere earth. 
 
 The perfect metals, of the foregoing clafs, though not refolubte by thefe 
 operations into any diflimilar parts, are fuppofed, from analogy, to confift of 
 the like principles. 
 
 I. L E A D. 
 
 L ^ a d. LEAD, Saturn , is a pale or livid white metal; foon lofing its brightnefs 
 ■_ ' in the air, and contracting a blackilh or greyish alh colour ; very foft and 
 
 Gravity, flexible (£) ; unelaftic and unfonorous , the heavieft of all metallic bodies but 
 Gold, Quickfilver [and Piatina] : It is upwards of eleven times heavier than 
 an equal bulk of water. 
 
 Fufibility, It melts in a very fmall degree of fire, long before it grows red-hot : In 
 a ftrong red heat, it boils, and emits vifible fumes (b). It lofes of its 
 Granulation* malleability in proportion as it is heated : By nimble agitation, when it is juft 
 
 ready* 
 
 (g) Lead— flexible , &c.] Lead is the fofteft 
 and moft flexible of all metallic bodies ; 
 eafily cut with a knife, fhaved with a plane, 
 grooved for windows by being drawn through 
 the glazier’s vice, flatted, by palling be- 
 twixt wooden rollers, into large thin Iheets. 
 When broke by repeated bendings, back- 
 wards and forwards, each piece appears 
 drawn out fmooth to an edge, like the frac- 
 ture of well nealed Gold or Silver. It is 
 rot however du&ile to any great degree, 
 either in the form of wire or of leaf ; in this 
 refpeCl coming far fhort of all the other 
 malleable metals. 
 
 Some have preferred, for mechanic ufes, 
 the milled Lead, or flatted Iheets, to the 
 call: ; as being more equal, fmooth, and 
 folid. But whatever advantages of this 
 kind, the milled fort may appear to have at 
 firft, they are not found to be very durable. 
 When the Lead is ftretched between the 
 rollers, its cavities mull neceflarily be en- 
 larged : The particles of metal, that may 
 be fqueezed into them, can have no union 
 or adhefion with the contiguous particles ; 
 and of confequence mull be liable, from 
 bending, blows, jarrs, or other flight ex- 
 ternal caufes, to Hart out again, and leave 
 the mafs fpongy and porous. 
 
 Lead yields the dulleft and weakeft found 
 of all metallic bodies. Reaumur obferves, 
 that it is rendered fonorous, by calling a 
 fmall quantity into a fpherical or elliptical 
 fegment, as in the bottom of an Iron ladle : 
 from hence he conjectures, that the found 
 of the fonorous metals might be improved, 
 for the bells of clocks, &c. by giving them a 
 fimilar form. 
 
 (b) Fufibility of Lead.] It melts a little la- 
 ter than Tin or Bifmuth ; much fooner than 
 any other metal ; about the five hundred 
 and fortieth degree of Fahrenheit’s thermo- 
 meter. The plumbers call thin ilieets of 
 Lead upon a table or mould, covered with 
 a woollen and above this a linen cloth, 
 without burning or fcorching the cloths : 
 The melted Lead is received in a wooden 
 cafe without a bottom, which being drawn 
 down the Hoping table by a man at each 
 fide, leaves a fheet, of its own width, and 
 more or lefs thin according to the greater or 
 
 lefs celerity of its defce. t For thick 
 
 plates, the table is covered with nroillened 
 land, and the liquid metal conduCled evenly 
 over it, by a wooden ftrike which bears on 
 a ledge at each fide. 
 
Metallic Bodies. 55 
 
 ready to melt, or when returning from a fluid to a confident ffate, it may be L e a d-. 
 divided into fmall grains or powder. Granulated Lead is commonly prepared, 
 by pouring the melted metal into a wooden box rubbed on the infide with 
 Chalk, and ftrongly Ihaking it till it fets or becomes folid : When large 
 quantities are prepared, a wooden trough is made ufe of. It is formed into Shot, 
 round granules or fhot, by pouring the melted Lead into cold water, through 
 a perforated plate •, a little Orpiment being added to the metal in fuflon ; this 
 improves its hardnefs, and makes it run more regularly into globules without 
 drawing a tail. 
 
 Lead when juft become fluid, looks bright like Quickfilver ; but prefently Calcination, 
 eontratfts on the furface a varioufly coloured powdery pellicle. Some have 
 fuppofed that this was an heterogeneous fubftance ; and that the Lead, by its 
 feparation, became purer. But after this imaginary purification, it will ftill, 
 upon continuing the fire, exhibit a pellicle as at firft : If this is taken off, or 
 
 the metal ftirred, fo as to expofe a frelh furface to the air, a new one will 
 arile, till by degrees the whole quantity is changed into a dufky powder or 
 calx, called plumbum ujlum. The injection of a little fat, charcoal powder, or Revival of the- 
 other inflammable matters, prevents this change, and readily revives the calx calx, 
 into Lead again, notwithftanding Boerhaave’s aflertion that the calx of Lead 
 is very hard to reduce (z). 
 
 Calx of Lead expofed to the fire in a furnace fo contrived as that the flame Mafticot aad 
 may play upon its furface, becomes white, yellow, and at length of a bright Minium, 
 red colour ; hence the yellow Lead or Mafticot, and the red Lead or Minium 
 of the painters. Some fuppofe the converfion of Lead into Minium to be an 
 effebt of Ample calcination, produced by the heat abting through the fides of 
 the veil'd j but no degree of heat will change the calx to a red colour, without 
 the immediate contabl of fmoky flame. The metal acquires, in this opera- 
 tion, an increafe of its weight, nineteen pounds of Lead yielding twenty 
 
 pounds 
 
 feen innumerable globules of Lead thus re- 
 vived in the middle of glafs-ftoppers above 
 an inch thick, without the leaft vifible crack 
 or erofion of the furface. 
 
 Wafers are coloured red by the red calx 
 of Lead called Minium, On holding a 
 Wafer barely in the flame of a candle, its 
 Lead is prefently reduced, and runs dowrv 
 in drops. 
 
 The calces and glafs of this metal abforb 
 the inflammable principle even from fome 
 other metallic bodies. If glafs of Lead be 
 melted in an Iron veflel, or ftirred in fuflon 
 with an Iron rod, great part of the Lead 
 will refume its metallic form, a proportion- 
 able quantity of the Iron fcorifying. 
 
 It is faid, that Lead, recovered from its 
 calces, proves fomewhat harder and whiter, 
 than at firft, and lefs fubjebf to tarnilh in the 
 air. The difference, if any, is certainly 
 very fmall,. 
 
 (i) Calx of Lead revived.'] The calces and 
 the glafs of Lead are extremely eafy of re- 
 vival j more fo than thofe of any other me- 
 tal. 
 
 Common Flint glafs contains a large pro- 
 portion of vitrified Lead : I have extracted 
 from it one fourth its weight of perfect mal- 
 leable Lead. If a piece of this glafs be 
 furrounded in a crucible with Soot, pow- 
 dered Charcoal, or other like inflammable 
 matters, and cemented for fome time with 
 a fire infufficient to melt it, the Lead will 
 be revived throughout the whole internal 
 fubftance of the glafs, into little drops : If 
 the matter is brought into fuflon, the Lead 
 fubfides, collected into one button at the 
 bottom. This experiment affords a remark- 
 able inftance, not only of the eafy reduci- 
 bility of Lead, but of the penetrability of 
 Glafs, a fubftance which is looked upon as 
 impervious to all kinds of fumes. I have 
 
5 6 
 
 Metallic Bodies. 
 
 Litharge, 
 
 Glafs of 
 Lead. 
 
 Lead, pounds of Minium- The largeft quantities of Minium are made atVenice, 
 
 and in England. The Venetians employ fur the beft fort, called minio fine y 
 CerufFe or white Lead ; for the middling fort, minio mefan , the refufe plates of 
 Lead remaining after the making of Cerufie : The word; kind, minio or dinar e , 
 is prepared from Litharge (k). 
 
 If Lead be urged with a bright red heat, it changes by degrees into a yel- 
 low, flaky fcoria, called Litharge, of a paler or deeper colour according to the 
 degree of fire it has undergone: The paler fort is dillinguifhed by the name of 
 Litharge of Silver, the darker by that of Litharge of Gold; though neither of 
 
 them contains any portion of thofe metals (/). All the calces and fcoriae of 
 
 Lead vitrify moreeafily than thofe of any other metal : Expofed to a mode- 
 rately ftrong fire, they quickly run into a tranfparent yellow glafs. This 
 glafs, in fufion, powerfully diffolves and vitrifies the more refradlory metallic 
 calces and earths; and unlefs faturated with thefe kinds of additions, corrodes 
 and finks through the common crucibles ( m ). 
 
 Purification of If Gold or Silver be mixed with Lead, and expofed to the fire, the Lead 
 
 Gold and Sil- f cor ifies, as it would by itfelf, and arifes to the furface, fo as to be raked off 
 
 ver by Lead.- n ^ f orm Q] a )' s or Litharge ; at the fame time carrying with it any im- 
 perfect metal that the Gold or Silver had been mixed with, but leaving thofe 
 perfect metals themfelves unhurt. Hence Gold and Silver are purified by 
 means of Lead from admixtures of the bafer metals ; and hence Lead is called 
 by the chemifts, balneum foils & luna^ lavacrum regis & regin<e, fapo metal - 
 lorum , &c.— -The Litharge met with in the fhopS is produced in thofe works 
 where Gold and Silver are thus purified ; and contains the heterogeneous me- 
 tals which the Gold or Silver had been mixed with. 
 
 If 
 
 ( k ) Minium .] Minium is commonly pre- 
 pared from Lead calcined into a greyifh 
 powder by keeping it melted over the fire. 
 This powder, ground in mills, is further 
 calcined, in a reverberatory furnace, under 
 a low arch, and frequently ftirred with an 
 Iron rake, to prevent its melting and run- 
 ning into clots, and to expofe a frefh fur- 
 face to the aCtion of the air and flame. The 
 calcination lafts two or three days. The 
 Increafe of weight is faid to amount to one 
 fourth the weight of the Lead ; and the 
 Lead recovered from the Minium to be one 
 twentieth lefs than the original weight of 
 the metal. If the Minium be further cal- 
 cined, the increafe is no more ; but the 
 quantity of Lead recoverable proves lefs in 
 proportion to the vehemence and continu- 
 ance of the calcination. 
 
 (/) Litharge .] The deep coloured Litharge 
 is the moft perfect fort : The pale contains 
 a confiderable portion of Lead in its metal- 
 lic Hate, or uncalcined, and hence is never 
 to be employed for fuch operations as de- 
 
 mand a true calx or fcoria of Lead. Even 
 the highefl coloured Litharge is feldom free 
 from a little metallic Lead ; difcoverable, 
 and feparable, by melting the mafs in a 
 crucible, when the Lead fubfides to the 
 bottom. 
 
 (m) Glafs of Lead — diffolves earths , &c. in 
 fufion.'] Hence the ufe of Lead in vitrifica- 
 tions ; whether for procuring a fine tranf- 
 parent glafs, or for bringing refractory mi- 
 nerals, that participate of Gold or Silver, 
 into thin fufion, in order to the reparation 
 of thofe metals. The glafies made with it 
 are foft : And hence its unfitnefs as a bafis 
 for pafles and artificial gems, though it 
 anfwers extremely well in point of tranlpa- 
 rency, luftre, and beauty of the colours. 
 It is obfervable, that calces of Lead diflfolve 
 or vitrify fand veryeafily, but clay very dif- 
 ficultly ; hence crucibles, in whofe compo- 
 fition fand is an ingredient, are the fooneft 
 corroded by them : Calces of Iron, on the 
 contrary, render clay fufible, and fand re- 
 fractory. 
 
Metallic Bodies. 57 
 
 If Glafs of Lead be reduced into Lead, and the revived Lead fcorified again. Lead, 
 
 there commonly remains a fmall grain ol Silver : if the Glafs produced in t— — 
 
 this operation be again revived, another granule of Silver will be left upon P r0 * 
 afecond fcorification. There is a certain experiment, in which, by gradually 10m 
 taking away from the mercurial earth and adding to the inflammable and vi- 
 trefcible, greateft part of Lead, is [faid to be] convertible into Silver. 
 
 Lead mixed with Tin calcines fooner than by itfelf : One pound of Tin Calcination 
 
 quickly incinerates ten pounds of Lead (n). With Arfenic it runs into a hya-with Tin. 
 
 cinth coloured extremely fufible Glafs : But Sulphur, which promotes the Hyacinth 
 
 fufion of many of the metals, renders Lead remarkably difficult of fufion. 
 
 Lead expofed to the focus of Tlchirnhaus’s burning lens, firft frnokes, then,, en ' c ’ 
 
 v 03 7 . . Expofed to 3 
 
 looks burning-glak. 
 
 («) Lead with other metals .] Lead mingles 
 in fufion with all the metals except Iron ; 
 with which it refufes any degree of union, 
 fo long as the Lead preferves its metallic 
 form. On continuing the fire, the Lead, 
 fcorifying or calcining, abforbs the phlogi- 
 ftic principle of the Iron, and confequently 
 promotes the calcination of that metal : 
 both being at length reduced into calces, 
 the fufible faturnine calx diffolves the cha- 
 lybeate into an opake brown or blackifh 
 Glafs. 
 
 Copper does not unite with melted Lead 
 till the fire is raifed fo high, as to make the 
 Lead boil and fmoke, and of a bright red 
 heat : Pieces of Copper, now thrown in, 
 foon difiolve and difappear in the Lead : 
 The mixture when cold, is brittle, and its 
 fraCture of a granulated texture. The 
 union of thefe two metals is remarkably 
 flight : On expofing the mixture to a fire 
 no greater than that in which Lead melts, 
 the Lead almoft entirely runs off by itfelf ; 
 a feparation, of which we do not know 
 one other example. What little Lead is 
 retained in the pores of the Copper, may be 
 fcorified and melted out by a fire confider- 
 ably lefs than is lufficient to make Copper 
 flow. If any of the Copper is carried off 
 by the Lead, it fwims unmelted upon the 
 furface, fo as to be eafily fcummed off. 
 The coarfer forts of Lead, which owe their 
 brittlenefs and their granulated texture to an 
 admixture of Copper, throw up their Cop- 
 per in the fame manner on being melted by 
 a fmall heat, and thus become foft and 
 malleable. 
 
 Tin unites very eafily with Lead, into a 
 compound more fufible than Lead by itfelf, 
 and which is hence employed as a folder for 
 Lead. In point of malleability. Lead, of 
 
 all the metals, fuffers the lead from Tin; 
 becoming only a little more hard. The 
 metal, commonly made ufe of for organ- 
 pipes, is faid to be compofed of twelve 
 parts of Lead and one of Tin. 
 
 Gold and Silver are diffolved by melted 
 Lead in a flight red heat. They are both 
 rendered extremely brittle by the minuted 
 quantity of Lead ; though Lead is rendered 
 more duCtile by a fmall quantity of either 
 of them. 
 
 The affinities of Lead to different metals 
 are very remarkable. In cupellation, a 
 portion of it is retained by Gold ; but Silver 
 parts with it all. On the other hand, irk 
 its eliquation from Copper, if the Copper 
 contains either of the precious metals, the 
 Silver, will totally melt out with the Lead, 
 hut Gold will not. The attraction of Lead 
 to Copper, however flight, is greater than 
 that of Copper to Iron : A mixture of Cop- 
 per and Iron being boiled in melted Lead, 
 the Copper is imbibed by the Lead, and the 
 Iron thrown up to the top. Silver is in 
 like manner imbibed from Iron by Lead, 
 whilft Tin on the contrary is imbibed from 
 Lead by Iron. If two mixtures, one of 
 Lead and Tin, and another of Iron and 
 Silver, be melted together, the refult will 
 be two new combinations, one of the Tin 
 with the Iron on the top, the other of the 
 Lead with the Silver at the bottom : How 
 carefully foever the matter be ftirred and 
 mixed in fufion, the two compounds, when 
 grown cold, are found diftinCt, fo as to be 
 readily partdd by a blow. The affinities or 
 attractions Of metals to one another are no 
 where more confpicuous, nor the reparati- 
 ons depending upon them more perfect, 
 than in thefe examples. 
 
 I 
 
58 Metallic Bodies, 
 
 Lead, looks like melted Refin, and at length changes into a fort, yellowifh, greenifh, 
 v— — v — 1 and reddifh Glafs. 
 
 Solution in Lead diffolves in the nitrous Acid into a yellow liquor: The folution, irv- 
 the nitrous fpi gated, explodes or fulminates in the fire (0). The marine acid, added to 
 -aad. the folution, precipitates the Lead in the fame manner as it does Silver: And 
 
 --—the Precipitate, like the combination of the lame Acid with that metal, has, 
 when melted, fome degree of flexibility and tranfparency, fomewhat refem- 
 Cauftic fpint bling horn; whence its name Saturnus Corneas. Ir Lead or Minium be mixed 
 hom Sul Am- w j £ h s a l Ammoniac and expofed to the fire, the volatile alcali of the Salt is 
 extricated, and its acid abforbed by the Lead : The fpirit which diftills on 
 this occafion, like that prepared by Quicklime, is extremely volatile and cau- 
 ilic, and yields no concrete Salt : Its quantity is but fmall. 
 
 Geruffe, Lead expofed for fome time to the fleam of Vinegar or other vegetable 
 
 acids, is gradually corroded into a white calx, which is the Ceruffe or white 
 Lead of the fhops. The bed fort of Cerufife is in large thick flakes : The pow- 
 der forts are commonly adulterated with an admixture of Chalk or whiting. 
 The gre-atell quantities are made at Venice, Amflerdam, and in England. 
 
 Vegetable 
 
 (0) Mcnjirua of Lead , ] Proof Aqua fortis, 
 lowered with an equal quantity of water, 
 diffolves about half its weight of Lead. On 
 diluting the folution with a large quantity 
 of water, it' turns milky, and depofites the 
 metal. The folution (hoots, upon exhal- 
 ing a part of the menftruum, into fmall 
 pyramidal cryftals with fquare bafes, of an 
 auflere fweet tafle. 
 
 In the Memoirs of the French Academy 
 for the year 1733, there is a particular ac- 
 count of an experiment, in which Mercury 
 is faid to have been extradled from Lead 
 by diffolving it in the nitrous acid: Dur- 
 ing the diffolution, there fell a Precipitate, 
 which is plainly proved to be Mercury, 
 and which is looked upon as one of the 
 conftituent principles of the Lead, fepa- 
 rated by this fimple procefs. Probably 
 Aqua fortis made ufe of in this experiment 
 had been impregnated with Quickfilver : 
 In fuch cafe the Mercury precipitates in 
 proportion as the Lead difiolves ; but pure 
 Lead, diffolved in pure Aqua fords, gives 
 no fuch Precipitate. 
 
 ^Spirit of common Salt, concentrated or 
 diluted, has little or no effect upon Lead by 
 moderate digeflion. On raifing the fire, fo 
 as to make the liquor boil and diftill, the 
 Lead retains a portion of the acid, and 
 is corroded into a faline mafs, foluble, by 
 a repetition of the procefs, into a limpid li- 
 quor. When Lead is precipitated from 
 
 Aqua fortis by Sea-falt or its acid, an addi- 
 tion of A.qua regia rediffolves the calx, and 
 Sea-falt no longer occafions any precipita- 
 tion. 
 
 Oil of Vitriol, affifted by a boiling heat, 
 corrodes about half its weight of Lead into 
 a faline mafs. This acid, added to foluti- 
 ons of Lead made in either of the others, 
 imbibes the metal from them, and forms 
 with it an indifToluble concrete which falls 
 to the bottom. 
 
 Cauftic alcaline lixivia, boiled on plates 
 of Lead, diffolve a fmall portion, and cor- 
 rode a confiderable quantity : The folution 
 ftains hair black. Lead fufed with fixed 
 alcaline Salts is in part corroded into a dark 
 coloured fcoria, which partially diffolves in 
 water. 
 
 Expreffed Oils diffolve calces of Lead, by 
 boiling, in fuch large quantity as to be- 
 come thick or confiftent : Hence plafters, 
 cements for water-works, paint for preferv- 
 ing nets, &c. 
 
 Acids have a greater affinity with Lead 
 than Oils have. If the common plafter, 
 compoled of oil and Litharge, be boiled in 
 diftilled Vinegar, the Litharge will be dif- 
 folved, and the oil thrown up to the fur- 
 face. The oil thus recovered, proves fo- 
 luble, like efl’ential oils, in Spirit of Wine ; 
 a phoenomenon firft taken notice of by 
 Mr. Geoffroy. 
 
Metallic Bodies. 59 
 
 Vegetable acids diflolve Lead in its metallic ftate very difficultly and fpar- Lead.’ 
 sngly ; its calces more readily, though the quantity of thefe taken up is very — -7/ — — » 
 fmall. A dram of Litharge requires for its folution eight ounces of diflilled m 
 
 Vinegar, and a dram of Minium as much again : Out of a dram of Lead it- inegar * 
 felf, two pounds of Vinegar will hardly diffolve a fcruple. The folution is ofsaccharum 
 a fweet tafte •, and if duly evaporated, and fet in a warm place, that the re- Saturni. 
 maining moiffure may {lowly exhale, yields cryftals called from their fweet- 
 nefs, Saccharum Saturni , Sugar of Lead. 
 
 On diftiliing the Saccharum Saturni in a retort, there arifes an inflammable 
 fpirit, which is fuppofed to be Spirit of Wine refufcitated from the Vinegar j 
 though it has not the tafte of vinous fpirits : This is followed by a thin yel- 
 lowifh oil, and a thicker red one, efpecially if the Saccharum has been made 
 with undivided Vinegar. From twelve ounces cf the Sugar were obtained 
 three and a half of oily liquor: The refiduum weighed eight ounces and a 
 half, and yielded on redudtion feven and a half of Lead. Li'oavius and others 
 pretend that an inflammable fpirit may be obtained from a folution of Lead in 
 the vitriolic acid diluted with water, filtered and infpiflated : But though the 
 experiment was often with great care repeated and varied, no inflammable 
 liquor was produced. 
 
 Lead is employed for various mechanic ufes j as in thin ffieets for covering Ufes of Lead, 
 buildings, for pipes, ftatues, fhot and bullets, windows, for lecuring iron- 
 bars in hard ftones, for fundry kinds of large veflels for evaporation, &c. It 
 has been obferved that plants do not thrive fo well in leaden, as in earthen 
 and wooden veflels — —Its principal ufes in the chemical arts are, for promot- 
 ing the vitrification of earthy and ftony matters, in the making of Glafs, or 
 in the fmelting of ores, or in the glazing of earthen veflels t for the refining 
 of Gold and Silver ; for the eliquation of Silver from Copper j for forming 
 with oil, the bafis of varniffies and paints. 
 
 The effects of Lead on the human body are dangerous: Thofe who are ex- Medical hif- 
 pofed to its vapours in the fire, and even thofe who grind its calces, Minium, tor y Lead ’ 
 Cerufie and Litharge, for the painters, are fubjebt to violent gripes and con- 
 ftipations of the bowels, contractions of the limbs and other dilorders. Much 
 more hurtful is the internal ufe of Lead corroded or difl'olved by acids, as 
 Cerujje , Saccharum Saturni , the folution in Vinegar called Acetum Lithargyrii , 
 or the tindfure drawn from the Saccharum with Spirit of Wine commonly called 
 ( Iinftura Antiphthifica. The faturnine preparations are applied externally with 
 fafety, as coolers, repellents, and deficcatives : Its calces, difl'olved in oils, 
 form the bafis of moft of the officinal piafters. 
 
 Culinary veflels, lined with a mixture of Tin and Lead, which is the ufual 
 tinning, are apt to communicate to acid foods pernicious qualities, and require 
 to be ufed with great precaution — In Holland, and perhaps in other places, it has Method of 
 been cuftomary to correbt the more offenfive exprefled Oils, as that of rapefeed, dllc ° ve . nn S 
 fo as to fubftitute them to oil Olive or oil of Almonds, by impregnating them in ** 
 with Lead : This dangerous abufe may be difcovered, by mixing a little of the 
 fuipe&ed oil with a folution of Orpiment made in Lime-water: On fhaking 
 
 them together, and buffering them to reff, the oil, if it has any faturnine 
 taint, will appear of an orange-red colour-, if pure, of a pale yellowiflv 
 
 I 2 
 
 The 
 
6o Metallic Bodies. 
 
 Lead. The fame abufe has been extended alfo to acid wines, which diflolve fo much 
 
 k — '.Lead as to acquire a fweet tafte, and to become flow poifons. The Lead is 
 
 readily dilcovered in thefe likewife by the fame fulphureous folution ; which 
 changes the colour of wines impregnated with this metal to a brownifh red or 
 a blackfill ; Lead, whether diflolved or in its metallic form, being conftantly 
 flained by fulphureous liquors or vapours. 
 
 Lead is fometimes found in the earth native or in its metallic form, though 
 very rarely pure. Its common ores are nearly of the colour of Lead itfelf, and 
 appear compofed of cubes or parallelopipeds, fometimes large and regular, 
 fometimes irregular and fmall. There are Lead ores alfo of a white, greyifh, 
 or greenifh colour, and prifmatic figure*, but thefe are rarely met with, 
 (p) The ores of Silver, Copper, and other metals except Tin and Iron, have 
 often a Lead ore intermixed. The Lead is extracted by fufion in contact 
 with the fuel : The furnace being fufficiently heated with wood or charcoal, 
 the powdered ore is thrown in by degrees, and frefli fuel and ore occafionally 
 fupplied: The Lead, revived by the inflammable matter of the coals, runs 
 down into a bafon at the bottom of the furnace ; from whence it is laded out, 
 and caft in Iron moulds, into large mafles called pigs of Lead. All the com- 
 mon Lead ores contain fome Silver: The fteel-grained and fuch as are com- 
 pofed of fmall cubes, have generally more Silver than the compadt and large- 
 diced forts : The white and green fcarcely hold any. The Silver is extracted, 
 when its quantity is confiderable enough to bear the expence of extrading it, 
 by fcorifying the Lead upon a tefl: : The whole being kept in fufion on a 
 hearth made of bone-afli or other like materials, the Lead partly vitrifies and 
 finks into the hearth, and partly turns to Litharge which floats on the furface 
 and is raked or blown by bellows to one fide •> the Silver at length remaining by 
 
 itfelf. 
 
 (p) Lend Ores. ] Lead is exceeding rarely, If 
 ever, found native in the earth : The mafles, 
 which have been taken for native Lead, 
 appear, upon due examination, to be the 
 malleable leaden coloured ores of Silver — 
 The common Lead ores confifl: of Lead in 
 the ftate of a calx, blended with Sulphur : 
 Minium, Litharge, or other calces of Lead, 
 melted with Sulphur, form a compound 
 flmilar to them both in appearance and 
 quality. 
 
 The ores of Lead foften, in a moderate 
 red heat, into the confidence of a pafte, 
 but do not flow thin in a ftrong fire : If 
 Iron filings are mixed, the Iron abforbs the 
 Sulphur, and at the fame time revives the 
 Lead into its metallic form. This is one of 
 the mod commodious methods of fmelting 
 Lead ores, where the operation is performed 
 in veffels. Mr. Scheffer informs us, that 
 the Lead ores at Dal in Sweden, containing 
 from twenty to twenty-five ounces of Silver 
 on the hundred pounds, are fmelted by this 
 
 method, in crucibles, without any lofs of 
 the Silver ; and that the produce of Lead is 
 greater than that obtained by other means. 
 The aflayers generally calcine the ore, to 
 diffipate the Sulphur, and then melt it with 
 twice or thrice its weight of black flux ; 
 fufpeefing, that as the fcoria, when only 
 Iron is ufed, does not melt, a little of the 
 Lead may be retained in it. The yield of 
 Lead is from about one third to upwards of 
 two thirds of the weight of the ore ; accord- 
 ing as it is lefs or more free from fpar or 
 other heterogeneous earthy matters. 
 
 The white or greyifh, and the yellowifh 
 green ores are very rarely met with, and 
 their compofition is little known. They 
 are very ponderous, and very rich in metal : 
 On barely expofing them to the flame of a 
 candle, the Lead quickly and plentifully 
 melts out. They are fometimes cryftalline 
 and femitranfparent ; fometimes opake, and 
 little different in appearance from common 
 ftones. 
 
Metallic B o d i e, s, 6i 
 
 itfelf. Lead almoft .always contains fome portion of Copper; and hence the L e a d. 
 Silver obtained in this operation is fcarcely ever free from fome admixture of 
 that metal : If the pureft Silver be cupelled or tefted with Lead, it will gain 
 from the Lead a venereal taint ; a fmall proportion of Copper being defended 
 by the Silver from fcorifying along with the Lead (q). 
 
 II. COPPER. 
 
 , Venus y is a reddifli metal, eafily tarnifhing in a moift air, and Copper. 
 
 ng a green or a bluifh green ruft. It is the moft elaltic and fo- v-— 
 
 norous of all the metals, and the hardeft of all but Iron (r). It fpreads diffi- c!ia ’ 
 
 cultly under the hammer, but may be extended to a great degree ; drawn into 
 
 fine wire, and beat into thin leaves. Its fpecific gravity is near nine times 
 greater than that of water. 
 
 It requires for its fufion a ftrong white heat; greater than that in which Fufion, 
 
 Gold and Silver melt, though not lo great as that which is requifite for the 
 fufion of Iron [s). When melted, it is remarkably impatient of moifture : 
 
 The contaft of a little water occafions the melted Copper to be thrown about 
 with violence, to the great danger of the by-ftanders. It may neverthelefs be 
 
 granulated. 
 
 £OPPER 
 
 contradli 
 
 ( q ) Lead contains, &c.] Almoft all the com- 
 mon forts of Lead contain a portion of Sil- 
 ver, too inconfiderable to he extracted to 
 any advantage, but large enough to deferve 
 attention in the nicer chemical experiments. 
 In aflaying particulaily, where Lead is often 
 employed in eight, ten, twelve, or more 
 times the quantity of the ore or metallic 
 mixt to be examined, its purity from the 
 precious metals is of primary confequence ; 
 left we afcribe to the ore, the Silver fur- 
 nifhed by the fuperadded Lead. For the 
 greater certainty in this point, the Lead is 
 aflayed feparately : Thus, when a Silver 
 ore is to be fcorified by Lead, an equal 
 quantity of the fame Lead is at the fame 
 time fcorified by itfelf ; and the weight of 
 the button of Silver, left by the Lead, de- 
 ducted from that left by the ore and Lead. 
 
 Lead, revived from perfeCt Litharge, is 
 pure from the precious metals ; thefe me- 
 tals not being convertible with it into that 
 form. Litharge diftolves in Aqua fortis, 
 and is precipitated by oil of Vitriol; and 
 in thefe properties differs from all other me- 
 tallic calces. Hence by edulcorating the 
 Precipitate with frefh parcels of boiling 
 water, and reviving it with inflammable 
 fluxes, we obtain Lead perfectly pure from 
 all other known bodies. 
 
 (r) Copper— hardy &c,] Copper in fome 
 
 of its ftates Is as difficultly extended under 
 the hammer as Iron, but proves fofter to 
 the file ; and is never found hard enough to 
 ftrike a fpark with Flint or other ftones ; 
 whence its ufe for chifels, hammers, hoops, 
 &c. in the gun-powder works. Broke, by 
 often bending backwards and forwards, it 
 appears internally, of a dull red colour 
 without any confiderable brightnefs, and of 
 a fine granulated texture ; not ill refembling, 
 as Cramer obferves, fome kinds of earthen 
 ware. The fpecific gravity of the fineft 
 Copper I have been able to procure, turned 
 out to that of water as 8,830 to 1,000. 
 
 (s) Copper in the fire. ] Copper continues 
 malleable when heated red, and in this 
 ftate extends more eafily than when cold. 
 In this refpeCf it agrees with Iron ; but it 
 wants that valuable quality of Iron, by 
 which two pieces cohere when heated, fo as 
 to he welded or joined into one. When in 
 fufion, it appears on the furface of a bluifh— 
 green colour, nearly like that of melted 
 Gold. Kept in fufion for a length of time, 
 it becomes gradually more and more brittle, 
 but does not fcorify confiderably, nor lofe 
 much of its weight. It is much lefs de- 
 ftrudtible than any of the other imperfedt 
 metals, and is very difficultly fubdued even 
 by Lead or Bifmuth. 
 
 5 
 
6 2 
 
 •M -f, tallic Bodies. 
 
 Copper. 
 
 t - 
 
 Calcination. 
 
 Vitrification. 
 
 Solubility in 
 different li- 
 quors. 
 
 Phcenomena 
 in treating it 
 with different 
 acids. 
 
 granulated, like other metals, by cautioufly pouring a very little at a time into 
 
 water (/). 
 
 Kept in a heat below fufion, it contratSts on the furfacethin powdery (cales, 
 which, if rubbed off, are fucceeded by frefh ones, till the whole quantity of 
 the metal is thus (lowly changed into a dark reddifh fcoria or calx. This does 
 not melt in the greateft degree of fire that our furnaces are capable of giving ; 
 but in the concentrated folar heat, it runs eafily into a deep red and almoft 
 opake Glafs. A flaming fire, and a ftrong draught of air over the furface of 
 the metal, promote its calcination : The flame being tinged of a green, bluifh, 
 or rainbow colours, is a mark that the Copper burns. 
 
 Copper diffolves in every acid, in alcalies both fixed and volatile, in neutral 
 faline liquors, and in oils •, and when diffolved, exhibits fine blue, green, or 
 bluifh-green colours, by which this metal is readily diltinguifhed however 
 mixed or difguifed with other fubftances ( u .) Even pure water, fuffered to 
 ftand long in copper-veffels, extrabls fo much as to gain a coppery tafte : It 
 is obfervable, that water becomes more impregnated with the taffe on (landing 
 in the cold, than if boiled in the veffel for a longer time(x). 
 
 The nitrous acid diffolves Copper the mod readily and plentifully : The 
 folution is of a green colour. 
 
 The marine acid a6ls more languidly (jy) : The folution made in this acid 
 yields on being infpiffated, a greenifli mafs, which readily diffolves in water, 
 deliquiates in the air, gives a green tinflure to rectified Spirit of Wine, melts 
 in a lrnall heat, takes fire from a candle, and burns with a blue flame. The 
 
 marine 
 
 ( t ) Granulation .] Copper is faid to be gra- 
 nulated in the brafs-works atBriftol, with- 
 out explofion or danger, by letting it fall, 
 in little drops, into a large ciftern of cold 
 water covered with a brafs-plate : In the 
 middle of the plate is an aperture, in 
 which is fecured, with Sturbridge clay, a 
 fmall veffel, whofe capacity is not above a 
 fpoonful, perforated with a number of mi- 
 nute holes, through which the melted Cop- 
 per paffes. A dream of cold water is kept 
 constantly running through the ciftern : If 
 fuffered to grow hot, the Copper falls li- 
 quid to the bottom, and runs into plates. 
 
 (a) Diflinguijhed by its colour in folution .] 
 The colour of Copper is mod confpicuous 
 with volatile alcaline fpirits. Solutions 
 made in acids, when confiderably diluted, 
 have little colour: The addition of volatile 
 fpirits to the almoft colourlefs liquor renders 
 it inftantly of a deep blue. The hundredth 
 part of a grain of Copper, diffolved in a 
 pint of liquor, ftrikes a fenfible blue with 
 volatile alcalies. 
 
 (at) Corroded more by cold than by boiling 
 
 water. ] The cafe feems to be the fame in 
 regard to the mild vegetable acids. The 
 confectioners prepare the molt acid fyrups, 
 even thofe of Orange and Lemon-juice, by 
 boiling in clean copper veffels, without the 
 preparations receiving any ill tafte from the 
 metal; whereas either the juices themfelves, 
 or the fyrups made from them, if kept cold 
 in copper veffels, foon become impregnated 
 with a difagreeable tafte, and with the per- 
 nicious qualities of the Copper. 
 
 (y) Solution in the marine acid.] This folu- 
 tion, if made without heat, appears at firft 
 brown, but on (landing for fome time, de- 
 pofites a white fediment, and becomes 
 green : On adding frefh Copper, it turns 
 brown again, and now recovers its green- 
 nefs more (lowly than at firft. The white 
 fediment is not, as fome fuppofe, a part of 
 the metal deprived of its colouring principle: 
 On being barely melted, it proves pure and 
 perfedl Copper, of the fame red colour as at 
 firft Copper, calcined by fire, commu- 
 
 nicates to this acid not a green but a reddifh 
 tindlure. 
 
Metallic Bodies, 63 
 
 marine acid forfakes Mercury to unite with Copper : On expofing to the fire aCopptR. 
 
 mixture of Copper and Mercury-fublimate, the acid of the Sublimate forms ' 
 
 with the Copper a fufible inflammable concrete fimilar to the foregoing, whilft 
 the Mercury, difengaged, difiils in its running form. 
 
 The vitriolic acid does noteafily diffolve Copper unlefs highly concentrated 
 and affiGed by a confiderable heat : The folution is of a blue colour, and on 
 
 evaporating a part of the humidity, fhoots into elegant blue cryGals of a 
 rhomboidai figure; thefe are the blue Vitriol of the fhops. The folution is 
 moft commodioufly obtained by drawing over the oil of Vitriol from the 
 Copper, and elixating the refiduum with water ; then returning the diftilled 
 fpirit upon the undiffolved Copper, and repeating the abftradtion : Or by Gra- 
 tifying the Copper with Sulphur, in a crucible, and calcining or cementing 
 them together ; the Copper will abforb the acid of the Sulphur, fo as to be- 
 come in part loluble in water, and yield the fame cryGals as if the metal had 
 been boiled directly in the vitriolic acid. 
 
 Volatile alcalies, added to the folutions made in acids, oecafion at firft fome 
 precipitation, but prefentfy rediffolve what they had thrown down, and 
 change the colour, from a green or a pale blue, to a deep and lovely blue : 
 
 If the liquor is expofed for a time to the air, the volatile alcali efcapes, and 
 the colour which proceeded from it difappears. Volatile alcalies extract a 
 blue • tincture alfo from filings of the metal, without the intervention of any 
 acid (z). 
 
 Vegetable adds diflfolve Copper llowly, but in confiderable quantity r The y er d e o- r isj 
 folution fhoots into bluifh green cryftals fimilar to the Verdegris, arugo or 
 nitride eeris , of the fhops. This preparation is made in large quantity in 
 France, particularly about Montpelier, by Gratifying copper-plates with the 
 hufks of grapes remaining after the juice has been preffed out : Thefe foon be- 
 come acid, and corrode the Copper. 
 
 Verdegris fhould be cholen in cakes, not moiG or undtuous, but dry, com- 
 padt and of an uniform texture, of a lively green colour throughout, as free as 
 poGible from white or black fpecks, and feeds or Gaiks of the grape. It is 
 purified by folution in difiilled Vinegar, and cryGallization ; and then called, 
 improperly, diftilled Verdegris or flowers of Copper : The Dutch, who prepare 
 thefe cryfials in large quantity, after duly evaporating the folution, fet it to 
 fhoot, not as is cultomary in a cold, but in a warm place, as pradtifed for 
 making Sugar-candy. If rectified Spirit of Wine be added to the folution, or 
 if volatile alcalies be added to a folution of Copper and Spirit of Wine to this 
 
 mixture, 
 
 (z) Volatile alcalies. ] The blue mixture of ed with fats or other inflammable matters, 
 folution of Copper in Aqua fortis with vola- tinges their flame green, leaving a red calx 
 tile fpirits, yields fapphire coloured cryftals, of Copper folubie in volatile fpirits again as 
 
 which difiolve in Spirit of Wine,, and kn- at firft Boyle obferves that volatile fpi- 
 
 part their colour to it. If, inftead of cry- rits gain no tinge from Copper in vacuo : 
 
 Utilization, the liquor be totally evaporated ; Whether it is. the diftolution of the metal,, 
 the remaining dry matter, explodes in a or only the colour, that does not fucceed 
 moderate heat, like Aurum Fulminans. without air, has not been fully determined™ 
 
 The folution made in volatile alcalies, with- Oil of Vitriol added to the blue folutions, 
 out the intervention of any acid, yields on deftroys their colour : A frefh addition of 
 evaporation a blue faline mafs, which, mix- volatile Alcali recovers it again. 
 
64 
 
 Copper. 
 
 y -J 
 
 Divers expe- 
 riments on 
 Verdegris. 
 
 Metallic Bodies. 
 
 mixture, fmall blue cryftals will be immediately formed : Thefe are called by 
 fome antepileptic cryftals of Copper. 
 
 Highly rectified Spirit of Wine, digefted on half an ounce or twelve fcruples 
 of powdered Verdegris, diffolved three fcruples and a half ; ordinary rectified 
 Spirit, four fcruples ; common Malt Spirits, four and a half; and French 
 Brandy, feven and a half. Water diffolved, out of the fame quantity, five 
 fcruples : Common Wine Vinegar diffolved all but fifteen grains ; and diftil- 
 led Vinegar, all but ten grains (a). The whole quantity of Verdegris diffolved 
 in either kind of Vinegar, could not be recovered again in a cryftalline form : 
 From the common Vinegar, only two fcruples and five grains cryftallized, 
 and from the diftilled Vinegar three fcruples : The refiduum, in the firtt cafe 
 continued foftifb, in the latter dry. With French Brandy, there was no cry- 
 ftallization at all ; the whole that the fpirit had taken up, remaining uniformly 
 mixed, into the confidence of an extradt. 
 
 Verdegris diftilled in a retort, yields a concentrated acetous acid. Mr. Serane 
 relates, that from fixteen ounces of cryftallized Verdegris, he obtained three 
 ounces of phlegm, and afterwards fix ounces of ftrong fpirit; that the brown 
 powdery refiduum weighed five ounces and a half, and yielded, on fufion with 
 Borax, three ounces and fix drams of Copper. Lancifi mentions alio this ex- 
 periment, and feems to have borrowed it from Serane, the quantities being 
 exadtly the fame, except that only the drams of Copper are put down, the 
 ounces being by miftake omitted. I repeated the procefs, with the fame quan- 
 tity of Verdegris, and gained four ounces of phlegm, two ounces of fpirit of 
 moderate ftrength, three ounces and fix drams of ftrong fpirit, and fix ounces 
 two drams of refiduum. 
 
 The fpirit thus obtained is no other than the concentrated acid of Vinegar : 
 Zwelffer prepares a fpirit which is faid to be different. Cryftallized Verdegris 
 is reduced into grofs powder, put into a glafs retort with fo much highly redti- 
 fied Spirit of Wine as will cover it to the height of three or four fingers, the 
 vinous fpirit drawn off, and a frefh parcel returned two or three times: The 
 
 remaining Verdegris is then diftilled in a coated retort in an open fire, and the 
 acid fpirit which arifes, redtified by a fecond diftillation in a frefh retort. 
 Boerhaave relates, that this fpirit lofes its acidity, in the fame manner as other 
 acids, when combined with alcalies or abforbents, and that the pure acid is 
 never to be recovered again from thofe admixtures. Stahl on the other hand 
 confirms Zwelfter’s account, that this fpirit differs from the common acetous 
 acid in being recoverable from abforbent earths, as ftrong as at firft ; and 
 this repeatedly for any number of times. My experiments have not as yet 
 been carried far enough to determine this point : But it appears probable, that 
 Boerhaave, inftead of Zwelffer’s fpirit, employed common fpirit of Verdegris. 
 From tour ounces of dried cryftals of Verdegris I abftradted two parcels of 
 highly redtified Spirit of Wine, and found that the Verdegris had then loft fix 
 drams of its weight : Being now diftilled in an open fire gradually increafed, 
 
 it 
 
 (a) Refiduum of Verdegris .] The matter 
 which diftilled V inegar leaves undifl'olved, 
 <on being mixed with fome Borax and Lin- 
 ieed-oil, and fluxed in a crucible, yields a 
 
 brittle metallic fubftance, of a whitifh co- 
 lour not unlike bell-metal. What this 
 metal really is, has not hitherto been exa- 
 mined. 
 
Metallic Bodies. 
 
 6 S 
 
 it yielded one ounce, five drams and two fcruples of fpirit : The refiduum C o p pe r. 
 weighed half an ounce and one fcruple, and looked likeCoIcothar. The liquor 
 which came over about the middle of the diftillation, had a very volatile 
 penetrating lfnell ; and the ftronger fpirit fumed at times like the fmoking 
 mineral fpirits. 
 
 Quickhlver in its pure ftate amalgamates very difficultly with Copper, but Amalgams* 
 unites with it more eafily if divided by certain admixtures. If Mercury and tl0n * 
 Verdegris be triturated together, with common Salt, Vinegar and water, the 
 Copper in the Verdegris will be imbibed by the Mercury, and form with it, 
 as Boyle obferves, a curious amalgam, at hrftfoft fo as to receive any impref- 
 fion, and which, on handing, grows hard like brittle metals. Brals leaf like- 
 wife gives out its Copper to Mercury, the other ingredient of the Brafs fepa- 
 rating in the form of powder (l>). 
 
 Copper is the bafis of fundry compound metals for mechanic ufes ; as Brafs, Compound 
 Princes-metal, Bell-metal, Bath-metal, white Copper, Cfr. Brafs is prepared ™ etals Wltli 
 from Copper and Calamine, with the addition of powdered Charcoal, cemented ^°^ per * 
 together, and at length brought into fufion : Sixty-four pounds of Copper 
 commonly imbibe in this procefs twenty- fix pounds from the Calamine, and 
 yield ninety of Brafs : The paler the Brafs, the more of the Calamine it holds. 
 
 This metal, notwithflanding its large admixture of a brittle metallic body, con- 
 tinues hill remarkably cludtile : It is drawn into the fineft wire, for mufical 
 inftruments, &c.~ and beat into leaves in imitation of gold-leaf. The metallic 
 part of the Calamine, which here unites with the Copper, appears to be Zinc: 
 
 Hence Brafs, expofed to the fire, flames like Zinc itrfelf, and lofing by degrees 
 
 that volatile ingredient, becomes Copper again (c). Princes-metal is made by Princes-me- 
 
 melting Zinc in fubftance with Copper : And all the yellow compound metals, tal. 
 
 prepared 
 
 [b] Amalgam, of Copper.'] I have like wife 
 obtained amalgams of Copper, by grinding 
 Quickfilver, in an iron mortar, with a fa- 
 turated folution of the metal in Aqua fortis ; 
 as alfo with the muddy fubftance procured 
 in the polifhing of copper-plates; and by 
 cautioutly pouring a frnall quantity of 
 melted Copper, in a flender fcream, through 
 a perforated iron plate, into a large portion 
 of Quickfilver made almoft boiling hot. 
 The Copper, recovered from the amalgams, 
 retained its original rednefs ; and difcovered 
 no tendency to the yellow colour which 
 Homberg reports that this metal acquires 
 on being amalgamated and freed from the 
 Mercury. Even when Brafs is ufed for 
 making the amalgam, the recovered metal 
 is perfeft red Copper; the ingredient from 
 which the Brafs received its yellownefs be- 
 ing, as above obferved, feparated in the 
 amalgamation. 
 
 (r) Brafs.] The proportion of Calamine, 
 
 and the increafe which the Copper receives 
 from it, are different at different works : 
 Hence the deeper or paler colour of Brafs, 
 I have obferved, in a large fet of experi- 
 ments on this fubjeA; that a little of the 
 Calamine, (that is, of the Zinc contained: 
 in Calamine,) dilutes the colour of the 
 Copper, and renders it pale ; that when 
 the Copper has imbibed about one twelfth 
 its own weight, the colour inclines to 
 yellow ; that the yellownefs increafes more 
 and more till the proportion comes almoft 
 to one half; that on further augmenting 
 the Calamine, the Brafs becomes paler and: 
 paler, and at laft white. The crucibles,, 
 in which the fufion is performed in the large 
 works, are commonly tinged by the matter 
 of a deep blue colour. 
 
 Brafs is fomewhat lighter, harder, and 
 more fonorous, than pure Copper. It melts 
 more eafily, and does not fconfy fo foon 
 in a moderate red heat; and hence proves 
 more convenient for fundry forts of vefi'els 
 K and! 
 
66 
 
 Copper. 
 
 Bell metal. 
 
 White Cop 
 Pei'- 
 
 U'fe in paint' 
 i»g : &c. 
 
 Metallic Bodies. 
 
 prepared in imitation of Gold, are no other than mixtures of Copper with dif- 
 ferent proportions of that femi- metal taken either in its pure ftate, or in its 
 natural ore Calamine ; with an addition fometimes of iron filings, i£c. Zinc 
 itfelf unites moft eafily with the Copper, but Calamine makes the moft duftile 
 compound, and gives the yellowed: colour. Bell-metal is a mixture of Cop- 
 per and Tin : Though both thefe metals are malleable fingly, the compound 
 proves quite brittle (d). White Copper is prepared with Arfenic : Equal parts 
 of Arfenic and Nitre, pulverized and mixed together, are injefted into a red- 
 hot crucible, and kept in a moderate fire, till they fubfide and flow like wax : 
 One part of this mixture is injected upon four parts of melted Copper, and the 
 metal, asfoonasthey appear thoroughly united together, immediately poured 
 out. The Copper thus whitened is commonly melted with a confiderable 
 proportion of Silver, by which its colour is both improved and rendered more 
 permanent (e). 
 
 Sundry preparations of Copper are employed in painting, ftaining, and for 
 colouring Glafs and enamels (/). Verdegris makes a fine green both in oil 
 
 and 
 
 bare apportion of part. Of thofe that have 
 been tried, fome exceeded the mean, but 
 the greater number fell fhort of it : Copper 
 and Tin were the only ones, that formed 
 a compound heavier than the heavieft of 
 the metals feparately. 
 
 From thefe obfervations it is obvious, that 
 Archimedes’s propofition, and the tables 
 calculated on that principle in the Common- 
 taria Petropolitana, Sec. for determining the 
 proportion of two metals in a given mixt by 
 hydroftatical experiments, are lefs to be de- 
 pended on than has hitherto been fup- 
 pofed. 
 
 (e) White Copper .] The white Copper of 
 China and Japan appears to be no other 
 than a mixture of Copper and Arfenic. 
 Geoffroy, relates, that on repeated fufions, 
 it exhaled arfenical fumes, and became red 
 Copper ; lofing, with its whitenefs, one fe- 
 venth of its weight — Copper is faid to be 
 whitened alfo by cementation with the 
 afhes of Tartar imperfectly burnt : I have 
 frequently cemented it with thefe, for dif- 
 ferent lengths of time ; without being able 
 to perceive the leaft alteration in the colour 
 of the Copper. 
 
 ( f) Staining , coloured Glafs , &c.] Solution 
 of Copper in Aqua fortis lfains Marble and 
 fome other ftones of a green colour : Pre- 
 cipitated with Chalk or whiting, it yields 
 the green and blue verditer of the painters. 
 A folution made in volatile fpirits ftains 
 
 and utenfils. It is duClile only whilft cold: 
 Heated a little, it cracks, ignited it falls in 
 pieces under the hammer. This imperfec- 
 tion it receives from the Zinc ; pure Cop- 
 per being malleable when hot as well as 
 when cold. 
 
 (d) Copper with Tin.] Copper is diffolved 
 by melted Tin, eafily and intimately ; far 
 more fo than by Lead. A fmall portion of 
 Tin renders Copper dull coloured, hard, 
 and brittle : Bell-metal is compofed of about 
 ten parts of Copper to one of Tin, with 
 the addition, commonly, of a little Brafs or 
 Zinc. A fmall portion of Copper, on the 
 other hand, improves the colour and con- 
 fidence of Tin, without much injuring its 
 dudbility : Pewter is fometimes made from 
 one part of Copper and twenty or more of 
 Tin. 
 
 Tt has long been obferved, that though 
 Tin is fpecifically much lighter than Cop- 
 per, yet the gravity of the compound, Bell- 
 metal, is greater than that of Copper itfelf. 
 I found the fame augmentation of gravity 
 alfo where the lighter metal was in greater 
 proportion : A mixture even of one part of 
 Tin with two of Copper turned out fpeci- 
 fically heavier than pure Copper. 
 
 From fome experiments on other metals, 
 which this remarkable phcenomenon gave 
 occafion to, it appeared that few metallic 
 mixtures anfwer to the mean gravity of the 
 ingredients, or fuch as would refult from a 
 
Metallic Bodies. 67 
 
 and in water colours, inclining more or lefs to bluifh : A folution of it inCoppE r. 
 Aqua fords, infpiffated, tinges Glafs in fufion of the fame colour. In fome — v— * 
 
 parts of France, it is cuftomary to mix Verdegris with Plafter-of- Paris, which 
 by this means is faid to become firmer and more durable. It is employed alfo 
 in cements for heightening the colour of Gold : A mixture of Gold with one 
 third, or even with hall its weight of Silver is faid to acquire on cementation 
 with Verdegris, the colour of pure Gold : See Gold. 
 
 The medical ufeof Copper is entirely external : Verdegris, and blue Vitriol, Medical Hif- 
 . are employed as mild efcharotics, for cleanfing fiftulous ulcers, and other like pur- t0I 7* 
 pofes. Internally, all the preparations of this metal are extremely dangerous : 
 
 Examples are too frequent of fatal confequences from eating food that had re- 
 ceived a taint from copper- vefiels ; whether from the food itfelf being of an 
 acid nature fo as to corrode or diffolve a portion of the metal ; or from the 
 veflei having contracted a foluble rult or Verdegris by lying in the air : The 
 
 utmoft caution is therefore requifite in the ufe of copper-vefiels, and even of 
 Silver ones that are largely alloyed with Copper. I knew a perlon, who hav- 
 ing accidentally fwallowed a brafs fleeve- button, was feized with violent fymp- 
 toms, and died In mifery ; no medicines giving relief. I have known vehement 
 vomitings, and even convulfions, in children, from the unguentum agyptiacum , 
 whofe bafis is Verdegris, applied to ulcers in the mouth : When employed in 
 this intention, as it commonly is, the patient muft be well upon his guard 
 againlt any of it paffing down. 
 
 Copper is exceeding rarely found pure in the earth. Of its ores there is a Natural Hif- 
 great variety, intermixed with different ftony matters, generally abounding tory. 
 with Sulphur, fometimes containing a little Arfenic. Thefe ores are often of 
 beautiful colours, blue, red, green, yellow, variegated like the rainbow or 
 peacock’s tail, moft commonly green or blue : They are of all ores the moft 
 
 beautiful. The Lapis Lazuli, from which the precious blue pigment called 
 Ultramarine is prepared, is one of the ores of this metal. Some of them con- 
 tain no metal but Copper ; many have an admixture of others ; and there are 
 few ores of other metals without fome portion of Copper in them. Copper is 
 of all metals the mod difficultly obtained pure from the ore ; Sulphur adher- 
 ing to it fo ftrongly, as not to be expelled without long calcination. When 
 Copper and Iron are blended together in the ore, the Copper cannot by any 
 
 method 
 
 ivory and bones, macerated for fome time 
 in the liquor, of a blue colour, at firft fuf- 
 ficiently beautiful, but which tarnifhes in 
 the air, and becomes green. I know of no 
 method of obtaining by art a permanent 
 blue from Copper, but by vitrification. I 
 have prepared elegant deep blue glaffes by 
 melting common Glafs, or compofitions of 
 powdered Flint and fixed alcaline Salt, with 
 Verdegris, with blue Vitriol, and with an 
 amalgam of Copper ; fine green ones, with 
 
 K 
 
 green Verditer, with blue Verditer, with a 
 Precipitate of Copper made by fixed alca- 
 lies, and a Precipitate by Zinc; and a 
 reddifh Glafs, with calx or fcoria of Cop- 
 per made by fire alone : Even in this vitre- 
 ous ftate however, it feems as if a continu- 
 ance of fire had the fame effedf, in regard 
 to colour, as air has upon Copper in other 
 forms: Some cf the moft beautiful blue 
 glaffes, by continued fufion, changed to a 
 green, 
 
 2 
 
68 Metallic Bodies, 
 
 C o p p e r. method as yet known, be feparated to advantage : A rich Copper- mine, at 
 — / — — > Lauterberg in the Hartz foreit, lies on this account unworked. 
 
 There are ores of Copper in almoft all parts of the world ; in Spain, France, 
 England, Norway Saxony, Bohemia; but more particularly in Sweden, 
 Hungary, and Tranfylvania. Japan affords a fort of Copper, fuperior to any 
 met with in Europe. 
 
 Copper is found alfo in a vitriolic flare, diffolved in certain waters, as at 
 Neufol in Hungary : When Iron is put into the water, the diffolved Copper 
 feparates ; a proportionable quantity of the Iron being diffolved in its place. 
 The Copper, extricated from the liquor, adheres to the Iron, and covers its 
 furface with a bright cupreous coat : Some have been fo far impofed on, as to 
 imagine the Iron, by this means, actually tranfmuted into Copper. 
 
 III. IRON. 
 
 Iron. JRON, Mars , is a greyifh metal, foon tarnifhing in the air to a dufky 
 >_ j blackifh hue, and in no long time contradling a yellowifn or reddifh ruft. 
 
 Its general It is the molt fonorous of the metals except Copper ; the hardeft and moft: 
 charaders. e } a ftj c G f them all *, hence its excellence for mechanic inftruments : It is made 
 into tools, by which all the others are filed, drilled, and cut ; and is the only 
 one that flrikes fparks with Flint. It fpreads difficultly under the hammer, but 
 may be extended to a great degree, drawn into wire as flender as the fined: 
 hairs : It is more eafily malleable when ignited than when cold ; whilft fome 
 of the other metals, though dudtile when cold, become quite brittle by heat. 
 It is lighter, confiderably, than Copper ; and a little heavier than Tin. It is 
 the only metallic body, which attracts, or is attradled by, the magnet, one of 
 its own ores. 
 
 Ignefcibility, Iron grows red-hot much fooner than any other metal, and this not only 
 from the application of adlual fire, but likewife from flrong hammering, 
 Fufibility, friflion, or other mechanic violence. It neverthelefs melts the moft difficultly 
 of all the metals ; requiring, in its moft fufible ftates, an intenfe bright white 
 heat. When perfectly malleable, it is not fufible at all, without additions, or 
 the immediate contact of the burning fuel ; and when melted, it lofes its 
 malleability: All the common operations which communicate one of thefe 
 qualities, deprive it at the fame time of the other, as if fufibility and mallea- 
 bility were in this metal incompatible. 
 
 Calcination, Expofed to a white heat, infufficient for its fufion, it contracts a femivitreous 
 coat, which burfts at times, and flies oft'in fparkles : No other metallic body 
 exhibits any fuch appearance (g). On continuing the fire, it changes by de- 
 grees 
 
 (g) Iron , phenomena from fire.'] The con- 
 tail of cold liquors occafions Iron to fcale 
 in a fmall degree of heat : Hence its unfit- 
 nefs for boilers in fuch works as require 
 them to be emptied and charged again 
 whilft hot. 
 
 It does not tinge the flame of burning 
 
 matters bluifli or greenifh, like the other 
 imperfeil metals, but brightens and whitens 
 it : Hence the ufe of Iron filings in the 
 
 compofltions for fire-works, called white 
 fire. 
 
 Strongly heated, it appears covered on 
 the furface with a foft vitreous matter like 
 
 varnifh : 
 
Metallic 
 
 Bodies. 
 
 grees intQ a dark red calx, which does not melt in the mod vehement heat I r o n. 
 procurable in the furnace of the chemift, and which if brought into fulion y. 
 by additions, yields an opake black glafs. Glafs made from Iron, by Vitrification, 
 whatever means, is always black, unlefs the quantity of vitreous matter mixed 
 with it, be very large (Jo ) : The calces made by acids and by fire, are of vari- 
 ous fhades of yellow, brown, and red. 
 
 Iron 
 
 varnifh : In this ftate, pieces of it cohere, 
 and on being hammered together, weld or 
 unite, without difcovering a juncture. As 
 Iron is the only metal, which exhibits this 
 appearance in the fire, it is likewife the only 
 one capable of being welded. Thofe ope- 
 rations, which prevent the fuperficial fco- 
 rification, deprive it of this valuable pro- 
 perty ; which may be reftored again by fuf- 
 fering the Iron to refume its vitreous afpedl, 
 and in lome meafure, by the interpofition 
 of foreign vitrefcible matters ; whilft none 
 of the other metals will in any degree 
 unite even with its own fcoria. 
 
 Iron expands the leaf! of the metals by 
 heat. In the adt of fufion, inftead of con- 
 tinuing to expand, like the other metals, it 
 fhrinks ; and thus becomes fo much more 
 denfe, as to throw up fuch part as is un- 
 melted, to the furface ; whilft pieces of 
 Gold, Silver, Copper, Lead, Tin, put in 
 the refpeddive metals in fufion, fink freely 
 to the bottom. In its return to a confiftent 
 ftate, inftead of fhrinkinc like the other me- 
 tals, it expands ; fenfibly rifing in the vefiel 
 and affirming a convex furface, whilft the 
 others fubfide and appear concave. This 
 property of Iron, firft taken notice of by 
 Mr. Reaumur, excellently fits it for re- 
 ceiving impreffions from moulds : By the 
 increase of bulk, which the fluid metal ac- 
 quires in its congelation, it is forced into 
 the minuteft cavities, fo as to take the 
 figure far more perfectly than the other 
 metals which fhrihk. The workmen have 
 often obferved, that Iron, though poured 
 quite thick into the mould, has neverthelefs 
 received its impreflion in perfection ; and 
 have wondered to fee figures of caft Iron 
 larger than the mould, whilft thofe of other 
 metals are lefs. 
 
 Iron with other metallic bodies.'] Iron is dif- 
 folved by all the metals made fluid by fuf- 
 ficient heat, except Lead ; on which it 
 floats diftindt, as oil upon water : Gold, 
 of all metals, adts on it the moft power- 
 
 5 
 
 fully ; though, as Cramer obfcrves, if the 
 Iron contains any portion of Sulphur, it can 
 fcarcely be made to unite at all with Gold. 
 
 Among the femi-metallic bodies, it is 
 averfe to any union with Mercury : No 
 method has hitherto been difcovered of a- 
 malgamating Iron ; though Quickfilver, in 
 certain circumftances, feems in fome fmall 
 degree to adt upon it. A plate of tough 
 Iron, kept immerfed in Mercury for fome 
 days, becomes brittle: And I have often 
 obferved Mercury adhere to and coat the 
 ends of iron peftles ufed in triturating cer- 
 tain amalgams with faline liquors. 
 
 Next to Mercury, Zinc is the moft diffi- 
 cultly combined with it ; not from any na- 
 tural indifpofition to unite, but from the 
 Zinc being difficultly made to fuftain the 
 due degree of heat : The mixture is hard, 
 fomewhat malleable, of a white colour ap- 
 proaching to that of Silver. Regulus of 
 Antimony, as foon as it melts, begins to 
 adt on Iron, and dilTolves a confiderable 
 quantity : If the Regulus be ftirred, in fu- 
 fion with an iron rod, it will melt off a 
 part of the Iron. Arfenic likewife mingies 
 eafily with Iron, and difcovers a great at- 
 traction to it, forfaking all the other me- 
 tals to unite with this : It renders the Iron 
 white, very hard, and brittle. 
 
 (/') Iron with vitreous matters.] The co- 
 lours which Iron imparts to Glafs in fufion, 
 are various and inconftant. Vitrified with- 
 out addition, by the concentrated folar heat, 
 it is faid to be bluifh or purplifh : Scorified 
 in our furnaces, it appears of a back or dark 
 brown, and communicates the fame dufky 
 hue to three or four times its quantity of 
 colourlefs Glafs. Its feveral calces, fu/ed 
 with much larger proportions of vitreous 
 matters, impart different fnades of yellow, 
 reddifh, green and blue. Practical writers 
 in general fpeak of one preparation giving 
 one colour; and another, others. From 
 fuch experiments as I have made in this 
 
 view. 
 
7 ° 
 
 Iron. 
 
 Metallic Bodies. 
 
 Expofed to 
 a burning- 
 g'afs. 
 
 Solubility in 
 different li- 
 
 quors. 
 
 Prefervation 
 from ruff. 
 
 Solution in 
 Vitriolic acid 
 
 inflammable 
 vapour ; 
 
 Iron placed in the focus of Tfchirnhaus’s large burning-glafs, melts in an 
 inftant, and looks like a black Bitumen or Pitch : The French academicians 
 concluded from hence, that the inflammable principle of Iron was an actual 
 bituminous matter : But no experiment gives any juft foundation for this con- 
 jecture : The pretended Bitumen is no other than vitrified Iron ; and Iron cal- 
 cined or vitrified, that is deprived of its own phlogifton, is revived into Iron 
 again by any vegetable or animal coal, in the fame manner as the other 
 metals. 
 
 Iron diflfolves eaflly in all acids ; it is likewife fenfibly aCted upon by alca- 
 line and neutral liquors, and corroded even by thofe which have no perceptible 
 faline impregnation : Strongly heated, and quenched in water, it communi- 
 cates a manifeft take to the liquor: The filings expofed to the air, and occa- 
 fionally rnoifiened with water, foon change into ruH. Even the oils, with 
 which Iron utenfils are often rubbed to prevent their rufting, in fome meafure 
 contribute to promote that effeCt. Some employ, with better fuccefs, oil that 
 has been gently boiied for a time •, cautioufiy pouring into the oil, towards the 
 end of the boiling, fome melted Lead : The oil is by this means freed from 
 its watery phlegm, and from its acid principle, which are the caufe of its 
 promoting the corrofion of the metal. Animal fats are faid to anfwer Hill 
 better; thefe being void of the leaft degree of acidity. Homberg’s falve for 
 preferving Iron from ruft, communicated to the French academy, confifts of 
 two pounds of hog’s Lard, an ounce of Camphor, and as much black Lead 
 as will render the mixture of an iron colour: The Iron is to be heated, before 
 it is anointed with this compofition (z). 
 
 The vitriolic acid requires to be diluted with three or four times its quan- 
 tity of water, to enable it effectually to diffolve Iron. During the diffo- 
 lution, a ftrong fulphureous vapour arifes, which on the approach of a candle, 
 takes fire(i). The folution is of a grafs green colour: On Handing, ie 
 
 gradually 
 
 view, the colour feems to be influenced 
 more by the degree and continuance of the 
 fire, and other circumftances in the procefs, 
 than by the particular manner in which the 
 Iron is prepared. With the officinal flow- 
 ers of Steel I have made a yellow and a 
 .greenifh Glafs ; with the matter which re- 
 mains after the fublimation of the flowers, a 
 yellow, a green, and a blue : without be- 
 ing able to determine the particular circum- 
 ftances in which either of thefe colours 
 might with certainty be produced. One of 
 the bluiih green glan’es, on being melted a 
 fecond time, loft its bluifh caft, and be- 
 came of a deeper green than at firft : After 
 a third fufion, it looked green, yellow and 
 red in different parts of the mafs. With 
 the calx made by long reverberation, I 
 obtained a red but an ill-coloured Glafs; 
 not the lovely one which Kunckel promifes : 
 A piece of this Glafs kept long in fufion. 
 
 difcovered a tendency to bluenefs. 
 
 (/) Preferved from ruft.] Mr. Reaumur 
 has difcovered a compofition which appears 
 fuperior to all the foregoing. Exprefled 
 Oils, expofed to the air in flat fhailow vef- 
 fels fo as juft to cover the bottom, become 
 thick, without lofing their tranfparency, or 
 acquiring any brown or other colour, which 
 they always do when thickened by boiling. 
 The infpiffated Oil, fkilfully mixed with a 
 folution of Copal in Spirit of Wine, forms 
 an elegant hard varnifh. Polifhed Iron, 
 made a little hotter than the hand can bear, 
 and rubbed with a ftick of this varnifh, ap- 
 pears, as foon as cold, covered with a folid, 
 thin, tranfparent coat, without the leaft in- 
 jury to its colour or appearance^ 
 
 (, k ) Inflammable vapour.] This vapour is 
 permanent and elaftic, and feems to have a 
 
 great 
 
Metallic Bodies, 71 
 
 gradually depofites great part of the Iron in form of a yellow or reddilh calx Iron, 
 or ochre : Duly evaporated, it ihoots into rhomboidal cryftals, which are the u . -y *. . . j 
 
 green Vitriol, or fait of Steel, of the fhops— The calx precipitated from 
 
 this folutioruby fixed alcaline laics, is exceeding difficultly reducible into its 
 metallic ftate. 
 
 The nitrous acid undiluted, a£ts violently on Iron, corrodes it plentifully, In n j trou3 
 but diffolves little j and what has thus once been corroded, will not diffiolve acid: 
 in freffi acid. If the acid has been diluted at firil with water, it takes up a 
 considerable proportion, provided the metal be leifurely added. If the Solu- 
 tion is performed with extreme flownels, the colour will be green ; if other- 
 wife, of a dark red. It does not cryftallize ; and if infpififated to drynefs, de- 
 liquiates in the air. 
 
 The marine acid adts lefs vehemently on Iron than the nitrous, and does In the marine 
 not difiolve fo much. The Solution is of a faffron or gold yellow colour: It acid> 
 does not cryftallize ; and if infpifiated, leaves a greenifh Saline mafs, which 
 diffolves not only in water but likewife in Spirit of Wine, and runs in the air 
 into a yellow liquor : In distillation, a considerable portion of the Iron is vo- volatilized* 
 latilized (l). Ammoniacal Salts likewife, compofed of the marine acid and 
 volatile alcalies, elevate So much of this metal in Sublimation, as to receive 
 from it a deep orange colour. This preparation is kept in the Shops under 
 the name of fores martiales , Sal ammoniacum mar dale, or mars diaphoredcus : It 
 is commonly made from one part of clean filings of Iron, and two of Sal 
 Ammoniac, well mixed together, and Sublimed : A little urinous Spirit arifes 
 before the yellow flowers, and generally a little marine acid after them. The 
 refiduum, Set in a cellar, runs into a liquor Similar to that made with Spirit 
 of Salt diredtly ; called liquor mar halts, or liquamen marks. 
 
 Vegetable acids, even wines that are but Slightly acidulous, diffolve a con- With vegeca- 
 fiderable quantity of Iron into a reddilli liquor. The purer acids, as difiilledhle acids. 
 
 Vinegar, by proper management, cryftallize with it Fixt alcaline Lixivia Solution in 
 
 Seem to have little effecft upon Iron in its metallic State : But if a Solution ofalcalies. 
 
 Iron, made in the nitrous acid, be dropt into a Saturated lixivium, the Iron 
 remains permanently diffolved in the alcali : The liquor appears at firft of a 
 
 yellowifli red colour ; when loaded with the Iron, of a deep blood-red. Here 
 
 the 
 
 great analogy to the inflammable damps in 
 mines. It may be colledted and preferved 
 in bladders ; which being applied to the 
 mouth of the veflel, wherein the diflolution 
 is made, will Soon be filled and diftended 
 by it. After keeping for Several weeks, a 
 little of the vapour, forced out near a 
 candle, inftantly took flame as at firft. 
 
 (/) Iron volatilized by Spirit of Salt. J The 
 Spirit which diftils towards the end of the 
 procefs appears yellow: This is followed by 
 a yellowilh or deep reddilh Sublimate, which 
 gliftens like the Scales of fifties ; leaving be- 
 hind a fubftance which conlifts of thin glofly 
 plates like Talc. 
 
 Iron with other metallic folutions.} Iron pre- 
 cipitates from acids all metallic fubftances 
 except Zinc, and the newly discovered fe- 
 mimetals Regulus of Cobalt and Nickel-*- 
 By folutions of Copper in acids, the Iron is 
 ftained of a copper colour ; the Copper be- 
 ing extricated from its menftruum in its 
 metallic form, and adhering to the Surface 
 of the Iron. By folutions of Gold com- 
 bined with rectified Spirit of Wine, it is in 
 like manner covered with a golden coat : 
 The preparation of Gold, Said to anfwer 
 beft for this purpofe, is a Bindture drawn 
 from a mixture of Gold-leaf, Sea-ialt, and 
 Alum, melted together, or boiled in water 
 to drynefs. 
 
2 
 
 Iron. 
 
 Ufes in (cran- 
 ing and dy- 
 ing- 
 
 Tigments. 
 
 Metallic Bodies. 
 
 the acid ferves only as a medium of union betwixt the Iron and the Alcalr, 
 and after the union is once effected, has no Ihare in the continuance of it ; the 
 acid forming, with a part of the alcaline Salt a true Nitre, which may be fe- 
 
 parated from the martial folution by cryftallization Much has' been faid in 
 
 books, of preparations of Iron that fulminate in the fire : I have made numer- 
 ous trials for obtaining the Mars fulminans , without being ever able to fucceed. 
 
 Solutions of Iron made in acids give a yellow ftain to linen, &c. and 
 ftrike a black colour with galls and other vegetable aftringents {m). Thefe 
 are very valuable properties of Iron to the callico-printer, the ftainer of 
 leather, wood, (ffc. and the dyer. For linen and leather, the metal is com- 
 monly difloived in four whey or fmall-beer ; for dying, the Vitriol is made 
 ufe of, (fee Vitriol). This metal affords alfo, in its calces, red and yellow 
 pigments to the painter; and a fine blue in the preparation called, from the 
 place where it was firft difcovered, Berlin or Prufiian blue («) A flight fo- 
 
 lution of Vitriol has been employed by fome as an affay liquor for diftinguifh- 
 
 ing 
 
 pared by precipitating a folution of green 
 Vitriol and Alum with a Lixivium drawn 
 from fixt alcaline Salt that has been cal- 
 cined with animal coals. Commonly about 
 three parts of Alcali and two of dried ox 
 blood are calcined fo long as any flame ap- 
 pears, then thrown into boiling water, and 
 the {trained decodtion poured into a hot 
 mixture of folutions of four parts of Alum 
 and one or lefs of Vitriol. The liquor be- 
 comes inftantly thick or curdly, and looks 
 at firft of a greyifh colour, which changes 
 to a brown, and in a little time to a bluifh 
 green. The matter being well ftirred to- 
 gether, and mixed with a quantity of hard 
 lpring- water, a green precipitate fubfides : 
 Spirit of Salt poured upon the edulcorated 
 powder, diffolves a part, and leaves the reft 
 blue. 
 
 Mr. Geoffroy is the firft who has given 
 any plaufible theory of this procefs, or any" 
 rational means for improving it. He ob~ 
 ferves, that the Prufiian blue is no other 
 than the Iron of the Vitriol, revived by the 
 inflammable matter of the alcaline Lixi- 
 vium, and perhaps brightened by an admix- 
 ture of the white earth of the Alum ; that 
 the green colour proceeds from a part of 
 the yellow ferrugineous calx or ochre unre- 
 vived, mixing with the blue ; and that the 
 Spirit of Salt diffolves this ochre more rea- 
 dily than the blue part, though it will dif— 
 folve that alfo by long handing, or if ufed 
 in too large quantity. From thefe prin- 
 ciples he was led to increafe the quantity of 
 
 inflam- 
 
 (tn) Black with vegetable ajlringertts .] This 
 property of Iron affords a commodious me- 
 thod of diftinguifhing minute portions of it 
 in mineral waters or other liquors. A 
 fxngle grain of Vitriol of Iron, diffolved in a 
 gallon of water, inftantly difcovers itfelf, 
 on adding a little powdered Galls, by a 
 dufky blue colour. A more faturated folu- 
 tion of the Vitriol ffrikes with galls a deep 
 black colour; and this black mixture, di- 
 luted, appears blue like the former. If the 
 liquor is impregnated with a minute portion 
 ef alcaline Salt, fixed or volatile, inftead of 
 a blue or blackifh, a purplifn red tindlure is 
 produced : This is the colour which Chaly- 
 beate mineral waters ftrike with galls. 
 
 As it is only with vegetable aftringents, 
 that Chalybeate folutions ftrike a blue or a 
 black colour ; thefe liquors have been em- 
 ployed as a teft of aftringency in vegetable 
 fubftances. I have obferved, however, that 
 fome vegetables, manifeftly and powerfully 
 aftringent, do not exhibit this phcenome- 
 nonj their aftringency refiding in a prin- 
 ciple not diffoluble in watery liquors, and 
 not mifcible with the vitriolic folution. 
 The refmous aftringent, Peruvian bark, 
 mixed with folution of Vitriol, in fmall or 
 in large proportions, in the form of pow- 
 der, infufton, decodlion, extradl, vinous or 
 foirituous tindlure, gives not a blue or a 
 black, but a green colour, which with cer- 
 tain proportions is very deep and bright. 
 
 (?#) P ruffian blue.} Prufiian blue is pre- 
 
Metallic Bodies. 
 
 ing French brandies from common fpirits prepared in imitation of them-, 
 
 French brandy having ufually an aftringent impregnation from the oaken 
 cafks in which it has been kept, and hence {hiking a bluifh or black colour 
 with the Chalybeate folution ; whilft fpirits tinflured only with melaffes, burnt 
 fugar, &c. give no fuch colour. The principle, on which the blue colour de- 
 pends, (hews that it is no certain teft: All fpirits will exhibit it if impregnated 
 with aftringents ; and French brandies will not, without fuch impregnation. 
 
 Iron deflagrates with Nitre, and renders the Salt alcaline and cauflic (<?). It Treated with 
 readily unites with Sulphur; and when combined with it, like the other refrac- ^ ltr? > and 
 tory metals, proves much eafierof fufion than by itfelf. A mixture of Sulphur 
 andiron filings, moiflened with water and prefTed down clofe, in a few hours earthquakes, 
 
 fwefis 
 
 inflammable matter, that there might be 
 enough to revive the whole of the ferrugi- 
 neous ochre, and produce a blue colour at 
 once without the ufe of the acid fpirit : In 
 this he perfectly fucceeded, and found at 
 the fame time, that the colour might be 
 rendered of any degree of deepnefs or light- 
 nefs at pleafure. If the Alcali is calcined 
 with twice its weight of dried blood, and 
 the Lixivium, obtained from it, poured in- 
 to a folution of one part of Vitriol to fix of 
 Alum, the liquor acquires a very pale blue 
 colour, and depofites as pale a precipitate : 
 On adding more and more of a frefh folu- 
 tion of Vitriol, the colour becomes deeper 
 and deeper, almoft to blacknefs. He ima- 
 gines, with great probability, that the blue 
 Pigment thus prepared will prove more dur- 
 able in the air, mingle more perfectly with 
 other colours, and be lefs apt to injure the 
 iuftre of fuch as are mixed with or applied 
 in its neighbourhood, than that made in 
 the common manner ; the tarnifh and other 
 inconveniencies, to which common Pruffian 
 blue is fubjedt, feeming to proceed from 
 the acid fpirit, which cannot be totally fe- 
 parated by any ablution He takes no- 
 
 tice alfo of an amufing phcenomenon, which 
 happens upon mixture. When the liquors 
 are well ftirred together, and the circular 
 motion as foon as poffible ftcpt ; fome drops 
 of folution of Vitriol (depurated by long 
 fettling) let fall on different parts of the fur- 
 face, divide, fpread, form curious reprelbn- 
 tations of flowers, trees, fhrubs, flying- in- 
 fects, &c. in great regularity and perfection: 
 Thefe continue ten or twelve minutes ; and 
 on ftirring the liquor again, and dropping in 
 fome more of the folution of Vitriol, are 
 fucceeded by a new picture. 
 
 Mr. Macquer has ingenioufly applied the 
 preparation of this pigment to the dying of 
 wool and filk ; and found means of fixing, 
 the blue fecula in their pores. By dipping 
 cloth firH in a diluted folution of Vitriol and 
 Alum, then in the ley diluted, and after- 
 wards in water acidulated with Spirit of 
 Vitriol, it acquires a light blue colour; 
 which becomes deeper and deeper on re- 
 peating the dippings alternately in the fame 
 order as before ; and adding to the liquors 
 each time a little more of the refpedfive fa- 
 line matters. This blue dye, he fays, ixf 
 beauty and luftre exceeds that of Indigo and 
 Woad as far as fcarlet does the Madder 
 red ; and penetrates the whole fubftance of 
 fulled cloth, without weakening it. The 
 colour is durable in the air, and Hands 
 boiling with Alum water, but is difcharged 
 by Sope, and, without certain precautions, 
 liable to be fpecky or Unequal. See the 
 Memoirs of the French academy fo,r the 
 year 1749. 
 
 ( 0 ) Iron with Nitre.'] A part of the Iron is 
 thus rendered foluble in water along with the 
 alcalized Salt. A mixture of equal parts of 
 Iron filings and Nitre, injected into a 
 ftronglv heated crucible, and after the de- 
 tonation thrown into water, tinges the Iff 
 quor of a violet or purplifh blue colour. 
 This folution however is not permanent: 
 Though the liquor at firfl: paffes through a 
 filter without any feparation of the Iron, 
 yet on Handing for a few hours, the metal 
 falls to the bottom in form of a brick- 
 coloured powder. It is pretty Angu- 
 lar, that volatile alcalies inflantiy precipi- 
 tate the Irpn from this fixed alcaline folu* 
 tion. 
 
74 Metallic Bodies, 
 
 Iron, fwells and grows hot, and if the quantity is large, burfts into flame: From 
 — v— ’ this phcenomenon the chemifls have endeavoured to account for earthquakes, 
 fubt.erraneous fires, and hot mineral fprings. 
 
 Medical hif- Iron is mechanically the moft ufeful, and medicinally the mod falutary, of 
 tery of Iron, all metals ; poffeffing no deleterious power like mod of the others, though 
 its imprudent ule may nevertbelefs be productive of dangerous confequences. 
 Its primary operation is, to conftringe and corroborate: And hence in ca- 
 chexies and chlorcfes, in debilities and relaxations of the folids, it proves a 
 ' medicine of great efficacy •, whild in the oppofite circumdances it is as injuri- 
 ous as in there it is beneficial. Though it always aCts immediately by an 
 adringent quality, it often proves, in its confequential efteCts, aperient; pro- 
 moting natural evacuations where the obftruCtion depends upon a laxity of the 
 veffels; as well as redraining immoderate ones arifing from the fame caufe — 
 A great variety of preparations of it have been employed for medicinal ufe; as 
 folutions in different acids, both mineral and vegetable, by themfelves or in 
 conjunction with vinous fpirits, in their liquid date, or infpiffated or cryftal- 
 lized ; calces or croci made by fire alone, or by precipitation from acids, or 
 by urging the infpiffated or crydallized folutions with a drong fire till the acid 
 has been expelled ; and the rud made by expofing the filings to the air. The 
 crude filings, are often as effectual as any of the preparations : If procured 
 from the workmen in Iron, they fhould be carefully cleanfed by winnowing 
 and walhing. For obtaining the rud mod expeditioufly, the filings fhould be 
 fpread thin, moidened, and fet in a moderate warmth : Mr. Bourdelin ob- 
 serves, that the Iron increafes in weight in this procefs, and that when tho- 
 roughly ruded, fo as to imbibe no more water, it yields in didillation a vola- 
 tile urinous fpirit. Iron combined with acids, proves more adringent than 
 by itfelf ; but when the acid is feparated, and the metal reduced to a calx, its 
 aClivity is greatly diminifhed. The combination with vitriolic acid, or Sal 
 martis , is directed to be made in the fhops, by diffolving Iron filings in the 
 acid, and cryftallizing the folution : This however is a needlefs labour, the 
 
 common green Vitriol, duly purified, being one and the fame thing: If the 
 Vitriol is fufpeCted of containing any Copper, a little frefh Iron added to the 
 folution of it, will effectually precipitate all remains of that metal : Even a 
 pure Vitriol of Copper may be converted into a pure Vitriol of Iron, by dif- 
 folving it in water, and adding Iron to the folution ; the Iron throwing down 
 the Copper, and being diffolved in its place. The vitriolic and vegetable 
 acids are the only ones with which Iron crydallizes or preferves a folid form : 
 The marine renders it moft effectually foluble in Spirit of Wine. 
 
 Hif- Iron is exceeding rarely, if ever, found native in the earth. I have never 
 tory. yet feen a Specimen of pure native Iron; the maffes which have been fhewn 
 
 me as fuch, being either not attracted by the Magnet, or not diffoluble 
 in Aqua fortis. Its ores on the other hand are extremely plentiful in al- 
 moft all parts of Europe : But South America, fo rich in Gold and Sil- 
 ver, has little of this moft ufeful metal. The richeft ores of Iron are 
 sompaCt and ponderous, of a brownifh, reddifh brown or red co- 
 lour u 
 
Metallic Bodies. 
 
 7 $ 
 
 Iour(/>): They fcarcely ever participate of perfedl Sulphur (the Pyritae ex- I r o n. 
 cepted) and contain but little foreign matter: Such are, the Magnet, the U — 
 Haematites or Blood-ftone, the common Iron-ftone, and Ruddle. The running 
 down of the Iron-ftone requires no particular management, a ftrong charcoal 
 fire being the principal point: The ore is thrown in among the burning fuel, 
 with the addition fometimes of Quick-lime or Lime-ftone (q). 
 
 Be Tides 
 
 (p) Iron ores.] Some of the Iron ores, in co- 
 
 lour and appearance, do not ill refemblelron 
 itfelf ; as the grey ore of Derbyfhire, and 
 the bluifh of the foreft of Dean in Glou- 
 cefterfhire : Moft of the Swedifh ores are 
 likewife of this kind. Others are blackifh, 
 brown, red, yellowifh, or rufty coloured : 
 Thefe are the moft common forts in Eng- 
 land and in Germany. There is one very 
 fingular lpecies, of a ftriated texture, a pale 
 yellowifh or greyifh colour, oftentimes 
 white, and in fome degree pellucid : This, 
 though in its crude ftate it promifes nothing 
 metallic, on being moderately calcined, 
 difcovers, by the deep colour it affumes, 
 that it abounds ( with Iron : Cramer in- 
 forms us, that it gives out, on fufion, from 
 thirty to fixty pounds of excellent Iron upon 
 the hundred. Some of the richer ores yield 
 no lefs than eighty on the hundred Dif- 
 
 ferent kinds of Iron-ftone are, in fome 
 mines, found adhering to the tops of ca- 
 verns in form of icicles or ftriae, fometimes 
 irregularly cluftered together, fometimes 
 hanging down like the briftles of a brufh : 
 Whence the name Brufh-iron-ore. Other 
 particular forms of the Iron-ftone have oc- 
 cafioned a variety of fanciful names, to be 
 met with in fome of the metallurgic writers. 
 
 (q) Smelting of Iron ores,] The ores of 
 Iron are commonly calcined previous to the 
 fufion ; the harder ones, though they fhould 
 contain nothing fulphureous or arfcnical, 
 requiring that procefs to render them pul- 
 verable* In the large works, a quantity of 
 the ore is placed on a bottom of wood or 
 charcoal, intermingled with ftrata of the 
 fame kind of fuel ; the pile carried up to a 
 confiderable height, and fet on fire. 
 
 The fufion is performed in furnaces 
 twenty or thirty feet high, and eight or ten 
 feet wide in the middle, but narrower above 
 and below. The furnace is charged at 
 top with charcoal, and the fire excited by 
 Urge bellows moved by water. When the 
 
 whole internal Surface appears of a ftrong 
 white heat, the ore is thrown in, by little 
 at a time, with more charcoal over it, and 
 commonly a portion ofLimeftone, the true 
 ufe of which is probably, not as has been 
 generally fuppofed, to abforb Sulphur, but 
 to promote the fufion (fee page 18.} The 
 ore, gradually melting, drops down through 
 the fuel into the receiver or bottom of the 
 furnace, where a paffage is open, for tak- 
 ing off the fcum or drofs. The metal, now 
 in ftrong fufion, is let out, by a tap-hole, 
 into furrows made in a bed of fand : The 
 large mafs, which fets in the main furrow, 
 is called by the workmen a few, and the 
 leffer ones pigs of Iron. Chimney backs, 
 ftoves, garden-rollers, &c. are formed of 
 this rough metal taken out of the receivers 
 with ladles and caft into moulds made of 
 fine fand. Two or three tuns of Iron, are 
 run off in twenty-four hours : Before the 
 force of water was called in aid to work the 
 bellows,, Scarce an hundred weight could 
 be obtained in a day, and a large quantity 
 of the metal was left in the drofs : Hence, 
 in fome places, the flags of the old works 
 are now remelted to advantage along with 
 frefh ore. From the richnefs of the flags of 
 different ores left by former times, fome 
 have been milled into an opinion, that the 
 metal was regenerated in them-. 
 
 From the great confumption of wood in 
 this bufinefs, and its Scarcity in fome 
 place's where there are rich mines of Iron, 
 attempts have been made to fubftitute other 
 fuels. Peat has been found to anfwer to- 
 lerably well; In fome parts of England, a 
 quantity of this has for a Considerable time 
 been mixed with the charcoal ; and a patent 
 has been lately obtained for running down 
 the ore with peat alone. Pitcoal fen- 
 ders the Iron hard and brittle : This incon- 
 venience is Said to be in good meafure pre- 
 vented, by previoufly coaking the coal, 
 as" is cuftomary to fit it for the drying of 
 malt. 
 
 2 Tfeg 
 
7 6 
 
 Iron. 
 
 Contained in 
 coloured 
 earths and 
 ftones, 
 in animals 
 and vegeta- 
 bles. 
 
 Differences in 
 its quality. 
 
 M E T A L L I C B O D I E S. 
 
 Bcfides the minerals which are commonly worked for Iron, there are many 
 others in which imaller quantities are contained : From this metal the coloured 
 clays and boles, and even the precious Hones, receive their colour. Iron is 
 truly an univerfal metal : Some portion of it has been difcovered in all the 
 mineral earths and Hones that have been examined, in the ores of all other 
 metals, and even in the allies of vegetables and animals. It was long dif- 
 puted betwixt two of the French academicians, Lemery and the elder Geoffroy, 
 whether the Iron difcovered by the magnet in vegetable allies, pre-exiHed in 
 the plant, or was produced in the burning: Mr. Geoffroy ’s opinion is evi- 
 dently the true one, namely, that the ferrugineous earth or calx exiffs in the 
 vegetable,, and is reduced into perfect Iron by fome of the inflammable matter 
 ot the fubjeCt combined with it in the fire. The mineral earths and Hones im- 
 pregnated with Iron, and even its richeHores, contain no other than this calx 
 of Iron 3 and no art can extract from them a grain of metal, without the intro- 
 duction of inflammable matter. 
 
 Iron proves greatly different in hardnefs, brittlenefs, malleability, &V. ac- 
 cording to the quality of the ore it is obtained from (r), and the operation it 
 has undergone. As HrH run from the ore, it contains an admixture of crude 
 earth not perfectly reduced to a metallic form, and hence proves hard and 
 brittle (j) : By repeated forgings, this earth is forced out from its pores, and 
 
 the 
 
 The impure Iron, as run from the ore, completely forged Iron, cannot be worked 
 is melted down in another furnace, in- either as Steel or Iron. The Swedilh, and 
 terfnixt with charcoal ; a ftrong blaft of fome of our own ores, yield an excellent 
 air being impelled on the furface of the me- tough Iron 3 whilft others give a brittle 
 tal, by which its fufion is remarkably pro - metal that cannot by any forging be made 
 moted. On difcontinuing the action of the perfectly malleable, and hence employed 
 bellows, the Iron thickens into a mafs call- only for fome kinds of nails and heavy 
 
 cd a loop , which is conveyed under 3 * Barge works. The inferior ores are faid to be 
 
 hammer raifed by the motion of a water- meliorated by mixing two or three different 
 wheel. The Iron, beat into a thick fquare, forts together, 
 is heated till ready to melt, and forged 
 
 again : By a few repetitions of this procefs, (5) Cajl Iron.] Pure caff Iron is for the 
 
 it becomes completely malleable, and is at moft part fo hard, as not to yield in the 
 
 length formed into bars for fale. A large leaft to the file or the chifel; and extremely 
 quantity of vitreous fcoria feparates both in brittle, both whilft cold and when ignited : 
 the fufion and the forging : The rough caff Caff into thin plates, it cracks, on being- 
 iron, obtained from fome ores, lofes more haftily cooled, like glafs. Broke, it ap- 
 tiian half its weight in being made into pears of a dull white colour, approaching to 
 bars. that of unpolilhed Silver 3 and of a fmooth 
 
 and uniform texture, compofed of plates 
 
 (r) Differences according to the quality of the laid fo clofe together as fcarce to be diftin- 
 
 oye. ] There are very remarkable differences guifhable even by a microfcope The 
 
 in the Iron obtained from different ores : more impure forts are lefs hard to the file. 
 
 From what particular admixtures or other but not lefs brittle under the hammer: 
 caufes they proceed, has hitherto been too Their colour is much darker, fometimes a 
 little examined. The Iron run from fome dufky grey, fometimes alinoft black 3 their 
 of the German ores, when forged only to a texture often granulated. On melting 
 certain point, is found to be a good Steel ; them, a quantity of glaffy fcoria arifes to 
 whilft that of many others, taken in the the furface 3 which, taken off, leaves the 
 fiime intermediate ftate betwixt caff and metal pure and white like the foregoing fort. 
 
 Pure- 
 
Metallic Bodies. 77 
 
 the metal becomes fofter and more malleable (/). The workmen commonly Iron. 
 judge of the goodneis of call Iron, from its bearing a ilrong fire, when made w — 
 into vefiels, without bliftering ; and of that of forget! Iron, from its being 
 
 malleable 
 
 Pure call Iron, (unrounded with animal 
 afhes, and expofed to a fire not fufficient to 
 melt it, becomes in a fhorter or longer 
 time, according to the ftrength of the fire 
 and the thicknefs of the metal, fo foft, that 
 ornaments or utenfils made of it, however 
 hard before, may now be eafily cut, filed, 
 embellifhed, or freed from their fuperfluities. 
 The gradual changes, produced in this pro- 
 cefs aie pretty remarkable. 
 
 Iron, fuffered to cool in the mould, ap- 
 pears on the furface of a date blue colour ; 
 a fure mark of its being hard. After the 
 cementation has been continued for a cer- 
 tain time, it looks externally of a dark 
 coffee or blackifh colour, internally far Jefs 
 white than before, and no longer of a 
 fmooth, but of a rough granulated ftrudlure. 
 In this Hate, it yields to the file if flowly 
 cooled ; but if cooled haftily by quenching 
 in water, or if heated a fecond time and 
 then quenched, it is not touched by the 
 tool : Hence works of caff Iron, foftened 
 to this degree, may be filed or cut, and 
 afterwards readily hardened again. It does 
 not bear the hammer when cold, but proves 
 in fome meafure malleable when ignited : 
 When ftrongly heated, I have generally 
 found it crack or fly in pieces from a mo- 
 derate blow. 
 
 On further continuing the cementation, 
 the dark colour which the metal had before 
 acquired, gradually goes off, and at length 
 changes into a white, with a confiderable 
 degree of brightnefs, which the Iron had 
 nothing of atfirft: The texture likewife al- 
 ters, but not equally in all kinds of Iron, 
 fome proving granulated and others plated. 
 The metal is now fully foftened : It may be 
 eafily cut with a chifel, bent without break- 
 ing, and extended under the hammer : Nor 
 does it acquire any confiderable hardnefs on 
 being heated and quenched in cold liquois. 
 
 In proportion as the Iron becomes foft, 
 it lofes of its fufibility. If the cementation 
 is continued only till the outfide is foftened; 
 on railing the fire, all the inner hard core 
 will melt and run out, leaving the outer 
 foft part entire, and of its original form. If 
 
 any part of the furface is covered with fan.', 
 or left uncovered with the foftening mat- 
 ter, the melted core will run out there. 
 
 Sand or powdered Flint fomewhat retard 
 the foftening. Argillaceous and gypleoum 
 earths, particularly the latter, occaiion the 
 Iron to fcale greatly. The mineral cal- 
 careous earths have nearly the fame effect as 
 animal afhes, but with lefs certainty : After 
 the Iron has been foftened by them in a 
 moderate fire, it fometimes, in a flronger, 
 refumes its original hardnefs : They are 
 likewife apt to make the furface fcale, and 
 thus obliterate the finer imprefiions received 
 from the mould. Bone-afh itfelf is fubjedl 
 alfo to this laft inconvenience, where the 
 largenefs of the mafs of metal requires the 
 fire to be long continued : The admixture 
 of a little powdered charcoal prevents the 
 fcaling, without feeming to affect the fof’t- 
 nefs or hardnefs. 
 
 The foregoing obfervations are drawn 
 chiefiy from the experiments of M. de Reau- 
 mur referred to by our author, I have 
 added not a few of my own ; but without 
 being able to add much to the confequences 
 deducible from his ; or to difcover the prin- 
 ciple on which the change is effected ; or to 
 foften the pureft and fineft call Iron near 
 fo effectually by cementation as by forging. 
 
 (*) Forged Iron.'] When caft Iron is heated 
 till ready to melt, and compreffed by re- 
 peated blows of large hammers ; a quantity 
 of vitreous matter is forced out and thrown 
 of? ; its parts are more regularly arranged ; 
 the plates rendered fmaller and more dif~ 
 tindf, by degrees changed into grains, and 
 at length into fibres. Fine plates regularly 
 arranged,, final! grains, or, fibres like thofe 
 which appear upon the fradture of wood, 
 are marks of tough Iron, provided it is riot 
 fulphurated : Large and irregular plated 
 
 Irons are univerfally ftiort or brittle. The- 
 colour of the fradfure is ufually whitifh and 
 confiderably bright ; though fome, even off 
 the better forts of Iron, look dull, without, 
 any brightnefs. 
 
 Pure well forged Iron is malleable both 
 
 when 
 
78 
 
 I R 
 
 •Steel 
 
 Metallic Bodies, 
 
 n. malleable both when hot and cold, making good Steel, and lading well whert 
 — ' employed for fuch ufes as require it to be kept wet, as in pegs for the axletrees 
 of mill-wheels, &c. 
 
 Forged Iron is converted into Steel, by cementation, in clofe veflels, with 
 inflammable and faline fubftances, as the horns and hoofs of animals, or mix- 
 tures of Sea-falt, foot, and wood alhes. Steel is much harder, more brittle, 
 and more elaftic than the Iron was at firft ; and all thefe qualities are in good 
 meafure at the command of the artift. Heated a little, and quenched in water, 
 it proves extremely hard : By an increafe of the heat, it becomes fofter and 
 l'ofter ; and by a continuance or repetitions of it, returns into Iron again ; 
 lofing by degrees the inflammable or other principles, the introduction of which 
 had made it Steel (a). The hard call Iron, as well as Steel, is rendered foft, 
 
 by 
 
 wheil cold and hot, though not with equal 
 facility : The further it is heated, it extends 
 the more eafily, and is the lefs liable to 
 crack — - — Some forts of Iron, though malle- 
 able when cold, prove entirely brittle if 
 heated red ; others are brittle when cold, 
 and malleable only whilft: ignited :■ The for- 
 mer are called by the workmen red^Jhare i 
 the latter cold-Jhare Irons. The imperfection 
 of the firft is fuppofed to be owing to an 
 admixture of Sulphur: That of the fecond 
 
 proceeds wholly from a want of fufficient 
 forging— Forged Iron is a little heavier 
 than the caft; in the proportion of about 
 7 t 8 c to 7r'o. It fcorifies much more in the 
 fire, and does not melt without additions 
 or the immediate contact of the fuel. 
 
 The author above-mentioned obferves, 
 that the fubftances which foften caft Iron by 
 cementation, increafe the foftnefs of the 
 forged to a certain point : That if the ope- 
 ration is continued beyond this period, they 
 render it harder and more brittle than at 
 ftrft ; that gypfum remarkably promoted the 
 fufion of the metal ; bars of Iron, fur- 
 rounded with gypfum, having fcaled in a 
 moderate heat, and in no very ftrong one 
 melted. It is commonly fuppofed, that 
 Iron, by whatever means it is brought into 
 fufion, totally lofes its malleability : But I 
 have found, that when thus melted with 
 gypfum, it remains malleable in a great de- 
 gree ; and that it will now melt a fecond 
 time, without any addition, and ftill retain 
 its malleability. The Iron, furrounded 
 with the gypfum, did not perfectly melt 
 till the fire had been railed fo high, that 
 the gypfum begun to diflolve the Heflian 
 crucibles-, which were fometimes corroded 
 
 internally to the thinnefs of paper, and 
 fometimes perforated. 
 
 Forged Iron, cemented in clofe veflek 
 with vegetable or animal coals, gains a 
 fenftble increafe both in bulk and weight, 
 
 and now commences Steel — From the 
 
 remarkable changes produced in Iron by 
 earthy and inflammable matters, I was led 
 to fubmit Copper and fome other metals to 
 the fame treatments, but could not obferve 
 that they fuffered any change. 
 
 ( u ) Steel.'] Steel is found to differ in qua- 
 lity according to the particular ingredients^ 
 with which the cementation is performed, 
 as well as the goodnefs of the Iron it is 
 made from. M. de Reaumur obferves, that 
 inflammable fubftances alone, a9 foot, char- 
 coal, animal matters, render the Steel hard 
 to work and apt to crack ; that the admix- 
 ture of abforbent earths, as wood allies, 
 prevents this inconvenience; that a little 
 Sea-fair, added to thefe, contributes to the 
 finenefs and durability of the Steel, and at 
 the fame time expedites the change ; whilft: 
 fome other faline fubftances, as Sal ammo- 
 niac, Sandiver, Vitriol, alcalized Nitre, 
 rendered it far lefs durable. The cementa- 
 tion has been ufually performed in earthen 
 coffins or chefts, fitted with covers, of fuf- 
 ficient capacity to receive a great number of 
 bars at once. There is a large Steel-work 
 in Yorkfhire, where the furnace itfelf is di- 
 vided into partitions or chambers for receiv- 
 ing the Iron with the cementing mixture, 
 with fpaces between for the paftage of the 
 fire: The fire is raifed by degrees for a 
 week, and then fuffered to decay of itfelf. 
 The increafe which the Iron gains in this 
 
 procefe 
 
Metalli 
 
 procefs is faid to be fo confiderable, as to 
 bear the charges of the fuel The cafe- 
 
 hardening of Iron, by cementing it for a 
 little time with burnt horns, leather, and 
 other like fubftances, is no other than a 
 fuperficial converfion of it into Steel. 
 
 Steel, fuffered to cool ieifurely in the 
 furnace, yields to the file ; breaks, whilft 
 cold, from a moderate blow ; and difeovers 
 a laminated texture and dull colour, though 
 the Iron was fibrous and bright before. 
 Confiderably heated, it may be hammered 
 or welded; and if fuddenly cooled, by 
 quenching in cold liquors, proves much 
 harder than at firft, of a bright whitifh fur- 
 face, and no longer of a plated, but of a 
 granulated ftrudture : The grains are larger 
 or finaller according as the Steel is more or 
 lefs hard. Both the texture and colour are 
 always different from thofe of the Iron 
 which it was made from ; though fome 
 kinds of Iron are in thefe refpecls little dif- 
 ferent from fome kinds of Steel. 
 
 A bar of white polilhed Steel, laid upon 
 burning charcoal, fo as to heat fiowly, 
 becomes at firft paler; then of a dilute yel- 
 low, which deepens by degrees into a gold 
 colour: As the heat increafes, the gold co- 
 lour changes to a purple ; this is fucceeded 
 by a violet, and the violet by a deep blue, 
 which weakens infenfibly to a water colour, 
 the laft Ihade that can be diftinguilhed be- 
 fore the bar grows red-hot. All thefe co- 
 lours may be exhibited on the fame bar at 
 once, by applying the heat only at one end ; 
 and fixed or detained upon it, by quenching 
 it in cold water as foon as they appear. 
 
 Thefe different colours are accompanied 
 with manifeft differences in the texture, 
 hardnefs and tenacity of the Steel, and prove 
 fure guides to the workman for giving his 
 fprings and tools the temper proper for each. 
 Steel in its white ftate is exceffively hard, 
 not to be filed, fcratched or cut, and in- 
 capable of receiving any imprefiion or alte- 
 ration of form without extreme violence : 
 Hence it is fit for making dyes to ftamp 
 coins and medals, for forming the furface 
 of anvils, hammers, &c. When yellow, 
 it proves more tractable, yet fufficiently 
 hard to make files, drills and other tools 
 capable of cutting fuch as is of a violet or 
 blue colour. In this laft ftate, it is fome- 
 what foft, fo as to be punched, filed, dril- 
 led, toothed, made into laws; and highly 
 I. 
 
 c B o d i e s. 79 
 
 elaftic, fit for fprings, which may be coiled Iron. 
 or uncoiled without breaking' or injury. . i 
 
 If Steel be cemented afrelh with the 
 Steel-making mixture, or if the procefs at 
 firft be long continued ; the metal proves 
 exceffively brittle, incapable of being weld- 
 ed, apt to crack and fly in pieces in forging, 
 and on railing the fire, melts, like call Iron. 
 Cementation with abforbent earths, or fire 
 alone, change it from this ftate firft into 
 tractable Steel again, and afterwards into 
 malleable Iron, fomewhat finer and purer 
 than the Iron was at firft. 
 
 Mr. Reaumur luppofes that common call 
 Iron itfelf is no other than an impure fpecies 
 of melted Steel ; and that on foftening it, 
 whether by cementation or by forging, it 
 becomes perfect Steel before it becomes 
 malleable Iron. The German Steels are 
 made diredlly from call Iron, by forging it 
 only to a certain point. This kind of Steel 
 is lefs certain in quality than that made from 
 forged Iron, and has generally veins of foft 
 Iron : An account of the manner of prepar- 
 ing it was publilhed fome years ago in a 
 treatife Sur Varier d' A If ace. 
 
 The ancients have been fuppofed, from 
 the hardnefs of fome of the ftatues which 
 they have left us, ant! from the Egyptian 
 obelilks, which though carved with a variety 
 of figures, refill the tools of later ages ; to 
 have had peculiar methods of making Steel 
 of a degree of hardnefs fufficient to cut thofe 
 refractory Hones. Dr. Lifter complains, 
 that this valuable fecret is now loll; and 
 that the proceftes, ufed by molt nations, are 
 a poifoning of Iron by mineral Salts, rather 
 
 than a true making of Steel -So far as 
 
 can be judged from the imperfect accounts 
 given by Ariftotle and Pliny, the ancient 
 Steel was made by keeping forged Iron for 
 a certain time in melted call Iron. Agri- 
 cola deferibes a procefs on the fame prin- 
 ciple, which Kircher allures us was pradtifed 
 in the illand Ilva from the time of the Ro- 
 mans to his own. And this is the method 
 which Lifter propofes, for retrieving the loft 
 fecret -The procefs is- curious, and af- 
 
 fords, by proper management, a perfect 
 Steel, but not fuperior in hardnefs to the 
 common fort. It is probable, that the fe- 
 cret of the ancients did not confift fo much 
 in giving their tools an extraordinary hard— 
 nefs, as in employing the Hones in a fofter 
 ftate than that in. which we now find them. 
 
 There.* 
 
Metallic Bodies. 
 
 by cementation with earthy matters, as bone allies, mixed with a little pow- 
 dered charcoal. See Reaumur’s treatife on the converfion of forged Iron into 
 Steel, and the foftening of caft Iron. 
 
 Some of the ores of Iron are more valuable for other ufes, than for being 
 worked as Iron ores. Such are, (x) 
 
 I. Emery: Smiris, fmerillus, fmyrites, fo called from or c/xeu, to 
 
 cleanfe or polifh. Three forts of this (tone are mentioned by authors ; a 
 golden, cupreous, and ferrugineous Emery. The golden Emery is faid to be 
 
 found 
 
 There are fundry Hones which have their 
 hardnefis improved by long expofure to the 
 air: There are others which in their natu- 
 ral Hate are fo foft as to be eafily cut with a 
 knife and turned in a lathe, but gain from 
 fire a degree of hardnefs which is proof 
 * gain It the chifel. See page 26. 
 
 ( v) Ores valuable for other purpofes.] Such 
 alfo is the lapis heematites or Mood-Hone, the 
 glafs-kopf of the German writers. This is 
 an elegant Iron ore, generally of a reddifh 
 colour, very ponderous, and of great hard- 
 nefs, infomuch as to be ufed, like Emery 
 for polifliing Glafs and Steel. Its figure is 
 fomewhat pyramidal : One fide is convex, 
 the other angular. Broke longitudinally, 
 it exhibits Arise converging to the fmaller 
 end: Its tranfverfe fracture refembles that 
 o\ foft Steel. Expofed to a moderate fire it 
 falls into feales, and in this Hate adheres 
 readily to the magnet, and gives out its 
 Iron to acids; neither of which had any 
 action on it before. In a vehement fire, it 
 yields a white brittle Regulus of Iron, which 
 is very difficultly rendered malleable. Ne- 
 yerthelefs, in fotne parts of Germany, where 
 it is plentiful, it is faid to be worked for 
 Iron to advantage. 
 
 The native red and yellow ochres, em- 
 ployed as pigments by the painters, are no 
 other than ores of Iron, compofed of a 
 calx of the metal blended with an argillace- 
 ous earth : The ponderous deep red ochre 
 called fmit, and the reddle or red chalk, are 
 rich in Iron. Swedenborg informs us, that in 
 fomc provinces of Sweden, different ochres, 
 frequent in marlhy places and at the bot- 
 toms of ponds, are dug in fummer when the 
 waters have dried up, and fmelted for Iron ; 
 that fome yield upwards of one fifth their 
 own weight, though there are others -which 
 C - tee afford one twentieth. 
 
 Manganefe or Perigord Hone, Magnefia , 
 lapis petracorius , the braunftein of the Ger- 
 mans, has hitherto been ranked among the 
 ores of Iron. This mineral is ufually of a 
 dark grey colour ; fometimes bright and 
 Hriated like Antimony ; fometimes dull, 
 with only a few fmall Arise. It is found 
 chiefly in mines of Iron ; though confider- 
 able quantities are likewife met with in the 
 Lead mines of Mendip hills. 
 
 Manganefe, Hrongly calcined, becomes 
 brown. Small proportions of the calx, melted 
 with Borax, with compofitions of Flint and 
 Alcali, or with common Glafs, comunicate 
 different fliades of purplifh or red colours. 
 On continuing the Glafs in Hrong fu- 
 fion, the colour which it had received from 
 the Manganefe difappears, and the effedt of 
 ■fundry other colouring matters alfo is at the 
 fame time deHroyed : Hence the ufe of 
 Manganefe in making colourlefs pellucid 
 glaffes, for confirming any accidental tinge. 
 Larger proportions give a brown or black 
 colour : Hence its ufe in the compofition of 
 black enamels, and in the black glazings for 
 earthen ware. The bright Hriated fort is 
 generally preferred by the glafs-makers, and 
 the other by the potters. 
 
 Mr. Pott has given fome experiments on 
 this mineral ( Mifcellan . Berolinenf. tom. vi.) 
 from which it does not appear to contain anv 
 Iron. He obferves that it is not attracted 
 by the magnet either in its crude Hate, or 
 after it has been expofed to the fire in con- 
 jundtion with inflammable fubHances ; and 
 that it yielded nothing metallic on being 
 urged by a Hrong fire with the common re- 
 ducing flux With twice its weight of 
 
 Nitre, it did not deflagrate ; the mixture 
 boiled up, foon after concreted into a 
 blackifh grey mafs variegated with yellow 
 fpots, leaving on fome parts of the crucible 
 a green or purplifh glazing. The powdered 
 
 mafs 
 
Metallic Bodies. 8i 
 
 found in the Peruvian and other American mines, to be of a reddifh colour, E m ery. 
 to have fmall veins or fpecks of Gold and Silver imbedded in it, to be very u— v— ■«; 
 rare, and its exportation to be prohibited by the King of Spain : The cupre- 
 ous fort, to be likewife reddifh, but more equal and free from veins, to hold 
 no Gold or Silver, and to be found in Copper mines in Europe : The ferrugi- 
 neous, to be of a fparkling whitifli, a dark grey, or a blackifh colour, to be 
 found in rich Iron mines, and to be the lead valuable fort. 
 
 The common Emery, whatever be its colour, whether reddifh, greyifh or Common 
 blackifh, is a compact done, fo hard as to cut Glafs like the diamond ; im- 
 pregnated with Iron, and a very fmall portion of Copper. It is met with in 
 Norway, Sweden, England, Saxony, and other countries : Bruckman re- 
 
 lates that the Emery found at St. Georgendadt in Mifnia is fuperior to the 
 Spanifh. It is ufed for cutting and poiifhing precious dones, for polifhing Its ufes i 
 Agate, Porphyry, Marble, Glafs, metalline Specula, Iron and Steel, and the 
 various utenfils and ornaments made of thefe kinds of fubdances. For thefe 
 purpofes, the Emery is ground in mills, the powder paffed through fieves of 
 different degrees- of finenefs, and thus divided into different fortments, the 
 fineft of which are, for the nicer ufes, further divided by wafhing them over 
 feveral times with water. The refufe Emery, in grinding, or fuch as has 
 been ufed in polifhing, is, in France, dried and kept apart under the name of 
 potee d’ Emery. Some have employed powdered Emery, from its power of 
 polifhing hard ftones, as a dentifrice : But for this ufe it is by no means pro- 
 per, as it wears off the natural polifh of the teeth. It has been faid that 
 
 Emery gives out fome red matter on the whetdone : Where this has been ob- 
 ferved, the Emery employed mud have been the red kind, or a fpecies of 
 haematites; for the others yield only a grey colour on the done. 
 
 I have tried to fmelt this mineral with the feveral fluxes ufed in affays forExamined by 
 Iron, as alcaline Salt, Borax, Charcoal dud. Pitch, Tallow, Efr. but could 6 rc > 
 not procure a fire fufficiently drong to fully mader the refractory dony mat- 
 ter: Though there was not, however, any perfect Regulus of Iron obtained, 
 
 there 
 
 mafs did not deliquiate in the air : On the 
 affufion of warm water, it acquired an ele- 
 gant green colour, which was foon fuc- 
 ceeded by a blue and a purple, and then 
 returned into green again : On fhaking the 
 Glafs, the fame beautiful fucceffions of co- 
 lour repeatedly appear. The green folu- 
 tion, palled through a filter, and digelled or 
 boiled, lofes its colour, depofiting a fine 
 yellow powder, which calcines brown, dif- 
 folves in acids, and is not precipitated by 
 alcaline Salts The fame phcenomena 
 were obferved on treating the Manganefe 
 with fixed alcalies inftead of Nitre — -—Acids 
 have no effect upon crude Manganefe, but 
 partially diffolve it when calcined : The fo- 
 Iutions are colourlefs, except that made with 
 Spirit of Vitriol, which has a flight rofe co- 
 lour : On adding alcalies, a white earth is 
 
 precipitated- — —Sal ammoniac elevates no- 
 thing from it in fubiimation, but parts with 
 a little of its own urinous fpirit : The refi- 
 duum, which appears of a reddifh colour, 
 partly diffolves in water, leaving a whitifh 
 earth : The folution coagulates with alca- 
 line Lixivia — —Calcined with Sulphur, it 
 forms a yellowifh brown mafs, which yields, 
 with water, a large quantity of a white cry- 
 ftalhne Salt, of a bitterifh aftringent taffe 
 followed by a kind of fweetnefs. This 
 Salt yields in diftillation a fulphureous 
 phlegm, and a little ammoniacal Sublimate, 
 but no acid fpirit : The refiduum taftes like 
 burnt Alum, but more acid. A folution of 
 the Salt effervefces with alcalies, and depo- 
 fites a white earth : It does not change co- 
 lour with Galls. 
 
 M 
 
S 2 Metallic Bodies. 
 
 Emery, there were abundance of particles which the Magnet attracted. Emery in its-. 
 u— - v — crude date is not affecded by the Magnet. All acids extradl fame what from-, 
 by acids , &c. g m ery, but none of them diffolve one half of it. In each of the foliow- 
 ing experiments was employed half an ounce of the mendruum, and fixtv grains 
 of the powdered done. Spirit of Nitre diffolved only thirteen grains out of 
 the fixty; the folution looked flightly yellowifh, the refiduumof apalebrowm 
 Spirit of Salt took up feventeen grains, and acquired a gold-yellow tindlure, 
 leaving the powder of a pale brown. Aqua regia diffolved twenty grains, and 
 acquired a like yellow colour, leaving a yellowifh brown powder. Spirit of 
 Vitriol diffolved twenty-four grains; the liquor continued colourlefs, the refi- 
 duum greyifli brown. Oil of Vitriol feemed to adt upon the powder, to corrode 
 and render it white; but no true folution enfued. Fixed alcaline Lixivia had no 
 effedt; but volatile fpirits extradled a blue tindlure, and took up about half a> 
 grain out of the fixty grains of Emery: The remaining powder looked reddifh 
 brown. Infufions of Galls, mixed with Oil of Vitriol that had been digeded 
 on Emery, depofited a white Precipitate ; with the folution or extradlion made 
 with Spirit of Vitriol, a grey Precipitate; with the tindlure in Spirit of Nitre,, 
 a brown one ; with that in Aqua regis, a blackifh brown ; with the tindlure 
 made in Spirit of Salt, the liquor feemed at firfl to become inky,, but on 
 (landing, the colouring matter precipitated. 
 
 SopViflicati- The alchymifts have expedted extraordinary effedls from this mineral, and 
 on of Gold pretended by its means to fix Mercury, to augment Gold, £sk. They have 
 with Smirts. m ixed with Gold an extradlum fmiridis , and thus increafed indeed the quantity, 
 but proportionably debafed the quality of the Gold ; for the matter fo intro- 
 duced is by no means true Gold, and does not (land the teds of that metal : 
 An experienced artifl obferves, that on amalgamation with Mercury, the ad- 
 ventitious matter is feparated and thrown out, almoft as Calamine is from 
 Bra/s by a like treatment, and thus difcovers that it is of a different nature 
 from Gold. There is no real Gold to be obtained from the European Eme- 
 ries ; that fome fliould be got from the Peruvian, is little wonder, native Gold 
 being imbedded in that, as in the other (tones in the Gold mines. 
 
 ^Magnet. 11- The Loadstone or Magnet: Magnes ,. lapis Heracleus , lapis Hercu - 
 > - > leus, lapis Lydias , lapis Nauticus , Si derites. This (lone is externally of a 
 
 blackifh, a brown, or a brownifh grey colour ; fotnetimes compadt, and mo- 
 derately hard; fometimes foft, porous, and brittle. The bed I have feen 
 were of a blackifh hue, or at lead more of a brown than a grey, much refem- 
 bling old Iron. It is found in all the four quarters of the world, though not 
 in each of the provinces into which they are fubdivided; in the Eaft-Indies, 
 Ethiopia, Macedonia, Boeotia, in Spain, France, Norway, Ruffia, Scot- 
 land, England, Sweden, Italy, Pruffia, Hungary, Bohemia, Lithuania, Ger- 
 many ; more particularly in Saxony and Sweden ; fometimes indidindt mines, 
 but mod frequently along with the more common ores of Iron. In Saxony, 
 the bed Magnets are met with at Ehrenfriederfdorf, Schwartzenberg, and Brei- 
 tenbrunn. Thefe dones were formerly divided according to the different 
 countries they were brought from : But this circumdance is now difregarded, 
 the value depending wholly upon their qualities. 
 
 The 
 
Metallic Bodies, , 83 
 
 The diftinguiflfing chara&ers of the Loadftone are, that it attradls Iron (Magnet. 
 and that when placed fo as to move round with very little friftion, as when ' — -v — — J 
 fufpended by a thread, or laid on a piece of cork floating in water, a certain l£ u s ifi ^ n ’ ha 
 point or pole turns always northwards, and another oppofite one fouthwards. rafters 2 
 The firft of thefe properties renders it ufeful to the chymift for difcovering or 
 feparating lmall particles of Iron mixed with other matters : By the fecond, it 
 proves an invaluable guide to the feaman. 
 
 The Magnet attrafts no other fubflance but Iron-, and Iron only in its per- Attraaive 
 ; fedt metallic flats : It does not touch the calces or croci, or fulphurated Iron, power, 
 and ads but on few of the ores, till art has freed them from their Sulphur, or 
 impregnated them with inflammable matter (y). Henckel obferves, that it 
 attradslron when mixed with confiderable proportions of fundry other metals ; 
 of Gold, Silver, Copper, Brafs, Tin, Zinc, Bifmuth, and Arfenic -, but dif- 
 covers no adion upon Iron that has any admixture of Regulus of Antimony. 
 
 If Iron be mixed only fuperficially, in filings, with any other metallic body, a 
 cautious application of the Magnet will extrad the Iron ; though a vigorous 
 Magnet, haftily applied, will take up the filings of the other metal intermixed 
 among thofe of the Iron. If a Magnet be rolled in Iron filings, a few of the 
 filings will adhere all over its furface-, but they will be plentifully accumulated 
 on two particular points of the ftone, and thefe points are its poles. It attrads 
 Iron without adual contad, and in different media -, in vacuo, in air, in 
 water, with the interpofition of various folid bodies, wood, glafs, ftones, me- 
 tals, &V. The degree of attradive power differs in different Magnets : In the 
 hiftory of the French Academy for the year 1702, there is an account of a 
 Loadftone in Holland, which weighed but ten ounces, and lifted eighteen 
 pounds, that is, above forty times its own weight : Tergazzi mentions a Mag- 
 net which lifted fixty j and Boyle, one which lifted eighty times its weight. 
 
 This laft is probably the ftone taken notice of by father Bonanni (in the 
 Mufreum Kircherianum , p. 203.) which weighed no more than two ounces, and 
 fuftained ten pounds. I have myfelf feen fome which bore four, fix, eight, 
 ten, twenty times their own weight: The largeft I everfaw was one found in 
 Devonfhire and kept in the Mufeum of the Royal Society in London: This 
 weighs fixty pounds, but does not lift much, though it moves a compals 
 needle at the diltance of nine feet. The power is greatly increafed by arming, 
 as it is called, or uniting the virtues of both poles by means of flat pieces of 
 Iron of a proper thicknefs. Lani relates, that he had a Magnet which, un- 
 armed, lifted only fifty- four grains -, but when armed, eight hundred and 
 four. Schottus mentions a Magnet in the poflefiion of the grand Duke of 
 
 Florence, 
 
 (y) Adion of the Magnet on Iron ores.] It is Loadftone, and revived into their metallic 
 obfervable, that feveral of the hard ores of form, each particle appearing now to be 
 Iron, which are not affedted in the leaft by perfedl Iron ; whilit the calces of other me- 
 the Magnet in their natural ftate, are vigo- tals are in no degree revived without being 
 roufiy attracted by it when moderately brought into fufion. It is probably this re- 
 roafted, though, without the contact of any vival of the calx of Iron that Macquer 
 inflammable, and without feeming to lofe means, when he fays it melts fooner than 
 any fulphureous, matter: And that the Ironitfelf; for it does not melt at all in any 
 calces of Iron, by flight roafting with in- degree of fire that can be excited in the fur- 
 flammable additions, are made to obey the nace of the chemift. 
 
 M 2 
 
84 Metallic Bodies, 
 
 M agnet. Florence, which weighed twenty-nine pounds, and lifted fixty-five : Manfre- 
 dusSettala had one, which weighed but a pound, and lifted fixty pounds. It 
 may be obferved, that the Iron, appended to the armature, adheres only by 
 two points or lines, and will be retained rather more firmly when the furface is 
 rounded, than when it is fiat. If a circular plate of Iron be made to fpin 
 upon a table, and in that (late taken up by a Magnet, it continues fpinning for 
 a time as it hangs from the fione. 
 
 Communica- The Magnet communicates to Iron drawn over one of its poles, both its 
 t:u’e and re- attractive and directive power, without lofing any virtue itfelf : Hence compafs 
 puluve pow- needles, and magnetic Steel bars : The harder the metal, the more difficultly it 
 receives, and the longer it retains, the magnetic power. Each of thefe has 
 two poles, like the natural Magnets : Either pole attracts common Iron or 
 Steel : But the North-pole of one Magnet repels the North-pole of another,- 
 whether natural or artificial ; and the South-pole repels the South : Oppofite 
 poles attract each other : Iron rendered magnetic by one pole of a Magnet, has 
 its virtue deftroyed by touching it on the other. Iron is capable of being ren- 
 dered magnetic, and ftrongly fo, without the affiftance of any natural Load- 
 ftone : See fome curious papers on this fubjeCt in the Philofophical Tranfaftions-- 
 Dlreftive The direction of the Magnet or magnetic needle is not always in the plane 
 power. of the true meridian ; but declines towards the Eaft or Weft, more or lefs in 
 different places, and in one place at different times. One end of a needle, 
 when made magnetic, inclines below the horizontal plane : In northern lati- 
 tudes it is the North, and in fouthern ones the South-pole which dips. 
 
 Its power The virtue of Magnets is weakened, by moifture of every kind; by undbu- 
 weakened ous or oily fubftances ; by all Salts, v/hether in a folid form or diffolved ; by 
 and deftroy- being long kept in the neighbourhood of another Magnet, or without any 
 charge of Iron ; by the Iron in contact with the ftone becoming rufty. A 
 Magnet reduced into powder, immediately lofes all its virtue ; as fome fragrant 
 flowers lofe all their fmell on being bruifed : The powdered Loadftone, far 
 from being able to attract Iron, is fcarcely itfelf attracted by a vigorous Mag- 
 net. How ridiculous then the practice, by fome recommended, of mixing 
 powdered Loadftone in plafters, for extracting Iron out of the flefti! 
 
 Muffchenbroek relates that the power of the Magnet is not deftroyed by 
 lire ; that on the contrary, a Magnet which has loft its power by being pulve- 
 rifed, recovers it again, fo as to adhere to a frefia Magnet, by reverberation in 
 a ftrong fire. That author appears, throughout his treatife on this lubjeCt, an 
 able philofopher and mathematician, but no chymift : The powdered Load- 
 ftone is a ferrugineous ore, and is no more attra&ed than the common ores of 
 Iron in their natural ftate : By calcination, in contadt with flame or inflam- 
 
 mable matter, the Iron is revived into its metallic form, and the powder ad- 
 heres to a Magnet, not as being itfelf a Magnet, but as being Iron. 
 
 Examined by The Magnet calcines to a reddifh brown colour; and melted with infiam- 
 iire and men- m able fluxes, yields a confiderable portion of true Iron. Sal ammoniac fub- 
 ftrua. limed from it, elevates fo much of the Iron as to acquire a yellow colour, in 
 
 the lame manner as when fublimed from Iron filings. Spirit of Nitre totally 
 diffolved it into a yellow liquor, which on Handing depofited a fmall quantity 
 of yellowifh Precipitate, amounting to about a grain and a half from thirty 
 
 5 B rains 
 
8 e 
 
 Metallic Bodies. 
 
 grains of the ftone, Spirit of Salt diffolved only twenty-five grains out oFjMagnet. 
 thirty : Both the folution, and the undifiolved powder appeared yellow. Spi- 
 rit of Vitriol diffolved fourteen grains out of thirty ; and Oil of Vitriol corroded 
 twenty grains into a white calx. No vitriolic cryftals were obtained by eva- 
 porating the folution made in the vitriolic acid. 
 
 IV. T I N. 
 
 ^T 1 ! N, Jupiter , is a white Silver-coloured metal, not at all fonorous or ela- T i n, 
 
 flic, a little harder than Lead, fofter than any of the other metals, very \ 
 
 duClile, fo as to be beat into thin leaves (2). It is the lighted: of all the malle- Fuhbility. 
 able, metals ; being little more than feven times heavier than an equal bulk 
 of water. 
 
 , It melts in the fire before it grows red-hot; and on continuing the fire, and 
 frequently Birring the fluid metal,, ilowly calcines into a white powder {a). 
 
 Though Tin itfeif is fo eafy of fufion, its calx is extremely refractory [b ) ; 
 not flying off in the fire, as Boerhaave pretends ; but ftanding the greateft 
 heat procurable in our furnaces, without melting or fuffering any attraction 
 Even when mixed with fufible vitreous matters, it does not perfectly melt with 
 them, but renders a large proportion of the Glafs opake and milky : Nor is it 
 eafily reducible into Tin again. 
 
 Though Tin, of itfeif, is fo foft and fo unfonorous; it furprizingly im-Efiefts on 
 proves the fonoroufnefs, and deftroys the duCtility, of fome of the other me- tlier metals, 
 cals, particularly Gold, Silver, Copper, and Brafs. Bell-metal, the mo ft fo- 
 norous 
 
 (2) Tin — du/rtile.] Tin is commonly reck- 
 oned the leaf: duCtile of all the malleable 
 metals except Lead : In regard to duCtility 
 into wire, it certainly is fo ; but in regard 
 to extenfibility into leaves, it is not. Thele 
 two properties fee m to be lefs connected 
 with one another than is generally ima- 
 gined : Iron and Steel are drawn into ex- 
 quifitely fine wire, but cannot be beat into 
 leaves: Tin, on the other hand, is beat 
 into fine leaf, and cannot be drawn into 
 wire. Gold and Silver poffefs both proper- 
 ties, the mofl: eminently of all metallic bo- 
 dies : Whilft Lead, notwithftanding its flexi- 
 bility and foftnefs, cannot be made either 
 into leaves or wire of any finenefs. 
 
 [a) In the fire.'] It melts the moft eafily of 
 all the metals ; about the four hundred and 
 thirtieth degree of Fahrenheit’s thermome- 
 ter— — Heated till almoft ready to melt, it 
 proves extremely brittle: Large blocks, are 
 in this ftate, eafily beat in pieces from a 
 blow : The purer fort, from the facility of 
 its breaking into long fhining pieces, is 
 called grain Tin. Melted, and nimbly agi- 
 
 tated at the inftanf of its beginning to con- 
 geal, it is reduced into fmall grains or 
 powder. 
 
 In calcination, it contracts on the furface 
 a brownifh grey powdery pellicle ; which, 
 on raifing the fire to a cherry red, fwells 
 and burfts, and difcharges a fmall bright 
 white flame of’ an arfentcal fmeil. The 
 metal, when juft calcined, appears of a 
 dufky greyifh or afh colour : By a longer 
 continuance of the fire, it becomes white, 
 the more fo in proportion as the Tin was 
 the more pure. 
 
 G) Calx unfufible .] It is the moft refrac- 
 tory of all ►metallic calces, that of Platina • 
 excepted. Even in the focus of large burn- 
 ing-glades and miirors, it only foftens a. 
 little and forms cryftalline filaments. With 
 glafs of Bifmuth, and the fimple andarfeni- 
 cated glaftes of Lead, the moft powerful 
 fluxes known for refractory calces, it does 
 not perfectly vitrify, forming only opake 
 milky compounds. By this property it is 
 fitted for making the bafis of the imperfeCT 
 glafles called enamels. 
 
86 
 
 T I N. 
 
 Metallic Bodies. 
 
 norous of all metallic bodies, is a compofition of Copper and Tin. The trri- 
 u— % — — ' nuteft portion, even the vapour of Tin, renders many ounces and even pounds 
 of Gold or Silver, fo brittle as to fall in pieces under the hammer. The leaft 
 particle of Tin, falling on the ftones, or luting of a furnace, will make all the 
 Gold and Silver melted in it, hard and brittle: From fuch an accident, the 
 Gold and Silver-fmiths are obliged to pull down the whole furnace, and build 
 a new one with frefh materials. 
 
 Differences Tin has been fuppofed by fome to be nearly allied to Lead; as approaching 
 from Lead, to it in colour, foftnefs, fufibility, and calcinability. The differences how- 
 ever are much greater than the refemblances ; Lead being far heavier than Tin ; 
 running eafily into a tranfparent Glafs, whilft Tin does not vitrify at ail ; not 
 producing, in the malleable metals that remarkable brittlenefs, which has pro- 
 cured Tin the title of diabolus metallorum. 
 
 Tin and Iron Tin, the mod fufible, and Iron the mod refractory, of the metals, unite 
 
 expo fed to eafily with one another, and feem to have a great affinity (c). On mixing 
 a burning- them 
 
 in the focus of Tfchirnhaus’s burning glals, I obferved, that when the 
 ^ Tin was melted firft, and the Iron added, they united together very quietly ; but 
 
 that when the Iron was melted firft, the addition of Tin occafioned a crackling, 
 and a fputtering of little globules, which burft with a confiderable fiiap : In- 
 ftead of fumes, there arofe-exceeding fine filaments, which ftuck to the 
 clothes, &V. like cobwebs. 
 
 Tin deflagrates ftrongly with Nitre, and alcalifes the Salt. The filings, held 
 in the flame of a candle, yield afmell refembling that of Garlic, and thus ap- 
 pear to contain an arfenical matter (d) : Hence the ill effedts of Tin on thofe 
 who are much expofed to its vapours. 
 
 Tin 
 
 (c) Affinity of Tin and Iron."] Iron is dif- 
 folved by melted Tin, in a heat far lefs than 
 that in which Iron by itfelf melts : The 
 compound is white and brittle. Iron, added 
 to a mixture of Tin and Lead in fufion, 
 takes up the Tin, leaving the Lead at the 
 bottom : And in like manner, if Lead, Tin 
 and Silver are melted together, the addition 
 of Iron will abforb all the Tin, and the Tin 
 only. Hence we are furnifhed with a me- 
 thod of purifying Silver from Tin, and con- 
 fequently of preventing the inconveniencies 
 which this metal conftantly occafions in 
 the refining of Silver by cupellation with 
 Lead. 
 
 {d) Tin and Arfenic.'] Tin melted with 
 Arfenic falls in great part into a whitifh 
 calx : The part which remains uncalcined 
 proves very brittle, and appears of a white 
 colour and a fparkling plated texture, greatly 
 refembling Zinc. The Arfenic is very 
 ftrongly retained by the Tin, fo as fcarce to 
 be totally diffipable by any degree of fire: 
 
 Though the mixture be urged for a length 
 of time, with a very intenfe fire ; the Tin, 
 afterwards recovered by fufion with inflam- 
 mable fluxes, difcovers, by its appearance, 
 by its brittlenefs, and by its augmentation of 
 weight, that it ftill holds a confiderable por- 
 tion of the Arfenic. Hence, as the com- 
 mon Tin ores abound with Arfenic, the 
 common Tin is found alfo upon experiment 
 
 to participate of that mineral Henckel 
 
 dilcovered a method of feparating a£tual 
 Arfenic from Tin; namely by flowly dif- 
 folvir.g the Tin in eight times its quantity 
 of an Aqua regia made with Sal ammoniac, 
 and fetting the folution to evaporate in a 
 gentle warmth : The Arfenic begins to con- 
 crete whilft the liquor continues hot, and 
 more plentifully on its growing cold, into 
 white cryftals. Mr. Marggraf, in the Ber- 
 lin Memoirs for the year 1747, has given a 
 more particular account of this procei's : He 
 obferves that the white fediment which at 
 firft feparates during the diflolution, is 
 chiefly arfenical: That Malacca Tin, which 
 
 is 
 
Metallic Bodies. i 
 
 Tin diflblves in all the mineral adds. For its difTolution in the vitriolic, it T i 
 requires the acid to be highly concentrated, and affifted by a boiling heat : u— ^ 
 The inflammable principle of the Tin, extricated during the diffolution, unites 
 with a part of the acid into a true Sulphur ; which iublimes, in its proper aci( ^ s 
 form, into the neck of the retort. 
 
 The nitrous acid ads upon Tin much more eafily : To obtain a perfect fo- 
 lution, the metal mult be added by very little at a time, and all heat avoided: 
 
 If much of the Tin is put in at once, it will only be corroded into a white 
 powder, or reduced into a thick gelatinous fubftance ; and if the folution 
 when made, be confiderably heated, the diffolved Tin will feparate again in 
 the like forms of a powder or gelly. 
 
 The marine acid has thegreateft affinity with Tin of all the acids, but does 
 not diflolve it without heat : It forfakes Mercury to unite with Tin, and when 
 thus combined with it, volatilifes a confiderable portion of the metal : A 
 ffrong fmoking fpirit diftils,. which if diluted with water, grows milky and 
 depofites the Tin. This fpirit, commonly diftinguifhed by the name of its in- 
 ventor Caflius, is prepared, by amalgamating three parts of Tin with five of 
 Mercury, grinding the amalgam with eight parts of Mercury fublimate, and 
 diftilling the mixture in a retort : The refiduum of this operation, treated 
 with Nitre, is the fudoriferum maximum of Faber, a title which it does not 
 very properly deferve. Some affirm, that a fmoking fpirit may be obtained 
 by putting Tin into butter of Antimony ; but this does not fucceed. 
 
 Aqua regia, or a mixture of the nitrous and marine acids, diflblves Tim 
 more perfectly than the one, and more readily than the other : When the ni- 
 
 trous has let the Tin fall in form of a white powder, if a little of the marine 
 be added,, and a moderate heat applied, the Precipitate will be taken up again- 
 and kept diffolved. An ounce oi Spirit of Sea-falt, mixed with only a fcruple 
 of Spirit of Nitre, diffolved Tin perfedly : But upon inverting the proporti- 
 
 ons, and taking a fcruple of the marine to an ounce of the nitrous acid, the 
 mixture, with four fcruples or four and a half of Tin, became thick like pap : 
 
 Some more of the marine acid being gradually added, the whole was diffolved: 
 into a clear liquor. In making the folution with thefe mixed acids, a final! 
 
 portion 
 
 cury: An amalgam of Tin being long tri- 
 turated with water, and the powder which 
 was wafhed off committed to fublimation, 
 a little Mercury came over, and bright arfe- 
 nical flowers arofe into the neck of the 
 retort. — Thefe curious experiments are here 
 inferted entirely upon the credit of the 
 authors. 
 
 Common Tin makes a crackling noife in 
 bending : This is commonly fuppofed to be 
 an effential property of pure Tin, but poffi- 
 bly it may belong only to fuch as is arfeni- 
 cated ; for thofe operations by which Arfenie 
 is faid to be feparated, deprive it of its 
 noife. 
 
 Ss accounted one of the pureft forts, yielded 
 no lefs than one fourth its weight of arfeni- 
 cal cryftals ; that fome forts yielded more ; 
 but that Tin extracted from a particular ore 
 which held no Arfenie, afforded none. That 
 the cryftals were truly arfenical, appeared 
 from their being totally volatile ; from their 
 fubliming (a little fixed alcaline Salt being 
 added to abforb the acid) into a colourlefs 
 pellucid concrete; from the Sublimate, laid 
 on a heated copper-plate, exhaling in fumes 
 of a garlic fmell ; from its ftaining the Cop- 
 per white ; and from its forming with Sul- 
 phur a compound fimilar to the yellow or 
 fulphurated Arfenie. He found that the 
 Arfenie was feparable alfoby means of Mer^ 
 
88 
 
 T I N. 
 
 Foils for Spe- 
 cula. 
 
 Aurum Mo- 
 faicum. 
 
 White ena- 
 mels, ,&c. 
 
 Cofmetic pre- 
 parations. 
 
 Ruby Glafs. 
 
 Medical hif- 
 tory. 
 
 Metallic Bodies. 
 
 portion of blackifh matter commonly feparates, and falls to the bot- 
 tom (e). 
 
 Vegetable acids, as diftilied Vinegar, do not diffolve any fenfible quantity 
 ■ of Tin : And hence I have been led to fufpedt that thofe who order a Salt to be 
 made from Tin by diftilied Vinegar, as ail the chemifts do, have been im- 
 pofed on by taking Tin alloyed with Lead ; and that inftead of a Salt of Tin, 
 they obtained no other than a Sugar of Lead. Pure Tin I have digefted. 
 boiled, and treated in many different ways with Vinegar; and the fame expe- 
 riments I have repeated with pure calx of Tin, which fome prefer, for this 
 ule, to the crude metal : But I never could obtain any thing faline, except an 
 unftuous kind of extract; and the Tin employed retained its original weight — 
 This metal is corroded by fixed alcaline Salts, whether melted along with 
 them, or boiled in a folution of them. 
 
 Tin amalgamated with Mercury is ufed as a foil for looking-glaffes, &c . — 
 The Amalgam mixed with Sulphur and Sal ammoniac, and fet to fublime, 
 yields a fparkling Gold-coloured fubftance, called Aurum Mofaicum , ufed in 
 England as a pigment: This preparation is commonly made from Quickfilver 
 and Tin of each two parts, amalgamated together, and then thoroughly 
 mixed with Sulphur and Sal ammoniac of each one part and a half: After fubli- 
 
 mation, th t Aurum remains at the bottom Calx of Tin is employed for 
 
 polifhing Glafs, Steel, &c. and makes the bafis of the white glazing cf earthen- 
 ware, and the white enamels : A portion of Lead is commonly mixed with 
 
 the Tin, that metal remarkably promoting its calcination : The compound 
 calx is called Putty. Tin may be ftill more expeditioufly calcined, by means 
 of Nitre or of common Salt : When the laft is ufed, the metal in fufion muft 
 be kept continually ftirring ; and in either cafe, the calx muft be well edulco- 
 rated with water —In the detonation of Tin with Nitre, white flowers arife, 
 
 which, colledted in aludels, have been employed by fome as a cofmetic: Ma- 
 gifteries or precipitates of the metal have been ufed alfo in the fame intention. 
 Le Mort relates, that a Salt is obtainable, by diftilied Vinegar, much more 
 eafily from the flowers, than from Tin in fubftance or its calx : But I have 
 
 never been able to obtain this Salt from thole any more than from thefe— 
 
 The folution of Tin in Aqua regia is ufed as a precipitant for Gold; and the 
 golden calx thrown down by it, for making the ruby Glafs ; an account of 
 which may be feen in Kunckel’s Laboratorium. See Gold. 
 
 Tin has been fuppofed to pofiefs confiderable medicinal virtues ; and even 
 Boerhaave is greatly prejudiced in its favour: He fays the Calx which preci- 
 pitates fpontaneoufly from its folution, is of Angular efficacy in hypochondri- 
 cal and hyfterical fuffocations. To fuch a character, this metal has no pre- 
 tence ; nor is the internal ufe of any of its preparations advifable. 
 
 Thers 
 
 (e) Solution of Pin.} The folution is fome- 
 times colourlefs, fometimes of a bluiih, and 
 fometimes of a bright yellow colour, ac- 
 cording to different circumftances in the 
 procefs. Mixed with red infufions or de- 
 coctions of animal or vegetable fubftances, 
 it greatly improves their colour : The dull 
 
 red of Cochineal is heightened, by a flight 
 addition of this liquor, intofcarlet; that of 
 Brazil wood into a lovely crimfon. The 
 folution of pure Tin fcarcely exhibits any 
 appearance of cryftals ; and if infpiffated to 
 drynefs, deliquiates in the air. 
 
Metallic Bodies, 
 
 There are two preparations of it ftill met with at times in the (hops, though T i 
 they little deierve a place there *, namely, th t antihefficum Poterii, and bezoaT* v 
 dicum joviale. The antihe&ic is made from equal parts of Tin and Regulus of 
 Antimony, melted together, then pulverifed, mixed with twice or thrice 
 their quantity of powdered Nitre, inje&ed into a red-hot crucible, and after 
 the deflagration, edulcorated and dried. The bezoardic differs from this only 
 in the manner of preparation •, the mixture of Regulus of Antimony and Tin 
 being reduced to a calx, not by detonation with Nitre, but by folution in acids, 
 after the fame manner as the bezoardicum miner ale . 
 
 The largeft quantities of Tin are met with in England, particularly in the Natu j 
 county of Cornwall. There is fome alfo in Bohemia and Saxony, and a little t 0 ry« 
 in the Eaft-lndies: But in other countries, it is rare to find fo much as to be 
 worth the trouble of extracting. Britain is fuppofed to have received its name 
 from its abounding with this metal ; Tin being called in the Syriac; and Chal- 
 daic languages Bragmanack, that is the kingdom of Jupiter ; whence are de- 
 duced, Bratman , Britman , Britannia. The ores of Tin are, (i .) Zinngraupen* 
 or cryftalline mafies, commonly of a polilhed furface, fometimes of a dark 
 brown, or violet colour, but chiefly blackifh : Thefe are the richeft of the Tin 
 ores. (2.) Zwitter , or cryftalline concretions refembling the foregoing, but of 
 a yellowifh or rufty colour, and lefs rich. (3.) Zinn-Jtein, Tin-ftone, much 
 poorer in Tin, and intermixed with a much larger proportion of ftony 
 and other mineral matters. (4.) Tin ore participating of Iron, called by 
 the miners Wolfram (/)- — -Allays of Tin ore are made, in the common man- 
 ner, with black flux. In the large way, the richer ores are barely melted 
 down among the fuel ; the poorer are previoufly ftamped and wafhed. 
 
 The Englifti and Malacca Tin are much purer than the Saxon, Bohemian, 
 or fuch as is prepared in any other country ; but they are very rarely to be 
 met with, at leaft in their pure ftate. In Holland, every Tin-founder has 
 Englifh ftamps ; and whatever his Tin be, the inlcription Block Tin makes it 
 pafs for Englifh. The Englilh Tin is never worked, in England itfelf, with- 
 out addition: All the wrought Tin imported from thence, we may be fure has 
 an admixture of fome other metal: The unwrought may be looked upon as 
 unalloyed. 
 
 The fubftances mixed with Tin are various; and every workman keeps his ., 
 mixture a fecret: Some are greatly fuperior to others : I remember fome per- 1 ew tr * 
 fons in England, not above three, whofe Pewter was hard and fonorous, and 
 almoft of a Silver whitenefs. In England, I rarely found any Lead in Pewter, 
 though we [in Germany] employ it in a large proportion : The Englifh feem 
 to avoid that metal, and very juftly; as it injures the found and the colour of 
 the Tin, and renders the veflels made from it apt to communicate dangerous 
 
 qualities 
 
 (f) Tin ore .] Tin is rarely or never found 
 native in the earth. Its ores are generally 
 met with in fmall mafies, feldom exceeding 
 two or three ounces in weight, intermingled 
 with a large proportion of earthy matter. 
 They are of an angular figure, moderately 
 
 hard, and remarkably heavy : The richer 
 forts are heavier than pure Tin itfelf. Their 
 colour is moft commonly brown or blackifh : 
 Sometimes, but very rarely, they arc white 
 and femitranfparent. 
 
 N 
 
9 ° 
 
 Metallic Bodies. 
 
 T i w. qualities to any kind of add liquors or foods. The compofition of the more 
 e deemed kinds of Pewter is worthy of a chymical enquiry : Without knowing 
 their compofition, the workman can never imitate them; and that can be de- 
 termined only by chymical experiments, unlefs chance fhould make the difco- 
 very. The principal fubftances made ufe of are, martial Regulus of Anti- 
 mony, Zinc, Bifmuth, Copper, Iron, Princes-metal : Each of thefe, or two 
 or three of them mixed together, make the Tin hard and fonorous, and of a 
 whitenefs approaching to that of Silver; but much depends on the proportion : 
 Of feveral of them, two or three pounds are fufficient for an hundred weight 
 of Tin. The Dutch put a whole pound of l.ead to ten pounds'^ Tin. 
 
 The workmen have two methods of diftinguilhing the admixtures of Lead 
 with Tin, and judging of the quantity of Lead. The firft is by biting into it 
 with the teeth: Pure Tin makes a crackling noife, and the more Lead it 
 
 holds, the lefs it crackles. The other is, by caking a bail of pure Tin ; and 
 another of the Tin to be examined, in the fame mould : The more this laft bul- 
 let exceeds that of the pure Tin in weight, the more Lead it contains ( g ). 
 Lead may be difeovered alfo by vegetable acids, as diftilled Vinegar, Le- 
 mon-juice, &c. which diffolve Lead, and have fcarcely any a<5tion on pure 
 Tin. 
 
 (g-) Examination of the purity of Tin hy 
 weight.'] Dr. Brandt has given a paper in the 
 Swedifh Tranfactions (1744) proving, from 
 experiment, that the finenefs of worked 
 Tin may be allayed with great accuracy 
 from its weight, without melting, or in- 
 juring the figure of the veffel. He found 
 that a piece of fine Tin, weighing in the 
 air 531 grains, loft in water 75I: That 
 a piece of four-ftamped Tin, of the 
 fame weight (compofed, according to the 
 royal ordonnance, of 97 parts of fine Tin 
 and 3 of Lead) loft in water 72! : That 
 the fame weight of thrice-ftamped Tin (in 
 which the proportions are 83 of fine Tin 
 to 17 of Lead) loft in water 68 \ : And 
 that the fame quantity of double-ftamped 
 Tin (confiding of 66| Tin and 23! Lead) 
 loft 64. Upon thefe principles, when 
 wrought Tin was brought to be affayed, 
 inftead of taking off any part of the veffels 
 
 for an experiment by fufion, he weighed 
 them entire in air and in water : When 
 the lofs in water was proportion ably lefs 
 than that of the ftandard bar, they were 
 judged to contain too much Lead, and a 
 further examination always (hewed that 
 they did. He obferves that this method 
 has one great advantage in common bufi- 
 nefs, that large utenfils are affayed to a 
 greater degree of nicety than fmall fpeci- 
 mens ; the accuracy depending on the 
 fenfibility of the balance, and large ba- 
 lances being more fenfible, or turning with 
 a lefs weight in proportion to the whole 
 quantity they are loaded with, than fmall 
 ones : A good affay balance did not turn 
 with lefs than the 7000th part of the 
 weight upon each arm ; whilft an ordinary 
 large balance, which bore on each arm 
 800 pounds, turned, when loaded, with 
 the 25600th’ part of that weight. 
 
 CLASS 
 
E T A L L I C 
 
 O D I E S* 
 
 CLASS III. Semimetals. 
 
 Metallic bodies not bearing the hammer ; volatile in the fire . 
 
 I. MERCURY or Q^U ICKSILVER, 
 
 M ERCURY is a fluid metallic fubftance, not moiftening the hands ; Mercury. 
 
 perfedly opakej of a bright filver colour, refembling Lead or Tin 
 when melted ; entirely void of tafte and fmell ; extremely diviftble(^) ; not Its S® n ® ral 
 congealable in the greateft degree of cold hitherto known (i). prop ’ 1 ” 1 
 
 It is the moft ponderous of all fluids, and of all known bodies except Gold [and 
 Piatina:] Its gravity is to that of water nearly as 14 to 1 5 a cubic foot of Quick- 
 filver weighing 947 pounds, whilft a cubic foot of water weighs but 70 : It is 
 found to be heavier in winter than in fummer, in the proportion of eleven 
 ounces thirty-two grains, to eleven ounces feven grains. In confequence of 
 its great denfity, it is of all fluids the coldeft to the touch : The hand cannot 
 be kept one quarter of an hour in a quantity of Quickfilver with fafety. Of 
 all fluids likewife it grows hotteft (not really, but apparently) from the appli- 
 cation of an equal external heat. 
 
 In a heat below ignition, it totally exhales in extremely thin, fubtile, pe- 
 netrating fumes, which condenfe into running Mercury again : The admiflion. 
 of air, which changes the fumes of the other femimetals into a powdery calx, 
 has not that e fted upon thofe of Quickfilver (k). 
 
 (b) Mercury , extremely diviftble.] In fmall 
 drops, it aflumes a fpherical figure. The 
 globules divide, from the flighted touch, 
 into numerous fmaller ones, each further 
 divifible by the fame means : The minuteft 
 that can be diftinguifhed, by the naked eye, 
 or microfcopes, appear perfect fpecula, very 
 vividly reflecting the images of neighbour- 
 ing objects. They lofe their fphericity if 
 placed upon certain metals, particularly 
 Gold; on which the mercurial globules 
 fpread themielves, like water upon moift 
 bodies, and thus difeover their great affinity 
 with it. This fluid may be ftrained, by mode« 
 rate prefiure, through the pores of leather ; 
 and thus freed fromduft or other like impu- 
 rities that may be accidentally blended 
 with it. 
 
 (/) Not congealable.'] Though it never has 
 been known to become folid from cold, it 
 has fometimes been obferved, in very in- 
 tenfe colds, produced by artificial mix- 
 tures, to lofe confiderably of its fluidity. 
 There is an inftance, in the Asia natura 
 curioforum , tom. vii. of its acquiring the con- 
 fiftence of a foft Amalgqpi, or of a mixture 
 
 N 
 
 of Mercury with one fourth its weight of 
 Lead or Tin. 
 
 [k] Change— into calx.] This femimeta! is 
 neverthelefs convertible, if not into a true 
 calx, yet into the appearance of one, by a 
 long continuance of a heat juft not ftrong 
 enough to dilfipate it. By degrees it changes 
 into a powder, at firft afh-coloured, after- 
 wards yellow, at length of a bright red co- 
 lour, and of an acrid tafte This proves 
 
 lefs volatile in the fire, than the Mercury in 
 its fluid ftate : It fupports, for a time, even 
 a degree of red heat. In the focus of a 
 burning-glafs, it is faid, if expofed upon a 
 tile, to vitrify, on a piece of charcoal to re- 
 vive into running Mercury, before it ex- 
 hales. Evaporated by common fire, it 
 leaves a fmall portion of a light brown pow- 
 der; which, as Boerhaave relates (in the 
 Philofophical Tranfactions) bore a blaft 
 heat, fwelled into a fpongy mafs, formed 
 with Borax a friable vitreous fubftance, but 
 in cupellation vanifhed. 
 
 By a heat no greater than that of the hu- 
 man body, or even of boiling water, though 
 continued for fome years, only a fmall por- 
 2 tipn 
 
Mercury. 
 
 tion of the Mercury is converted into pow- 
 der : The powder thus obtained appears of 
 a dark greyifh or black colour. Conftant 
 triture or agitation produce a change fimilar 
 to that effefted by this low degree of heat, 
 and in a far fhorter time. 
 
 As Mercury affumes thefe adventitious 
 forms, without communication with the air, 
 or the lofs of any of its parts, it recovers its 
 own without addition : Both the red and the 
 black powders, expofed barely to a lire fuffi- 
 cientto elevate them, return into fluid Mer- 
 cury again. The red powder has been re- 
 vived into Quickfilver by Amply grinding it 
 in a glafs mortar. 
 
 Repetitions of thefe operations occafion 
 no permanent change in the Quickfilver. 
 Boerhaave had the patience to diftil Mer- 
 cury five hundred and eleven times fuccef- 
 fively ; to keep it in conftant agitation for 
 many months ; to digeft it for upwards of 
 fifteen years together, in low degrees of 
 heat, both in open and in clofe velfels, by 
 itfelf and in conjunction with other metallic 
 fubftances ; and received from all his la- 
 bours only this refult, that Mercury is not by 
 any of thofe means to be changed. It were 
 to be wifhed, that this indefatigable enquirer 
 had purfued procefles more agreeable to the 
 general doftrine of thofe who pretend to 
 have changed it : It is not by low degrees 
 •of heat, but by the ftrongeft it can fuftain, 
 that the philofophers by fire think to lay 
 fetters upon this fugitive metal. 
 
 Dr. Brandt amalgamated fine Gold with 
 a large proportion of Quickfiver, and having 
 ftrained off the fuperfluous Mercury, di- 
 gefted the Amalgam, in a clofe ftopt veil'd, 
 for two months, with fuch a heat, that a 
 part of the Quickfilver fublimed into the 
 neck of the Glafs. The matter being then 
 ground with twice its weight of Sulphur, 
 and urged with a gradual fire in a crucible, 
 a fpongy calx remained, which being melted 
 with Borax, and afterwards kept in fufion 
 by itfelf for half an hour in a very violent 
 fire, ftill retained fo much of the Quick- 
 filver, as to prove brittle under the hammer, 
 and appear internally of a leaden hue. The 
 metal being amalgamated with frefh Mer- 
 cury, the Amalgam again ground with Sul- 
 phur, and expofed to an intenfe fire, a 
 ipongy calx remained as before. — — —This 
 calx being digefted in two or three frefh 
 parcels or Aqua regia, a fmall portion of 
 
 whitifh matter remained at laft undiiTolved. 
 The paper which covered the cylindrical 
 Glafs wherein the digeftion was performed, 
 contracted from the vapours a deep green 
 circular fpot in the middle, with a fmaller 
 red one at the fide ; whereas the Aqua regis 
 digefted in the fame manner by itfelf, or 
 with Gold, or with Mercury, gave no ftain. 
 The firft folution, on the addition of Oil of 
 Tartar per deliquium, grew red as blood ; 
 on Handing, it depofited, firft a little yel- 
 low calx like Aurum Fulminans, afterwards 
 a bright matter like fine Gold, and at laft 
 a paler Precipitate inclining to green; its own 
 deep red colour and tranfparency continuing 
 unchanged : Being now committed to diftil— 
 lation, a colourlefs liquor arofe; and the 
 refiduum, perfectly exficcated, yielded on 
 edulcoration a yellow calx of Gold, which 
 the alcalineLixivium had been unable to pre- 
 cipitate. The fecond folution turned green 
 on the admixture of the alcaline liquor, and 
 let fall a white Precipitate, which edulco- 
 rated, looked black and brown The 
 
 feveral precipitates were calcined with twice 
 their weight of Sulphur, and then melted, 
 with four times their weight of Flint and 
 twelve ofPot-afh, in a fire vehementLy ex- 
 cited by bellows. The fcoria appeared of 
 a golden colour, which on pulverization 
 and edulcoration vanifhed. At the bottom 
 was a Regulus, which looked bright like the 
 pureft Gold, but was not perfectly malle- 
 able : Broke, it appeared internally white, 
 and the white part amounted to at leaft one 
 third its bulk ► Befides this lump of metal, 
 there were feveral fmaller ones, white like 
 Silver, and foft as Lead This remark- 
 
 able experiment was made in the Royal 
 Elaboratory at, Holm, and communicated in 
 the Affa liter aria fuecics for the year 173,1. 
 The author concludes from it, that a por- 
 tion of Quickfilver, and a very confiderable 
 one, is detained and fixed by digeftion with 
 Gold, fo as not to be diftipable by the moil 
 intenfe fires. He exprefsly mentions the 
 Gold, made ufe of, being highly refined; 
 and though he does not inform us what the 
 Mercury was, it feems hard to fufpeH that this 
 accurate and expert chymift fhould employ, 
 for fuch a curious purpofe, Mercury whofe 
 purity from Lead, or the other fubftances 
 with which it is fometimes fophifliqated, he 
 had not duly examined. 
 
 Some have pretended to convert Quick- 
 filver 
 
Metallic Bodies. 
 
 93 
 
 It dilTolves in all the mineral acids, but with different degrees of facility ; Mercury, 
 and proves itfelf a menffruum for fundry metallic bodies (/). It has the 
 greateft affinity with, Gold adhering to and difl'olving that metal the m °ftfo^eu]s Un 
 
 readily 
 
 filver into a limpid water, capable of dif- 
 folving metals, and producing extraordinary 
 effects on them. This is attempted by ex- 
 pofing the Mercury to the fudden adtion of 
 a ftrong fire : A tall iron vefiel, furnifhed 
 with a capacious head, aludels, and a reci- 
 pient, is heated to a white heat, and the 
 Quickfilver injedted, by a very fmall quan- 
 tity at a time, through an aperture made 
 for that purpofe near the top. Kunckel has 
 fhewn the fallacy of this procefs ; that the 
 liquor fometimes colledled in the receiver is 
 no other than a merely aqueous one, acci- 
 dentally contained in the Mercury or forced 
 out from the luting, in no refpect different 
 from common water. I have oftener than 
 once repeated the experiment with pure dry 
 Mercury, without being able to obtain the 
 leaft appearance of any moifture. 
 
 (/) A menjlruum for metals.'] There are 
 three metallic bodies, which Mercury 
 does not diffolve or unite with ; Iron, 
 Arfenic, and the femimetal called Nickel. 
 It will in fome cafes abforb metals, par- 
 ticularly Gold and Silver, from their 
 folutions both in acid and in alcaline 
 liquors ; but does not add upon any metal 
 when combined with Sulphur, nor on preci- 
 pitates made by alcalies, nor on calces pre- 
 pared by fire. Whatever metal it is united 
 with, it conftantly preferves its own white 
 colour. 
 
 Saline liquors diffolve only a certain quan- 
 tity of metals ; which they carry with them 
 through all the ftrainers that the liquor is 
 capable of paffing by itfelf. Mercury unites 
 with any proportions, forming, with diffe- 
 rent quantities, amalgams of different de- 
 grees of confiftence: From the fluid ones, 
 greateft part of the Quickfilver may be fe- 
 parated by colature. Bifmuth is the only 
 metallic body, which is fo far attenuated by 
 Mercury, as to pafs through leather with it 
 in any confiderable quantity ; and Lead is 
 the only one, to which Bifmuth communi- 
 cates that property in any confiderable de- 
 gree. 
 
 Bilmuth promotes the a&ion of Mercury 
 
 upon Lead in a remarkable manner. Quick- 
 filver impregnated with one fourth, one 
 eighth, one twelfth its weight of Bifmuth, 
 diffolves maffes of Lead, in a gentle warmth; 
 without the agitation, or triture, or commi- 
 nution, or melting heat, neceffary for unit- 
 ing Lead with pure Mercury. Thefe ex- 
 periments I made, fome years ago, on a 
 report, that an eminent French furgeon had 
 dilcovered a fafe menftruum for diffolving 
 pieces of Lead lodged in cavities of the hu- 
 man body. 
 
 On triturating or digefting amalgams for 
 a length of time, a blackifh or dufky co- 
 loured powder arifes to the furface, and may 
 be readily walhed off by water. Some of 
 the chymifts have imagined, that the amal- 
 gamated metal is here refolved into its con- 
 ftituent parts. But pure Mercury, as we 
 have already feen, is convertible by itfelf, 
 on the fame treatment, into a fimilar pow- 
 der ; and the metallic particles, united in 
 this procefs with the mercurial powder, are 
 found to be no other than the metal in 
 its entire fubftance. Some metals feparate 
 much more ftowly and difficultly than 
 others ; Gold and Silver the moft fo. 
 
 It is faid, that the Quickfilver, in thefe 
 powders, proves more volatile than in its 
 common fluid ftate ; that if the powder, 
 which feparates from an amalgam of Lead, 
 be committed to diftillatiori with Vinegar in 
 a tall vefiel, the Mercury will arife before 
 the Vinegar boils ; that by a like artifice, 
 Quickfilver may be made to diftil even in a 
 lefs degree of heat than that of the human 
 body. This I relate upon the authority of 
 Boerhaave ; having never been able myfelf, 
 though the trials were often repeated, to 
 fucceed. 
 
 On expofmg amalgams to a fire gradually 
 raifed to ignition, the Mercury freely ex- 
 hales, leaving the metal behind in form of 
 a very fubtile powder. A fmall portion of 
 fome of the metals generally arifes along 
 with the Quickfilver. Thus Mercury di- 
 ftilled from Lead, Bifmuth or Tin, appears 
 lefs bright than before, ftains paper black, 
 fometimes exhibits a fkin upon the furface, 
 
 and'. 
 
M" 
 
 E T A L L I C 
 
 Bodies. 
 
 lets eafily with Lead ; ftll! 
 
 How 
 
 kept. 
 
 94 
 
 Mercury, readily of all. It unites eafily alfo with Silver; 
 
 ' iefs fo with Tin; very difficultly with Copper; mod difficultly of all with 
 Iron, to which itfeems to have an infuperable repugnance. It does not eafily 
 take up Bifmuth or Regulus of Antimony, unlefs they are previoufly mingled 
 with other metals, or difpofed to unite with it by particular managements : 
 After it has been combined with either of thefe, it throws them out again upon 
 digeftion : Bifmuth neverthelefs difpofes fome other metals, particularly Lead, 
 to fuch an intimate union with the Mercury, as to pafs along with it through 
 the pores of leather. Quickfilver mingles alfo with various faline fubftances, 
 and with Sulphur ; with which laft it forms a black mafs called athiops , which 
 changes, on fublimation, into a red one called Cinnabar, 
 to be The gravity and divifibility of Mercury renders great precaution neceffary 
 in regard to the veffels in which any confiderable quantities are exported or 
 kept; the fmalleil hole or crack permitting it to efcape. Metalline veffels arc 
 improper; and glafsor earthen ones are too liable to break. The veffels com- 
 monly made ufe of are, either compact wooden ones ; or ftrong thick leather, 
 in which all the Spanifii Mercury is brought from America ; or thick glafs 
 bottles, or turned wooden boxes, fecured in leather. 
 
 Methods of There are fundry methods mentioned in books forjudging of the goodnefs 
 judging of its 0 f Quickfilver; but they feem to be built upon vain conceits about theMer- 
 pmity* curies of metals. Some diredt the Quickfilver to be expofed to the fire, and 
 the colour of its fumes examined : Green or yellow fumes denote a folar, 
 bluifli ones a lunar, and reddifh brown a venereal Mercury : A jovial Mer- 
 cury is diftinguiffied by a whitifh colour of the fumes, a faturnine by an afh- 
 grey colour, and a martial by a dark yellow. Others, dillregarding the fumes, 
 attend only to the fpot which remains upon evaporating fome of the Quick- 
 filver in a Silver fpoon : If the fpot is yellow or white, the Mercury is held to 
 be good, the yellow colour being fuppofed to proceed from Gold, and the 
 white from Silver : A brown or black fpot on the other hand is a mark that 
 the Mercury is of a bad kind ; thele colours proceeding from Copper or fome 
 of the baler metals. 
 
 We need not however be folicitous about the colour either of the fumes or 
 the refiduum : If any powdery or any adlual matter at all is left, we may be 
 fure that the Quickfilver is adulterated, moft probably with Lead ; a confider- 
 able portion of that metal being mifcible with Mercury, by the mediation of 
 Bifmuth, not only without deftroying its fluidity, but fo as to pafs with it, by 
 preffure, through leather. It is not needful to fuffer the Mercury to exhale 
 
 in 
 
 and does not run freely or into round glo- 
 bules. Boyle relates, that he has obferved 
 the weight of the Mercury fenfibly increafed 
 by diftiilation from Lead, and this when 
 only a moderate fire was made ufe of. 
 
 Mercury amalgamated with ftellated Re- 
 gulus of Antimony, digefted for fome hours 
 and then diftilled off, is faid to become, by 
 a few repetitions of theprocefs, more pon- 
 derous and more active ; the animated or 
 philofophic Mercuries of fome of the alchy- 
 snifts, are fuppofed to have been Quickfilver 
 
 thus prepared. By the fame or by fimilar 
 proceffes feem to have been obtained the 
 curious Mercuries which Boyle declares he 
 was in poffeffion of and made himfelf ; 
 which “ were confiderably heavier in fpecie 
 
 “ than common Quickfilver diffolved 
 
 “ Gold more readily —grew hot with Gold, 
 “ fo as to be offenfive to the hand — and 
 “ elevated Gold in diftiilation.” See his 
 producibility of chymical principles, p. 209. 
 &c. and the Philofophical Tranfaftions, 
 N° 122. 
 
Metallic Bodies, 95 
 
 in the air, in order to difcoverits adulteration ; it may be all faved, by diftil- Mercury. 
 ling it in a retort: If it totally arifes, without leaving any refiduum, we may 
 be fatisfted of its purity. The abufe may be detefted alfo ftill more commodi- 
 oufly and expeditioufly, without a retort, or a Silver lpoon, or a crucible, or 
 fire: If a little of the Quickfilver be diflolved in Aqua fortis, a white precipi- 
 tation will prefently betray the Lead. The external marks of its purity are its 
 whitenefs and brightnefs, and the facility of its running when a little is dropt 
 on a table, The marks of its impurity are, its appearing dully, contract- 
 ing afkin on the furface, running flowly, and leaving a droffy matter behind. 
 
 There are different methods of purifying Quickfilver; as draining through Purification., 
 leather; trituration or ablution with Vinegar, with Vinegar and Salt, with 
 Sope-leys, with rectified Spirit of Wine, and with Aqua fortis ; and diflilla- 
 tion, either without addition, or with alcaline Salts, Quicklime, or Iron filings. 
 
 When Quickfilver is only fuperficially mixed with dull or earthy powders, 
 draining through leather is fufficient for its purification: If any foulnefs dill 
 remains. Spirit of Wine will, wafh it off : Unctuous or oily impurities require 
 ablution with Sope-leys. Lead and Bifmuth are molt effectually feparated by 
 making the Mercury into an a: l hi ops with a fufficient quantity of Sulphur, and 
 reviving it again from the athiops by diftillation with twice its quantity of 
 Quicklime, alcaline Salt or Iron filings : The Mercury alone will didill, and 
 leave all its impurities behind: Sulphureous, antimonial, and other like ad- 
 mixtures are to be feparated by the fame means. The purification by Aqua 
 fortis is performed by taking only a fmall quantity of the acid to a large one 
 of Mercury ; grinding them diligently together, and then waffiing the Quick.- 
 filver with water. When Mercury is combined with Sulphur into Cinnabar,, 
 the revivification of it does not well fucceed with alcaline Saks ; by fixed alca- 
 lies, the Sulphur is very difficultly, and not perfectly, ablorbed ; to volatile 
 alcalies, it does not yield at all: On the other hand it is obfervabie, that me- 
 tallic bodies, as Iron, Lead, Tin, Regulus of Antimony, readily detain the 
 Sulphur in diftillation, and fuffer the Mercury to arife pure. 
 
 The larged: quantities of Mercury are employed for metallurgical operations : Ufes,. 
 
 Gold and Silver are extracted, in the Spaniffi Wed-Indies, from their ores or 
 matrices, by amalgamation with Mercury ; and both metals are recovered by 
 the fame means, when blended in minute particles with earthy matters, as in 
 filing or working them. Amalgamated with Tin, it makes the foil for look- 
 ing-glaffes, and refledling balls. It is ufed alfo for gilding on Silver, for ana- 
 tomical injections, for weather- glaffes, and fundry other purpofes. In vacuo, 
 it appears luminous, and is then called the mercurial Phofphorus. 
 
 Quickfilver, confidered as a medicine, is a fpecific againft the venereal dif- Medical hifr 
 eafe, worms, lice, and all kinds of infeCts : The venereal diftemper is not per- tor y* 
 haps to be radically cured without it, but againft infects there are other reme- 
 dies equally if not more effectual. It is commonly fuppofed to have, of itfelf, 
 no poifonous quality ; but it appears, from experience, manifedly prejudicial 
 to the nerves and the bones. Its ill effects are molt obfervabie in thofe, who 
 are expoled to its fumes; which fumes are no other than perfeCt Quickfilver,. 
 as any one may be convinced by receiving them on a piece of moift leather or 
 cloth, upon which they will reunite into little globules of Mercury. Molt 
 
 people: 
 
9^ Metallic Bodies, 
 
 Mercury, people admit a pernicious quality in the fumes, though they deny it to the 
 Quickfilver; not confidering that the fumes are only the Quickfilver itfelf, 
 divided but not altered by the heat. Even mercurial omtments applied exter- 
 nally have occafioned contractions of the limbs, corrofions of the bones, and 
 other dangerous confequences. How foon do the miners feel its ill effeds, 
 though they neither anoint with it, nor fwallow it, nor are expoled to the 
 fumes into which it is refolved by fire! they firft become paralytic, and fall 
 afterwards into a falivation : Their teeth drop out : Violent pains in the whole 
 body, particularly in the bones, and at length death, fucceed. It may be pro- 
 per to obferve, that the Spanilh phyficians treat thefe patients in a different 
 method from that purfued among us and in other countries : They expofe 
 them frequently for a confiderable length of time to the open air, and give in- 
 ternally nothing but abforbents. 
 
 Quickfilver is employed medicinally, in a great variety of forms; in its 
 crude ftate; diffolved in different menftrua ; fublimed with them ; precipitated 
 from them. Crude Quickfilver is ufed either by itfelf, or in compofition with 
 other fubftances : By itfelf, in large quantity, for forcing open inteftinal ob- 
 ftrudions: Combined with Sulphur, into athiops mineral \ with powdered An- 
 timony into an antimonial athiops ; with different unduous matters into ointments 
 and plajlers both for venereal complaints and cutaneous infeds; with gums 
 and gummy refins into venereal pills. The belt method of making theaethiops 
 mineral is, to put the flowers of Sulphur into an iron mortar over the fire, 
 till they begin to melt; then to remove the mortar from the fire, and fqueeze 
 in the Mercury through leather; and grind them well together with a 
 warm iron peftle. By this method they will unite more eafily, and more per- 
 
 fedtly, than by trituration without heat Some take Quickfilver, powdered 
 
 Antimony, Gum guaiacum, and make them into a mafs with extrad of li- 
 quorice. Du Moulin, an Englifh phyfician, abftained from all the mercurial 
 preparations made with Salts, and ufed only the following pills: Two ounces 
 of Quickfilver were killed with three ounces of Venice Turpentine, then mixed 
 with powdered Aloes, Scammony and Colocynth, of each two ounces, and a 
 dram of Oil of Cloves ; and the whole made into a mafs with a proper quan- 
 tity of Syrup of Buckthorn. Some grind the Quickfilver for a length of time 
 with Sugar, and diffolve it in water. Some boil Quickfilver alone in water, 
 and thus obtain a medicine againfl worms : If the diftilled waters of Saint- 
 johns-wort, Meadow-fweet, or Grafs-roots be made ufe of, the liquor is called 
 aqua hermetica. The Mercury, by this treatment, does not appear to lofe any 
 thing of its weight ; but the water is found to have different effeds from thofe 
 of plain water. 
 
 Chymical The chymical preparations of Mercury are very numerous, and moftof them 
 
 preparations, unfafe or unneceffary. Frederic Hoffman the elder juftly obferves, that he 
 who has two good preparations of Mercury needs no more : And in effed, if 
 we have but good Mercurius dulcis and Cinnabar for internal ufe, and corrofive 
 Sublimate and red Precipitate for external, all others are fuperfluous. Hel- 
 mont alledges, that fo long as Quickfilver can be revived, it is no fafe medi- 
 cine ; but if this was true, no mercurial medicine could be fafe. Mercury 
 eludes all our attempts to analyfe or deftroy it : Whatever fubftances it is 
 
 combined 
 
Metallic Bodies, 97 
 
 combined with, whatever operations it is fubmitted to, it ftill remains Mer- Mercury* 
 cury : We can transform it into a variety of fhapes, but the bare acftion of heat 
 or the feparation of the fubftances joined to it, conftantly reftores it again to 
 its own. Thofe who affirm Mercury to have been in certain operations irre- 
 ducibly deftroyed, feem to have been miffed by an opinion, ftill too common, 
 that the feveral fubftances employed in making a preparation, are retained in 
 the product. How many ftill believe, that Aqua fortis, diftilled from a mix- 
 ture of Vitriol and Nitre, contains the vitriolic as well as the nitrous acid ? 
 
 That corrofive Sublimate, made with Vitriol, Nitre, and Sea-falt, contains the 
 acids of the two firft as well as of the laft ? though it is certain, that the vi- 
 triolic acid in the one cafe, and both the vitriolic and nitrous in the other, re- 
 main at the bottom of the diftilling or fubliming veflel. In like manner But- 
 ter of Antimony has been fuppofed to contain the Mercury made ufe of in 
 making it, and a Precipitate from the Butter has been diftinguifhed by the 
 name of Alercurius vita: No Mercury is indeed reducible from thefe prepara- 
 tions, but if we examine the matter left in the retort, all the Mercury em- 
 ployed will be found the're. 
 
 Solution of Mercury is commonly made in Spirit of Nitre or Aqua fortis : Solution 
 A quantity of the acid, more or lefs in proportion to its ftrength, is poured 
 upon the Quickfilver, and a gentle warmth applied till the whole of the Mer- 
 cury is diftblved. If the folution is very ftrong of the Mercury, a part will 
 cryftallize upon the removal of the hear. Both the folution and the cryftals 
 
 are employed for other preparations Mercury is diftblved alfo in Oil of 
 
 Vitriol ; but for this purpole a confiderable heat is required. Boerhaave calls 
 this folution the ignis gehenna or infernalis of Paracelfus ^ and imagines, that 
 when concentrated, it is the aurum horizontale of Helmont. If the liquor be 
 abftradted to drynefs, a white mafs remains, which on the afTufion of water 
 afiumes a fine yellow colour, and when duly edulcorated is called turpethum 
 miner ale i or mercurius pracipitatus flavus ( m ). 
 
 The 
 
 [m] Menjlrua of Mercury.'] Aqua fortis, 
 of fuch a degree of ftrength as to diftolve 
 half its weight of Silver, diffolves with eafe 
 above equal its weight of Quickfilver, into 
 a limpid liquor, intenfely corrofive. The 
 folution infpiffated, or the cryftals, affume, 
 on being moderately calcined, a fparkling 
 
 red colour Oil of Vitriol, boiled upon 
 
 Mercury to drynefs, corrodes about an 
 equal weight or more, into a faline mafs 
 partially foluble in water. Kunckel ob- 
 serves, that by pouring on this white mafs 
 a very little water at a time, fo as not to 
 turn it yellow, nearly the whole will be 
 diffolved. A total folution may likewife be 
 obtained by repeating the codfion in frefh 
 
 Oil of Vitriol 1'he marine acid does not 
 
 adt upon Mercury, unlefs highly concen- 
 trated and refolved into fume ; in which 
 
 ftate it corrodes a large proportion into a 
 colourlefs cryftalline mafs, which according 
 to the quantity of acid proves either pellucid, 
 diftoluble in water, and extremely cauftic ; 
 
 or opake, indifloluble and infipid It 
 
 has the greateft affinity with the marine 
 acid, and the leaft with the nitrous. Silver 
 is the only metallic body befides, which is 
 precipitated from the nitrous by the vitriolic, 
 and from the vitriolic by the marine : And 
 hence Mercury may by this means be ef- 
 fectually purified from admixtures of all 
 other metals, though the procefs is too ope- 
 
 rofe for common ufes Alcaline Salts 
 
 precipitate Mercury from all acids. Fixed 
 alcahes, calcined with animal coals, if 
 added in a larger quantity than is fufficient 
 for the precipitation, rediiTolve what they 
 had before thrown down : Volatile alcalies 
 
 . have 
 
E'T A LL I C 
 
 Bodies. 
 
 Mercury. 
 
 CorroEve 
 
 Sublimate. 
 
 The mercurial Sublimates are of two kinds ; thofe made with the acid of 
 common Salt, and thofe with Sulphur. To the former belong corrofive Sub- 
 limate, Mercurius dulcis, and the mercurial Panacea ; the firft of which is the 
 
 bahs of the other two- Corrofive Sublimate is no other than cryftals of 
 
 Mercury made with the concentrated marine acid, by means of fublimation; 
 fume other fubifances being added, to facilitate the union of that acid with the 
 Mercury. For combining Quickfilver with the acid of Sea-falt, it isneceffary, 
 that either the Mercury itfelf be previouQy diffolved in the nitrous or vitriolic 
 acids, in which cafe the marine will attract it from both; or that the marine 
 acid be united with fome fixt body that may render it capable of bearing a con- 
 fiderable heat, as it naturally is in common Salt: If Mercury and common 
 Salt were mixed together and expofed to the fire, the Mercury would diftill by 
 itfelf; but if the nitrous or vitriolic adds are added, thefe extricate the marine, 
 which now corrodes the Mercury, and arifes along with it in form of a white 
 cryftalline mafs. There are many different methods of preparing this Subli- 
 mate, as (1.) from Mercury, common Salt, Nitre and Vitriol, (2.) from Mer- 
 cury, common Salt and Vitriol, (3.) from Mercury, common Salt and Spirit 
 of Nitre, (4.) from folution of Mercury in Aquafortis, and common Salt, 
 (5.) from folution of Mercury in Aqua fortis, and Spirit of Salt, or from the 
 white Precipitate, (6.) from Mercury, common Salt, Nitre and Oil of Vitriol, 
 (7.) from edulcorated Turpeth mineral and common Salt, (8.) from red Preci- 
 pitate, common Salt, and Oil of Vitriol, (9.) trom edulcorated Turpeth mine- 
 ral and Spirit of Sait, ( 10.) from Mercury, Sal ammoniac and Oil of Vi- 
 triol, &c. The fublimates obtained from all thefe mixtures may be taken in- 
 difcriminately for any common ufes; though in fome of the nicer experiments, 
 confiderable differences are obferved among them, efpecially betwixt thofe 
 made with or without Nitre or its acid, and more particularly where thefubli- 
 mation is repeated with this or that addition. 
 
 The common method of making fublimate, at Venice, London, and Am- 
 fterdam, where feveral hundred weight are fublimed at once in eight laro-e 
 glaffes placed in one furnace, is, according to Tachenius’s account, as follows. 
 Two hundred and eighty pounds of Quickfilver, four hundred pounds of 
 Vitriol calcined to rednefs, two hundred pounds of Nitre, the lame quantity 
 of common Salt, and fifty pounds of the Caput Mortuum remaining after a 
 former fublimation, or in wane of this, of the Caput Mortuum of Aquafortis, 
 making in all eleven hundred and thirty pounds, are well ground and mixed 
 together, and let to fublime in proper glaffes placed on warm afhes : The fire 
 is increafed by degrees, and continued for five days and nights. In the making 
 of fuch large quantities, fome little precautions are neceffary, which thofe con- 
 ilantly employed herein are beft acquainted with ; the principal are, the due 
 mixture of the ingredients, which in fome places is performed in the fame 
 manner as that of the ingredients for gunpowder ; that a helm and receiver be 
 
 adapted 
 
 have no fuch effeft— — -Vegetable acids do neral acids- It is faid, that when tritu- 
 not a£t in the leaf!: upon Mercury in its me- rated with Sugar and a fmall proportion of 
 tallic ftate ; but fparingly diffolve it when effential Oil, it diffolves in water; and that 
 reduced by lire into a powdery form, and it gives a violet tin&ure to pure effential 
 when precipitated by alcalies from the mi- Oils, particularly that of Juniper-berries. 
 
adapted to the fubli mi ng glafs, to fave a little fpirit which arifes ; that the fire be Mercury-. 
 not raifed too haftily ; that when the Sublimate begins to form, the afhes be J 
 
 removed from the fides of the glafs, or the glafs cautioufly lifted up a little 
 from the afhes •, and that the elaboratory have a good chimney, by which the 
 noxious fumes may freely pafs off. The quantities above-mentioned yield 
 commonly three hundred and fixty pounds of Sublimate, the two hundred and 
 eighty pounds of Mercury gaining eighty from the acid: So that Sublimate 
 confifts of about feven parts of Quickfilver, and two of marine acid The 
 makers of Sublimate in Trance, as I have obferved in my travels in that king- 
 dom, employ in one operation but twenty pounds of Mercury: They diffolve 
 the Mercury in Aqua fortis, evaporate the folution to drynefs, mix with the 
 dry matter twenty pounds of decrepitated Sea-falt and fixty pounds of calcined 
 Vitriol ; and then proceed to fubiimation. 
 
 This preparation is violently corrofive ; and poifonous in a high degree to 
 all animals. Solutions of it in water are employed externally for venereal and 
 other foul ulcers. It is mixed with Antimony for making the antimonial But- 
 ter and Cinnabar, with Tin for the Spiritus fumans caffii, &c. It is ufed al fo 
 in feme mechanic bufineffes, particularly by the goldfmitbs: Inje&ed on fome 
 forts of brittle Gold in fufion, it confumes the impurities, and renders the 
 metal malleable : See page 41. Some have affirmed that Sublimate is often 
 adulterated with Arfenic; and propofed its turning black with alcaline Lixivia 
 as a means of difeovering the abufe. But this adulteration is absolutely im- 
 practicable, Arfenic being incapable of arifing in fubiimation along with 
 Mercury fublimate. See Arfenic. If Sublimate indeed was fold in powder, 
 the adulteration might be praCtifed ; but we may be always certain that the 
 cryftalline cakes have buffered no fuch abufe. With regard to the turning 
 black with alcalies, it is fo far from being a mark of Arfenic, that the beft 
 and purefl Mercurius dulcis changes to a blackifh grey colour both with fixt 
 and volatile alcalies. 
 
 Mercurius dulcis , called alfo calomelas , manna metallorum , panchymagogum mi- Merccriua 
 nerale , aquila alba , and draco mitigatus , is a combination of corrofive Sublimate dulcis. 
 with freih Mercury ; or more properly, it is a combination of the marine acid 
 with as much Mercury as that acid is capable of corroding or uniting with; 
 whilft the corrofive Sublimate is a combination of Mercury with as much of 
 the acid as it is capable of abforbing. The Mercurius dulcis is fometimes called 
 Mercurius fublimatus dulcis ; but the -title fublimatus is better omitted, left the 
 foregoing corrofive Sublimate fhould chance to be confounded with the mild 
 one: a miftake which once actually happened, and which coft the patient his 
 life : The perfon who made up the prefeription pleaded in excufe, that he 
 knew but of one Mercurius fublimatus , and did not think it fafe to tafte whether 
 it was fweet or not. 
 
 In making Mercurius dulcis , the principal point is, to take crude Quickfilver 
 enough to fully fatiate the acid of the corrofive Sublimate. Some are aecuf- 
 tomed to employ an under proportion of Quickfilver, with a view to render 
 the preparation of a fine white colour and cryftalline appearance : But thefe 
 qualities, far from being of any advantage to it, or any marks of its good- 
 nefs, denote rather that it continues in fome degree corrofive : It is not the 
 
 Q 2 colour 
 
Mercurial Pa> 
 nacea. 
 
 ioo Metallic Bodies. 
 
 Mercury, colour or crydalline form we are to regard; if it is clean, and perfectly in- 
 iipid, it is a good Mercurius dulcis. The Mercury fhould be taken in equal 
 quantity to the Sublimate, or at lead three parts of Mercury to four of Subli- 
 mate; tiie ingredients thoroughly mixed together in a glafs or done mortar; 
 then poured through a long funnel into a glals body, and iublimed : All the 
 
 matter which arifes is to be reduced again into powder, and fublimed a fecond 
 time in a fredi matras. The managements to be obferved in the procefs are, 
 to let the glafs pretty deep in thefand ; not to raife the fire too hadily at fird; 
 and as foon as the fuperfluous Quickfilver has arifen, to remove part of the 
 land all round the fides. The fublirnation may be repeated three or four times 
 or oftner, but this nowife contributes to the perfection of the medicine : If 
 there is Mercury enough, a good Mercurius dulcis may be made by one fubli- 
 mation; and if there is not, no number of lublimations will fupply the de- 
 ficiency. Mercurius dulcis might be made even by one Tingle operation, from 
 the ingredients which corrofive Sublimate is prepared from, by taking the 
 Mercury in a diffidently large quantity. Some, after having by two fublima- 
 tions obtained a duly dulcified Sublimate, have Iublimed it a third time from a 
 little common Salt and Caput Mortuum of Vitriol : This renders it crydalline, 
 but at the fame time makes it corrofive again by fupplying frefh acid. 
 
 The mercurial Panacea is a Mercurius dulcis, fublimed eight or nine times 
 or oftner in frefh glades, then digefted in Balneo with rectified Spirit of Wine 
 for a fortnight, and afterwards dried. There is alio a black mercurial Panacea, 
 or a violet coloured Mercury fublimate, prepared from Mercury, Sal ammoniac 
 and Sulphur by repeated fublimations ; but it is not in ufe. It is pretty ex- 
 traordinary, that two volatile fubftanees, often fublimed together, fhould fix 
 one another: That corrofive Sublimate is thus fixed by Sal ammoniac, fo as 
 no longer to fublime, appears a paradox, but is a faff. 
 
 There are two mercurial Sublimates made with Sulphur, not diftinguifhed 
 however by the name of Sublimates, but of Cinnabars, factitious and antimo- 
 nial. Both Cinnabars confift wholly of Mercury and Sulphur, and differ only 
 in the manner of combining them together. For the factitious Cinnabar, the 
 Mercury and Sulphur are both employed in their pure date : But for the Cin- 
 nabar of Antimony, the Quickfilver is previoufiy united with marine acid into 
 corrofive Sublimate, and the Sulphur is united with Regulus of Antimony into 
 crude Antimony. The ufe of taking the ingredients fo combined does not re- 
 gard the improvement of the Cinnabar, but the obtaining of another prepara- 
 tion at the fame time : The acid of the Sublimate forfakes the Mercury and 
 corrodes the antimonial Regulus, and thefe two, diddling together, form what 
 is called Butter of Antimony: Then follow the Mercury and Sulphur com- 
 
 bined into Cinnabar. The antimonial Cinnabar is commonly of a worfe co- 
 lour than the factitious, inclining to blackifh, from the proportion of Sulphur 
 being fomewhat larger : When its colour turns out the bed, it is not at all 
 fuperior to the other. 
 
 Factitious Cinnabar, called fimply Cinnabar or Vermilion, is no wffiere pre- 
 pared in the way of trade but in Holland : The Dutch have not themfelves one 
 grain of either of the ingredients; but procure them, with fundry others, from 
 us [in Germany] ; and then laugh at our fimplicity in giving up to them fuch 
 
 profitable 
 
 Cinnabar of 
 Antimony. 
 
 ’f-'adtitious 
 
 Cinnabar. 
 
101 
 
 Metallic Bodies. 
 
 profitable manufadlures- To one part of Sulphur, they take from fix to Mercury. 
 
 eight parts of Quickfilver ; and having melted the Sulphur, dir in the Mer- 
 cury, and mix them thoroughly together : This mixture is made in the quan- 
 tity of a hundred weight at a time. For fubliming velfels, they ufe large, 
 oblong, coated glafs, or earthen jars nearly of the fame width from end to end : 
 
 Thefeare hung in a furnace by a throng rim of Iron. When the matter is put 
 in, the mouth of the veflel is covered, the fire increafcd by degrees, and con- 
 tinued for feveral hours till all the Cinnabar has fublimed ; care being taken to 
 introduce at times an Iron rod to keep the middle clear, othervvife the Cinna- 
 bar concreting there and flopping up the paffage, would infallibly burfh the 
 veffels. I remember an accident of this kind in the royal garden at Paris; 
 
 Mr. Boulduc had contrived a method by which he laid Cinnabar might be 
 fublimed more expeditioully than in the common way-, but the blocking up of 
 the neck of the vefifel not being provided againft, the whole flew in pieces at 
 once, with a horrible explofion (ji). 
 
 The Cinnabar lublimes in large cakes, of a dark red colour, and a needled 
 or ftriated texture like Antimony. The Dutch grind it into powder in mills 
 made for that ufe ; which no ftranger is permitted to fee : Though I have been 
 feveral times in Holland, and fpared no pains or expences, I have never been 
 able to obtain any further information about this part of the manufacture, than 
 that Urine or Brandy are added in the grinding. The painters find, that the 
 Vermilion ground by the Dutch dries fooner than any other, and hence fufpeft 
 that fome foreign matter is mixed with it; pure Vermilion drying exceeding 
 flowly : In fome parcels, white or red Lead are faid to have been difcovered, 
 though fuch as I examined gave no marks of either of thefe, only a fmall por- 
 tion of brown earth being left upon refubliming it. However this may be, we 
 ihould always chufe, for medicinal ufe at lead, Cinnabar in the cake, as being 
 lefs iiabie to adulteration than that which is ground into powder. Its total 
 evaporation in the fire may be looked upon as a fure mark of its purity. 
 
 There are fundry mercurial Precipitates, properly fo called, as being pre- Mercurial 
 pared by precipitating Mercury from its dilutions in acids by means of certain Precipitates., 
 additions. Sea-falt, Sal ammoniac, or Spirit of Salt, added to a folution of 
 Mercury in Aqua fortis, throw down a white Precipitate, differing little from 
 corrofive Sublimate ; the Mercury forfaking the nitrous acid in which it was 
 dilfolved, and uniting with the marine into a concrete lefs diffoluble. Spirit 
 of Sal ammoniac, added to the fame folution, throws down a white Precipitate 
 much lefs corrofive. Corrofive Sublimate, diffolved in water, yields alfo with 
 volatile alcalies a white Precipitate mild like the preceeding. Solution of Sub- 
 limate, mixed with a folution of crude Sal ammoniac, depofites upon adding 
 
 fixe 
 
 («) Cinnabar.'] Hoffman gives a curious manner. I have varied the experiment, by 
 method of making Cinnabar without fubfi- employing, inftead of the volatile tincture, 
 mation ; by (baking or digefting a little the more eafily parable folutions of Sulphur- 
 Mercury with volatile tinAure of Sulphur: made with fixt alcalies, and with Quick - 
 
 The Mercury readily imbibes the Sulphur lime ; and with thefe alio I have obtained' 
 from the volatile Spirit, and forms with it a perfedf Cinnabar, of a brighter or darker 
 a deep red powder, not inferior in colour colour according to the proportion of Sul - 
 so the Cinnabar prepared in the common phur. 
 
102 
 
 Metallic Bodies. 
 
 Mercury, fixt alcaiies a like white Precipitate ; but if fixed alcalies are added to a folu- 
 ^ tion of Sublimate alone, the Precipitate is of an orange colour. A folution of 
 Mercury in Aqua fortis yields, like the folution of Sublimate, an orange co- 
 loured Precipitate both with fixed alcaline Saks and with Lime-water : A Pre- 
 cipitate made from it with warm urine is of a reddifh or role colour. 
 
 Red Precipi- Solutions of Mercury infpiflated are called alfo, improperly, Precipitates; 
 sate. Red Precipitate is prepared by evaporating a folution of Mercury made in 
 
 Aquafortis, and gently calcining the remaining dry matter, till it acquires a 
 fparkling yellowifh-red colour : The greatefl quantities of this preparation are 
 made by the manufacturers of Sublimate, who fave the expence of Aquafortis 
 by employing the fpirit which ariles in that operation. If the red Precipitate 
 be reduced into fine powder, and frefh parcels of rectified Spirit of Wine 
 diftilled off from it or burnt upon it, its corrofivenels is confiderably abated; 
 a part of the acid being difiipated in the burning, or arifing with the fpirit in 
 diftillation, fo as to change it into a Spiritus nitri dulcis : The preparation is now 
 called Mercurius \ pracipitatus corollatus , or arcanum corallinum. in England, 
 the red Precipitate is dulcified alfo by grinding it on a levigating flone with a 
 few drops of Oil of Tartar per deliquium, and afterwards burning rectified 
 fpirit upon it : Thus prepared, it is called pulvis principis. In fome places a 
 green Precipitate is made from folution of Mercury in Aqua fortis, by adding 
 a folution of Verdegris : This is named, lacerta viridis, and antivenereum mer- 
 
 Turpeth mi- curiale : The Copper renders it too dangerous for any internal ufe Theyel- 
 
 j-eral. ] ow Precipitate, called turpeth mineral , is prepared by boiling Quickfilver with 
 an equal weight or more of Oil of Vitriol in a retort, and continuing the fire 
 till the matter has become thoroughly dry and the vefTel red hot. Warm 
 water poured on the white mafs which remains, turns it inllantly yellow; after 
 which the matter is to be wafhed with frefh parcels of water, till the liquor 
 comes off perfectly infipid. If Oil of Vitriol be feveral times drawn over from 
 Mercury, the mafs proves confiderably fixed in the fire : It melts without eva- 
 porating, and whilft in fufion looks like blood. 
 
 Calx of Mer- The mercurius pracipitatus per fe is properly a calx of Mercury. It is pre- 
 cary per le. pared by digefting the Mercury for a length of time, feveral weeks or even 
 months in a fiat bottomed glafs, flightly ftopt or covered with paper to keep 
 ©ut duft, but by no means luted or hermetically fealed as fome direCt, a com- 
 munication with the external air being neceffary to the fuccefs of the procefs : 
 No more Quickfilver fhould be put into one glafs than is fufficient to cover its 
 bottom : The veffel fhould be placed in fand, in fome furnace where a con- 
 ftant heat is to be kept up, and the fand raifed round the glafs a very little 
 higher than the furface of the Mercury within : The degree of heat is one of 
 
 the principal points; if too ftrong, the Mercury will be difiipated, and if too 
 weak, it will not undergo the intended change : It fhould be gentle at firft, 
 
 andincreafed with caution. When a quantity of calx or red powder has thus 
 once been obtained, the admixture of this with frefh Mercury remarkably pro- 
 motes its calcination. From this circumflance the philofophers by fire have 
 been led into many different ipeculations, which in general have but little 
 foundation. The change which the Mercury undergoes is not near fo great as 
 they have imagined : On a bare increafe of the heat, it puts off its difguife, 
 
 i and 
 
Metallic Bodies. 103 
 
 and refumes its original running form. Mercury may be changed into powder Mercury, 
 
 by bare agitation in a clofe veffei : This powder differs from that obtained by v ”~“' v * 
 
 fire in being of a grey or black colour. See page 9 1 . 
 
 Sundry mercurial waters, and oils as they are called, are employed by the Mercurial 
 furgeons, almoft every one having a preparation of this kind of his own. waters. , 
 They are all only diluted folutions of Mercury; having for their bafis either 
 folution of corrofive Sublimate, or a folution of Quickfilver in Aqua fortis. 
 
 A dram of Sublimate, diffolved in a pint of Plantane water, makes the aqua 
 divina of Fernelius. 
 
 Amalgamation, or the folution of metals in Mercury, is ranked as one ofAmaigama- 
 the chemical operations: In fome cafes it feems to depend as much upon thehon. 
 Mercury being divided by the metalline powder, as on its power of diffolving 
 the metal as a menftruum. For obtaining an amalgam or a kind of pafte of 
 Quickfilver and metals, the metal fhould previoufly be reduced into fmall 
 parts, either by mechanic operations, as granulation, filing, or by folution 
 in acids and precipitation : The precipitation fhould be made, not with Salts, 
 for the calces thrown down by Salts will not unite with Mercury; but with 
 fome other metal : Thus Silver is to be precipitated by Copper, Copper by 
 Iron, &c. Heat promotes amalgamation : By its a Alliance we may obtain 
 
 amalgams of fome metallic bodies that cannot be amalgamated without it. 
 
 See page 65. 
 
 Much has been talked of folid or coagulated Mercury ; but all the prepara- Coagulated 
 tions oft is kind, if they have any Mercury in them, are no other than hard Meicur y* 
 amalgams. When melted Lead or Tin are juft becoming confident, a flick 
 is thruft into the metal, and the hole filled with Quickfilver : By the time 
 the whole is grown cold, the Mercury is found fold and crumbly, the heat 
 having promoted the union of the metal with it. Maurice Hoffman, in the 
 adts of the Altdorff elaboratory, gives a procefs for reducing the Mercury fo 
 coagulated to a date of malleability, by repeatedly melting and quenching it 
 in Linfeed-oil : A malleable metal is thus really obtained, which may be 
 
 formed, as he promifes, into rings ; but it is not Mercury : All the Mercury is 
 diffipated in the fufions, and nothing is left but the Lead or Tin. Still more 
 ridiculous are thofe, who melting an amalgam of Copper along with Tutty, 
 imagine the Brafs that refults to be a production of the Mercury. 
 
 A diaphoretic fixt Mercury has been a grand objedt of purfuit among the 
 chemifts. I have met with many pretenders to fuch an arcanum, but have 
 never yet found any truth in their pretences ; ignorance of the principles of 
 genuine chemiftry, and of the properties of the bodies which they worked 
 upon, having led them to believe, that when they had loft their Mercury, they 
 had fixed it. One made his fixt Mercury, by diffolving two ounces of Quick- 
 filver in Aquafortis, adding by degrees one ounce ofRegulus of Antimony, 
 and then mixing a quantity of brine of Sea- fait : The matter being now exfic- 
 cated, he proceeded to the fixation, that is the diflipation, of the Mercury, by 
 deflagrating the mixture with Nitre. 
 
 But the moft extraordinary of all the preparations, which the alchemifts Alkahefh 
 have pretended to make from Mercury, is the aikaheft or univerfal menftruum. 
 
 Kunckel has Ihewn the abfurditv of fuppofing them poffeffed of fuch a 
 
 menftruum. 
 
104 Me t ajl l i c Bodies. 
 
 Mercury, menftruiim, by a Ample queftion, (C If it will diffolve every thing, what 
 “ veffel can it be kept in ?” 
 
 Mineral hif- Quickfilver is found in the earth, fometimes in its running form, but much 
 ■t«y- more commonly in that of an ore. The native running Mercury, called Vir- 
 
 gin, has been preferred by fome to that which is extracted from the ore and 
 purified by art 5 but no experiment affords any foundation for fuch a prefe- 
 rence. The ores are of three kinds, (1) fine red ones, called native Cinnabar, 
 differing from the fadlitious Cinnabar only in having fome earthy, ftony, or 
 other heterogeneous matters intermixed, (2) ftony ores, and (3) clayie or 
 loamy earths. The two laft forts are much poorer in Mercury than the firft : 
 They contain more Sulphur than is requifite for forming a red cinnabarine 
 compound, and appear commonly of a blackifh or greyifh-black colour, with- 
 out io much as a fpeck or a vein of red. 
 
 Mines of Quickfilver are extremely rar e(o). The only confiderable ones 
 known are in fome parts of the imperial hereditary dominions, and in Spain; 
 particularly at Friuli and Iftria in Carinthia ; and at Alm'aden de la Sierra Mo- 
 rena in the province of Eftremadura. The ores in the imperial dominions are 
 chiefly of the cinnabarine kind •, theSpanilh, poorer and more earthy : Spain 
 however produces as much Quickfilver as Friuli, or rather more. At Alma- 
 den, in the year 1717, there were twenty-five thoufand quintals or Spanilh 
 hundred weights of Quickfilver, which amount to above three millions of 
 pounds of our weight : From thence are fent yearly to Mexico, fleets laden 
 with Quickfilver, for the amalgamation and extradition of Gold and Silver 
 from the rich minerals of that country : The exportation either of Mercury or 
 Cinnabar to other places, is prohibited. The mines of Friuli have been ob- 
 tferved to afford 695,33 4 pounds of Quickfilver in three years : All the impe- 
 
 rial Quickfilver is brought to Holland, the Dutch having entered into a con- 
 tract with the Emperor for that purpofe. 
 
 It may be proper to obferve, that Mercury is never found in the mines of 
 any other metals; nor any other metals in the mines of Mercury; except that 
 fometimes a mineral containing a little Gold or Silver fball be met with among 
 mercurial ores, and even this is an exceeding great rarity. This obfervation 
 feems to fufficiently refute the opinion of thofe who hold Mercury to be an 
 hypoftatic principle or ingredienc in all metals : For if merals were, and con- 
 tinued to be, produced from Mercury, we certainly fhould, fometimes at 
 leaft, difcover one where the other is. 
 
 Lemery, Pomet and others lay down fome external marks, for diftinguifh- 
 ing thoie places in which there are mines of Quickfilver ; namely, thick va- 
 pours, like clouds, arifing in the months of April and May ; the plants being 
 much larger and greener than in other places ; the trees feldom bearing flowers 
 or fruit, and more flowly putting forth cheir leaves. But thefe marks are far 
 
 from 
 
 {0) Mines of Quickfilver rare.] According 
 to Hoffman’s computation, the annual pro- 
 duce of Gold from mines is fifty times 
 greater than that of Quickfilver. Cramer 
 fufpedb he means only five times ; and that 
 
 Quickfilver occurs in the earth more fre- 
 quently than we are aware of ; this volatile 
 femimetal being diffipated in the common 
 proceffes by which ores are worked or 
 affayeu. 
 
Metallic Bodies. 105 
 
 from being certain : They are not obferved in all places where there is Quick- Mercury-. 
 fiver, and they are obferved where there is none. In the Hartz-forek we fee — v ~ — 1 1 
 
 abundance of thofe cloudy exhalations, though not a grain of Mercury is 
 
 found there. 
 
 The method of extracting Quickfilver from its ores differs according to -the Extra&Ion 
 fubftances naturally joined to it. For the imperial cinnabarine ores, certain from ores ' 
 additions are employed, to abforb their Sulphur, as filings of Iron : Or the 
 ore is dikilled per defcenfum in perforated iron pots. The Spanifh ores require 
 no addition, nor any iron veffels, thefe naturally containing a calcareous earth 
 fufficient to imbibe the Sulphur: The ore being thrown in at one end of a 
 
 furnace, the Mercury is extricated in fume from all its natural admixtures, 
 and after palling through a number of horizontal aiudels, condenfes in a re- 
 fervoir at tire further extremity. In iome places the more impure ftony ores 
 
 are damped, and the lighter matters wafhed off from them ; after which, the 
 
 more ponderous and pure part is diddled either by itfelf or with additions ac- 
 cording to its quality. An account of the Spanifh Quickfilver furnaces may 
 be feen in the French Memoirs for the year 1719. 
 
 The finer coloured cinnabarine ores are never worked for Mercury, but em- Cinnabar, 
 ployed as Cinnabar ; and have by many been injudiciously preferred to the more 
 pure factitious Cinnabar. We feldom meet with any native Cinnabar that has [T natural 
 not a viiible admixture of earthy or ftonv matter, nor with two pieces that per- ‘ 
 feCtly agree. 
 
 Makes of native Cinnabar are found in Hungary, Tranfylvania, Carinthia, 
 
 Bohemia, the Palatinate, France, Spain, fometimes in Sweden, and as is faid 
 in the Eaft-Indies, particularly Japan, but greatefl part of what is fold under 
 the name of Japan Cinnabar, is manufactured in Holland. In the fhops, three 
 principal forts are dikinguifhed, (1.) Cinnabar in makes, fotne of which weigh 
 one, two, fix ounces, and more. (2.) Cinnabar in grains, prepared by break- 
 ing the coarfer makes, and picking out the bits of Cinnabar from the kony 
 matter intermixed, (3.) wafhed Cinnabar, prepared from fuch makes as are 
 kill fouler, by reducing them to powder, and wafhing off their lighter impuri- 
 ties. The firk fort is accounted the bek, and the lak the work. Many have 
 been particularly fond of the Hungarian Cinnabar, fuppofing it to be impreg- 
 nated with Gold, becaufe in Hungary there are mines of Gold : So far has this 
 ridiculous conceit prevailed, that not only the minerals, the Cinnabar, the 
 Antimony, the Copper, the Vitriol, but the very vine-trees of Hungary, have 
 been imagined to participate of that metal. 
 
 Native Cinnabar fhould never be employed for any medicinal ufe without Chemical 
 purification; and the only method of purifying it effectually is fublimation; examination, 
 the ablution, by fome directed, being by no means fufficient. I have never met 
 with any that did not leave on fublimation a grey a fit or fa-nd, 
 
 amounting, 
 
 in 
 
 different parcels, to one ninth, one eighth, one feventh, one fixth, and one 
 fifth of the Cinnabar employed. Sixteen ounces of wafhed Cinnabar left above 
 two ounces of fixt matter : Of the part which fublimed, only about ten ounces 
 were pure compaCt Cinnabar, the rek being fpongy, and not fo clean : By re- 
 petitions of the fublimation, the whole became purer and finer coloured. The 
 
 P refiduum 
 
ig6 M e t a l l i c B o d i e s. 
 
 Cinnabar, refiduum imparted to Aqua regia a yellow colour like that of a folution of 
 Gold ; and Spirit of Sal ammoniac precipitated from this tindture a calx which 
 looked like Aurum fulminans : It did not however fulminate, nor give any 
 other marks of Gold than its colour. What particular fubflance this foluble 
 part of the refiduum was, I did not examine; but it certainly was not Gold, 
 for Aqua fortis diffolved it as well as Aqua regia. 
 
 Some add a little calcareous earth in the fublimation of Cinnabar; to abforb 
 a portion of its Sulphur, and thus improve its colour : It is an over-proportion 
 of Sulphur that makes the colour blackifh, and not, as fome have pretended, 
 too ftrong a fire ; for ftrong fire does no injury to Cinnabar. 
 
 The proportions of Mercury and Sulphur are different in different Cinna- 
 bars : The ordinary forts, purified by fublimation, contain commonly four 
 parts of Mercury to one of Sulphur : The finer have more Mercury. It is 
 obfervable, that though Oil of Vitriol forms with Mercury a lively yellow 
 concrete, Turpeth mineral ; and with the inflammable principle, a yellow 
 Sulphur ; and though this Sulphur forms with Mercury a beautiful red Cin- 
 nabar; yet Oil of Vitriol totally deftroys this red colour, changing the Cin- 
 nabar white as milk. 
 
 II. BISMUTH. 
 
 Bismuth. J^ISMUTH, or Tin- glafs, is a fparkling white femimetal, very ponderous, 
 
 » - i confiderably hard and fonorous, extremely brittle, without any degree of 
 
 Its general malleability, falling in pieces under the hammer, and reducible by triture into 
 properties, f| ne powder. When broke, the furface of the fradture appears compofed of 
 bright plates or flakes, larger than thofe of the other femimetals. In its ex- 
 ternal appearance, it has a great refemblance to Regulus of Antimony and 
 Zinc, differing little otherwife than in the largenefs of the plates, and in its 
 contradcing a yellowifh call on the furface expofed to the air. In its intrinfic 
 properties, it is extremely different ; melting far more eafily, not evaporating 
 fo readily, being differently adted upon by acids, producing different effedts 
 upon other metallic bodies, &c. 
 
 examined by Bifmuth melts in the fire long before it grows red-hot, confiderably fooner 
 Are, even than Lead. Kept in fufion and flirted, it foon calcines; gaining at the 
 
 fame time an increafe in its weight, of near half an ounce upon a pound. The 
 calx melts, upon raifing the fire a little, into a brownifh or yellowifh glafs 
 which promotes the vitrification of earths and the refradtory metallic calces 
 more powerfully, and corrodes and finks through the common crucibles more 
 readily, than glafs of Lead itfelf. If Bifmuth be mixed with Gold or Silver, 
 a heat that is but juft fufficient to melt the mixture, will prefendy vitrify a 
 part of the Bifmuth, which then having no addon on thofe perfedt metals, fe- 
 parates and glazes the crucible all round (/>). 
 
 Calx 
 
 ( p ) Bifmuth.'] This femimetal approaches 
 in fpecifie gravity to Silver, being nearly ten 
 times heavier than an equal bulk of water. 
 It melts a little later than tin, and feems to 
 
 flow the thinneft of all metallic fubftances. 
 When in fufion, it occupies lefs volume 
 than in its folid Hate ; a property peculiar 
 to Iron among the metals, and Bifmuth a- 
 
 mong 
 
Metallic Bodi£s. 107 
 
 Calx ofBifmuth, long reverberated, does not, as fome pretend^ become Bismuth. 
 red like the calces ol Lead. It fcarccly retains even the form of a calx, a part — v ~ — -J 
 oftheBifmuth being revived into its metallic appearance by the flame : None 
 of the deilruftible metallic bodies is fo eafy ol revival as this femimetal. If 
 the vefiel is covered, and all inflammable matters excluded, vitrification is the 
 only change that enfues. 
 
 The nitrous acid diffolves Bifmuth with great effervefcence, and a copious by the nitrous 
 difcharge of yellow corrofive fumes. The folution, if the Bifmuth has not ac Vfi 
 been too haftily added to the acid, proves colourlefs and tranfparent (q ) : Di- 
 luted with a large quantity of water, it becomes milky, and depofites on 
 (landing a fine white Precipitate or Magiftery ; which edulcorated by repeated 
 aftufions of water, is employed as a cofmetic, both in wadies and pomatums, 
 under the name of Spanish or pearl white. 
 
 There are fundry variations in preparing this Magiftery. Some take Aqua Magiftery of 
 regia for the menftruum; and lor the precipitant, a Solution of Sea-falt, alca- Bifmuth, 
 lies, Spirit of Wine, &c. Some mix with the Solution ofBifmuth, a Solution 
 ofBenzoine in Spirit of Wine, and thus obtain a MagiStery compofed of calx 
 of Biimuth and Benzoine. Others add a folution of Chalk to- the metalline 
 folution, and precipitate both together with alcalies. I have made trial with a 
 good number of different precipitants, and found, that with common fixt Alcalr 
 and cauftic Alcali, with watery and vinous alcaline fpirits, the Magiftery was 
 white, and in confiderable quantity ; the liquor after the precipitation with vola- 
 tile Spirits, appearing blue : That Oil of Vitriol threw down a white Precipitate 
 very copiously ; but that with Spirit of Vitriol, Spirit of Salt, and weak Spirit of 
 Nitre, the Precipitate was in very fmall quantity, in colour white like the forego- 
 ing-, and that diftilled Vinegar made no precipitation at all : That common 
 rectified Spirit of Wine and tartarized Spirit, common water and Lime-water, 
 gave white Precipitates : That Solutions of Nitre, vitriolated Tartar, Sal mirabile. 
 
 Alum, Borax, common Salt(r), Sal ammoniac, the combination of calcareous 
 earth with marine acid called fixed Sal ammoniac, and the terra foliaca Tartari, 
 
 all 
 
 mong the femimetals. It emits fumes in 
 the fire fo long as it preferves its metallic 
 form : When calcined or vitrified, it proves 
 perfectly fixed. 
 
 (q) Nitrous acid.] Proof Aqua fortis dif- 
 folves about half its weight ofBifmuth : If 
 the folution is haftily performed, the liquor 
 appears greenifh. A part of the Bifmuth 
 cryftallizes almcft as fall as it diffolves, or 
 at leaft as foon as the heat arifing from the 
 action of the acid ceafes, unlefs the men- 
 ftruum is diluted with about an equal quan- 
 tity of water Both fixt and volatile al- 
 
 calies totally precipitate it. Volatile alca- 
 lies, added in larger quantity than is fuffi- 
 cient for that effedf, take it up again : The 
 liquor generally appears greenifh ; by alter- 
 nate additions of the alcaline Spirit and of 
 the folution, it becomes bluifh or purple. 
 
 Fixed alcalies, calcined with inflammable 
 matter, likewife rediffolve the Bifmuth after 
 they have precipitated it. 
 
 (r) Precipitate by Sea-falt.] It has been 
 commonly fuppofed that Sea-falt or its acid 
 carry down Biimuth from its folution in the 
 nitrous acid, in the fame manner as it does 
 Silver, Lead, and Mercury. A folution of 
 Sea-falt will indeed precipitate all the four, 
 but with this difference, that the precipi- 
 tates of the three latter are foun/j intimately 
 combined with the acid of that Salt; whilft 
 the Precipitate of Biimuth retains nothing 
 of it, and was thrown down, not by the 
 faline, but by the aqueous pait of the liquor. 
 Simple water precipitates it, but Sea-faff 
 undiffolved, or a folution of it added- in 
 fmall quantity, dqes not, 
 
 P 2 
 
io 8 
 
 Metallic Bodies. 
 
 Bismuth, all precipitated the Bifmnth white: That with a folution of Gold in common 
 — ) Aqua regia, the Magiftery proved grey ; with a folution of the fame metal in 
 an Aqua regia made with Spirit of Salt, it was likewife grey, but in much lefs 
 quantityj with folution of Copper in Aqua fortis, white, and in very fmall 
 quantity, the liquor continuing blue; with folution of Vitriol of Copper, 
 white; with folution of Mercury lublimate, white and plentiful ; with folution 
 of Iron in Aquafortis, yeliowifh •, with folution of Lead in Aqua fortis, and of 
 Sugar of Lead, white; with folution of Zinc in Aqua fortis there was little 
 Precipitate; and with folutions of Silver, of Tin, of Regulus of Antimony, 
 and of Mercury, in the lame acid, none at all. On boiling fome powdered 
 Bifmuth in a folution of green Vitriol, the liquor did not grow turbid, as it 
 would have done by itfelf, but rather clearer and clearer : A fixt alcaline Lixi- 
 vium being afterwards added, it turned white and thick, but on Landing for 
 fome time depofited a greenifh matter, which on drying changed to a light 
 brown : A little of the liquor evaporated and fet to fhoot, yielded cryftais, 
 
 which in appearance and tafte refembled Vitriol of Iron. 
 
 Some prepare the Magiftery of Bifmuth, by fubliming the powdered Bif- 
 muth with Sal ammoniac, diffolving the flowers in diddled water, and then 
 precipitating with volatile or fixt Alcali : Others add Nitre in the fublimation, 
 but this addition rather injures than improves the colour of the product : And 
 indeed the Sublimates obtained by either method are lefs fit for making the 
 Magiftery than Bifmuth in fubftance, for the folution of them, whatever care 
 is taken in the operation, will not be limpid, but green. Some, infteadofthe 
 Magiftery, diredt a calx to be made by deflagrating the Bifmuth with Nitre, 
 expedting that the Bilmuth will detonate like Antimony, and that the calx will 
 reiembie that of Antimony prepared in the fame manner : Others direct the 
 flowers which arife during the deflagration, to be caught in aludels for the 
 fame purpofes. But Bifmuth, though it is very readily calcined by Nitre, 
 does not fenfibly deflagrate with it : The flowers and the calx are not perfectly' 
 white, but yeliowifh -, and the quantity of the flowers is fmall, only two ounces 
 having been obtained from fixteen. 
 
 The Magiftery of Bifmuth appears to have fome latent corrofive quality j 
 and when freely ufed as a fucus, not to be entirely innocent: It gradually im- 
 pairs the natural complexion; and leaves, for old age, a coarfe and difagree- 
 ablefkin. The peruke- makers are laid to employ it in their pomatums for 
 giving a whitenefs to grey, reddifn, yellow, or other coloured hair ; and 
 Pomet obferves that a fhower of rain will walh off this adventitious whitenefs. 
 I have been informed alfo, that thofe who bleach hair in England make ule 
 of this Magiftery ; and therefore I determined to examine by experiment its 
 effedts upon hair. Experiment fatisfied me that the report was groundlefs 
 that the .Magiftery of Bifmuth does not whiten hair but darken it; that it 
 changes the whiteft flaxen hair firft to a yeliowifh, then to a yellowifh-brown, 
 afterwards to a dark brown, and at laft to a black. The trial may be made 
 in two ways ; by boiling the hair in water along with the Magiftery ; or by 
 applying the Magiftery mixed with Pomatum, and hanging the hair in the 
 fun : The oftener this is repeated, the darker will the colour be. We may 
 judge from hence, that this Magiftery is lefs fit for the purpofes of acofmetic, 
 
 than. 
 
M e t a l l r c Bod i e s. 109 
 
 than it is generally fuppofed to be. The Magiftery itfelf has been commonly Bismuth. 
 believed to change its colour in the fun, and hence it is cl 1 redded to be dried u— v—w 
 cautioufiy in a fhady place ; but- it did not appear to have iuffered any confi- 
 derable alteration on being ex'pofed to the fun for two months, it is apt, 
 however, in length of time, to turn yellowifh ; and hence a iarge flock fnould 
 nor be prepared at once. 
 
 Spirit of Sea- fair, though long boiled with Bifmuth, diffolves very little ; treated with 
 and Aqua regia not much. The effeCt of the concentrated marine acid j n marine aad. 
 Mercury fublimate I was induced to try, from Mr. Boyle’s account of a pearl- Pearl-colour, 
 like fublimate obtained from Bifmuth and that mercurial preparation. One ec * powder, 
 part of Bifmuth in fine powder and two of corrofive Sublimate, mixed toge- 
 ther and expofed to the fire in a retort, immediately melted into a blackifh 
 brown pitch-like mafs : A portion of Quickfilver diftitled, and was followed 
 
 by a dark brown butter, which on cooling grew hard as a done: In the re- 
 
 tort, a little melted Bifmuth remained. On rectifying the butter a fecond and 
 third time fome more running Mercury feparated, the butter became dearer 
 and browner, and at the fame time harder. On a fourth rectification, I had 
 two kinds of butter, a white and a brown. The white being rectified twice 
 by itfelf, an unCtuous pearl-coloured matter remained each time, and the but- 
 ter became dill whiter. The brown was then mixed with the white, and the 
 rectification again repeated fix times : A like pearl-coloured fjbdance was left: 
 in every didillation, the quantity of butter grew lefs and lefs, and at length 
 there was none to be feen. So that by this troublefome operation I obtained 
 the produCt intended by the author, though it was not properly a Sublimate, 
 having remained in the retort after fublimation. 
 
 Oil of Vitriol diffolves Bifmuth into a role-coloured liquor (s), which on with Oil of 
 Handing turns brownifh •, but Spirit of Vitriol has little effeCt. If a folution Vitriol, 
 of Bifmuth in Aqua fortis be evaporated to one half, fome Quickfilver and Oil 
 of Vitriol added, the evaporation continued to drynefs, and the dry matter 
 fet to fubiime ; there arifes fird a little Quickfilver, and afterwards a perfectly 
 white mealy Sublimate: In the bottom of the retort remains a greenifh matter 
 variegated, if the heat has been drong, with rainbow colours. Diddled Vine- 
 gar diffolves a little by drong coCtion, and acquires from it, not, as fome pre- 
 tend, a fweet tade like that of faturnine dilutions, but a confiderably acerb and 
 dyptic one. 
 
 Bifmuth cemented with Sulphur, readily unites with it, and melts eafier than with Sulphur, 
 by itfelf; but on continuing the fire, they foon feparate again, the Bifmuth 
 falling to the bottom, and a fulphureous fcoria fwimming on the furface. Calx 
 of Bifmuth likewife very eafily abforbs Sulphur, and forms with it a curious 
 needled mais, exaCtly refembling Antimony, contracting a reddifh tinge ex- 
 ternally on expoiure to the air : The quantity of Sulphur imbibed is lefs than 
 half the weight of the calx ; a part of the Sulphur having fublimed when the 
 
 operation 
 
 (r) Oil of Vitriol with Bifmuth.'] The vi- the author, was probably obtained, not 
 trioiic acid in fome degree corrodes this from Bifmuth itfelf, but from Bifmuth ore ; 
 femimetal, but does not perfectly diffolve the ore participating of a metallic fubftance 
 it, however concentrated or abided by heat, of a different kind, which gives a reddifh 
 The rote-coloured folution, mentioned by colour to all acids. 
 
110 
 
 Metallic Bodies. 
 
 Bismuth, operation was performed, in a retort, with that proportion. Silver, added to 
 this antimoniated concrete, melts with it, in a very gentle heat, into a brittle 
 Reg ulus : Gold alfo unites with it, but requires a much (Longer fire •, the com- 
 pound is brittle, in appearance like an ore, with here and there feme ft rise or 
 (Lining particles. Copper melts with it, in a fmall heat, with remarkable faci- 
 lity; and after they have been united, the compound continues to retain this 
 extraordinary fufibility : On the addition of Lead, a new combination hap- 
 pened : the Copper and Sulphur arofe to the furface in fcoria refembling an ore, 
 whilft the Bifmuth and Lead formed a Regulus at the bottom, 
 with different With regard to the effeifts of Bifmuth upon metals (/), ( r.) Equal parts of 
 metals, Bifmuth and Gold, melted together, formed a quite brittle Regulus, which had 
 fcarcely any yellowifh hue, and looked almoft like Bifmuth itfelf ; as focn as 
 they began to melt, a vitreous matter appeared round the crucible. (2.) Equal 
 parts of Bifmuth and Silver formed a white compound, lefs brittle than that 
 with the Gold : It bore the hammer a little, and feemed at fir it as if it was going 
 to extend, but at laft it cracked. The fame fudden vitrification was obferved, as 
 in the foregoing experiment. (3.) With Tin, it melts exceeding eafily : The 
 mixture at fir ft frequently emits fmall flames, and a part calcines: When the 
 quantity of each was half an ounce, the lofs was five grains. If the fire is 
 railed, the compound quickly calcines, like a mixture of Lead and Tin, into 
 a yellowifh white afh. A fmall portion of Bifmuth improves the brightnefs, 
 hardnefs and fonoroufnefs of Tin. (4.) Copper is faid to be changed of a Silver 
 colour by Bifmuth ; and hence the femimetal has been named marcafita ar- 
 gentea ; as Zinc, from its making Copper yellow, is called marcafita aurea. In 
 my experiments, there was no appearance of a Silver colour, except that when 
 the Bifmuth was in very large proportion, its whitenefs prevailed above the 
 rednefs of the Copper. Copper mixed with an equal weight of Bifmuth had 
 its red colour only diluted or rendered paler, and its malleability deftroyed : 
 A part was changed in the fufion, into a dark red fcoria, amounting to a 
 dram upon half an ounce of each of the ingredients. (5.) Equal parts ofBif- 
 muth and Lead yielded a dark grey compound, which bore to be bent a little 
 without breaking: The lofs in fufion was two fcruplc-s upon half an ounce of 
 each of the metals. (6.) Iron and Bifmuth, in the fame proportions, emitted 
 flames in the fire, and in a ftrongheat united together. (7.) The fame quan- 
 tities of Regulus of Antimony and Bifmuth melted perfectly together, and loft 
 only fifteen grains : The mixt looked like Regulus of Antimony by itfelf. 
 (S.) Zinc and Bifmuth did not unite at all, the Zinc flowing diftimft upon the 
 furface, and burning as it does by itfelf. (9.) Mercury forms with Bifmuth 
 
 an 
 
 (l) Bifmuth with metals .] Bifmuth does not 
 mingle in fufion with Regulus of Cobalt or 
 Z inc : The addition of Nickel or Regulus 
 of Antimony, renders it mifcible with the 
 former, but not with the latter. It unites 
 with all the others, and greatly promotes 
 both the tenuity -and facility of their fufion. 
 It whitens Copper and Gold, and improves 
 the whitenefs of fome of the white metals : 
 Mixed in coniiderable quantity, it renders 
 
 them all brittle, and of a flrudlure, like its 
 own, flaky or plated. Though it poflefles 
 feveral properties of Lead, and in certain 
 circ urn fiances remarkably fubtilizes that me- 
 tal, yet in mixture they agree but ill toge- 
 ther : On expofing compofitions of them 
 to a moderate fire, a colludlation enfues, 
 and both metals fall quickly into a calx, 
 like a mixture of Lead and Tin, 
 
Ill 
 
 Metallic Bodies. 
 
 an amalgam, which readily adheres to Iron : If the Iron, coated with the Bismuth. 
 amalgam, be expoied to the fire, the Mercury exhales, and greateft part of C— -v— 
 the Bifmuth remains fixt upon the Iron, which now looks as if it had been 
 filvered. If mixtures of Bifmuth with fome other metals, particularly Lead, 
 be amalgamated, the Lead is found to be fo attenuated, as to pafs with the 
 Quickfilver through leather : On Handing, the Bifmuth is thrown up to the 
 furface in form of a dark coloured powder, the Lead remaining diffolved in 
 the Quickfilver. (to.) Equal parts of Lead, Copper and Bifmuth, yielded 
 aRegulus of a looty black colour on the upper furface : The lofs in fufion 
 
 was one dram upon three half ounces of the mixture. (1 1.) Equal parts of 
 Lead, Tin and Bifmuth, formed a blackifh fparkling compound, refembling 
 the fmall-diced ores of Lead. (12.) It is obfervable, that the fpecific gravity 
 of a mixture of Bifmuth and Copper is exactly the mean gravity of that of the 
 two ingredients unmixed; but that mixtures with Iron are fpecifically lighter 
 than the ingredients feparately; and mixtures with Gold, Silver, Tin, Lead, 
 and Reguius of Antimony, heavier. 
 
 Bifmuth is applied to various ufes in the chemical arts, as (1.) For making Ufes. 
 Pewter with Tin ; this metal being of itfelf too foft for the common purpofes 
 of utenfils, and never being worked without fome additional metallic matters, 
 of which Bifmuth is one of the principal, (a.) For foldering Lead and Tin ; 
 a mixture of Bifmuth with thele metals being eafier of fufion than either of 
 them feparately. The common folder is compofed of two parts of Lead, two 
 of Tin, and one of Bifmuth (it). (3.) As an ingredient in the compound me- 
 
 tal for Printers types. Types indeed are often made, without any Bifmuth, 
 from a mixture of one part of Copper, one of Antimony, and five of Lead ; 
 butHomberg, a celebrated German chemift who ended his days in Paris, has 
 obferved, that the addition of Bifmuth and Tin greatly improves the compofi- 
 tion : He advifes equal parts of thefie to be melted together, and one part of 
 this mafs to be melted with fix of the ordinary mixture. (4.) In foils for mir- 
 rours ; the common mixture for thefe purpofes con fills of one part of Tin, 
 
 ©ne of Lead, two of Bifmuth, and ten of Quickfilver, amalgamated together. 
 
 A 
 
 (u) Fufibiliiy of mixtures of Bifmuth , Tin 
 and Lead.] The degree of heat, in which 
 thefe metals by themfelves, and certain 
 mixtures of them, melt or, when melted, 
 begin to fet or grow folid again, has 
 been examined by thermometers. The 
 following'table exhibits nearly their propor- 
 tional fuiibility, compared to the heat of 
 boiling water and Quickfilver, according to 
 Fahrenheit’s fcale. 
 
 600. Quickfilver boils. 
 
 540. Lead melts . 
 
 460. Bifmuth melts » 
 
 41O. Tin melts. 
 
 390. Tin 8. Bifmuth I. melt > 
 
 330. Tin 2. Bifmuth 1. melt. 
 
 Tin 3. Lead 2. melt > 
 
 28 0. Equal parts of Tin and Bifmuth , melt . 
 
 212. Water boils. 
 
 In thefe kinds of experiments, and indeed 
 in all cafes v/here the heat is continually in™ 
 creafing or decreafing, we cannot expedi. any 
 great degree of precifion ; for as the thermo- 
 meter receives only fucceffively the heat 
 which adts upon it, it cannot exprefs the 
 exadt heat of the body applied at any parti- 
 cular inftant of time. Whilft the inftru- 
 ment expreffes one degree of heat, the fur- 
 rounding matter may have acquired a con- 
 fiderably greater or fmaller; and by the: 
 time that the thermometer has rifen or fallen 
 to that degree, the heat of the matter tnay 
 be again varied. 
 
ii2 Metallic Bodies. 
 
 Bismuth. A particular account of the manner of preparing and foiling reflecting glafs- 
 balls may be feen in Boyle’s treatife of the ufefulnefs of experimental phi- 
 lofophy. (5.) In mixtures for anatomical injections, particularly of the lungs: 
 Some take equal parts of Bifmuth, Lead, and Tin; others add a little Qiiick- 
 filver. (6.) For imitating Silver on wood. The turners grind Bifmuth into 
 a fubtile powder, and temper it with whites of eggs : This applied on wood, 
 looks, when dry, of an afh colour-, but on being burnifhed with a tooth, it 
 afiumes the appearance of dufky Silver. (7.) For imitating Silver upon Iron, 
 as mentioned in the ninth experiment of the preceding paragraph. (8.) For 
 purifying Gold and Silver by cupellation, fcorification, Off. For thefe pur- 
 pofesit is preferable to Lead, as it more effectually promotes the deftruCtion of 
 the imperfeCt metals, and the vitrification of earths andcalce. (x). It has one 
 great advantage above Lead in all operations of this kind where Sulphur makes 
 one of the ingredients namely, its forming with that concrete an extremely 
 fufible mafs, whiilt Lead combined with Sulphur proves extremely refraCtory. 
 
 Ahufes, Bifmuth has been too often employed for the adulteration of Quickfilver, as 
 
 rendering a very confiderable proportion of Lead intimately milcible with it: 
 Becher was acquainted with means of combining no lefs than one dram of 
 Lead and the fame quantity of Bifmuth with three drams of running Mercury. 
 Quickfilver fo adulterated, is not only unfit for medicinal ufe, but for the 
 common mechanic purpofes of gilding and fiivering: The workmen obferve, 
 
 that it leaves upon the Gold or Silver a livid leaden hue. The abufe is difco- 
 vered, and the Mercury purified, by diftillation. Some of the Wine-coopers 
 have mixed Bifmuth with Sulphur, for the fumigation of cafks ; but as no 
 good reafon is ailedged for this ufe of it, and as it may be productive of ill 
 effeCts, it ought furely to be rejected. See Wepfer de compofitione noxia fulphu- 
 ratorum cum Bifmutho ; Camerarius’s fylloge memorabiihim medicine, cent. 8. 
 N° 23. and a paper by Dr. Salomon Reifei in the Ephem. nat. curiof dec. 3. 
 (inn. 5 G? 6. Though Bifmuth, however, when thus corroded by the fulphu- 
 reous acid, and diflblved in Wine, may produce dangerous effeCts ; it does not 
 follow that the Bifmuth in Pewter diflies will communicate any ill quality to 
 Vinegar or the other acids ufed in food ; diftilled Vinegar extracting nothing 
 from Bifmuth without ftrong coCtion. 
 
 Medical ef-' This femimetal has been held by fome in confiderable efteem as a medicine. 
 
 fefts. The Magiftery, the Calx, the Flowers, and fundry other preparations of it, 
 
 have been laid to be diaphoretic ; to be ferviceable in virulent gonorrhseas, 
 gouty complaints, and contractions of the limbs. But experience affords little 
 
 foun- 
 
 (.v) Ufe of Bifmuth in cupellation .] Bifmuth 
 is particularly preferable to Lead for the 
 cupellation of Gold or Silver blended with 
 refraCtory matters ; as it procures a greater 
 tenuity of fufion than Lead is capable of 
 doing. Monf. du Fay obferves, that Gold 
 is fometimes met with very eager, pale, li- 
 vid, and difficult of fufion, from an admix- 
 ture, as he fuppofes, of Emery ; and that it 
 is moll effectually purified by means of Bif- 
 muth. The method, which he communi- 
 
 cated to the French Academy for its purifi- 
 cation, confifts in melting it with an equal 
 quantity of Bifmuth and pouring out the 
 fluid part, adding more Bifmuth to the re- 
 mainder and proceeding in this manner till 
 the whole runs out clean, and then working 
 off the Bifmuth upon a cupel ; after which, 
 the Gold is to be again cupelled with Lead ; 
 and laftly, fome corrofive Sublimate to be 
 inje&ed upon it in fufion. 
 
Metallic Bodies, 113 
 
 foundation for thefe virtues, nor even For fuppofing it to be fafe. Some pre- Bismuth. 
 parations of Bifmuth have feemed to reprefs febrile heat 5 but extreme anxiety, 
 and other ill confequences have enfued. 
 
 Bifmuth is extracted from its own proper ore, which is found moft plentifully Counterfeited 
 in Saxony, near Schneeberg, and of which fame quantities are met with alfo in 
 Bohemia, and in England. Many have affirmed that it is an artificial compo- 
 fition, and accordingly delivered proceiTes for making it ; of which proceffcs 
 I tried thofe, which feemed to approach the neareft to probability. Two 
 ounces of Arfenic, one ounce of Yerdegris, half an ounce of Sal gem, and 
 half an ounce of oil Olive, were well ground together : Three ounces of Eng- 
 lifh Tin, melted with this mixture, yielded a Regulus weighing four ounces 
 and two drams, very brittle, of a grey colour, entirely different from Bifmuth 
 in appearance as well as quality. But from four ounces of Englifh Tin, two 
 ounces of white Arfenic, one ounce of white Tartar, and half an ounce of 
 Nitre, cemented and melted together, I obtained a Regulus, weighing three 
 ounces and three drams, fo much refembling Bifmuth, as to be eafily miftaken 
 for it by one who had not thoroughly examined the appearance of that femi- 
 metal. There are however fome differences in the ftrudlure of the two, very 
 obvious upon comparing them together, but which are rather to be feen than 
 defcribed. In their intrinfic properties, they are extremely different: Thus 
 the counterfeit, diffolved in Aqua fortis, forms a bluifh coagulum, whilft the 
 folution of the natural Bifmuth continues uniform and limpid; the counterfeit, 
 calcined and mixed with Sulphur, exhibits nothing of that Angular needled 
 ftrudture, which the natural aflumes in the fame circumftances. Since there- 
 fore it has been reported, that the Bifmuth met with in the fhops is an artificial 
 production, and fince experiment fliews that it is capable of being imitated in 
 its external form though not in its qualities, we ought to be upon our guard 
 againft fuch an impofltion. 
 
 The ores of .Bifmuth are met with chiefly in the mines of Silver and of Co- Ores, 
 bait. They are commonly of a fparkling appearance, of a yellowilh colour, or 
 intermixed with yellowifh veins; often reddifh; often variegated with different 
 colours, as bluifh, reddifh, and yellowifh ; and fometimes quite black. The 
 yeliowifli forts are called golden or philofophic marcafites, and have been held 
 in great requeft among the alchemifts. By lying long in the open air, they 
 yield beautiful red ftriated efllorefcenCes, called by the miners Flowers of Co- 
 balt or of Bifmuth. 
 
 Bifmuth ores are aflayed for Bifmuth by pulverizing, and melting them, ATay, 
 in a clofe crucible, with thrice their weight of black flux; a little charcoal 
 duff being fpread upon the furface of the mixture. The Regulus obtained by 
 this procefs is aflayed for Silver, by calcining it with Nitre ; which foon fcori- 
 fies the Bifmuth, whilft the Silver, if it contained any, remains unhurt at the 
 bottom. 
 
 In the large way, the ore, beat into fmall pieces, is placed in a low furnace Smelting i-,. 
 or oven, io contrived, that the flame of the wood may play upon the furface of lar S e> 
 the mineral. The Bifmuth melts out, by a heat no greater than that in which 
 pure Bifmuth melts; and runs off into a cavity made for receiving it; from 
 whence it is taken out, and caff, in moulds, into round cakes. Ercker has 
 
 Q. given 
 
Bismuth. 
 
 Experiments 
 on the ore. 
 Blue glafs, 
 
 changeable 
 coloured li- 
 quor. 
 
 Metallic Bodies. 
 
 given a wooden cut of the manner of fmelting Bifmuth ore; and from this is 
 copied the copper-plate in Valentini’s mufaum mufaorum. The matter remain- 
 ing after the eliquation of the Bifmuth, called WijJ'muthgrau'pen, Bifmuth-earth, 
 or Caput Mortuum of Bifmuth, is employed for making a blue glafs, in the 
 fame manner as calcined Cobalt (jy). 
 
 The crude ore, melted with colourlefs glafs, or a fufible compofition of Sand 
 and alcaline Salt, tinges it blue, deeper or paler, according to the proportions : 
 On melting it with an equal weight of Nitre, the mafs proved likewife blue, 
 but deliquiated in the air : With four times its quantity of the Sal ammoniacum 
 fixum , it formed only a brown concrete, which being boiled in water, almoft 
 all the ore feparated, the liquor acquiring a flight yellowifh tinge. A tindlure 
 drawn from the ore with Aqua fortis, mixed with a faturated folution of Sea- 
 falt and infpiffated, yields a reddifh Salt, whofe colouring matter diflolves 
 both in rectified Spirit of Wine and in water ; a white earthy fubftance remain- 
 ing undiffolved. The red watery folution is the curious liquor, which has 
 lately been kept a fecret, under the name of the green fympathetic Ink. It 
 may feem an impropriety to give a red colour the name of green : But this 
 liquor is truly green, and of a fine green, when heated, as well as red whilfl 
 cold •, and in that ftate wherein it is vifible as an Ink, it is always green. If 
 written with on white paper, the characters difappear as foon as they are dry : 
 If the paper is held to the fire, they become green and legible : On cooling, 
 they difappear again ; and this repeatedly for any number of times (z). 
 
 (y) Bifmuth ore — blue glafs. ~\ The ores of 
 Bifmuth frequently accompany Cobalt, and 
 always participate of its colouring matter, 
 as Cobalt almoft always does of Biimuth. 
 Probably, as Cramer obferves, the two ores 
 differ from one another only in this, that 
 one contains more Bifmuth than the other — 
 The reftduum of Bifmuth ore is faid to af- 
 ford a glafs of a finer colour than that of 
 Cobalt ; and hence Bifmuth has been held 
 a mark of the goodnefs of Cobalt, and fup- 
 pofed to contribute to the beauty of the co- 
 lour. This conclufion, however, appears 
 to be too haftily drawn : For molt Cobalts 
 feem to contain more Bifmuth, than Bif- 
 muth ores do after eliquation. If the obfer- 
 vation itfelf is well founded, it tends rather 
 to prove, that Bifmuth is injurious to the co- 
 lour ; more efpecially as this femimetal is 
 itfelf eafily convertible into a yellow glafs, 
 which fhould feem more likely to debale 
 than to improve the blue colour of the Co- 
 balt glafs. The author of Henckelius redi- 
 vivus mentions a Cobalt mine in Joachimf- 
 thal, abounding with Bifmuth, but yielding 
 a glafs of no value. See Cobalt. 
 
 (z) Sympathetic Ink.] This property of the 
 tinging matter of Bifmuth-ore was publilhed 
 at full length by a German lady in 1705. 
 The compilers of the encyclopedic attribute 
 the difcovery to Mr. Hellot ; though that 
 gentleman himfelf acknowledges that he 
 received the firft hint of it from a German 
 chemift no earlier than the year 1736. 
 The experiment fucceeds beft, when the 
 tinCture drawn from the calcined ore with 
 Aqua fortis is mixed with a folution of one 
 fourth its weight of Sea-falt, the mixture 
 evaporated almoft to drynefs, and the refi- 
 duum diffolved in water. Mr. Hellot has 
 given a variety of experiments on this lub- 
 je£t in the French Memoirs for the year 
 1737. He obferves, that with Nitre or 
 Borax inftead of Sea-falt, the characters be- 
 come rofe-coloured when warmed, and if 
 Sea-falt is afterwards palled over them, 
 blue ; that with Alcali fufficient to faturate 
 the acid, they change purple and red from 
 heat. 
 
 III. ZINC, 
 
Metallic Bodies. 115 
 
 HI. ZINC. 
 
 2^ IN' C (Zincunly Contrefiait, 'Tutenag , Spiauter , Spelter) is a white femimetal, Zinc. 
 
 inclining a little to bluifb, efpecially when compared with the whiter me- 
 tallic bodies, Regulus of Antimony, Tin, or Silver. It is confiderably hard Gen . eral P r0 ~ 
 and fonorous, and lefs brittle than any of the other femimetals : Hammered P eUies ° 
 gently and leifurely, it extends a little, but by a few quick blows, or a fmart 
 one, it cracks or breaks. In fpecific gravity, it cornes the neareft to Tin ; 
 which laft is fomewhat the heavieft of the two {a). 
 
 It begins to melt in a moderate red heat(£) •, and when in fufion, burns and Examine<3 b 7 
 Fulgurates, with a deep yellowifh green flame, a confiderable noife, and an fire * 
 arfenical fmell : If the fluid metal is ftirred, the deflagration continues ftrong, 
 till nearly the whole quantity is deprived of its metallic form and fublimedinto 
 flowers, which concrete about the upper part of the veflel into fine, foft, white 
 filaments, like down or cobwebs (c). It is obfervable, that in a broad Iron 
 ladle, Zinc in filings will not melt near fo foon as the fame quantity in one 
 piece; whereas, when bodies are reduced into fmall parts, they commonly melt 
 the foonefl: : The difference in this cafe probably arifes from the filings ex- 
 pofing a larger furface to the external air, and the communication of the heat 
 being intercepted by the vacuities betwixt them : The filings flrewed upon 
 
 burning coals, melt and deflagrate much fooner than larger pieces. The face, 
 
 viewed 
 
 harder, more brittle, lefs fufible, and lefs 
 calcinable ; that after the two firft fufions, 
 its colour was grey, after the third brown, 
 and after the fourth black ; that the fifth 
 rendered it of a date blue ; and the fixth of 
 a clear violet. 
 
 (r) Flowers .] The flowers once fublimed 
 from this femimetal are no longer capable 
 of being elevated by the ftrongeft fire. In 
 a heat far greater than that in which they 
 arofe at firft, they fuffer no alteration : In a 
 very vehement one, they melt according to 
 Henckel (del. Nat. Cur. tom. iv.) into a 
 femi-opake green glafs : Vitrified with Bo- 
 rax, they give a grey or browniftr glafs — ■ — 
 
 From the Angular texture of the flowers 
 they have been called philofophic Wool, 
 
 Cotton, Silk, and Talc: From the ftrong 
 green flame with which they fublime, they 
 are fuppofed by fome to be the fubftance 
 veiled by the aichemifts under the tides of ^ 
 
 the golden fleece guarded by fiery bulls, 
 and the dry v/ater extracted from the fun- 
 beams ; and the femimetal itfelf to be the 
 Sun, the Lucifer, the green Lion, and the 
 Dragon that vomits fire. 
 
 0.2 
 
 (a) Zinc.) This femimetal makes a crack- 
 ling noife in bending, like that of Tin, but 
 louder : Broke, it appears internally of a 
 fiffile plated texture, partly dull coloured, 
 partly bright and fparkling. Expofed to 
 the air, it contracts, in length of time, a 
 kind of yellowifh ruft. It is fomewhat duc- 
 tile when cold, but when heated proves 
 entirely brittle. Its fpecific gravity is to 
 that of water as 7 V- to 1. 
 
 (b) In the fire.) It begins to melt as 
 foon as it grows red-hot ; but does not 
 flow thin, or burn, or fublime, till the fire 
 is raifed to a white heat. Kept juft in fu- 
 fion, it calcines, flowly, not only on the 
 upper furface, but likewife round the fides, 
 and at the bottom of the crucible : If feve- 
 ral pieces are juft melted together, the mafs, 
 when grown cold, may be broke into the 
 fame number, their union being prevented 
 by a yellowifh calx, with which each piece 
 is all over covered. Malouin relates, in 
 the French Memoirs for the year 2742, 
 that a quantity of Zinc being melted fix 
 times, and the fufion continued fifteen hours 
 each time ; it proved on every repetition 
 
 o 
 
i c : 6 
 
 Zinc. 
 
 "V""* - 
 
 Flowers. 
 
 Reduction 
 she flowers, 
 
 Metallic Bodies. 
 
 viewed by the flame of Zinc, looks like that of a dead corps : The flame of 
 Phofphorus, and of Spirit of Wine impregnated with Sea-falt, exhibit the 
 
 fame phcenomenon. 
 
 The veftels commonly made life of for fubliming flowers of Zinc, are two 
 crucibles ; one placed in the fire, for containing the Zinc ; the other inverted 
 upon it, by way of cover : This laft is every now and then taken off, and the 
 Zinc ftirred. Some perform the fublimation in a wide necked glafs retort; 
 others in an ear then body, 1 have made a great number of experiments 
 
 for determining the moft fuccefsful method, and the moft commodious appara- 
 tus : I have tried open and covered crucibles, earthen and glafs retorts, gentle 
 and fcrong fires, large and fmall quantities, with and without ftirring, in fhort 
 all the different ways I could think of. In this examination it appeared, 
 (i.) That Zinc does not begin to fublime when it begins to melt, but may be 
 kept a good while in fufion without deflagration or diflipation. (2.) That the 
 fublimation commences with the burning and noife. (3.) That by a ftrong fire 
 in an open crucible, a confiderable quantity, commonly one fourth its weight, 
 is totally diffrpated ; but that by a gentler heat the lofs is much lefs. (4.) That 
 glafs retorts are entirely unfit for this purpofe, as they are apt to crack from the 
 heat neceflfary for keeping Zinc in fufion, and as the fublimation, if they happen 
 to Hand the fire, doe? not well fucceed in them. (5.) That earthen retorts an- 
 fwer better ; but that thefe alfo are liable to an inconvenience ; a grofs Subli- 
 mate arifes after the finer flowers, and in breaking the neck of the retort, we 
 cannot avoid mingling the two together. (6.) That when two crucibles are 
 uled, the more fubtile flowers, whofe quantity is but fmall, arife into the up- 
 per moft ; the more ponderous remaining in the lower, adhering to its Aides, 
 and filling the veifel as it were with a fubftance like burnt Alum, which proves 
 more and more compact and grofs from the top to the bottom. (7.) That the 
 flowers already fublimed, mull, if we expedf any more Sublimate, be from 
 time to time taken away •, Zinc requiring room, and the accefs of frefli air, for 
 its fublimation. In ftirring the Zinc, or removing the flowers, care muft be 
 had, that none of them fall down upon the melted Zinc ; for if they do, they 
 will never rife again, but remain a fixt calx, covering the metal and prevent- 
 ing its fublimation. The belt method, upon the whole, appears to be this : 
 A large crucible being placed in a wind-furnace on a piece of brick, and made 
 moderately red-hot, but not too ftrongly heated, the Zinc is to be thrown in, 
 in pieces : The crucible may be covered till the Zinc begins to burn, but after 
 this period ic fhould be kept open : When any confiderable quantity of flowers 
 is obferved in the crucible, they are to be cautioufly taken out with an iron 
 ladle, and this continued till nothing more will arife, or till the whole quan- 
 tity of the Zinc is burnt. By this method the produce of flowers is greateft; 
 greater even than the weight of the metal employed: From half an ounce I 
 obtained half an ounce and fifteen grains. 
 
 F I have made fundry experiments for reducing the flowers of Zinc into Zinc 
 again. I urged them in a crucible, with tallow; but they fcarce changed their 
 colour; I treated them with Pitch and with Wax, but obtained only a blackiflr 
 grey powder. Two drams of the flowers were put into a coated earthen re- 
 tort, with an ounce of powdered Charcoal, and a receiver containing fome 
 
 water 
 
 o 
 
Metallic Bodies, i i 7 
 
 water clofely luted to the retort: The fire was railed by degrees, and kept up Zinc. 
 ilrongfor feme hours, that there might be no deficiency in point of heat : But u— . 
 upon unluting the veflels, I found in the neck of the retort only a yellow and 
 grey Sublimate, with a few fparkling metallic particles : The coal at the bot- 
 tom weighed fix drams and one fcruple : A Ikin appeared upon the water in 
 the receiver, and a little powdery matter fubfided. The experiment was re- 
 peated, with the addition of fome Beef-fuet to the Charcoal, and without any 
 water in the receiver ; but this time I obtained only an empyreumatic Oil from 
 the Suet, Sundry trials were made likewife with alcaline Salts and Borax ; 
 without fuccefs. At lad, having melted one dram of the flowers with fix 
 drams of Borax, in a quick fire, injedfed pellets of powdered charcoal made 
 up wdth fat, and quenched the crucible in water, I found on breaking the vef- 
 fel, frnall granules of revived Zinc, with a blackifh grey femivitreous fcoria, 
 
 Jt appears from the whole, that the reduction of thefe flowers, though diffi- 
 cult, is not impracticable : Probably more fuccefsful methods might be difeo- 
 vered, if the enquiry was of any particular utility or importance ( d) . 
 
 I have fometimes granulated Zinc, by pouring it, when melted, into a 
 wooden box, well rubbed all over on the infide with Chalk, and ftrongly 
 fhaking it. But in all the experiments with Menflrua, I ufed filings. It 
 feems as if part of the file was abraded by the Zinc, fome of the particles being 
 attracted by the Magnet; and this may poffibly happen alfo in the filing of 
 other metals, though not hitherto obferved. Granulated Zinc is not touched 
 by the Magnet. 
 
 Oil of Vitriol did not diflolve Zinc, though an ounce of the acid was taken treated with 
 to half a dram of the metal : After feveral days digeftion, the filings were only 0l1 °f Vitriol, 
 corroded into a white calx. Spirit of Vitriol made a complete folution : Its 
 aCtion was accompanied with a confiderable heat, and an inflammable vapour, 
 like that which ariles during the diflolution of Iron. At firft, a grey and 
 blackifh, fpongy, flaky matter feparated and arole to the furface, and foon 
 after fell to the bottom, but on Handing for fome days was taken up and dil- 
 ap- 
 
 (, d ) Reduction of the flowers .] From the 
 difficulty of recovering Zinc from its flowers 
 and calces, the chemifts have been led to 
 fuppofe either that they are irreducible, or 
 that the phlogiftic principle of Zinc is of a 
 different kind from that of other metallic 
 fubftar.ces. A more careful examination 
 has difeovered, that fuch inflammable mat- 
 ters, as reduce other calces, reduce equally 
 thofe of Zinc ; and that the difficulty lies, 
 not in reviving, but in preferving this vola- 
 tile femimetal after its revival. All calces, 
 thofe of Iron excepted, require a ftronger 
 fire for their reduction than that in which 
 the metal itfelf melts ; and a full melting 
 heat is the greateft that Zinc can fuftain : 
 Hence, in the inftant of its revival, it burns 
 and calcines again if the air is admitted, 
 and in clofe veffels efcapes, at leaft in part. 
 
 through their pores. On mixing flowers 
 of Zinc with powdered Charcoal, and urg- 
 ing them with a itrong fire in a crucible, a 
 deflagration and frefii fublimation enfue ; 
 fufficient marks, that the Zinc has been re- 
 duced into its metallic form ; for fo long as 
 it remains in the ftate of calx, neither of 
 thefe effedts can happen. If the veffel is fo 
 contrived, as to exclude the air, and at the 
 fame time allow the reviving femimetal to 
 run oft from the vehemence of the heat into 
 a receiver kept cool, the Zinc will there 
 concrete and he preferved in its perfedtme- 
 talic ftate. It is ftill more effectually de- 
 tained by the addition of certain metallic 
 bodies, as Copper, and Iron ; with which 
 the Zinc, when thus applied, unites more 
 readily and perfectly, than it can eafily be 
 made to do by other means. 
 
1 18 
 
 Zinc. 
 
 with nitrous 
 acid. 
 
 with marine 
 acid, 
 
 Metallic Bodies^ 
 
 appeared in the liquor, nothing being left but a little yellowifh dull: fcarcely 
 worth mentioning. The liquor is as limpid and colourlefs as the Spirit of 
 Vitriol itfelf. 
 
 Spirit of Nitre or Aquafortis has a ftronger appetite for Zinc than any other 
 acid, and than this acid has for any other metal. It a6ls with great violence, 
 and heat, and a copious difcharge of reddilh-yellowilh- brown vapours ; and 
 prefently diffolves almoit the whole of the Zinc into a colourlefs tranfparent 
 liquor. 
 
 Spirit of Salt likewife attacks Zinc very readily, but does not a<5t near fo 
 violently, or diffolve it fo expeditioufly, as Spirit of Nitre. A little fine 
 blackifh fubftance appears during the diffolution, nearly like that which fepa- 
 rates with Spirit of Vitriol : But this alfo is at length diffolved, only an incon- 
 fiderable portion of dufty matter remaining. The. liquor is almoft colourlefs, 
 or very (lightly yellowifh. 
 
 Aqua regia aits on Zinc pretty violently, and diffolves it fpeedily, leaving, 
 as in the foregoing experiments, a very little powdery matter. This folution is 
 of a citron yellow colour; in which refpecft it differs from all the others. 
 When an Aqua regia made with Sal ammoniac was employed, fome fmall 
 cryftals of Zinc fhot at the bottom. 
 
 Difiilled Vinegar feems at firftto have little adtion on this femimetal : But 
 on digefting an ounce of the acid with half a dram of the filings, half a fcruple 
 was at length taken up. The folution looked milky, and had a fweetifh tafte 
 relembling that of faturnine folutions : On filtration, it became clearer, and on 
 (landing (fill more fo ; a little powdery matter having been left upon the filter, 
 
 and a little more gradually depofited to the bottom of the liquor Two 
 
 drams of filings of Zinc being boiled in water with an ounce and a half of 
 powdered Tartar ; the liquor, paffed through a filter, was found to have loft 
 its acidity, and acquired a metallic tafte; and the Zinc to have loft a fcruple 
 of its weight. 
 
 with alcalies. Alcalies, both fixed and volatile, were digefted with filings of Zinc for a 
 fortnight, but neither of them feemed to have made any folution. The metal 
 appeared however to be in fome meafure corroded; the fuperficial part having 
 loft its metallic afpeft, and changed to a black colour. In the filings which 
 had been digefted with the volatile fpirit, fome fine white particles were inter- 
 mixed among the black, as if they had been taken up and depofited again by 
 the liquor. 
 
 The flowers of Zinc did not diflblve in Oil of Vitriol, any more than the 
 
 with Aqua 
 regia, 
 
 with vege- 
 table acids. 
 
 Flowers ; with 
 acids. 
 
 femimetal itfelf; but, like it, they diffolved in Spirit of Vitriol, and in the 
 other acids. To try whether they retained any of the inflammable principle, 
 of which Zinc itfelf lb plentifully partakes, I evaporated a folution of them in 
 the nitrous acid to drynefs, and made the dry matter red-hot. It did not burn 
 or deflagrate ; which any inflammable fubftance, treated in the fame manner 
 with the nitrous acid, would have done. Homberg however pretends to have 
 obtained an adual Oil from them: He diffolved fome of the flowers indiftilled 
 Vinegar, by digefting them in frefh parcels of the acid ; and diftilled the folu- 
 tions in a glafs retort : At ftrft, a quantity of phlegm arofe, then the fuper- 
 fiuous acid, and at Iaft an empyreumatic Oil. This Oil, though diftinguiftied 
 
 by 
 
Metallic Bodies. 119 
 
 by the titles of Oleum forum Zinci, Oleum miner ale , and Oleum met all-hunt) is ob- Zinc. 
 
 vioufly no other than a fetid tartareous Oil proceeding from the Vinegar. He < 
 
 endeavoured to evade this objection, by pretending to make the fame kind of 
 Oil by Spirit of Vitriol, without Vinegar; but the experiment has never fuc- 
 ceeded ( e ). 
 
 That Zinc precipitates Iron, Copper, and other metallic bodies from the Precipitate- 
 nitrous acid, and confequently has a greater affinity with that acid than the ons ’ 
 other metals have, was obferved by Stahl : That it precipitates Copper from 
 
 the vitriolic acid, is alfo known : And that it precipitates Iron likewife from the 
 vitriolic acid, is believed, though this particular ftill wants a further exa- 
 mination. I diffolved pure Vitriol of Iron in diddled water, and added to the 
 filtered folution large pieces, fmaller pieces, and filings of Zinc, in the pro- 
 portion of a dram to an ounce of the Vitriol ; digefted the mixtures with a con- 
 fiderable heat; and at laft kept them lor a time actually boiling. Some Preci- 
 pitate there was, but apparently no more, and no other, than what the Vitriol 
 itfelf would have depofited on the fame treatment : The filtered liquor dill 
 
 yielded greenifh cryftals : The Zinc looked blackifh-grey on the furface, but 
 retained its original weight, and diffolved in Aqua, fords into a colourlefs li* 
 quor, a mark that it retained none of the Iron. From the opinion of Zinc 
 having a greater affinity with the vitriolic acid than Iron has, Glauber, Stahl, 
 and others have affirmed that the acid may be diftilied from Vitriol, by the 
 addition of Zinc, with lefs heat, and in a fliorter time, than without that ad- 
 dition : How far this affertion agrees with experiment will be confidered un- 
 der the article Vitriol. Some recommend Zinc to be employed alfo in the 
 diftillation of the other mineral acids; but if a pure acid is wanted, this addi- 
 tion is by no means advifable; part of the Zinc being apt to arife, when the 
 heat is increafed to any confiderable degree. It has been faid, that Spirit of 
 Vitriol, and Spirit of Salt precipitate Zinc from its folution in Spirit of Nitre : 
 
 On trial, Spirit of Salt occafioned no precipitation, and Spirit of Vitriol threw 
 down only a little greyifh matter, like that which feparates during the diflblu- 
 tion of Zinc when the vitriolic acid is applied to it at firft. 
 
 Equal parts of filings of Zinc and powdered Sal ammoniac, being mixed Treated with 
 together, and urged with a gradual fire in a retort; at firft arole, in a very Sal ammo- 
 gentle heat, an exceffively penetrating volatile fpirit, fo ftrong as to ftrike a niac * 
 man down who fhould inadvertently receive its vapour freely into the nofe : 
 
 This came over in fubtile vapours, and was followed by a volatile Spirit of 
 Salt in thick white fumes : In an open fire, white flowers fucceeded, and at 
 
 length 
 
 (e) 0:1 from Zinc with Vinegar.'] Mr. Hel- 
 3ot obtained an oil feemingly different from 
 the foregoing; by digefting the afh-co- 
 loured matter which remained after the dif- 
 tillation, with the acidulous phlegm which 
 came over, for eight or ten days ; diftilling 
 the tinCture to drynefs; and repeating the 
 extraction with the diftilied liquor, till the 
 quantity of dry extraCf thus obtained was 
 confiderable. This refin-like matter, dif- 
 alled in a retort with a ftronger fire, yielded 
 
 a yellowifh liquor and a white Sublimate : 
 The liquor difcovered no mark of oil, but 
 on being paffed upon the Sublimate, imme- 
 diately diiiolved it, and then exhibited on 
 the furface feveral drops of a reddifh oil. 
 Some of this oil was taken up on the point 
 of a pencil, and applied on gold and fiK 
 ver-leaf : In twenty-four hours, the parts 
 touched appeared, in both, equally dif- 
 folved. 
 
120 
 
 Zinc. 
 
 U— > 
 
 Amalgama- 
 
 tion, 
 
 with Lead, 
 
 compound 
 metals. Pew 
 ter, Bronze, 
 CSV. 
 
 Metallic Bodies.' 
 
 length a reddifh and a black Butter. In the bottom of the retort was found a 
 portion of the Zinc in its metallic form, with a little ponderous and fixt buty- 
 raceous matter, which liquefied in the air : The lump was far more brittle than 
 Zinc ordinarily is, of a reddifh colour on the outfide, and blackifh within : 
 The bottom of the retort was variegated with yellow and red colours, and 
 looked extremely beautiful. The remaining Zinc was mixed afreffi with equal 
 its weight of Sal ammoniac, and the procefs repeated : A volatile alcaline 
 
 fpiritand marine acid were obtained as at firft:, and in the retort was found only 
 a little black matter. When the Zinc was taken at firft in twice the quantity 
 of the Sal ammoniac, the part that preferved its metallic form proved lefs 
 brittle than in the foregoing experiment ; the retort appeared variegated in the 
 fame manner. On endeavouring to rectify the butter, the retort parted in two 
 by the time that one half had diftilled. 
 
 Melted Zinc, poured into heated Quickfilver, readily amalgamates: One 
 dram of Zinc, and two or three drams of Mercury form a hard brittle amal- 
 gam ; one part of Zinc and five of Mercury, a foft one. Equal parts of Zinc 
 and Lead, melted together, and poured into fix times their weight of Quick- 
 filver, yielded a foft butyraceous amalgam, which ground with water, gra- 
 dually threw out the Zinc, whilft the Lead remained united with the Mercury. 
 
 It is affirmed in books, that a little Zinc thrown upon melted Lead, will 
 inftantly take fire, and calcine the Lead. On an ounce of Lead in fufion, I 
 inje&ed a dram of Zinc, but no flame or calcination enfued : The Lead, when 
 cold, looked brighter, whiter, and harder. Two drams being injected on an 
 ounce, part of the Zinc fwam long upon the furface, and feemed averfe to 
 unite with the Lead, though they were frequently ftirred together. Equal 
 parts united, by a lufficient heat, into a compound harder and more brittle 
 than the Lead, and which in bending made a crackling noife. As no defla- 
 gration happened in thefe experiments, I inverted the procedure, melting the 
 Zinc in a crucible by itfelf, and injecting upon it different proportions of 
 Lead : The Zinc now fulgurated inftantly on the contact of the Lead, and 
 
 fublimed into flowers, leaving the Lead in its metallic form at the bottom of the 
 crucible: The flowers were extremely fine, and had often a reddifh caft. 
 
 The principal ufe of Zinc is in metallic compofitions (/), the bafis of which 
 is always either Copper or Tin : It renders Copper of a yellow or Gold colour. 
 Tin brighter and whiter, and both of them harder and more fonorous. The 
 
 finer 
 
 (f) Zinc with other metals .] Zinc does not 
 mingle in fufion with Bifmuth or the femi- 
 metallic fubftance called Nickel : How 
 carefully foever it be ftirred and mixed with 
 either of thefe, the Zinc, when grown cold, 
 is found diftind: upon the furface, fo as to 
 be readily feparated by a blow. It unites 
 difficultly with Iron, Jefs fo with Copper, 
 eafdy with the other metals. 
 
 Combined with Iron or Copper, it renders 
 them more eafdy fufible, harder, and like 
 itfelf brittle whilft hot, though confiderably 
 4 
 
 malleable when leifurely cooled. It bright- 
 ens the colour of Iron almoft into a ftlver 
 hue ; and changes that of Copper to a 
 
 yellow or gold colour -It greatly debafes 
 
 the colour of Gold, and deftroys its mallea- 
 bility ; rendering near an hundred times its 
 weight of that moft duCtile metal brittle and 
 intractable. A mixture of equal parts of 
 each is very hard, white, and bears a fine 
 polifh, and hence is propofed by Mr. Hellot 
 for making Specula : It is not fubjeCl to ruft 
 or tarnifh in the air, like the metals com- 
 monly 
 
I 2 I 
 
 Metallic Bodies. 
 
 finer kinds of Pewter have an admixture of Zinc, the proportion of which to Zinc. 
 the Tin is kept a fecret by the workmen : It is often very final], and fome- — v— — 
 times does not amount to above a pound in five or fix hundred pounds of 
 Tin. Princes-metal is a mixture of Zinc and Copper-, and all the compound 
 metals made in imitation of Gold are at bottom the fame, differing only in the 
 proportions and fome other circumftances w'hich contribute to the malleability or 
 colour. Mr. Geoffroy, in the French Memoirs for the year 1725, has given 
 an account of feveral experiments on this fubjedt : The competitions which he 
 found to anfwer belt, are the three following. (1.) Two ounces of Copper, 
 one ounce of Zinc, and four ounces of Refin: Thefe yielded a pale, but a 
 
 malleable metal. (2.) Equal parts of Zinc and Brafs : This mixture was much 
 higher coloured than the foregoing, but a good deal more brittle. (3.) One 
 ounce of Copper, ten drams of Zinc, and one dram of Iron. All thefe 
 cornpofitions require a confiderably ftrong fire for their fufion. It is ob- 
 fervable that Mercury-fublimate feems to deftroy that quality in Zinc by 
 which it makes Copper brittle-, and hence is made ufe of by thofe who bronze 
 Copper, or render it fuperficially yellow, in order to its being drawn into wire 
 for laces. Such is the dudlility of Copper and Zinc fo prepared, that the wire 
 
 and 
 
 monly made ufe of for that purpofe, of 
 
 which Copper is the bafts It improves 
 
 the colour and luilre of Lead and Tin, 
 renders them firmer, and confequently bet- 
 ter fitted for fundry mechanic ufes. Tin, 
 with a fmall proportion of Zinc, forms a 
 fine kind of Pewter : Lead will bear an equal 
 weight, without lofing too much of its 
 malleability — Malouin obferves, that Arfe- 
 nic, which whitens all other metals, ren- 
 ders Zinc black and friable; that when the 
 mixture is performed in dole veffels, an 
 agreeable aromatic odour is perceived on 
 opening them ; that Zinc, amalgamated with 
 Mercury and afterwards recovered, proves 
 whiter, harder, and more brittle than be- 
 fore, and no longer crackles on being bent. 
 
 Mixtures of Zinc with other metals ex- 
 po fed to a ftrong fire, boil and deflagrate 
 more violently than Zinc by itfelf. Some 
 globules of the mixture are ufually thrown 
 off during the ebullition, and fome part of 
 the metal calcined and volatilized by the 
 burning Zinc : Hence this femimetal has 
 been called metallic Nitre. Gold itfelf 
 
 does not entirely refift its addon It vqry 
 
 difficultly volatilizes Copper ; and hence 
 the Sublimates obtained in the furnaces in 
 which Brafs is made, or mixtures of Cop- 
 per and Zinc melted, are rarely found to 
 participate of that metal. On melting 
 Copper and Zinc feparately, and then pour- 
 
 ing them together, a violent detonation im- 
 mediately enfued, and above half the mix- 
 ture was thrown about in globules. 
 
 Zinc with Sulphur.'] Zinc does not unite 
 in the leaf! with Sulphur or with crude An- 
 timony, which fcorify all other metallic 
 fubftances except Gold and Platina ; nor 
 with cornpofitions of Sulphur and fixed al- 
 caline Salts, which difiolve Geld itfelf. 
 Hence Zinc may be purified from the Lead, 
 of which it commonly has fome admixture, 
 by injeding Sulphur upon it in fufion; the 
 Lead being abforbed by the Sulphur, and 
 forming with it a concrete which floats un- 
 melted on the furface and may be eafily 
 feummed off, 
 
 Zinc with Nitre.] Zinc deflagrates vio- 
 lently with Nitre. Its flowers do not fen- 
 fibly deflagrate, yet alcalize double their 
 weight of the Salt, more readily than Zinc 
 itfelf. The alcaline mafs appears exter- 
 nally greenifh, internally of a purple colour : 
 It communicates a fine purple to water, 
 and a red to Vinegar. The acetous tinc- 
 ture, infpiflated, leaves a tenacious fub- 
 fiance, which foon runs in the air into a 
 dark red cauftic liquor, the aleahefl of fome 
 of the pretended adepts. Mr. Hellot ob- 
 ferves that this liquamen, far from radi- 
 cally diffolving Gold as it has been laid to 
 do, precipitates and revives it from its folu- 
 tion in Aqua regis. 
 
122 
 
 Metallic Bodies. 
 
 Zinc, and laces, notwithftanding their great tenuity, remain every where coated with 
 the Bronze, and difcover nothing of the Copper underneath. A certain perfon 
 in Saxony has lately difcovered a jubilance, of which a fmall portion, inje&ed 
 into a large quantity of melted Copper, changes the Copper into a yellow or 
 Princes-metal : This is perhaps forne concentrated preparation of Zinc. The 
 original difcovery of Princes-metal is attributed by lome to prince Rupert, and 
 from him alfo its name is fuppofed to have proceeded : Others obferve, that it 
 was in ufe long before the time of Rupert, for calling llatues, Gfo and that the 
 name Princes-metal is no other than a corruption of Bronze metal. 
 
 Spelter fol- Zinc and Spelter are commonly underftood, both by chemical writers and 
 der. by workmen, as fynonymous names for the white femitnetal we have been 
 
 treating of. In England, a yellow metallic body, ufed as a folder, is diftin- 
 guilhed by the name of Spelter, and fuppofed by many to be a particular kind 
 of Zinc naturally yellow. I have been told by fome, that it is found in Corn- 
 wall; by others, that it comes from America : But have never met with one 
 who could give any fatisfadory account of its origin; and fufped it to be no 
 other than an artificial compofition of Zinc and Copper [which it is now known 
 to be]. Thus much is certain, that pure Zinc is never yellow. 
 
 Zinc not arti- Zinc ^ as been by many to be an artificial compound, and many 
 fecial. ridiculous conjedures have been advanced about the manner of its produdion. 
 
 Some have confounded it with Bifmuth, with Tin, with different metallic 
 mixtures; and Dr. Schmieder, in the Eph. nat. cur. cent. 3 G? 4. is whimfical 
 enough to believe, that the filaments which we often find hanging in the air 
 in fummer, from the induflry of the fpider, are true flowers of Zinc. Hom- 
 berg prepared a metalline cobweb-like matter, which it was more natural to 
 miftake for flowers of Zinc, by expofing Tin andiron to Tfchirnhaus’s burning- 
 glafs. I repeated the experiment with the fame glafs, and obferved that as 
 toon as fome Tin was added to the melted Iron, fine flender filaments immedi- 
 ately arofe, and flew all about, flicking to our clothes, and to the machine. 
 They differed however, even in their obvious appearances from the flowers 
 which Zinc affords, being not only longer, but in fome degree tough and flexible. 
 Method of The greateft quantities of Zinc come from the Eaft Indies,, in large oblong 
 obtaining at p ieces . an d from Goflar, commonly in round cakes or loaves. Of the origin 
 Goflar * 0 f t he Eaft-India Zinc, we have no certain account : The Gofiarian is ex- 
 
 tracted from the Lead and Silver-ores of Rammelfberg by.a particular contri- 
 vance in the flrudure of the furnace. The Zinc, naturally contained in the 
 ore, feparates during the fufion from the other metallic matters, being elevated 
 by the heat in form of fume, which paffes into a refervoir made for that pur- 
 pole in the front wall, over the gutter by which the Lead runs off. The refer- 
 voir for the Zinc is inclofed, on the in fide, by a large flat Hone, only fome 
 chinks being left for the fumes to enter; and on the outfide, by another ilone, 
 which is clofely luted, and frequently fprinkled during the procefs with cold 
 water, to cool and condenfe the fumes. Each ffnelting lafts twenty hours, be- 
 ginning at ten in the forenoon, and ending at fix next morning. When the 
 fufion of the ore is completed, the workman dextrouily ftrikes the outer ftone 
 of the refervoir with an Iron rod, fo as to loofen fome of the luting at the bot- 
 tom ; upon which the Zinc, collected during the procefs, runs out like Quick- 
 
 filver t 
 
Metallic Bodies. 123 
 
 filver : He continues to tap till nothing more will run, then melts the Zinc Zinc. 
 again in an iron pot, and calls it into hemifpherical mafies. I have feveral u— v — — 1 ’ 
 times been at this work, and kept at it two days and a night together without 
 leaving the furnace. 
 
 Though a part of the Zinc is thus obtained in its metallic lorm, a part is 
 alfo diflipatcd, and a very confiderable one adheres to the fides of the furnace 
 in the form of a calx. This is feraped off when the furnace is cold, and em- 
 ployed for the making of Brafs, £s?c. under the name of Ofenbruch, or Cadmia 
 fornacum. There are fundry other Lead-ores which yield the fame kind of 
 Sublimate •, but no attempts have been made to extract aftual Zinc from them, 
 nor is it generally known that this Sublimate proceeds from Zinc. The pro- 
 duce of Zinc is extremely variable, and depends in great meafure, not only on 
 the due contrivance of the cavity for receiving it, but on the care of the 
 workman in cooling it with water. At Goflar, when the due precautions 
 happen to be neglected, there is not fo much Zinc detained as to be worth 
 collecting. 
 
 To change Copper to a yellow colour is one of the molt diftinguilhing cha- Calamine. 
 rafters of Zinc. The lapis calaminaris , cadmia fojjilis , Calamine or Calamy, is 
 well known to poflefs this property, being the ingredient commonly employed ^“ nc ° re 0 
 for turning Copper into Brafs : It makes a finer Brafs than the Cadmia fornacum^ 
 the latter participating of the Lead, which the ore it is obtained from abounds 
 with. Calamine appears therefore to belong to the fame family with Zinc ; to 
 be in reality an ore of that femimetal, though not hitherto worked for it. 
 
 Calamine is confiderably ponderous, the more fo the better ; moderately Natural hif- 
 hard and brittle, or of a confiftence betwixt that of ftone and earth; fome-t° r y- 
 times whitifh or grey, fometimes yellowifh or of a deep yellow; fometimes 
 red ; fometimes brown or blackifh. It is plentiful in feveral places of Europe, 
 as Hungary, Tranfylvania, Poland, Spain, Sweden, Bohemia, Saxony, Gof- 
 lar, France, and in England, particularly in Somerfetfhire, and the northern 
 parts of Wales. It feldom lies very deep, being chiefly found in clayie 
 grounds near the furface: In fome places, it is intermixed with Lead-ores. It 
 is generally walhed from fuch impurities as may adhere to it externally, and 
 calcined in kilns, like thofe in which lime or bricks are burnt, before it is 
 brought into the fliops or to the Brafs-maker. I have obferved, in fome Brafs- 
 works, that when the Calamine had not been calcined fufficiently, the work- 
 men have been obliged to calcine it over again themfelves. Merret informs 
 us, in his notes on Neri, that it mull be burnt only to a certain degree; that 
 when too little calcined, it does not unite with the Copper ; and that when over 
 calcined, it makes the metal brittle. 
 
 The Brafs-makers reduce the calcined mineral into fine powder, in ftamp-£; ra f s , 
 ing-mills turned by water. To an hundred pounds of Copper in fmall pieces, 
 they take forty pounds or more of the powder mixed with a certain quantity of 
 powdered Charcoal ; and divide the mixture into feveral crucibles, fix or eight 
 of which are let down into one furnace funk in the ground. Theprocefs is 
 no other than a cementation, which is continued for different lengths of time 
 according to the quality of the Calamine, fometimes for a day and nighr, 
 
 R 2 * fometimes 
 
i 24 Metallic Bodies. 
 
 Calamine- fometimes two, three, and even five days and nights. The Copper being at 
 Jength changed into Brafs, and brought into fufion, the crucibles are taken 
 out, one after another, and the metal call into a plate betwixt two large flat 
 ilones prepared for this ufe. 
 
 Often one third of the Calamine is taken up by the Copper ; though fome 
 forts of Calamine are fo poor as not to give out above one tenth of their 
 weight (g). The Zinc thus introduced into the Copper may be feparated by 
 amalgamation with Mercury, which unites with the Copper, and leaves the 
 Zinc untouched ; by fufion with common Salt, which will lcorify the Zinc ; 
 or by fire alone, which will burn and diflipate it. If brafs-leaf be held in the 
 flame of a candle, the Zinc will inftantly burn out in a flafh like lightning, 
 and the leaf will become Copper. It is obfervable that Copper impregnated 
 with Calamine, proves much more malleable, and of a yellower colour, than 
 mixtures of the lame metal with equivalent proportions of Zinc in fubflance; 
 probably from the common forts of Zinc participating of Lead : And that 
 though both Zinc and Calamine change Copper to a golden colour, they 
 greatly debafe the colour of Gold itfelf, rendering it pale or white. 
 
 Examined by I examined feveral forts of Calamine by acid menftrua, and found that they 
 adds. a }i nearly agreed. From all the forts, the marine acid extradited molt, and 
 
 acquired a deep yellow colour •, a mark, not of their containing Gold as fome 
 have fondly fuppofed, but Iron : Calcined with Oil or other inflammable mat- 
 ters, they yield adtual Iron to the Magnet, and fome hold fo much as to afford 
 a ferrugineous Vitriol : The Tinctures made in Aqua fortis are likewife yel- 
 low, though not fo deep as thofe in Spirit of Salt Out of fixty grains of 
 
 a pale reddifli Calamine, half an ounce of Oil of Vitriol diffolved feven 
 grains, the fame quantity of Spirit of Vitriol five grains, of Spirit of Nitre 
 eight grains, and Spirit of Salt fourteen grains. Out of fixty grains of yellow 
 Calamine, half an ounce of Oil of Vitriol diffolved eight grains, of Spirit of 
 Vitriol feven grains. Spirit of Nitre twelve grains, and Spirit of Salt feventeen 
 grains. As the vitriolic acid difiolves fo little of Calamine, I had little hopes 
 offucceeding in an experiment related by a certain writer, of changing green 
 Vitriol into white by precipitation with this fofiil : I proceeded exactly accord- 
 ing to his direftions, but obtained only a green Vitriol again. Many things 
 are believed ro be fads becaufe men of learning have written them, and yet 
 when brought to trial, are found to befalfe. 
 
 The Solution in Spirit of Nitre, evaporated to drynefs, yielded a reddifh- 
 brown mafs, which ondigeflion with rectified Spirit of Wine, in a clofe vefifel, 
 exploded and burftthe glafs. A iaturated folutionin the marine acid, concen- 
 trated by abftradting or evaporating part of the liquor, exhibits in the cold an 
 appearance of fine cryftais, which on applying warmth dififolve and difappear. 
 
 A little 
 
 D Quantity of Calamine taken up by Copper. ] treating it with inflammable additions in 
 One third the weight of the Calamine is the clofe veflels, in the form of adtual Zinc. 
 Jargeft yield at the brafs-works, or which From the common Calamine of the fhops I 
 we have any account. This mineral how- have gained thirty-three parts on fixty-four. 
 ever contains often a confiderably greater The foreign Calamines appear, from fome 
 proportion of metallic matter, capable of experiments related by Mr. Marggraf in the 
 being imbibed by Copper, or feparated, by Berlin Memoirs, to be Jefs rich than ours. 
 
Metallic Bodies. 125 
 
 A little of this concentrated folutioa tinges a large quantity of water of a Calamine. 
 bright yellow colour, and at the fame time depofites by degrees a fine, fpongy, — v— - 1 1 
 
 brownifh Precipitate. Glue, diffolved in this folution, and afterwards infpiffated, 
 forms an extremely flippery tenacious mafs, which does not become dry-, and 
 might be of ufe for entangling flies, caterpillars, and other infedts, if it was 
 not too expenfive. Sulphur boiled in the folution, feems to acquire fome de- 
 gree of tranfparency. Thefe experiments are mentioned by Juncker, and it 
 was from thence I was induced to repeat them. I further diftilled the folution 
 with well wafhed fand and found in the neck of the retort a little Sublimate, 
 variegated with red, green, yellow and other colours: The fand appeared 
 
 fpongy and reddifh. The Sublimate liquefied in the air : Digefted for feveral 
 months with highly rectified Spirit of Wine, it gave no appearance of the Oil 
 which Juncker mentions. 
 
 I diftilled four ounces of the reddifh and the yellow Calamine in a retort in Examined by 
 an open fire. From the reddifh arofe a dram and a half of phlegm, which diflillation. 
 changed Syrup of Violets green ; and fome grains of an ammoniacal Salt, which 
 yielded an urinous Tmell with fixed Alcali, effervefeed with Oil of Vitriol and 
 emitted a fulphureous finell, made no change in the colour of Syrup of Vio- 
 lets, burnt in the fire with a bluifh flame and fulphureous fume : The Caput 
 Mortuum was of a brownifh-red colour, weighed three ounces and feven drams, 
 and yielded no faline matter on elixation with water. From four ounces of 
 the yellow Calamine, there arofe three fcruples and a half of phlegm, which 
 changed Syrup of Violets green, but no Sublimate : The refiduum weighed 
 three ounces fix drams and a half, looked brighter coloured than the Calamine 
 at firft, and gave nothing faline on elixation. On diftilling the Calamine with 
 Pot-afh, no remarkable difference was obferved in regard to the quantity of 
 Salt or urinous phlegm. A mixture of four ounces of Calamine and eight 
 ounces of Nitre being injected by little and little at a time into a tubulated re- 
 tort made red-hot, about a dram of Spirit of Nitre came over, and in the 
 neck of the retort was found a various coloured Sublimate : The refiduum 
 was compadt, of a dark red colour, and weighed ten ounces and fix drams. 
 
 Calamine mixed with Sal ammoniac, yielded a yellowifh Sublimate, like that 
 obtained by the fame means from haematites and other ferrugineous minerals-, 
 but of a paler colour, as containing lei's Iron. It does not in the JeafV unite 
 with Quickfilver. 
 
 There is another fubftance common in the fhops, which may be referred toj' u T t v. 
 this head, as it changes, or ought to change, Copper yellow. This is called y 
 Tutty, c Tntia , and by Lemery f Tuthia , in conformity perhaps to the Arabic 
 origin which he aferibes to it, though Avicenna, Serapio, Pliny, and 
 many other ancient writers, (fome of whom undoubtedly underflood Arabic) 
 call it T'ulia. Pomet was the firft who gave any particular account of this fub- Enquiry into 
 fiance: Pie fays it is brought into France from Germany and fome other places its produ&i- 
 where Brafs or Bronze is made. Lemery adds Sweden, and fays it comes from on - 
 Germany, Sweden and other places, &c. Savary, after copying thefe au- 
 thors, makes another addition, that it is one of thofe commodities which come 
 
 from the Levant ; a 
 
 circumftance which feems 
 
 5 
 
 repugnant to the 
 
 former 
 
 pare 
 
126 Metallic Bodies. 
 
 Tut tv. part of the account. Avicenna and Serapio fay it is found in the Indies; 
 — v — J and Garcias denies its being met with in any part of the Indies. This 
 gentleman was informed that it is made from the allies of a tree growing in 
 Perfia, thence imported to Alexandria, and from thence into Europe. Bon- 
 tius fays likewifeit is prepared in Perfia, but denies that it is from the arhes of 
 a tree. Juncker, profeffor of chemiltry at Hall, relates that it is made in 
 Collar and at Schneeberg. And this is all I have found in books about the 
 origin of Tutty. 
 
 With regard to Collar, I am well acquainted with all the works there, and 
 fully latisfied that no Tutty is made at any of them. If made at Schneeberg, 
 it lurely could not have efcaped the enquiries of the induilrious Henckel, who 
 lived many years in that neighbourhood, and fat in the council of mines ; and 
 yet we find him, in his Pyritologia, as much at a lofs about its origin as I am, 
 and obliged to take up with Pomet’s falfe account. I have written to Sweden, 
 but there it is unknown. I have been at all the confiderable founderies of 
 Brafs, Bronze, Bell- metal, &c. in Germany and Holland, that at Woolwich 
 and a noted one in Southwark in England, thofe of France and Italy, 
 without being able to learn anything of Tutty, or to find any perfon who 
 knew what it was, Bontius’s account, that it is a native earth found in Perfia 
 and ufed as a depilatory, cannot be uriderflood of our Tutty, which has no 
 fuch property. 
 
 Of the manner in which Tutty is prepared, and what it really con fills of, 
 we know as little as of the places from whence it comes. Thofe who make it 
 a Sublimate arifing in the founderies, fay it concretes upon Iron or earthen 
 cylinders placed in the furnace for that purpofe, and that it is no other than 
 a fpecies of Cadmia fornacmn : Valentini relates, that the cylinders are of wood, 
 a material which would prefently be deflroyed in the fituation affigned to 
 them. 
 
 A careful examination of Tutty itfelf difcovers more of its origin than we can 
 learn by any other means. Its bafis is apparently an argillaceous earth ; among 
 which we may difcover an admixtureof Calamine or Cadmia fornacum , fometimes 
 of Zinc in coarfe powder, fometimes of Lead-ore, and fundry other fubftances : 
 On the furface are often found afhes or bits of coal, which fhew it to have 
 been baked in the fire. Some years ago, Tutty was extremely fcarce and dear 
 at Berlin : All at once the fhops were flocked, and the price fell. The Tutty 
 now introduced had neither the colour nor compadnefs of the ordinary forts ; 
 nor was it fo fixed in the fire ; one half of it being difiipated. We may there- 
 fore prefume, that Tutty is an artificial compofition, and that this Tutty had 
 been made, for a prefent advantage, by fome perfon not thoroughly acquainted 
 with the art. 
 
 Defcription. The better forts of Tutty are in femicylindrical concave pieces, like the 
 bark of a tree ; ponderous, and fomewhat fonorous ; moderately compad, and 
 generally not eafy to break •, of an afh or moufe-grey colour, often with yel- 
 low or green variegations ; pretty fmooth on the infide, full of cavities or pro- 
 tuberances on the outfide. The entire, compad, grey pieces, are preferred ; 
 the broken, powdery, crumbly, yellow or reddifh, rejeded. Boeder relates 
 that Tutty has a fftarp tafle, but no fuch tafte is perceptible in ours. 
 
 In 
 
Metallic Bodies, 127 
 
 In the following experiments was employed the belt fort of Tutty procurable T 0 t t y„ 
 from the fhops, reduced into powder, in the quantity of fixty grains with each t- — - -J 
 liquor. (1.) Oil of Vitriol diffolved fifteen grains, acquired ared colour, and ^ he! ™ ca! ^ 
 extricated fumes refembling thole of Spirit of Sea-falt. (2.) Spirit of Vitriol^"’"' ' " " 
 took up twenty-four grains, and here alfo marine vapours were perceived. 
 
 (3.) Spirit of Nitre diffolved more than any of the other acids, namely twenty- 
 eight grains out of the fixty : The colour of the folution was a pale yellow. 
 
 (4.) Spirit of Salt diffolved twenty-fix grains, and acquired a yellow tin&ure. 
 
 (5.) Aqua regis diffolved twenty-five grains, and became likewife (lightly 
 tinCtured. (6.) Diftilled Vinegar took up but two grains. (7.) Oil of Tartar 
 per deliquium had no effect. (8.) Solution of cauftic Alcali diffolved ten 
 grains. (9.) Different volatile fpirits, prepared with fixt alcalies and with 
 Quicklime, neither fufferedor occafioned any fenfible alteration ; though fome 
 report that thefe fpirits extract from Tutty a blue tindture. Tutty extricates in 
 fome meafure the volatile Alcali of Sal ammoniac, abforbing and detaining the 
 acid of the Salt: Neverthelefs when Tutty is previoufiy diffolved in acids, vo- 
 latile alcalies precipitate it. Stahl is not a lictle furprized at thefe feemingly 
 oppofite affinities : But Tutty is by no means the only inftanceof them. Pure 
 calcareous earths exhibit the fame phenomena : Expofed to the fire in mixture 
 with Sal ammoniac, they difengage the Alcali, and unite with the acid-, and 
 when diffolved in the acid* the addition of the volatile Alcali will precipitate 
 the fame earth by which it had been itfelf expelled before. 
 
 A piece of compadt grey Tutty, heated fifty times red-hot, and quenched 
 as often in diftilled water, gave no impregnation to the liquor, and did not 
 become crumbly or fuffer any other fenfible change than contracting fome red 
 and other coloured fpecks. A yellowifh and more brittle piece crumbled at 
 the twentieth extinction, and changed its colour more than the preceding, but 
 gave out nothing to the water, Tutty treated with inflammable fluxes, gave 
 no metallic Regulus with Borax, it was reduced into a vitreous fcoria. 
 
 Mixed with Charcoal powder, and cemented and fufed with four times its 
 weight of Copper, it tinged the metal yellowifh. It were needlefs to proceed 
 further in experiments upon a fubftance of fuch precarious qualities ; a fub- 
 ftance of which we feldom meet with two fpecimens entirely alike.. 
 
 Some other productions of Zinc are mentioned by medicinal and metallurgic Pompho- 
 writers under various names, Pompholyx , Diphryges , Nihil , Nihil album , Spodium lyx, &c. 
 grxcorum, Cadmia botrites , zoniies , onychites , oftracites , placites , capnites , &c. u— 
 Thefe are truly what Tutty is pretended to be, impure fublimates or flowers 
 of Zinc, arifing in the furnaces where Zinc, or Calamine, or compound me- 
 tals made with them, are worked., A Sublimate of this kind is expeCted in 
 the (hops under the name of Pompholyx ox Nihil-, but we feldom meet with the 
 genuine Pompholyx there ; maffes compofed chiefly of Chalk with probably 
 a little white Lead, prepared in Saxony, commonly fupplying its place. This 
 counterfeit fort is of a pure white colour ; the genuine is greyifh. The very 
 beft fort is not equal, for medicinal or other ufes, to the flowers obtained 
 from Zinc itfelf. 
 
 Calamine.* 
 
isB Metallic Bodies, 
 
 Zinc. Calamine, Tutty, Pompholyx and the flowers of Zinc, are applied exter- 
 Vt v ‘ — nail y, in unguents and other forms, as deficcatives and epulotics, againft rnn- 
 t r ' ; ‘ ;cal lal ning ulcers, excoriations of the fl<in, and defluxions on the eyes. By fome, 
 they have been exhibited alfo internally : It is faid that the flowers, given 
 
 from fix to twelve grains, prove iometimes fudorific, and fometimes purgative 
 or emetic : That a Magiftery precipitated by fpirit of urine from a folutiotl of 
 Calamine in Spirit of Salt, duiy edulcorated and dried, is a moderately ftrong 
 emetic and cathartic: That a folution of Calamine in Spirit of Nitre, evapo- 
 rated to drynefsand flightly calcined, adts, in doles of ten grains or upwards, 
 as a fudorific. This preparation has been given by feveral perfons in Eng- 
 land, and entitled Sudonftcum calaminaris , and Cadmia diaphoretica. But the 
 internal ufe of pure Zinc is fcarcely advifable ; and that of its crude ore, whofe 
 contents are variable and uncertain, is furely lefs fo. I knew an oculift, who 
 employed this diaphoretic in Collyria with great fuccefs : He digefted the 
 
 powder in Spirit of Wine, in the proportion of an ounce to half a pint for a 
 ftronger preparation, and of two drams to half a pint for a weaker : A little 
 
 of the filtered liquor was dropt into the eye three or four times a day. 
 
 IV. ANTIMONY. 
 
 Antimony. 
 
 Natural hif- 
 wr y. 
 
 Medical hif- 
 tory. 
 
 ^NTIMONY, {Antimonium, Jiibium) is a blackifli mineral fubftance, ftain- 
 * ing the hands, full of long, fhining, needle-like ftrias, hard, brittle, and 
 confiderably heavy. It is found indifferent parts of Europe, as Bohemia, 
 Saxony, Tranfylvania, Hungary and France, commonly in mines by itfelf, 
 intermixed with earthy or ftony matters : Sometimes it is blended with the 
 richer ores of Silver, and renders the extraction of that metal difficult ; Anti- 
 mony volatilizing a part of the Silver, or in the language of the miners, rob- 
 bing the ore. Antimony is feparated from its natural impurities by fufion in 
 an earthen pot, whofe bottom is perforated with a number of holes ; the fluid 
 Antimony paffing through, whilfl the unfufible matters remain behind, The 
 melting vefifel is let into another pot funk in the ground, and which ferves as 
 a receiver: This laft is of a conical figure, and fuch accordingly is the fhape 
 of the loaves of Antimony met with in the fhops. The juncture of the two 
 veffels is clofely luted •, the uppermofi: one covered, and a fire made round it; 
 and feveral fets of this apparatus worked at once. In fome places, inftead of a 
 pot with a perforated bottom, one is taken which has no bottom, and a perfo- 
 rated iron-plate placed betwixt it and the receiver : But the other method is to 
 be preferred, as Antimony in lufion is apt to diflolve a part of the Iron. 
 
 Antimony has been by many efteemed a poifon. In 1 566, its ufe was pro- 
 hibited in France by an edidt of parliament; and in 1609, one Befnier was 
 expelled from the faculty for having given it. The edidt was repealed in 
 1650 ; Antimony having a few years before been received into the number of 
 purgatives, In 1668, a new edidt came forth, prohibiting its being ufed by 
 any one but the doctors of the faculty. Others again have been extravagantly 
 fond of it, and afcribed to it extraordinary virtues, as Alexander von Suchten, 
 Glauber, and Faber: Baft I Valentine ranks it among the wonders of the world, 
 and placed it in a triumphal car. Thus much is certain, that Antimony in its 
 
 crude 
 
Metallic Bodies. 129 
 
 crude ftate is not a poifon, but a medicine of great efficacy ; an excellent re- Antimony. 
 
 folvent and purifier of the juices, if given from four grains to half a dram, v /- — ' 
 
 along with abforbents : That it is capable of being rendered, by various 
 operations and additions, either truly poifonous, or more medicinal than in its 
 crude ftate : That its moft virulent preparations may, by flight managements, 
 be made falutary ; and its moft falutary ones, virulent. 
 
 Antimony is not a pure femimetal, but a fulphurated femimetal. Thrown Compofed of 
 into the fire, it burns with a blue flame and fulphureous vapours : On digeft- Regulus and 
 
 ing powdered Antimony in Aqua regia, the metallic partis dififolved, and the Sulphur. 
 Sulphur left. The Sulphur of Antimony, purified from the metallic part, is 
 perfectly the fame with the common Brimftone of the ffiops, poflfeffing the 
 fame properties, and anfwering the fame ufes : If the femimetal, freed from 
 the Sulphur naturally mixed with it, be afterwards melted with common Brim- 
 ftone, it refumes the appearance and qualities of crude Antimony. Many have 
 imagined, that this mineral, befides common Sulphur, contains a golden or 
 folar Sulphur •, becaufe Antimony purifies, and heightens the colour of. Gold, 
 and becaufe it diftblves, as Gold does, in Aqua regia. But with regard to the 
 folubility in Aqua regia, it is not the fulphureous but the metallic matter of the 
 Antimony that diflolves : If nothing befides Gold and Antimony was adted 
 upon by that menftruum, there might be fome plaufibility in the argument ; 
 but furely when fo many fubftances difiolve in it, as Iron, Copper, Lead, 
 
 Tin, Quickfilver, Zinc, various earths, CtV. folubility in Aqua regis can be 
 no proof of a folar impregnation. In the purification of Gold, the Sulphur of 
 Antimony has no other effedt than common Brimftone would equally produce: 
 
 "When Gold, containing an admixture of other metals, is melted with Anti- 
 mony; the Sulphur, having little affinity with its own femimetal, forfakes 
 it, and unites with the Silver, Copper, or other metallic bodies mixed with 
 the Gold, but has noadlion on the Gold itfelf : Thus only the impurities of the 
 Gold are combined with the Sulphur of the Antimony, into a fcoria which 
 flows on the furface ; whilft the Gold and the femimetal of the Antimony form 
 one compound at the bottom : If this compound be expofed to a ftrong fire, 
 and a free draught or blaft of air, it evaporates in fumes, and leaves the Gold 
 pure behind it. This procefs ffiews the refiftance of Gold to Sulphur, and to 
 the volatilizing power of the antimonial femimetal, but furely gives no foun- 
 dation for imagining a folar Sulphur to exift in Antimony As Gold is the 
 
 only metal [Platina excepted] that totally refills Antimony or its Sulphur, this 
 mineral has been called by the chemills Balneum folius foils , balneum regis , lupus, 
 ul turns judex , &c. 
 
 The feparation of metallic bodies from Sulphur, by fufion, is no other than Precipitation 
 a fpecies of precipitation, and accordingly is called by fome dry precipita- of metallic 
 tion ; as it depends upon the addition of fome third fubftance, whether metal- Re g uIi * n fa- 
 lie or not, to which the Sulphur has a greater affinity than to that metal which i ' 10n * 
 it is already combined with : In confequence of this affinity, the Sulphur in 
 fufion lets go its metal, to unite with the fubftance fuperadded, and forms 
 with this a light fcoria, from which the other fubfides by its own gravity. 
 
 This is the foundation of all the dry partings of metals : Metallic bodies 
 feparated by this dry precipitation are commonly called Reguli, elpecially when 
 
 S brittle. 
 
130 
 
 Metallic Bodies. 
 
 Regulus and 
 Sulphur. 
 
 Methods of 
 
 Antimony, brittle. The metallic part of Antimony, in particular, is diltinguifhed by no 
 ' other name than that of Regulus of Antimony. 
 
 Proportion of The proportion of Regulus and Sulphur in crude Antimony, it is difficult, 
 and fcarce poffible to exabtly determine; as there is always fome lofs in puri- 
 fying either the Sulphur from the Regulus, or the Regulus from the Sulphur. 
 There is reafon to believe, that the Regulus amounts to one half the quantity 
 of the compound, and rather more than lefs. 
 
 The Regulus of Antimony by precipitation is obtained, by melting the An- 
 feparatmgthe simony with fixt alcaline Salts, Iron, Copper, Tin, &V. the Sulphur having a 
 C 2 U a '‘ greater affinity with thefe than with the Regulus, and forfaking the latter to 
 unite with the former. The Regulus prepared with alcalies is c ailed fimple : 
 That with metallic bodies is diltinguifhed by the name of the particular metal, 
 martial^ venereal^ jovial, &c. All thefe methods are attended with fome in- 
 conveniencies. Alcaline Salts effectually abforb the Sulphur ; but they form 
 with it a hepar fulphuriS) which in fufion diffolves all the metals: Hence in- 
 
 proportion as the Regulus is freed from its Sulphur by the Alcali, a part of it 
 is taken up again by the compound which the Sulphur forms with the Alcali : 
 One third, one half, and olten three-fourths of the Regulus are thus redif- 
 folved ; and often, we find very little Regulus left. Metallic additions are 
 free from this inconvenience, and confequently occafion the yield of Regulus- 
 to be much larger: But the Regulus thus obtained is never entirely free from 
 fome portion of the metal fuperadded. Some have endeavoured to promote the 
 reparation of the Regulus by inflammable additions, as powdered Charcoal, 
 Pitch, Refin, but thefe do not at all mend the matter : Antimony treated 
 with inflammable fubftances alone, yields no Regulus ; and if alcaline Salts 
 alfo are taken, the inconveniences will ftill be the fame as when thofe Salts are 
 ufed by themfelves. Many have fubftituted to alcaline Salts, crude Tartar or 
 a mixture of Tartar and Nitre, and thought that then they employed no alca- 
 lies; not aware, that thofe are the very Salts from which alcalies are produced 
 for chemical ufes by the action of fire ; and that they do not here effect the 
 intended reparation, till the heat has reduced them to that date. There are 
 however fome differences obferved in the quantity of Regulus according to the 
 different additions. 
 
 Kunckel has given a method of preparing Regulus of Antimony by calcina- 
 tion. He calcines the Antimony tiil it ceafes to emit any fulphureous fmeli,. 
 with care to prevent its running into lumps; then mixes the calx with oil or 
 fat and a little powdered charcoal, puts the mixture into a crucible to melt, 
 and as foon as the Regulus begins to ffiew itielf, injects by degrees fome pow- 
 dered Nitre, in the proportion of an ounce to a pound of Antimony : The 
 * matter in thin fufion, being poured out, a pure Regulus is obtained, in much 
 greater quantity than by the foregoing methods. There is another, but more 
 expenfive, way of procuring a large yield of pure Regulus; namely, by ex- 
 tracting the Regulus from the Antimony by acid menftrua, as Aqua regis or 
 Spirit of Salt ; precipitating it from this folution ; and afterwards reviving the 
 Precipitate, by melting it with inflammable additions. 
 of Pure Regulus of Antimony, by whatever means obtained, is a bright femi- 
 metal, refemblingTin or dulky Silver; without anything of the bluiffi caff 
 
 of 
 
 Chemical 
 properties 
 she Regulus. 
 
Metallic Bodies. 
 
 131 
 
 of Zinc, or the yellowifh one of Bifmuth. It is one of the lighteft of the Antimony. 
 metallic bodies, [about feven times fpecifically heavier than water] moderately 
 hard, entirely brittle, and of a fparkling plated texture. In a fire not very 
 ftrong, it fmokes copioufiy, and by degrees totally evaporates : By a gentler 
 fire, continued for fome time, it is changed into a whitifh calx ; which, on 
 railing the heat, melts into a yellowifh or reddifh glafs. Melted with Silver, 
 or the other malleable metals, it renders them hard and brittle. It deftroys 
 the magnetic power of Iron ; which other metallic bodies only weaken in pro- 
 portion to their quantity. It does not amalgamate, or not without great diffi- 
 culty, with Mercury : If a mixture of it with Silver and Copper be reduced 
 into fine powder, even thofe metals will not, in that flate, be adted upon by 
 Mercury (/&).-—— -In the human body, it a£ls as a virulent emetic and cathar- Medical ef- 
 tic ; and impregnates vegetable acids, as Vinegar and acid Wines, with thofe °f Anti- 
 virtues, almofl inexhauftibly. By Sulphur, and by calcination with Nitre, its d;fre ‘ 
 mahgmty is abated, and its emetic power changed into a diaphoretic one. As ft anC es. 
 foon as it is reflored to its pure metallic ftate, it refumes its virulence; which 
 may be again deftroyed, and again reflored, and almofl infinitely varied. 
 
 Hoffman has given an account of the different medicinal effedts of Antimony, 
 as depending on its different treatments. He obierves, (1.) That crude An- 
 timony, on account of the Regulus being corredled by the Sulphur, is not 
 only fafe, but in many cafes a medicine of great fervice, both for man and 
 other animals. (2.) That by fimple fufion, it acquires a degree of malignity ; 
 but a far greater if melted with half its weight of Nitre, which conlumes 
 
 nearly 
 
 (b) Regulus of Antimony with Mercury .] 
 Common Regulus of Antimony may be a- 
 malgamated with Quickfilver, by melting 
 the Regulus, and pouring it, in a {lender 
 ilream, into a confiderable proportion of 
 Mercury made almoft boiling hot: To pre- 
 vent any lofs of the Quickfilver; the velfel 
 may be covered with an iron-plate, and the 
 Regulus poured in through a perforation in 
 the plate. By this method, the union fuc- 
 ceeds more readily and perfectly, than when 
 water is made to boil upon the furface of 
 the Quickfilver, as Henckel diredls ; the 
 Regulus lofing of its heat, in palling 
 through the water, before it comes to the 
 Mercury. 
 
 A Regulus prepared from Antimony, by 
 the means of Iron and Chalk, unites readily 
 and perfectly with Mercury, by bare tritu- 
 ration with water, into a firm amalgam. 
 This difcovery was made by Mr. Pott, and 
 communicated in his Lithogeognofia . He ob- 
 ierves that four parts of Antimony, with one 
 of Chalk, and two or five parts of Iron, 
 yielded Reguli equally amalgamable ; and 
 that Marble and Quick-lime fucceeded 
 equally with Chalk ; but that Clay, Gyp- 
 
 fum, and other earths had no effedl. 
 
 There is one earthy fubllance which pro- 
 duces a very remarkable effeffc upon Anti- 
 mony; though neither the earth itfelf, nor 
 the change which the Antimony undergoes, 
 have hitherto been duly examined. The 
 earth, called caivk, is found in Lead-mines, 
 in whitilh, moderately compact and pon- 
 derous maffes : It is commonly fuppofed a 
 fpar, but differs from the bodies of that 
 clafs in not being ailed upon by acids. If 
 a lump of Cawk, of an ounce or two, be 
 thrown red-hot into fixteen ounces of melt- 
 ed Antimony, the fufion continued about 
 two minutes, and the fluid matter pour- 
 ed off ; “ you will have fifteen ounces, 
 
 “ like poliihed Steel, and as the moff re- 
 “ fined Quickfilver.” Pbil.Tranf. N° no. 
 I have feveral times repeated this experi- 
 ment with fuccefs : But having once varied 
 it by mixing the Cawk and Antimony toge- 
 ther at firft, a part of the Antimony was 
 converted into a dark black vitreous matter, 
 and part feemed to have fuffered little 
 change : On the furface of the mafs ap- 
 
 peared fome yellow flowers. 
 
 S 2 
 
 

 
 Metallic Bodies. 
 
 Antimony, nearly all the Sulphur, and leaves theRegulus bare. (3.) That Antimony, or its 
 L_, Regulus, mixed with common Salt, calcined over a gentle fire for feveral hours 
 
 Preparations. 
 
 Golden Sul- 
 phur. 
 
 and kept continually llirring, and afterwards edulcorated with water, yields 
 an affi-grey calx, which is fo fixed as to bear a melting heat, and proves a 
 mild and fafe diaphoretic, void of any malignant or emetic quality. (4.) That 
 Antimony, by calcination with a gentle fire, in an earthen veffel, in the open 
 air, changes into a calx, which melts difficultly, and which has no malignity. 
 (5.) That if this calx be melted with a ftrong fire into glafs, it becomes fo 
 adlive, that a few grains fhall occafion violent vomiting and purging, or even 
 mortal convulfions and inflammations. (6.) That the powdered Regulus, cal- 
 cined in a glafs-vial placed in land for feveral days, becomes a greyifh diapho- 
 retic powder-, which reduced into Regulus, by fufion with powdered Char- 
 coal, Nitre, and a little fat, proves again virulent. (7.) That when Anti- 
 mony is melted with one-fourth its weight of Salt of Tartar, the whole poured 
 into a mould, the lcoria feparated, and the more ponderous matter pulverized ; 
 the reddilh powder thus obtained, is falutary : But that when Antimony is 
 melted with three or four times its weight of Salt of Tartar, both the Scoriae 
 and the Regulus are virulent. (8.) That equal parts of Antimony and Nitre, 
 melted together, yield a virulent mafs ; but one part of Antimony, with two 
 or three of Nitre, an ufeful diaphoretic. (9.) That the Regulus, melted with 
 half its .weight of Nitre, continues emetic -, but that one part of the Regulus, 
 with two and a half of Nitre, becomes diaphoretic. (10.) That on melting 
 the diaphoretic calces with fat, Charcoal powder and Nitre, the virulent Re- 
 gulus is revived. And thus one preparation may be changed into another, a 
 falutary into a poifonous, and a poifonous into a falutary one. 
 
 The preparations of Antimony are extremely numerous. Lemery, in his 
 treadle on Antimony, defcribes no lefs than two hundred ; among which there 
 are many good, and many ufelefs ones. That gentleman was an excellent 
 workman, but an unhappy philofopher : We may depend on his operations, 
 
 but we are not to trull his theory. With regard to the antimonials, the greater 
 number even of the common preparations is unneceffary ; many of them dif- 
 fering little from one another, and all of them being either emetic or diapho- 
 retic. For my part, 1 fhould be fatisfied with two, the diaphoretic Anti- 
 mony and emetic Tartar. 
 
 Crude Antimony, as already obferved, is ufed for purifying the juices, and 
 refolvingobfiructions : It is given likewife to cattle, and employed in compc- 
 fitions for fire-works, and for the purification oi Gold. The preparations of 
 Antimony may be ranged, according to the general operations by which they 
 are produced, under four heads; thofe obtained by folution, by diftillation, 
 by fublimation, and by calcination. 
 
 If powdered Antimony be boiled in alcaline Lixivia, or Sope leys ; the Sul- 
 phur, and by the mediation of the Sulphur, a part of the Regulus, will be chf- 
 folved into a yellowifh red liquor. Any acid added to this folution precipitates 
 what the alcaiine liquor had taken up, in form of a yellowifh or reddiffi pow- 
 der, called Sulphur or golden Sulphur of Antimony : The powder which fettles 
 firft is grofifer and darker coloured than thofe which follow it appears of a 
 
 deep 
 
Metallic Bodies. 133 
 
 deed redd ifn brown, whilft that which fubfides laft is of a pale yellow. The Antimony. 
 tirft is alfo the mod adive. 
 
 There are fundry variations of this procefs, both in regard to the folution 
 and the precipitation. Some employ Lime-water for the menftruum : Others, 
 inftead of boiling the Antimony in a folution of alcaline Salt, melt the Anti- 
 mony with the Alcali, and boil the fcoria in water. Some precipitate with 
 one acid, and others with another. Some, that the medicine may with pro- 
 priety be called golden , perform the precipitation with a folution of Gold : 
 
 Others take a folution of Vitriol of Iron. A difference in the manner of pre- 
 paring the folution does not feem to affed the virtue of the medicine •, but a 
 difference in the acid ufed for the precipitation does ; different acids having 
 very different effeds upon Antimony : Thus whilft the marine renders it highly 
 corrofive, as in the butter of Antimony, and virulently purgative and emetic, 
 as in the Mercurius vitre precipitated from that butter-, the addition of the 
 nitrous deftroys the virulence of both preparations, and renders the Antimony 
 mildly diaphoretic. 
 
 All the antimonial Sulphurs are emetic and cathartic : Thofe which preci- 
 pitate fir ft are much more ftrongly fo, than the powder which falls laft: The 
 laft, precipitates, if they prove emetic once or twice, ceafe to have that effedt 
 upon continuing their ufe, and adt chiefly as diaphoretics ; and hence are 
 greatly to be preferred to the firft. Thefe preparations are powerful refolvents, 
 diaphoretics, purifiers of the blood, antifpafmodics ; of remarkable efficacy in 
 obftrudions of the vifcera, quartan agues, cutaneous and venereal diforders, 
 fuffocative catarrhs, leucophlegmatic and cachedic habits. The dole of thofe 
 of the laft precipitation is about fix grains : Two grains may be given to a 
 
 child of two years or even of one year old A powder is vended by theKermes mi- 
 
 Carthufian friars in Paris, at a confiderable price, as a fpecific againft fundry neral - 
 diforders-, commonly called poudre des charlreux, but by themfelves kermes 
 mineral. This is no other than a golden Sulphur of Antimony ; prepared by 
 digefting powdered Antimony in an alcaline ley, and at length boiling them 
 together; afterwards filtering the liquor, and fetting it by in a warm place, 
 till a reddifh brown Precipitate falls fpontaneoufly. 
 
 For diffolving the Regulus of Antimony without the Sulphur, the moft con- Butter of An- 
 centrated Spirit of Salt, or Aqua regis, is neceffary. For obtaining the folu- dmony. 
 tion in Spirit of Salt ; Mercury fublimate and powdered Antimony are mixed 
 together, and digefted in a glafs- retort placed in fand : The marine acid in 
 theSublimace forfakes the Mercury, and corrodes or diffolves the antimonial 
 Regulus; whilft the Mercury of the Sublimate unites with the antimonial 
 Sulphur. But the folution of the Regulus, thus effected, cannot be commo- 
 dioully feparated from the other matter but by diftillation : On increafing the 
 
 fire, the Regulus arifes, diffolved in the concentrated acid not into a liquid 
 form, but into that of a thick unduous fubftance like butter, hence called 
 butter of Antimony. The butter liquefies by heat ; and requires the cautious 
 application of a live coal, to melt it down from the neck of the retort. By 
 redification or expofure to the air, it becomes fluid, but ftill retains the name 
 of butter : The addition of water, either in its thick or fluid ftate, by diluting 
 the acid, precipitates the Regulus diffolved in it. The proportions of Subli- 
 mate 
 
*34 
 
 Antimony, 
 
 Mercurius 
 
 vitae. 
 
 Phiiofophic 
 Spirit of Vi- 
 triol. 
 
 Bezoar mine- 
 ral. 
 
 'Bezoardic 
 Spirit of 
 Nitre. 
 
 Clyffi of An- 
 timony. 
 
 Metallic Bodies. 
 
 ■ mate and Antimony commonly employed are, three parts of the former to one 
 of the latter: It is obfervable, that if Regulus of Antimony in fine powder be 
 mixed with Sublimate in the fame proportion, and the mixture prefied down 
 clofe in a narrow mouthed giafs ; the matter will in a little time grow hot 
 fmoke, effervefce, melt, and boil. There are various other methods of ob- 
 taining the butter of Antimony or a combination of the Regulus of Antimony 
 with marine acid ; as, by placing the Regulus in the receiver, and diftilling 
 over upon it a concentrated marine fpirit from Sea-lalt or Sal ammoniac and 
 Oil of Vitriol ; or mixing either crude Antimony or the Regulus with common 
 Salt, and diftilling with the addition of Oil of Vitriol, calcined Vitriol, or 
 fuch other fubftances as may extricate the acid of the Sea-falt. If the combi- 
 nations of Silver or Lead with the marine acid, called luna cornea and faturnus 
 corneus , be mixed with Regulus of Antimony and expofed to the fire, the acid 
 will forfake thofe metals, as well as it does Mercury, to unite with the Regulus. 
 
 There are fun dry preparations made from butter of Antimony, as (i.) Mer- 
 curius vita or pul-vis algarathi: This is no other than the Precipitate which falls, 
 upon mixing the butter with water. It is a violent and unfafe emetic. A 
 Precipitate obtained from the butter by means of highly rectified Spirit of 
 Wine, is faid to be more mild and fafe ; to procure, after its addon as an 
 emetic is over, fleep ; and during the fleep, to promote a fweat. Some em- 
 ploy an alcaline ley for the precipitant, and thus alfo obtain a medicine of lels 
 violent operation. (2.) Spiritus vitrioli philofophicus, improperly fo called, as it 
 neither contains any thing vitriolic, nor polfdTes any lingular properties that 
 may entitle it to the appellation phiiofophic : It is the liquor that remains after 
 
 the foregoing precipitation, rectified by diftillation. (3.) Bezoar mineral is 
 prepared, by gradually adding Spirit of Nitre to butter of Antimony placed in 
 a retort, fo long as any effervefcence enfues, diftilling off the fpirit, and cal- 
 cining the refiduum : Some cohobate the fpirit twice or thrice previous to the 
 calcination, and others employ frefh Spirit of Nitre in each cohobation : This 
 is entirely unneceflary if the nitrous fpirit was added at firft in fufficient quan- 
 tity, that is, till it ceafed to make any effervefcence with the butter. This 
 preparation may be made more commodioufly by mixing one part of the Mer- 
 curius vita with two and a half of Nitre, injeddng the mixture into a red-hot 
 crucible, and proceeding in the fame manner as for the calx called diaphoretic 
 Antimony. The Bezoar mineral made in either of thefe ways, proves in no 
 refpedt different from that calx. (4,) The fpirit diftilled in making the Bezoar 
 by the firft of the above methods, is an Aqua regis, commonly diftinguilhed 
 by the name of Spiritus nitri bezoar dicus. (5.) A lunar bezoardic is prepared by 
 treating the butter of Antimony with a folution of Silver in Aqua fortis inftead 
 of the acid by itfelf ; a folar bezoardic, by adding a folution of Gold to the but- 
 ter, and then proceeding with Spirit of Nitre as for the fimple Bezoar mineral ; 
 a martial , by ufing a folution of Iron in the nitrous acid, or mixing Iron with 
 the Regulus previoufly to the diftillation of the butter ; and a jovial , by adding 
 Tin to the Regulus. All thefe preparations are very infignificant. 
 
 The clyffi of Antimony are obtained, by mixing equal parts of Antimony 
 and Nitre, or of Antimony, Nitre and Sulphur, and injecting the mixture by 
 a little at a time, into a tubulated retort made red-hot ; a large receiver contain- 
 
M E'T a l l i c Bodies. 135 
 
 mg this or that diftilled water, being fitted to the retort : The water, thus Antimony. 
 
 impregnated with the nitrous and fuiphureous acid, is to be rectified in a glais ' — “" s - 
 retort. This liquor has no fingular qualities to recommend it, and may very 
 well be fpared : If wanted, it might be procured, without ufing any Antimony 
 ©r Nitre on purpofe for it, by colledting the vapour which arifes during the 
 deflagration in making diaphoretic Antimony. If the Nitre is omitted, and 
 the Antimony diftilled by itfelf, there arifes a fourifh water or weak Spirit of 
 Sulphur, commonly called acidum antimonii. 
 
 Some make a folution of the reguline part of Antimony, by applying the Flowers,, 
 bezoardic Spirit of Nitre to the crude mineral: The folution, diluted with 
 water, depofites a Mercurius vita, which when prepared in this manner is called 
 jicres antimonii fixiores. The flowers of Antimony, properly fo called, are pre- 
 pared by fubliming either the crude Antimony or the Regulus into a number of 
 aludels ; the fire being kept up ftrong, and a blaft of air impelled occafionally 
 by a pair of bellows upon the matter in the fubliming pot, to promote its eva- 
 poration. We have alfo flowers made by fubliming, with a gradual fire, a 
 mixture of Regulus of Antimony and Sal ammoniac, grinding the Sublimate 
 with the refiduum, and repeating the operation till nearly all the Regulus is 
 elevated. We often find three or four kinds of flowers in one fublimation, 
 differing from one another in their external appearance as well as in quality. 
 
 In fubliming the Regulus, there are commonly three forts; one of a mealy 
 whitenefs, one fparlding, and the third of a beautiful cryftalline appearance : 
 
 This laft is called Silver flowers of Antimony. Some flowers may likewife be 
 collected in detonating the mixture for diaphoretic Antimony in a tubulated re- 
 tort, The flowers made from crude Antimony with Sal ammoniac, expofed 
 to the air, run into a liquor called Oleum febrifugum. The antimonial flowers 
 are in general of great activity, and though recommended by fome as Arcana in 
 particular diforders, require to be ufed with great caution. 
 
 We have formerly feen, that after the diftiilation of butter of Antimony, thecinnabari 
 Mercury and the Sulphur, contained in the ingredients made ufe of for that 
 procefs, remain behind in the retort. This compound appears of a black co- 
 lour: Urged with a ftronger fire than that which elevated the butter, it fub- 
 limes into a red mafs called Cinnabar of Antimony. This Cinnabar has been by 
 many preferred to the common factitious Cinnabar, but on no juft foundation : 
 
 They both confift of Mercury combined with Sulphur; and the only difference 
 betwixt them is, that the antimonial Cinnabar contains fomewhat more Sul- 
 phur than the other, and hence appears of a darker colour. Some have been 
 accuftomed to fublime the antimonial Cinnabar a fecond time, with the addi- 
 tion of a little frefh Mercury, or of fome calcareous earth to abforb a part of 
 the Sulphur; and by either of thefe methods they obtain a Cinnabar equal in 
 colour and in every other refpedf to the common fort. Hoffman has expreffed 
 himfelf erroneoufly, in faying, that the Mercury in Cinnabar of Antimony is 
 fettered by the acid of the Sulphur, and that its revival depends upon the tak- 
 ing away of that acid : It is not the acid, but the whole fubftance of the Sul- 
 phur, which fetters the Mercury, and which muft befeparated, in order to its 
 revivification, by abforbent earths, Iron filings, or other ablorbents of Sul- 
 phur. A certain writer affirms, that a Cinnabar may be made from Mercury 
 
136 
 
 Metallic B o d i 
 
 e s. 
 
 though both 
 
 Calcination. 
 
 Glafs. 
 
 Antimony, and glafs of Antimony, and hence infers the exiftence of fulphureous particles 
 — -v — — ' even in the glafs. With me, the experiment did not fucceed, 
 crude Quickfilver and corrofive Sublimate were tried. 
 
 The Ample calcination of Antimony is performed, by fpreading the pow- 
 dered mineral in a flat ihallow pan, and keeping it over a gentle fire till 
 the Sulphur is diflipated, and the powder become grey : The powder fhould be 
 continually ftirred with a glafs rod or a tobacco-pipe, and if it happens to run 
 into lumps, it muft be taken from the fire and pulverized afrefli: The heat 
 ihould be flowly and gradually increafed, and continued till the matter, fmelt 
 to whilft red-hot, difcovers no fulphureous odour. This calx is neceffary for 
 making the glafs of Antimony : It may be reduced into Regulus by fufion 
 with inflammable fubftances, and the Regulus into crude Antimony again by 
 fufion with common Sulphur. It is obfervable, that though great part of the 
 Sulphur of the Antimony is diflipated in this operation, yet the calx weighs 
 more than the Antimony at firft:. Of the matter which exhales, fo much has 
 been colle&ed as to amount to one eighth of the Antimony. 
 
 Glafs of Antimony is chiefly prepared by fome particular perfons, at Am- 
 ite rdam and Rouen, who have furnaces contrived on purpofe for calcining 
 large quantities of Antimony with little expence of fuel. The glafs may be 
 eafily made, by urging the calx in a crucible with a ftrong fire, and throwing 
 in, towards the end, a little crude Antimony or Sulphur. I have obferved, 
 and I know of no one who has made the obfervation before me, that a calx of 
 Antimony, prepared with the utmoft care, will not yield any Glafs of itfelf, 
 without the accefiion of fome inflammable matter-, and that after refilling an 
 intenfe fire of fufion, it vitrefies immediately upon the injeftion of a little Sul- 
 phur or Antimony, a fmall portion of Regulus being at the fame time revived. 
 The Glafs turns out nearly of the fame reddifh brown colour whether Anti- 
 mony or Sulphur is ufed ; but when Borax is taken to promote the vitrifica- 
 tion, it proves of a light citron or amber yellow colour. When the vitrification 
 is completed, the Glafs is poured on a Copper plate, or into a Copper dilh, or 
 on a flat Hone. Some advife to ltir it in the crucible with an Iron rod, but all 
 Iron Inftruments fhould be avoided ; the Iron not only reviving a part of the 
 Regulus, but being itfelf alfo corroded and diflolved, fo as to render the Glafs 
 foul. The Glafs of Antimony is uled only for making other emetic prepara- 
 tions, as the emetic Wine, Syrup, Sapa, Oxyfaccharum, Aqua vitae, &c. 
 Some employ it for making the emetic Tartar ; boiling the powdered Glafs in 
 water with a proper quantity of Creme of Tartar, and infpififating the filtered 
 liquor. Some digeft the Glafs, reduced into fubtile powder, in frefli parcels 
 of diftilled Vinegar, till it no longer gives any tinge to the menftruum *, then 
 infpiflfate the feveral liquors together, and extra&a tindlure from the refiduum 
 with Spirit of Wine. The Glafs has alfo been call into drinking veflfeis, which 
 communicate an emetic quality to wines that are fuffered to ftand in them for 
 any confiderable time. 
 
 Equal parts of crude Antimony and Nitre mixed together, fet on fire and 
 fuffered to deflagrate in an Iron mortar, which may be covered with a perfo- 
 rated plate, or injected by degrees into an ignited crucible, yield a liver- 
 coloured mafs called hepar antimem , which pulverized and edulcorated with 
 
 5 water 
 
 Hepar. 
 
Metallic Bod'ie s. 137 
 
 water is named crocus metallorum . Two, three, or even one grain of either of Antimony. 
 
 thefe preparations occafion violent anxieties and vomitings; though a dog will l — — 
 
 bear a dram, and a horfe a whole ounce, without being apparently any other- 
 
 wife affefted than in having the alvine difcharge increaled. The emetic Wine, 
 
 emetic Tartar, and other medicines made from the Glafs, may alfo be made 
 
 from the Crocus. The Crocus is ufed in fome places for an eye-water called 
 
 Aqua ophthalmica quercetani. 
 
 With regard to emetic Tartar, the practice of cryftallizing it is very excep- Emetic Tari 
 tionable ; as the cryftals will by no means be uniform in ftrength, fome prov- tar ° 
 ing violently and others weakly emetic, and fome of them being mere cryftals 
 of Tartar, which have fhot without any antimonial impregnation at all ; the 
 liquor which remains after the cryftallization, evaporated to drynefs, yields a 
 mafs very different from the cryftals. I would therefore recommend, -whether 
 the Glafs or Crocus are made ufe of, the folution to be gently evaporated to 
 drynefs ; the matter to be kept conftantly ftirring, towards the end of the eva- 
 poration, as is commonly pradtifed in exficcating folutions of Ext alcaline 
 Salts; and the whole of the dry refiduum to be ground together for a confider- 
 able time in a ftone mortar. We fhould be well fatisfied of the ftrength of 
 emetic Tartar before we exhibit it, as there are fundry variations in its prepa- 
 ration, which vary its effedts : The ufe of the Crocus or Glafs, the manner in 
 which thefe have been made, their proportion to the cryftals of Tartar, the 
 quantity of water, the length of time that the codtion is continued, will all 
 influence the medicine. I have known fatal confequences from inattention to 
 the differences in emetic Tartars : A Dutch phyfician, who had been accuf- 
 
 tomed to an emetic Tartar prepared with Salt of Tartar, as defcribed by Mor- 
 ley in the Collett. Chym. Leydens, whofe dofe was ten, twelve, fifteen grains 
 and upwards, prefcribed a like dofe of emetic Tartar from a German fhop, by 
 which the patient vomited to death. I have known alfo three or four grains of 
 ftrong emetic Tartar prove mortal. 
 
 One part of Antimony and two and a half or three of Nitre, mixed toge- Diaphoretic 
 ther and deflagrated, yield a calx void of all emetic power, called diaphoretic Antimony. 
 Antimony. If the detonation is performed in a tubulated retort having a large 
 receiver, containing fome water, adapted to it ; both a clyffus of Antimony, 
 and antimonial flowers, may be obtained at the fame time. The calx is to be 
 freed from its faline parts by ablution with water: If the water be duly eva- 
 porated and fet to fhoot, it yields cryftals called antimoniated Nitre : If diftilled 
 Vinegar is added to the liquor, a white Precipitate falls, called materia perlata 
 or Magiftery of Antimony. Some make ufeof the diaphoretic Antimony without 
 edulcoration ; but this practice is not to be approved, the unwafhed calx con- 
 taining different faline matters, whofe proportions we cannot be certain of; as 
 the antimoniated Nitre, an alcaline Salt, a vitriolated Nitre produced from the 
 fulphureous acid and the alcaline bafis of the Nitre. Powdered Regulus of 
 Antimony, deflagrated in the fame manner with twice or thrice its weight of 
 Nitre, affords a calx not different in quality from the preceding, but diftin- 
 guilhed by the name of cerujfa Antimonii or Antimonium diaphoreticum regulinum. 
 
 Some think to improve the virtue of thefe calces by burning Spirit of Wine 
 upon them, qr diftilling it off, or treating them with Vinegar : But Spirit of 
 
 T Wine 
 
Regulus. 
 
 138 Metallic Bodies. 
 
 Antimony. Wine can have no effect, and Vinegar is more likely to deprave than to im- 
 prove the medicine. That the calces, as fome pretend, area mere earth, not 
 different from pounded tobacco-pipes, is apparently falfe, for we can presently 
 reduce them, by fufion with inflammable fluxes, into pure Regulus. 
 
 The martial diaphoretic Antimony or fpecific fiomachic ofPoterius, is prepared 
 by melting equal parts of Antimony and Iron filings, injecting upon them in 
 fufion thrice their weight of powdered Nitre, and alter the detonation is over, 
 edulcorating and drying the calx. The jovial diaphoretic Antimony or antiheffic 
 of Poterius, is made in the lame manner, from a mixture of Tin and martial 
 Regulus of Antimony, in the proportion of one part of Tin to four of the Re- 
 gulus. This preparation has no claim to antihectic virtues, nor indeed to any 
 falutary operation. 
 
 The fimple Regulus of Antimony is commonly prepared from equal parts of 
 Antimony, Nitre and Tartar, mixed together and injected into a red-hot cru- 
 cible : When the whole is thrown in, the crucible is to be covered, a ftrong 
 lire kept up for a quarter of an hour, and the matter poured out into a coni- 
 cal mould previoufly warmed and rubbed with greafe. The yield of Regulus 
 •will be larger, if the quantity of Nitre is diminiihed ; or if the Nitre and Tar- 
 tar are deflagrated together, in the proportion of one part of the former to two 
 of the latter, before their mixture with the Antimony : The Saks are reduced 
 by the deflagration into a black alcaline coal; this is the fubftance commonly 
 ailed by the chemifts for promoting the fufion of metallic calces and reviving 
 them into their metallic form, and hence is diftinguifhed by the name of black 
 flux. Some have been accuftomed to fave the expence of Nitre, by taking 
 Pot-afli or other alcaline Salts : The Regulus is in both cafes the fame. When 
 the matter is grown cold, the lcorias found on the furface are knocked off, 
 the Regulus reduced into coarfe powder, melted in a frelh crucible, and about 
 one fourth its weight of purified Nitre injedled upon it : This depuration may 
 be twice or thrice repeated with fmaller proportions of Nitre, till the fcoria 
 become femitranfparent and of an amber colour. The depuration with Nitre 
 is never to be omitted, whether the Regulus is prepared in thefe methods, or 
 in Kunckel’s more advantageous way, formerly mentioned, of calcining the 
 Antimony and reviving the calx. 
 
 The Regulus Antimonii tnedicinalis is impoperly fo called, as being only a 
 reddifh brown mafs, like the hepar Antimonii, without any thing of a reguline 
 or metallic appearance : It is named alfo febrifugum Craanii , panacea antimonii , 
 magnefia opalina, (Ac. There are various formulae of its preparation. Craan 
 takes five parts of Antimony, four of common Salt, and one of Salt of Tar- 
 tar; and after melting them together for a quarter of an hour, wit. a flrong 
 fire, pours the whole into a greafcd cone. Some phyficians in England pre- 
 pare a medicinal Regulus from Antimony and unpurified common Salt, with- 
 out the Salt of Tartar; and mix this Regulus with Gum guaiacum, againft 
 fcrophulous fvvellings and glandular obftrudtions. Hoffman on the other hand, 
 takes Salt of Tartar without Sea-falt, in the proportion of one part of the Alcali 
 to four of Antimony: and commends the Regulus fo obtained, as a fafe and 
 
 Medicinal 
 
 itegulus. 
 
 efficacious medicine. 
 
 4 
 
 The late profeffor Schulze ufed one part of Nitre to 
 
 four 
 
Metallic Bodies. 133 
 
 foul* of Antimony. All thefe preparations, I prefume, may be well fpared; Antimony. 
 and indeed they are already almoft out of fafhion. C-— v- — 
 
 The martial Regulusof Antimony is obtained moft commodioufly from four Martial Re- 
 parts of powdered Antimony, two parts of Iron nails or wire, and one part ofg ulus » 
 
 Nitre. The Iron, made red-hot in a crucible, foon melts upon adding the 
 Antimony ; after which the Nitre is to be inje&ed, the crucible covered, and 
 the matter, when brought into thin fufion, poured expedidoufly into a warm 
 greafed cone. The Regulus, freed from the Scoriae, is to be melted afreffi, 
 with about one-fourth its weight of Nitre, and this purification, if neceffary 
 repeated. If the Regulus retains any fuperfluous Iron, it will look greyifh, 
 fpongy, prove hard to break, and difficult of fufion : In fuch cafe, the fcori- 
 fkation of all the Iron by means of Nitre would be a tedious work •, but the 
 addition of a little crude Antimony or common Sulphur will abfoib it at once j 
 and the injection of Nitre will now foon complete the purification, and render 
 the Regulus of a fparlding white colour. The fcoriae are yellow and femi- 
 tranfparent like amber : If the quantity of Nitre has not been too large, they 
 prove an exceffively ftrong fiery Alcali, diftinguifhed by the name of Niirum Cauftic Nitre* 
 caujlicum. The yellow fcoriae, which leparate in the depuration of the fimple 
 Regulus with Nitre, are likewife alcaline, but want the cauflicity of thefe: 
 
 The fcoriae produced from the martial Regulus, by calcination with Tartar, 
 take fire on being expofed to the air. If either Regulus, after due purifica- 
 tion, be haftily poured into the mould whilfl in exceeding thin fufion, and if 
 the quantity of fcoria covering the furface is confiderable, the Regulus, when Ste ]] atC( | 
 grown cold, exhibits the appearance of a ftar upon the top. For producing guius. 
 this appearance, there is no occafion for any particular fort of Antimony, or 
 any particular Iron, or any particular conftellation, or feafon, or weather, as 
 many have idly imagined •, the whole depending upon the circumftances above- 
 mentioned. If the martial Regulus be melted with an equal quantity of puri- 
 fied Copper, the mixture, inftead of a ftar, exhibits a net on the furface, called 
 
 rete vulcani There are fundry compound Reguli of Antimony, venereal , 
 
 jovial , folar, &c. prepared either by barely melting the Regulus with other 
 metals, or employing the metal in the precipitation of the Regulus at firft. 
 
 Different metals abforb different quantities of Sulphur, and hence require to 
 be taken in different proportions to the Antimony : Thus, of Iron we take 
 half the weight of the Antimony, but of Copper an equal weight, and of Lead 
 twice as much: Tin does not eafily, in any proportion, precipitate the Regu- 
 lus. The fcoria with Tin flow the eafieft of all, next thofe with Silver, then 
 the venereal, after thefe the martial •, the moft difficultly fufible of ail are the 
 
 faturnine The fimple Regulus is caft into cups, which like thofe made 
 
 from the Glafs communicate an emetic quality to wines •, and into pills, like 
 fhot, which prove ftrongly purgative, and do not lofe their virtue in palling 
 through the body •, whence their name pilula perpetua. 
 
 There are various tin&ures of Antimony, which fome have fondly imagined Antimonia! 
 to participate of folar, venereal, antimonial and other impregnations. They tin&ures, 
 appear to be all no other than fimple alcaline tin&ures ; their colour proceed- 
 ing from the oily matter of the Spirit of Wine heightened by thecauftic Alcali. 
 
 Spirit of Wine confifts of an Oil highly attenuated and combined with water 
 
 T 2 into 
 
140 Metallic Bodie s." 
 
 Antimony, into one Seemingly homogene liquor : If the mod; highly rectified i'pirif, which 
 exhibits no mark of any phlegm, be employed for making thefe tindtures, it 
 will now yield in diftillation a good quantity of water; the Oil, before com- 
 bined with that water, having been ablorbed by the Alcali. II cauftic alcaline 
 Salt alone, be poured hot into rectified Spirit, and the mixture digefted for 
 Some time, a tindlure will be obtained, not diftinguifhabie from the antimo- 
 nial. If Sulphur be added in either cafe, the tindlure will receive a consider- 
 able take and fmell from that ingredient. The common tincture of Antimony 
 is made from the Scoris of Antimony-, and the tinfiura antimonii acris or Re- 
 gulina , from the nitrum caufticum. There is nothing remarkable in the prepara- 
 tion ; the matter being only put as hot as pofiible into the Spirit, before it can 
 imbibe any moifture from the air, and the mixture digefted till the Spirit ap- 
 pears Sufficiently tinged. 
 
 V. ARSENIC. 
 
 Arsenic. 
 
 THE chemifts have formed various conjectures about the nature of this Sin- 
 gular concrete ; but have not been able to determine what it really is, or 
 to what clafs of bodies it belongs. They have called it Sulphureous, undtuous. 
 
 mercurial, a mineral juice, &V. without foundation. Boerhaave, in his Ele- 
 ment a Chemise, ranks it under the head of Sulphurs, and fays it approaches 
 nearer to the nature of Sulphur than of any other known mixt : It wants 
 however the peculiar qualities by which Sulphur is diftinguilhed. Stahl, 
 with greater probability, fuppofes it to be of a faline nature. In Some of 
 its ftates, it apparently pofleflfes properties attributed to Saks alone; but in 
 other ftates, it is as obvioufly metallic. 
 
 General pro- White Arfenic, or Arfenic ftridtly fo called, is a moderately heavy, com- 
 petes, padt, hard, brittle concrete ; of a cryftalline or vitreous appearance ; gradually 
 changing, from expofure to the air, to a milky hue like that of Forcelane, 
 and at length to the opake whitenefs of white enamel. The larger mailes pre- 
 serve their transparency longer than the lmall ; in a dry, longer than in a 
 moift air. 
 
 in the fire, In the fire, it neither burns, nor perfedtly melts ; but totally and readily ex- 
 hales, in thick fumes, of a Strong fetid Smell refembling that of Garlic. The 
 fumes, caught in proper veftels, condenfe, either into cryftalline mafles again, 
 or into a white powder ; according as the receiver is lefs or more removed from 
 the heat. 
 
 metallized by Mixed with inflammable matters, and expofed to the fire in a retort or 
 phlogifton. other like veflel, it afiumes a metallic appearance. In this ftate, it greatly re- 
 fembles Regulus of Antimony ; being, like that femimetal, of a bright Spark- 
 ling whitifh colour, a plated or leafy texture, and very brittle: But its white- 
 nefs loon changes in the air to a dark blackifh hue. It Rill continues volatile, 
 as in its unmetallic form : It burns, and calcines in the fire, and Sublimes into 
 white Arfenic as at firft. 
 
 Solution in Arfenic reduced into fine powder, and boiled in fifteen times its weight of 
 water, water, totally difTolves. If the Solution be evaporated a little, the Arfenic 
 fhoots, on cooling, into cryftals; which frequently have a yellowifh tinge : 
 
 The 
 
Metallic Bodies. 141 
 
 The entire cry ftals are not taken up again by boiiing water, but when finely Ar se vic. 
 pulverized, they diffolve as at firft. The folution has a naufeous tafle, but ' — — v — — j 
 not aTaline iharpnefs. 
 
 Arfenic diffolves both in acid and in alcaline liquors, but makes no effer- in acids arud 
 vefcence with either: In fixt alcaline Lixivia it diffolves very plentifully, in Nealies, 
 acids more fparingly. Arfenie in its femimetallic form, called Regulus, is 
 eafier of folution than the white Arfenic or calx. 
 
 Powdered white Arfenic being digefted with Oil of Vitriol, and the liquorPhasnomena 
 di flilled off in a retort; there arofe at Jaft a tranfparent Sublimate like pure^d 1 ^ cil ^ erent 
 Glafs, but which, loft its tranfparency in a few days in the air, and became 
 opake like the Arfenic by itfelf. If the fixation of Arfenic is applicable to any 
 ufeful purpofes, the prefen t experiment promifes means of effecting it : For 
 the Arfenic remaining in the retort after the fublimation, fuftainedan open fire 
 without fuffering any lenfible alteration •, and probably it might be rendered 
 ftill more fixed by repeating the abftradion offrefhOil of Vitriol. 
 
 One part of white Arfenic being difiolved in two of Oil of Vitriol, and one 
 part of Borax added to the mixture, a ftrong effervefcence enfued, and whilft 
 the matter continued hot fome fine capillary flowers as it were, like flowers of 
 Borax, appeared upon the upper part of the Glafs. By degrees, the liquor 
 grew more and more clear and tranfparent ; but on cooling, acquired the colour 
 and confiftence of Venice Turpentine. The mafs liquefied, in the fame man- 
 ner as Turpentine, on applying heat ; but the air foon rendered it white, tmv 
 bid, and untranfparent. 
 
 Two drams of Arfenic being boiled in two ounces of good Spirit of Nitre, 
 till greateft part of the fpirit had exhaled ; and two ounces more of the acid 
 being then added, and the whole well ftirred together, the Arfenic totally dif- 
 folved. The folution, evaporated a little and fet to cool, yielded feveral fmall 
 quadrangular cryftals ; and the uncryftallized liquor looked like a pretty thick 
 folution of gum Arabic. Henckel obferves, in his Pyrit-ologia, that Arfenic 
 forms a gum-like fubftance with Spirit of Nitre-, but does not mention the 
 procefs. It was in conlequence of this hint that I rhade the two preceding 
 experiments. 
 
 A folution of Arfenic in pure water changed Syrup of Violets green, but not With various 
 till they had ftood together for feveral hours It made no effervefcence with laline liquors, 
 any faline liquors, acid or alcaline. Nor did I obferve that any precipitation 
 enfued, as a certain learned author fays there does, upon mixing with it Oil of" 
 
 Tartar per deliquium, Oil of Vitriol, or Aqua fortis. Oil of Tartar fcarce 
 occafioned any fenfibie cloud ; but Spirit of Sal ammoniac threw down a little 
 Precipitate. There was no precipitation or change upon mixing it with folu- 
 tions of vitriolated Tartar, purified Nitre, common Salt, Sal mirabile. Alum, 
 
 Borax, Sal ammoniac, and the faline concrete called fixt Sal ammoniac. It 
 precipitated almoft all metallic folutions, but fome of them fo {lowly, that an 
 incurious orhafty obferver would have pronounced there would be no precipi- 
 tation. Solution of Gold fuffered no change at firft from the admixture o{ the 
 arfenical folution ; but on {landing for twenty-four hours, it let fall a yellow 
 Precipitate, like Aurum fulminans. Solution of Silver grew immediately tur- 
 bid and bluifh; and in twenty-four hours depofited a dark brownifh grey Pre^ 
 
 emirate* 
 
14 2 Metallic Bodies, 
 
 Arsenic, cipitate. A folution of Iron in Aqua fortis continued at firfl clear; but on 
 
 U — landing for twelve hours, a fmall quantity of a fubtile yellow powder fub- 
 lided. A folution of Copper in Aqua fortis gave a whitifh calx ; and the 
 bluifh liquor Handing above it turned at laft green. Solution of Tin in Aqua 
 fortis was very copioufly precipitated. Solution of Lead in Aqua fortis fuf- 
 fered no change at firft, but on Handing yielded a plentiful Precipitate. So- 
 lution of Mercury in Aqua fortis let fall a plentiful flaky Precipitate ; on the 
 furface of which were obferved, next morning, fome particles inclining to 
 yellow. Solution of Mercury-fublimate, of Copper in Aqua regia, of Zinc in 
 Aquafortis, and ofRegulus of Antimony, continued clear and fuffered no 
 precipitation. Bifmuth diflolved in Aqua fortis is copiouflv precipitated by a 
 large addition of the arfenical liquor, but not at all by a fmall one. Solution 
 of white Vitriol yields a yellow powder; of green Vitriol, a thick yellow Preci- 
 pitate; but that of blue Vitriol depofites very little. Solution of Sugar of 
 Lead, and folutions of Sulphur made both with Quicklime and with fixed al- 
 caline Salts, are copioufly precipitated by the arfenical liquor : The fulphureous 
 folutions are precipitated even by a tindlure made from Arfenic with highly 
 rectified Spirit of Wine ; from whence it appears that vinous fpirits diflfolve 
 fome portion of this concrete. The liquor filicum , mixed with the watery folu- 
 tion of Arfenic, coagulates on Handing. I likewife diflolved Arfenic in Oil of 
 Vitriol, Spirit of Nitre, Spirit of Salt, Oil of Tartar per deliquium, and Spi- 
 rit of Sal ammoniac ; and mixed the acid folutions with alcalies, and the al- 
 caline folutions with acids. No precipitation enfued in any of thefe mixtures, 
 except two ; namely, when Oil of Tartar was dropt into the folution made by 
 Spirit of Salt, or Spirit of Salt into that made by Oil of Tartar : In both 
 thefe cafes a precipitation happened on Handing, moH readily and plentifully 
 in the laft. 
 
 With IVfer- If Arfenic be mixed with Mercury-fublimate, and the mixture expofed to 
 
 cury-fubli- the fire in a retort, the Sublimate will be deflroyed, or refolved into its con- 
 ftituent parts. Its acid quits the Mercury, and unites with the Arfenic : And 
 there diflils a Butter or Oil of Arfenic, that is a folution of the Arfenic in the 
 marine acid ; followed by the revived Mercury. We may judge from hence 
 how little foundation there is for the common report that Mercury-fublimate 
 is adulterated with Arfenic : It is plain that they cannot be united together by 
 fublimation, and Arfenic cannot be mixed afterwards with the mafs, as w r e 
 always meet with it in cakes. The method propofed for detecting the abufe, 
 if the abufe fhould be practicable, is likewife erroneous : It is fuppofed, that 
 Sublimate mixed with Arfenic will turn black with alcaline Lixivia, and pure 
 Sublimate not : But Arfenic by itfelf flrikes no blacknefs with alcalies, and 
 fome pure mercurial Sublimates do, probably from their being fuperfaturated 
 with Mercury. 
 
 With Nitre. White Arfenic makes no deflagration with Nitre ; but extricates the acid of 
 the Salt in a remarkable manner. If two parts of Nitre and one of Arfenic be 
 committed to diflillation in a retort, and fome water placed in the receiver to 
 promote the condenfation of the fumes ; a nitrous fpirit will be obtained, far 
 more volatile, fubtile and penetrating than common Spirit of Nitre, and of a 
 beautiful blue colour. This fpirit requires to be kept in vefiels very clofely 
 
 Hopt : 
 
Metallic Bodies. 
 
 *43 
 
 ftopt: If the air is admitted, its volatile vapours foon efcape, and all its co- Arsenic* 
 lour vanifhes(f). A part of the Arfenic arifes diffolved in the fpirit, as ap- v — 
 pears from the liquor making Copper white : What remains, along with the 
 alcaline bafis of the Nitre, proves confiderably more fixed in the fire than 
 Arfenic by itfelf. 
 
 Arfenic is detained alfo in the fire by common alcalies and earths, and may With alcali<$ 
 be converted along with them into a true Glais : Thus if Arfenic be diffolved ^J“ reowa 
 
 by boiling in a iblution of alcaline Salt, the liquor infpiffated, the dry matter 
 mixed with powdered Flint, and urged with a flrong fire as for making com- 
 mon Glafs, they will all vitrify together. Lemery relates, that in divers ope- 
 rations upon Arfenic in glafs veflels, there is often met with a vitrified mat- 
 ter, not diflinguifhable from the common Glafs of which the veffel is made, 
 except by its being a good deal more brittle. I have often obferved fuch a fub- 
 ftance myfelf; but it was only a clear cryftalline Arfenic, and not a true 
 Glafs. 
 
 Arfenic unites in fufion with all the metals ; commonly promotes their full- With me£a ^ 
 bility, and renders them hard and brittle ; and changes the coloured ones 
 white. In a flrong fire, a part of the Arfenic, evaporating, generally carries 
 off a part of the metal, efpecially of the imperfedt metals •, and the remainder 
 
 of the metal., calcining, vitrifies with the Arfenic. Lead forms 
 
 with Arfenic 
 a hya- 
 
 (/) Arfenic with Nitre.] Regulus of Arfe- 
 nic deflagrates ftrongly with Nitre : The 
 Calx or white Arfenic does not fenfibly de- 
 flagrate, but makes a confiderable ebullition, 
 and if the operation is performed in open 
 veflels, alcalizes the Salt. A large portion 
 of the Arfenic remains united with the Al- 
 cali, into a faline concrete j which deli- 
 quiates in the air, and diflolves in water in- 
 to a vifcous liquor, excepting a little flaky 
 matter, which refills both liquid menftrua 
 and fire. The arfenicated Alcali melts 
 eafily into a kind of pellucid glafs ; which, 
 continued in the fire, emits copious fumes, 
 and becomes more and more opake, and 
 milky, and difficult of fufion— — —The fame 
 kind of arfenicated Salt is obtainable by 
 combining white Arfenic with the common 
 fixed alcalies. 
 
 When Arfenic and Nitre are diftilled in 
 clofe veflels ; the Arfenic remains combined 
 with the Alcali of the Nitre, into the ap- 
 pearance of a perfedl neutral Salt; which 
 diflolves in water, does not liquefy in the 
 air, (hoots into regular cryftals, makes no 
 change in the colour of Syrup of Violets, 
 nor any effervefcence with alcalies or acids. 
 It neverthelefs precipitates mod metallic fo- 
 lutions made in acids, its Alcali uniting 
 with the acid, and its Arfenic with the me- 
 
 tal. Urged with a flrong fire in clofe vef- 
 fels, it fuffers no change : Even the addi- 
 tion of vitriolic acid does not difunite the 
 Arfenic from the Alcali. Laid on burning 
 coals, its compofitiorc is inftantly refolved # 
 the Arfenic reviving and evaporating. 
 
 The arfenical Calx is found likewife to 
 expel the nitrous acid from its combination 
 with the bafis of Sea-falt, with common fixt 
 alcalies, with volatile alcalies, and with ab- 
 forbent earths ; though incapable of ex- 
 pelling the weaker acid of Sea-falt from any 
 of thefe. After the expulfion of the nitrous 
 fpirit, the Arfenic remains always combined 
 with the Alcali or earth into a nutral (aline 
 concrete : It may even be transferred from 
 one into another, from volatile alcalies into 
 abforbent earths. The Arfenic is not to be 
 difunited from the earths, any more than 
 from fixed alcalies, by the flrongeft fire in 
 Clofe vpflels, but readily exhales in open 
 ones on the contadf of inflammable matter. 
 Hence certain ores, which £mit no arfenical 
 fumes by flrong calcination per fe in the 
 common method, on the addition of a little 
 charcoal yield abundance. 
 
 The foregoing obfervations are drawn 
 from a curious fet of experiments, by Mr. 
 Macquer, in the French Memoirs for the 
 years 1746 and 1748. 
 
144 - Metallic Bodies, 
 
 Arsenic, a hyacinth coloured Glafs, which proves a more powerful flux for earthy, and 
 L. — ■ > other refrabtory bodies, than the pure glafs of Lead. 
 
 Iron may be combined with Arlenic, by mixing the Arfenic with fixt alca- 
 line Salt and fome inflammable matter, as Sope, powdered Charcoal, Tartar, 
 &V. ft ratifying this mixture in a crucible with thin Iron plates or Iron filings, 
 fitting on the veflel a cover with a fmallhole in it, giving at firft a gentle fire 
 fiuch as the Arfenic by itfelf could bear, and then raifing the fire as expediti- 
 oufly as poflible, till the matter is brought into fufion ; or by mixing Arfenic, 
 Tartar, and Iron filings together, injebting them into a crucible ftrongly 
 heated, and pouring out the matter as foon as it appears fluid. Thus we ob- 
 tain an arfenicated Iron, hard, brittle, and whitifh. 
 
 Copper, combined in like manner with Arfenic, becomes white ; and re- 
 tains fome degree of malleability, efpecially if the proportion of Arfenic is not 
 too large, or if the compound is melted once or twice with Tartar and Borax. 
 An over-proportion of Arfenic makes the Copper not only brittle, but of a 
 dark colour, or liable to turn black on expofure fora few days to the air. The 
 workmen have different methods of preparing white Copper for mechanic ufes. 
 Some take equal parts of Copper and Arfenic, with a little Silver, as one part 
 of Silver, precipitated from Aqua fortis after quartation, to fixteen of the Cop- 
 per; ftratify them together, cement in aclofe crucible, and then raife the fire 
 to fufion. Some barely melt the Copper with Arfenic fixed by Nitre. Some, 
 inftead of white Arfenic, take yellow or fulphurated Arfenic (of which here- 
 after) and fublime it from a good quantity of common Salt : Of this Sublimate 
 they injebt a little upon melted Copper, which generally receives from thence 
 a very beautiful white colour. Some ftratify and melt the Copper with fixed 
 Arfenic and a little Luna cornea. Others add a little Zinc ; and the more 
 expert artifts, inftead of Copper, ufe Brafs. Thefe white metals are made into 
 buckles, candlefticks, and different kinds of ornamental furniture ; but are 
 never to be ufed for any veffels defigned for containing foods or liquors. 
 
 Arfenic de'oafes the colour of Silver, renders the metal brittle, and in part 
 volatilizes it. Silver melted in a clofe veflel with Arfenic and a little Sulphur, 
 forms a red compound, in fome meafure refembling the red Silver-ore. The 
 arfenica'l Sublimate obtained from that ore, ftrongly heated in a clofe Silver- 
 box, penetrates the metal, and renders it quite' porous. Silver cemented with 
 pure Arfenic, remained brittle and pulverable after the Arfenic had been difli- 
 pated by gentle calcination. 
 
 Tin melted with Arfenic is foon changed in part into a calx ; and both the 
 calx and the uncalcined part retain no (mail proportion of the Arfenic. The 
 Tin, thus arfenicated, appears of a fparkling white colour, and plated texture, 
 greatly refembling Zinc. Hence fome have imagined it to be a true Zinc ; 
 though the intrinfic properties of this compound are entirely different from 
 thofe of that femimetal. 
 
 Lead melted with Arfenic, begins to boil and fmoke in a lefs degree of heat 
 than is neceflary for producing that effebt upon pure Lead. A part of the 
 Lead evaporates, part runs into a fufible faffron yellow glafs, and what retains 
 its metallic form proves brittle and of a dark dufky colour. 
 
 Gold 
 
Metallic Bodies, i 4J 
 
 Gold itfelf is not only rendered brittle and deprived of its colour by Arfe- Arsenic, 
 
 nic, but volatilized : If the mixture be haftily urged with a ftrong fire, a part — * * 
 
 of the Gold fublimes. 
 
 Arfenic has different degrees of affinity with the different metals. It for- Affinities witlt 
 fakes Silver to unice with Lead, and hence in running down the arfenical Sil- metals, 
 ver-ores, the workmen commonly add a large proportion of Lead to abforb 
 the Arfenic. In like manner, it quits Lead for Tin, Tin for Copper, and 
 Copper for Iron : White Copper melted with Iron filings, recovers its original 
 redtiefs, the Arfenic being transferred into the Iron. Copper has a greater 
 affinity with Mercury than it has with Arfenic: Mercury amalgamated wi:h 
 
 white Copper, takes up only the pure Copper, the Arfenic being rejected to 
 the furface. Arfenic is more eafily feparable from all the metals than Sulphur 
 is: Though Sulphur is not rapacious, or apt to volatilize them, like Arfenic, 
 it adheres to them much more ftrongly. 
 
 Arfenic is employed for fundry mechanic ufes ; bythedyers, as an ingredient Ufes. 
 tn the competitions of fcarlet and other fine reds ; by the girdlers and pin- 
 makers, for whitening their Brafs or Copper; by the goldfmiths, for enamel- 
 ling; by the glafs-makers, for promoting the fufion of the fritt, and the clear- 
 nefs and tranfparency of the glafs ; by the porcelane- makers, in white glazings ; 
 by the preparers of compound metals, for communicating a Silver whitenefs 
 to Copper; by the aflayers, it is ufed, in the form of glafs, for promoting the 
 fcorification of refractory ores which participate of Tin and Antimony, and 
 which will not work off' but run into lumps in the cupel. I know an artiff Arfenical 
 who prepares a beautiful metal, like the fineft Steel, by melting caff Iron with compound 
 Arfenic and Glafs, and adding a little Tin during the fufion : The beauty of we d “ 5 ’ 
 the metal depends in great meafure upon the proportions. In Vienna, a 
 metal is made for ornamental ufes, reiembling the fineft Silver, from Iron, 
 
 Tin, and Arfenic; perhaps with the addition oi a little Copper. Arfenic is 
 ufed alfo in folders, or for uniting Iron with Tin, in fome places in the making 
 of tinned Iron plates. 
 
 Arfenic is a moft violent poifon to all animals; unleis the wolf fhould be Medical hif 
 an exception, who is faid, probably without fufficient foundation, to be only tor y- 
 purged by it. The utmoft caution is neceflary, in all operations upon Arfenic, 
 to avoid its fumes: It is on account ol the danger attending luch operations 
 
 that this mineral has hitherto been fo little examined by the chemifts. The 
 deftroying of rats, mice, or other domeftic animals, by means of Arfenic, is 
 full of danger; the operation of the poifon being fuch, that great part of it is 
 difeharged, and the animal induced to drink : Hence foods, liquors, and the 
 provender of cattle, have too often received a poifonous taint. It we cannot 
 catch thofe animals, we may neverthelefs be cleared from them by much fafer 
 means than the ufe of Arfenic : Frefh nightfhade is their enemy. If the juice 
 of the leaves or berries of that plant, or the diffilled water of the frefh herb, 
 be made into pellets with meal; the rats, without tailing the pellets, will for- 
 fake the places where they are laid. 
 
 With regard to the effefts of Arfenic in the human body ; a naufea, ficknefs 
 and reaching commonly enfue in about half an hour after taking it ; followed 
 
 U by 
 
146 Metallic Bodies. 
 
 Arsenic, by violent vomitings, hiccups, and pains in the ftomach and bowels: Con- 
 vulfions and palfies of the limbs prefently fucceed, with intenfe heats, cold 
 fweats, palpitations of the heart, extreme anxiety, reftleftnefs, proftradon of 
 ftrength, third and drynefs of the mouth and throat, lofs of reafon, and at laft 
 death. If the quantity taken has been confiderable, the ftomach and inteftines 
 are often found upon diffedtion corroded or perforated; though in general the 
 patient expires, before the adtion ofthepoifon has proceeded to fuch a length. 
 There are many poifons which adt by coagulating the juices ; but the operation 
 of Arfenic is erroneously luppofed to be of this kind : Arfenic rather liquefies 
 
 than coagulates the blood, and makes no change in its colour: Of milk, fa- 
 liva, and other animal' juices, it rather prevents than promotes the coagula- 
 tion. It is better to acknowledge our ignorance, than to advance groundlefs 
 conjedtures. 
 
 Antidotes, Several fubftances have been propofed as antidotes to this poifon. Thofe 
 who imagine Arfenic to be an Alcali, recommend acids and thofe who ima- 
 gine it a corrofive acid, diredt alcalies for counteradling its effedts : But Arfe- 
 nic is apparently neither one or the other. If rock Cryftal, or Bezoar, or the 
 roots of the elder-tree, by fome flrongly recommended, have feemed to do 
 fervice where Arfenic had been taken *, it was not on thofe ingredients, but on 
 the oils or fats ufed along with them, that the good efFedts of the medicine 
 depended. Oils, fats, warm fat broths, frefh butter, milk, taken plentifully 
 and repeatedly, are the only antidotes ; both for obtunding the force of the 
 Arfenic, and promoting itsdifcharge by vomit. If the vomiting does not freely 
 fucceed by the liberal ufe of thefe kinds of fubftances, fome mild emetic muft 
 be called in aid •, the expulfion of the poifon being a principal point. The 
 more threatening fymptoms being thus removed, oily glyfters, and a gentle 
 laxative are neceftary, to obtund and evacuate fuch part of the Arfenic as may 
 have pafted into the inteftines ; after which, the ftrength is to be recruited by 
 proper analeptics. 
 
 Chemiftry is capable of converting fundry poifons into medicines : Thus 
 
 the virulent antimonial Regulus is changed by that art into the mild diaphoretic 
 Antimony ; the violently corrofive Sublimate of Mercury, into the mild Mer- 
 curials dulcis. Some have been hence induced to imagine, that Arfenic alfo 
 might be corredied and rendered fafe ; and have even ventured to put fo dan- 
 gerous a fpeculation in pradlice: A preparation of Arfenic with Nitre has 
 
 been adlually fold by certain people about Berlin and in other places, under the 
 title of a fpecific febrifuge. But Arfenic, however prepared, continues Arfenic 
 ftill : We can mitigate and obtund, but we cannot deftroy its power. See 
 Stahl’s Mcnfts novembris , entitled Anchiater five venenum pro remedio venditum. 
 Ffi'eas when There are many examples of even the external application of Arfenic, pro- 
 externallyap- during dangerous confequences : Thus Hildanus mentions great debility, a 
 
 ,plkd, high fever, delirium, anxiety, palpitation of the heart and tremor of the limbs, 
 
 from fcarcely a grain of Arfenic applied to an ulcer in the foot. Some arfeni- 
 cal preparations have neverthelefs been recommended againft cancers and can- 
 cerous fores : And Arfenic itfeif has been worn on the pit of the ftomach in 
 times of the plague, as if one poifon was to be driven out by another. The 
 celebrated Dr. Mead has fhewn, that the ufe of Arfenic as an antipeftilential, 
 
 proceeded 
 
Metallic Bodies, 1 4.7 
 
 proceeded from an erroneous opinion of its being the fame with the fubftanCe Arsenic. 
 recommended in that intention by the Arabians under the name of darfird : The 
 darfini of the Arabians was no other than Cinnamon, though fuppoled, from 
 the affinity in found, to have been Arlenic. 
 
 Cafes frequently happen, in which we are called upon to determine whether Marks for dif- 
 a particular fubftance be Arfenic or not; as when powdery matters are found tinguifliing in 
 in the ftomach of thofe who are fufpedled to have died by poifon. Arfenic, in 
 a folid form may be ditlinguiflied, by its yielding, in the lire, white fumes and 
 a garlic fmell and by its whitening Copper. This laft trial is moil cotnmo- 
 dioufty made, by placing a little of the powder betwixt two clean, polifhed 
 copper-plates, binding the plates firmly together with wire, clofing the juncture 
 all round with a good lute, and then heating them red-hot. We may try alfo 
 whether any reguline or femimetallic matter is obtainable, by means of Tartar 
 and Suet. Arfenic diffolved in liquors is much more difficultly difcovered ; 
 and I can fcarce propofe any thing in this view, befides the experiments on 
 folution of Arfenic formerly related. But I forbear to fay any thing further 
 on this head, left, in endeavouring to difcover Arfenic, I ffiould furnifh means 
 for rendering it lefseafily dilcoverable. 
 
 The principal preparations of Arfenic are, fixed Arfenic and th: arfenical Preparations* 
 magnet. Fixed Arfenic is made by gradually injecting powdered Arfenic into 
 melted Nitre, commonly in the proportion of one part of the former to two 
 of the latter: When the ebullition is over, the crucible is covered, the matter 
 kept melted for a little time with a ftrong fire, and afterwards edulcorated with 
 water. The arfenical magnet is a mixture of equal parts of pure white Arfe- 
 nic, Sulphur, and Antimony, reduced feparately into fine powder, then 
 mixed, put into a glafs body fet in fand in a crucible, and urged with a very 
 gradual fire, till the matter is melted into a red vitreous mafs refembling a deep 
 garnet or ruby. We muft be cautious in handling this arfenical glafs, as a 
 wound received from it may be dangerous. 
 
 Pure cryftalline white Arfenic is never found native in the earth. A pow- Natural Hit 
 dery white Arfenic is now and then met with in fome of the Bohemian and tory. 
 
 Saxon mines ; though even this feems to be not a natural Arfenic, but to have 
 been feparated and fublimed from the ores, by the wood fires made in the 
 mines for burfting the mafies of ore. It is obfervable, that Saxony, of all 
 countries in the world, is the richeft in arfenical ores ; and that the richeft Sil- 
 ver-ores abound with Arfenic. 
 
 Some of the proper ores of Arfenic are of a whitifh, and others of a blackiffi 
 colour, and both forts have more or lefs of a fparkling metallic afpeift : The 
 firft are called white Pyritae, or mijj'pickel ; the iatcer fliegenjieinertz. They con- 
 lift moftly of Arfenic, blended with a confiderable proportion of earthy or 
 ftony matter, but with little if any admixture of any other metallic body. 
 
 The preparation of Arfenic was difcovered only about two centuries ago. Preparatiotrof 
 The ancients were unacquainted with our Arfenic ; their a,p<niuxw or y.qv be- white Arfenic. 
 ing our orpiment. The greateft quantities are prepared at Geyerfberg, near 
 the village Ehrenfriederfdorf, in Milnia, from ores brought thither from 
 Schneeberg and other Saxon mines. The ore is thrown into a furnace refem- 
 
 U 2 bling 
 
148 Metallic Bodies, 
 
 Arsenic, blinga baking oven; whole flew is an horizontal pipe, near an hundred fa- 
 w — v~— thorns in length, of confiderable width at the end where it communicates with 
 the furnace, and growing gradually narrower to the other end. The ore is 
 every now and then ftirred and turned in the furnace, to promote the extrica- 
 tion of the Arfenic; which arifes in-fumes into the pipe, and there condenfes 
 into a grey i fa or blackifh powder called Meal Arfenic. The meal Arfenic is 
 refined by a fecond fubiimation in clofe vefifels, with the addition of a little Pot- 
 afh, which detains its impurities : In this operation, the fire which elevates 
 the Arfenic heating the receiver, the flowers melt together into the cryftalline 
 mafTes brought to us. The whiteft and purefi: Arfenic, fublimed with a little 
 Oil, from Iron filings, or from any inflammable matter, becomes grey or 
 blackifh like the crude meal ; and becomes white again by a refublimation 
 from Pot-afh. Henckel obferves, that Quickfilver alfo detains this inflam- 
 mable or colouring matter, and does it moje effectually than any other fub- 
 ftance The ores, particularly the black fort, fublimed in clofe veflels, with- 
 
 out addition, yield alight, porous, foliaceous, Regulus of Arfenic. 
 
 Arfenic in The red Silver-ores, feveral of the Copper-ores, and moft of the ores of 
 ores. Tin, abound with Arfenic; which evaporating during the fufion of the ore, 
 
 in part condenfes about the top of the furnace, and forms lublimatesof various 
 colours, white, grey, yellowifh, &c. according to the admixture of Sulphur or 
 other matters. The Arfenic carries off in its exhalation fome portion of the 
 metal : At Andreafberg, the arfenical vapours which arife in the working of 
 Silver-ores, are caught in a proper refervoir, and fome Silver recovered from 
 the Sublimate. 
 
 C ob a lt. 
 
 There is a Angular ore of Arfenic called Cobalt, Cobaltum pro caruleo , Cadrnia 
 metallic a , Blaufarben kobold. This appears of a whitifh colour, fomewhat darker 
 than the white Arfenic ores ffriCtly fo called, and differs from them remarkably 
 in fome of its properties * yielding, after the diflipation of its Arfenic, the blue 
 Glafs called Smalt, and the fublfance commonly ufed for tinging Glafs blue 
 under the name of Zaffire, Zafficra , Zaffioer , &c. This ore is moll plentiful in 
 Saxony, particularly near Schneeberg in the diftriCt of Mifnia. It is found 
 alfo in feveral other parts of Europe : At St. Andreafberg in the Upper Hartz, 
 large quantities have been met with for upwards of twenty years ; but the ma- 
 nufacture of ZaffVe and Smalt is confined to Saxony alone, no method having 
 been found ellcwhere of making the colour fucceed. Saxony has long fupplied. 
 all the other parts of the world with thefe commodities, and exports them even 
 to the Eaft-Indies. The general method of preparing them is delcribed by 
 Kunckel ; but there are fome particular managements in the operation, which 
 the workmen are bound by an oath hot to reveal ; and a prohibition is laid cn 
 the exportation of unmanufactured Cobalt (k). 
 
 The 
 
 [k] Cobalt.} This mineral, in its purer 
 hates, is confiderably compact and heavy, 
 and not unfrequently of a femimetallic ap- 
 pearance. Its texture is always fine; fome- 
 times granulated, or compofed of minute 
 
 grains ranged into fmall Itriae ; fometimes 
 fmooth and even, without any diftinguifli- 
 able grain. Its colour is fometimes a pale 
 iron grey, fometimes a darker bluifh or 
 blackifh grey. From variations in the ap- 
 pearance 
 
Metallic Bodies. 149 
 
 The ore is firfi: reduced into powder in ftamping-miiis ; then calcined, andCo balt. 
 the Arfenic colledled, in the manner above defcribed. The remaining mineral — v — — J 
 is pulverized and calcined afrefla, and this repeated perha s a third time, that 
 the Arfenic may be completely expelled. After the iaft calcination, it is 
 pafied through a fine fieve, which is moved by a mili : What will not pafs, is 
 ground and calcined again. The powder thus prepared is fit lor making either 
 Zaffire or Smalt. 
 
 For 
 
 pearanee of the mineral itfelf, or from its 
 different admixtures, fome of the mineralo- 
 giffs have divided it into diftinct fpecies, the 
 principal of which are thefe. (i.) Dark 
 grey Cobalt ; compact, ponderous, and of a 
 very fine grain. This fort is faid to be the 
 moft efteemed at the Saxon works, and to 
 afford the fineft blue glafs. (2.) Bright 
 pale grey or afh-coloured Cobalt ; of a 
 fomewhat loofer ftru&ure, and lefs ponder- 
 ous. This kind has a great refemblance to 
 the arfenical Pyritae, and fome of the white 
 Silver and Copper ores ; from which, thofe 
 who are accuffoined to the infpeCtion of 
 thefe minerals diftinguilh it, pretty readily, 
 by the colour of the Cobalt being fomewhat 
 duller, and its texture finer. (3.) Vitreous 
 Cobalt ; in ftrufture refembling melted fco- 
 ria or glafs, of a bright bluifh grey colour ; 
 called by the Germans Scblackenkobold , flag 
 Cobalt. (4.) Cryftalliform Cobalt; affect- 
 ing chiefly a cubical figure, fometimes per- 
 fect, but commonly with the angles im- 
 perfect. (5.) Specular Cobalt; inter- 
 mixed with glittering talky flakes. (6.) 
 Earthy Cobalt; blended with various earths 
 into foft friable compounds, of a black, yel- 
 lowifh, grey, or other colours. (7.) Flowers 
 of Cobalt. Thefe are of a Joofe radiated 
 ftruCture, and generally not fo heavy as the 
 foregoing ores. The external parts are of 
 a fine purplifh red, a violet, or a peach 
 bloom colour : Sometimes the whole mafs 
 is elegantly tinged with thefe colours 
 throughout, but more commonly the inter- 
 nal parts are of a greyifti or leaden hue. 
 They are never found in great quantities, or 
 forming regular veins ; but only in detached 
 mafles, lodged in clefts of Hones, in places 
 to which the air has had free accefs. They 
 appear to proceed from a fpontaneous refo- 
 lution of fome of the foregoing minerals ; 
 molt of which are found upon experiment 
 to yield nearly fimilar efflorefcences on be- 
 
 ing expofed in heaps for a length of time 
 to a moift air. Wherever the workmen 
 meet with thefe flowers, they expeCt a rich 
 vein of Cobalt in the neighbourhood. 
 
 The Cobalt mines of Schneeberg are faid 
 to be two or three hundred fathoms deep ; 
 and the Cobalt lodged at great depths to be 
 of a better quality than that which is near 
 the furface. The Schneeberg hill, accord- 
 ing to the ancient chronicles of Saxony, 
 yielded at firft only an Iron ore ; which on 
 finking deeper, about the beginning of the 
 fourteenth century, was fucceeded by a very 
 rich ore of Silver: This alfo, being at 
 length exhaufted, gave place to Cobalts. 
 Some pieces of the Cobalt ores are ftiil 
 found to participate of Silver, and even of 
 Gold : Schluter relates, that he has fome- 
 times obtained after the proportion of three 
 ounces of Gold and upwards upon the hun- 
 dred pounds. Thefe metals however, far 
 from being eflential, as fome have raihly 
 fuppofed, to all Cobalts, are entirely acci- 
 dental even to this : Nor are they equally 
 diffufed through thole mafles in which they 
 happen to be iodged ; different pieces con- 
 taining different proportions, and fome none 
 at all. 
 
 Cobalt has been met with in fome paits 
 of England ; at Mendip hills in Somerfet- 
 fhire, and in Cornwall ; in which laft 
 county it has of late been dug in confider- 
 able quantity, though not entirely agreeing 
 in quality to the accounts given by authors 
 of the forts which are manufactured in 
 Saxony- It is fuppofed that the Chinefe, 
 and more particularly the Japonefe, had 
 formerly mines of an excellent Cobalt, with 
 which were painted the fine blues of their 
 ancient porcelanes ; but that thefe mines 
 are now exhaufted, and that the inferior 
 blues of their prefent ware are painted with 
 the Saxon Zaffre imported to them by the 
 Dutch. 
 
150 
 
 Metallic Bodies. 
 
 C O B A LT. 
 
 ZafFre. 
 
 Smalt, 
 
 For ZafFre, a quantity of Flints, or of the flinty {tones found adhering to 
 ores and called by the miners quartz , is reduced into a fine powder, and 
 Lifted. One part of the calcined Cobalt is mixed with two, three or more parts 
 of the powdered Flint, according as the ZafFre is intended to be of the beft or 
 of an inferior kind. This mixture is moiflened with water, and prefled clofe 
 into wooden cafks for exportation. On (landing, it acquires by degrees a 
 flony hardnefs ; though if no water is added, it continues powdery or crumbly. 
 It is ufed for tinging Glafs of various fhades of blue •, and for the blue glazing 
 of earthen ware. 1 have known Lapis lazuli imitated with it. 
 
 Smalt is made by mixing the calcined Cobalt with a certain proportion of 
 fand and Pot-afli, the common ingredients of Glafs, and vitrifying the mix- 
 ture with a ftrong fire : After the fufion, a metallic matter, called Regulus 
 of Cobalt, is commonly found at the bottom : This is employed in fubfequent 
 vitrifications. The whiter the fand, and the purer the Pot-afh, the finer will 
 be the colour of the Glafs ; and the fmaller the proportion of thefe ingredients, 
 the deeper the colour: Lienee the different fortments of Smalt, common, good, 
 fine, and fuperfine. The Glafs of each kind is ftamped in mills, ground be- 
 twixt two hard (tones, walked, further forted, dried and packed up(/). 
 
 White 
 
 (/) Taffre and Smalt. ] The preparation of 
 thefe concretes was long kept an entire f'e- 
 cret, and their origin in general unknown. 
 Many have fuppofed ZafFre to be a native 
 earth or (tone ; and even the learned Dr. 
 Merret, after rejecting this opinion, endea- 
 vours to eftablifn a no lefs erroneous one, 
 that it is a compound of Brafs, Calamine 
 and Sand. Libavius however, fo early as 
 the year 1506, gave fome account of its 
 true production : He fays that, after the eli- 
 quation of Bifmuth from its ore, recrementa 
 m lignis iff fovea fubfiflunt .... qua .... re- 
 verberii fur no exercitata , in lazurium figulorum 
 vitrarior unique iff fimilium tranfinutantur , titulo 
 zaphara. Kunckel was the fil'd who gave 
 any circumdantial detail of the method of 
 preparing thefe fubftances ; and to his ac- 
 count fome later writers have added further 
 particulars. As attempts are making to in- 
 troduce this manufacture into England, it 
 may be proper to colleCt into one view all 
 the information we can procure from them 
 in regard to the management of the procefs 
 in Saxony. 
 
 The Cobalt, taken out of the mine, is 
 broken with hammers, into pieces about the 
 lize of a hen’s egg ; and the ftony involu- 
 crum, with fuch other heterogeneous mat- 
 ters as are diftinguifhable by the eye, as 
 much as poffrble feparated. In this date, 
 it is allayed, valued, taxed, tithed, and de- 
 
 livered to the manufactures In digging 
 
 the mines, the workmen frequently meet 
 with hard fandy maffes cutting and inter- 
 rupting the vein. Thefe are broken in 
 mills ; and the Cobalt, that had been im- 
 bedded in them, feparated by fieves. 
 
 The mineral, brought to the manufac- 
 tures, is pounded in damping-mills, and 
 fifted through brafs-wire fieves : According 
 to fome, the lighter earthy parts are wafhed 
 off by water. It is then calcined, in a 
 large fiat-bottomed, arched furnace, refem- 
 bling a baking oven, in which the flame of 
 the wood reverberates upon the ore. The 
 mineral is occafionally dirred or turned dur- 
 ing the calcination, with long handled iron- 
 hooks or rakes ; and the procefs continued 
 till it ceafes to emit any fume : An hundred 
 pounds are faid to lofe twenty or thirty. 
 
 Some relate, that the calcination is re- 
 peated feveral times, the ore being taken 
 out and ground into powder each time 5 
 others, that it is calcined but once, and the 
 calcination continued from four to nine 
 hours, according to the quality of the Co- 
 balt. Some of the affayers lay great drefs 
 on the degree of calcination ; and report 
 that on this circumdance, not only the 
 beauty of the colour, but the quantity of 
 coloured glafs obtainable, in great meafure 
 depend ; and that the degree of calcination 
 which fome Cobalts require, would be in- 
 jurious 
 
Metallic Bodies. 
 
 151 
 
 jurious to others. Some, however, feem 
 to be of opinion, that Cobalts may be 
 allayed with fufSicient accuracy, both in re- 
 gard to colour and quantity, without any 
 calcination at all, by barely melting the ore 
 
 with Borax- The Cobalt taken out of 
 
 the calcining furnace is palled through 
 very clofe brafs-wire fieves ; and fuch part 
 as has concreted into lumps, pounded and 
 lifted afrelh, till the whole is reduced into 
 fine powder. 
 
 During the preparation of the Cobalt, 
 fome Flints are calcined in another fur- 
 nace, and thrown red-hot into water ; by 
 which they are rendered friable and eafily 
 pulverable. The pureft and whiteft ftones 
 are made choice of ; or fuch at leaft as be- 
 come white by calcination. In want of 
 thefe, white fand is ufed. 
 
 Zaffre is compofed of one part ef the cal- 
 cined Cobalt, and one or two of the cal- 
 cined Flint, mixed together by lhaking in a 
 wooden box and fifting, and then moiltened 
 with water. Macquer and fome others re- 
 port, that a certain quantity of Potafh is 
 added to the above mixture, and the whole 
 imperfectly melted. This account has little 
 probability ; as the ftony powder is very 
 diftinguifhable in Zaffre, without any ap- 
 pearance of its having been united with the 
 Cobalt by fufion ; and as the maffes have 
 the fhape of the wooden tubs in which they 
 are brought to us, and confequently cannot 
 owe their hardnefs to fire. 
 
 For making the blue Glafs, called in the 
 mafs Smalt , and when powdered Smalts or 
 powder blue ; one part of the calcined ore is 
 mixed with one, two or more of the Flint, 
 and one or more of Potafh ; and the mix- 
 ture melted in large crucibles, in a furnace 
 much refembling that of the glafs-houfe. 
 In each furnace are generally fix crucibles, 
 placed about the middle of its height. 
 
 The furnace has two doors, one in the 
 front, the other behind : Through the lat- 
 
 ter common billets are put in ; through the 
 former, fplit wood, dried almoft to Char- 
 coal in an adjoining oven heated by the 
 furnace. In the front door is an aperture, 
 for introducing final! effays, which is occa- 
 fionally clofed with a piece of loam. In 
 each fide are three apertures for conveying 
 the matter into the crucibles, and, after 
 fufion, taking it out with Iron ladles : A- 
 bove thefe are three others, which are 
 
 opened occafionally for introducing the C O B A LT. 
 tongs to move or fettle the crucibles : At < — ,„ ■» 
 
 the bottom are two more apertures, for tak- 
 ing out the allies and fuch part of the Glafs 
 as may have rup out and fallen down a- 
 mong them ; this is melted over again. 
 
 After the fire has been continued for fix 
 hours, the matter is ftirred every quarter of 
 an hour, with iron rods, to make the mix- 
 ture the more equal : The fire is kept up in 
 all, for the heft Smalt twelve hours, for the 
 inferior kinds ten or eight. The mark of 
 fufficient vitrification is, the Glafs which 
 adheres to the Iron ftirrer drawing out into 
 a fine thread. The whole is now taken 
 out with -ladles, and poured into a tub of 
 cold water, to render it more eafily pul- 
 verable. 
 
 At the bottom of the crucibles is found a 
 metalline Regulus, of a whitifh colour, in- 
 clining to red, and extremely brittle. When 
 the crucibles have become unfit for any fur- 
 ther fufions of the Glafs, thefe Reguli are 
 melted in them, and are thus refolved into 
 two diftindt metallic bodies, one which falls, 
 to the bottom, and another which floats 
 above. The firft is faid to be Bifmut’n : 
 
 The latter is a femimetal of a different 
 kind, which yields a blue Glafs, and ac- 
 cordingly is pulverized and added in frefh 
 mixtures. 
 
 The Glafs appears in the mafs of an'opake 
 deep blue, almoft black 1 when reduced in- 
 to moderately fine powder, of a pleafant 
 light blue : The further it is comminuted, 
 the paler. It is firft beat in a ftamping- 
 mill, and paffed- through a brafs-wire fieve, 
 an iron one being apt to ruft and fpoil 
 the colour ; after which, it is ground with 
 water, on a fmooth hard ftone placed at the 
 bottom of a large vat or tub, by two other 
 hard ftones turning vertically: The water, 
 loaded with the fine powder, is let off by 
 cocks into other veffels, and fuffered to. 
 fettle : After the coloured pow’der has fub- 
 fided, a white one remains fufpended in the 
 water, which is now poured off, that the 
 white matter may fettle by it-felf : This is 
 employed in frefh mixtures, in the room of 
 Flint and Potafh. The coloured powder is 
 wafhed again, dried in a ftove, paffed; 
 through fine fieves, and divided into diffe- 
 rent fortments, according to the finenefs of 
 the powder and the beauty of the colour. 
 
 In the laft place, it is moiftened with a 
 
 little: 
 
152 
 
 Meta i. Lie Bodies. 
 
 C o b a lt. little water, and packed up in cafks for ex- 
 - v — > portation. 
 
 The richnefs of Cobalt is judged from the 
 quantity of Flint and Potafh with which it 
 will form a fufficiently deep powder blue. 
 The manufadtures are provided with affay- 
 ers, for determining the quantities which 
 different parcels of the ore will bear. The 
 produce of Smalt appears to be never lefs 
 than equal, nor more than four times the 
 weight of the crude ore. 
 
 and then melted with ^different vitreous 
 compofitions, yielded a large portion of 
 Regulus, theGlafs acquiring only a brownilh 
 or blackifh colour probably from ferrugine- 
 ous or other heterogeneous admixtures : On 
 ftrongly calcining the mineral, by long con- 
 tinued fire or by Nitre, the Glafs turned 
 out blue, and little or no metallic matter 
 feparated. 
 
 REGULUS of COBALT. 
 
 Chemical hiftory of Cobalt.'] The colouring 
 matter of Cobalt appears, not, as has been 
 generally fuppofed, to be an earth, but a 
 femimetal, of a peculiar kind, effentially 
 diftindt from all the others ; revivable, in 
 its proper metallic form, either from the 
 blue Glafs or the calcined Cobalt, by fufion 
 with the common inflammable fluxes. To 
 Dr. Brandt, of the Swedilh Academy, we 
 owe the firft knowledge of this fubftance as 
 being a femimetal Jui generis : It is called 
 Regulus of Cobalt. 
 
 Cobalt may be looked upon as the ore of 
 this femimetal : Its other contents are as 
 various and inconftant as thofe of any other 
 ores. Almoft all Cobalts contain a large 
 admixture of Arfenic, fome of Iron, and 
 others ofBifmuth: The greater number 
 
 participate alfo of another new femimetal, 
 firft difeovered by Mr. Cronftedt in the year 
 1751, and called, from the name of the mi- 
 neral which yields it moft plentifully, Nickel. 
 The two metallic Reguli, which feparate in 
 making the Glafs, appear to be Bifmuth, 
 and a part of the tinging Regulus of the 
 Cobalt ; for it is a property of thefe two 
 femimetals not to mingle in fufion with one 
 another. 
 
 The blue Glafs depends on the vitrifica- 
 tion of the colouring femimetal ; and me- 
 tallic fubftances in general cannot be vitri- 
 fied, or combined with vitreous matters, till 
 they are deprived of their metallic form, 
 and changed into calces. Moft metals are 
 naturally, in their ores, in the ftate of calx: 
 The Regulus of Cobalt is often naturally 
 metallic, and fubfides in its proper form 
 upon bringing the ore into fufion, without 
 any of the inflammable additions, which 
 moft other ores require for the revival of 
 their metal. Several fpecimens of Englifh 
 Cobalt, moderately roafted till greateft part 
 of the Arfenic was judged to be diffipated, 
 1 
 
 "D Egulus of Cobalt is a brittle femimetal, 
 fufible in a moderate red heat, nearly 
 the fame with that in which Silver melts. 
 On continuing the fire, it changes flowly 
 into a blackifh calx ; which urged with a 
 very violent fire, runs at length into a bluifh 
 black Glafs. By the addition of different 
 proportions of vitreous matters that have 
 no colour, all the different fhades may 
 be obtained, from the deepeft to thelighteft 
 blue. The glaffes that are moft loaded 
 with colour, if held in the flame of a candle, 
 crackle, fwell, and become white. 
 
 It does not amalgamate with Mercury, 
 nor mingle in fufion with Bifmuth : With 
 this laft it is rendered mifcible by the media- 
 tion of Nickel or of Regulus of Antimony: 
 With all the other metals, it mingles readily. 
 It whitens Copper, and renders it brittle, 
 but feems remarkably to improve the mal- 
 leability of Iron : Brandt relates, that the 
 metal obtained in fufion from a ferrugineous 
 Cobalt-ore, and which was found to be 
 compofed of Iron with a confiderable pro- 
 portion of this Regulus, proved as malle- 
 able as the beft forged Iron : This com- 
 pound, calcined and vitrified, yielded a 
 good Smalt; the black Glafs, which Iron 
 affords, feeming to be of little injury to the 
 blue of the Cobalt. 
 
 Regulus of Cobalt, both in its metallic 
 form and in that of a calx, diffolves readily 
 in Aqua fortis into a red liquor. As few 
 metallic bodies befides are adfed upon by 
 that acid when fully calcined, and as thofe 
 that are do not influence the colour; we 
 are hence furnifhed with means of difeover- 
 ing this Regulus in ores after ftrong calcina- 
 tion, whatever other metal they may contain. 
 
 Solutions of the femimetal, or tindfures 
 of the calcined ore, made in the pure ni- 
 trous acid, fuffer no change of colour from 
 heat. It Sea-lalt or its acid is added, they 
 
 affume 
 
Metallic BoDtEs. 1 5 3 
 
 White Arfenic, fublimed with one tenth its weight of Sulphur, forms a yel- Arsenic. 
 low compound, which melts together, if the receiver is heated, into femitran* 
 fparent cryftalline maffes, called yellow Arfenic. If the quantity of Sulphur is T V r anti 
 
 doubled. 
 
 aflume a deep emerald green when mode- 
 rately warmed, and on cooling become red 
 again as at firft : Duly infpiflated, they 
 yield rofe-coloured cryftals, which change 
 their colour in the fame manner. See p. 1 14. 
 
 Pure Spirit ofSalt diflolves this femirnetal 
 into a reddifh yellow liquor, which inftantly 
 becomes green from a very gentle warmth. 
 On faturating the folution with urinous fpi- 
 rits, the Precipitate appears at firft white, 
 but afterwards becomes blue, and at length 
 yellow. 
 
 The vitriolic acid diflolves this femirnetal 
 more flowly than the two foregoing. The 
 folution is of a role-colour, and fuffers no 
 change from heat ; but in evaporation, it 
 throws off to the fides of the glafs a blue 
 powder, which on cooling grows white. 
 Fixt alcalies precipitate from this folution a 
 white powder, volatile fpirits a greyifh one ; 
 On adding more of the fpirit, the Precipi- 
 tate is taken up again, and the liquor ap- 
 pears of a beautiful red. 
 
 This femirnetal is precipitated from acids 
 by Zinc, not by Iron. 
 
 NICKEL. 
 
 “KJ Ickel is a white femirnetal, when com- 
 pared with Silver inclining a little to 
 reddifh, of a clofe texture, and very bright. 
 Its fpecific gravity is to that of water nearly 
 as 8f to 1. 
 
 It melts in a ftrong red or li°;ht white 
 
 O o O 
 
 heat ; and on continuing the fire rifes up 
 Into little efflorefcences, which change at 
 length into a deep green calx. By a longer 
 continuance of an intenfe fire, the calx be- 
 comes brown, but does not vitrify, nor is it 
 difpofed to vitrification by the addition of 
 Glafs. Neverthelefs Borax, fufed with the 
 femirnetal itfelf, acquires a confiderable 
 reddifh brown tinge : This vitreous matter, 
 further urged, becomes violet, and at laft 
 colourlefs, like glaffes tinged with Manga- 
 nefe. Mixtures of Nickel, Regulus of 
 Cobalt and Iron, being flightly calcined and 
 fufed with Borax, the Iron feparates firft in 
 form of a black Glafs - 3 on repetitions of the 
 
 procefs, the Regulus of Cobalt vitrifies, 
 blue ; leaving behind the pure Nickel, more 
 difficultly vitrefcible than any other of the 
 imperfedt metals. 
 
 Nickel makes no confiderable detona- 
 tion with Nitre; and is very flowly cor- 
 roded by it into a yellowifli green fufible 
 fcoria. With Sulphur' it has a great affi- 
 nity, abforbing it from moft, if not all the 
 other metallic bodies, and detaining it in a 
 very ftrong fire ; even the calces, thoroughly 
 burnt, perfectly unite with it. The fulphu- 
 rated Nickel is externally of a bright metal- 
 lic appearance, internally yellow, very 
 hard, and compact as Steel : It eafily cal- 
 cines ; and, before a bellows, throws out 
 red fparkles with confiderable noife. 
 
 It refufes any degree of union with Sil- 
 ver, Quickfilver and Zinc ; but mingles 
 readily with all the other metals, and proves 
 a medium for uniting two repugnant ones, 
 Bifmuth and Regulus of Cobalt. It ren- 
 ders the malleable metals hard and brittle, 
 whitens Gold and Copper, and difpofes the 
 latter to tarnifh quickly in the air. 
 
 It diflolves with eafe in the nitrous and 
 marine acids into a deep green liquor : 
 Hence the green tindture which fome forts 
 of Cobalt communicate to thefe menftrua, 
 and which has generally been attributed to 
 Copper. It is not adled on by the vitriolic 
 acid, whether concentrated or diluted. It 
 is not precipitated from acids by any metal $ 
 and but flowly by alcaline Salts, into a 
 greenifh white powder*. Volatile alcalies } 
 added in larger quantity than is fufficient to 
 precipitate it, take it up again, the liquor 
 appearing blue. 
 
 This femirnetal, from its great affinity' 
 V/ith acids and with Sulphur, and its entire 
 repugnancy to Stiver, promifes to be art 
 ufeful addition for the reduction of Luna 
 cornea and fulphurated Silver. Mr. Cron- 
 ftedt, (from whom thefe obfervations are 
 extracted) made feveral trials of this kind, 
 and conftantly found the Silver of perfect 
 purity, lying diftinift from the Nickel, See 
 the Svenflia vetenjkapi acad&tnlin$ handllngi f .t\ 
 an 1751 f 1754. 
 
 X 
 
r 54 
 
 Metallic Bodies. 
 
 Arsenic, doubled, the compound proves more opake, and of a fine red colour, and hence 
 
 is called red Arfenic. This is of a lefs beautiful red than the combination of 
 Sulphur with Mercury, that is, Cinnabar ; and has its colour debafed, whilft 
 that of Cinnabar is improved, by grinding into fine powder. If the quantity 
 of Sulphur is a little increafed above the proportion which affords the yellow 
 Arfenic, an orange coloured Sublimate is obtained. The more the Sulphur is 
 increafed, to a certain point, the Sublimate proves the redder, and more vo- 
 latile. When equal parts of each are ufed, the dark red colour is diluted into 
 an aurora, and the mixt concretes into a beautiful tranfparent mafs, called ruby 
 of Sulphur or of Arfenic, or golden Sulphur. 
 
 The workmen, in making the red and yellow Arfenics, take, inffead of 
 white cryftalline Arfenic, the rough meal as it firft fublimes from the ere. 
 Sometimes they mix the meal Arfenic with fulphureous ores inffead of Sulphur 
 itfelf, or Sulphur with the arfenical ores-, and fometimes they extradt yel- 
 low or red Arfenics by one fingle fublimation from minerals in which Arfenic 
 and Sulphur are naturally contained. Henckel relates, that the preparation of 
 red and yellow Arfenic, with pure white cryftalline Arfenic and pure Sulphur, 
 does not fucceed, or not without great difficulty. But if pure white cryftalline 
 Arfenic be mixed with one tenth its weight of pure Sulphur, they may beeafily 
 melted together, in a glafs body, into a femitranfparent, orange-coloured or 
 reddifh mafs, which fublimes into a femitranfparent, citron yellow, hard, 
 brittle, fubl innate ; a minute portion of more fixed matter remaining at'the 
 bottom. The proportions of Arfenic and Sulphur in thefe kinds of compoft- 
 tions, maybe judged from their fpecific gravity-, the gravity of Arfenic being 
 to that of Gold as i to 5, whilft the gravity of Sulphur is to Gold only as 1 to 
 9: Hence the more Sulphur they contain, the lighter; and the more Arfenic, 
 the heavier they will be. The poifonous quality, which the Arfenic poffeffes 
 by itfelf, is, in thefe, confiderably abated by the Sulphur. They are never- 
 thelefs far from being innocent: Thofe who are employed in grinding them 
 for the ufe of painters, are apt to become paralytic. 
 
 Natural mixtures of Arfenic and Sulphur, called Aurifigmenta or Orpiments, 
 realgar, rifigal, fandaracha, are not unfrequently met with in the earth, particu- 
 larly in the e after n countries. Mr. Pott has given an excellent differtation on 
 Orpiment, from which it may be proper to make a ftiort extract. 
 
 Orpimsntv “ Auripigmentum, fo called from its being uled as a gold-coloured Pig- 
 
 X „ (T* 1 .. T 7 a: ry ; h „ ry ■ ■ / 
 
 — — * J * - J- ^ ~ ^ vxaw a ~ J 1 t ai-i.viuv, 
 
 to be poffeffed of a poifonous quality -, but it is neither one, nor the other. 
 This error feems to have proceeded from Agricola 5 .s relation, copied by many 
 later writers, that white Arfenic is prepared from Orpiment and common Salt 
 fublimed together. Hoffman made trial of fuch a compofition,. but obtained 
 from it no white Arfenic. 
 
 Orpiment is a native foffil, found chiefly in Turkey and Natolia, Some 
 is met with alio in Bohemia, Hungary, and Lufatia near Sorau, but inferior in 
 goodaefs to that of Turkey. The belt fort is of a lively gold-yellow and green 
 
 a 
 
 colour, 
 
 u 3 
 
Metallic Bodies, j ^ 
 
 colour, here and there intermixed with pieces of a vermilion red of a lhattery Orpiment. 
 foliaceous texture, fomewhat flexible, fort to the touch like Talc, and fpark- 
 ling when broke. The inferior kinds are of a dead yellow, inclining more to 
 greenifh ; and want the fparkling appearance of the foregoing. 
 
 It burns in the fire, but not very eafily, with a deep blue, or a dark bluifh Examined by 
 white flame and a fulphureous fmell; and at the fame time melts and becomes fire * 
 red. If the fire is continued, it arifes in white or rather yellowifh white fumes, 
 which condeni’e partly into reddifh and partly into white flowers-, an earthy, 
 fandy, or ftony matter remaining behind. Hoffman obferves, that the fume 
 of Orpiment flains a knife of a yellowifh white and reddifh colour and fays 
 that the red Arfenic of the ancients was no other than Orpiment melted into 
 a cinnabarine red mafs. Cramer relates, that as foon as it burns it. melts, and 
 being then poured out upon a clean Marble or Iron plate, forms on cooling a 
 deep red, femitranfparent, compadt, brittle fubftance-, leaving a porous fpark- 
 ling matter, refembling an imperfedl fcoria, lefs fufible than the Orpiment at 
 firlt, and which in a ftrong fire falls into a grey earth. 
 
 Orpiment confifts of Sulphur and Arfenic. Some affirm that it has a corro- Depilatory, 
 five quality, fo as to make the hair fall off, and hence fuppofe it to confifl of acri- 
 monious Salts. But Orpiment of itfelf has no fuch power: It is a mixture of 
 it with Quick-lime which has that effedt, and Quick-lime will produce the 
 fame effedt without it. A Lixivium made by boiling Orpiment in Lime- Sympathetic 
 water, gives colour to invifible writings with the fympathetic Ink. The fym- Ink * 
 pathetic Ink is a folution of Litharge in Vinegar, or of Sugar of Lead. This 
 folution, written with on paper, leaves no ftain, any more than pure water : 
 
 But if a piece of bibulous paper, dipt in the folution of Orpiment and tho- 
 roughly dried, be laid upon the writing, the characters will prefently become 
 black and legible. The fame bibulous paper impregnated with the Orpiment, 
 will anfwer repeatedly for a length of time : It will likewife produce its effedt, 
 though more flowly, without the immediate contadt of the writing, and even 
 with a thick book interpofed betwixt them. A like black colour refults upon Method of 
 mixing the folutions of Orpiment and of Lead together ; and hence we are fur- difcovering 
 nifhed with means for difcovering the dangerous fraud of impregnating wines Lead in -O* 
 with Litharge : If the Wine, on being mixed with the folution of Auripig- cl ' JOrs ' 
 ment, acquires a brownifh red or a blackifh colour, we may be fure it has fuf- 
 fered that abufe. The produdfion of the colour in thefe experiments, proceeds 
 from the fulphureous part of the Orpiment tinging or tarnifhing the particles 
 of Lead. 
 
 That Orpiment contains Sulphur, appears from hence-, that one part ofQjmpcfed of 
 Orpiment with half a part of Nitre and Salt of Tartar, mixed together and Sulphur and 
 .expofed to the fire, flafh and explode with great vehemence ; a phenomenon Arfenic. 
 never obferved from Nitre and Salt of Tartar without Sulphur. Agricoia 
 furely never tried the procefs which he diredls in his notes on Poppius, of fub- 
 liming this fulminating compofition in a glafs body for the fpace'of ten hours : 
 
 If fuch a procefs was attempted, the vefiels would foon be buril in pieces, to 
 the hazard of the operator’s life. A mixture of Orpiment and Nitre, inje&ed 
 Into a red-hot crucible, deflagrates with a bright flame, in the fame manner as a 
 mixture of Sulphur and Nitre: Some white arfenical flowers arife, and the re- 
 
 X 2 mainder 
 
ic5 Metallic Bodies. 
 
 -J 1 
 
 Orpiment. mainder is a fixed Arfenic. It were needlefs to bring more evidences ofOrpi- 
 
 — ’ ment containing Sulphur, when the fine Cinnabar parable from Orpiment and 
 
 Mercury-fublimate is ofitfelf an inconteftable proof. 
 
 That this mineral contains Arfenic, appears from the arfenical flowers which 
 it yields in the fire, and the fixt Arfenic which remains upon deflagrating it 
 with Nitre : This refiduum whitens Copper in the fame manner as common 
 fixt Arfenic. Arfenic melted with alcaline Salt and Sope or other fat matters, 
 Reo-ulus of yields a fparkling Regulus ; and Orpiment, treated in the fame manner, affords 
 Arfenic. a Regulus agreeing in all refpedts with the other. The Alcali abforbing the 
 Sulphur of the Orpiment, forms with it a hepar Sulphuris ; which diflblves in 
 water, and on the addition of Vinegar depofites a fulphureous Precipitate, in 
 the fame manner as the antimonial fcoria. The following experiment puts this 
 affair beyond difpute. If equal parts of Orpiment and Sope be well mixed 
 together, the mixture put into a glafs retort, and the fire gradually raifed ; 
 at firft, a whitifh, undtuous, fulphureous liquor arifes ; next a portion of the 
 Sulphur of the Orpiment fublimes into the neck of the retort, partly tinged 
 blackifh by tfie Oil of the Sope, and partly appearing yellow and reddifh ; at 
 laft, in a red heat, a fparkling Regulus, the fame with Regulus of Arfenic, 
 fublimes : A fmall . portion of the Sulphur of the Orpiment remains behind, de- 
 tained by the Alcali of the Sope. The fulphureous Sublimate participates of 
 the arfenical matter of the Orpiment, and hence difeovers a poifonous quality, 
 though in a far lefs degree than the Regulus, or the white flowers of Orpi- 
 ment. 
 
 P octofts Half a pound of Orpiment, and a pound of Mercury' fublimate, were well 
 from Orpi- mixed together, put into a wide-necked glafs retort, and fuffered to Hand for 
 ment, with a day and night in a cellar; a large receiver being then adapted and clofely 
 Sublimate. ] utec j 9 a gentle fire applied and increafedby degrees; there arifes a confiderable 
 quantity of a fmoking fpirit, clear and tranfparent as water, called butter of 
 Arfenic or of Orpiment : This is followed by an oily liquor, which like vege- 
 table oils, fwims upon the fpirit, and if an hundred times forced under it, ftill 
 rifes to the furface again : On further increafing the fire, a confiderable pro- 
 portion of Cinnabar fublimes ; and there remains, in the bottom of the retort, 
 a little yellow, light, crumbly matter, which is the earth of the Orpiment. 
 There arofe alfo a little arfenicated Sulphur, not faturated with the Mercury, 
 of a red colour, refembling a ruby. Some diredt, for this procefs, equal parts of 
 the Orpiment and Mercury-fublimate ; but unlefs the Sublimate is taken in a 
 larger quantity, its acid will be infufficient to diflolve and elevate the Arfenic, 
 and its Mercury infufficient to form a true Cinnabar with the Sulphur. The 
 fame thing happens in this operation, as in making the butter of Antimony: 
 The marine acid of the Sublimate quits the Mercury, to unite with the arfenical 
 Regulus with which it has. a greater affinity ; whilft the Mercury of the Subli- 
 mate unites with the Sulphur of the Orpiment, The greater fluidity of the but- 
 ter of Orpiment than of the butter of Antimony depends on the different quali- 
 ties of their metallic part; the Regulus of Orpiment being more fubtile, fu- 
 fible, volatile, of greater adlivity upon metallic bodies, than the Regulus of 
 Antimony. The butter of Orpiment, dropt into water, depofites a white 
 powder in the fame manner as butter of Antimony does : This powder, edulco- 
 rated^ 
 
Metallic Bodies. 157- 
 
 rated, and fet to fublime in a Silver box clofely luted, corrodes the Silver, fo as Orpiment* 
 to render it in part fpongy like a Pumice. Cobalt, Bifmuth-ore, and the red ~v— 
 Silver-ore, which are all arfenical, have the fame effed: upon Silver. If the 
 butter or Spirit of Orpiment be mixed with Spirit of Nitre, and fet to diftil, the 
 phenomena are the fame as when butter of Antimony is treated with that acid : 
 
 A powder which is no other than fixed Arfenic, remains ; and an Aqua regia 
 arifes, impregnated with a part of the Arfenic, fo as to render Gold white;, 
 whence fome have been induced to believe, that the tinging matter of Gold 
 was extraded by this menftruum. 
 
 With regard to the oil it has been fuppoled by fome not to proceed from the 
 Orpiment, and to be no other than a folution of a part of the Mercury- Cubli — 
 mate : But the fame kind of liquor is obtainable, without the addition of any 
 Mercury-fublimate, from Orpiment and common Salt, with a fuitable quan- 
 tity of Oil of Vitriol to extricate the acid of the Salt : Arfenic treated in the- 
 fame manner yields no fuch oil. This oil, dropt into water, renders the liquor 
 turbid. On the addition of Oil of Vitriol, it coagulates, and a kind of fiimy 
 matter fubfides : If water be now poured in, a white oil appears at the bottom, 
 which on Handing difiblves into a clear liquor: If the liquor be then evaporated, 
 it becomes brown, is difficultly brought to drynefs, anddepofites a faline fedi- 
 ment. The oil, mixed with Aqua regia, fettles alfo to the bottom. With 
 ffrong Spirit of Nitre, it does the fame; but on digefdon it is diflolved : The 
 liquor becomes brown in evaporation, and is difficultly exficcated, but yields no 
 fediment •, diluted afrefh with water, it appears yellow. Alcalies, both fixed 
 and volatile, added to the oil, occafion a precipitation. 
 
 Spirit of Salt poured upon Orpiment in powder, makes a (light effervefcence, With difTe° 
 but no folution or change enfues ; the fulphureous part of the mineral defending rent acids, 
 the metallic from the action of the acid. Orpiment being mixed with Aqua 
 fortis into the confidence of a pafte, an effervefcence begins after Handing 
 about half an hour, and nitrous vapours plentifully arife, till all the acid is 
 diffipated : The refiduum being moiHened afrefh with Aqua fortis, the fame 
 ph'aenomena fucceed, and the matter afterwards grows hard : Even if ten parts 
 of the acid are employed to one of Orpiment, nitrous vapours conftantly and 
 copioufly exhale. If a little of the mixture be fet to fhoot, fome fine cryHals 
 like hairs are obtained : If the mafs be evaporated to drynefs, it will liquefy on 
 Handing in a cellar, and being then mixed with a large portion of Aqua fortis, 
 occafions at firH a flight effervefcence, without any further change. It is pretty 
 remarkable, that a large quantity of Aqua fortis added at firH to the Orpi- 
 ment, has no effect. Oil or Vitriol, by coition and abflraction from Orpiment, 
 partly difiblves it : The late profelfor Schulze, at Flail, obferves, that equal 
 parts of Orpiment and Oil of Vitriol, fet to diHii in a ffrong fire, yielded at 
 firH a phlegm, and afterwards a fubflance like an oil, fmelling like Opium ; a 
 fmall portion of an affiy matter being left in the retort. When Arfenic is 
 treated with Oil of Vitriol, there arifes a little Sublimate refembling plumousr 
 Alum, which deferves further examination : See Hoffman’s Obfervationes phjf. 
 chem. Aqua regia does not aft upon Orpiment any more than fpirit of Salt 
 except that a little of the arfenical matter may be extracted by the nitrous fpi- 
 ffiit in the compound acid. TheRegulus, and white flowers, diffolve more- 
 
 safrly S) 
 
15 8 
 
 Orpiment 
 
 Pyrophoras, 
 
 Not poifo il- 
 eus. 
 
 Depilatory. 
 
 Ufe as a Pig- 
 ment, LV. 
 
 Metallic Bodies. 
 
 •eafiiy, both in the nitrous and marine acid, and in compofitions of them. Spi- 
 rit of Sal ammoniac, all urinous fpirits, diftilled and expreffed oils, extrad: 
 from Orpiment a yellow tindture; thefe menftrua diffolving its fulphureous 
 part. 
 
 Hoffman diftilled Orpiment with common Salt, and obtained firft an acid 
 phlegm, afterwards yellow flowers, and at length, in a ftrong fire, a tran- 
 fparent red mafs, which adhered to the Tides of the glafs. Glauber diffolved it 
 in- the liquamen of fixed Nitre, mixed thefolution with the fecretSal ammoniac, 
 and on difliiling the mixture, gained an acidulous and urinous phiegm, after- 
 wards a ponderous, yellow, unctuous liquid refembling vegetable oils, and at 
 la ft a blood-red tranfparent Sublimate like an oriental ruby. Kunckel relates, 
 that Orpiment diftilled with Nitre in a tubulated retort, yields a nitrous and 
 fulphureous fpirit, participating of Arfenic, with a large quantity of flowers ; 
 'and that white Arfenic, with equal or thrice its weight of Nitre, injected into a 
 red-hot tubulated retort, yields a like fpirit, but ftronger, and of a bluifh colour," 
 which diffolves metals, and whitens Copper. Meuder informs us, that Orpi- 
 ment being fublimed with an equal quantity of Iron filings, and ten parts of 
 the Sublimate ground on a ftone with twelve parts of cryftals of Silver ; the 
 mixture laid on a piece of paper, inftandy took fire.” 
 
 This mineral, though it manifeftly contains Arfenic, is not found to be 
 poifonous ; the Arfenic being corrected and mitigated by the large proportion 
 of Sulphur, in the fame manner as the virulence of Regulus of Antimony is 
 obtunded by that concrete : Pure white Arfenic, combined with equal its weight 
 of Sulphur, lofes its poifonous quality, and becomes innocent. 
 
 Four ounces of Quick- lime, an ounce and a half of Orpiment, an 
 ounce of Florence orris root, half an ounce of Nitre and half an ounce of 
 Sulphur, boiled, with a ftrong ley drawn from the arhes of bean ftaiks, till 
 the matter becomes confident, then mixed with half an ounce of Oil of Spike, 
 make the common compofition for taking off hair; the part being afterwards 
 anointed with Oil of Rofes. Strong Sope-leys are an equaliy effectual, and 
 more Ample depilatory. It is laid, that the juice of henbane prevents the 
 growth of hair. 
 
 The principal ufe of Orpiment is, as a colouring drug, among the paint- 
 ers, book- binders, &c. Of itfelf it makes a gold-coloured Pigment ; with 
 Indigo or other blues, a green: It is commonly tempered with yelk of eggs 
 and a little faffron, or with fifh galls. At Rouen, it is uled for ftaining 
 wood of the colour of boxwood. It is mixed alfo with wax, employed 
 for heightening the colour of Gold, for hardening Lead in order to the mak- 
 ing of finot, and for colouring glafs, as may be feen in KunckePs Ars vitriaria. 
 Equal parts of Arfenic, Mercury, Tin and Sal ammoniac, are faid to afford in 
 .fublimadon a purple- coloured Pigment. 
 
 SECT. 
 
E J S9 3 
 
 SECT. III. 
 
 MINERAL SALTS. 
 
 T HERE are two general dalles of fimple Salts, Acids and Alcalies. S a l t s? 
 Acids are diftinguiflied by their four tafte ; effervefcing with and dif- 
 folving certain earths, as the allies of vegetables-, and changing the Simple Salts, 
 colour of the blue flowers of plants or their infuflons to a red. Alcalies are aci ^ arui a -* 
 diftinguilhed by a pungent tafte, extremely different from fournefs ; by their ai ' ‘ 
 deftroying the acidity of every kind of four liquor-, diffolving Sulphur by 
 boiling j and changing the colour of blue and red flowers to a green. Liquors 
 impregnated with one kind of Salt raife an effervefcence on being mixed with 
 thofe of the other, greater or lefs in proportion to their ftrength. Subftances 
 diftolved in one are precipitated by the other and in this cafe often there 
 happens no effervefcence upon mixture. In whatever manner they are mixed, Neutral Salts, 
 the Acid and Alcali unite into one uniform neutral compound, giving no marks 
 either of one or the other. When thus combined, in fuch proportions as that 
 neither may prevail,, they are faid to be faturated with one another, or mixed 
 to the point of faiuration. This term is applied alfo to the folution of diffe- 
 rent fubftances in thefe or other liquors : Thus when a liquor has diftolved as 
 much of any body as it is capable of holding fufpended, it is faid to be faturated 
 with that body. 
 
 In the mineral kingdom there are three kinds of acids, naturally blended Different 
 with alcalies, earths, metals or other bodies, into neutral and other faline con- kindsofacids, 
 cretes. The fubjedls from which thefe acids have been moft commonly ex- 
 traded are, Vitriol, Nitre, and Sea-falt -, and hence they are diftinguilhed by 
 the names of vitriolic ^ nitrous and, marine. All the three are volatile in the 
 fire, totally exhaling, when pure, in a heat below ignition; though when 
 combined with fixed bodies, they refift a much ftronger heat, and from fome 
 areicarceto be difunited by any degree of fire. The nitrous and marine acids 
 are always obtained in the form of a thin liquor, the acid Salt beiqg blended 
 with a large proportion of water, without which it would be diffufed into an 
 incoercible vapour. The vitriolic ftands in need of fo much lefs water for its 
 condenfation, as to aflame commonly a thick, and in fome circumftances a 
 folid confidence. 
 
 Alcaline Salts are of two kinds -, one fixed in a ftrong fire ; the other volatile anc j 0 f a ] ca „ 
 in a gentle warmth. The prcdudion of thefe from vegetables and animals lies, 
 will be treated of hereafter. We final 1 here only obferve, that, volatile alcalies 
 are very rarely met with in the mineral kingdom -, but that a peculiar fixed 
 alcali differing from thofe of vegetables is often found in combination with the 
 marine and vitriolic acids. 
 
 CLASS 
 
j;6q 
 
 'Mineral Salt 
 
 CLASS I. 
 
 Vitriolic Acid and its combinations. 
 
 Vitriolic H E vitriolic acid is diffu fed throughout the earth, the waters of the 
 Acid.' JL ocean, and the atmofpherical regions ; and is fuppofed by fome to be 
 v —— t ^ ie ^ a ^ 1S t ^ >e 0t ^ er ac ’^ s both m ineral and vegetable : Whence it is 
 
 named by the chemifts, the univerfal, primogenial, vague acid. In the mi- 
 jed„ ** neral kingdom, it is found in great abundance ; not in a feparate or pure ftate, 
 but combined with various other bodies; with the inflammable principle, into 
 Sulphur; with certain metals, into vitriols; with mineral alcalies, into the 
 Salt called Sal mirabile ; with one kind of earth into Alum ; with another, 
 into felenitic concretes. Argillaceous earths, the coloured earths and ftones, 
 metallic ores, the folid bitumens, the mineral oils and waters,' are all impreg- 
 nated, more or lefs, with this acid or its combinations. • Fixt alcaline Salts 
 imbibe it from the air ; and thus are changed in part into a neutral Salt, fimi- 
 Jar on all trials to one prepared by combining the alcali diredtly with the com- 
 mon vitriolic acid. 
 
 When this acid is united with alcaline Salts either fixed or volatile, it cannot 
 be expelled from them by any degree of fire: Kor is it feparable any other- 
 
 wife, than by transferring it into fome third body, with which it has a greater 
 appetite of union. From fundry earths, we can force it out by fire alone; 
 and from the metallic bodies, with which it is naturally united into Vitriol, 
 Fill more eafily, though fcarce totally; a part of the acid being retained both 
 by the metals and earths, after the adtion of a very vehement fire. It is from 
 Vitriol, that this acid has hitherto been chiefly extradled for common ufes ; 
 whence its name vitriolic . When very largely diluted with water, fo as to be 
 but juft fenfibly acid, it is called phlegm \ when lefs diluted, or more acid, 
 fpirit ; and when fo little diluted, or fo far freed from water, as to aflfume a 
 thick confidence, oil, of Vitriol. 
 
 Gravity. Oil of Vitriol is the moft ponderous of all known fluids, except Quickfilver 
 and fome metallic folutions : Fahrenheit determines its fpecific gravity to be to 
 Fixity. that of water as 18,775 to 10,000. It is confiderably more fixed than any of 
 the other acids; emitting no fumes or fmell in the greateft heat of the atmo- 
 fphere, or even in that of boiling water ; and requiring, to make it boil or diftil, 
 a much ftronger fire than any other faline liquor, a fire almoft fufftcient to 
 make the containing veflel red hot. 
 
 Imbibes moi- Expofed to the air, it imbibes humidity, fo as to acquire a notable aug- 
 fmre from tne mentation of its weight, greater or lefs, looner or later, according as thefur- 
 face of the liquor is larger or fmaller, and the atmofphere itfelf more or lefs 
 moift. Dr. Gould, profefifor at Oxford, relates, that three drams of Oil of 
 Vitriol acquired, in fifty-feven days, an increafe of fix drams and a half [m). 
 
 Floffinan 
 
 ( m ) Dr. Gould’s experiments of Oil of Vitriol 
 imbibing moijlure from the air.] The doctor 
 further informs us, that the increafe in the 
 
 firft day, was upwards of one dram ; in the 
 following days, lefs and lefs ; till, on the 
 fifty-fixth, it fcarce amounted to half a 
 
 grain ; 
 
M I N E R A L S A L T S. l6l 
 
 Hoffman abferves, that an ounce and two fcruples, in an open glafs difh, Vitriolic 
 gained, in fourteen days, feven drams and a fcruple. I expofed an ounce to Acid. 
 the air, in a low glafs body, from September 1736 to September 1737: At 
 the end of the twelvemonth, it weighed feven ounces and two drams, and thus 
 had attracted from the air above fix times its own weight of moifture. 
 
 If Oil of Vitriol and water are mingled hadily together, the mixture be- R a ;f e s heat 
 comes inftantly fo hot as to render the vefifel infupportable to the hand (n). with. water 
 Great caution is requifite in mixing any kind of liquor with this acid ; Jell the and lce - 
 glafs fhould crack from the fudden heat which it produces, or a part of the 
 matter be thrown about with violence during the ebullition, to the manifed 
 danger of the operator : We fhould always add the acid, by little and little at 
 a time to the other liquor, and never attempt to pour the latter into the for- 
 mer. It is obfervable, that a piece of ice, laid on the furface of Oil of Vitriol, 
 foon melts, and when melted, flows didinCt above the acid : If the ice and the 
 acid are fhaken together, they incorporate and grow hot, as when the acid is 
 mixed with water. 
 
 The vitriolic acid, diluted with water, drongly retains a conffderable quan- strongly 
 tity of the aqueous fluid; preventing its exhalation in a heat wherein pure tains water, 
 water would foon be diflipated; and ariflng in part along with it by a fire in- 
 fufficient to elevate the undiluted acid. The further it is diluted, the more 
 eafily it evaporates. 
 
 Oil of Vitriol is capable of being fo far freed from water, as to aflume a Reduced to a 
 folid, butyraceous or icy confidence. I have examined this point with particu- folid Hate, 
 lar care, as it has been greatly controverted, and feems to have been milrepre- 
 fented by all the chemical writers; fome affirming, that the vitriolic acid, 
 when highly concentrated, freezes in winter, and in winter only ; and others, 
 as Stahl, that it never congeals at all, unlefs extremely diluted with water. I 
 found, that common Oil of Vitriol continued fluid in the winter as well as in 
 fummer; that a more concentrated oil, which continued fluid during the hum- 
 mer, congealed in winter ; and that when the acid is dill further freed from 
 phlegm, it becomes confident in the hotted weather. Put fome good Oil 
 of Vitriol into a glafs retort, didil od' about three-fourths of it, and let the re- 
 maining fourth be clofely fecured from the air: The acid thus concentrated 
 will, at any feafon of the year, look like butter or ice by the time it is grown 
 cool. A certain chemid thought to obtain this coagulated oil, without the 
 trouble of didillation in a retort, by evaporating the more phlegmatic part of 
 
 common 
 
 grain : That this experiment was made in 
 a glafs of three inches diameter : That the 
 fame quantity of the acid, expofed to the 
 air at the fame time, in a glafs of only one 
 inch, gained but one ninth fo much as the 
 other, which is exactly the proportion of 
 their furfaces : That the liquor, when fatu- 
 rated with humidity, retained, or loft part 
 of its acquired weight, according as the 
 air was moift or dry ; and that this difference 
 * Phil Tranf N a 1 56. 
 
 was fo fenfible ? as to afford an accurate 
 hygrometer *. 
 
 [n] Heat from the mixture of Oil of Vitriol 
 and water.] About equal parts, by weight, of 
 the two liquors, produce the greateft heat. 
 Hoffmann fays in one place equal parts, in 
 another one part of the acid to two of 
 water f : Probably in the rirft he means by 
 weight, in the latter by meafure. 
 
 t Hoffm. Ohf. phyfco-chetfi. p. 15.0, 167. 
 
 Y 
 
162 
 
 Mineral Salt 
 
 Vitriolic common Oil of Vitriol in an open glafs: He complained to me, that though 
 Acid. . he had feen a good quantity of vapours exhale, the remaining liquor, when 
 grown thoroughly cold, not only refufed to coagulate, but weighed as much 
 as atfirfh The caule was obvious : The Oil of Vitriol, ever greedy of humi- 
 dity, had imbibed as much from the air, as it had loft in the fire. The lame 
 individual liquor being put into a retort, and about one half diftilled off; the 
 refiduum, excluded from the air, affumed now a confident form. 
 
 Quantity of Oil of Vitriol faturates a larger quantity of fixed alcaline Salt than any other 
 rate''* ancTof 30 ^ : ^' ve P arts 0ie,: h' s ac ^ are Sufficient for eight or more of the alcali, whilft 
 pure’acidit the ftrongeft of the others is incapable of Satiating its own weight (<?). The 
 contains. acid part of the liquor being here abforbed by the alcali, its aqueous part is fet 
 at liberty, fo as to arife with eale in evaporation or diftii lation. The diftilled 
 fluid, though it has no manifeft tafte, is laid to differ in fome refpeds from 
 pure water-, to be more fubtile and penetrating, and to exhale much fooner in 
 an equal degree of heat : It is called by Niednerus, fpiritus mundi (p). The re- 
 maining Salt, perfectly exficcated, difcovers, by its increafe of weight above 
 that of the dry alcali employed, the quantity of ialine matter it has received 
 from the acid liquor, and consequently the proportion of pure acid which that 
 liquor contains. By this method, an ounce of good Oil of Vitriol is found to 
 confift of about five drams of acid, and three of water. 
 
 The vitriolic acid lofes its attraction for water, by the union of any of thofe 
 fubftances which are capable of being combined with it ; even of thofe, which, 
 Separately, are as greedy of humidity as itfelf, as fixed alcaline Salts ; and cf 
 thofe by which all other acids acquire the property of attracting moifture, as cal- 
 careous earths. It never promotes the fufibiiity or volatility of bodies, as the 
 others in many inftancesdo ; but on the contrary retards fufion, and increafes 
 fixity. Thus vegetable fixt alcaline Salts, a powerful flux for fundry refractory 
 matters, and which flow eafily when Saturated with other acids •, earths and 
 metals, which with other acids yield compounds eafy of fufion ; when com- 
 bined with the vitriolic, cannot be made to melt at all. 
 
 The vitriolic is the moft powerful of all the acids ; though there are many 
 fubftances, which it does not act upon fo violently, or diffolve fo readily, as 
 fome of the others do ,{q). If any other acid be combined with an alcaline 
 
 Salt, 
 
 General rela- 
 tions to other 
 bodies. 
 
 Expels all 
 other acids 
 from alcalies 
 and, earths. 
 
 (o) Alcali faturated by Oil of Vitriol.] It is 
 obfervable, that this acid does not Saturate 
 To much, by one half or more, of volatile 
 alcaline Salts, as it does of the fixed. The 
 nitrous acid feems to fatiate a larger propor- 
 tion of volatile alcalies than the vitriolic. 
 
 ( p ) Water dif tiled from Oil of Vitriol and 
 Salt of Tartar.] This liquor is faid alfo to 
 diftolve leaf-gold ; and when drank, even 
 in a dofe of a fpoonful, to excite a diapho- 
 lefis. I have tried it with Gold, but could 
 not obferve that it had any action on that 
 metal. 
 
 5 
 
 (y) Vitriolic acid moJT powerful.] The power - 
 fulneft , activity , and Jlrength of acids, are to 
 be carefully diftinguifhed ; as being three 
 properties independent of one another, 
 though commonly confounded together. 
 The vitriolic is more powerful than any of 
 the others, as it expels them all from alca- 
 line Salts both fixed and volatile, and from 
 the foluble earths ; and takes pofieffion it- 
 felf of the Alcali or earth. It is lefs adiive , 
 or adls more languidly and difficultly, upon 
 moft bodies, than either the nitrous or ma- 
 rine. In its concentrated ftate, it is the 
 frongef of acids, as containing the largeft 
 
 quantity 
 
Mineral Salts. 163 
 
 Salt, the addition of the vitriolic will take the alcali from it: The acid before Vitriolic 
 combined, though it could not be expelled by fire alone, will now readily ex- Acid. 
 
 hale, and leave the vitriolic in pofTeilion of the alcali. On this principle de- -v~— 
 pends the diftiliation of the acid fpirits of Nitre and Sea-fair. Hence alfo we 
 are furnifhed with a method of difcovering which of the mineral acids any 
 compound Salt contains : Oil of Vitriol has noa&ion on thofe, which hold no 
 other acid than the vitriolic itfelf, but effervefces with the others, and imme- 
 diately extricates a part of the acid in vapours: The particular acid may be 
 diflinguifhed by the colour and fmell of the fumes. 
 
 The vitriolic acid retards fermentation and putrefadtion ; but has this effVTjjow it in flu- 
 in a lefs degree than the other acids, whether employed in its pure ftate, or ences fermen- 
 combined with other bodies : How little it is difpofed to prevent putrefaction tatl0n and P u “ 
 when united with certain metals, appears from the mouldinefs to which com- treia ^ oa ” 
 mon ink is fubjedt. 
 
 Hoffman obferves, that the concentrated acid, or Oil of Vitriol, applied Applied to 
 flightly and fuperficially to the fkin of a living animal, raifes a violent burning the human 
 heat and pain ; but that a larger quantity, preffed clofe on the part, fo as to boc T 
 prevent the ingrefs of the aereal moifture, occafions little pain or erofion : If 
 the oil is diluted with a little water, it proves corrofive in either cafe. 
 
 The vitriolic acid, largely diluted with water, is employed medicinally for Medical u fe$’ 
 preventing a putrefadlive difpofition, corredhng bilious acrimony, abating 
 heat, quenching thirft ; in debilities of the ftomach, and in the heartburn. 
 
 To perfons of weak or unfound lungs, to women who give fuck, to hydropic 
 and emaciated perfons, it is injurious. Some recommend it as a collyrium for 
 fore eyes •, but as it coagulates the animal juices, and corrodes and indurates 
 the folids, it is furely very unfit for being applied to that tender organ. 
 
 Article I. 
 
 Combination of the vitriolic acid with inflammable matter . 
 
 O IL of Vitriol, however limpid and clear, becomes yellowifh, brown, Becomes co- 
 reddilh, black, from the bare contact of any inflammable matter, as a loured from 
 fmall bit of cork, paper, wax, bladder, or other like fubllances, which give ^econma of 
 no confiderable tinfture to any liquor befides : The whiteft camphor and fu- fubflTnees 516 
 gar, the moft limpid effential oils and diftilled inflammable fpirits, have the 
 fame effeft. It is obfervable that fome fubftances, as Camphor and Oil of 
 Turpentine, give a colour to the acid only in its concentrated ftate •, and that 
 the colour produced difappears again upon diluting the liquor. Camphor put 
 into Oil of Vitriol, is diffolved by it, lofes its own ftrong penetrating fmell, 
 and renders the liquor black like pitch : On adding a quantity of water to the 
 
 pitchy 
 
 quantity of pure acid in proportion to the increafed. Vegetable acids may be made 
 phlegm or water. However weakened by Jlronger than the marine, but Hill continue 
 dilution, it ftill continues the moft powerful', lefs powerful , as being expelled by it from. 
 
 By thus weakening it, its activity is oftentimes alcalies and earths. 
 
 Y 2 
 
164 
 
 Miner 
 
 a L 
 
 ALTS. 
 
 V itrioljc pitchy mixt, the Camphor inftantly recovers its odour, and the acid its colour- 
 Acid. j e f s pellucidity, 
 
 lVcnoniena ; Oil of Vitriol, dropt into eight times its weight or more of highly re&ified 
 with vinous Spirit of Wine, by a little at a time to prevent any immoderate ebullition or 
 fpirits. difcharge of vapours, forms with it on digeftion for fome days, a redd ilia li- 
 
 quor ; which being committed to diftillation, great part of the acid arifes along 
 with the vinous fpirit by a very gentle heat •, an acid, bituminous, lulphureous 
 matter remaining. The diftiiled liquor, impregnated with the volatilized Oil 
 of Vitriol, has a fragrant fmell, and dilcovers no acidity to the tafte; and 
 hence is called dulcified Spirit of Vitriol: In length of time, however, its fra- 
 grance diminifhes, and the latent acid begins to refume its acidity. 
 
 With oils. Oil of Vitriol, mixed with diftiiled oils, occafions great hear, effervefcence, 
 and lulphureous fumes^ and unites with the oil into a dark coloured mafs, 
 like Pitch or Bitumen, from which a portion of Sulphur is producible. On 
 expreffed oils, it acts much lels violently than on the diftiiled. An account of 
 its particular effects on different oils may be feen in Hoffman’s Obfiervationes 
 Chemica. 
 
 Volatilized. In the extraction of the vitriolic acid from Vitriol or other fixed bodies by 
 vehemence of heat ; if the diftilling veffel had any fifture, or contracted any in 
 the fire, the acid receives a remarkable alteration. It now proves extremely 
 volatile; emitting pungent and almoft fuffbeating vapours in the air, and to- 
 tally arifing in diftillation by a heat fcarce too great for the hand to bear. It is 
 fo much lei’s corrofive than the acid in its fixed ftate, as to be lafely tafted ; 
 when it difeovers only a flight biting bitterifhnefs and roughnefs, with fcarce 
 any fenfible acidity. It neutralizes fixed alcaline Salts ; but inftead of ex- 
 pelling, it is itfelf expelled from them by both the other mineral acids (r). 
 This volatile fpirit, kept for fome time in a veffel not clofely ftopt, lofes its 
 fuffbeating odour, refumes its fixity, acidity, and all its former qualities. 
 Production of The vitriolic acid, freed from phlegm, and combined by fire with a due 
 Sulphur. proportion of any inflammable matter, is changed into a folid, infipid con- 
 crete Sulphur. Thus when the concentrated acid is mixed with oils, and the 
 phlegmatic part drawn off, a true Sulphur may be fublimed from the refiduum. 
 If the acid be faturated with an alcaline Salt, as the alcali of Sea fait with which 
 it forms a fufible compound, the aqueous part of the mixture evaporated, and 
 the remaining Salt (called Salmirabile ) melted with fome powdered charcoal ; 
 the refult will be, not a combination of the Alcali and vitriolic acid as at firft, 
 but of Alcali and Sulphur ; from which the Sulphur is eafily feparable by folu- 
 tion in water, and precipitation with any acid. 
 
 (r) Volatile Spirit of Vitriol.'] This fpirit, 
 though it fcarce difeovers any acidity to the 
 tafte, raifes a confiderable effervefcence with 
 alcaline Salts both fixed and volatile, and 
 faturates a large proportion of them : It in- 
 ftantly lofes its pungent odour on the ad- 
 mixture of the Alcali : The mixture fhoots 
 into fmall cryftals, which, on the affufioa 
 
 of any other acid, yield up the vitriolic 
 again, as volatile and fuffocating as it was 
 received. This fpirit deftroys or whitens 
 the blue and red colours of the flowers of 
 plants; whilft in its fixed ftate, like other 
 acids, it changes the blue to red, and 
 heightens thofe which were naturally of that 
 colour. 
 
 SUL- 
 
Mineral Salts. 
 
 Sulphur. 
 
 SULPHUR or BRIMSTONE. ' ■ — J 
 
 'J'HE name Sulphur has been applied by iome to the inflammable principle 
 of bodies ; by others, to all inflammable mixes, or fubftances participat- 
 ing of this principle ; and the alchemifts fpeak alfo of a Sulphur that does not 
 burn. Vegetable oils and refins, animal fats, mineral bitumens, afe by fome 
 called Sulphurs; and by fome, Sulphur itfelf is referred to the bitumens. This 
 confufion has given rife to numerous errors and abfurdities : How widely diffe- 
 rent is true Sulphur, in all its properties, from bitumens, or oils, or any other 
 kind of inflammable body ! If every thing that burns was to be called Sulphur, 
 we might with equal propriety call every thing that is liquid by the name of 
 water, or of fpirit of wine, or vinegar, or oil, or any other particular liquor. 
 Experiment has fully evinced, that Sulphur is no other than the concentrated 
 vitriolic acid combined with a fmall proportion of the phlogiftic or inflam- 
 mable principle; and to this combination alone, which is always one and the 
 fame excepting for adventitious admixtures, the more judicious chemifts have 
 wholly confined the name. 
 
 Sulphur is a folid brittle concrete, of a yellow colour inclining a little to General pro- 
 greenifh, in fome degree gloffy. Held in the warm hand, it crackles, orP erties * 
 burfts : and leaves on the hand a particular kind of fmelh It is nearly twice 
 as heavy as an equal bulk of water. 
 
 It melts in a fmall degree of heat into a red pellucid fluid, and on cooling Fafion. 
 concretes again into its original appearance. Some have endeavoured to pu- 
 rify Sulphur from the droffy matters which are often mixed with it, by melt- 
 ing and pouring it into Spirit of Wine: Others have melted it with wax, and 
 poured the fluid mixture into water, when the Sulphur fubfides, and the wax 
 arifes to the furface, carrying up with it a part of the impurities. With re- 
 gard to Spirit of Wine, it can have no effeCl in feparating foreign matters from 
 the Sulphur, though it feems in fome meafure to heighten the yellow colour. 
 
 Wax on the other hand renders it greener, and if the fufion is feveral times 
 repeated, changes it quite blackifh. 
 
 Sulphur kept in fufion, gradually exhales : If the air is excluded, it fub- Sublimation, 
 limes into the upper part of the veffel, without undergoing any other altera- 
 tion, than being reduced into the form of powder or flowers. This property 
 affords a method of purifying it effectually from earthy, ftony, or other fixed 
 matters ; and at the fame time of reducing it into a finer powder than can eafily 
 be obtained by trituration. Where only a fmall quantity of flowers of Sulphur 
 is wanted, the fublimation may be performed in ajar, with aludels clofely 
 luted upon it, and a blind-head at top. In England, they are prepared by 
 particular perfons in the way of trade: The fubliming veffel is an Iron pot, 
 fo large as to hold two or three hundred weight or more of Sulphur, about a 
 fourth of its capacity remaining empty : The recipient is an arched room built 
 above the pot, and communicating with it at one fide by an aperture of fix or 
 eight or more inches in diameter. The room is lined with glazed tiles ; and 
 furnifhed with a door, by which a man may creep in, when the operation is 
 finifhed, to fweep out the flowers. In the middle of the door is a lmall hole, 
 
 which 
 
i66 
 
 Mineral Salts. 
 
 Sulphur, which is opened occafionally during the fublimation, for examining whether 
 the flowers continue or have ceafed to arife. 
 
 Acid fpirit. In open veflels, Sulphur readily takes fire from the contaCt of ignited bo- 
 dies, and if kept in fufion, burns entirely away, with a blue flame, and a 
 diffufive fuffocating fume (j). Thi . fume is no other than the vitriolic acid 
 volatilized by the flame : A confiderable quantity of it may be detained, and 
 condenfed into a liquid form, by placing over the burning Sulphur capacious 
 glafs veflels, replete with aqueous vapours : The larger the receivers, and the 
 lels communication the flame has with the external air, the more of the fumes 
 will be prefer ved. 
 
 Methods of The molt common apparatus for this purpofe confifls of a little earthen 
 'collecting the difh, for burning the Sulphur in •, a glafs bell, fufpended over the flame ; and 
 acicl " a broad glafs or earthen veflel, which fupports the difh with the Sulphur, and 
 
 receives the acid liquor as ic drops from the fides of the bell. Many variati- 
 ons have been made in this apparatus, with a view to detain the fumes more 
 effectually. Infleadof the bell (from which the acid has received the name of 
 Spiritus fulphuris per camp ana <n ) fome have employed a glafs differing from that 
 fnape in having a rim turned in at the bottom, and a tube at the top, to which 
 a receiver is fitted as an enlargement of the capacity of the veflel •, others a 
 retort, with its bottom cut out, and a glafs body or tubulated receiver a, -plied 
 to its neck-, others a receiver, with a hole in its bottom for admitting the 
 flame ; others a glafs body, with fome water in its bottom, holes in the fides, a 
 crucible with burning Sulphur placed in the water, and another body inverted 
 on the mouth : Some have fufpended the burning Sulphur in a wooden cafk 
 
 half full of water, and afterwards rectified the liquor. The grand difficulty is, 
 that Sulphur will not burn without a draught of air, and the acid fumes $re fo 
 volatile that far the greateft part of them is carried off by the air. Some di- 
 rect a little Nitre to be mixed with the Sulphur, to promote its burning 5 
 but though Nitre is undoubtedly of advantage in that refpeCt, it is injurious in 
 another-, rendering the produCt impure, by giving out its own acid along with 
 that of the Sulphur. Many other contrivances have been made, but none 
 with any commendable fuccefs; the fame acid being obtainable at a much 
 cheaper rate from Vitriol, than by any of the methods of procedure to which 
 Sulphur has hitherto been fubmitted [t). The belt way hitherto difeovered of 
 
 collecting 
 
 (5) Inflammability of Sulphur.'] Stahl ob- 
 serves, that an ounce of Sulphur, burnt 
 with a wick, may be made to yield a con- 
 ftant flame, for fix hours ; and that, when 
 the wick was very fmall, only fifteen or 
 fixteen grains were confunied in an hour. 
 See Stahlii exp . CCC numero chymicee IS phy- 
 flcce. 
 
 ( t ) Method of collecting the acid of Sulphur..] 
 This procefs has of late been fo far im- 
 proved, by fome particular perfons, as to 
 furnifh, at a very low price, almoft all the 
 acid now fold under the name of Oil of 
 Vitriol. The improvement confifts, in em- 
 
 ploying very large glafs veflels of the ca- 
 pacity of a hogfhead or more, in which is 
 placed a little water, whofe fleam collects 
 and condenfes the fumes ; but principally 
 in mixing with the Sulphur a fmall portion 
 of Nitre, about fix pounds to an hundred 
 weight, which enables it to burn much 
 more fpeedily than Sulphur by itfelf, and 
 without communication with the external 
 air : By this means nearly all the fumes 
 are preferved. It does not appear, that the 
 fpirit thus colledled contains any of the ni- 
 trous acid ■, for the acid of Nitre is de- 
 flroyed by deflagration. See Nitre. 
 
Mineral Salts. 167 
 
 ccliedting the acid fpirit of Sulphur in a volatile date,. is that given by Sulphur. 
 Stahl : 1 he Sulphur is made to burn (lowly by means of a wick, a number of 
 aludels fet over it, and a cloth moiftened with drong alcaline ley placed in 
 each aludel : As foon as any ot the clothes become dry, a moift one is put in 
 its room. The alcaiine Salt which the clothes were impregnated with, imbibes 
 the acid fumes, and is thus converted into a neutral Salt, which is eafily rub- 
 bed out. It is the volatile vitriolic acid that this Salt contains •, and hence, 
 upon adding to it common Oil of Vitriol, in a tubulated retort, the volatile 
 fpirit diftils, leaving the Alcali combined with the more powerful fixed acid 
 fuperadded. The volatile however, as well as the fixed acid, is Hill more 
 commodioufly and advantageoufiy obtainable from Vitriol itfelf. 
 
 It was formerly fuppofed, that the acid fpirits of Vitriol and Sulphur were j ts ac :.j £ j, e 
 really different from one another, and hence they were received in the (bops as fame with 
 ■ two diftindt acids : Their identity is evident from hence ; that the fpirit ob • th . at °f Vi- 
 
 tamed from common Sulphur, united with metals, forms a true Vitriol ; and trio! ’ 
 the fpirit extracted from common Vitriol forms, with inflammable fubfiances, 
 a perfect Sulphur, not didinguilhable on any trial from pure mineral Brim- 
 Hone. We (hall fee hereafter, that common Vitriol is a production from ful- 
 phureous minerals ; and that the acid of the Vitriol is the very individual acid, 
 which before entered the compofition of the Sulphur. 
 
 Sulphur does not diffolve in water, in Spirit of Wine, or in acid liquors : Menftrua of 
 The vitriolic acid, neverthelefs, extracts a part of the acid of the Sulphur, fo Sul P !lun 
 as to gain a confiderable increafe of its own acidity (u). Fixed alcaline Salts, 
 injected upon half their weight or lefs of melted Sulphur, readily unite with it 
 into a red or liver-coloured mafs, called hepar fulphuris , which deliquiates in 
 the air, difiolves in water, and gives a golden tindture to Spirit of Wine : The 
 watery folution, kept for fome time, generally depofites a black powder : Sul- 
 phur is diffolved alfo by boiling in fixt alcaline Lixivia, or in Lime-water. 
 
 The addition of any acid to thefe folutions, renders them milky, and precipi- 
 tates the Sulphur in form of a white powder called lac fulphuris : During the 
 precipitation, an extremely fetid vapour arifes, which blackens metalline uten- 
 fils, particularly filver ones, at a confiderable diftance (x). 
 
 If the mixture of Sulphur and fixed alcaline Salt, be reduced to powder, Refolution of 
 kept for fome time in a gentle heat, and frequently ftirred ; the Sulphur will Sulphur by 
 be deftroyed, or refolved into its condiment parts. The inflammable prim ^ xe< ^ alcalies > 
 ciple is gradually dififipated, and only the acid of the Sulphur remains com- 
 bined 
 
 (u) EffePt of menjlrua, &c.] Sulphur, re- (x) Precipitation from alcalier and Lime.'] 
 peatedly melted and quenched in water, af- The Precipitate, though of a white colour, 
 fumes a degree of tranfparency, but of fhort does not feem to differ in quality from what 
 duration. By treating it in the fame man- the Sulphur was at firft, provided it has 
 ner with Spirit of Wine, its yellow colour, been- carefully walked from the adhering 
 as formerly obferved, is fomewhat improved, faline matter : On fublimation, or fimple 
 
 The marine acid, long boiled on Sulphur fufion, it refumes its original yellow colour, 
 or repeatedly abftradted from Sulphur, is It is obfervable, that fixed alcaline Salts 
 faid to render it confiderably tranfparent ; precipitate Sulphur from the folution made 
 the vitriolic, to make it lefs inflammable, by Quick- lime ; and that the fetid fmell, fo 
 and more fixed in the fire 3 the nitrous, to ftrong in all the precipitations of Sulphur by 
 ©ccafion no change, acids, is not here perceivable. 
 
1 68 
 
 Sulphur. 
 
 Proportions 
 of acid and 
 phlogilion. 
 
 Sulution in 
 volatile fpi- 
 rits. 
 
 Solution in 
 oils : 
 
 Various bal- 
 f'aros. 
 
 ^Mineral Salts. 
 
 bined with the Alcali. Xnftead of a red, fetid, alcaline, fulphureous com- 
 pound, we find now a white, inodorous, neutral Salt, the fame as if common 
 Oil of Vitriol had been mixed with the Alcali. From this experiment we are 
 enabled to determine the proportions of acid and phlogifton of which Sulphur 
 confifts; the increafe of weight which the alcaline Salt acquires being pure 
 concentrated acid. It appears upon careful trial, that in fixteen ounces of 
 Sulphur, there are upwards of fifteen ounces and fix drams of pure vitriolic 
 acid void of phlegm ■, the inflammable matter, by which fo large a quantity of 
 that moft corrofive acid is in all its properties fo furprizingly changed, amount- 
 ing only to about a dram. * 
 
 Some report that Sulphur will diflfolve in volatile alcaline fpirits, without any 
 intermedium. Boerhaave directs, for this purpofe, any ftrong alcaline fpirit 
 to be difiilled from flowers of Sulphur, and cohobated or drawn over a fecond 
 time from the refiduum ; or the mixture to be long kept in a clofe veflel, and 
 frequently fhaken. I tried ftrong fpirits of Sal ammoniac, both Ample and 
 dulcified, prepared both with alcaline Salt and with Quick-lime, and a fpirit fa- 
 turated with Oil of Anifeeds : But none of the five made any folution, or ex- 
 tracted any tincture from the Sulphur, either by digeftion or diftillation. 
 
 There are means, however, of procuring a perfect folution of Sulphur in 
 volatile fpirits ; namely, by mixing the Sulphur, not with the fpirit already 
 prepared, but with crude Sal ammoniac ; and adding Quick-lime to extricate 
 the volatile Alcali, which thus will elevate with it in diftillation a confiderable 
 portion of the Sulphur. Beguinus takes four parts of Sulphur, two of Quick- 
 lime, and one of Sal ammoniac : Hoffmann’s proportions, three parts of Lime, 
 two of Sal ammoniac, and one of Sulphur, fucceeded better with me. The 
 mixture is to be put into a retort, and diftilled by a gradual fire, the jundlure of 
 the retort with the receiver being clofely luted. The diftilled liquor called ful- 
 phureous Spirit of Sal ammoniac, fmoking Spirit of Sulphur, or volatile 
 Tincture of Sulphur, is extremely volatile and penetrating, emits highly fetid 
 vapours, which blacken Silver, and give colour to invifible writings made with 
 faturnine folutions, like the liquor of Orpiment, page 155. It is employed 
 medicinally in fome compofitions ; internally as a fudorific, and externally as 
 an antipodagric. 
 
 Sulphur diffolves in oils, by the afliftance of a boiling heat, into a thick, 
 yellowifh or reddifh fluid, called Balfam or oily liver of Sulphur. This pro- 
 cefs fhould be performed without doors, in large veflfels 5 the matter conftantly 
 watched and ftirred, and, if it begins to rife up, removed immediately from 
 the fire : Otherwife the combuftible compound will fuddenly run over into the 
 furnace, and may be productive of terrible confequences : One of my people 
 very narrowly eicaped from fuch an accident with his life, and will carry the 
 effects of it to his grave. 
 
 Expreffed oils diffolve Sulphur far more readily and plentifully than the 
 diftilled. The ballams of Sulphur with diftilled oils, directed in books of 
 pharmacy, are very injudicious preparations; as the oil will fcarcely gain any 
 tincture from the Sulphur, without a boiling heat; and fuch a heat will de- 
 ftroy the flavour and peculiar qualities of the oil. If thefe kinds of preparati- 
 ons are wanted, they may be much more commodioufly and advantageoufly 
 
 obtained 
 
Mineral Salts, 169 
 
 obtained by adding a due proportion of any effential oil to the folution made Sulphur. 
 with expreffed ones. Exprelfed oils will eafily take up half their weight of V— 
 Sulphur, and form with it, when grown cold, a thick confident mafs : It this 
 be liquefied by a gentle heat, and any effential oil added, they will readily in- 
 corporate together. The effential oil of Anifeed differs remarkably from all 
 the other diddled oils, in its power of diffolving Sulphur ; taking up rather 
 more even than the expreffed. This oil, digeded with the hepar fulphuris , or 
 compofitions of Sulphur and fixed alcaline Salts, readily takes up a large quan- 
 tity of Sulphur from theAlcali: Other effential oils abforb very little ; and 
 expreffed ones fcarce any at all. It is obfervable that the balfam of Sulphur 
 with oil of Turpentine, if faturated with the Sulphur whild hot, concretes on 
 cooling into a curious vegetation refembling a tree. 
 
 Sulphur unites in the fire with mod metallic bodies, promotes the fufion ofEffedhofSul- 
 the refractory ones Iron and Copper, renders Lead on the other hand almoftphur on me- 
 unfufible, and debafes the quality of them all. It changes feveral into the ap- tals * 
 pearance of their own ores ; Silver, into a foft leaden coloured fubdance, refem- Artificial ores, 
 bling the malleable diver ore; Iron and Copper into yellowifh concretes, like 
 the natural Pyritte ; the antimonial Regulus into Antimony ; Quickfilver and 
 Arfenic into red compounds, the fame with the native Cinnabar and red Arfe- 
 nic ; Lead, into a dark-coloured mafs, like its common ore ; Tin, into a 
 fubdance like Antimony, a form in which that metal is never found in the 
 earth. Pure Sulphur does not aft upon Gold, but fulphurated Alcali or hepar 
 fulphuris unites with Gold in fufion as well as with other metals, and renders 
 it diffoluble in water fo as to pafs through the pores ot a filter (y). 
 
 The 
 
 ( y ) Effects of Sulphur on metals."] It unites 
 with all the metals and femimetals, except 
 Gold, Platina, and Zinc; but fcarcely adds 
 upon metallic calces, excepting thole of Lead 
 and Nickel. It promotes the fufion of 
 Iron, Copper, Silver, and Regulus of Anti- 
 mony ; and impedes that of Lead, Bifmuth 
 and Tin, particularly of the former. 
 
 Though Sulphur is, by itfelf, very vola- 
 tile in the fire, it adheres fo ftrongly to me- 
 tallic fubftances, as not to be eafily expelled. 
 It is not diffipable from any metal in clofe 
 veffels : In open ones, it may be entirely 
 diffipated from Silver, Tin, Bifmuth, and 
 Regulus of Antimony ; the firft of which it 
 leaves uninjured, or in its perfect metallic 
 form; the others in that of a calx. To 
 Copper of all metals it adheres the mod 
 ftrongly ; and hence the difficulty of ex- 
 tracting pure Copper from its fulphureous 
 ores. The acids which diifolve metals by 
 themfelves, and oils and alcaline liquors, 
 which diffolve Sulphur, do not, unlefs in a 
 few inftances, effectually extradt either when 
 
 combined with the other ; the one defending; 
 the other from the adtion of its appropriated 
 menftrua. 
 
 Different metallic bodies have different 
 degrees of affinity or attraction to Sulphur, 
 Arfenic the leaft. When Sulphur is com- 
 bined with Arfenic, it will part with the 
 Arfenic on adding Quickfilver ; with which 
 laft it remains united at the bottom of the 
 veffel, whilft the Arfenic, more volatile 
 than that compound, fublimes pure. If 
 Regulus of Antimony is joined to the ful- 
 phurated Mercury, the Quickfilver is fet a£ 
 liberty, and diftils by itfelf, leaving the Sul- 
 phur behind in poffeffion of the Regulus. 
 Silver abforbs it from that femimetal, form- 
 ing with the Sulphur a kind of fcoria, which 
 flows diftindt upon the furface. In like 
 manner, Bifmuth takes it up from the Sil- 
 ver; Tin from Bifmuth ; Lead from Tin ; 
 Copper from Lead ; and Iron from all the 
 foregoing: Hence the ufe of iron filings in 
 the allaying and fmelting of fulphureous 
 ores. 
 
 Z 
 
 Fixed 
 
jyo 
 
 Sulphur. 
 
 l ) 
 
 Gunpowder. 
 
 Medical ufe. 
 
 "Natural hif- 
 Sory. 
 
 Red Sulphu: 
 
 Mineral Salts. 
 
 The principal life of Sulphur is in fire-works, and for making gunpowder. 
 The difcovery of gunpowder is attributed by fome to an Englifh monk, Roger 
 Bacon ; by others to a monk of Freyberg, Berthold Schwartz, about the year 
 1380: Whoever was the inventor, the difcovery was doubtlefs accidental ; for 
 who could have expe&ed, from any artificial compofition, the aftonifning 
 etfedls of gunpowder. The ingredients are Nitre, Charcoal and Sulphur, the 
 proportions of which are different in different works, and generally kept a 
 fecret. The Sulphur is commonly in fmalleft quantity, and the Nitre in the 
 krgeft: Some take but one part of Sulphur to feven of Nitre: Others three 
 or four of Nitre to one of Sulphur and one of Charcoal : Others two parts of 
 coals to one of Sulphur. There are differences alfo in the choice of the Char- 
 coal, and the Sulphur, and the purification of the Nitre. Among us, the 
 powder made at Liffa in Poland has been always accounted the befl. Le- 
 mery fays the Sulphur fhould be previoufiy freed from a part of its fixed alca- 
 line Salt : Sulphur has nothing of any fuch Salt to lofe, but it would be pro- 
 per, if it would anfwer in point of expence, to feparate the earthy impurities 
 by fublimation. It is not the Sulphur in the compound that firfi takes fire, 
 as the above-mentioned author imagines, but the Charcoal : I mixed Sulphur 
 and Nitre in fixteen different proportions, but none of the mixtures would take 
 fire from a fpark, without the addition of fome animal or vegetable inflam- 
 mable matter Sulphur is employed likewifein fome woollen manufadlures, 
 
 in bleaching, for making Cinnabar, by the wine-coopers, for fundry cecono- 
 ,mical and other like purpofes It is ufed medicinally againft cutaneous erup- 
 
 tions, and diforders of the lungs : From the virtues attributed to it in this laft 
 intention, it has received the name of anima pulmonum. 
 
 Sulphur is fometimes found native in the earth, in pure, bright yellow, 'femi- 
 tranfparent maffes ; but more commonly in opake ones, of a greenifh, greyifh, 
 or other colours, intermixed with various earthy or ftony matters : Thefe im- 
 pure forts are thofe commonly underftood by the name of Sulphur vivum. The 
 native Sulphurs are met with chiefly about Volcanos in Italy, in fome of the 
 German, Hungarian, and Swedifh mines. A pale yellow tranfparent Sulphur 
 is brought from Guadaloupe in America, and called by the French Soufre de 
 Guadaloupe , de guido, or de quittau. Monardus mentions a Sulphur vivum pra~ 
 Jlantiffimum as he calls it, tranfparent as Glafs, and in colour like Gold. 
 
 . There are likewife reddifh, and red Sulphurs ; of which I have feen fome 
 of a femitranfparent cinnabarine red : Thefe are never to be employed for me- 
 dicinal ufe, as they are rarely free from an admixture of Arfenic, and indeed 
 are rather to be looked upon as a native red Arfenic or Realgar, than as Sul- 
 phurs : The redder the colour, the more Arfenic they generally hold (z). The 
 
 greateft 
 
 Fixed alealine Salts abforb Sulphur in 
 fufion from all the metals ; but as foon as 
 they have taken up the Sulphur, the com- 
 pound which they form with it begins to re- 
 dilfolve the metal. This compound a£ls 
 more powerfully on metals than Sulphur by 
 
 itfelf, entirely deftroys their metallic afpecl, 
 and renders moll of them foluble in water. 
 Zinc is the only metallic fubftance which 
 refills this compofition. 
 
 (z) Arfeniiatecl Sulphur. 1 Here it may be 
 
 obferved. 
 
A L T 6. 
 
 I N E H A L 
 
 I 71 t 
 
 greateft quantities of thefe red arfenical Sulphurs are found in the Turkifh Ao-Sulphur. 
 minions •, and fome in the territories of Saltzburg. 
 
 Authors mention another fort of native Sulphur, which feparates from the 
 hot mineral waters, particularly thofe of Aix-la-chapelle : Whether this yel- 
 low fediment be a true Sulphur or not, I cannot determine, as I have not had 
 an opportunity of examining it. 
 
 Sulphur is an ingredient in mod: kinds of ores, and frequently is the only Sulphur In 
 one by which metallic bodies are debafed in the earth into that form. Tin, ores * 
 Bifmuth, and Cobalt are the only ones which have no Sulphur in their ores : 
 
 Arfenic and Gold are frequently accompanied with it: Silver, a good deal 
 more frequently ; and Lead (till morefo : Of Copper, it is a more conftant at- 
 tendant than of any of the foregoing: Mercury and Regulus of Antimony are 
 never found without it. The common ores oi iron rarely hold any Sulphur: 
 
 The mineral, however, which contains the largeft quantity of Sulphur, or 
 from which the Sulphur is extracted to the greateft advantage, is a ferrugi- 
 neous ore, called, from its colour, and from its drifting fire with Steel, 
 yellow Pyrites. 
 
 The yellow Pyritee are found moft plentifully in fome parts of Sweden, and Method °f ' 
 in Saxony, where the principal Sulphur works are eftablifhed. The Sulphur extrai ^ ln £' 
 is extracted in fome places, by diftiliation in large Iron retorts : In others, by 
 eliquation in earthen veffels; the Sulphur, as it melts out from the ore, being 
 conveyed along inclined pipes into veffels of cold water. At Gofiar in the 
 lower Saxony, great quantities of Sulphur are collected in the calcination of 
 certain ores in the open air : The ore being (Ratified with wood, and the wood 
 feton fire, the Sulphur melts out in different parts of the pile, and is received 
 in veffels placed underneath, or in cavities made for that purpofe in the matter 
 itfelf when foftened by the heat: The rough Sulphur obtained by thefe pro- 
 ceffes is purified by fufion •, which is fometimes twice or thrice repeated : The 
 lighter feculencies, which arife to the furface, are fkimmed off ; and the fluid 
 Sulphur poured from the groffer fediment that falls to the bottom. Moft of 
 the Sulphur prepared in Germany appears of a fine yellow colour, or inclines 
 but a little to greenifh yellow : The Swedifh, particularly that which comes 
 from the ifland Melo, has more of the green, and is not near fo fine. The 
 impure Sulphur, or dregs remaining after the purification, are called Sulphur 
 caballinum , as being only fit for horfes : But even for fuch purpofes, it is furely 
 more advifable to ufe pure Sulphur, than an unequal and an unknown mine- 
 ral medley, which may often do more harm than good. 
 
 Hoffman 
 
 obferved, that moft forts of native Sulphur 
 participate of Arfenic ; though the quan- 
 tity of Arfenic is commonly too fmall to be 
 difcoverable by any reddifh or orange caft, 
 till a part of the Sulphur has been exhaled 
 by fire or detained by additions. This ob- 
 fervation is to be particularly attended to in 
 perilling the writings of the ancient che- 
 
 mifts, who frequently direflt Sulphur to be 
 fublimed repeatedly from iron filings or 
 other matters, til! it becomes red and tranf- 
 parent like a ruby ; an effect in vain expe&ed 
 from the pure Sulphur we are now fupplied 
 with, but which readily fucceeds with the 
 arfenicated mineral forts which were then 
 made ufe of. 
 
 Z 2 
 
Mineral Salts. 
 
 Hoffman and others have prefumed, that Sulphur exifts in the air, and that 
 from this proceed thunder, lightning, and other fiery meteors; the vitriolic 
 Whether con. acid and j n fl am mable principle, the very ingredients from which art produces 
 fame in 1 e Sulphur, being unqueftionably diffufed through the atmofphere. Plaufible 
 as this theory may appear, it is liable to confiderable objections : Art cannot 
 produce Sulphur without a degree of fire, which we cannot fuppofe to have any 
 place in the atmofphere : No Sulphur can be generated but with the concen- 
 trated acid, and how infinitely, on the other hand, is the aereal acid divided 
 and diluted! Befides, the effects of Sulphur and of lightning are in nowife 
 fimilar. 
 
 air 
 
 V ITR I OLfi 
 
 General rela- 
 tion to metals. 
 
 Comparative 
 affinity to roe 
 tals. 
 
 Article II. 
 
 Combination oj the vitriolic acid with metallic bodies. 
 
 H E vitriolic acid, in its diluted fiate, and affifted by a moderate warmth, 
 very eafily diffolves Iron and Zinc ; the firft into a green, the other into 
 a colourlefs liquor. Copper is more difficultly aCted on: This metal requires 
 the ftrong undiluted acid or oil, and a heat fufficient to make it boil: The 
 more phlegmatic part of the liquor exhaling during the coCtion, fo much of 
 the acid remains united with the Copper, as to render it foluble in water : This 
 folution is of a fine blue colour. Silver, Quickfilver, Tin, Lead, and Re- 
 gains of Antimony, are likewife corroded by boiling in the concentrated acid, 
 but are not fo effectually diffolved by it as the three foregoing metals. Gold 
 is not aCted upon at all by the pure vitriolic acid however concentrated or 
 heated ; though when the acid is converted into Sulphur, and then combined 
 with fixed alcaline Salts into a Hepar, Gold is diffolved by this compound 
 equally with the other metals. 
 
 The vitriolic acid has a greater affinity with molt metals than any of the 
 other acids have. Thus, if added to a folution of Silver, for inftance, made 
 in the nitrous acid, it will attraCl the metal from that acid, and carry it to the 
 bottom. This rule does not obtain univerfaliy, but the exceptions are very 
 few : The principal exception is the ftrong affinity of the marine acid with the 
 metal above-mentioned •, this acid carrying down Silver from the vitriolic, as 
 readily as the vitriolic does from the nitrous (a). 
 
 The 
 
 [a) Affinities of the vitriolic acid with metal- 
 lic fubjlancest] The vitriolic acid, like the 
 others, has the greateft affinity, among me- 
 tallic bodies, with Zinc, which diflodges 
 from it all the others : The next, in degree 
 of attraction, are Nickel, Regulus of Co- 
 balt, and Iron ; next to thefe Copper ; and 
 after this, Quickfilver. Like other acids 
 alfo, on adding a volatile Alcali to the me- 
 tallic folutions, it depofites the metal, and 
 unites with the Alcali ; and this it will 
 again forfake for a fixed Alcali, 
 
 In fome circumftances, however, this acid 
 difcovers a greater attraction to metals than: 
 to fixt alcalies themfelves ; and in this re- 
 fpeCt it differs from all the other acids. If 
 fixed alcaline Salt faturated with the vitrio- 
 lic acid, (that is, vitriolated Tartar) be 
 added to a folution of Mercury or Silver ; 
 the acid inftantly forfakes the Alcali, unites 
 with the metal, difiodges it from its former 
 folvent, and carries it to the bottom. 
 
 Hence we are furnifhed with a folution of 
 the problem which Stahl fome time ago 
 
 propofed 
 
Mineral Salts. 173 
 
 The vitriolic acid difcovers in general a Itronger attraflion to the inflam-ViTRiOLs, 
 triable principle than to any other known fpecies of matter; and when com- ^ 
 
 bined with it, forms Sulphur. There are circumftances, however, in which ^ l 3 °]|“ t t !^ n c * 
 it forfakes that principle, to unite with fome metallic bodies, particularly Iron meta iii c f u b. 
 and Copper. If either of thefe metals be combined with Sulphur, and theihnces. 
 compound gently roafted or calcined, only the inflammable part of the Sul- 
 phur will be diffipated, its acid being retained by the metal, which is thus cor- 
 roded into a faline concrete, the fame as if the pure acid had been applied. The 
 fame change is producible, without the application of any external heat, from 
 a bare mixture of Iron filings and Sulphur moiftened with water: The matter 
 grows hot of itfelf, the Sulphur is relolved into its conftituent parts, its in- 
 flammable principle exhales, and its acid is detained by the Iron. From 
 molt of the other metals, Sulphur is expelled by fire in its whole fubflance. 
 
 A like refolution happens often fpontaneoufly in the mineral kingdom. p ro du£h’ors of 
 There are fundry minerals, which, examined in their natural ftate, appear to Vitriol, 
 confifi: of Iron and Copper, blended with Sulphur, and earthy or flony matters. 
 
 After they have been expofed for a time to the adtion of the air, we find no- 
 thing of the Sulphur left but the acid, by which the metal is now corroded 
 into a faline fubftance feparable from the indilfoluble matter by means of 
 water. 
 
 Combinations of metals with the vitriolic acid are called vitriols of thofe me- 
 tals. It is with manifeft impropriety that Boerhaave and others have extended 
 this name to metallic Salts made with other acids : For as one particular acid 
 is univerfally diftinguifhed by no other name than that of the acid of Vitriol, 
 it mult furely be productive of great confufion, to call thofe fubftances vitriols, 
 whofe acid is of a different kind. 
 
 VITRIOL. 
 
 THERE are Vitriols of three metallic bodies, produced fpontaneoufly, or Different forts 
 with little affiftance from art; thofe of Iron, of Copper, and of Zinc, of Vitriols, 
 The pure vitriol of Iron is of a grafs-green colour verging to blackifh ; that of 
 Copper, of a beautiful fapphire blue ; and that of Zinc white. The Vitriol of 
 one metal has frequently an admixture of that of another; and hence arifes a 
 fourth arrangement, of greenilh blue and bluifh-green, according as Iron or 
 Copper prevail in the compound ( b 
 
 Vitriols 
 
 propofed to the chemifts, <c to feparate the 
 “ vitriolic acid from fixed alcaline Salts, 
 *-<■ inftantly, and in the paim of the hand.” 
 Mr. Geoffroy has given a Memoir on this 
 problem ; in which he endeavours to re- 
 lolve it by changing the acid into Sulphur ; 
 namely by melting the vitriolated Alcali 
 with inflammable matters by a ftrong fire, 
 till the acid is combined with the phlogi- 
 ftoninto Sulphur, (See page 164.) then dif- 
 folving the compound in water, and preci- 
 pitating the Sulphur with acids : He thinks 
 
 it fufficient that this laft part of the procefs 
 be performed in the hand, though the repa- 
 ration of the acid was eiiedted in the fire. 
 
 (b) Vitriols .] Thefe Salts are remarkably 
 lighter than might be expected trom the 
 large quantity of metallic matter they con- 
 tain : Even when freed by fire from their 
 watery phlegm, they are lefs ponderous 
 than the Salts compofed of the fame acid and 
 fixed alcalies, in the proportion ol about 
 2 to 2 fev 
 
174. Mineral Sa'LTs. 
 
 v 
 
 Vitriols. Vitriols are prepared in Sweden, in feveral parts of Germany, &c. from the 
 ' — — yellow fulphureous Pyritae, whole metallic part is chiefly Iron ; and from feme 
 Method other minerals of the fame kind, impregnated with Copper. The firfl are of a 
 
 fhem. ri1ia pale yellow colour, and commonly approach to a cubical figure: The latter 
 
 are of a deeper greenifh yellow or Gold colour, and in figure more irregular. 
 Pyritgj. Both forts are compadl and hard, and difeover in their natural date no marks 
 of Vitriol, but yield Sulphur in abundance, Expofed to the atmofphere, 
 either entire or reduced into powder, they fuffer no perceptible change : But if 
 gently roafted or calcined, and then laid fora time in the air, they acquire a 
 ftrong vitriolic tafte, and readily give out to water the Vitriol now produced in 
 them. Thofe in which the quantity of Sulphur greatly prevails above that of 
 the metallic matter, are worked for Sulphur firfl: : After fo much of the Sul- 
 phur has been extradled, as can be commodioufly feparao-d by the common 
 proceflfes of fublimation or eliquation, enough is (till retained by the metal to 
 convert greateft part of it into Vitriol. 
 
 There are other kinds of Pyritae, very different in quality from the fore- 
 going. Thofe from which Vitriol of Iron is prepared in large quantity at 
 Deptford near London, and which are brought thither by water, chiefly from 
 Enjiifl-i Co- t h e Ifle of Wight, under the name of Copperas (tones, contain very little Sul- 
 peras Hones. ph ur? though on expofure to the air they become plentifully impregnated with 
 vitriolic acid •, and hold a (till fmaller portion of Iron, infomuch that it is ne- 
 ceffary to add frefb Iron to faturate the acid. Thefe (tones are confiderably 
 hard and compact, commonly of a roundifh figure, of a fparkling whitifti 
 grey colour, fometimes as large as the fi(t, and fometimes much fmaller. 
 They have no manner of tafte, and give out nothing to water by long boiling. 
 Diftilled in a retort, they yield a little fulphureous Sublimate, and a brownilh 
 or milky liquor of a ftrong fulphureous fmell : On the refiduum I made forty 
 different experiments with reductive fluxes, but obtained no appearance of any 
 metallic Regulus. The crude (tones, expofed entire to the air, lofe their 
 brightnefs, and change to a dull grey colour ; the fuperficial parts fcale off, 
 and become powdery ; and by degrees the whole (tone is converted into pow- 
 der, without the leaft afliftance from art. What was before Sulphur, is now 
 vitriolic acid : The powder has a ftrong, acid, ftyptic, vitriolic tafte ; and 
 yields, with the addition of Iron or Copper, a green or a blue Vitriol. The 
 ftones are found to differ in regard to the length of time neceflary for producing 
 thefe changes : Forfome, a few weeks are fufficient ; others require a twelve- 
 month; and others, as Boyle oblerves, a year and a half. 
 
 Thefe kinds of ftones are not peculiar to England. There are Pyritae in fe- 
 veral other countries, at Saalfeld, in Heflia, in Bohemia, about Liege, &c. 
 which yield Vitriol by a like treatment ; and require no calcination or other 
 Vitrlolefcent artificial operations, to render them vitriolic. The bituminous wood, found 
 wood. plentifully in the pits where Amber is dug, becomes alfo vitriolic by lying in 
 the air; and a very little air is fufficient for that effedt. I kept fome hard 
 compadt pieces of this wood, in a covered box, in a temperate place, forfome 
 years : They retained their figure, and ftill exhibited marks of the woody 
 fibres, but fell in powder on being touched, and appeared throughout vitrio- 
 lic : Some other pieces, kept for the lame length of time in a clofe ftopt glafs, 
 3 retained 
 
Mineral Salts. 173 
 
 retained a degree of firmnefs. Pyritae are likewife converted into a vitriolic Vitriols* 
 ftate in covered veffels, though more (lowly than in the open air. ' — — > 
 
 At the Vitriol works at Deptford, the ftones are fpread, to the depth of p reparation 
 about half a foot, upon an area of feveral hundred roods, whole bottom is of Copperas 
 compofed of clay, mixed perhaps with other fubftances, made (loping, and at Deptford, 
 beat folid and fmooth, fo as that water may run off. From the upper fide of 
 the grounds to the lower are dug fmall channels, at diftances of about ten 
 paces ; by which the vitriolic matter, wafhed out from the mineral by rains, 
 is carried down into wooden troughs placed tranfverfely at the lower fide. 
 
 Every two of thefe troughs empty themfelves into a wooden ciftern funk in 
 the ground betwixt them. From thefe the liquor is laded up with wooden 
 jets: If fufficiently ftrong, it is conveyed along a trough into the boiling 
 houfe : If too dilute, (rom immoderate rains or other caufes, it is returned, 
 by another canal properly difpofed for that purpofe, upon the ftones in the 
 upper part of the Vitriol ground. In great droughts, the deficiency of rain is 
 
 fupplied by artificial watering The vitriolic liquor is boiled down in large, 
 
 oblong, (hallow, leaden pans, with the addition of fuch old Iron as is pro- 
 curable at a cheap rate. When evaporated to a proper pitch for (hooting, it 
 is conveyed by troughs into long pits made in the earth, narrow at bottom, 
 and wider at top : In thefe, great part of the Vitriol cryftallizes ; after which, 
 the uncryftallized liquor is returned to the boilers with frefli vitriolic ley ; and 
 the procefs repeated till ftarce anything more will fhoot. This liquor is pur- 
 chafed by fome particular perfons, under the name of mother-ley : When the 
 workmen have large quantities, they return it upon fuch Pyrits as have not 
 been compleatly changed into a virriolefcent ftate- The cryftallized Vjtriol is 
 carried into the drying-houfe ■, and after fufficient exficcation, packed up in 
 cafks for fale. The work is carried on without intermiflion 5 the Vitriol 
 grounds being divided into a number of compartments, that one parcel of the 
 mineral may be ready to yield its acid, by the time that another is exhaufted. 
 
 Deptford is the only place where Vitriol is cryftallized in pits made in the Cryftallizati- 
 earth The cryftallization is commonly performed in large wooden tubs, on- 
 fitted with perforated covers •, a long ftick being thruft, through every hole of 
 the cover, to the bottom of the veffel, for the Vitriol to fhoot upon : The 
 fticks are frequently joined in pairs, by crofs pieces at the lower end, like 
 the Greek n. The cryftals are knocked off, dried a little, and put up in 
 cafks. 
 
 There are fundry waters naturally impregnated with Vitriol ; the greater num- vitriolic wa- 
 ber with that of Iron ; fome with that of Copper ; to which, in fome waters, theters. 
 
 Vitriol of Zinc is fuperadded. All the Chalybeate fprings, as thofe of Pyrmont, 
 receive their Virtues from a Vitriol of Iron, produced by a fpontaneous refolu- 
 tion of Pyritae. The vitriolic acid has a principal (hare in the impregnation of 
 all the mineral waters : Even thofe which contain an alcaline Salt, as the Carlf- 
 bade waters, feem to owe their Alcali to this very acid. This alcaline Salt dif- 
 fers in feveral refpe6Ls from vegetable alcalies, and appears to be the fame with 
 the bafis of Sea-fait : There is abundant reafon to believe, that it has been 
 actually taken from Sea-falt by the vitriolic acid ; and that this acid afterwards 
 forfookj and left it in the water, to unite with fomeching elfe, perhaps with 
 
 calcareous 
 
176 
 
 V ITRIOLS. 
 
 Mineral Salts. 
 
 calcareous earths ; for the vitriolic acid has a ftrong attraction to thefe earths, 
 and when combined with them, forms an infipid feienitic concrete, which we 
 find really to exile in waters (c). 
 
 In 
 
 (f) Impregnation of mineral waters.'] From 
 the foregoing fhort fketch of the impreg- 
 nation of mineral waters, our author ap- 
 pears to have had a more thorough know- 
 ledge of this fubje£t than any who has writ- 
 ten fmce. Mineral fpirits, unsupported by 
 experiment, have been called in aid to 
 account for the phaenomena; whilft the na- 
 tural affinities of the vitriolic acid, and its 
 obvious tranfpoutions from one body into 
 another, have been overlooked. The fol- 
 lowing experiments tend to confirm the 
 authors fuggeftions, and will probably give 
 fame further light into this affair. 
 
 1. If common Salt and Vitriol of Iron be 
 ■difiolved feparately in water, and then mix- 
 ed together ; the ferrugineous part of the 
 Vitriol will feparate and fall to the bottom, 
 •its acid uniting with the alcaline bafis of the 
 Sea-falt, and forming, with that, a new 
 compound, the cathartic Salt or Sal mirabile 
 of Glauber. 
 
 2. If, inftead of Sea-falt or its folution, 
 we take the earthy fubftance called Magnefia 
 &lba> or a folution of it in the vegetable, 
 nitrous or marine acids, a like refolution 
 happens, the acid of the Vitriol depofiting 
 its metallic bafis, and uniting with the 
 earth. The new faline compound, pro- 
 duced in this cafe, is the bitter cathartic Salt , 
 the fame with that obtained from the purg- 
 ing mineral waters, 
 
 3. On mixing a folution of Glauber’s Salt 
 with calcareous earths or folutions of them. 
 Lime-water for inftance ; the vitriolic acid 
 of the Glauber’s Salt forfakes its alcalne 
 bafis, and unites with the cabareous earth : 
 With this laft it forms a feienitic concrete, 
 very fparingly dilloluble in water, and 
 which, on ftanding, in greateft part fub- 
 iides, leaving in the liquor little other than 
 the difengaged alcaline Salt. It is needlefs 
 to mention, that if the quantity of Glau- 
 ber’s Salt is large, in proportion to that of 
 the calcareous earth, only a part of it will 
 thus be refolved. 
 
 4. On fubfiituting the bitter cathartic Salt 
 to Glauber’s Salt, the event is the fame ; 
 calcareous earths abforbing a part of the 
 
 acid of that Salt alfo, more or lefs in pro- 
 portion to their own quantity, and forming 
 with it a felenites: Only here, as the bafis 
 
 of the bitter purging Salt is an earth not dif- 
 foluble in wafer, this earth feparates and 
 fubfides, as foot! as it is deprived of its acid. 
 As the earthy matter, which remains upon 
 confifts partly of this earth, and partly of 
 Selenites, we may prefume, that a part of 
 the fait of the water was thus deftroyed in 
 the evaporation ; that a part of its acid was 
 transferred from one kind of earth into ano- 
 ther ; from an earth with which it forms a 
 bitter cathartic Salt, into one with which it 
 compofes a fubftance infipid to the tafte, 
 and of no purgative virtue. Hence we 
 learn, why the waters themfelves purge 
 more, than the Salt obtainable from an 
 equal quantity of them. 
 
 5. If equal quantities of green Vitriol 
 and the mineral alcaline Salt or bafis of Sea- 
 falt, be dropt into a ftrong bottle filled with 
 fpring-water, and the mouth inftantly clofed 
 fo as to leave no vacuity in the veil'd ; the 
 two Salts will be flowly difiolved, and lub- 
 fift quietly together fo long as the veflel is 
 kept clofely ftopt ; there being no room for 
 the extrication of the air, which all acids ex- 
 pel from alcalies in uniting with them, and 
 without the expulfion of which they cannot 
 unite with them. As foon as the bottle is 
 opened, the Salts begin to ad upon one 
 another, and the liquor exhibits the fame 
 remarkable phaenomena, as the natural 
 Chalybeate waters when brought up into 
 the open air: It fparkles or emits bubbles 
 bles of air, taftes brifle or fpirituous as it is 
 called, gives marks both of acidity and al- 
 calefcence, ftrikes with galls, not the black 
 which Vitriol does by itfelf, but a fine 
 purple : On ftanding for a little time, it 
 lofes thefe qualities ; the Vitriol is deftroy- 
 ed ; its Iron falls to the bottom in form of 
 Ochre, its acid being abforbed by the Al- 
 cali. The remaining liquor, evaporated, 
 leaves only a little cathartic Salt, and a part 
 of the Alcali unneutralized ; together with a 
 portion of marine Salt and different earths 
 which the Ipring-water contained before. 
 
 This 
 
Mineral Salts. 177 
 
 In many places we meet with cryftals of Vitriol fpontaneoufty formed in the Vitriols. 
 earth, as at Rammelfberg near Goflar, in Hungary, &c. Thefe alio appear' — 
 to receive their origin from Pyritse. At Rammelfoerg there is abundance Vl ~ 
 
 fulphureous Pyrirse, both cupreous and ferrugineous : Twenty-five or twenty- 
 fix hundred weight of Sulphur are prepared there every week ; and about 
 eighty hundred weight of Vitriol. As at this place there is plenty of the in- 
 gredients for the produfiion of Vitriol ; fo neither are the means wanting for 
 its being produced in the mine itfelf. There is heat fufficient, from the wood 
 fires made for burflingthe hard makes of ore, for gunpowder is never employed 
 for that purpofe here : A whole flack of wood is fet on fire at a time, by which 
 the mine is made fo hot, that the men are obliged to work naked. Water, as 
 in all mines, is but too plentiful ; and all the Rammelfberg waters are frrongly 
 impregnated with Vitriol : A drop, falling on the clothes, leaves at firlt a 
 flain, and in no long time makes a hole. It is little wonder, that in fuch a 
 place vitriolic cryflals fhould be formed. In fundry caverns of the mine, 
 above, below, hanging from the top and fhooting up from the bottom, we 
 find icicles of Vitriol, of various fizes, fome as thick as the arm, curicufly 
 cluflered together, like garden-beds or grotto-work, white, reddifh, flefh 
 coloured, green, bluifh green, of a pure blue; affording, efpecially when 
 viewed by candles, a moft beautiful fpedlacle. 
 
 At this place, the white Vitriol is prepared ; from a mixt ore, containing Preparationof 
 Sulphur, Zinc, Calamine, Copper, Iron, Lead, and other metallic fubftances. vv f lite Vi ~ 
 The ore is roafled, and elixated with frefh parcels of water; the liquor fet by tno1, 
 to fettle, then boiled down in leaden pans, and cryflallized. If the cryftals 
 have any reddifh tinge, which they commonly have, they are again calcined, 
 diflblved in water, the folution purified by fettling, evaporated till it becomes 
 thick, and then poured into moulds : This procefs is repeated till the matter 
 becomes fufficiently white. As there is little confumption for this kind of Vi- 
 triol, it is made but feldom ; fometimes fcarcely once in fix or feven years. 
 
 The ore remaining after the extradlion of the Vitriol, is fmelted as frefh ore. 
 
 The white Vitriol has hitherto been prepared at Rammelfberg only : It is faid 
 that a little begins now to be produced in Hungary. 
 
 The vitriolic acid has a greater affinity with Iron than it has with Copper. Converfion of 
 If vitriol of Copper be diflblved in water, and fome clean Iron added to the one kind of 
 folution, the acid will let the Copper fall, and take up a proportionable quan- ^ ri ° I _ into 
 tity of the Iron : The blue colour of the liquor is now changed to a green ; and aa 
 on evaporating and fetting it to fhoot, we obtain, inftead of the blue vitriol of 
 Copper, a green one of Iron. The Copper in this experiment is extricated 
 from the acid in its metallic form, and adheres all over the furface of the Iron : 
 
 If the Iron is in thin pieces, and its quantity duly proportioned to that of the 
 acid, nearly the whole of the Iron will be extracted, and a mafs of Copper 
 of the fame figure left in its place. Hence arofe the ancient conceit, of Iron 
 
 being 
 
 This experiment may give, perhaps, no lofe their peculiar qualities, and depofite 
 unjuft idea of the natural impregnation of their ferrugineous ingredient, on being 
 Chalybeate waters in the bowels of the brought into a ftate of left confinement, 
 earth ; and of the manner in which they 
 
 A a 
 
1 7 8 
 
 VjTRJOLS. 
 
 Adhesion of 
 t'ie acid in 
 different Vi- 
 triols. 
 
 Gold not con- 
 tained in Vi- 
 triols. 
 
 Mineral Salts. 
 
 being tranfmuted into Copper by the waters of Neufol in Hungary ; which 
 waters are no other than a natural folution of venereal Vitriol. The Copper 
 thus obtained from them is very pure and high coloured : It is commonly 
 
 called Cement -Copper , but might be named with greater propriety, precipitated 
 
 Copper. 
 
 Blue Vitriol may in like manner be converted into white, by the addition of 
 Zinc; that femi metal precipitating the Copper as readily as Iron does. It has 
 been laid, that Zinc precipitates Iron alfo from the vitriolic acid, and that 
 green Vitriol may thus be converted into white. But on trial it did not ap- 
 pear that Zinc precipitated any more of the Iron than would have fallen fpon- 
 taneoufiy-, the ferrugineous folution, after digeftion both with Zinc and with 
 its ore Calamine, yielding flill not white but greenifh cryftals 
 
 It is obfervabie that the adhefion of the acid with the feveral metals is not 
 in proportion to its degree of affinity or appetite of union with them, but the 
 very revet fe. Though it readily and totally forlakes Copper upon prefenting 
 to it Iron or Zinc, it is neverthelefs far more difficultly difunited by fire from 
 the former than from either of the latter: It is expelled from Zinc the molt 
 eafily of the time. 
 
 There is rarely or never any metallic body befides thefe in the compofition 
 of Vitriols ; though fome have imagined that thefe Salts are im pregnated with 
 Gold. There are indeed inftances of a little Gold having fometimes been ex- 
 tracted from them : But the Gold thus obtained was by no means an ingre- 
 
 dient in the Vitriol as fuch ; and had only been cafually embedded in the mafs, 
 as it is in different ftony and earthy matters in the Gold mines. Thofe who 
 have been deluded into the molt fanguine expectations by experiments on a 
 fingle fpecimen, have been convinced of this truth upon fubmitting another 
 parcel to the fame trials. 
 
 The alchemifts have expedited to find in Vitriol no lefs than an univerfal me- 
 dicine, and the philofophers-ftone. With them the metallic part of the Vi- 
 triol precipitated by fixt alcaline Salts, has been efteemed a folar Sulphur, and 
 celebrated as an anodyne of extraordinary virtue. They have treated, by a 
 variety of operations, the cry ftallized Vitriol itfelf, the liquor which remains 
 after its cryftallization, the rainbow-coloured cuticle which forms upon folu- 
 tions of it ; but have always been difappointed in their aim. The following 
 fentence, whole initial letters compofe the word Vitriolum , has animated them 
 in the purfuit ; Vifita interior a terra , reperies ibi occult urn lapidem, veram medi- 
 einam ; that is, “ Vifit the inner parts of the earth, and there you (hall find 
 “ the hidden ftone, the true medicine.” Another fentence, whofe initials in 
 like manner make up the word Vitriolum , is much more juft; Via ijla tbefauros 
 requirendo inutilem operant Infer unt viri multi ; “ Many have fearched for trea- 
 “ fures in that way, and bellowed their labour in vain.” 
 
 I. V I- 
 
J 
 
 l 19 
 
 Mineral Salts, 
 
 I. VITRIOL of IRON. 
 
 If IT R I O L. of Iron difiolves in about twice its weight of water, into a green Vitr rot, 
 liquor; and on duly evaporating the folution, and fetting it to fhoot, con- OF j RON 
 cretes again into thick rhomboidal cry lTrals : If the crystallization is performed « _ _ _ _ » 
 
 in a warm place, the Vitriol commonly rifes up above the liquor, and con- General pro- 
 
 cretes into efflorefcences about the edges 
 
 of the veffel. It retains in its cry- pities. 
 
 ftalline form a large quantity of water, amounting to full as much as the 
 metal and acid together. In a warm dry air it lofes a part of its water, and 
 falls by degrees into a white powder. 
 
 On diffolving the powder or the cryftals in water, a portion of the Iron ischanges pro- 
 left undiffolved at the bottom of the veffel (d), in form of a reddifh yellow or duced by re- 
 rufty- coloured calx or ochre: The exficcated powder leaves confiderably moreP eated 
 of this ochre than the cryftals. The folution depofites, on {landing, more 0 " 0 ' 
 and more of the metal in the fame form ; and being now evaporated yields 
 cryftals paler coloured than at firft, with an unduous liquor, which refufes to 
 cryftallize, and which on further evaporation forms a butyraceous mafs that 
 deliquiates in the air. How often foever the folution and cryftallizarion are 
 repeated, a part of the Iron remains always undiffolved, apart feparates fpon- 
 taneoufly from the folution, and a part is reduced into a butyraceous matter; 
 the cryftals being paler and paler till the whole quantity is thus deftroyed or 
 refolved. The further the cryftals are freed from their metal the more eafily 
 do they part both with their water and their acid. 
 
 The cryftals, expofed to a gentle fire, liquefy and boil up : and having gra- £ff e ^ s 0 p £ re> 
 dually difcharged the greateft part of their water become confident again, 
 with the lofs of their tranfparency and green colour. The mafs, when it firft 
 becomes folid, appears of a whitifh colour : On urging it with a ftronger fire, 
 acid fumes fucceed the watery ones, the matter becomes yellow, red, and at 
 length of a deep purplifti red. 
 
 It is from this kind of Vitriol, as being the cheapeft, that the vitriolic acid Calcination 
 has been generally extraded for common ufes. The Vitriol is firft calcined of Vitriol, 
 uiuaily in Iron pots till it will no longer melt, as its melting in the diftilling 
 veffel would endanger burfting it : The calcination is advantageoully continued 
 alfo beyond this period, as more of the phlegm is thus diftipated without 
 much lofs of the acid. On colluding the vapours they are found to have 
 very little acidity till the Vitriol has become yellow : From this ftate to that of 
 
 rednefs. 
 
 (. cl ) Spontaneous feparation of the Iron from 
 Vitriol.] A folution of the Vitriol in water 
 depofites, upon {landing, a part of its me- 
 tallic bafis : In length of time, nearly the 
 whole quantity fubfides, leaving the liquor 
 colourlefs. The precipitation is greatly ex- 
 pedited by a boiling heat ; by which more 
 of the metal feparates in a few minutes 
 than by {landing without heat for a twelve- 
 
 month. Upon expofing the folid Vitriol to 
 a moift air, a fimilar refolution happens on 
 its furface ; which, in a {horter or longer 
 time, according as the Vitriol is more or 
 lefs faturated with metal, changes its green 
 to an ochery or rufly hue. Iron does not 
 leparate in this manner from any other acid, 
 nor any other metal from this acid. 
 
 A a 2 
 
i So Mineral Salts. 
 
 Vitriols, rednefs, they prove considerably acid : All that arifes after the matter has be- 
 come red, is a ftrong concentrated acid. 
 
 The diftillation is performed in earthen longnecks placed in a reverberatory 
 furnace : The makers of Oil of Vitriol in England put fifty ormoreof thefe veffels 
 in one furnace. To each long-neck is luted aglafs receiver; which, if the Vitriol 
 has been fully calcined, need not be large : The neck of the diftilling vefftl is 
 introduced into the belly of the receiver, left the drops falling on the neck 
 of the glafs (bould crack it. The fire is raifed by degrees, and continued for a 
 certain fpace of time, ufually fome days and nights; beyond which, expe- 
 rience has taught the workmen that the produce of acid would not pay the 
 expence of fuel ; care mu ft be taken, in Supplying frefti fuel, not to crack the 
 •veffels by admitting cold air to them : A volatile fuffocating fmell, like that of 
 burning Sulphur, gives notice of fuch an accident. If the veffels will bear a 
 good fire towards the end of the diftillation, we commonly obtain an highly 
 concentrated acid, in a thick butyraceous form, called glacial Oil of Vitriol: 
 In fuch cafe we muff be well upon our guard in taking off the receiver; this 
 concentrated acid, as foon as any communication with the air is opened, emit- 
 ting, in great abundance, fubtile penetrating fumes capable of linking a man 
 dead. 
 
 Oil of Vitriol, asfirft diftilled, appears of a brown or blackifh colour, which 
 fome aferibe to a portion of Iron or Copper brought over with it in the diftilla- 
 tion. But neither of thefe metals give any fuch tindlure to this acid : Inflam- 
 mable fubfiances do. A fmall bit of white paper will change the cleared: Oil of 
 Reflification. Vitriol, in a little time, quite black: The acid thus tindlured, and that which 
 arifes coloured from the Vitriol, are both rendered clear by the fame means, 
 barely by being heated. The phlegmatic acid is rectified by diftillation in a 
 glafs retort; the weaker acid or Spirit of Vitriol diftilling, whilft the ftronger 
 called Oil remains behind. In this procefs the retort fhould be placed, not in 
 fand as fome direbt, but in capella vacua or an empty Iron pot, with only a 
 little fand ftrewed on the bottom to keep the retort fteady: When the glafs is 
 buried in fand it is very unequally heated, and hence very liable to crack. 
 Analysis of One hundred pounds of Englifh Vitriol, calcined to yellownefs, were re- 
 different Vi- duced to fifty-five pounds, which yielded fifteen pounds of concentrated oil. 
 triols. From a more exadl examination it appeared, that Sixteen ounces of this kind 
 
 of Vitriol contain above eight of water, one and a half of pure acid, and about 
 fix of Iron ; with a fmall proportion of Alum, too fmall to be of any import- 
 ance. The aluminous matter is moft diftinguilhable in the crude liquor of the 
 pyrites, before it has been made into Vitriol ; and in this we may difeover alfo 
 fome marks of marine acid : The Vitriol itfelf very rarely participates of that 
 acid in any degree. 
 
 The Englilh Vitriol is purely ferrugineous ; but there is Scarcely any other 
 Vitriol of Iron without fome admixture of Copper. The Gofiarian, Hunga- 
 rian, Bohemian, Saxon, Ruffian, Roman, Saltzburg, French, and Swedifh, 
 are all mixed Vitriols ; and in proportion as they abound with Copper con- 
 tain lefs water and more acid than the pure Vitriol of Iron. Sixteen ounces 
 ofGofiarian Vitriol (the fort commonly made ule of in Germany) were found 
 to contain Seven ounces of water, three ounces of acid, five ounces Seven 
 
 drams 
 
 Oil of Vi- 
 triol. 
 
 It;s colour 
 whence. 
 
Mineral Salts. 181 
 
 drams and one fcruple of Iron, and nearly two fcruples of Copper : In the Vitriols. 
 fame quantity of another parcel, the water amounted to feven ounces and fix <— -v— —J 
 drams, the acid only to two ounces and two drams, and the metallic matter to 
 fix ounces : A third parcel yielded lefs water and more acid. Thele diffe- 
 rences depend chiefly upon the age and drynefs of the Vitriol, a part of the 
 water being difil paced in keeping. 
 
 The Vitriols which participate of Copper readily difcover that metal upon 
 rubbing them on a moiftened bright piece of Iron, which they inftantly cover 
 with a cupreous coat. It Items as if the metallic part of all Vitriols had been 
 formerly fuppofed to be Copper only : Hence even the ferrugineous Vitriols 
 
 have, in different languages, received names exprelfive of Copper ; by the Eng- 
 lish they are called copperas ; by the Germans, kitpfferw offer ; by fome of the 
 Latin writers cuperofum (i. e. cuprum erofum ;) by the Greeks yooXnoiv^^ 3 . 
 
 Green Vitriol ftrikes a black colour with vegetable aftringents ; and hence Ufe in dying, 
 is the bafis of the black dye for cloth, leather, hats, &c. The workmen 
 find that the mixed Vitriols anfw.er better for thefe purpofes than the purely 
 ferrugineous ; probably from the cupreous part of the Vitriol being more cor- 
 rofive, more effectually penetrating the iubjedt, and thus occafioning the co- 
 louring matter to fink deeper: The Copper certainly does not contribute to the 
 colour itfelf, for neither the Vitriol of Copper, nor Verdegris, ftrike any black- 
 nefs with aftringents. The manufacturers of tobacco are laid to make ufe of 
 this Salt for deepening the colour of that commodity. Common ink is pre- 
 pared from Vitriol and Galls : Bromel tells us that the belt ink is made accord- 
 ing to the old monadic verfe, Uncia fit galU, femifque fit uncia gummi, Vitrioli 
 pars quart a ; his addas odio falerni : But the liquor thus prepared will not long 
 keep, eipecially in an open veffel. To make a black and durable ink, I digelt Ink * 
 fixteen ounces of bruifed Galls in two quarts of French white wine for feveral 
 days; and then pouring off the wine, gently boil the Galls in two quarts of 
 water : Six ounces of Goflarian Vitriol are diflbived in this decoCtion, the wine 
 added to the folution, the mixture digefted for fome hours, eight ounces of 
 Gum Arabic put in, and when this is diflfolved, a dozen or more of entire 
 Cloves, which in good meafure prevent rriouldinefs. Some add Sugar, others 
 Salt, and others Spirit of Wine, to keep the ink froth freezing in winter. 
 
 From thefe ufes of the Chalybeate, which is the mod common of the Vitriols, 
 all the forts have been called atramenta ; and minerals impregnated with them 
 lapides atr ament arii , atr ament jiein. 
 
 Vitriol mixed with Nitre or Sea-falt, and expofed to the fire, extricates the 
 acids of thofe Salts; the vitriolic firft parting with its own acid which thus 
 diflodges the others in the fame manner as if Oil of Vitriol had been taken. 
 
 Hence the ufe of Vitriol in the diftillation of Aqua fortis. The mixed Vitriols 
 are faid to anfwer better for this purpofe likewife than the pure Vitriol of Iron : 
 
 The Englifh themfelves frequently employ foreign Vitriols in preference to 
 their own («•). 
 
 The- 
 
 (?) Mechanic ufes of Vitriol. ] In the Swedifh made into a pafte with water, is to be di* 
 Tranfadtions, Vitriol is recommended as luted with a folution of Vitriol, more or lefs 
 a. yellow for houfe-painting : Quicklime, according as the colour is required deeper 
 
 or; 
 
i 8 2 Mineral Salts. 
 
 Vitriols. The medical effects of Vitriol are fimilar to thofe of the other preparations 
 <— — ■ -v— of Iron. The pure Vitriol of Iron is here alone to be ufed : The mixed forts 
 Medical ides. ma y be rendered purely ferrugineous, by diffolving them in water, and adding 
 fome bright Iron, which will totally precipitate the Copper; after which the 
 Vitriol is to be recovered by cryftallization. It is obfervable, that in fmoking 
 tobacco, a little Vitriol taken into the mouth, leaves, after its aftringency is 
 over, an agreeable fweetnefs — —Externally, this Salt is employed as a ftyptic, 
 either diffolved in liquors or calcined. The ftypticum heroicum , as it is called, 
 is compofed of a pound of Hungarian Vitriol and half a pound of Alum dif- 
 folved in three pounds of phlegm of Vitriol, and mixed, after filtration, with 
 five ounces of Oil of Vitriol. Vitriol calcined to whitenels, by the fun’s heat 
 in the dog-days, has been celebrated for ridiculous fympathetic virtues : Sir 
 Kenelm Digby and others have been fuperftitious enough to believe, that it 
 would cure wounds by being applied only to the weapon they were made with, 
 reftrain haemorrhages by the blood being dropt upon it, and produce various 
 effects in the body by being put into the patient’s urine, &c. 
 
 II. VITRIOL of COPPER. 
 
 Vitriol Vitriol of Copper contains much lefs water than that of Iron, and re- 
 
 v quires a larger quantity, about four times its own weight, for its lolution. 
 
 t oppeR ’ ^ does not, like the green Vitriol, part with any of its metal on being dif- 
 k offire ^ ve< ^ ’ nor calcine in the air, or liquefy in the fire. Expofed to a gentle heat 
 s it fir ft turns white, and then of a yellowifh red colour: On urging it with a 
 ftronger fire the acid flowly exhales, and a dark red calx of Copper remains, 
 of a much lefs lively colour, and inclining more to a brown, than the calx 
 prepared in the fame manner from the Vitriol of Iron. The whole of the acid 
 cannot be feparated by diftillation from either fort •, fo much acid remaining 
 united with the metal after that operation as to render a part of it foluble in 
 water : After this foluble part has been extracted, a little acid is ftiil retained, 
 amounting to about one twenty-fourth part of the metallic calx. 
 
 Vitriol of Copper is commonly called Cyprian, probably from its having 
 been formerly brought from the ifiand Cyprus in the Elgtean lea. Boerhaave 
 makes the Cyprian and Hungarian Vitriols the fame , but they differ greatly 
 
 from 
 
 or lighter : The mixture appears of abluifh 
 green colour, and does not become yellow 
 till it is dry. One part of Vitriol is laid to 
 go as far as two of the dearer yellow Ochre. 
 
 This Salt is recommended alfo for pre- 
 ferving wood, as particularly the wheels of 
 carriages, from decay : When all the pieces 
 are fit for being joined together, they are 
 diredted to be boiled in a folution of Vitriol 
 for three or four hours, and then kept for 
 fome days in a warm place to dry. It is 
 faid that wood by this preparation be- 
 comes fo hard and compadt that moifture 
 
 cannot penetrate it ; and that Iron nails are 
 not fo apt to be deftroyed by ruft in this vi- 
 triolated wood as might be expedted, but 
 laft as long as the wood itfelf. 
 
 There are fome inftances fufficiently at- 
 tefted of human carcafles being preferred 
 for a number of years, in vitriolic mines, 
 free from corruption. In a hiltory of this 
 kind related in the literary adds of Sweden, 
 all the natural features remained unaltered, 
 though the body had lain forty-nine years : 
 The flefh was grown of a horny hardnefs. 
 
Mineral Sal t s, 183 
 
 from one another, the former being a pure Vitriol of Copper, the latter a mixt Vitriols. 
 Vitriol of Iron and Copper. ^ 
 
 Vitriol of Copper is never produced by nature without an admixture of Iron. Preparation. 
 The pure venereal Vitriol is made by art, from cuttings or wade pieces of 
 Copper, ftratifled and cemented with Sulphur: The cover of the cementing- 
 
 pot is perforated with one or two fmall holes, and the cementation continued/ 
 with a gentle fire till the inflammable part of the Sulphur is confumed : The 
 
 matter is then boiled in water, and the liquor, after due evaporation, fet to 
 fhoot. Such part of the Copper as remains uncorroded, is treated with frefli 
 Sulphur, til! the whole of the metal is changed partly into Vitriol, and partly 
 into an indifloluble calx. For the inferior kinds of this Vitriol, Pyritas abound- 
 ing with Sulphur are fubftituted to pure Sulphur. There are few places in 
 which Vitriol of Copper is prepared, the conlumption of this commodity not 
 being very confiderable. 
 
 Vitriol of Copper has been recommended in all kinds of intermittent fevers, Medical ufes. 
 in the lepra, and when faturated with volatile alcaline fpirits, as a fpecific in 
 epiiepfies. In this lad cafe I have known it given with very ill fuccefs, the 
 convulflons being made by it far more violent. Its internal ufe is in no cafe 
 to be ventured on, as it poflefles a truly deleterious quality, in common with 
 the other preparations of Copper: The fmalleft portion occafions a ficknefs and 
 naufea-, a fomewhat larger, Teachings and violent vomitings, accompanied 
 often with convulflons : If the quantity taken has been confiderable, and is not 
 foon dilcharged by the vomiting, the ftomach and inteftines are corroded, in- 
 
 tenfe pains, inflammations, and death fucceed- Externally, it is tiled as a 
 
 mild efcharotic, in fhankers, and for confirming proud flefh : and for redrain- 
 ing haemorrhages. It is applied by the farriers againft films on the eyes of 
 cattle. 
 
 III. WHITE VITRIOL, 
 
 H ER E have been many different, and for the mod part erroneous, con- White 
 jebtures about the nature aud compofuion of this kind of Vitriol. Boer- Vitriol. 
 haave fuppofes it to be no other than Vitriol of Iron exficcated fo as to be- > __ j — > 
 
 come white. Geoffroy comes nearer the truth, in faying it confids of vitrio- 
 lic acid united with Calamine, or with a ferrugineous earth and Lead or Tin. 
 
 Tin however mud be excluded from the compofuion, as nothing of that me- 
 tal is difcoverable either in the Vitriol itfelf, or in the ores from which it is 
 prepared. 
 
 Experiment drew?, that the metallic part of v/hite Vitriol is principally Analysis, 
 Zinc: When freed from its acid by drong fire it tinges Copper yellow, or 
 changes it into a kind of Brafs, the didinguifhing character of that femimetak 
 It participates alfo of the Iron and Copper, and perhaps of the Lead, 'with which 
 the ores abound. That it contains Iron appears from the ochery fediment 
 which dilutions of it depofite on danding ; and dill more evidently, from its 
 yielding, when treated with inflammable fluxes, particles of true Iron to the 
 magnet. Rubbed on a poliflied moifl knife, it dains the Iron of a Copper 
 colour: Zinc, added to iohmons of it, throws down a Precipitate, which 
 5 B’ ves 
 
184 Mineral Salts. 
 
 Vitriol, gives a deep blue tinfture to Spirit of Sal ammoniac; plain proofs of its holding 
 U— Copper. 
 
 White Vitriol diffolves as eafily as the green, in twice its weight of water. 
 It does not calcine or fall into powder in the air, nor liquefy in the fire. In 
 diftillation, four ounces yielded about an ounce of phlegmatic fpirit, nearly 
 three ounces remaining in the retort : The fpirit, examined by alcaline Salts, 
 was found to contain only half a fcruple of pure add to feven drams and fifty 
 grains of water. If the fire had been continued for fome days longer, more 
 acid would probably have been obtained. 
 
 Medical ufes. White Vitriol was given formerly as an emetic, from a fcruple to half a 
 dram, two fcruples, and fometimes a whole dram; either in its common Hate 
 as brought into the fhops, or purified by folution and cryftallization, when it 
 is called gilla theophrajli. At prefent its ufe in that intention is almoft entirely 
 laid afide: and indeed it may very well be fpared as an emetic; two or three 
 grains of emetic Tartar, or a little wine impregnated with glafs of Antimony, 
 operating as effedtually as a dram of white Vitriol, and with much lefs fickneis 
 or uneafinefs to the patient. Some report, that both the white and blue Vi- 
 triols occafion a falivation : This is by no means to be underftood as a faliva- 
 tion fimilar to that brought on by mercurials, and is no other than a difcharge 
 of phlegm or water from the naufea which they excite. White Vitriol is in 
 common ufe externally, in ointments and collyria, againft heat, inflammati- 
 ons and defiuxions of the eyes : Sometimes a little Sugar of Lead is added. It 
 is one of the beft applications for thefe purpofes, and I have known it a very 
 lucrative fecret in particular hands. It is likewife a powerful and fafe errhine, 
 of good ufe in catarrhs, and obftrudlions of the noftrils by indurated mucus : 
 A folution of the Vitriol in Marjoram water is to be fnuffed up the nofe, or a 
 bit of cloth dipped in it occafionally introduced. Confiderable quantities are 
 ufed by the farriers, and thole who prepare varnilhes : It is laid to promote the 
 drying of varnilhes and oil paints. 
 
 Article III. 
 
 Combination of the vitriolic acid with earths . 
 
 Experiments H E Vitriolic acid readily and totally diffolves the afbes of vegetables into 
 on calcareous j[_ a limpid liquor. Calcareous earths are corroded but not diffolved by it: 
 earths and vi- With thefe it forms a felenitic matter, in appearance refembling a Salt, but 
 tnohc aci . differing f rom bodies of that clafs in wanting tafte and folubility. When the 
 earth is previoufly diffolved in water it forms with the vitriolic acid a like con- 
 crete, which refufes to diffolve again : Three quarts of Lime-water were fatu- 
 rated by fix drams of Spirit of Vitriol, of moderate {Length ; and being then 
 evaporated left near two drams of this matter in little maffes like fine flowers 
 of Benzoine. Half an ounce of green Vitriol, diffolved in water, required for 
 its faturation eight pounds and four ounces of Lime-water : The metallic calx, 
 precipitated by the earth of the Lime-water, weighed one dram, and eighteen 
 grains: The liquor filtered and evaporated, left only a dram and a half of a 
 
 whitilh fomewhat fparkling concrete. To fixteen ounces of Quick-lime in 
 
 lubftance. 
 
Mineral Sa.lts. 185 
 
 fubftance, put into water enough to flake it and well ftirred together, I added A lijm. 
 by degrees Goflarian Vitriol till the Lime was faturated, and a frefli addition 
 occafioned no further effervefcence ; three pounds and a half were requifite for 
 thispurpofe: The matter being now elixated with water, and the liquor eva- 
 
 porated, only one ounce three drams and ten grains were found to have been 
 taken up by the water: The undiflolved part weighed when dry, three pounds 
 and nine ounces. The part which the water had diflolved at firft would not 
 any longer diflolve after it had once been feparated. - 
 
 There is another kind of earth, which the vitriolic acid diflblves with eafe ; Aluminous 
 and with which it concretes into an aftringent Salt readily foluble in water, earth, 
 called Alum. This earth is commonly laid to be chalky; but I have treated 
 Chalk, Lime, Boles, Lac lunse, and various other earths with Spirit of Vi- 
 triol, without being ever able to produce any Alum. What this earth really 
 is, remains as yet unknown. It does not feem to exift naturally in the ores 
 from which Alum is prepared, in the fame ftate wherein it enters the compofi- 
 tion of Alum; but to receive its peculiar properties from the calcination and 
 expofure to the air neceflary for the produition of that Salt. In the feveral 
 Alum-ores which I have had an opportunity of examining, there was no mark 
 of fuch an earth as we obtain from Alum (/). 
 
 I. A L U M. 
 
 J^ATURE produces no perfeft Alum, but affords the materials for it in Natural hlf- 
 fundry ores, pyritte, Hones, flates, earths, waters, and bitumens as pit- tory of Alum 
 coal. The reddifh Roman Alum is prepared from a reddifh ftone found at the 
 bottom of the hill Tolfa near Civita Vecchia in the ecclefiaftical ftate : In Swe- 
 den and fome parts of Bohemia Alum is made from Pyritae and other ores ; in 
 England, at Altfattel and fundry other places, from bituminous minerals of 
 the pitcoal kind ; at Solfatara near Naples, from a whitifh earth; in Mifnia, 
 from a blackifli one ; at Leowenberg near Freyenwalde, from a reddifh one ; 
 
 and 
 
 (f) Earth of Alum. ] Some later experi- 
 ments, by Mr. GeofFroy and Mr. Pott, have 
 fhewn, that the earth of Alum is contained 
 in clay, and that a true Alum may be pre- 
 pared by digefting clay in the vitriolic acid. 
 Both thefe gentlemen imagine, that only a 
 particular part of the clay is here extracted : 
 Whether it exifted originally in the clay, 
 poffefled of the fame properties which it is 
 found to have when extracted, or whether it 
 has fuffered a change in the operation, they 
 have not determined. Prom the experi- 
 ments I have made, the latter feems to be 
 the cafe. Powdered tobacco-pipe clay be- 
 ing boiled in a confiderable quantity of Oil 
 of Vitriol, and the fire continued to dry- 
 nefs, the matter, examined when grown 
 cold, difcovers fcarcely any tafte, or only 
 
 a flight acidulous one : On expofure to the 
 air for a few days, greateft part of it is 
 found changed into lanuginous efflorefcences 
 in tafte exaftly like Alum: The remainder, 
 treated with frefh Oil of Vitriol in the fame 
 manner, exhibits the fame phasnomena, 
 and this repeatedly till nearly the whole of 
 the clay is converted into an aftrin- 
 gent Salt- — —If the earth be feparated again 
 from the acid, (by diflolving the Salt in 
 water, and precipitating with any alcaline 
 Salt) it is now found to difFolve with eafe 
 in every acid ; to form with the vitriolic 
 Alum again; with the nitrous, a compound 
 refembling Alum in tafte ; with the vege- 
 table acids, a fubftance lei's aftringent,- and 
 lefs ungrateful, 
 
 b 
 
1 86 Mineral Salts. 
 
 Alum, and from different minerals at Saalfeld, Reichenbach, Leuferfdorff, Suferf- 
 v — —v— — ' dorflf, Eliard, Schwentzel, Duben, &c. There are waters impregnated with 
 Alum, though I have never feen any that left a perfetft Alum on bare eva- 
 poration. 
 
 The pureft and moft perfect Alum-ore is the reddifh ftone of Tolfa : This is 
 faid to yield Alum without any additional matter, though not without artifi- 
 cial managements : The Alum obtained from it is tindhired with the reddifh 
 colour of the ftone. In its natural (late it gives no marks of Alum ; and if 
 cxpofed to the air, it continues a hard infipid ftone. Calcined or roafted, and 
 then laid for a time in the air, it becomes by degrees aluminous, and gives out 
 its Alum on being boiled in water. This is the Alum which the Italians call 
 Alume di rocca , Alum made from a ftone or rock: Among us, the name Alu- 
 men rupeum or rock Alum is often applied to the larger cryftalline maffes, what- 
 ever fubjedt they have been prepared from. 
 
 The aluminous Pyritas and bitumens require no calcination unlefs they greatly 
 abound with Sulphur. Thefe minerals, as firft taken out of the earth, are 
 compact, and often bright and glittering : They have no manner of tafte, and 
 difcover no mark of their holding any thing faline ; the vitriolic acid being as 
 yet blended v/ith an inflammable matter, by which its acidity and all its faline 
 characters are deftroyed. On bare expofure to the open air, the inflammable 
 principle is diflipated, and the acid is combined With the aluminous earth into 
 a perfeCt Alum, the ftone at the fame time falling into powder. 
 
 Preparation. The mineral thus impregnated with Alum, is elixated or boiled with water j 
 the liquor boiled down, commonly with an addition of urine, or alcaline ley, 
 or both together-, the clear part poured off and fet to fhoot; the cryftals, if 
 riot diffidently pure, diffolved again, boiled down with a little more A lcali, 
 and cryftallized afrelh. The ufe of the urine or alcaline Salt is partly to cla- 
 rify the liquor and precipitate fuch metallic parts as it may contain ; and partly 
 to give a body to the Alum, and promote the cryftallization : The liquor of 
 itfelf would not fhoot, but either continue fluid, or if further evaporated, 
 would yield only anunCluous mafs. Alcaline Salts are found to anfwer better 
 than urine, and hence are now in moft places alone made ufe of, though- fome 
 ftill retain urine, from prejudice and cuftom. The Alcali precipitates not 
 only metallic matters, but a grofs earth which would injure the tranfparency of 
 the Salt; and often alfo a part of the aluminous earth itfelf, which falls to the 
 bottom in form of a fine white meal, called at the works Alum meal : This is. 
 to be rediffolved and cryftallized afrefh. The mineral remaining after elixa- 
 tion, expofed for fome years to the air, becomes impregnated with Alum 
 again ; in fome places this procefs is repeated a third and a fourth time. 
 
 Some earths, as the Alum earth of Solfatara, and the aluminous dates, have 
 a manifeft aluminous tafte when newly dug; and hence are dire&ly eiixated,. 
 without expofure to the atmoiphere. In fome kinds of dates, we may plainly 
 diftinguilh the aluminous matter lying in a powdery form, betwixt the flakes 
 or fcales of which the ftone is cotnpofed. In general, where the mineral holds 
 but little Sulphur, it is diffident to lay it for a time in the open air, defended 
 from rain by a fhed or flight covering : If it participates confiderabiy of Sul- 
 phur, it muft be previoufly calcined: If very rich in Sulphur, a part of 
 
Minebal Salts. 187 
 
 the Sulphur is firft extradted by fubiimation, and the refiduum worked for A l u m. 
 Alum. ' J 
 
 The Alum flates near York in England are confiderably fulphureous: By 
 lying long in the air, they become aluminous of themfelves, but to promote 
 this effecft they are ufuaily calcined. The boilers are large leaden pans, nine 
 feet long, five feet broad, and two and a half in depth : The liquor is clari- 
 fied anddifpofed to cryftallize by the addition of Soda, there called Kelp, and 
 of urine. The Alum-ore of Schwentzel near Duben in Saxony, above five 
 miles from Hall, is likewife bituminous : This is firft calcined, then expofed 
 to the air, elixated with water, and the liquor boiled down with Potafh. At 
 Altfattel near Car Ifbade, the workmen, when I was there, ufed only urine, of 
 which they received conftant fupplies from the neighbouring towns and villages. 
 
 The mod curious Alum-ore J know of is in Sweden •, Sulphur, Vitriol and 
 Alum being here obtained from one mineral, which appears to be a kind of 
 Pyrites. The Sulphur is firft extracted by diftillation : The refiduum being 
 ftrongly calcined, boiled in water, the liquor duly evaporated and fet to 
 fhoot, the Vitriol cryftallizes: The uncryftallized liquor, treated with urine 
 and a ley drawn from allies, yields Alum. 
 
 The cryftallization of Alum is ufuaily performed in large ftrong wooden 
 calks, whofe ftaves and hoops are all marked with numbers, that they may be 
 readily put together: In fome places Iron vefiels are ufed. The cafics being 
 filled with the Alum liquor evaporated to a due confiflence, and fet in a cold 
 place, the Alum gradually fhoots into large cryftals about the fides : The li- 
 quor in the middle is then let off by a cock in the bottom, the head of the cafk 
 knocked out, and theveffel turned upfide down, for the more effectual drain- 
 ing off of the remaining liquid. The cryftals are then dried in a warm ftove, 
 and packed up in cafks ; and the mother-ley, or uncryftallized liquor, mixed 
 with trefh aluminous leys. The metallic or vitriolic Alum-ores occafion the 
 greateft trouble ; and the Alum obtained from them, though it appears white, 
 is never totally free from fome metallic impregnation. Confiderable diffe- 
 rences are found in Alum, partly from this caule, and partly from its being 
 prepared with urine or Potafh, or with frefh orftale urine: Thefe differences 
 are chiefly obferved by the dyers, and thofe who prepare lakes for the painters. 
 
 Alum requires about ten times its weight of water to diffolve in. The folu-G enera i p r0 . 
 tion if the Alum was pure, makes no change in the colour of Syrup of Vio- perties. 
 lets (g) •, but the common forts change the Syrup green, by virtue of the alca- 
 line Salt employed in their preparation. Fixed alcalies, volatile alcalies, and 
 Borax, added to folutions of Alum, precipitate the earth. Its tafte is naufe- 
 oufly fweetifh and aftringent. In cryftallization, it fhoots into large angular 
 maffes, confifting generally of eleven planes, five of which are hexangular and 
 fix quadrangular. 
 
 An 
 
 (g) Alum changes the colour of Syrup of Flo - flowers and their infnfions or fyrups, to a 
 lets. J I have not obferved any fort of Alum purple or red, as acids do ■, like which alfo 
 to mix with Syrup of Violets without chang- it coagulates milk. It deepens fome watery 
 ing its colour. Common Alum changes tinctures of vegetables, as of Madder and 
 violets, cyanus flowers, and other blue Brazil, 
 
 B b z 
 
1 8 8 Mineral Salts. 
 
 Alum. An ounce of Alum contains about five fcruples and a half of earth, one 
 
 <- — dram and eighteen grains of vitriolic acid, and nearly five drams of water. 
 
 Anatyfis. That its acid is the fame with that ot Vitriol and Sulphur, appears from hence, 
 
 that it forms with metals a true Vitriol ; and with inflammable fubftances a 
 
 Effeds of fire true Sulphur Alum expofed to the fire, firfi: liquefies and boils up like 
 
 green Vitriol; and when its phlegm is evaporated, forms a white fpongy brittle 
 mafs : By this treatment it lofes very little of its acid, and hence almoft totally 
 dili'olves again in water, and llioots into hard compari: eryftals as at firfi:. The 
 calcined or burnt Alum, as it is called, proves fharper in tafle than crude 
 Alum, on account of the lofs of its phlegm; and imbibes humidity from the 
 air : Four ounces will, in the fpace of a month, gain an increafe of one ounce. 
 Dr. Rhuon expofed equal quantities of burnt Alum, for equal lengths of time, 
 in a damp cellar, and in a dry upper room : The firfi: gained half an ounce, 
 
 the latter only five fcruples. If we attempt to extrari: the phlegm and acid of 
 Alum by diftiliation, we mull either injebtthe Alum by a little at a time into 
 a tubulated retort, or put it into a common retort of which it may fill no more 
 than one half, and apply the fire in fuch a manner, that the matter may be 
 heated firfi: on the furface, and thence gradually to the bottom. Though the 
 fire is kept up ftrong for a confiderable time, we can fcarce gain more than 
 half the weight of the Alum, of a phlegmatic fpirit : The refiduum expofed to 
 the air, imbibes moifture, and then yields more of an arid fpirit, the phlegm 
 ferving for a vehicle to the acid. Alum diffolved repeatedly in vinegar, parts 
 with its water more eafily than at firfi:: It now calcines into a white mealy 
 vinous fpirits. powder, in a warm room, or by the heat of the fun. If Alum be deprived of 
 its phlegm by moderate calcination, its acid will be in great part abforbed by 
 rectified Spirit of Wine: On diftilling off the fpirit, and cohobating it feveral 
 times on the refiduum, a Spiritus vitrioli dulcis will be obtained. 
 
 Schroder relates, that if the phlegmatic Spirit of Alum be cohobated on the 
 remaining burnt Alum, and this procefs feveral times repeated, the whole 
 quantity of the Alum will at length arife over the helm by the heat of a water 
 bath : But this is direrily contrary to experience. There are two preparations 
 of Alum, whofe names leem to imply a change made in its quality or fome 
 particular matter extracted from it : One is called Alumen faccharinum , the 
 other Saccharum , manna , dulcedo , and primum ens , aluminis. If we expeft in 
 thefe preparations what their names import, wefhall be greatly deceived : The 
 firfi: is no other than crude Alum foftened into a pafte with whites of eggs and 
 rofe-water, and made up into the form of fugar loaves : The other is compofed 
 fometimes of crude and fometimes of burnt Alum., made up with common 
 water, Rofe-water, Lime-water, Vinegar, or phlegm of Alum. Some cal- 
 cine the Alum, then diffolve it in water, and evaporate the folution ; and call 
 the Salt thus prepared, Sal fixum aluminis ; though in no refperi different from 
 crude Alum. 
 
 Black Phof- Alum calcined with inflammable fubftances,. particularly thofe of the animal 
 phorus. kingdom, forms a concrete which takes fire fpontaneoufly on the admiflion of 
 air, and which is hence diftinguifhed by the name of Pyrophorus. This prepa- 
 ration was firfi: made publick by Homberg, and ufually bears his name 
 though, as Geoffroy informed me, Homberg himfelf learnt it from another 
 
 perfoiio. 
 
 on it. 
 
 and pf sir. 
 
 vinegar, 
 
Mineral Salts. 189 
 
 perfon. The fame product occurred alfo to me, in making fome experiments Alum. 
 in London, with a different view; and Lemery has given a fet of experiments — v— 
 
 exprefsly on the fubjedt. The bell: method of preparing this Pyrophorus is, 
 to mix powdered Alum with fo much yolk of eggs as will reduce it to the con- 
 fidence of thin honey, and keep the matter conftantly ftirring over a gentle 
 fire, breaking from time to time fuch lumps as may form in it, till the whole 
 is changed into an uniform dry powder. This is to be put into a viol, the 
 veffel (lightly ftopt with paper, fet in fand in a crucible over a gentle fire;, 
 which is to be gradually increafed, till the fumes ceafe, and the matter is mo- 
 derately calcined: As foon as the heat has abated a little, the viol is to be 
 clofely ftopt. If a little of this powder be at any time emptied out on a piece 
 of paper, it will prefently take fire and burn like a coal. 
 
 Alum is ufed in large quantity in fome mechanic bufineffes ; particularly by UfesofAlam. 
 thedyers, paper-makers, goldfmiths, bookbinders, for preferring watery liquors 
 from corruption, for preferving anatomical preparations, and in the embalming 
 of animal bodies: It is far more powerfully antifeptic than the Vitriols. As a 
 medicine, it is a ftrong aftringent, and hence is fometimes exhibited in hae- 
 morrhages, dyfenteries, and intermittent fevers; but is not to be ventured 
 on in either of thefe cafes, without extreme caution : Some of the Englifh 
 phyficians follow Helvetius’s method of mixing the Alum with dragons blood. 
 
 Externally it is employed againft inflammations of the eyes, in gargariftns for 
 fwellings and inflammations of the throat, and for relaxations of the uvula. 
 
 II. BITTER PURGING SALT. 
 
 T HIS Salt was originally prepared from the purging mineral waters of Ep- Bitter purg- 
 fom in Surry, and hence is ftill diftinguifhed by the name ofEpfom Salt. in 2 Salt » 
 
 Dr. Grew publifhed fome experiments upon the water and Salt ; which occa- 
 fioned them to be brought into fuch general ufe, that the quantity procurable 
 from the fpring was infurficient for the demand. Attempts were made to 
 prepare from other materials a Salt of the fame properties, and with fuccefs ; the 
 analyfis difcovered by the gentleman above-mentioned, having afforded fome 
 foundation to proceed upon. Large quantities of the factitious Salts continue 
 to be exported to France, Germany, GV. and are fold at a very cheap rate. 
 
 The natural waters ofEpfom are now little regarded ; and in 1713 i found no 
 perfon there who could give any information about the preparation of the Salt. 
 
 I infpiffated myfelf an hundred quarts of the water, but fcarce'y obtained from 
 them half an ounce of faline matter. 
 
 Boulduc relates that theEpfomSalt is made by precipitating afolution ofAlum 
 with Salt of Tartar, and cryftallizing the remaining liquor. But in this he is 
 manifeftly miftaken ; for fuch a procefs can afford no other than a vitriolated 
 Tartar ; whereas the Epfom Salt, and the Saks of the natural purging waters, 
 are fimilar to the Sal mirabile, of which hereafter. After many wearifome en- 
 quiries, I found at laft, that this Salt was prepared in quantity near Portl- 
 mouth, from the mother lev or uncryftaliized liquor left in the purification of 
 the Bay- fait imported from Spain and Portugal. The Epfom Salt is compofed 
 of an alcaline earth combined with vitriolic acid: This liquor contains the 
 
 earth* 
 
19 ° Mineral Salts. 
 
 Purgtng earth, combined perhaps in part with marine acid : All that is wanting 
 Salt, therefore is an addition of vitriolic acid to difiodge the marine, and for this 
 v - — 1 purpofe the Me of Wight affords Pyritas in abundance. The method at that 
 time was, to infpiffate the mother- ley, add a portion of the liquor of the py- 
 rites, (lightly calcine the mixture, and then diffolve, and cryftallize the Salt : 
 But probably fome improvements have fince been made in the procefs. I 
 communicated thele cbfervations in the year 1714 to Dr. Lentilius in Hol- 
 land, who published them without my knowledge, inaccurately and imper- 
 fectly, in the Ephemeridcs nature curiofcrum (b). 
 
 Article IV. 
 
 Combination of the vitriolic acid with alcaline Salts. 
 
 Vitriolated ^’TT'H E vitriolic acid, faturated with vegetable fixt alcalies, forms a bitterifli 
 Tartar. X neutral Salt, which fhoots into fmall hard cryftals. This Salt is re- 
 v — —J markably ponderous ; more fo than either the acid or the alcali by themfelves. 
 Its properties. anc } th an an y faline cotripound I know of, excepting thofe which abound with 
 metallic matter, as Mercury-fublimate. It retains in its cryftalline form, only 
 a fmall portion of water. It does not imbibe humidity in a moift air, nor be- 
 come powdery in a warm dry one. It is very difficultly foiuble in water ; being 
 fcarce at all aCted upon by cold, and requiring a large proportion of boiling 
 water: Spirit of wine, added to the folution, precipitates the Salt in form of a 
 
 white 
 
 (/;) Bitter purging Salt .] This Salt, which 
 is now extracted by cryftallization from the 
 bittern of fea-water, or the bitter liquor 
 which remains after the culinary Salt has 
 (hot, is fometimes fubftituted in the (hops 
 to the cathartic Salt or Salmirabile of Glau- 
 ber : Some have fuppofed the two Salts 
 to be perfedlly fimilar, and indiftinguifhable 
 from one another. 
 
 They agree in having a bitterifh tafte ; 
 diffolving in lefs than an equal weight of 
 water; (hooting into long rectangular prif- 
 matic cryftals ; liquefying in a moderate 
 heat, bubbling up into blifters, and foon 
 changing into a white fpongy mafs, with 
 the lofs of above half their weight of phlegm, 
 whence the calx taftes bitterer than the Salts 
 did at firft ; and in their being compofed of 
 the vitriolic acid united with an alcaline 
 bafis. 
 
 They differ in the nature of this bafis; 
 that of the bitter purging Salt being a pecu- 
 liar kind of abforbent earth, and that of 
 Glauber’s Salt a true fixed alcaline Salt. 
 On adding any alcaline Salt, fixed or vola- 
 tile, to a folution of Glauber’s Salt, no 
 
 change enfues ; whilft the Salts obtained 
 from the purging waters, or from the bit- 
 tern of marine waters, grow milky or curdly 
 on this addition, and depofite their earth, 
 the alcaline Sait being taken up in its 
 place. Thefe Salts are therefore truly and 
 effentially diftinCt, and very readily diftin- 
 guifhable, notwithftanding their agreement 
 in fome of their more obvious appearances. 
 
 The earth of the bitter purging Salt is 
 called Magnefta alba ; and its principal cha- 
 racter is, to form with the vitriolic acid a 
 bitter purgative compound. I have no 
 where met with this earth in the mineral 
 kingdom, but in the cathartic Salt itfelf, 
 and in the mother-ley of Nitre, or the li- 
 quor which remains after the cryftallization 
 of rough Nitre. The earth into which ve- 
 getable fubftances are reduced by fire (at 
 leaft the woods and herbs which I examined) 
 is exadtly the fame with this; and probably 
 it is from the vegetable afhes employed in 
 the preparation of Nitre, that the nitrous 
 mother-ley receives its magnefia. The in- 
 cinerated earths of animals are of a different 
 kind. 
 
Mineral Salts. 
 
 191 
 
 white powder like meal. It does not melt in the fire, nor part with any of its Vitriolated 
 acid, nor fuffer any fenfible change. Diffolved in water, it proves in part vo- Alcaljes. 
 latile by the heat in which water boils : By ftrong continued co&ion, it may at ^ 
 
 length be totally diffipated along with the watery vapour. 
 
 borne differences are obferved in the quantity of the acid and alcali neceffary Experiments 
 for the faturation, and in the phenomena attending the procels, according as 0 / tiie fatura - 
 the plain or cauftic alcali is ufed, and according to the manner in which the 
 mixture is performed. I prepared a cauftic alcali, by mixing one ounce of w ; t h vitriolic 
 pure alcaline Salt with two ounces of Quick-lime, boiling the mixture in frelhacki, 
 parcels of water till the liquor no longer acquired any faline tafte, then filtering 
 the feveral decodions, and evaporating them together to drynefs. The dry 
 Salt weighed two fcruples and a half more than the alcali employed - y and the 
 remaining Lime weighed a dram lefs than at firft. 
 
 To a dram of this cauftic Alcali,' rubbed into powder, Spirit of Vitriol was 
 added by degrees, till the Salt was diffolved and the efferveicence ceafed : The 
 quantity of the fpirit neceffary for this purpofe was two drams. During the 
 efferveicence, a bright browniffi earth fell to the bottom, which weighed when 
 dry three grains : The filtered liquor depofited in evaporation firft five grains 
 and a half of white earthy creme, and afterwards five grains of a yellowifn one: 
 
 The dry Salt weighed two fcruples and eight grains. During the faturation 
 arofe an abominable urinous fmell, from which the exficcated Salt was not 
 wholly free. 
 
 On inverting the order of mixture, and adding the Alcali by degrees to the 
 acid fpirit, fourteen grains of the former were found fufficient for faturating two 
 drams of the latter. The fame kind of ftench arofe during the efferveicence 
 as in the foregoing experiment, and a blackiffi-grey matter fell to the bottom, 
 amounting when dry to fourteen grains : The filtered liquor left on evapora- 
 tion a dry Salt weighing half a dram all but half a grain. 
 
 I repeated both thefe experiments with a pure fixed Alcali. A dram of this 
 required for its faturation three drams of Spirit of Vitriol : The liquor left no- 
 thing confiderable on filtration, and being afterwards evaporated, yielded of 
 dry Salt, partly cryftalline, four fcruples wanting one grain. 
 
 On inverting the procedure, and taking three drams of the acid fpirit 
 firft, one dram and nine grains of the pure Alcali were neceffary for the fatura- 
 tion, and half a dram of a white Precipitate fell to the bottom : On evaporating 
 the filtered liquor, the dry Salt, cryftals and all, weighed two fcruples and 
 two grains. 
 
 When the alcaline Salts were previoufty diffolved in water, fome further dif- 
 ferences were observed. A dram of cauftic Alcali diffolved in half an ounce of 
 diftilled water, required for its faturation juft two drams of Spirit of Vitriol, 
 as the fame quantity of the Salt had done in its dry ftate: But no urinous fmell 
 was here perceived, and a fcruple of a reddifh earthy matter precipitated. The 
 filtered liquor evaporated a little, gave eighteen grains of cryftals, and the re- 
 mainder infpiffated gave fixteen grains of dry Salt. 
 
 On the other hand two fcruples of Spirit of Vitriol being faturated by gra- 
 dual additions of the cauftic alcaline folution, two fcruples and eight grains of 
 the Alcali were found fufficient : During the effervefcence, there fell half a 
 
 dram 
 
192 Mineral Salts. 
 
 Vitriolateddram of an afh-grey Precipitate : The filtered liquor gave firft half a fcruple cf 
 Alcalies. greyifh cryftals, and on being afterwards evaporated to drynefs left fifteen 
 grains of Salt. 
 
 A dram of pure fixed Alcali difiolved in half an ounce of dillilled water, re- 
 quired to faturate it three drams of the acid fpirit, and gave no precipitation : 
 The filtered liquor evaporated a little, yielded twenty-two grains of cryftals, 
 and on further evaporation two fcruples and two grains of Salt. The acid be- 
 ing taken firft, and the alcaline folution added to it, two fcruples of the Alcali 
 completed the faturation ; the liquor being filtered and evaporated, eight grains 
 of the neutral Salt fell in form of a Precipitate, twelve and a half cryftallized, 
 and twenty-fix remained upon continuing the evaporation to drynefs. 
 
 ■Different me- The neutral Salt compofed of vegetable fixed alcalies and the vitriolic acid, 
 thods of pre-is commonly called vitriolated Tartar, and employed in medicine as an ape- 
 parmg vitno- r ;. ent anc j gentle laxative. It was formerly prepared by mixing the diluted acid 
 ate artar ' with a dilute folution of the Alcali, fetting the liquor after due evaporation to 
 cryftallize, and then further evaporating the remainder to drynefs: By this 
 method, as the exa6t point of faturation is difficultly hit, the Salt frequently 
 proved too acid ; and hence its ufe was by many pra&itioners laid afide. Otto 
 Tachenius introduced a method more advantageous to the operator, and by 
 which the medicine may be effectually fecured againft a redundance of the acid 
 pr the Alcali •, inftead of the acid extradted from Vitriol, he rakes a folution of 
 Vitriol itfelf : On the addition of an alcaline Salt to this folution, .the acid of 
 the Vitriol lets fall the metallic part, and unites with the Alcali into the neutral 
 Salt required, which is recoverable from the liquor by filtration and cryftalliza- 
 tion. It was a confiderable time before this method was received in practice, 
 nor was the foundation of the procefs known till Stahl difcovered it. The 
 neutral Salt thus prepared was called a regenerated Vitriol, and Salt of Vitriol, 
 fuppofed by Tachenius, Boyle and others, to yield its acid in diftillation in 
 the fame manner as common Vitriol, to participate of the metallic matter of 
 the Vitriol, whether ferrugineous or cupreous, as well as of the acid. That it 
 may participate of the metal when incautioufly prepared is certain : Hence it 
 frequently occafioned naufea, ficknels, and even vomiting: Tachenius hitn- 
 
 felf gives it the title of Sal vomitivum. Thefe inconveniences depended wholly 
 upon the proportion of Alcali made ufe of being too fmall to faturate all the 
 acid, and conlequently to precipitate all the metal. 
 
 To obtain a pure and perfect neutral Salt, the Alcali fhould be taken in 
 over-proportion •, the Vitriol is firft to be difiolved in boiling water, and a fo- 
 lution of Potafh or other fixed alcaline Salt gradually added, till the faturation 
 appears completed ; fomemore of the alcaline liquor is then to be poured in, 
 the whole ftirred together, the liquor filtered, evaporated till a pellicle appears 
 upon the lurface, and then fet to cryftallize. By this means we are lecure 
 againft any metallic taint, and as to the fuperfluous Alcali it will not cryftal- 
 hze : Such part of the Alcali as may adhere fuperficially to the cryftals is eafily 
 feparated by rinfingthem in water. The liquor which remains after the cry- 
 ftallization is to be further evaporated, and fet to ffioot again : After it will 
 
 yield no more cryftals it may be mixed with frefii ingredients when another 
 quantity of the Salt is to be prepared. There is no occafion for purifying the 
 3 Potaffi 
 
M 
 
 I N E R A L 
 
 A L T S. 
 
 r 93 
 
 Potafh or other Alcali for this ufe, as it will be effectually purified in the pro- Vitriolated 
 cefs itfelf. Alcalies. 
 
 This is the moll commodious and certain method of procuring a vitriolated ^ v ~ — 1 
 
 Tartar perfectly neutralized, and has another advantage above that in which 
 the diftilled vitriolic acid is ufed, namely, that the fubtile volatile fpirit of the 
 Vitriol, called by Helmont Gas , which is diffipated in the calcination of the 
 Vitriol previous to its diftillation is here preferved. The fame neutral Salt 
 may be obtained by proceeding in like manner with a folution of Alum mftead 
 of Vitriol; or by calcining a mixture of Alum or Vitriol with a fufficient quan- 
 tity of alcaline Salt, and elixating the compound with water, the acid being 
 thus transferred from the earth or metal into the alcaline Salt as well as when 
 folutions of them are mixed, though with lefs certainty ; or by expofing cloths 
 moiftened with alcaline leys to the fumes of burning Sulphur ; or by melting 
 alcalies with Sulphur, and gently calcining the mixt till the inflammable part 
 of the Sulphur is diffipated ; or by expofing pure alcaline Salts for a length of 
 time to the air. The neutral Salts obtained by all thefe methods are perfectly 
 fimilar to one another; the acids of Sulphur, of Vitriol, of Alum, and that 
 which is difFufed through the atmofphere, being one and the fame. 
 
 The Nitrum vitriolatum , otherwife called Arcanum duplicatum , Panacea Holfa- Vitriolated. 
 ■tica, Sal duels Holfatia , Sal de duobus , &c. is no other than a vitriolated Tartar, Nitre, 
 made with the alcaline balls of Nitre, which is the fame with the common vege- 
 table alcalies. This is prepared by elixating with water the matter which re- 
 mains after the diftillation of the nitrous acid with Vitriol, the acid of the Vi- 
 triol having expelled the acid and united with the Alcali of the Nitre. As 
 the Vitriol, however, after this diftillation retains a part of its acid, lo as to 
 diffolve along with the neutral Salt in water, fome Potafh fhould always be 
 added to abforb the acid and precipitate the metal. 
 
 The fame Salt is produced by deflagrating Nitre with a due proportion ofSalpoly- 
 Sulphur, the acid of the Sulphur extricating that of the Nitre, and unitingchreih 
 with its alcaline bafis. The Salt thus prepared is called Sal poly chr eft um> or 
 JAitrum fulphuratum. 
 
 Both thefe Salts, though received in the fhops as diftinCt ones, are found 
 when made in perfection, to be fimilar in all retpeCts to one another, and to 
 the Tartarus vitriolatus. The differences fometimes obferved in them are en- 
 tirely calual : The Nitrum fulphuratum may contain a portion of the Nitre un- 
 changed ; and both of them, if the Nitre employed participated of Sea-falt, 
 will hold a proportionable quantity of Sal mirabile. 
 
 Sal mirabile , l'o called by its firft difeoverer Glauber, is a combination of tlie Q]„ u p )ers 
 vitriolic acid with the alcaline bafis of Sea-falt. As this Alcali is very different 
 from the common vegetable Alcalies, it forms with the vitriolic acid a different 
 neutral Salt, in tafte more bitter, as a medicine more purgative, eafily foluble 
 in water, and when diffolved coagulating on the admixture of Spirit of Wine ; 
 eafily fufible in the fire, and difeharging a large quantity of aqueous phlegm, 
 calcining by a gentle warmth into a white powder. This Salt is prepared from 
 the matter which remains after the diftillation of Spirit of Sea-falt with Oil of 
 Vitriol or with Vitriol in fubftance : It may be obtained alfo from the refiduum 
 after the fubiimation of Mercury-fublimate, when Sea-falt and Vitriol, or its 
 acid without Nitre, are employed in that procefs. 
 
 C c The 
 
1 94 
 
 Vitriol ated 
 Alcalies. 
 
 Vitriolic am- 
 rnoniacal Salt. 
 
 Mineral Salts. 
 
 The vitriolic acid faturated with volatile alcalie9 forms a neutral ammoniacal 
 Salt, called Sal ammoniac um fecretum (z). 
 
 CLASS 
 
 (z) Secret Sal ammoniac , or vitriolic ammo- 
 niacal Salt.) This Salt has a penetrating 
 pungent tafie ; and when newly prepared, 
 a fulphureous fmell, greater or lefs accord- 
 ing as the volatile (pint made ufe of was 
 more or lefs loaded with oily matter. It 
 readily difTolves in water, and increafes the 
 coldnefs of the liquor: Onftandingfor alittle 
 time, it begins to feparate from the water, 
 and vegetate or arife in efflorefcences up the 
 hides of the glafs On moderately evapo- 
 rating the folution, the Salt fhoots into fib- 
 rous plates like feathers. It eafidy melts in 
 the fire, penetrates the common crucibles, 
 and in glafs veflels fublimes unchanged. 
 
 On expofing to the fire a mixture of this 
 Salt with Sea-falt, two new combinations 
 happen : The vitriolic acid quits the vola- 
 tile Alcali, and unites with the fixed alca- 
 line bafis of the Sea-falt into a Glaubers 
 Salt ; whilfl the marine acid, thus dillodged 
 from its own bafis, unites with the volatile 
 Alcali, which the vitriolic had forfook, into 
 a common Sal ammoniac. The acid of 
 Nitre is alfo in like manner expelled by the 
 vitriolic ammoniacal Salt. On adding this 
 Salt to a folution of any calcareous earth, 
 as Chalk, in the nitrous, marine, or vege- 
 table acids, the vitriolic acid forfakes its 
 Alcali to unite with the earth, with which 
 it forms a felenitic concrete, which renders 
 the liquor milky or curdly, and on Handing 
 falls to the bottom : By this mark, the vi- 
 triolic is readily diflinguifhable from the 
 other ammoniacal Salts, thefe making no 
 change in calcareous folutions. 
 
 This Salt is called fecret or philofophic Sal 
 ammoniac, from the high opinion, which 
 feme of the chemifls have entertained of 
 its activity upon metals. Mr. Pott has given 
 feveral experiments on this fubjedf in the 
 Berlin Memoirs ; from which it appears, 
 that its efl'edls have been greatly exagge- 
 rated ; that it difTolves or corrodes in fome 
 degree all thofe metals which Oil of Vitriol 
 difTolves, but has no effedlupon thoTe which 
 that acid does not act on by itTelf. 
 
 Gold is not touched in the leafl, either 
 by the Salt in fufion or by a folution of it : 
 The Salt, added to a folution of Gold in 
 
 Aqua regia occaftons no precipitation or 
 change of colour. On melting the Salt 
 with inflammable matters, it forms a ful- 
 phureous compound, which difTolves Gold 
 in fufion, in the fame manner as compofiii- 
 
 tions of Sulphur and fixed alcaline Salt 
 
 The vitriolic ammoniacal Salt, melted with 
 Silver, corrodes it into a white calx, which 
 partially difTolves in water : It likewife pre- 
 cipitates Silver from its folution in Aqua 
 fords -It a£ls more powerfully on Cop- 
 
 per, elevates in fublimation a part of the 
 metal, fo as to acquire a bluifh colour on 
 the furface, and renders greateft part of the 
 refiduum foluble in water. Tfiis folution 
 appears colourlefs, infomuch that it could 
 not be fufpecHed to hold any Copper : It 
 readily difeovers however, that it abounds 
 with that metal, by the blue colour which 
 itaffumes on the addition of volatile alcalies, 
 and the green calx which fixed alcalies pre- 
 cipitate: In evaporation, it becomes green, 
 without any addition. The vitriolic acid, 
 in a concentrated Hate, remarkably deftroys 
 the colour of cupreous folutions : If to a 
 faturated blue tindlure of this metal in vola- 
 tile fpirits, fome Oil of Vitriol be added, 
 the blue colour will inflantly difappear, and 
 the liquor become limpid as water : On 
 adding more of the volatile fpirit, the colour 
 
 as readily returns Iron is corroded by 
 
 the Salt in fufion, and diffolved by boiling 
 in a folution of it- — Zinc difTolves more 
 freely and more plentifully — Lead unites 
 with it, but does not become foluble in 
 water — Tin is corroded, and a fmall portion 
 of the calx difTolves in boiling water — Of 
 Regulus of Antimony alfo a fmall portion 
 is made foluble : Alcalies precipitate from 
 the folution a bluifh powder —Calcined Bif- 
 muthore, treated with equal its weight of 
 the Salt, partly diffolved in water into a 
 pale red liquor, which became green from 
 heat, in the fame manner as tin&ures made 
 from that ore by Aqua regia : The undif- 
 folved part yielded Hill with fritt a blue 
 
 glafs On treating Manganefe in the fame 
 
 manner, aluminous cryflals were obtained : 
 The undiffolved part of the Manganefe gave 
 Hill a violet-purple colour to Glafs. 
 
Mineral Salts. 
 
 CLASS II. 
 
 Nitrous acid and its combinations. 
 
 T H E nitrous acid is the moft limited and lead frequent in the earth of all Nitrous 
 
 the mineral acids. It isfeldom met with in any combination but in the Acid. 
 
 neutral Salt from which it receives its name, and feems to be in that, rather 
 an artificial than a natural production (fee Nitre). It is fuppofed by fome to Produftion. 
 be an offspring of the marine acid, with little probability ; for the nitrous acid 
 is more powerful than the marine, expelling it from alcaline Salts and earths, 
 which it is not likely it fhould do if it received its origin from that acid. Others 
 fuppofe it on better foundation to be truly the vitriolic acid, altered by putre- 
 faction, and the commixture of fome inflammable matter. In proof of this 
 opinion, an experiment is alledged, in which the nitrous acid returns back 
 into the vitriolic: If two ounces of good Spirit of Nitre, and half an ounce of 
 
 Oil of Turpentine be digefted together, a balfam of Sulphur is produced pofi- 
 fefling all the properties of common balfam of Sulphur. We have already feen 
 that Sulphur confiffs chiefly of vitriolic acid* and whence could that add 
 be here furnilhed but from the nitrous? 
 
 The concentrated nitrous acid is weaker and much more volatile than theQ eneral 
 vitriolic. It is in part diflipated by the a&ion of the air in pungent vapours, perties. 
 which appear before their difperfion of a red colour: In diftillation it aril'es in 
 fumes of the fame colour. If an unftopt bottle of this fpirit, and one contain- 
 ing a volatile alcaline fpirit, be brought near to one another, the vapours of the 
 two liquors unite together, and form a white cloud in the air. An ounce of 
 the concentrated nitrous fpirit faturates near feven drams of fixed alcaline Salt, 
 and is found to contain about two drams and a half of pure acid, and five and 
 a half of water. 
 
 Article I. 
 
 Combination of the nitrous acid with inflammable fubflances. 
 
 T HE nitrous acid mixed with difiilled oils raifes a great heat and effer-jp eat anc j 
 vefcence, and forms with them a thick refinous mafs like Turpentine, flame with 
 If the acid is highly concentrated and mixed all at once with fome of the more oils ‘ 
 fubtile oils, the matter burfts immediately into actual flame (£). 
 
 It 
 
 (k) Flame from nitrous acid and oils.] This the mixture effervefces, fwells, and a light 
 experiment does not fucceed unlefs the acid fungous coal arifes : A little more of the 
 is highly concentrated, and even when it is, acid poured upon this coal fets it inftantly 
 there are few oils which it will fire with on fire : By this method, almoft all the di- 
 certainty, without the obfervance of a par- killed oils may be fired by Spirit of Nitre of 
 ticular circumftance firft difcovered by Mr. moderate ftrength. Expreffed oils alfo may 
 Rouelle, and communicated in the French be fet on fire by a mixture of the nitrous 
 Memoirs for the year 1747. On letting fall acid with an equal quantity of Oil of Vi- 
 into the oil equal its quantity of the acid, triol; the ufe of which laft feems to be to 
 
 C c 2 abforW 
 
s. 
 
 190 
 
 Nitrous 
 
 Acid. 
 
 Mineral Salt 
 
 With vinous 
 fpirits. 
 
 It raifes likewife a violent ebullition and heat with Spirit of Wine ; but this 
 mixture is never obferved, as fome have reported, to take fire. The fated 
 way of mingling thefe liquors is to pour the acid fpirit by a little at a time into 
 the vinous : If the mixture made with about one part' of the Spirit of Nitre to 
 eight of redtified Spirit of Wine be digeded for fome days, and then diddled in 
 a glais retort with a very gentle fire, till only a thick mucilaginous matter re- 
 mains, the diddled liquor difcovers a grateful fmell and tade without any aci- 
 dity, and hence is called dulcified Spirit of Nitre. I have often obferved this 
 dulcified fpirit vary in quality according to the purity of the acid and vinous 
 fpirits made ufe of, and the manner of preparation. Some of the dulcified 
 fpirits have coagulated watery tindlures of the flowers of plants •, fome have 
 weakened or dedroyed the red colour of the tindture of daily flowers, whild 
 others produced neither of thefe efiredts. 
 
 Two ounces of the concentrated nitrous acid diffolveone ounce of Camphor, 
 the Camphor imbibing the dronger acid, and forming with it an oil which 
 floats on the furface of the more phlegmatic liquor. Silver added to this fo- 
 lution throws out the Camphor, the acid diffolving the Silver in its place. 
 
 Deflagration. If the nitrous acid be combined with any fubdance whatever, that will detain 
 it in the fire fo as to receive a red heat ; on the contadt of any inflammable 
 matter in that date it either explodes or deflagrates, that is, burns and flafhes 
 with a hiding noife. All inflammable iubdances, as bones, hair, &c. and me- 
 tallic bodies that abound with phlogidon, occafion a detonation with this acid, 
 whether added to combinations of it in the fire or diffolved in the pure acid, 
 and after evaporation urged with a confiderable heat. The acid is dedroyed cr 
 diffipated during the deflagration. 
 
 With Cam- 
 phor. 
 
 Article II. 
 
 Combination of the nitrous acid with metallic bodies .. 
 
 With metallic 
 •fubftances. 
 
 T HE nitrous acid difiolves or corrodes all metallic bodies except Gold; 
 
 and this alfo it is enabled to diffolve by a fmall admixture of marine 
 acid. Silver, Copper, Iron, Lead, Quickfilver, Bifmuth and Zinc, are 
 more readily and violently ailed upon by this than by any other acid : With 
 Copper it forms a green, with Iron a reddifh, with Lead a yellow, with the 
 others, colourlefs liquors. Tin it difiolves imperfeitly, and Regulus of An- 
 timony it only corrodes into a powder. 
 
 Its a ilion on mod metallic bodies, unlefs the metal is cautioufly added by 
 little and little at a time, is accompanied with a confiderable heat, effervelcence, 
 and a copious difcharge of red fumes, which are found to be the dronger and 
 more fubtile part of the acid. Its action is mod vehement on thofe metals 
 
 which 
 
 abforb the aqueous humidity of the nitrous, produces adlual flame with them, 
 and thus reduce it to a greater degree of The nitrous acid mixed with powdered 
 concentration or ftrength than it can be ice, remarkably increafes its coldnefs : The 
 brought to by itfelf. The other mineral marine acid has this effedl in a fomewhat 
 acids raife an effervefcence and heat with Iefs degree, whild the vitriolic produces heat 
 oils, but the nitrous is the only one that with ice. 
 
Mineral Salts. 197 
 
 which appearently contain mod inflammable matter, as Zinc and Iron: Cakes Nitrous 
 and croci, or metallic bodies deprived of their phlogiftic principle it has no Acid. 
 effeCt on. The folutions made with it are in general of a bitter and very nau- — v— — ^ 
 
 feous tafte. 
 
 If Silver be diflolved in this acid and Mercury added to the folution, the acid General afR- 
 will depoflte the Silver, and diflolve the Mercury in its place. If Lead benities. 
 added to the mercurial folution the Mercury will fall, and the Lead be dif- 
 folved. The Lead in its turn will be thrown down by Copper, the Copper by 
 Iron, and the Iron by Zinc. Volatile alcaline Salts ablbrb the acid from all 
 the metals, and fixt alcalies from the volatile. The nitrous acid diflodges the 
 marine from fome of the metals, as Regulus of Antimony, but the marine dif- 
 unites the nitrous from Mercury and Silver. 
 
 Article III. 
 
 Combination of the nitrons acid with alcaline Salts. 
 
 T H E nitrous acid faturated with volatile alcalies, forms with them a neutral With alcalies* 
 ammoniacal Salt, which feparated from the watery phlegm by cryftalliza- 
 tion, is found to differ remarkably from the other Saks of this kind, in being per- 
 fectly diffoluble in highly rectified Spirit of Wine ; and in deflagrating when con- 
 derably heated, without any addition, efpecially if the volatile Alcali employed 
 was an oily animal -fpirit : From this property it received the name of Nitrum 
 fiammans. This acid forms with the alcaline bafis of Sea-falt a neutral Salt 
 which fhoots into cubical cryftals, and hence called Nitrum cubicum. With 
 vegetable fixed alcalies it cryflallizes into long hexangular prifms, the common 
 Nitre of the fhops. 
 
 NITRE or SALTPETRE. 
 
 THE Nitrum or Natrum of the ancients, which was a natural production, ^ l T R 
 appears from the feveral accounts given of it, to have been very different < ] 
 
 from our Nitre. The fpecirrrens I have leen dilcovered nothing of the peculiar Of the an- 
 properties of Nitre or its scid, and were no other than Sea-falt mixed with a cients * 
 little Alcali, and fometimes Sal ammoniac and Borax, 
 
 Nature affords no perfeCt Saltpetre: The accounts given by Boerhaave, Le- True Nitre 
 mery and others, of Nitre being found native in the Eaft-Indies, of its lying never natjve ' 
 on the furface of the ground in open fields fo as to be fwept up by brooms, are 
 neither fupported by any good authority nor eonfiffent with the properties of 
 Saltpetre. This Salt at the time of its firft production is fo volatile, that in 
 open fields in thofe warm climates, the fun’s heat would difflpate it : How can 
 it Hand the rains on the furface of the open ground ? Whence does it receive 
 the vegetable Alcali, which is the bafis of Nitre, and which does not exift in 
 the mineral kingdom ? We may be a flu red that cryftalline Nitre, from the 
 Indies, or whence foever it comes, has been manufactured by art; that art has 
 fupplied its alcaline bafis and reduced it into a cryftalline form. The acid is 
 produced by a natural procefs, putrefaction ; but the Alcali is a creature of 
 
M 
 
 I N E R A L 
 
 Salt s. 
 
 J 
 
 N i t r E.art alone : We fometimes meet with efflorefcences of earthy matters impreg- 
 
 ; — — i nated with the nitrous acid, but very different from true Nitre, and commonly 
 
 dilfinguilhed by the names of Nitrum calcar eum , Nitrum murarium , Apbronitrum , 
 
 Exifts not in 
 waters or in 
 the air. 
 
 Its producli- 
 <sn. 
 
 Nitrous fer- 
 ments. 
 
 and Halinitrum. 
 
 Many have affirmed that a perfect Nitre exifts in waters, and in the atmo- 
 fphere ; but experiment difcovers no fuch Salt in either. In waters the Sal 
 mirabile, or bitter purging Salt, has been miftaken for Nitre, from its ffiooting 
 into cryftals of a fimiiar figure. That thunder and lightening proceed from 
 Nitre is a groundlefs prefumption •, and that the firing of gunpowder can im- 
 pregnate the air with Nitre is apparently faife ; the diftingui filing principle of 
 the Nitre in the compofition of gunpowder is deftroyed in the explofion. 
 
 For the production of the nitrous acid are requifite (i.) putrid or putrefcible 
 matters, either of the animal or vegetable kingdom; (2.) certain earths, as 
 lean Clays, Lime-ftone, Gypfum, the rubbiffi of old buildings, &V. and (3., 
 air. The putrifying matters afford an oily urinous Salt : The ufe of the 
 earths leems to be to imbibe and retain this Salt, whilft the air ferves not only 
 as a neceffiiry inftrument of putrefaction, but furnifhes its own vitriolic acid, 
 which being intimately blended with the oily and urinous matter by means of 
 heat and the motion of putrefaction, is at length converted into nitrous acid. 
 
 All animal and vegetable fubftances contribute to the production of Nitre, 
 in fo far as they are fufceptible of putrefaction. Animal fubftances as being 
 moftdifpofed to putrefy, are for this ufe the moft proper; and the foft and 
 fluid parts more fo than the Tolid or hard. The greateft quantities of Salt- 
 petre are produced from urine and dung, whofe ftrong tendency to putrefaction 
 renders them preferable to any other matters. Some differences are obferved in 
 the excrements of different animals : Human urine, the urine of fheep, goats, 
 and horfes, and the dung of pigeons, are found to anfwer beft. The leaves, 
 flowers, ftalks of vegetables, hay and ftraw, faw-duft, are mixed in the 
 compofition, and contribute more or lefs to the effeCt according to their degree 
 of putrefeibility. On thefe principles Nitre may be produced in all countries ; 
 and in many places very advantageous works might be eftablifhed if we were 
 better acquainted with the manner of its production. 
 
 Certain earths may bedifpofed to this procefs, and improved fo as to afford 
 more and more Nitre by the admixture of different fubftances which may pro- 
 perly be called nitrous ferments. Lime appears to be particularly ferviceable 
 in this intention. The following compofitions are proper, (i.) Lime, fheeps 
 dung, fheeps urire, and common Salt. (2.) Lime, Salt, rafped horns and 
 hoofs, cuttings of leather, and other refufe animal fubftances. (3.) Human 
 urine and Lime. (4.) Human urine, Lime, Salt, and pigeon’s dung, and 
 other like mixtures of Lime and Salt with animal matters. (5.) Compofitions 
 of vegetables and animals together, as bitter plants boiled in urine and poured 
 on the earth. (6.) Tartar, Lime and urine. (7.) Lime, preffings of grapes, 
 and the liquor of dunghills. (8.) Wine lees, dunghill liquor. Lime and Salt. 
 (9.) Tartar and Lime. (10.) Lime, Salt, dunghill liquor, and the matter 
 remaining after the diftillation of Spirit of Wine. (u.)Lime, Salt, urine, 
 dung, and martial fcoria. Thefe compofitions may be varied, or others 
 formed on the fame plan, as different circumftances may require or permit. 
 
 A ni- 
 
Mineral Salts* ic>9 
 
 A nitrous Salt is produced without much affiftance from art, in places where Nitre. 
 putrefadHon is going on, in grounds frequently trodden by cattle and i'mprOg- t — -v— 
 nated with their excrements, where vegetables rot, about daughter- hou fes, wl E re £ ene * 
 lay- flails, and in burying-grounds, on old fhady walls expofed to putrid va- rate ' 
 pours, as thofe of (tables, pigeon- houfes, privys, near dunghills, i£c. The 
 earths into which the putrid matter moft readily infinuates itfelf for the pro- 
 duction of Nitre, are rather of the lean than the fat clayiekind, as mud-wali3, 
 Lime-ftones and other abforbent ftones. Some of the Saltpetre-makers, when 
 they have met with an earth fit for the purpofe, fpread it in the neighbourhood 
 of putrifying matters, where it may receive the putrid vapours. 
 
 The earth is of no further ufe in this procefs than as a matrix to imbibe and 
 retain the nitrous matter: It contributes no more to the product ion of Nitre 
 than alcaline Salts to the production ot the water which they at trad from the 
 atmofphere. Though Sea-falt promotes the procefs, it does not appear to fur- 
 nifh any material principle to the Nitre, and feems to be of no further ufe than 
 as it haftens putrefaction. The aereal acid intimately blended with putrefcent 
 exhalations in the pores of fpongy ftones or earths, is fo far as we can judge, 
 the true parent of the nitrous acid. 
 
 The nitrous matter thus produced is by no means perfeCt Saltpetre. It is Imperfe® 
 diflipated from the earths by the fun’s heat; and hence Nitre- works are com- Nitre, 
 moniy made to face the North, and the largeft quantities of nitrous matter are 
 found on the North-fides of wall. It exhales upon ftrongly boiling the earths 
 in water. Extracted by water it does not cryftallize; the liquor gently eva- 
 porated leaves only an unCtuous faline mafs, which liquefies again in the air. 
 
 With inflammable fubftances it deflagrates much more languidly than true 
 Nitre. To convert this volatile or calcareous into a perfeCt Saltpetre, by fub- 
 ftituting a pure fixed alcaline Salt to the impure volatile or earthy matter here 
 combined with the acid, is the bufmefs of art. 
 
 In moft of the German Nitre-works, a mixture of two parts of afhes of Extracted and 
 hard wood and three of Quick-lime is ftratified with the nitrous earth, in large made perfeft. 
 wooden cafks, the cock at the bottom being kept clear from the earth by a 
 bafket or fome ftraw placed round it. The veffel is filled up with hot water, 
 the liquor after (landing for fome time drawn off, frefh water added, and this 
 repeated fo long as it extracts any faline tafte. The elixated earth is expofed 
 again for fome years to the aft ion of the air and putrid exhalations, and thus 
 becomes again impregnated with Nitre. Some infteadof intermixing the Lime 
 and afhes with the earth, fprinkle an alcaline ley upon the earth before its elixa- 
 lion, or mix it with the ley drawn from the earth. In fome places the nitrous 
 ley of the very firft running is fo weak, that it is neceftary to ufe it in (lead of 
 water for a frefh tub of earth— — - The liquor is gently boiled down to a due 
 confidence, and then let to cryftallize, the fcum which arifes during the boil- 
 ing being occafionally taken off. The workmen judge of the proper con- 
 fidence for cryftallization, by a little of the liquor poured on a cold Iron 
 quickly congealing, and of its being fufficiently faturated with the alcaline ad- 
 dition, by the dry matter quickly deflagrating on a burning coal. The liquor 
 which remains after the cryftallization is further evaporated and fet to fhoot 
 again: When nothing more will fhoot, it is poured upon frelh nitrous earths, 
 
 5 
 
200 
 
 Mineral Salts. 
 
 Nitre. 
 
 Purification, 
 
 &c. 
 
 Marks of its 
 purity. 
 
 General pro- 
 perties. 
 
 or employed for the preparation of Magnefia, of which hereafter — — Trial 
 has been made of alcaline Salts by themfelves, and of Lime by itfelf ; but 
 neither of them fucceeded fo well as a mixture of the two, either for forming 
 Nitre with the nitrous ley, or with the pure nitrous acid alone. Lime alone 
 does not cryftallize ; with alcalies alone, the cryftals prove fmaller and of a 
 iharper and lefs agreeable tafte than when Lime is added. 
 
 Saltpetre is at prefent prepared and refined in almoft all countries, not only 
 in the Eaft-Indies, but in feveral parts of Europe, as Mufcovy, Poland, Swe- 
 den, Denmark, England, France, Bohemia, Germany. The Nitre produced 
 at different works differs in degree of purity ; it has naturally an admixture of the 
 Sea-falt employed in the compofitions from which it is made : Oftentimes a 
 
 quantity of Alum is fraudulently mixed. It is purified by folution in water, fil- 
 tration and cryftallization : The pure Nitre fhoots firff, the Sea-falt and other 
 heterogeneous matters remaining diffolved : Some add to the folution a little 
 alcaline ley or Quick-lime *, others a fmall portion of Alum, which occafions 
 the cryftals to be larger. For fire-works the Nitre is diffolved in Vinegar, 
 whofe inflammable matter is fuppofed to promote the detonating power of the 
 Nitre. In the arfenal at Paris, Saltpetre is refined to different degrees of pu- 
 rity : Of this manufadture a pretty full account is given by Lemery. 
 
 The purity of Saltpetre is commonly judged from the cryftals being large 
 and long, colourlefs, tranfparent, free from knots or protuberances, and from 
 their crackling when held in the warm hand. Cubical cryftals are a mark 
 either of common Salt itfelf, or at leaft that the nitrous acid is combined with 
 the Alcali of common Salt inftead of a vegetable Alcali. Their crackling or 
 flying about when laid on a burning coal is a more certain mark of Sea-fair, 
 and their fwelling up into blifters after burning, of Alum. Some require the 
 Nitre to burn totally away, and look upon fuch as leaves any refiduum to be 
 .impure ; but the pureft Nitre leaves always a refiduum, though we feldom find 
 much remaining upon the coal, greateft part of it fputtering about and run- 
 ning off. The purity is moft fatisfadtorily determined by rediffolving and 
 •cryftallizing the Nitre, and comparing the firft and laft cryftals together ; and 
 by examining what kind of fpirit they afford. 
 
 Pure Nitre (i.) diffolves in lefs than feven times its weight of water. (2.) It 
 has a cooling tafte, and increafes the coldnefs of water in its diffolution. 
 (3.) It melts with a lefs degree of heat than moft of the other Salts, and flows 
 thin as water. (4.) It bears a melting heat for a confiderable time without 
 lofing any of its acid, but at length parts with a little, as appears from its 
 growing rnoift on expofure to the air, its alcaline principle now prevailing: 
 The whole quantity of the acid however, can fcarcely be expelled, or not 
 without a very long continuance of intenle fires with frequent alternations of 
 cold. (5.) It does not take fire of itfelf how ftrongly foever it is heated, but 
 immediately deflagrates on the contadb of inflammable matter, whether vege- 
 table, animal or mineral. (6.) It does not deflagrate with fluid fubftarces 
 till their aqueous part is evaporated. (7.) It deflagrates with the imperfedt 
 metals and femimetals, diflipates their phlogifton, and changes them into a 
 calx. It is the trueteft of inflammable matters, extricating and burning with 
 the inflammable principle wherever it is to be found. (8.) In the adt of defla- 
 gration 
 
201 
 
 Mineral Salts. 
 
 gration the acid of the Nitre is deftroyed ; the vapours which exhale are uri-N i t r e. 
 nous, and the matter which remains is the fixed alcaline Salt of the Nitre. 
 
 (9.) Inflammable fubftances are incapable of themfelves of burning without 
 air: By the addition of Nitre they burn in vacuo. If the air, however, is fo 
 perfectly exhaufted as that the coaly matter will not catch the fire, the Nitre in 
 fuch cafe will not kindle it. (to.) Nitre froths up greatly in the fire on the 
 admixture of fixed alcaline Salt or Borax, particularly the latter. (1 1.) In di- 
 ftillation its acid arifes in deep red, garnet-coloured vapours. (12.) Though 
 produced by putrefadion, it refills putrefaction the molt powerfully of ail the 
 Saks. It gives a red colour to animal flefh. 
 
 The principal confumption of Nitre is in the making of gunpowder, and inufe3. 
 compofitions for fire- works : For this laffc ufe, the workmen have a commodi- 
 ous method of reducing large quantities into a powder, called Saltpetre meal, 
 by diflfolving it in a little water, evaporating the folution, and keeping the 
 matter conftantly Itirring with a wooden fpatula during the exficcation. This 
 Salt is employed alfo in the refining of metals, in dying, in the compofition of 
 coloured glades, for heightening and calling forth latent colours, for preferving 
 provifions, and fundry other mechanical and ceconomical ufes. The dungs Nitrous Salt 
 which improve the fertility of land, fee m to produce that effedt by virtue o-fin vegetables, 
 the nitrous matter generated from them by the air. Wherever we meet with a whence * 
 true nitrous Salt in vegetables, we may be fure that the plant has grown in a 
 rich dunged field, on nitrous walls, or other nitrous foils; for fuch a Salt is by 
 no means natural to vegetables, though not unfrequently found in them. In 
 fields there are fomctimes lumps of dung left unlpread : The plants which 
 
 grow on thofe fpots fhall be impregnated with a nitrous Salt, whilft others of 
 the famekind, growing in an undunged part in their neighbourhood, fhall have 
 none. We often obferve thefe differences in fumitory, tobacco, particularly 
 its ftalks, the plants which grow on walls and the thatch of houfes, &c. 
 
 There have been many preparations of Nitre contrived for medicinal ufe, but Medicinal 
 pure Nitre itfelfis preferable to them all, and has a better claim to the tide of a preparations, 
 polychreft Salt than any, either of its own preparations or of thofe of other Salts. 
 
 See Stahl’s Menfis martins , de ufu Nitri medico polycbrejio. 
 
 Some diflolve Nitre in vegetable juices, infufions or decoflions, and cry- infuccated. 
 flallize it afrefh : The Nitre thus infuccated as it is called, is diftinguifhed by 
 the name of the plant whofe juice, fsV. has been ufed ; Nitrum rofatum , viola- 
 turn , papaveratum , hordeatum, dzc. Such preparations are at beff unneceffary; 
 for if the Nitre is fuppofed to retain any thing of the vegetable, the advantage 
 expected from thence may be obtained with greater certainty by exhibiting an 
 infufion or other fuitable preparation of the vegetable along with the Nitre, 
 
 When dilfolved in the juices of faline plants, as that of forrel, the Nitre will 
 evidently retain a portion of the eflential fait of the herb, and in this cafe is 
 called Nitrum ejfentificatum : But here alfo it is furely more advi fable to mix the 
 pure effential Salt with a certain determinate quantity of pure Nitre. 
 
 The Nitrum cache Elicum, or Nitrum chalyb'eatum, is a mixture of Nitre, Ar- Chafi bested, 
 canum duplicatum^ and Vitriol of Iron, dilfolved and cryffallized together-— 
 
 Nitrum nitratum, or Draco jortificatus , is made by adding Spirit of Nitre to a Nitrated, 
 folution of Nitre, in the proportion of about half an ounce of the fpirit to an 
 
 D d ounce 
 
20 : 
 
 Mineral Salts. 
 
 Regenerated. 
 
 Sa! prunellse. 
 
 Nit re. ounce of the Salt, or diffolving the Salt in the acid fpirit, and then cryftal- 
 
 lizing. Some cohobate the acid feveral times upon the Nitre Nitrum rege- 
 
 neratum , or ‘Tartarus nitratus, is prepared by faturating Spirit of Nitre with fixt 
 alcaline Salt, and cry ftalli zing the neutralized liquor. The Salt thus prepared 
 is fomewhat fharper than common Nitre: Boiled for fome time in a Tin veffel 
 it fcnfibly corrodes the Tin, an efted never oblerved from common Nitre: By 
 the addition of Lime, or rediffolution in Lime-water, it lofes this acrimony, 
 and becomes indiftinguifhable from pure Nitre. 
 
 Nitrum tabulation , preparatum, fulphuratum , Rotula nitri, Cryjlallus miner alis y 
 Lapis or Sal prunelle, is made by melting a quantity of Nitre in a crucible, and 
 injecting upon it, when in thin fufion, fome flowers of Sulphur, in the propor- 
 tion of about a dram to an ounce of Nitre : When the deflagration is over, the 
 fluid matter may betaken up with a tobacco-pipe or other like inftrument, and 
 dropt upon a Copper plate fo as to form it into little cakes. The Sulphur 
 fhould be injeded by a fmall quantity at a time: Some ufe Sulphur in the 
 mafs, and throw in a whole piece at once, but I have feen dangerous confe- 
 
 quences from this pradice In this procefs, the acid of the Sulphur expells a 
 
 partof that of the Nitre, and unites with a proportionable quantity of the Al- 
 cali into a vitriolated Tartar ; fo that the preparation is no other than a mixture 
 of Nitre and vitriolated Tartar in uncertain proportions, different operators em- 
 ploying different quantities of Sulphur. Where a mixture of thefe Salts is 
 wanted, the rational prefcriber will never dired fuch a precarious compofition, 
 whilft the two Salts are to be had feparately, and may be readily mixed toge- 
 ther in fuch proportions as he (hall think fit. 
 
 Arcanum du- The Arcanum duplicatum , Sal catholicum , fapientia , antifebrile, de duobus , &c. 
 plicamm. is compofed of the Alcali of Nitre and the acid of Vitriol, remaining after the 
 diftillation of the nitrous fpirit with Vitriol or its acid. (See page 205.) The 
 alcaline balls of Nitre differs from the common alcaline Salt made from Tar- 
 tar, only in having a fmall admixture of calcareous earth. Wej have formerly 
 feen that the acid of Vitriol forms with this earth a concrete not diffoluble in 
 water, and which confequently cannot be retained in the preparation ; fo that 
 the Arcanum duplicatum appears from its compofition, as well as from experi- 
 ments made upon it, to be entirely the fame with vitriolated Tartar. 
 
 A combination of the Alcali of Nitre with the acid of Sulphur is commonly 
 called, from ignorance of its real nature, Sal polychrejlum. This is prepared 
 from equal parts ofNitre and flowers of Sulphur mixed together, injeded by 
 degrees into a red-hot crucible, kept in the fire for fome time, when grown 
 cold elixated with water, filtered, evaporated and cryftallized. A Salt pre- 
 pared in the fame manner from equal parts ofNitre, Sulphur, and cryftals of 
 Tartar, is faid by Senac to be the Sal polychreft of Seignette. Monf. Petit 
 has given feveral curious experiments of the vegetation or efflorefcences of 
 thefe kinds of Salts in their cryftallizatfon. 
 
 Antimoniated The Nitrum antbnoniatum or Anadynum miner ale, is a neutral Salt obtained by 
 Nitre. cryftallizing the firft walkings of diaphoretic Antimony (pag. 137). It is fo 
 extremely uncertain in quality, that the phyfician can never truft to it, being 
 fometimes an Arcanum duplicatum or Sal polychreft, fometimes a mixture of 
 that Salt with unchanged Nitre, impregnated more or lefs with the reguline 
 
 part 
 
 Sal poly- 
 chreft. 
 
Mineral Salts, 203 
 
 part of the Antimony. We may readily diffinguifh its containing Nitre, by N itre, 
 its deflagrating on burning coals. This Nitre may be diftinguifhed from pure v. — — v— = 
 Nitre by grinding a little of it in a mortar with Alum or Vitriol, when the 
 antimoniated Nitre will immediately yield a fmell of Aqua fords, which 
 the common Nitre does not ; or by diffblving it in water, and adding ftrong 
 Spirit of Vitriol, which will precipitate a white reguline powder from the anti- 
 moniated Nitre, but throw down nothing from the pure. 
 
 The Nilr'um fixum is the fixt alcalineSalt of Nitre, freed from its acid by Fixed Nitre, 
 deflagration with inflammable matters, and purified by folution in water, filtra- 
 tion, and evaporation. As vegetable coals deflagrate with Nitre more readily 
 and more freely than the moifter animal fats or other like matters, thofe are 
 made choice of for this operation. Some melt the Nitre firftin a crucible, and 
 gradually injeft upon it powdered Charcoal, till a frefh addition occafions no 
 further deflagration upon ftirring the matter: Others invert the procedure, in- 
 jecting the Nitre upon the ignited Charcoal ; and others grind both the ingre- 
 dients together, and injedt the mixture into a red-hot crucible : This laid me- 
 thod feems to be the beft. The perfedt alcalization of the Salt depends chiefly 
 on the due proportion of the Charcoal to the Nitre ; for if this is not hit, a 
 part of the Nitre will remain unchanged. Three parts of Nitre are com- 
 monly diredded to one of Charcoal ; but if the Charcoal is good, fix or feven 
 parts of Nitre will not be more than fuffkient, and the Nitre will be more per- 
 fectly alcalized than if its proportion was lefs. It is very difficult to deftroy 
 the acid by one operation fo effectually as that the remaining Salt fhall not 
 yield red nitrous vapours on the affufion of Oil of Vitriol: Hence Hoffman 
 was led to affirm, that fixt Nitre differs from the common fixed Alcalies. When 
 fully alcalized, it is in all refpedts the fame, and yields like them, not red but 
 white fumes with the vitriolic acid. A part of the acid of the Nitre feems, in 
 the deflagration, not to be diffipated or volatilized, but fixed and converted into 
 an Alcali : Sixteen ounces of pure cryftalline Nitre confift of about eight ounces 
 of water, four ounces of pure acid, and four of Alcali : If this quantity of the 
 Salt be deflagrated with three or four ounces of Charcoal, which lcarcely yield 
 four or five grains of Alcali, eight, ten, and if the operation is caref ully per- 
 formed, even twelve ounces of pure alcaline Salt will be obtained. 
 
 Nitre deflagrated in the fame manner with Tartar, is reduced like wife into Extempora- 
 an alcalineSalt, which here receives an addition from the Alcali furnifhed byneousSalt of 
 the Tartar. When the Nitre and Tartar are taken in equal quantities, nearly Tartar » 
 all the Nitre is alcalized, and a white Salt remains, called extemporaneous Salt 
 of Tartar : If the quantity of the Nitre is double to that of the Tartar, great 
 part of the Nitre continues undeffroyed : On the other hand, if the quantity 
 of Tartar is double or treble to that of the Nitre, all the Nitre is detlroyed or 
 alcalized, but great part of the Tartar is converted only into a black coal, the 
 Nitre being infufficient to burn out all its inflammable matter. This laft 
 compound is the common reductive Flux for metals among the chemifts, gold- 
 fimiths, affayers, C?r. and diftinguifhed from its colour by the name of black Black flua, 
 flux: The coal of the Tartar fupplies the inflammable principle neceflary for 
 the revival of metallic calces ; and the Alcali furnifhed by the Nitre promotes 
 
 D d 2 their 
 
204 Mineral Salts. 
 
 Nitre, their fufion. Both the black Flux and the white Salt are commonly prepared, 
 — 'by grinding the Nitre and Tartar leparately into powder, then mixing them 
 together, and fetting them on fire in an Iron mortar, without applying any 
 other heat than that which arifes from their own deflagration. It is remarkable 
 in this procefs, that though both the ingredients leparately yield an acid fpirit, 
 yet here no marks of acid are to be perceived, the vapour which exhales being 
 of the urinous kind ; and that though Tartar, when calcined by itfelf to w hi te- 
 nets, leaves on being difiolved in water a very confiderable quantity of earth, 
 yet when thus burnt white by Nitre it almoit totally dififolves, leaving fcarcely 
 any earth at all. The elder Geoffroy feems to claim the difcovery of a volatile 
 urinous Spirit being produced from Nitre and Tartar, in the French Memoirs 
 for the year 1 717; but the fame obfervation was made by Stahl thirty years 
 before. 
 
 Cauftic Nitre. Nitre is alcalized likewife by deflagration with metallic fubftances : By the 
 martial Regulus of Antimony it is rendered not only alcaline, but exceffively 
 cauflic, whence its nam zNitrum caujlicum. A like effedt is produced alfo, but 
 in a lower degree, by filings of Iron, by Tin, and other mineral fubftances, 
 whofe phlogifton is fixed or intimately combined in the compofition of thefub- 
 jedt. Schroder reports that Nitre is alcalized by Quick-lime, but on trial this 
 did not happen. For preparing the Nitrum caujlicum , nothing more is required 
 than to mix the Nitre and martial Regulus in fine powder, and cement them 
 for a time together. 
 
 Mao-nefia Magnefta alba (fo called in diftindtion from the plain Magnefia orManganefe, 
 
 alba. which is employed in the making of Glafs) is a white very fubtile powder, 
 
 prepared from the mother-ley, or the liquor which remains after the firft cry- 
 ftallization of rough Nitre. It was introduced as a medicine about fifty years 
 ago, by Count di Palma at Rome, and continued a very lucrative fecret. 
 Sundry ocher preparations dilferent in colour, yellow, brown, and violet Mag- 
 nefia> were likewife vended in oppofitionto it This celebrated medicine ap- 
 
 pears to be no other than a calcareous earth impregnated with a minute portion 
 of the nitrous and marine acids, and to have very little claim to the virtues 
 commonly afcribed to it. That the mother- ley contains thofe acids is evident 
 from its yielding, when exficcated and diftilled with Oil of Vitriol, an Aqua 
 regis. The matter diffolved in them appears to be chiefly the Lime that had 
 been added in the extraction of the Nitre : If an alcaline Salt has been em- 
 ployed for this purpofe without Lime, no Magnefia will be obtainable from the 
 mother-ley. If the mother- ley is infpiffated to drynefs, and then calcined, 
 greateft part of the acids is expelled: On edulcorating the calx with water, 
 the fmall portion of Nitre or Sea-falt that might have been retained is walked 
 off, and little other is left than the mere calcareous earth : This is the cele- 
 brated Magnefia. If common Quick-lime, flaked, dried, and ground into 
 fine powder, be moiitened with a little Spirit of Salt and Spirit of Nitre, then 
 calcined and edulcorated, the fame Magnefia will be obtained as that produced 
 from the mother-ley. Hoffman proposes a more expeditious and commodious 
 method of preparing the Magnefia from the mother-ley than that above-men- 
 tioned, by precipitation with Oil of Vitriol., Oil of Tartar per deliquium, or 
 s Spins 
 
Mineral Salts. 205 
 
 Spirit of Sal ammoniac j the Precipitates however* obtained by thefc three li- N i r r e. 
 quors, will not be entirely the fame(/). 
 
 The Terra foliata nitri is made from alcalized or fixed Nitre faturated with Terra f 0 ]j aCa 
 Vinegar, in the fame manner as the terra foliata tartari from Salt of Tartar — nitri, Uc. 
 The Nitnim ammoniacale fixiim of Wedelius is prepared by inject ing one part of 
 powdered Sal ammoniac upon four of melted Nitre — A mixture ol four ounces 
 of Nitre, a dram and a half of Borax, a dram and a half of Sal ammoniac, and 
 a fcruple of flowers of Sulphur injected gradually into a red-hot crucible, is 
 called Nitrwn antifebrile . 
 
 Having now gone through the folid preparations of Nitre we proceed to the Spirit of 
 fluid, the principal of which is the acid fpirit. Nitre committed to diftilla- Nitre, 
 tion by itfelf flows in the retort like water, and does not give over any fpirit. 
 
 The ancient chemifls, fuppofing the extrication of the acid to be prevented by 
 the fufion of the Salt, mixed with it certain earthy matters to divide or difeon- 
 tinue its particles, and thus prevent its fufion. To one pound of Nitre they took 
 fix or eight pounds or more of red Bole or Loam, diflolved the Nitre in water, 
 worked up the powdered earth with this folution, and formed the mixture into 
 balls about the fize of pigeons eggs : Thefe were dried in a warm place, put into 
 earthen retorts, and diftilled in a reverberatory furnace. An acid fpirit now 
 arofe, but commonly weak and in fmall quantity : On elixating the refiduum 
 with water, it was found that only a little of the Nitre had given out its acid, 
 the greateft part being recoverable in its original form, and having luffered no 
 refolution or feparation of its principles. The Nitre thus recovered, diftilled 
 with frefh earth, yields more fpirit ; and the Nitre, which then remains un- 
 changed, treated again in the fame manner affords more, till the whole quan- 
 tity of the Salt is thus refolved. The earth, on the other hand, which has 
 once been ufed, though perfedfly freed by water from all remains of the Salt, 
 if mixed a fecond time with Nitre, will never extricate any more of its acid ; a 
 proof that the expulfion of the acid depends not upon the divifion or difeonri- 
 nuation of the Nitre, for the earth divides it now as effedfually as at firft, but 
 on lb me particular matter in the earth, which it lofes in the firft operation. 
 
 The white earths, as Chalk, Lime, calcined bones, tobacco-pipe clay, Uc. 
 extricate no acid from Nitre even on the firft time of ufing. 
 
 Stahl was the firft who difeovered the true theory of this operation. All the 
 earths which extricate the acid of Nitre contain vitriolic acid ; and it is on this 
 acid that the effedt wholly depends. Hence Vitriol itfelf, as containing much 
 
 more 
 
 (/) Magnefia alba.'] Magnefia alba differs 
 from calcareous earths in two remarkable 
 properties. One is, that it is not con- 
 vertible by fire into Quicklime, the true 
 criterion of earths of the calcareous kind : 
 The other, that it diffolves readily in the 
 vitriolic acid, into a limpid, bitter, purga- 
 tive liquor, whereas calcareous earths con- 
 crete with that acid into an infipid and in- 
 difl’oluble felenites, and all the other earths 
 that diffolve in it form auftere ftyptic com- 
 pounds. As confiderable quantities of Lime 
 
 are mixed with nitrous earths previoufly to 
 the elixation of the Nitre, the earth ob- 
 tained from the mother-ley may often con- 
 tain a portion of calcareous earth, or even 
 confift almoft wholly of that earth ; whence 
 probably our author was milled into the opi- 
 nion of this earth being no other than the 
 calcareous. The earth which makes the 
 bafis of the purging Salts of mineral waters, 
 and the incinerated earths of vegetables, 
 are a pure Magnefia. See page 190. 
 
2o6 Mineral Salts. 
 
 Nitre. more of the acid, is employed to far greater advantage. If equal parts of 
 Nitre and of green Vitriol calcined to yellownefs be committed to diftillation, 
 
 N the whole of the nitrous acid will arife. It has been generally fuppofed, that 
 the acid of the Vitriol comes over in this proceis along with that of the Nitre-, 
 
 Aqua fortis. and hence the diftilled fpirit is called, not Spirit oi Nitre, but Aqua fortis. 
 
 This however is by no means the cafe, the fpirit, if the ingredients have been 
 duly proportioned, being purely nitrous : All the vitriolic acid remains united 
 with the alcaline bafis of the Nitre, and forms therewith the neutral Salt called 
 Arcanum duplicatum , or vitriolated Tartar. It is a diftinguifhing character of 
 the vitriolic acid iq dillodge both the nitrous and marine from any kind of al- 
 caline Salt, and to unite with Alcali in their place. 
 
 The makers of Aqua fortis in Holland ufe for the diftilling veffel a large 
 Iron pot with an earthen head and receiver, and keep the receiver cool by a 
 
 conftant application of cold water They commonly employ rough Saltpetre 
 
 without purification ; and as Saltpetre in this ftate almoft always participates of 
 Sea- fait, the nitrous fpirit receives from thence a proportionable admixture of 
 marine acid. The Eaft-India Saltpetre is feldom free from pepper corns, 
 draws and other vegetable matters, by which the Aqua fortis is further fouled. 
 When uncalcined Vitriol is ufed, fomepartof its volatile phlegmatic acid, ha- 
 ftily extricated at firft, will arife without adling upon the Nitre-, and if the Vi- 
 triol is taken in a larger proportion than the nitrous Alcali can faturate, a part 
 of its concentrated acid will diftil towards the end of the procefs. Hence Aqua 
 fortis as commonly prepared is very feldom pure, as is well known to the re- 
 finers, who feparate Silver from Gold by means of this acid Pure Aqua 
 
 fortis or Spirit of Nitre perfectly diflolves Silver into a colourlefs tranfparent 
 liquor: A mod minute portion of the marine or vitriolic acids added to this 
 folution, renders it milky, extricating a part of the Silver, which on (landing 
 falls to the bottom along with the extraneous acid. Hence we are furnifhed 
 with a fure method of diftinguifhing whether Aqua fortis participates of thofe 
 acids, and of purifying it from them. A little folution of Silver made in the 
 pure nitrous acid, is to be dropt into that which is to be examined : If any 
 milkinefs orcloudinefs enfues, we may be certain that the Aqua fortis is im- 
 pure: If on (landing till the milkinefs has fubfided, another drop of the folu- 
 tion occafions no frefh cloudinefs, we may be equally fure that the impurities 
 are now feparated. Solution of Mercury likewile precipitates the marine acid 
 from Aqua fortis in the fame manner. Thefe experiments are a further proof 
 that perfect Aqua fortis, fuch as will diffolve Silver, is no other than a pure 
 Spirit of Nitre, fince the nitrous acid mixed with either of the others will not 
 diffolve it. 
 
 Some diftil the nitrous fpirit with Alum inftead of Vitriol, taking two parts 
 of burnt Alum to one of Saltpetre. Others have ufed the dilute acid fpirits 
 previoufly extrafted from Vitriol or Alum : Of thefe, no proportions can be 
 fixed as the ipirits differ greatly in degree of ftrength : If the nitrous fpirit ob-, 
 tained by this means is found to participate of the vitriolic acid, it is purified 
 by drawing it over again from a little frefh Nitre, which will retain that acid •, 
 if it proves too phlegmatic, it is concentrated by diftillation without addition, 
 the watery part arifing firft, and the ftronger acid remaining behind. The 
 
 Spirit 
 
Miner, al Salts. 2G7 
 
 Spirit of Nitre prepared both by Alum and by the pure vitriolic acid, emits Nitr e. 
 red fumes in the air like that obtained by means of Vitriol ; a proof that thefe — v — -> 
 
 vapours are not owing, asLemery fuppofes them to be, to a Sulphur imbibed 
 from the Vitriol, or to any metallic impregnation. 
 
 The ftrongeft Spirit of Nitre is obtained moft commodioufly by means of the 
 concentrated Oil of Vitriol. Pure dry Nitre reduced into powder, is put into 
 a tubulated retort placed in Sand, a large receiver clofely luted on, and forne 
 Oil of Vitriol poured in by a little at a time, through the tube oi the retort, 
 which is to be clofely ftopt after each addition. A part of the nitrous acid will 
 arife without the application of any heat: After the fpontaneous vapours have 
 ceafed, the lire is to be augmented by degrees till nothing more will come over. 
 
 This fpirit is extremely ftrong, fubtile and volatile, and requires to be well fe- 
 cured from the air, otherwife its more active parts will foon be diftipated. It 
 is diftinguifhed by the names of Spiritus nitri concentratus , Volatilis , Fumans 
 Glauberi , from its inventor Glauber, though Boyle alfo claims the difcovery ; 
 and Flammificus or Inflummans , from its fetting fome effential oils on fire when 
 haftily mixed with them. Hoffman has given fome experiments of this kind 
 in his Obfervationes -phyfico-chymica j and the younger Geoffroy in the French 
 Memoirs. 
 
 Five parts of powdered Nitre and three of powdered Sulphur, mixed together ciyffus. 
 and injected by a little at a time into a tubulated retort furnifhed wfith a reci- 
 pient, yield a mixed acid fpirit, compofed of the nitrous and vitriolic acids. This 
 is called Clyjfus ; and when Antimony is ufed inftead of Sulphur, Clyjfus anti- 
 monii. They are both of them very infignificant preparations, and not worth 
 the making. The vitriolic acid may be feparated, and the fpirit rendered 
 purely nitrous by drawing it over from a little frelh Nitre. 
 
 In all the foregoing diftillations, the nitrous acid is expelled from its a lea line Nitrons fpirir 
 bafis by the more powerful vitriolic. There are methods of extricating the by vitriika- 
 nitrous without the intervention of that acid: If Nitre and fand be mixed tlon * 
 together and urged with a ftrong fire, the Alcali will let go the acid, unite with 
 the fand and melt with it into Glafs. Arfenic alfo expells the acid of Saltpetre : Blue fpirit of 
 The fpirit obtained by means of this concrete differs furprizingly from all Nure ’ 
 the others in an exceflive degree of volatility, and a deep blue colour. See 
 page 142. 
 
 CLASS III. 
 
 Marine acid and its combinations, 
 
 T H E marine acid, fo called from its being diffufed through the waters ofjyf^ r i n e 
 the ocean, and making a conftituent part of the neutral Salt fo plenti- Acid. 
 fully extracted from them for culinary ufes, is fuppofed by the chemifts to be i — _i 
 an offspring of the primordial or vitriolic acid, and to confift of that acid com- 
 bined with an inflammable and a mercurial or arfenical principle. 
 
 This acid is ftronger than any of thofe of the vegetable or animal kingdom. General pro- 
 but weaker than the vitriolic or the nitrous, diflodging the former from alca-P erties ’ 
 
 7 OO 
 
 line Salts and earths, but being itfelf diflodged from them by both the latter. 
 
 In 
 
208 
 
 Mineral Salt 
 
 s. 
 
 M arine In the mod concentrated date in which we can eafily colled it from other bo- 
 il c i n. dies, it contains about feven drams of water to one of pure acid. It is in part 
 diffipated by the a&ionofthe air in pungent vapours, not of a red colour like 
 thofe of the nitrous acid, but white. It ariles in diftillation alfo in white 
 fumes, which condenfe upon the Tides of the recipient in ftrias like Spirit of 
 Wine. 
 
 As a men- 
 ilruumol me' 
 tals. 
 
 Liquefcibility 
 of its combi- 
 nation with 
 metals. 
 
 Volatilizes 
 
 metals. 
 
 Article I. 
 
 Combination of the marine acid with metallic bodies. 
 
 H E marine acid eafily diffolves Zinc, Iron, and Copper. It ads more 
 difficultly on Tin, and fcarcely ads at all in its liquid ftate, though 
 shifted by a confiderable heat, upon Silver, Mercury, Lead, or Regulus of 
 Antimony. There are means, however, of combining it with all metallic 
 bodies : Thus, when the pure acid is abforbed from the phlegm by fixed alca- 
 line Salts, and the phlegm evaporated, if the dry Salt be committed to the fire 
 in a proper veffel, with the addition of vitriolic acid, the marine acid will be 
 extricated from the Alcali in highly concentrated vapours, by which all the 
 metals except Gold are diffolved or corroded. It diffolves Gold by the affift- 
 
 ance of the nitrous acid, in its liquid ftate (ttt) It diffolves metallic bodies 
 
 when calcined, or deprived of their phlogifton by fire, in which ftate the ni- 
 trous acid has no effedt upon them. The metallic matter, from which the co- 
 loured earths and ftones receive their colour, is likewifeextradted by this acid. 
 
 All the combinations of metals with this acid are eafy of fufion in the fire. 
 There are few which concrete into a cryftalline form : All but thofe of Silver, 
 Mercury and Lead, if exficcated by heat, imbibe moifture from the air, and 
 run into a liquid ftate. The compound which it forms with Silver is not dif- 
 foluble in water •, that with Lead is fcarcely fo, and with Mercury difficultly: 
 With Regulus of Antimony it forms a butyraceous or liquid matter, from which 
 the metallic part is feparated and thrown to the bottom upon diluting it with 
 water. Its combinations with mofl: of the other metallic fubftances are eafy 
 of folution, not only in water but in rectified Spirit of Wine. 
 
 The marine acid when combined with metals, very ftrongly adheres to them, 
 fo as not to be expelled by any degree of fire : In a ftrong fire, it either volati- 
 lizes or carries them through the crucible, but never parts from them without 
 the intervention of fome other matter. Gold itfelf is fo far fubtilized and vo- 
 latilized by this acid, as to fublime and d i ft i 1 over the helm. Silver and Lead 
 are reduced by it into concretes fufible as wax, femitraniparent as horn, and fo 
 volatile that by a moderate fire they may be all driven up the chimney. Bif- 
 muth and Regulus of Antimony diftil with it in a butyraceous form, and Tin 
 in that of a fluid fmokingfpirit. Iron fublimes with it into yellow Gowers. 
 
 (m) Dijfclves Gold.] The marine acid dif- 
 folves Gold alfo without the affiftance of 
 any other acid. If the Gold is melted with 
 Tin or other imperfedt metals, and the mix- 
 ture calcined, or if the Gold is reduced into 
 
 Though" 
 
 the form of a calx, this acid by moderate 
 digeftion, will perfectly, though fparingly, 
 diffolve it, and keep it permanently fuf- 
 pended. See page 33. 
 
Mineral Salts. 209 
 
 Though the marine is weaker than either of the other mineral acids, it has a M a r i n e 
 greater attra&ion to fome of the metals, particularly the white ones, to molt of Acid. 
 which it difcovers a particular affinity : Thus Silver, Mercury, Lead, it preci- 
 pitates from their folutions made in other acids ; but on Gold, Copper or Iron ™ 
 
 it has no fuch effett. tals. 
 
 The metals which it thus abforbs from every other acid, are not thofe to 
 which it difcovers the greateft appetite of union when no other acid intervenes : 
 
 3n this circumftance it will unite with Copper, Iron, or Zinc, in preference to 
 any of the other metallic bodies. When combined with Mercury, if Silver be 
 added to the compound and a moderate fire applied, it will let the Mercury go 
 and corrode the Silver. If this compound be melted with Lead, the acid will 
 be transferred into the Lead, and leave the Silver revived into its metallic 
 form. It will quit the Lead for Regulus of Antimony or Tin ; and either of 
 thefe for Copper, which it diffolves into a green liquor. If Iron be added to 
 this folution, the acid will let the Copper fall, and diffolve the Iron in its 
 
 place ; and in like manner it will part from the Iron to diffolve Zinc Such 
 
 are the general laws of its affinity ; but there are circumftances in which it re- 
 cedes from them. When Sea-falt and Vitriol of Iron are mixed toge- 
 ther and committed to the fire, the vitriolic acid forced out from its metal by 
 the heat, extricates the acid of the Sea-falt, and this laft unites with the Iron 
 which the other has forfaken : So far the general laws of affinity obtain. The 
 exception is, that if Quickfilver be added to this mixture, the marine acid, 
 inftead of uniting with the Iron will unite with the Mercury and yet, when 
 combined with the Mercury, it will forfake that to unite with Iron The 
 event is the fame when Vitriol of Copper is fubftituted to Vitriol of Iron, or 
 Regulus of Antimony to Quickfilver. 
 
 Article II. 
 
 Combination of the marine acid with akaline Salts.. 
 
 I. COMMON SALT. 
 
 T he common alimentary Salt called emphatically Salt without any epi-Co M.MON 
 thet, is fuppofed by fome to be the Sal indum of the ancients : But the Salt. 
 accounts which the ancients have given of the Sal indum are evidently repug- < - — » 
 
 nant to this opinion : They defcribe it as being in colour like Salt,, and in tatle 
 fweet as honey, from whence it plainly appears to have been no other than our 
 fugar, the name Saccharum or Zuccharum being of much later date. 
 
 Common Salt is found either diffolved in the water of the ocean, or in thofe Different, 
 of certain fprings, or in a folid form in the bowels of the earth; whence the kinds > 
 names Sal marinum or Sea-falt, Sal fontaniim or fpring Salt, and Sal foffile or 
 foffile Salt: This laft is called alfo, from its being found in hard tranfparent 
 bright maffes like Cryftal, Sal gemma. All the forts are entirely natural Salts, 
 art doing no more than to extradl them from the waters, or purify them from 
 the heterogeneous matters with which they are intermixed ; whilft Nitre, Alum, 
 
 E e Vitriol,. 
 
210 
 
 Mineral Salts; 
 
 Com mon Vitriol, and other mineral Saks owe to art, in good meafure, their original 
 
 r> - - ^ 
 
 Salt, 
 
 which firft 
 produced. 
 
 water. 
 
 production. 
 
 It has been difputed whether the fea or the fofiile Salt were created firft ; 
 fome fuppofing the fofiile Salt to have proceeded from the fea- water left in ca- 
 verns of the earth at the time of the deluge-, and others, that the fea-water 
 became faiine only at that period, by dififolving the fofiile Salt. It is probable 
 that both forts were created in the beginning : The immenfe beds of rock Sait 
 met with in the earth have no appearance oi their having been left there by the 
 evaporation of water : And on the other hand, that the fea was originally 
 
 faiine may be judged from the Mofaic account of the creation -, whales and 
 other fea fifhes were created on the fifth day, and it is not to be fuppofed that 
 thefe could fubfift without Salt to the time of the flood. 
 
 Quantity of Sea-water contains different proportions of Salt in different climates, not 
 Salt in Sea- en ti re ly, as fome have imagined, from its being in fome places more diluted 
 than in others by frefli rivers running into it; but principally from the greater 
 or lefs heat of the climate, and proportionable evaporation of the aqueous parts. 
 A pound of fea-water in the northern part of the Baltic, particularly in the 
 Sinus Botbnicus , yields fcarcely a quarter of an ounce of Salt : Further fouth, 
 from the mouth of the Elbe to Holland, and in the Britifh channel, a pound 
 yields an ounce : In the Mediterranean and Spanifli feas, the fame quantity of 
 water holds two ounces, and probably, towards the Line, the proportion of 
 Salt will be found greater. Boyle obferves, that the water at the bottom of 
 the fea is more faiine than at the furface. 
 
 The bed Sea-falt and the greatefl quantities, are prepared in Spain and Por- 
 tugal, as at Almahada, near Cadiz, St. Lucar, Malaga, St. Ubes. Confider- 
 how prepared. a kj e q Uant i t i es are ma de alfo in France, and the Englifh have attempted to 
 eftablifh a Salt-work at Minorca. The general method of feparating the Salt 
 is by evaporating the water; and the advantageoufnefs of the manufacture de- 
 pends upon the effecting of this without the expence of fuel. For this pur- 
 pofe, choice is made of a clayie ground near the fhore, fo fituated as that the 
 fea-water may be occafionally let in or out by proper canals and fluices : The 
 ground being overflowed in the beginning of fummer, to a fmall depth, the 
 water gradually exhales by the heat of the fun, and leaves the Salt behind in a 
 cryftalline form. An account of the Salt-works in France may be feen in Le- 
 mery (#). The impure blackifli-grey Salt thus obtained is exported from Spain 
 
 and 
 
 Bay Salt, 
 where and 
 
 (») Salt from the evaporation of fea-water 
 hy the funs heat.] Dr. Brownrigg propofes a 
 fimilar procefs in the Britifh dominions. He 
 fhews, that commonly almoft twice as much 
 water falls annually on the weftern as on 
 the eaftern coafts of England ; that in Lan- 
 cafhire, there does not fall in May, June, 
 July, and Auguft, above one third the 
 quantity that falls during the reft of the 
 year ; that in thefe months, at leaft thirty 
 inches will exhale, and only ten inches 
 fall; that in exceeding hot weather, an 
 
 inch will evaporate in twenty-four hours ; 
 that on the evaporation of fixteen inches of 
 fea-water, there will remain one hundred 
 and twenty-eight grains of Salt on every 
 fquareinch, and 104544 pounds on an acre. 
 He direfts the ponds to be made in a row 
 from Eaft to Weft, and fitted with covers 
 of fail-cloth ftretched on frames and painted 
 white : Thefe ferve both to keep out rain, 
 and in dry weather to refleCt the fun’s heat. 
 The brine in the firft large refervoir may be 
 occafionally forced up by afire engine, with 
 
 a di- 
 
21 1 
 
 Mineral Salts. 
 
 and Portugal, to England, Holland, Sweden, and many other parts oftheCoMMON 
 world, uhder the name of Bay-falt: This is refined by the Englifii and Dutch, Salt. 
 
 by folution in a little water, clarification commonly with fome oxe’s blood, and / 
 
 evaporation continued till the Salt forms into grains : In this refined ftate like- 
 wife it proves an article of extenfive commerce. The Salt made in France is 
 confumed chiefly in France itfelf, and without purification, fuch an extravagant 
 duty being laid upon it, that people of middling circumftances cannot afford a 
 tefined Salt. 
 
 The more northern nations, Denmark, Norway, Sweden, &V. where the Sea-water 
 fun’s heat is infufficient for the preparation of Sea-fak by the method above- concentrated 
 mentioned, might avail themfelves of their natural cold, by which greatefl part b f coI(i - 
 of the fuperfiuous water will freeze, leaving a faturated faline folution, from 
 which the Salt may be feparated with little expence of fire. 
 
 The point in viewinthele operations, is, to diflipate the water and preferve 
 the Salt : It were to be wilTied we could equally feparate the Salt and preferve 
 
 the 
 
 a di verger, to make it fall in drops. The 
 expence of this apparatus, he obferves, will 
 be much lefs than that of the common falt- 
 ern, excluftve of the fuel, which often cofts 
 more than two-thirds the value of the Salt. 
 
 At Lemington, fea-water is concentrated 
 by the fun’s heat fo advantageoufly, that 
 though afterwards boiled with Newcaftle 
 coal, the Salt can be afforded cheaper than 
 that made in the neighbourhood of New- 
 caftle itfelf, where the fuel is not above one 
 fourth the price. 
 
 i Salt from fea-waier by fire.'] The brine is 
 boiled down in large pans made of Iron 
 plates, joined with nails, and cemented with 
 Lime. From a pan of about 1305 gallons 
 are drawn every day fifteen or twenty bufhels 
 of Salt, each bufhel containing fifty-fix 
 pounds. In Northumberland and Durham 
 there are upwards of two hundred pans at 
 work, in which are annually prepared ele- 
 ven or twelve thoufand tuns of Salt. 
 
 To the brine juft warm are added the 
 whites of three eggs, or a little ox blood, 
 mixed with two or three gallons of fea- 
 water. As the heat increafes, a black fcum 
 arifes, which is raked off, and the liquor 
 now perfectly clear, kept ftrongly boiling : 
 An earth called fcratch, fubfides into fmall 
 pans placed for that purpofe in the corners 
 of the boilers, where the motion is moft 
 gentle. When cryftals begin to form on 
 the furface, the pan is filled up, clarified 
 afrefh, and this repeated four times. When 
 the Salt now begins to cryftallize, the fire is 
 
 flackened, and the liquor kept only fimmer- 
 ing during the granulation. After the Sea- 
 falt has cryftallized, a bitter liquor remains, 
 which on further evaporation yields the bit- 
 ter purging Salt, page 189. 
 
 Common Salt has one remarkable pro- 
 perty, in which it differs from all the other 
 neutral Salts. It diffolves almoft as plen- 
 tifully in cold as in hot water j if water 
 be fully faturated with it when boiling hot, 
 fcarcely any of the Salt feparates or cryftal- 
 lizes upon the liquor’s growing cold. The 
 Salt concretes only in proportion as the 
 water evaporates, and hence the neceffity of 
 keeping up the heat during the whole time 
 of the cryftallization .... If the procefs is 
 too long continued, the bitter Salt cryftal- 
 lizes along with the culinary Salt. We fel- 
 dom meet with any Sea-falt entirely free 
 from the bitter one : Hence the earthy mat- 
 ter, which folutions of Sea-falt depofite upon 
 the addition of alcalies, and which fome 
 have erroneoufiy looked upon as one of the 
 conftituent parts of the Sea-falt itfelf. 
 
 There is another fingular property of 
 common Salt, its parting with a confider- 
 able quantity of its acid, on boiling down, 
 whether in open or clofe veffels, a faturated 
 folution of it to drynefs. Hence the acid 
 which arifes in the diftillation of fea-water, 
 efpecially towards the end of the procefs 5 
 and hence the alcalefcent quality of Sea- 
 falt cryftallized by too ftrong a beat, its 
 difpofition to liquefy in the air, its weaknefs 
 and unfitnefs for preferring provifions. 
 e 2 
 
2 I 2 
 
 Mineral Salts. 
 
 Common the water, fo as to obtain from the fea a fweet water, fit for drinking and the 
 Salt, other ufes of life. Sundry methods have been propofed for this purpofe, but 
 — v — none have hitherto fully fucceeded : I have feen many machines and models of 
 machines, which anfwered in fome refpe&s, but failed in others. SttJVater. 
 
 Bittern. The mother-ley of Sea-falt, or the liquor which remains after the purifica- 
 
 tion and cryftallization, is employed in England for making a purging bitter 
 Salt, which proves fimilar in quality to the Salt obtained from the Epfom 
 waters, and is commonly fold under its name. The ley is boiled down to 
 a certain pitch, then filtered and infpififated, the dry matter calcined, re- 
 difiolved, and cryftallized. (See page 1 89.) If the mother-ley be infpiffated, 
 and diftilled with vitriolic additions, a Spirit of Salt is obtained. 
 
 Sal gem. The foftile Salt or Sal gem is found in feveral parts of Europe, as in Poland, 
 
 in Spain, particularly in Catalonia, in Mufcovy, in Calabria, in Tranlylvania, 
 and atStowerin the upper Hungary. Some of thefe Salt mines are of amaz- 
 ing magnitude : The fingle mine of Cracow in Poland, near Wielizka and 
 Bochna, is computed to hold Salt enough to fuffice the whole world for many 
 thoufand years. There are houfes, chapels, &c. under ground, all built of 
 Salt or the Salt ftones. The fofiil is cut and turned into pillars, altars, cruci- 
 fixes, images, &V. oftentimes it is naturally cryftallized into very curious 
 figures. MafTes are brought up to day, weighing from twenty to thirty hun- 
 dred weight. The pure faline maftes are called St one -fait , the harder and more 
 ftony, Salt-Jlones. Pieces of thefe laft are commonly put into cow-ftalls for 
 the cattle to lick, as they hold longer than the Salt. In Poland, Tranfylvania 
 and Hungary, the mineral is commonly white or greyifh : In Catalonia, it is 
 often reddifh, bluifh, and of various other colours. The pure cryltalline 
 pieces are employed for the common purpofes of Salt in their natural ftate : 
 The more impure and crumbly are purified by folution in water, filtration and 
 cryftallization : They do not now concrete into maftes of the original fize, 
 though the cryftals arefomewhat larger than thofe of fea or Spring- fait. 
 
 Spring- fait. The Spring-falt is the fort generally made ufe of among us, and underftood 
 by the name common Salt. The Salt fprings of different countries are impreg- 
 nated with different proportions of Salt, and the Salt itfelf differs alfo in degree 
 of ftrength. The brine at Halle is one of the richeft in Germany ; a pound of 
 this contains three ounces and three drams of Salt, while feveral others hold 
 fcarcelya quarter of an ounce upon a pound (0). On the other hand theLu- 
 neburg and Hartzeburg Salt, and fome others, are ftronger and better, and 
 fhoot into larger cryftals than that of Halle. An account of the falt-works at 
 Halle may be feen in Hoffman’s obfervations ; and an account of mod, if not 
 all the places in Europe where Salt is boiled, or foffile Salt dug, in the Breflau 
 collections. 
 
 In 
 
 ( 0 ) Quantity of Salt in faline fprings.] Seve- fixteen ; which is as large a proportion of 
 ral brine-pits in England are richer in Salt Salt as water will diffolve. The Droitwich 
 than thofe above-mentioned. Thofe of brine is faid to be pure from fcratch, and 
 Droitwich contain four ounces on fixteen ; fcarce to hold any bittern, whilft all others 
 and feveral pits at Northwich, and at Bar- contain both, 
 ton in Lancafhire, no lefts than fix upon 
 
Mineral Salts. 213 
 
 In the boiling of the brine, fome oxes blood is commonly added to promote C o m m o n 
 Are reparation of the impurities, which arife with the blood to the furface of the S a l t. 
 liquor, and are thence fcummed off: Some beer is added to promote the gra- 
 nulation or cryflallization of the Salt : Wine anfwers the fame purpofe, and 
 rectified Spirit of Wine dill more effectually. The crydals are firft formed on 
 the furface, but growing gradually larger from the accretion of frefh matter, 
 they fink to the bottom, from whence they are taken up with wooden mftru- 
 ments, and put in bad-rets to drain. 
 
 In fome places where the brine is lo dilute that the quantity of Salt would not Concentrate 
 pay the expence of fuel necelfary for the evaporation, and where neither the on of falme 
 fun’s heat nor froft can be applied to advantage, a method has been contrived of water by air, 
 concentrating the liquor, or diffipating great part of the fuperfluous water, by 
 means of air and wind: Large buildings are ereCted open every way to the air, 
 with citterns and channels, where the brine is conltantly dripping, or fall- 
 ing in (lender dreams, through bundles of draw, horfe hair, faggots, A 
 
 part of the water being thus carried off, the red is evaporated by fire. There 
 are works of this kind at Nauenheim near Francfort, at Saltzungen, Afcher- 
 fieben, Allendorff, Saltza, Hellen, Saltzgutter, near Lutzen in Merfeburg, 
 near Colberg in Pomerania, and in feveral other places. The procefs how- 
 ever is not a little troublefome and incommodious. The ftrength of the brine 
 is judged of by the hydrometer, or by weighing equal meafures of the brine 
 and of common water. Didillation, redifiolution, and crydallization are the 
 fured teds, but require too much time and trouble to be praCtifed at the 
 works. 
 
 Pure common Salt di(folves eafily in lefs than thrice its quantity of water, chemical 
 into a clear colourlefs liquor, which depodtes no fediment : On gentle evapo- properties of 
 ration the Salt concretes into cubical crydals, hollow at top, pointed at common Salt, 
 bottom, hard, compact, colourlefs, and tranfparent : The loft, crumbly 
 kinds, and fuch as grow moift in the air, are inferior in drength to the folid. 
 
 Laid on burning coals, it crackles, burds in pieces and flies about, in- 
 creafes the flame, and is in part diflipated. It eafily melts, and at the fame 
 time lofes a little of its acid, the Alcali being now found to prevail fo much, 
 that the Salt liquefies in the air. It is eafily volatilized by fire, and by putrefac- 
 tion along with fubflances difpofed to that procefs. By repeated folutions and 
 calcinations, it may be totally dedroyed or converted into earth: By thirteen 
 repetitions of thefe operations, a pound of Salt was reduced to half an ounce, 
 the earth amounting to three drams, and the Salt that remained unchanged 
 only to one. 
 
 The three forts of common Salt appear when perfectly pure, to be one and Differences of 
 the famt, but in their common date fome little differences may be obferved lea, brine, a nd 
 in them. The fea and Spring-falts never (hoot into fuch large and folid cry- Saits ’ 
 dais as the Sal gem : The crydals of the Spring-falt are the fmallefl of the 
 three, and likewife the weakefl. Sea-falt frequently contains a little nitrous 
 matter, produced from the putrefaction of vegetable or animal fubflances in 
 the fea •, hence the acid fpirit extracted from it is fometimes obferved to diffolve 
 Gold, which the marine acid is incapable of doing without the afliftance of the 
 nitrous. Alcaline Salts added to a folution of the fea or Spring-falts, render 
 
 the 
 
214 Mineral Salts. 
 
 Co mm o n the liquor turbid or milky, and precipitate an earthy matter, amounting to 
 S a lt. about ten grains from an ounce of Sea- fait, and twelve grains from the lame 
 v — — v— — quantity of Spring- fait ; added to a folution of Sal gem, they occafion no pre- 
 cipitation or turbidnefs. 
 
 Spirit of Salt, The acid of common Salt is extracted in the fame manner as that ofNitre, 
 ^hodsof d'Tl* e ' c ^ er ky the addition of a more powerful acid, which may dillodge it from its. 
 lii!^ 0 ilJ '^ xe d alcaline bafis, or of vitrelcible earths, as fand, with which in a ftrongfire, 
 the Alcali melts into Glafs, letting go its acid. The firfl: of thefe methods is 
 the only one praCtifed, the latter being extremely troublefome and incommo- 
 dious. Both the vitriolic and the nitrous acids expel the acid of common Salt t 
 The firft is preferred, as being the mod powerful, and as a part of the nitrous 
 acid would arife along with the marine, and thus inftead of a pure fpirit of Salt, 
 produce an Aqua regia. 
 
 The old method of diftilling fpirit of Salt was with red Bole, ruddle, or other 
 coloured bolar earths : Thefe were moiftened with a ftrong folution of the Salt 
 into the confiftence of a pafte, then formed into little balls, the balls dried and 
 diftilled in earthen retorts : The fpirit thus obtained was in fmall quantity, and 
 very phlegmatic. It was endeavoured to be freed from the redundant phlegm 
 by rectification, or rediftilladon in glafs retorts; but the great volatility of the 
 marine acid renders it incapable of being concentrated to any confiderable de- 
 gree by this method, the acid vapours arifing in part along with the water. 
 
 The earths in the foregoing procels, as in the diftillation of Spirit ofNitre, 
 were of no further ufe than as they were impregnated with vitriolic acid ; and 
 hence fubftances participating more largely of that acid were employed to much 
 greater advantage. Calcined Vitriol readily and effectually extricates the acid 
 of the common Salt, but one of the peculiar qualities of the marine acid ren- 
 ders it an improper addition ; this acid, when difunited from its own alcaline 
 bafis, adhering fo flrongly to the metallic part of the Vitriol, as fcarce to be 
 elevated in diftillation. Alum is free from this inconvenience: The common 
 Salt may be mixed with thrice its weight of Alum moderately burnt, and the 
 mixture committed to diftillation in glafs retorts in an open fire : The diftilled 
 fpirit may be drawn over from a little frefh common Salt, which will abforb 
 and keep down any of the aluminous or vitriolic acid that may have arifen in 
 the firft diftillation. But the marine fpirit is moft fpeedily and effectually fepa- 
 rated by oil of Vitriol itfelf ; and the fpirit obtained by this means is the 
 ftrongeft and moft: concentrated : It is fo fubtile and volatile, that its vapours 
 will lcarce condenfe in the recipient, and can lcarce be confined by any luting, 
 its fmell being diffufed throughout the whole elaboratory : Hence it is advifable 
 to place in the recipient fome fpirit of Salt already made, with which the fumes 
 may incorporate. The moft commodious method of performing the procefs, 
 is to put the Salt firft into a tubulated retort, and drop in the oil of Vitriol 
 through the aperture of the tube by a little at a time : If much of the Oil was 
 poured in at once, the fumes would arife fo haftily and copioufly as to endan- 
 ger fuffocating the operator •, and if poured in by the mouth of the retort, it 
 would be apt to foul the neck. In all the diftillations, the fudden ceffation of 
 the white clouds, or the receiver growing clear before the fpirit has come over, 
 are marks that the retort has cracked. 
 
 Spirit 
 
Mineral Sal t s. 
 
 215 
 
 Spirit of Salt has been employed by fome for cleaning and whitening theCoMMOM 
 teeth. A French pried, father deCabriere, gave it in ruptures, and vended it Salt. 
 as an extraordinary panacea, to the prejudice of the health of many, efpecially < - 
 of thofe who had weak lungs. An empyric, Mcebius, vended a liquor by the^^of Spirit 
 name of ‘Tinblura aperitiva , which, as Hoffman and Barchuyfen [affure us, was 01 
 no other thanfpirit of Salt, tinged with turnfol orrofes, and abated a little of 
 its acidity by a fmall admixture of Salt of Tartar : The quantity of the alca- 
 line Salt is laid to be only half a dram, or at moll a dram, to a pound of the 
 fpirit of Salt ; a notable arcanum truly ! Spirit of Salt in its corrofive ftate, is 
 by no means fit for internal ufe. 
 
 This acid is dulcified like the other mineral acids, by Spirit of Wine. One part Dulcified SpL 
 of Spirit of Salt is commonly mixed with three parts of highly redlified Spirit rit of Salt, 
 of Wine, the mixture digefted and diftilled : .But as ordinary Spirit of Salt is 
 very phlegmatic, and as phlegmatic acids are unfit for dulcification, wefeldom 
 meet with a good dulcified Spirit of Salt in the (hops. The bell method of ob- 
 taining fuch a fpirit is, to place the Spirit of Wine in the receiver, in the diftil- 
 lation of the fmoking Spirit of Salt with Oil of Vitriol : By this means we ob- 
 tain a mixture of the concentrated marine acid with the inflammable fpirit, 
 which are afterwards to be more perfe&ly combined together by digeftion and 
 diftillation. Three or four ounces of the vinous fpirit may be taken to every 
 ounce of common Salt. 
 
 Spirit of Salt faturated with Salt of Tartar, yields on cry ftallization a neutral Regenerated 
 Salt called regenerated Sea-falt. This is of a fharper tafte than common Salt Sea-falt. 
 itfelf, and differs from it in fome other refpefls, the alcaline bafis of common 
 Salt being different from the alcaline Salt of Tartar, or any of the vegetable 
 alcalies. When the nitrous acid is poured upon common Salt, the marine acid 
 will be extricated, and readily diflipated by heat, the nitrous remaining com- 
 bined with the Alcali of the common Salt, with which it fhoots into cubical 
 eryftals, whereas with the common vegetable alcalies it forms long hexangular 
 prifms. Oil of Vitriol combined in like manner with the marine Alcali, forms 
 a neutral Salt which eafily diffolves in water, and eafily melts in the fire, called 
 by its inventor Glauber, Sal mirabile ; whilft a Salt compofed of the fame acid 
 and vegetable alcalies is extremely difficult of folution, and does not melt at all. 
 
 It muff; be obferved however, that when the common alcalies have been fatu- 
 rated with Spirit of Salt, and this compound treated with oil of Vitriol ; the 
 neutral Salt hence refulting, after the expulfionof the marine acid, will greatly 
 relemble the Sal mirabile. 
 
 The marine acid is feparated and transferred into other bodies, in fundry Tranfpofitk 
 operations, where fuch an effedt is generally little thought of. Thus in the ons of the 
 making of corrofive Sublimate, it is the acid of the Sea-falt that unites with acid * 
 the Mercury : And in the making of butter of Antimony, it is this acid which 
 forfaking the Mercury corrodes the antimonial Regulus into a butyraceous 
 form. 
 
 II. S A L 
 
ineral Salts. 
 
 216 
 
 Sal Am- 
 moniac. 
 
 II. SAL AMMONIAC. 
 
 Whether 
 
 tive. 
 
 na- 
 
 Prepared in 
 
 Egypt. 
 
 Its name. g A L AMMONIAC is a neutral Salt compofed of the marine acid and 
 volatile Alcali: Combinations of other acids with volatile Alcalies are called 
 # alfo from the name of this Salt ammoniacal. The name Ammoniac is derived 
 
 by Salmafius from one of the Cyrenaic territories, Ammonia ; by others, from 
 the temple of Jupiter Ammon in Africa; by others from the Greek olp 
 fand, or k^ovuuxov fandy, the Salt being faid to have been found plentifully 
 in Ammonia, and near Ammon’s temple,- in fandy grounds. 
 
 The Sal ammoniac of the ancients is commonly fuppofed to have been a 
 fpecies of Sal gem. The true modern Sal ammoniac is never found native, at 
 lead not in any tolerably pure date. The faline matters thrown out by Volca- 
 nos, and which are commonly faid to be Sal ammoniac, have often little or 
 nothing of an ammoniacal nature. They are of various colours, red, green, 
 yellow, and others: In fome forts I have found a little volatile Alcali, but the 
 greater number contained none : Some participated of the vitriolic acid, and 
 fome of the marine; fome held an actual Sulphur, and fome had a cupreous or 
 ferrugineous impregnation. 
 
 Common Sal ammoniac is an artificial preparation, hitherto made only in 
 Egypt. The principal manufafture is at two villages lying near together, 
 about a mile from the city Menfoura in the province of Delta, called Damire 
 or Dameyer. In thefe there are twenty-five large and feveral fmaller works ; 
 and fifteen hundred or two thoufand quintals or hundred-weights of Sal ammo- 
 niac are prepared every year. There are three other works in Egypt, lefs 
 confiderable than the foregoing, two in the fame province, and one at Cairo ; 
 in which laft, the annual produce of Salt does not exceed twenty or thirty 
 hundred weight. It is furprizing that means have not been found of preparing 
 this commodity to advantage in Europe, as its conftituent parts are perfe&iy 
 known. 
 
 Enquiry into The ingredients from which Sal ammoniac is produced have long been men- 
 preparati- t i 0nec j j n books. Caefalpinus, if I miltake not, was the firft who informed 
 us, that this Salt is obtained from foot, urine and common Salt; and from 
 thefe, it is ftill affirmed that the Egyptian Sal ammoniac is made: The pro- 
 portions commonly fet down are, ten parts of urine, two of common Salt, 
 and one of wood foot. There is however, in regard to thefe ingredients, a grand 
 mifunderflanding, which fo far as I can learn, was firft difcovered by Paul 
 Lucas (who travelled through Egypt and other parts of Africa) and afterwards 
 confirmed in the year 1719, by the French conful at Cairo, by father Sicard, 
 and more lately by one Granger. The Egyptian foot is not the fame with 
 ours : It is the foot of animal dung, chiefly of that of cows ; which is the com- 
 mon fuel of that country, either dried by itfelf or mixed with ftravv. The 
 urine employed in the making of Sal ammoniac, is that of horfes, afles, or 
 camels ; and as the foot abounds much more than ours with a volatile animal 
 Salt, the urine alfo is richer in faline matter than that of the fame animals in 
 thefe colder climates. 
 
 its 
 
 on. 
 
 Of 
 
Mineral Salts. 217 
 
 Of the manner in which Sal ammoniac is made from the foregoing ingre-S a l A m- 
 dients, we have not as yet fo full an account as could be wifhed. Two of the moniac. 
 French chemifts, the younger Geoffroy and the younger Fernery, difputed 
 for feveral years whether it was prepared by fublimation or infpiffation : Geof- 
 
 froy maintained the former, and Lemery the latter. Geoffroy gave one me- 
 moir on the fubjed; in 1705, and another confirming his opinion in 1716; but 
 the academy, either imagining that Lemery was in the right, or that both 
 opinions were equally well founded, fuppreffed Geoffroy’s memoir, till an ac- 
 count lent by the conful at Cairo convinced them that the Salt was made by 
 fublimation. This gentleman obferves, that the fubliming veffels are made of 
 earth or glafs, of a globular figure, generally a foot and a half in diameter, 
 with a neck about two fingers high, like the common receivers j that forty or 
 fifty pounds of the matter are put into one veffel ; that in every large ela- 
 boratory there are eight furnaces, and in every furnace fixteen fubliming vef- 
 fels •, that the veffel is left open for a time, till the phlegmatic parts have ex- 
 haled, and afterwards covered ; and that the procefs takes up three days and 
 nights. This is all we know as yet of the manufacture of Sal ammoniac : 
 
 Granger has made fome additional obfervations, but they contribute nothing 
 to the principal point. 
 
 With regard to the ingredients, I am fully perfuaded, that urine, foot, and 
 common Salt are not all. The common Sait would not part with its acid, and 
 confequently could be of no manner of ufe without the addition of Loam, 
 
 Bole, or fome of the other fubftances employed for the diftillation of Spirit of 
 Salt ; and fome fuch addition is doubtlefs employed by the Egyptians, though 
 it has efcaped the notice of the gentlemen above-mentioned If the prepara- 
 
 tion of Sal ammoniac is attempted in this country, we are not to be confined 
 to urine and the foot of dung. This Salt confifts of marine acid and volatile 
 Alcali : The acid may be obtained by proper intermedia from all the forts of 
 common Salt, and all animal matters furniih a volatile Alcali. Different ani- 
 mal fubftances yield different quantities of Alcali •, and fuch are to be made 
 choice of for this ufe as yield the mod, and are to be procured at the leaft ex- 
 pence, as dung, urine, refufe cuttings of leather, horn, bone, hoofs, hair, 
 wool, CdV. 
 
 With regard to the procefs, I apprehend that both Geoffroy and Lemery 
 are partly in the right, but neither of them entirely fo. The production of 
 the volatile Alcali, and its combination with the marine acid, are doubtlefs 
 effected by fublimation: But the form of the cakes in which Sal ammoniac is 
 brought to us, appears to be procured by infpiffation. If we fublime Sal am- 
 moniac in the fame kind of veffels in which it is faid to be fublimed at firft, it 
 will by no means concrete into cakes, nor does any Salt we know ofaffume 
 fuch a form by that procefs : On the other hand, by foftening the powdered 
 
 Salt with water into the confidence of pap, and pouring it into fuch a glafs as 
 isufed for deliquiations, (having a fmall aperture in the bottom forfuffering the 
 liquid part to drain off) I have obtained a cake exaCtly refembling the Egyp- 
 tian. The hemifpherical fide of the cake, and the prominence in the middle, 
 which Geoffroy fuppofes to correfpond to the upper part of the fubliming vef- 
 fel, were here formed by the bottom of the infpiffating veffel. In the middle 
 
 F f of 
 
'i 1 8 
 
 Sal A m- 
 
 MON’IAC, 
 
 Cakes and 
 loaves. 
 
 General pro- 
 perties. 
 
 Sublimation. 
 
 Deflagrates 
 with Nitre. 
 
 Volatilizes 
 
 metals. 
 
 Made fixed. 
 
 Mineral Salts. 
 
 of the cakes of Sal ammoniac we find lbtne manifeft cryftals ; and the reft of 
 the mafs is throughout of luch an uniform and continued ftrudture, as could 
 not have been produced by conftant cafual appofitions of frefla matter. The 
 infpiftation appears to be performed by the Egyptians in glafs velfeis, as we 
 frequently find pieces of glafs adhering to the cakes. 
 
 Two kinds of Sal ammoniac are diftinguifhed in trade, one in broad cakes, 
 convex on one fide and flat on the other, about two inches and a half or three 
 inches thick ; the other in large conical loaves, refembling fugar loaves and 
 probably formed in the fame kind of moulds. This laft fort is faid by fome 
 to be the produce of the Eaft-Indies: It is very rarely met with among us ; 
 the fir ft fort, which is the moft pure, being the only one in common ufe. 
 The cakes are ufually blackifh on the outfide, but internally white, femi- 
 tranfparent, efpecially about the edges, hard, compadt, and in fome degree 
 fonorous, of a fharp tafte without any fmefl. 
 
 Sal ammoniac difTolves in four times its weight of water, and renders the 
 liquor fenfibly colder : The greateft degree of cold hitherto produced in water 
 by artificial mixture, without ice, refults from a compofttion of Sal ammo- 
 niac, Mercury-fublimate, and Vinegar. Several experiments of this kind, 
 and of vegetations or curioufly figured cryftallizations of Sal ammoniac may 
 be feen in the French Memoirs. It is faid, that a folution of Sal ammoniac 
 wrote with on paper, on which it leaves no ftain, will become viflble on ex- 
 pofing the paper to the fire ; and that paper or linen moiftened with this folu- 
 tion will not burn. On trial the writing did not become legible when heat- 
 ed (/>), and the paper impregnated with the Salt, burnt and confumed, though 
 it did not flame. 
 
 Sal ammoniac proves totally volatile in a heat confiderably below ignition, 
 nearly in fuch a degree of heat as Lead requires for its fufion. If no other 
 fubftance is added that may difunite its conftituent parts, it fublimes un- 
 changed. By repeated fublimations however, it acquires at length a yellowilh 
 tinge, and a particular fmell, of which it difcovered nothing at firft. Thefe 
 alterations proceed from the oily or inflammable matter of the volatile animal 
 Salt-, for that Sal ammoniac participates of that principle, appears from its de- 
 flagration with Nitre. The detonation is moft obfervable when four parts of 
 Nitre are mixed with one of the Sal ammoniac; a mixture of three parts with 
 one deflagrate but weakly, and two with one, not at all. 
 
 This Salt remarkably opens and volatilizes metallic bodies, efpecially if they 
 have been previoufly reduced into calces or precipitates ; even the moft fixed 
 of all known fubftances. Gold, may be forced over the helm by means of Sal 
 ammoniac : Regulus of Antimony is fo attenuated by it, as to diflolve in 
 Vinegar, if not in water. By repeated fublimations, both the Salt itlelf, and 
 combinations of it with other bodies, become lefs and lefs volatile. Pure Sal 
 ammoniac after a number of fublimations, proves at length fo fixed as to re- 
 main half fluid in the bottom of the fubliming veflel. On fubliming Mer- 
 cury- 
 
 (p) Characters drazvn with folution of Sal fcorch the paper, the part impregnated with 
 ammoniac not legible when heated.] They do the faline folution will be burnt blacky 
 not become vifible by being moderately whilft the reft is fcarcely brown, 
 treated ; but if the heat is fuch as to fiightly 
 
Mineral Salts. 219 
 
 cury-fublimate with Sal ammoniac, mixing the matter which arofe with theS al Am- 
 refiduum, and repeating the operation feveral times, the matter at lall became moniac. 
 
 quite fixed in the fire, and would no longer rife from the bottom of the glafs, ' — 
 
 On fubliming together a mixture of Sal ammoniac, Mercury, and Sulphur, 
 there remains every time a little fixed brownifh-red matter, which bears a 
 confiderable melting heat, and is called by fome fixed Cinnabar. 
 
 Sal ammoniac is made ufe of in fundry mechanic bu fine fifes, by the dyers, ufes - 
 glafs-makers, but more particularly by thofe who work upon metals, for fol- 
 dering, i£c. Gold is taken off from gilt Silver, by heating the vefiel red-hot, 
 and quenching it in a folution of a pound of Borax, a pound of Tartar, and an 
 ounce and two drams of Sal ammoniac— —As a medicine, it is accounted 
 powerfully antifeptic, aperient, diuretic and diaphoretic. A dofe of half a 
 dram, or a dram, is recommended in quartan agues; and faid, if it fails the 
 firft time, to cure with certainty on repeating it: Experience has fhown, that 
 it is a medicine of remarkable efficacy in agues, though it does not in all cafes 
 fucceed. Given too frequently, or in too large dofes, it is faid to injure the 
 ftomach and chill the habit. Externally it is employed againft films on the 
 eyes of cattle, in gargarifms for quinfeys, in applications for gangrenes, forre- 
 folving fwellingsand nodes in the breafts, when not of long (landing or accom- 
 panied with inflammation, and for other like purpofes. An ointment againfl 
 nodes and foft excrefcences is compofed of fix ounces of Sal ammoniac, three 
 drams of Cerufie, one dram of Camphor, and a proper quantity of Oil of 
 Rofes. 
 
 The mod Ample preparation of Sal ammoniac is its purification. This is Purification, 
 effected either by folution in water, filtration and cryftallization, or by fubli- 
 mation. The firft method is greatly to be preferred ; for fublimation fepa- 
 rates only the fand, bits of glafs, or other like grofs fubftances that have been 
 cafually mingled with the Salt, the footy and oily impurities fubliming along 
 with it. By fublimation alfo the inflammable principle of the Sal ammoniac 
 more and more difcovers itfelf, and communicates both a colour and fmell to 
 the Salt. By folution and cryftallization it is effectually purified from all the 
 fubftances commonly mixed with it, that are not efiential to its compofition. 
 
 Some fublime the Sal ammoniac from common Salt : This addition fomewhat 
 varies its quality, efpecially if the fublimation is feveral times repeated, a por- 
 tion of the volatile acid of the common Salt being imbibed by the Sal am- 
 moniac. 
 
 The martial flowers of Sal ammoniac are prepared commonly from one part p^Iartial 
 of Iron filings or Lapis hamatites and two of the Salt, mixed well together, let flowers, 
 by for fome days in a cellar, ftirred two or three times a day, then put into a 
 low glafs body fitted with a head, and expofed to a gentle heat till the matter 
 becomes thoroughly dry; after which, the fire is increafed till nothing more 
 will fublime. After the water has arifen, a volatile fpirit comes over, and after 
 this a little acid fpirit. The flowers which fucceed, are of an orange yellow, a 
 reddifh and pale yellow colour, and are found to be no other than the Sal am- 
 moniac in its whole lubftance, tinged by the Iron which it has volatilized. The 
 reliduum deliquiates in the air, and appears to be no other than a folution of 
 the Iron in marine acid. Iris euftomary to grind the flowers with the refi- 
 
 F f 2 duum, 
 
220 
 
 I N E R A L 
 
 S A L T S. 
 
 Delique- 
 
 Sal AM-duurn, and fubliine them afrefh to repeat this operation feveral times, the 
 m oni ac, flowers becoming by this means of a deeper and deeper red colour. I once 
 tried how much Sal ammoniac a certain quantity of Hematites was capable of 
 tinging : Atfirfd I took two pounds of each, and to the refiduum of this pro- 
 cefs added one pound of frefli Sal ammoniac, repeating the lublimation with 
 a pound of Sal ammoniac every time for twelve times fucceffively. All the 
 fourteen pounds of Sal ammoniac were thus tinged by the two pounds of blood- 
 idone : Till the eleventh fublimation the flowers feemed to be deeper and deeper 
 coloured, but thole of the following fublimations were paler : On mixing 
 with the laid refiduum another pound of Sal ammoniac, the fublimate had little 
 colour; and on trying a pound more it arofe grey. Some infdead of filings of 
 Iron or Bloodfdone, uled Crocus of Iron, or Caput mortuum of Vitriol: The 
 flowers in either cafe are the fame. 
 
 It is obfervable, that green Vitriol and Sal ammoniac ground together grow 
 Renee of Sal fo ft as pap, and in part liquefy, efpecially if the quantity of Vitriol is double 
 ainmomatandor equal to that of the Sal ammoniac. There feemsto happen here a tranfpo- 
 fition of the conftituent parts of. the ingredients: The acid of the Vitriol is 
 transferred into the volatile Alcali of the Sal ammoniac ; and the acid of the 
 Sal ammoniac into the Iron of the Vitriol : Hence the tafde of the compound 
 is extremely ftyptic, like that of the common folutions of Iron in the marine 
 acid. 
 
 Venereal and antimonial flowers of Sal ammoniac have likewife been pre- 
 pared for medicinal ufe, the firfd by fubliming the Salt with Caput mortuum of 
 blue Vitriol, the latter with Regulus of Antimony. The antimonial flowers 
 are one of the more violent preparations of that mineral ; and the venereal 
 ones, like the other preparations of Copper, are entirely unfafe. The Ample 
 Regulus of Antimony yields white flowers ; the martial Regulus fine red ones, 
 efpecially if the fublimation be feveral times repeated till little or nothing is 
 left. 
 
 Sal ammoniac diffolved in four times its quantity of Spirit of Nitre, makes 
 the common Aqua regis : The Salt fhould be previoufly pulverifed in a glafs 
 or {done mortar; and a gentle warmth applied to promote its folution in the 
 fpirit. If a fpherical glafs veflel be nearly filled with good Spirit of Nitre, a 
 quantity of Sal ammoniac, more than it can diffolve, thrown in, and the whole 
 luffered to remain quiet, a curious vegetation arifes, which Kunckei was the Arid 
 1 know of that obferved. Sal ammoniac, Quick-lime and water, kept for a 
 night in a Copper or brafs veflel, or along with pieces of Copper, diflblve a 
 part of the metal, by which the liquor is tinged blue : This is the Aqua c^erulea 
 or Sapphirina of the fhops. The Copper is here diffolved by the volatile Altali 
 of the Sal ammoniac extricated by the Quick-lime. 
 
 The volatile alcaline Salt, and the fpirit, or folution of the volatile Salt, are 
 general pnu- principal preparations of Sal ammoniac kept in the fhops. The volatile 
 C 'aratiOi ^ 6 -^lcali is never to be feparated without the intervention of fome other body with 
 which the acid has a greater affinity, as fixed alcaline Salts or abforbent earths. 
 One part of powdered Sal ammoniac is commonly mixed with two or three of 
 Sait of Tartar or purified Potafh, the mixture moifdened with a little Spirit of 
 Wine, put into a retort, to which a receiver is adapted, and the fire increafed 
 
 Flowers of 
 Copper; of 
 Regulus of 
 Antimony. 
 
 Aqua regia. 
 
 Volatile Saft; 
 
221 
 
 Mineral Salts. 
 
 by degrees : In England whiting is ufed for the intermedium, and aludels areS al A m- 
 iometimes applied to the retort. By either of thefe methods, the volatile SaltMON i ac, 
 fublimes in a concrete form, the marine acid of the Sal ammoniac remaining v_ — -v — '-J 
 united with the fixt Salt, or the whiting, at the bottom of the retort. 
 
 Tournefort obtained ten ounces of volatile alcaline Salt from fifteen of Sal quantity, 
 ammoniac. Hoffman affirms that fixteen ounces of Sal ammoniac contain 
 twelve of Alcali and four of Acid. Geoffroy obtained no lefs than thirteen 
 ounces from fixteen, befides a confiderable quantity of fpirit, that is of Salt 
 difiolved ; infomuch that he concludes fifteen ounces in the pound to be pure 
 volatile alcaline Salt, and only one ounce acid. (See the French Memoirs for 
 theyear 1723.) He appeals to two other experiments for the truth of this 
 affertion. The firft is, the production of a Sal ammoniac perfectly neutra- 
 lized, from fifteen ounces of volatile alcaline Salt and a quantity of Spirit of 
 Salt that fhall be found to contain an ounce of pure acid : The fecond experi- 
 ment is, that if a mixture of three parts of dry Salt of Tartar and one part of 
 dry Sal ammoniac be ftrongly calcined in a crucible, that all the volatile Alcali 
 may be expelled, the acid retained by the Salt of Tartar will increafe its weight 
 only one fixteenth of the weight of the Sal ammoniac employed. It feemed to 
 me improbable, that a fingle ounce of acid fhould fully iaturate fifteen ounces 
 of volatile Alcali ; and therefore I repeated both the fublimation and the coun- Salt of Tartar 
 ter-proofs he appeals to. One pound of Sal ammoniac, and three of Salt of volati h zcd - 
 Tartar, thoroughly dried, and reduced into fine powder, were well mixed to- 
 gether, put into a retort, the jun&ures clofely luted, and after Handing for a 
 night fublimed : The volatile concrete Salt amounted to no lefs than thirteen 
 ounces : There was alio fome fpirit, but not fo much as that two ounces more 
 of Salt could be reckoned for it; and the quantity of refiduum was a good deal 
 greater than Geoffroy’s. I repeated the experiment with pure dry Salt of Tartar 
 prepared on purpole, and with purified Potafh : With this laft the quantity 
 
 of volatile Salt was an ounce lefs than with the other. With regard to the 
 other experiments, an ounce of pure and pretty ftrong Spirit of Salt required 
 for its faturation two drams of volatile Alcali ; and fixt Alcalies calcined with 
 Sal ammoniac, inftead of gaining loft notably of their weight. Three drams 
 of Salt of Tartar, alter gentle calcination with one dram of Sal ammoniac, 
 weighed but two drams thirty-four grains : The fame quantities calcined by a 
 ftronger fire, left but one dram and two fcruples. I likewile calcined fome 
 Salt of Tartar by itfelf, and found it to lofe ten grains upon a dram : Calcined 
 with twice its weight of Sal ammoniac it loft exa&ly the lame. Half a dram of 
 the calcined Salt being mixed with half a icruple of Sal ammoniac, there re- 
 mained after calcination no more than twenty-five grains. From thefe experi- 
 ments it appears, that a part of the Salt of Tartar is volatilized by the Sal am- 
 moniac (j), and that the Sal ammoniac does not contain fo much volatile Sait 
 
 as 
 
 ( q ) Salt of Tartar volatilized by Sal ammo- rnoniac : By both intermedia he obtained 
 niac.'] Mr. du Hamel has fully proved that a more, fometimes one half more volatile 
 confiderable portion both of fixed alcaline Salt, than the quantity of crude Sal ammo- 
 Sal ts and of Chalk, is elevated in fubiima- niac made ufe of : Even the volatile Salt it- 
 tion along with the volatile Salt of Sal am- fell, by bare fublimation from fixed A lea- 
 
222 
 
 Mineral Salts. 
 
 Sal Am- as is produced in its analyfis. Probably Geoffroy’s obtaining more volatile 
 m,on i a c. Salt proceeded from fome differences in the fixed Salts made ule of : TheFrench 
 Potalh, and Quick-lime, are found in fome experiments to differ from ours : 
 Proceffes with Quick-lime, which I have performed numbers of times at Lon- 
 don without once failing, I could never once make fucceed at Paris. 
 
 Spirit of Sal Spirit of Sal ammoniac is no other than the volatile Salt diffolved in phlegm 
 ammoniac. 0 r water. The mod commodious method of preparing it is, to diffolve the 
 Sal ammoniac in as little water as it will diffolve in, and to pour into this folu- 
 tion, in a retort, a folution of an equal quantity or more of Salt of Tartar or 
 Potafh, then immediately to lute on a receiver, and proceed to diftillation with 
 a gentle fire : The volatile Salt will arife before the water, and concrete about 
 the Tides of the receiver : When water enough has come over to diffolve the 
 Salt, the procels fhould be difcontinued. The fpirit will now be fully faturated 
 with Salt; whereas if the diftillation is protradted beyond this period, the fpirit 
 will be proportionably weakened or diluted. 
 
 Calcareous earths, as Chalk or Whiting, extricate the volatile Alcali of Sal 
 ammoniac as effedtually as fixt Alcalies ; but they do not produce their effedt 
 till they have buffered fome degree of calcination. If Sal ammoniac and fixt 
 Alcali be barely mixed together either in a folid ora liquid form, aftrong pun- 
 gent odour will inftantly dilcover that the volatile Alcali is fetat liberty, but 
 on mixing the Sal ammoniac with Chalk no fmell is perceived till the matter 
 has been considerably heated, and then the volatile Salt fublimes in its proper 
 form. 
 
 Spirit with When the earth is previoufly calcined into Quick-lime, the phenomena are 
 Quick lime. ver y different. Quick-lime mixed with Sal ammoniac, raifes immediately a 
 more volatile and penetrating fmell than that occafioned by fixed Alcalies : 
 From this mixture no concrete Salt is obtainable, the whole of the Salt being 
 converted into a permanently fluid fpirit, and its fubtility and volatility re- 
 markably increaled- The Spirit of Sal ammoniac with Quick-lime may be 
 
 prepared from one part of the Salt, and three of the Lime broke in pieces about 
 the fizeof hazel nuts. The Sal ammoniac is to be diffolved in water, and put 
 into a retort, the Quick-lime thrown in, and a receiver immediately luted on : 
 A fmall quantity of a very fubtile fpirit will arife during the flaking of the 
 Lime: When the heat proceeding from this caufe ceafes, a gentle fire is to be 
 applied, and continued till nothing more will come over. If a ftronger fpirit 
 is wanted, flaked Lime*, and if a ftill ftronger, frefh Quick-lime may be ufed, 
 without any water. From eight ounces of Sal ammoniac and fixteen of Lime 
 flaked in the air, I have obtained fix ounces and fix drams, fometimes more 
 though oftenerlefs: From the fame quantities of Sal ammoniac and frefh 
 Quick-lime I gained only one ounce and fix drams ; but this laft fpirit was far 
 
 more 
 
 lies, in a moderate heat, gained an aug- when neutralized by acids into ammoniacal 
 mentation of its weight. The volatile Salts: A folution of them in water, expofed 
 Salts, thus loaded with Salt of Tartar or for fix weeks to the air, and then exhaled. 
 Chalk, did not part with their fixed matter left nothing behind. But on expofing one 
 on being diffolved in water, and repeatedly of them dry to the air, there remained a 
 fublimed or diftilled with very gentle de- fixed lubftance, which proved to be Chalk, 
 grees of heat : They totally fublimed alio 
 
Mineral S a.l t s. 223 
 
 more volatile than the other, and fo ftrong as to ftrike one down upon Incau- Sal Am* 
 tioufly taking off the receiver : The fpirit with flaked Lime, though far ftronger moniac. 
 than the common Spirit of Sal ammoniac, was mild in companion to this. v— — ■ J 
 
 The Spirit of Sal ammoniac made with fixed alcaline Salts, effervefces Effervefcence 
 ftrongly with all acids ; the lpirit made with Quick-lime very weakly. Hoff- of the vola- 
 man affirms, that the fpirit prepared with Quick-lime raifes no effervefcence 
 with any acid, milled by confounding the aqueous or pure lpirit with the vi- u ,lC1 
 nous. Both the aqueous and vinous lpirits made with fixed alcaline Salts effer- 
 vefee ftrongly : The vinous with Quick lime, not at all; the aqueous with 
 Quick-lime very fenfibly, though not near fo much when newly diftilled as 
 after it has been long kept : On keeping for ten years it loft almoftall its volati- 
 lity and fubtility, andin this date it effervefeed ftrongly — Homberg reports that 
 Spirit of Sal ammoniac raifes no effervefcence with any vegetable acid ; but the 
 fpirit with fixed Alcalies manifeftly does, if added in due proportion, and even 
 that with Quick-lime produces a fparkling. The common vegetable acids are 
 fo dilute, that when they are added to alcaline liquors, a large quantity of the 
 acid muff be poured in to raife any fenfible commotion: To a dram of good 
 Spirit of Sal ammoniac I have often added a pound, a pound and a half, and 
 even two pounds of weak diftilled Vinegar, before the effervefcence begun. 
 
 On the other hand, if we drop the volatile fpirit into ftrong diftilled Vinegar 
 an effervefcence will foon appear. 
 
 The fingular effects of Quick-lime in the diftillation of Sal ammoniac have Divers expe- 
 been accounted for by many, but on principles groundlefs or abfurd : Their true riments with 
 caufe may, perhaps be, that the Quick-lime abforbs and detains the earthy rnat- QiJ lc k-lime* 
 ter which is the bafis of the volatile Salt, and on which its folid form and its 
 effervefcence with acids depend. I have tried the effedfof Quick-lime in com- 
 pofition with fixed Alcalies, and found that four drams of Sal ammoniac and 
 eight of Salt of Tartar, with one dram of Quick- lime moiftened with a little 
 water, yielded both a concrete Salt and a Spirit; that with two drams of Quick- 
 lime a dry Salt was ftill obtained ; but that upon increafing the Quick-lime to 
 three drams and a half, only a fluid volatile fpirit arofe. I have likewife 
 treated with Quick-lime the Salt and Spirit prepared by fixed Alcalies : A 
 little Quick-lime added to the Spirit, diminifhes its volatility more and more 
 in proportion to the quantity of Lime: Twelve ounces of a faturated Spirit be- 
 ing drawn over twenty times from frefh parcels of Quick-lime, three ounces 
 each time, the volatility of the fpirit was in good meafure deftroyed, and by a 
 few more repetitions it was totally fo : The concrete volatile Salt 1 have totally 
 deftroyed by bare Lime-water. [See page 1 6. ] 
 
 The volatile Alcali of Sal ammoniac is extricated alfo in a fluid ftate by c aH ,j ]C v&ja 
 fome metallic fubftances. One part of Sal ammoniac ground with three of tile Spirit, by 
 Minium, and diftilled in a retort, yields afmall quantity of alcaline Spirit, the metallic iub- 
 molt penetrating and cauftic of any volatile Alcalies I know of : A Angle drop ftances ’ 
 laid on the tongue, quickly makes a hole as large as half a pea. The refiduum 
 of this proceis has oftentimes an elegant Marble-like appearance. Some dis- 
 putes with the elder Geoffroy, who in defence of his table of affinity, attributed 
 the extricating of the Alcali of the Sal ammoniac to a fixed alcaline or calcare- 
 ous matter produced in the Minium during its preparation, induced me to exa- 
 5 mine 
 
224 - Mineral Salts. 
 
 Sal Am- mine fome other metallic bodies in their metallic date, where no fuch caufe can 
 mon i a c. be fuppofed to exift : Filings of Lead, Zinc, Regulus of Antimony, Iron, 
 were all found to extricate a little volatile fpirit. 
 
 Volatile with Spirit of Sal ammoniac made with fixed Alcalies, forms on the admixture of 
 vinous faints. rectified Spirit of Wine, a white coagulum, called Offa alba , the volatile Salt 
 not being foluble in the vinous fpirit, and being diflodged by it from the 
 water which held it in lolution before. The fpirit made with Quick-lime, on 
 the other hand, whofe faline matter is fo attenuated as not to affume a folid 
 form, unites equably with the mod highly refti fed Spirit of Wine, without coa- 
 gulation or precipitation. Hence this lad fpirit is much better adapted than 
 
 the other for mixtures with vinous fpirits The vinous or dulcified Spirit of 
 
 Sal ammoniac of the fhops is prepared with fixed alcaline Salts, and confe- 
 quently holds but little of the volatile Alcali : Some mix the aqueous alcaline 
 Spirit with Spirit of Wine, and others ufe a vinous fpirit indead of water, in 
 the fird didillation. 
 
 It may feem a paradox, that volatile Alcalies fhould precipitate a fixed Al- 
 cali, and that they fhould precipitate it from a liquor with which they feem to 
 have themfelves fo little affinity as Spirit of Wine. Such however is the cafe : 
 Stahl’s Mixtura Tonic o-nervina confids of the Tinblura Tartari or TinRura Anti - 
 monii and volatile fpirit ; when a large quantity of the fixed alcaline tindture is 
 added to a fmall one of the volatile fpirit, an Oleum Tartari ■per deliquium fepa- 
 rates to the bottom. 
 
 Volatile cily Sundry compound or oily Spirits of Sal ammoniac are kept in the ffiops for 
 fpmts. inedicinal ufes. There are various compofitions of thefe kinds of liquors, and 
 various methods of preparing them. Different aromatic and other fubdances, 
 asAnifeeds, Fennel-feeds, Lavender, Juniper-berries, Cloves, Saffafras, Am • 
 ber, &c. or the oils diddled from them, fingly or combined with one another, 
 are digeded in the vinous Spirit ofSal ammoniac, or didilled along with it, or 
 added in its fird didillation from Sal ammoniac and fixt alcaline Salt. The 
 didillation of thefe kinds of compofitions is entirely unneceffary, nor is it at all 
 needful to keep them ready prepared in the fhops, as they may be eafily made 
 extemporaneoufiy with different oils, or different proportions of oil, as the 
 phyfician may think fit. It is fufficient if we have at hand a good dulcified 
 Spirit of Sal ammoniac that will readily diffolve oils, 
 ufes of vola~ The Salt and Spirit of Sal ammoniac are the pured of the volatile Alcalies, 
 tile Alcalies. an d hence generally made choice of for chemical operations, as the precipita- 
 tion of A urum fulminans, of Mercury, (Ac. It is obfervable, that thefe fpi- 
 rits precipitate Mercury from Aqua fortis of a blackiffi-grey colour, but from 
 folution of corrofive Sublimate white, and that they give a blackiffi colour to 
 Mercurius dutch. Medicinally, they are exhibited as dimulants, aperients, &c. 
 in paralytic, hyderic, and fundry other diforders : In plethoric habits they 
 fhould be given with caution, as they are apt in thefe cafes to bring on danger- 
 ous haemorrhages. The volatile Salt was formerly given by a dram at a time, 
 but the prefent practice has juftly reduced the dofe within finaller limits. 
 Boerhaave obferves that this Salt is fo corrofive, that when laid upon the 
 moid fkin, and covered with a dicking plader to prevent its flying off, it pa- 
 tently occafions a violent inflammation and gangrene. The Salt either by 
 7 itfelf. 
 
Mineral Salts. 225 
 
 itfelf, or impregnated with odoriferous oils, is ufed in fmelling bottles by the Sa l Am- 
 name ofEnglifh Salts. The fpirit made with Quick-lime is feldom given in- moniac. 
 ternally on account of its great pungency, but frequently ufed for fmelling to, — — v— 
 and in fome external applications : Agitated with oils, it readily unites with 
 them into the confidence of a liniment. 
 
 What remains in the retort after the diftillation of the volatile Salt and Spirit R e fidaa after 
 of Sal ammoniac, is the marine acid of that concrete combined with the inter- the diftillati- 
 medium. When fixed alcaline Salts have been ufed, the refiduum dilfolved in ons - 
 water and cryftallized, proves no other than a regenerated Sea-falt, though 
 dignified with the titles of Sal digeftivum , aperitivum , febrifugum , diureticum , 
 hypochondriacum , embryonatum. Where Quick-lime has been employed, the re- 
 fiduum elixated with water, yields on evaporating the folution, a pungent faline 
 mafs, called Sal ammoniacum fixum, fimilar to one prepared by dilfolving Lime 
 direftly in the marine acid. 
 
 Hitherto we have feen the volatile Alcaii of Sal ammoniac extricated in its Acid fpirit of 
 proper form, by the addition of fubftances which abiorb the acid : We may Sal ammo- 
 likewife obtain the acid in its pure date, by additions which abforb the Alcaii ; niac * 
 for without additions of one or the other kind, no feparation can be made. If 
 Oil of Vitriol be dropt upon Sal ammoniac in a tubulated retort, a highly 
 concentrated marine acid arifes in white clouds, which difficultly condenfe, 
 and in part efcape through the luting, unlefs fome liquid is placed in the 
 receiver to imbibe them and promote their condenfation : This fpirit is in all 
 refpedls the fame with that obtained by the fame means from common Salt : 
 
 The refiduum is the fame with the combination of vitriolic acid and volatile 
 Alcaii called Sal ammoniacum fecretum. See page 194. 
 
 Three parts of Sal ammoniac and two of Nitre, mixed together, and injedfed Aqua pugi- 
 into a tubulated retort made red-hot, yield a compound acid fpirit, participat- lum ‘ 
 ing of the marine acid of the one ingredient, and the nitrous of the other. 
 
 This proves a fubtile kind of Aqua regis : It is called by Bafil Valentine and 
 others. Aqua pugilum , and Aqua chryfulca. In fome places, common Aqua 
 regis is called Aqua chryfulca. This laid name gave once occafion to a fata! 
 miftake: A Polifh gentleman having afked for Brandy by the Polifh name 
 Gorzalko , received the Aqua chryfulca , and was killed by it. 
 
 Article III. 
 
 Combination of the marine acid with earths , 
 
 T he marine acid diffolves all the mineral calcareous earths, and the allies Marine arid 
 of vegetable and animal fubftances, but not all with equal facility or in with different 
 equal quantity. An ounce of Spirit of Salt diffolved but forty-iix grains of eart ^ s> 
 Bezoar-ftone : Of Pearl and Mother-of-pearl it took up two drams, of fea- 
 fhells, Coral, and calcined Hartfhorn fomewhat more ; of Quick-lime, and of 
 flaked Lime, ftill more ; of Crab’s eyes, three drams and upwards : Thefe 
 laft it diffolves not only in largeft quantity, but molt readily of all the earths 
 made trial of. The folutions of fome of the earths, as eggfliells, are in tafte 
 remarkably bitter. 
 
 G g 
 
 All 
 
226 Mineral Salts. 
 
 S a l A m- All the combinations of the marine acid with earthy bodies, when exficcated 
 mon i ac. by heat, liquefy again-in the air ; hence they have been often miftaken for a 
 l ~— ■“ v*" — fixt alcaline Sait, particularly the combination with Quick-lime, which being 
 motiLc^ an *" obtained as a fecondary product in the diftillation of Spirit of Sal ammoniac 
 with that earth, has been in general more known than the others, and diftin- 
 guifhed by the name of Sal ammoniacum fixum . This Salt melts in a fmall heat, 
 like water, and being poured into a clean Iron mortar, appears when cold, of a 
 yellowifh white colour, and femitranfparent like horn. Fixed alcalies added to 
 a diluted folution of it, precipitate the earth, and form with the acid a regene- 
 rated Sea-falt : If the folutions of the fixed Sal ammoniac and of the Alcali are 
 both faturated, inftead of a precipitation, the two liquors coagulate on mix- 
 ture and become confiftent. Homberg obferves, that fixed Sal ammoniac 
 Phofp’norus. me j te( j j nt0 a ma f S;) appears luminous in the dark on being beat in a mortar or 
 ftruck upon with a hammer, and hence calls it a new Phofphorus : The expe- 
 riment does not always fucceed. 
 
 BORAX. 
 
 Borax 
 
 Hiilory. 
 
 I) OR AX is a faline fubftance, of which neither the origin, or the compo- 
 J nent parts are as yet known.' It comes from the Eaft-Indies in little cry- 
 fballine mafies, fomewhat refembling fmall cryftals of Sal gem, mixed with 
 earth and other impurities. Whether it is a natural or artificial production, 
 we have no fatisfadtory account : Molt probably it is in great meafure artifi- 
 cial, and the earthy matter defignedly mixed with it, to make us look upon 
 it as a foffil Salt peculiar to the Indies. It is refined in Europe, but this pro- 
 cefs alfo is kept a fecret : Some additional fubftances are generally fuppofed to 
 be employed, the refined Borax being in larger cryftals than we can make this 
 Salt to fhoot into by itfelf (r). The refining of Borax was formerly pradlifed 
 
 only 
 
 (r) Hifory of Borax.] It is commonly 
 faid, that Borax is prepared in the eaftern 
 countries from a green faline liquor, which 
 runs from certain hills, and is received in 
 pits lined with clay, and fuffered to evapo- 
 rate by the fun’s heat ; that a bluifh mud, 
 which the liquor brings along with it, is 
 frequently ftirred up, and a bituminous 
 matter which floats upon the furface taken 
 off ; that when the whole is reduced to a 
 thick confiftence, fome melted fat is mixed, 
 the matter covered with dry vegetable 
 fubftances, and a thin coat of clay : And 
 that when the Salt has cryftallized, it is 
 feparated from the earth by a fteve. 
 
 In the fame countries is found in confl- 
 derable quantities, a native mineral alcaline 
 Salt on the furface of the earth, foretimes 
 
 tolerably pure, more commonly blended 
 with heterogeneous matters of various co- 
 lours ; the Nitrum or Natron of the ancients, 
 the Bauracb of the Arabians. This Alcali 
 appears to be the fame with the bafts of 
 Sea-falt, and with the lixivial Salt of Kali 
 or Kelp and fome other maritime plants. 
 It differs from the common vegetable Alca- 
 lies, in being milder and lefs acrid in tafte, 
 affirming a cryftalline appearance, not deli— 
 quiating in the air, or very flowly ; form- 
 ing with the marine acid a perfeA Sea-falt, 
 with the nitrous quadrangular Nitre, and 
 with the vitriolic a Sal mirabile. 
 
 Mr. Pott received from Tranquebar, 
 (where the greateft: quantities of Borax are 
 made) a fand, under the name of Ore of Bo- 
 rax, with an account that certain acrid ve- 
 getable 
 
M l N E R A 1; S A L T o. 22 J 
 
 only at Venice, and hence the refined Borax was called Venetian; but the Bo a a x. 
 Dutch are now the only mafters of this manufa&ure. Serapio calls the rough.’"— -v— — ' 
 Borax as it comes from the Indies, 1’incar ; and the dealers in this commodity 
 Hill diftinguifh it by the name Tincar or Tincal, never calling it Borax till it is 
 refined. Bmirach among the Arabians, and Chryfocolla among the Greeks, 
 were names for this Salt, but they were applied alio to other iubftances •, the 
 firft: to the Nartrum or Nitre of the ancients : the latter to a green cupreous mi- 
 neral now called Berggrun or Viride montanum. 
 
 There are great numbers of proceffes in books for making Borax by art : I Brocefies for 
 
 have tried thofe which feemed to be the belt, and made lundry other experi- 
 ments on principles of my own, without being ever able to fucceed. That this 
 Salt is neverthelefs artificially producible, I make no queftion : Stahl obtained 
 
 cryftals 
 
 getable matters were added in the prepara- 
 tion of the Borax. The ore yielded on eli- 
 xation, only the mineral Alcali, with a little 
 Sea-falt. 
 
 The mineral Alcali appears from experi- 
 ment to be a principal ingredient in Borax. 
 On treating Borax with acids, about one 
 fourth its weight of a peculiar faiine fub- 
 flance (called ledative Salt) is feparatcd, and 
 the refid uum proves a combination of the 
 Alcali with the acid employed : Thus when 
 the marine acid is ufed a genuine Sea-falt 
 remains ; when the nitrous, a quadrangu- 
 lar Nitre ; and when the vitriolic, a Sal mi- 
 rabile. The fubftance feparated joined to 
 the mineral Alcali, to the bafis of Sea-falt, or 
 to the Salt of Kali, recompofes Borax again. 
 
 The properties of this fubftance, fo far 
 as they are known, are thefe. It is of a 
 bright fnowy whitenefs, extremely light, 
 compofed of fine plates or fcales, foft, and 
 as it were un&uous to the touch, of no 
 fhnell, of a bitterifh tafte, accompanied with 
 a flight impreflion of coldr.efs. It diflolves 
 difficultly in boiling water, and on the li- 
 quor’s cooling, cryftallizes on its furface, 
 into thin plates ; which uniting and be- 
 coming larger, fall to the bottom. It like- 
 wife diflolves, by the affiftance of heat, in 
 redlified Spirit of Wine : The folution fet 
 on fire burns with a green flame. Moift- 
 ened and expofed to a confiderable heat, it 
 in part fublimes ; by repeated humectations 
 the whole may be elevated. Whilft dry, it 
 proves perfeftly fixed : It melts, emits a- 
 queous vapours, and runs into a vitreous 
 fubftance, difloluble again as at firft : Nei- 
 ther the glafs'nor the Salt itfelf are affe&ed 
 
 by the air. It makes no change in the co- 
 lour of blue flowers. It unites with the 
 common alcaline Salts, in fome degree neu- 
 tralizes, and renders them capable of cry- 
 ftallization. It is faid to expel from Alca- 
 lies every acid except the vitriolic, though 
 expelled itfelf by every acid from the a)ca- 
 line bafis of the Borax. 
 
 Thus we find Borax compofed of two 
 principles, one every where plentiful, ano- 
 ther which has not hitherto been obtained 
 but from Borax itfelf ; the laft in the 
 fmalleft: proportion. How far this peculiar 
 fubftance is natural or artificial, of mineral 
 or of vegetable origin, is wholly unknown. 
 
 With regard to the refining of Borax, the 
 rough Salt is faid by fome to be diflolved in 
 Lime-water, by others in alcaline Lixivia, 
 by others in a Lixivium of cauftic Alcali, 
 and by others in Alum-water. Thus 
 much is certain, that Borax diftolved in 
 common water, and cryftallized in the 
 common manner, forms extremely fmall 
 cryftals: That "thefe differ in feveral re- 
 fpedfs from the refined Borax of the fhops, 
 infomuch that Cramer calls the latter 
 not a purified but adulterated Borax ; that 
 Borax fhoots into larger cryftals when 
 diftolved in Lime-water than in common 
 water ; and when the veflel is covered, and 
 a gentie warmth continued during the cry- 
 ftallization, than in other circumftances . . . 
 It is obfervable that Borax, during its diffb- 
 lution appears tenacious, and adheres in 
 part to the bottom of the veffel : From this 
 glutinous quality, peculiar to Borax among 
 the Salts, it is employed by the dyers for 
 giving a glofs to filks. 
 
 G g 2 
 
228 Mineral Salts. 
 
 Bora x.cryftals approaching to Borax from certain antimonial fcorise expofed for a 
 
 g — J length of time to the air. See his fupplement to Becher’s Pbyfica Subterranea . 
 
 General pro- Refined Borax is a folid, colourlefs, tranfparent, cryftalline Salt, apparently 
 percies. of the neutral kind, but inclining to an alcaline nature. It makes no efferve* 
 fcence with alcalies or acids. It has fomewhat of an alcaline tafle, changes 
 Syrup of Violets greenifh, extricates a little volatile Alcali from Sal ammo- 
 niac, throws down an orange-yellow Precipitate from folution of Sublimate 
 Precipitates corrofive, and precipitates fundry metallic and earthy folutions made in acids, 
 and^akatine as f°l ut i° n °f g reen > blue, and white Vitriol, of Mercury in Aqua fortis, of 
 folutions. Silver in Aqua fortis, of Copper inSpirit of Salt, of Lead in Vinegar, of 
 Copper in Vinegar, of Zinc, of Bifinuth, of Iron in Aqua regis and inSpirit 
 of Nitre, of Alum and of fixed Sal ammoniac. It precipitates alfo fome folu- 
 tions made in Alcalies, as Sulphur diffolved in alcaline Lixivia, and Refin dif- 
 lolved in a folution of fixed Nitre. It precipitates Sulphur from Lime-water: 
 On mixing a folution of Borax with Lime-water itfelf, a turbid nefs and preci- 
 pitation enfue : Spirit of Sal ammoniac made with Quick-lime produces a like 
 eftedl after the mixture has Rood for fome days (s). 
 
 Examined by This Salt requires thirty times its own weight or more of water to difiblve in. 
 water. The cryftals expofed to the fun, lofe a part of the humidity of which they con- 
 tain a large quantity in their cryftalline form, and fall by degrees into a white 
 In the fire, powder. In the fire they readily melt and boil up, and parting with their water, 
 turn to a light, white, fpongy mafs, which on raifing the heat melts into a 
 fubftance like Glafs (/). Lemery relates that this Glafs will ftill diffolve in 
 
 watery 
 
 them feparately: The liquor yields on in- 
 fpiffation, a vifcous tenacious mafs like 
 glue, which refufes to cryftallize, and which 
 deliquiates in the air. Borax affords like- 
 wife a glutinous compound with the other 
 acids, except the vitriolic: It proves moff 
 glutinous with the vegetable, and leaft with 
 
 the marine With oils both expreffed and 
 
 diftilled, it forms a milky femifaponaceous 
 compound. It partially diffolves in Spirit 
 of Wine. In conjunction with any acid, 
 it tinges the flame of burning matters green-: 
 The Precipitate thrown down by it' from 
 metallic folutions has this effect— It does 
 not deflagrate with Nitre. Fufed with in- 
 flammable matters, it yields nothing ful- 
 phureous as thofe Salts do which contain, 
 vitriolic acid. 
 
 (/) Glafs of Borax.'] Borax is the only Salt 
 that affuines a vitreous appearance from fire 
 without addition. The Glafs fo called, 
 becomes opake and at length powdery in 
 the air, like the Borax at .firft, the Salt feem- 
 ing to have fufrered from this procefs no 
 other real alteration than the lofs of about 
 
 half. 
 
 (s) Borax with acids , &c.] All acids dif- 
 folve Borax flowly and without efferve- 
 fcence. It precipitates from them moll, 
 but not all metallic fubftances ; along 
 with which a confiderable part of the Bo- 
 rax is generally depofited. It does not ab- 
 forb the marine acid of Luna cornea or of 
 Mercury-fublimate : It flows upon the fur- 
 face of the firft without uniting, and fuffers 
 the latter to arife unchanged : The Borax 
 in both cafes becomes coloured, in the firft 
 milky with red ftreaks, in the latter ame- 
 thyft or purple. Mixed with Sal ammo- 
 niac, it extricates the volatile Alcali and re- 
 tains the acid ; but. mixed with the combi- 
 nation of the fame acid with calcareous 
 earths, called fixed Sal ammoniac, it extri- 
 cates the acid, and unites with the earth. 
 It extricates the acid of Nitre, without 
 feeming to unite with the alcaline bafis of 
 that Salt. Nor does it mingle in fufion 
 with the common fixed alcaline Salts, the 
 
 Borax flowing diftintft upon the furface 
 
 A mixture of Borax with twice its weight 
 of Tartar, diffolves in one fixth the quantity 
 of water that would be neceftary to difiblve 
 
Mineral Salts, 229 
 
 water, and cryftallize into Borax again. If the fufion is performed in a retort Borax. 
 with its receiver, we obtain from a pound of Borax near feven ounces of -v —— <> 
 
 phlegm ; the vitrified refiduum weighs a little more than nine ounces. The 
 phlegm has fomewhat of a foapy fmell : Jf Salt of Tartar be added in the di- 
 flillation, the diddled liquor proves manifeftly unftuous or oily. Lemery ob- 
 tained from an ounce and a half of Borax and twice as much dry Clay, three 
 drams of an urinous liquor. 
 
 Borax is ufed chiefly in foldering, for promoting the fufion of calces of Gold Ufesa 
 and Silver, and reuniting the particles of thofe metals into one mafs when dif- 
 fufed through a quantity of earthy matter, for facilitating the vitrification of 
 calces of Antimony, &V. It weakens the colour of Gold, and by repeated fu-' 
 fions renders it quite pale (u). It is lometimes employed medicinally in com- 
 pofitions for promoting delivery as an emmenagogue in aphrodifiac, cofmetic, 
 dentifrice, &c. 
 
 The principal preparation of Borax is a volatile faline concrete, called Flores Sedative Salt, 
 ioracis , Sal volatile vitrioli , Flores vitrioli phihfophici , Sal volatile narcoticum , and 
 by fome Sal album alchymijlanm. This is made fometimes with the Caput mor- 
 
 tuum of Vitriol, and fometimes with Oil of Vitriol Three pounds of the 
 
 Caput mortuum or Colcothar of green Vitriol, are elixated with fix or feven quarts 
 of boiling water, and the filtered liquor mixed with a folution of two ounces of 
 Borax in a quart of boiling water. The mixture fuffered to fettle for twelve 
 hours, and poured off clear from the lediment, is evaporated to two pounds or 
 a quart, then put into a glafs body, and treated with a gradual fire : A fine 
 
 fparkling Sublimate arifes, which, after the veflels have grown cold, is to be 
 fwept out with a feather. If the phlegm which comes over be returned on the 
 refiduum, a little more Sublimate may be obtained, and this repeatedly for a 
 fecondand a third time The method of preparing the Salt with Oil of Vi- 
 
 triol is, to diffolve two ounces of Borax in a quart of water, gradually drop 
 into the folution one ounce of Oil of Vitriol, evaporate about one third of the 
 
 mixture, and then diftil and cohobate as before This Salt was firft difco- 
 
 vered by Mr. Homberg, and is ufed by the French phyficians in fevers and 
 ebullitions of the blood, in deliria, convuifions, hypochondriacal and hyfte- 
 
 rical. 
 
 half its weight of phlegm. It continues a 
 perfect Salt, and is by no means changed, 
 as Stahl fuppofes, to an earth. 
 
 Borax rendered fluid by fire, diflolves 
 molt kinds of earthy bodies and metallic 
 calces, more readily and more perfectly than 
 alcaline or other Salts: The molt compact 
 crucibles do not long fuifain its addon. Ne- 
 verthelefs a flight glazing with Borax is 
 faid to defend the vefi'el for fome time from 
 being corroded by glafs of Lead, as well as 
 by filling its pores to prevent the abforption 
 of any particles of metals melted in it. 
 
 The glades which Borax forms with 
 earths are in general very hard and com- 
 
 pact, and when newly prepared, of great 
 brightnefs and tranfparency. On long ex- 
 pofure to the air, they are apt, like Borax it- 
 felf, to become cloudy ; and if its proportion 
 is very large, opake. 
 
 {it) Makes Gold pale. ~\ This effedl is pre- 
 vented by the addition of Nitre or Sal am- 
 moniac, or the colour of the Gold reftored, 
 by rernel ting it with either of thole Salts — 
 I nave obferved likewife, that it renders 
 Brafs and Princes-metal pale, the Borax 
 acquiring a deep reddifh hue ; that it gains 
 a like colour on being melted with Copper, 
 and a darker blackifh from Iron. 
 
2 jo Bituminous Substances. 
 
 Bora x. rkal aflfeflions. Its particular nature is as yet unknown : It has no volatile 
 
 > fm ell, or pungent tafte, and appears to be of the neutral kind. 
 
 I have prepared this Salt by a more commodious method than that of Horn- 
 berg, without fublimation or diftillation. A folution of Borax being mixed 
 to laturation with a folution of Alum, the earth of the Ahum precipitates : 
 The remaining liquor evaporated to a certain pitch and fet to fhoot, yields fir ft 
 fine cryftals, the fame with the fublimed flow ers. If the procefs be continued, 
 
 the cryftals which fhoot afterwards are found to be of a different kind A 
 
 further account of Borax, and enquiries into its nature and properties, maybe 
 feen in Pott’s Obfervationes £2? animadverfiones chemic collect, ii. and ModeU’s 
 differtation de Bor ace native, a Perfis borech dpi a. 
 
 SEC T. IV. 
 
 BITUMINOUS SUBSTANCES. 
 
 Bitumens. TT"^ ITUMENS are inflammable mineral bodies, not fulphureous, or only 
 ' — Jr*^ cafually impregnated with Sulphur. T'hey are of various degrees of 
 confiftency, and feem in fome meaflure to correflpond in the mineral 
 kingdom, to the oils and refins of the vegetable. There is a perfectly fluid. 
 Naphtha. thin Bitumen, or mineral Oil, called Naphtha, clear and colourlefs as Cryftal, 
 of a ftrong lfnell, extremely fubtile, fo light as to fwim on all known liquors, 
 fpreading to a vaft furface on water and exhibiting rainbow colours, highly 
 inflammable, formerly made ufe of in the compofition of the fuppofed inextin- 
 petroleum. guifhable Greek fire. Next to this in confiftence \s the Oleum petra ox Petro- 
 leum ; which is groflfer and thicker than Naphtha , and of a yellowifh, reddifh 
 or brownifh colour, but very light, fo as to fwim even on Spirit of Wine. By 
 diftillation, the Petroleum becomes thinner and more fubtile, a grofs matter 
 being left behind : It does not eafily arife, nor does it totally lofe its colour by 
 this procefs, without particular managements or additions. 
 
 Their natural Both Naphtha and Petroleum are found plentifully in fome parts of Perfia, 
 halory. trickling through rocks, or fwimming on the furface of waters. Ktempfer 
 gives an account of two fprings near Baku, one affording Naphtha, which it 
 receives in drops from fubterraneous veins, the other, a blackifh and more 
 fetid Petroleum, which comes from mount Caucafus •, the Naphtha is collected 
 for making varnifhes ; the Petroleum is received in pits, and fent to Sja- 
 machia, Baku, Media, Hyrcania, Ufbeck, Circafiia, and Dageftan, for 
 lamps and torches : From this place alone are faid to be exported daily eight 
 or ten thoufand batmans, each batman amounting to about nine Dutch pounds. 
 A further account of the bituminous tracts in that part of the world, and of a 
 burning land, F J>c. may be feen in the author above-mentioned, and in the 
 
 Breflau 
 
Bituminous Substance s, 231 
 
 Breflau collections. Native Petrolea are found likewife in Italy, particularly Bitumens. 
 in Lombardy and the Modenefe ; and an inferior fort, of a ftrong difagree- ' — “” v ~“ — ? 
 able fmell, and fharp bitter tafte, at Gabian in Languedoc : Aliace, Neu- 
 chatel, and feveral other places in Europe afford alfo Petrolea. Some years 
 ago, a bituminous earth and Petroleum were difcovered in the Electorate of 
 Hanover. In the (hops we meet with no genuine Petrolea ; what is lold under 
 the name both of white and red Petroleum, being an artificial compofition, 
 confiding chiefly of the oil of the pine-tree, drawn over perhaps from b; icks 
 after the fame manner as the Oleum philofophorum , or diftilled in an open fire 
 without addition. The Dutch fell us an Oleum terra, as it is called, of 
 a ftrong fmell, and tranfparent reddifh brown colour, brought in large 
 earthen jars from the Eaft Indies, and faid to be ufed there in palfies : even 
 this however does not feem to be a native Bitumen, any more than the officinal 
 Oleum petra. The officinal fort, diftilled from bricks, greatly refembles it. 
 
 The true Naphtha is recommended againft diforders of the nerves, old pains, 
 cramps and contractions of the limbs, for difcuffing tumours, &c. 
 
 There are Bitumens of a middle confidence betwixt fluid and lolid ; as that Thick Bita* 
 called in England Barbadoes Tar, faid to drop from certain rocks in America. n ' ens " 
 
 A thick adhefive Bitumen of this kind is plentiful in Auvergne in France, and 
 proves rather incommodious than ufeful : it exudes on the iurface of the earth, 
 dicks to the feet like pitch, and is there called Devil’s dung. Such alfo is the 
 Bitumen judaicum , which is found on the furface of the dead lea, and faid to 
 be raked off by the neighbouring inhabitants before it has been hardened by 
 the fun. 
 
 There are fundry Bitumens perfectly dry and folid, as Amber, Ambergris, Solid 
 Pit coal, Jet. In the Prufiian Pomerania we have a bituminous earth, which msns * 
 proves an excellent fuel, eafily taking fire, burning long, yielding no un- 
 pleafant or prejudicial but rather an agreeable fmell fomewhat like that of 
 Arfiber, and leaving only a fmall quantity of perfectly whice afhes. Turf and 
 Pqat belong alfo to this clafs, as being chiefly a bituminous earth, and yield- 
 ing, when firft fet on fire, a difagreeable bituminous fmell; though originally 
 compofed in great part of the roots of vegetables (x). The learned Dr. Deg- 
 
 ner 
 
 (jc) Peat.] There are very confiderable dif- 
 ferences in Peat, proceeding perhaps wholly 
 from different mineral admixtures, for the 
 fubftance of the Peat is plainly of vegetable 
 origin, whence it is found to anfwer for 
 the fmelting of ores, and the reduction of 
 metallic calces nearly in the fame manner 
 as the coals of wood. Some forts yield in 
 burning a very difagreeable fmell, which 
 extends to a great diftance ; whilft others 
 are inoffenfive. Some bum into grey or 
 white, and others into red ferrugineous 
 afhes. The afhes yield, on elixation, a fmall 
 quantity of alcaline fait, with fometimes one 
 andfometimes another faltof theneutralkind. 
 
 The fmoke of Peat does not preferve or 
 harden flefli like that of wood j and the 
 
 foot, into which it condenfes, is more dif- 
 pofed to liquefy in moift weather. On di- 
 ftilling Peat in clofe veffels, there arifes a 
 clear infipid phlegm, an acid liquor which 
 is fucceeded by an alcaline one, and a dark 
 coloured oil. The oil has a very pungent, 
 tafte ; and an empyreumatic fmell, lefs 
 fetid than that of animal fubftances, 
 more fo than that of the mineral bitumens : 
 it congeals in the cold into a pitchy mafs, 
 which liquefies in a fmall heat : it readily 
 catches fire from a candle, but burns lefs 
 vehemently than other oils, and immedi- 
 ately goes out upon removing the external 
 flame : it diffolves almoft totally in recti- 
 fied fpirit of wine into a dark biowniffi red 
 liquor. 
 
232 Bituminous Substances. 
 
 Bitumens. ner of Ntmmagen has written an exprefs treatife on this fubjeft, to which I 
 -v — — > refer. Sea-water and certain fprings are likewife impregnated with bituminous 
 matter, as we (hall fee hereafter in treating of water. 
 
 L AMBER. 
 
 Amber. AMBER Succinum , called by the Greeks EleRrum , and by the Arabians 
 > — . j — j Carabe from its power of attra&ing ftraw and other light bodies when 
 rubbed, is a folid Mineral Bitumen ; not as fome have fuppofed, a vege- 
 table refin, or infpiflfated juice, introduced into cavities in the earth, and there 
 indurated and fomewhat changed in its quality; nor a true marine produ&ion, 
 though fometimes found in thefea. 
 
 Its natural It is met with plentifully in regular mines in fome parts of Pruflia : the 
 hiilory. upper furface is compofed of fand, under which is a ftratum of loam, and un- 
 der this a bed of wood, partly entire, but chiefly mouldered or changed into 
 a bituminous fubftance : under the wood is a ftratum of vitriolic or rather alu- 
 minous mineral, and under this another bed of fand, in which the amber 
 is found. Strong fulphureous exhalations are often perceived in the pits. 
 Helving relates, that wherever there is Amber, there is always a bituminous 
 earth and foffil wood, a gravelly matter, Vitriol, Nitre, and Sulphur ; and 
 that the matter of the Amber refides in the foflil wood. The oblervation ap- 
 pears to be juft, except in regard to Nitre, which is never found in the Amber 
 pits ; fome aluminous matter was doubtlefs miftaken for Nitre. Confiderable 
 quantities are met with all'o in the fea near the Amber fhores, particularly after 
 a fcorm ; the fea having probably wafhed out the mineral from the earth. 
 
 The principal Amber pits are in the territory called Sandlande, between 
 Pillau and Fifchhaufen, near the villages Grosfhubenick, Grofsdirfchken, War- 
 nicken, Strobfchner, Rittener, Palmnick, &c. The fhores on which Amber 
 is chiefly Allied for are thole called Krecke, Nodens, LafTnick, Knick, Kra- 
 pellen, Krackftepellen, Crimichen, and Thiefkim or Brufterort. The man- 
 ner of fifhingfor it is pretty well defcribed in Hartmann’s Hijloria Succini Prujfici. 
 The digging of Amber is a very dangerous work ; the ground not being ftony 
 or rocky as in metallic mines, but Tandy or loamy, and hence very fubjeft to 
 fall in when hollowed underneath. His Pruflian Majefty receives a large an- 
 nual revenue from this commodity ; he has a peculiar council called the Am- 
 ber-chamber *, and no one but thofe appointed for that purpofe is permitted 
 to dig or fifli for Amber in his dominions — Small quantities of Amber are 
 met with alfo in fundry other places ; in Bohemia, Silefia, Saxony, Hungary, 
 France, &c. The pieces of Amber now and then found in thefe places were 
 not, perhaps, originally produced, but left there by the flood. 
 
 Subftances in- Various kinds of fubftances are often inclofed in maiTes of Amber; as drops 
 doled in it. 0 f water, which fall to this fide and that upon moving the mafs ; fmall bits 
 of wood, mofs, leaves of plants, &c. a variety of infe&s, particularly gnats, 
 flies, fpiders, ants, moths, butterflies, grasiboppers, bees, worms, cantharides, 
 caterpillars, crickets, maggots, lice, and fleas. There are reports alfo of 
 frogs, vipers, fifhes and other large animals being found in mafTes of Amber, 
 and fuch are figured in Mercatus’s Met allot beca ; but moft of thefe are artificial 
 3 pre= 
 
Bituminous Substances, 233 
 
 preparations: even the fifb in Amber, in his Pruffian Majefty’s repofitory, is Am b e r 5 
 manifeftly fa&itious. In my own pofieffion there are two hundred fpecimens c— v— 
 of Amber, every one of which has fomething inclofed. It is evident from 
 hence, that this Bitumen has once been in a fluid ftate ; though we cannot 
 conclude that it ever was a liquid or oily matter, and acquired its confiftency 
 an3 folidity by degrees. Appearances are rather contrary to this fuppofltion. 
 
 The infedts found in Amber have nothing of thofe drained or diftorced pof- 
 tures which animals are naturally thrown into upon endeavouring to difengage 
 themfelves when entangled ip a vifcous liquid. We often fee pieces of Am- 
 ber in which there are perfect flies with the wings and feet beautifully ex- 
 panded as if they were (till flying. It is moft probable, that the Amber Produced 
 was generated inftantaneoufly from the concourfe of mineral oil or petroleum Pom Petrole- 
 with vitriolic acid, in the form of vapours ; which at once concreted together, acid'**”' 
 and embalmed the infefits that happened to lye in their way, with a more dur- 
 able and precious covering than has ever fallen to the lot of the moft magni- 
 ficent monarchs. A bituminous wood is to be conflantly met with in the 
 
 Pruflian Amber pits : This however, does not appear at all necefiary to 
 the formation of Amber. Amber is found in Italy ; where there is no foil'd 
 wood, but plenty of mineral oil or petroleum. 
 
 There are different forts of Amber in regard to external appearance ; opake Different 
 and tranfparent; white or whitifh, yellowilh or yellow, greenilh, brownifh, forts, 
 bluifh, reddifh, or brownifh red : what is called black Amber is no true 
 Amber, but a bitumen of the Pit-coal, afphaltum or jet kind. Some divide 
 Amber into native and factitious : I have leen artificial mafies indeed refem- 
 bling Amber in appearance •, but no true Amber has hitherto been produced 
 by art. In Holland a vegetable refin, whofe proper name is Gummi de Loock, fophifticated 
 is fold under the name of American Amber: this, when in confiderable' vith a vege- 
 maffes, and by itfelf, is eaflly diftinguifhed from the genuine Amber, by its tabIe reftn - 
 having lefs electricity, wanting the peculiar ftrong fmell which Amber emits 
 in burning, by its greater folubility in fpirit of wine, and not yielding the 
 fame principles as Amber in diftillation : Small pieces of the refin mixed 
 among true Amber are more difficultly difcovered, and this abufe is not un- 
 frequently praCtifed. 
 
 Amber is divided by the workmen into different fortments according to the Natural dif- 
 fize of the mafies ; the fmalleft and coarfeft bits are called Sandfiein , the fome- ferences> 
 what larger, Schlug ; thofe which are ftill larger, Firnifs , or Varniffi Amber; 
 the pieces which are large enough to be turned into beads, or other orna- 
 ments or utenffls, are named from the works for which they are judged to be 
 fit. There are other divifions taken from the quality of the mafies. Of the 
 opake Ambers, the moft valuable is the flaky or fcaly ; next to this, the un- 
 dulated or waved ; and next in order the cloudy, the cauliflower or pearl like, 
 the milky, the citron yellow, the wax-coloured, the dark yellow, the 
 brownifh, and the dark brown, which laft is the coarfeft of all. The tranf- 
 parent Ambers are divided into reddifh, gold yellow like a yellow glafs, ci- 
 tron yellow, pale yellow, and whitifh. Of all thefe there are feveral fub- 
 divifions, commixtures, or intermediate Guides ; and fometimes we meet with 
 pieces of other colours, as greenilh, bluifh, coffee coloured, opal coloured, &c. 
 
 PI h With 
 
234 - 
 
 B I T U M I N O’ IT 3 S'UBS T A N 1 ' C E S„ 
 
 Amber. With regard to the transparent Ambers, it may be proper to take notice; 
 
 i. That infedts or other foreign bodies are obferved chiefly in thefe; pofllbly 
 they may often be lodged alio in opake Amber, though the opacity of the 
 Embellifhed mai's prevents our feeing them. 2. That opake Amber is capable of being, 
 by art. made tranfparent by art ; and hence that all our Tranfparent Ambers were 
 
 not naturally fuch. 3. That the fine gold yellow tranfparent fort is entirely 
 natural; the common methods of improving the transparency, weakening 
 the "xflour. There are means of communicating to Amber a variety of co- 
 lours : An excellent artifl at Breflau, by name Gottlieb Samuelfon, not only made 
 opake Amber tranfparent, but tinged it red, blue, violet, of a purplifh, green, 
 and white •, and cut it into brillants, necklaces, ear-pendents, bracelets, 
 in imitation of precious ftones •, as alfo into fpedcacies, microfcopes, prifms, 
 burning lens’s, of which an account may be feen in the Breflau colledtions. 
 4. That Amber clarified by art is always harder, and Jefs eledtric, than in its 
 natural untranfparent (late. 
 
 Clarification. Schroder relates, that yellow A^mber is made white by boiling in fait-water; 
 
 and later writers have copied this account : On trial, however, fait- water is 
 not found to have any fuch effedt. The workmen have two methods of cla- 
 rifying Amber : One by furrounding the Amber with Sand in an iron pot, 
 and cementing it with a gradual lire for forty hours ; fome ftnall pieces placed 
 near the fides of the veffel, being occafionally taken out forjudging of the 
 effedi- of the operation : The fecond method, which is that nioft commonly 
 pradifed, is, by digefiing and boiiing the Amber about twenty hours with 
 Rapefeed oil, by which it is rendered both clear and hard : Treated in the 
 fame manner with Linfeed oil, it does not become clear. Sendelius informs us 
 tdrat he clarified pieces of cloudy Amber, by applying them to the flame of a 
 candle, and rubbing them now and then with tallow ; and that opake pieces, 
 boiled with fifh and with flefti, (hewed adifpofition to become clear. The moft 
 defirable point in the manufadures of Amber would be, to find a method of 
 melting finall pieces into a large one ; but nothing of this kind has hitherto 
 been diicovered. 
 
 Enquiry inro It is no fmall piece of art to procure a total folucion of A-mber. I have 
 folrentsfor it. tried twenty-five different methods; with alcalies, acids, oils, inflammable 
 fpirits, dulcified fpirits, balfams, and other menftrua ; without being able 
 perfedly to fucceed. Hoffmann relates, that he has diffolved Amber in two 
 ways: One is by putting two parts of oil of Almonds and one of powdered 
 Amber into a glafs veffel, and fetting the veffel in Papin’s digefter filled about 
 one third with water : The cover of the digefter being ftrongly fecured, and 
 a moderate fire kept up for above an hour, the Amber was refolved into a 
 tranfparent gelatinous mafs, on the furface of which floated a little fluid oil. 
 The other method is by boiling powdered Amber in water, with an equal 
 weight of cauftic Nitre ; this corrofive alt ali oceafioning, he fays, altnoft all 
 the Amber to be diffolved. Thefe experiments I leave to their own merit, 
 but muft obferve, that neither of them afford fuch lokitions as I was in fearch 
 of. Henckel has carried the affair much farther, pretending to prepare Am- 
 ber, without burning, and without alcalies, fo as to diffolve totally in Spirit 
 of Wine : Of this aifertion we can form no judgment till the fadt is produced, 
 
 / " Of. 
 
Bituminous Substances, 235 
 
 Of the common menftrua, there is not one which totally diftqlves this con- A m b e r* 
 crete: In Papin’s digefter, the Amber perhaps is only foftened. Mod li- C- — 
 quors however extradt fome portion of it : A tindlure made in vinous fpirits 
 is kept in the fhops. Some have thought to promote the addon of the fpirit 
 by fixed or volatile alcaline falts : But thefe kinds of additions give very little* 
 if any, aftiftance to the fpirit as a menftruum, and are accompanied with an 
 inconvenience of rendering the tindture unfit for the chirurgical ufes to which 
 it is commonly applied. Highly redlified Spirit of Wine extracts of-itfelf a 
 fufficiently flrong tindture from Amber: The admixture of alcaline halts 
 deepens the colour of the liquor, without increafing the quantity taken up. 
 
 If the Ample tindture is required to be more faturated with the Amber, it may 
 be eafily rendered fo by drawing off a part of the fpirit, which may be re- 
 ferred for the like ufes again, as being impregnated with the more fubtile 
 parts of the Amber. If the fpirit be totally abftraded, a balfamic or refinl- 
 form extrad is left : This is employed by fome as an ingredient in compo- 
 fitions for pills. Water mixed with the tindure renders it turbid, but fcarce 
 any precipitation enfues ; though in feveral books of pharmacy a magiftery of 
 Amber is direded to be prepared by this means. 
 
 Amber melts and burns in the fire, and emits a ftrong peculiar fmeli. Bi- DilUUstioh. 
 Hilled, in a ftrong heat, it yields a phlegm, an oil, and a particular fpecies of 
 volatile faline matter. The diftillation is performed in earthen or glafs re- 
 sorts, frequently with the addition of Sand, powdered Flints, Bricks, Lime, 
 elixated Allies, Bole, Loam, Pumice, Sea-falt, Coals, (Jc. Confiderable dif- 
 ferences are obferved in the produds according to the additions made ufe of : 
 
 With fome the Salt proves yellowifh and dry, with others, brownifh or 
 blackifh, and unduous or foft like an extrad : With fome the oil is through- 
 out of a dark brown colour ; with others it proves externally green or greenifh^ 
 with elixated allies in particular, of a fine green, as I have found on repeated 
 trials. The quantity of oil and phlegm is greateft when coals, that of Salt 
 when Sea-falt is ufed. The moll common addition is fand -, of which two 
 parts are mixed with two or one of Amber in coarle powder, the mixture put 
 into an earthen retort, of which it may fill fomewhat more than one half, the 
 neck of the retort wiped clean, the veffel placed in a reverberatory furnace, a 
 receiver luted on fo as that the neck of the retort may reach down into its 
 body, and the fire cautioufly increafed, left the Amber, melting like pitch, 
 fnould boil over into the recipient : At firft a phlegmatic liquor difiils, then 
 a fluid oil, afterwards a thicker and more ponderous, and laft of all, an oil 
 ftill more ponderous along with the Salt. Amber may be very commodioufiy 
 diftilled alfo without any addition, in glafs retorts coated or uncoated ; only 
 greater caution is here required in the management of the fire, as the Amber 
 is more apt to fwell up and boil over by itielf, than when divided by earthy 
 or other matters: The recipient fnould be large, and the retort only half 
 filled with the Amber. Thofe whofe foie bufinefs it is to diftil Amber in 
 Pruffia, and whom long experience has taught the mod advantageous methods 
 of doing it, ufe no addition. The Englifh chemifts likewife diftil their Am- 
 ber without addition, and fell the refiduum to the japanners, who prepare 
 from it the fineft black varnifh. Hoffmann directs Amber-varnifh to be 
 
 H h 2 made 
 
236 Bituminous Substances. 
 
 Amber, made by melting the Amber and pouring it on an iron plate, then pulve- 
 — v— — ' rizing, and putting it into a crucible, adding Lin feed oil that has been pre- 
 pared with litharge, and iaftly pouring in Oil of Turpentine till the whole is 
 diffolved : The English method of making varnilh from the Caput morimm 
 is certainly more frugal than the melting of good Amber on purpofe. The 
 Caput mortuum of Amber diftilled per fe was in my experiments confiderably 
 light and fpongy : When it looks like Colophony, we may prelume that there 
 has been fome mifmanagement in the procefs ; that either the fire has been too' 
 haftily railed at firft, or not fufficiently continued. 
 
 In order more perfe&ly to colled the Salt, which is the moft valuable pro- 
 duel in this operation, the Pruflian workmen frequently change the receiver 
 during the diftillation, and keep apart the phlegm and the light oil which 
 arife at firft. They purify the Salt by placing it for a time upon bibulous 
 paper, which ablorbs a part of the oil •, and changing the paper fo long as 
 it receives any oily ftain. Where a further depuration is required, (for by this 
 method we feparate only a part of the oil that adheres externally) the Salt is 
 to be leraped out as clean as poffible from the neck of the retort, or wherever 
 elfe it has concreted, and wafhed off with water. The whole diftilled matter 
 Is then to be mixed with a confiderable quantity of hot water, the mixture 
 well fiirred together with a wooden fpatula, the water, after fettling, poured 
 off, and frefin parcels of hot water added, to extract all the laline matter that 
 may be retained by the oil : The Salt feparated at firft is to be diffolved in 
 this liquor, the folution filtered, evaporated in glafs veffels to a proper pitch, 
 and then fet in the cold : The Salt will fhoot into fine fpongy yellow cryftals, 
 which may be gently dried upon bibulous paper : The remaining liqnor may 
 be further infpififated and cryftallized afrefh, or evaporated to drinefs : The 
 Salt obtained by thefe lafb proceffes will turn out browner and browner, and 
 is therefore to be referved for inferior purpofes, or further purified, by re- 
 peating the folution, filtration, and cryllallization. I have freed the Salt, by 
 v/ay of curiofity, fo far from its oil, that it looked white as fnow. 
 
 Salt of Amber, though it arifes in diftillation, and is diftinguiflied by the 
 name of a volatile Salt, is not to be confounded with the volatile Alcalies. It 
 is truly an acid Salt, changes Syrup of Violets red, effervefees with and neu- 
 tralizes alcalies, and precipitates fubftances diffolved in them. The liquor 
 cornu cervi fuccinatus of the ftiops is no other than a neutral faline liquor cora- 
 pofed of this Salt and volatile alcalies : The method of preparing it in the 
 greateft perfection is, to difiolve pure Salt of Amber and Salt of Hartfhorn fe- 
 parately in diftilled water, and add the alcaline folution to the other by a little 
 at a time, till the faturation is compleated : By this means we obtain a neutral 
 ammoniacal Salt of a peculiar kind. The nature and qualities of Salt of Am- 
 ber are as yet very little known. Its acid feems to approach neareft to the 
 vitriolic; lor Oil of Vitrioi, which expels the nitrous, marine, and acetous 
 acids in form of fumes from alcalies or earths with which they have been com- 
 bined, extricates no vapour from Salt of Amber, nor from combinations of 
 H with alcaline Salts. When fixed alcalies however have been neutralized 
 with Salt of Amber, and reduced into cryftals, they ftill effervefee with the 
 vitriolic acid ; which, if the acid of Amber was truly vitriolic,, they could 
 
 not 
 
Bituminous Substances. 
 
 not do (jy). We very rarely meet with any genuine Salt of Amber in the A m 
 fhops ; powdered Amber, Creme of Tartar, Sugar, Sal ammoniac, Sea-falt — 
 and other fubftances, being commonly mixed with it, and a good cpaantity of 
 oil left in it, the better to conceal thele additions. 
 
 The' 
 
 ( y ) Salt of Amber.} Though Oil of Vi- 
 triol unites with this acid Salt without effer- 
 vefcence or fumes, it does not follow that 
 its acid is of the vitriolic kind. Oil of Vi- 
 triol, dropton Tartar, is imbibed with equal 
 quietnefs, yet no one prefumes from hence, 
 that the acid of Tartar is vitriolic .... 
 Mr. Bourdeline endeavours to prove, that 
 the acid of the Salt of Amber is marine*. 
 A genuine Sea-Salt is indeed obtainable 
 from fome forts of Amber, as 1 have oftener 
 than once oblerved ; but this does not affebt 
 the volatile Salt of the Amber, the Sea-falt 
 being equally procurable after the feparation 
 of the volatile Salt, and the volatile Salt 
 giving no marks of any thing marine. As 
 large quantities of this Bitumen are found in 
 the fea, we need not be at a lofs to account 
 for its accidental impregnation with marine 
 Salt .... Mr. Pott f has given a curious 
 fett of experiments upon this fingular Salt ; 
 from which its acid appears plainly to be 
 efi'entially different from the three mineral 
 acids, and to approach neareft to thofe or 
 the vegetable kingdom. We fhall here 
 give an abftrabt of the principal obiervations 
 he has made upon this Salt. 
 
 Salt of Amber requires a large quantity of 
 water for its lolution. In the firft cryftalli- 
 zation itfhoots into fpongy flakes, in colour 
 refembling brown Sugar-candy : The 
 
 cryftals which fucceed prove darker and 
 darker coloured. On repeating the depu- 
 ration, the firft cryftals appear at top of a 
 clear yellow or whitifh colour, in form of 
 long needles or feathers ; at bottom darker 
 and more irregular, as are likewife the cry- 
 ftals which ftioot afterwards. The cryftals 
 neither liquefy nor become powdery in the 
 air: Rubbed, they emit a pungent lmell 
 like that of radifhes, efpecially if warmed 
 a little ; their tafte is acid, not in the leaft 
 corrofive, but with a kind of oily pungency. 
 
 This Salt kept in the heat of boiling 
 water lofes nothing of its weight, and fuffers 
 no alteration. In a great heat it melts like 
 oil ; after which, a little oily acid liquor 
 * Mem. de l’acad. de Sciences de Paris. An. i 
 i Mem. de l’acad. de Sciences de Berlin. An. 
 
 arifes, then oily ftriae appear in the lower 
 part of the retort, and the Salt fublimes into 
 the neck, partly in the form of a dark yel- 
 low butter, and partly in that of feathers, a 
 black coaly matter remaining at the bot- 
 tom ; fo that by this procefs a part of the 
 Salt is deftroyed. 
 
 Oil of Turpentine has no abtion on this 
 Salt. Highly rebtified Spirit of Wine gains 
 from it a yellow colour in the cold, and on 
 the application of heat diflolves a consider- 
 able quantity, but depofites great part of it 
 on cooling : The Salt thus depofited is 
 fomewhat whiter than before, but Hill con- 
 tinues fenftbly yellow. The dulcified or 
 vinous Spirit of Sal ammoniac diflolves it 
 readily, without effervefcence, into a yellow 
 liquor: If the Salt was foul, the lolution 
 proves of a red colour: On burning oft' the 
 vinous fpirit, a neutral liquor remains. 
 
 A folution of Salt of Amber in water, fa- 
 turated with a pure fixed alcaline Lixivium, 
 yielded on infpiflation a faline matter, which 
 would not cryftallize, and which, when ex- 
 ficcated by heat, deliquiated in the air, leav- 
 ing a considerable portion of an unbluous 
 earthy matter : Being again gently infpif- 
 fated, it left a brownifh Salt, very foluble, 
 weighing one half more than the Salt of 
 Amber employed : This Salt effervefeed 
 with the nitrous and vitriolic acids : The 
 vapour which exhaled was not acid, but 
 fomewhat fulphureous and oily. On repeat- 
 ing the experiment, and fully faturating the 
 Alcali with the Salt of Amber, the neutral 
 Salt made no effervefcence with thofe acids. 
 This Salt did not perfebtly rnelt before a* 
 blowpipe : Continued in the fire for fome 
 time, it effervefeed with Aqua fortis, a mark, 
 that it had now loft fome of its acidity. In 
 diftillation it yielded a bitter oily alcalefcent: 
 fpirit, much refembling the Spirit of Tar- 
 tar ; and towards the end an empyreu- 
 maric oil : The refiduum elixated, yielded 
 
 the alcaline Salt a^ain of a brown colour. 
 
 O 
 
 Salt of Amber mixed with volatile Spirits, 
 raifes a ftrong effervefcence, and after fuffi- 
 74 2. 
 
 *753.- 
 
 237 
 
 B E’Ro- 
 
 c;encr 
 
238 ' Bituminous Substances. 
 
 Amber. The Oil of Amber is reitified by diddling it over, either by itfelf, or with 
 ; 1 different additions,. as burnt Bones, Lime, elixated A (lies, Chalk, tobacco- 
 
 Oil. pipe Clay, Potafh, 0c. The bed method is to didili it with common water, 
 
 and 
 
 dent faturation, forms with them a neutral, 
 ammoniacal, oleaginous Jiquor ; which to- 
 tally arifes in diftillation in a fluid form, ex- 
 cept that a fmall portion of a penetrating 
 oily faline matter concretes towards the end. 
 
 On diftilling Salt of Amber with an equal 
 quantity of common Sal ammoniac, an acid 
 •marine fpirit came over, of a very ftrong 
 •i'mell, and a brown colour: Afterwards a 
 little white Sal ammoniac fublimed : At 
 length arofe fuddenly a large quantity of a 
 fuliginous or bituminous matter, leaving be- 
 hind a fmall portion of a like filming black 
 fubftance. The coaly matter was' confider- 
 ably more in quantity than the Salt of Am- 
 ber employed On treating it with Nitre, 
 
 red nitrous vapours arofe, and then the 
 
 mixture detonated with violence A 
 
 1 mixture of it with Borax frothed and fwelled 
 up much more than Borax by itfelf, and on 
 raifing the fire, yielded only fome oily drops ; 
 
 ■ the acid being deftroyed by this Salt, as by 
 jfixt Alcalies and Quick-lime, 
 
 Spirit of Sea-falt poured upon one fourth 
 its weight of Salt of Amber, made fcarce 
 any folution in the cold : On the applica- 
 tion of heat, nearly the whole coagulated 
 into the confiftence of a jelly. In diftilla- 
 tion the Spirit of Salt arofe firft, then almoft 
 the whole of the Salt of Amber, partly like 
 firm butter, partly like long ftriated plum- 
 ous Alum, very pure, and of a fine white 
 colour, its oily matter being changed into a 
 coal at the bottom. The Salt thus puri- 
 fied, makes no precipitation in folution of 
 Silver, and confequently retains nothing of 
 the marine acid, nor does it precipitate folu- 
 tion of Quick-lime made in Spirit of Salt, 
 and confequently contains nothing vitriolic. 
 If any of the mineral acids was contained in 
 this Salt, it could not here efcape difcovery ; 
 the oil, which in the rough Salt is fuppofed 
 to conceal the acid, being in this procefs fe- 
 parated. 
 
 Aqua fortis poured upon one fourth its 
 weight of Salt of Amber, extracted a yel- 
 lowifh colour in the cold, but diflol ved little : 
 On the application of heat, the whole dif- 
 folves into a clear liquor without any coa- 
 gulation : If the Salt is very oily, the folu- 
 
 tion proves red. In diftillation, greateft 
 part arifes in a liquid form, with only a fmall 
 matter of concrete Salt. The fpirit does 
 not ait upon Gold, but diftolves Silver and 
 Quickfilver as at firft; a proof, that it has 
 received no marine acid from the Salt of 
 Amber. 
 
 Oil of Vitriol being added to twice its 
 weight of Salt of Amber diluted with a little 
 water, a moderate fire elevated an acidu- 
 lous liquor, which appeared to proceed from 
 the Salt of Amber; for its making no 
 change in folution of fixed Sal ammoniac 
 fhewed it not to be vitriolic. On continu- 
 ing the diftillation by a ftronger fire, greateft 
 part of the Salt arifes undeftroyed, and the 
 oil of Vitriol along with it, a black, light, 
 porous earth remaining. 
 
 Equal parts of Quick-lime and Salt of 
 Amber gave over in diftillation only an aci- 
 dulous phlegm : The reftduum, elixated 
 with water, yielded a folution of the Lime 
 in the acid of the Amber, refembling a fo- 
 lution of the fame earth in vegetable acids, 
 precipitable by alcaline Salts and by the vi- 
 triolic acid. Lime adde. I to a watery folu- 
 tion of Salt of Amber, diftolves with fome 
 effervefcence, after which the whole coagu- 
 lates into the confiftence of a jelly: This 
 diluted with warm water, proves fimilar to 
 the foregoing folution. 
 
 Solution of Salt of Amber makes no preci- 
 pitation in folutions of Silver or Quickfilver. 
 It diftolves Zinc, as all acids do : Fixed Al- 
 calies precipitate the Zinc:, The volatile do 
 not, and when a fufficient quantity of the vo- 
 latile has been added, the fixed make no pre- 
 cipitation. It aits exceeding flowly and diffi- 
 cultly upon Copper, but corrodes calcined 
 Copper in a fhorter time. It foon corrodes 
 Iron, by coition, into a Crocus, and dif- 
 folves a part into a liquid form : The folu- 
 tion has little colour, but alcaline Salts rea- 
 dily difcover that it holds Iron, by rendering 
 it turbid and whitifh, and throwing down a 
 confiderable quantity of a greenifh calx. A 
 folution of this Salt does not appear to ait 
 upon Lead or Minium by long digeftion ; 
 and in this refpeit it difters from the vege- 
 table acids. 
 
Bituminous Substances. 239 
 
 and repeat the diftillation feveral times with frefn parcels of water: By this A mber, 
 
 method we obtain a clear limpid oil, a large quantity of thick pitchy matter '*~~~Y a ***J 
 
 remaining behind. I have redtified Oil of Amber to fuch a degree, that fcarce 
 
 any one could tell what kind of fluid it was, as it mingled with water, with 
 
 Spirit of Wine, with an acid, with expreffed oils, with diftilled oils, and al- 
 
 moft with all liquors. Spirit of Wine digefted with the unre&ified oil, does 
 
 rot diflolve it, but extracts fome of its finer parts, leaving a confiderably 
 
 thick pitchy fubftance In the fliops it has been cuftomary to impregnate 
 
 volatile fpirits with Oil of Amber, by mixing powdered Amber with the in- 
 gredients from which they are diftilled : Commonly one part of Amber, one of 
 Sal ammoniac and three of Quick-lime, are mixed together, and committed 
 to diftillation with a proper quantity of Spirit of Wine. Thefe fuccinated spi- 
 rits of Sal-ammoniac, or Sal volatile oleofum fuccini, may likewife be made extem- 
 poraneoufly, by difl'olving redtined Oil of Amber in the vinous Spirit of Sal 
 ammoniac prepared with Quick- lime. 
 
 Different forts of Amber differ greatly in the produce of Salt and Oil. Quantities of 
 Sixteen ounces of the common coarfe untranfparent Amber found in the fea (the Salt and -Gil, 
 fort generally made ufe of in the fliops) yielded fomevvbat more than eleven 
 ounces and fix drams of Oil, four drams and a half of Salt, nearly an ounce 
 and a half of water, and fcarcely an ounce of Caput mortuum. Hartman relates, 
 that white Amber yields more Salt than the yellow ; that from a pound of the 
 firfthe obtained four drams, and from the fame quantity of the latter only one. 
 
 Another Pruftian obferves, that the Sandjiein yields molt Salt, the Schlug lefs, 
 and the Fernifs ftill lefs. I am informed by a friend, that from a pound of the 
 Sandjiein he has gained from fix drams to an ounce of Salt ; but I prefume the 
 Salt was either very oily, or was diftilled with additions. I repeated the ex- 
 periment on that kind of Amber with great care, and obtained from thirty-two- 
 ounces, nine drams of good pure Salt, and nearly twenty-four ounces of Off. 
 
 II. A M B B R G ■ R I S. 
 
 ^MBERGRIS, Ambragrifea , is a marine Bitumen, about the confiftence^ MBERG „ IC 
 of wax, of a laminated ftrudture, as if the mats was formed by a fucceffive i — ' J 
 appofition of matter, fometimes found in the waters of the fea, fometimes Natural luf- 
 thrown out upon the ihores, and fometimes met with in the ftomachs 
 whales and other fifties, frequently intermixed with little bones, claws of birds 
 and otherlike matters. Thefe circumftances have given rife to many ridicu- 
 lous opinions concerning its origin, as its being the excrement of birds or 
 fifties, generated in the ftomachs of fifties like Bezoar, being a lbrt of wax pro- 
 duced by bees upon rocks, &c. 
 
 The greateft quantities of Ambergris are met with in the Eaft-Indies, about 
 the ifland Madagafcar, the Molucca, ifiands Mauritius and Neykotarres, the 
 weftern Sumatra iftands, about the ifland Borneo and Cape Commorin near Ma- 
 labar, and on the Ethiopian coaft, . which, from Solafa to Brana, is faid to be 
 very rich in Ambergris, Pieces are fometimes met with of an extraordinary Ex'traordf- 
 fize. Chevalier and Garcias mention a piece weighing no lefs than three thou- nary pieces, 
 fand pounds, found in 1555 at Cape Comorin, and fold for Afphaltum ; and 
 
24-0 
 
 Bituminous Substance s. 
 
 Ambergris. Job. Hugo von -Lindfchott informs us, that a mafs of thirty quintals was 
 ■' found at the fame Cape. Monardes and Francilcus Hernandez mention a 
 piece of an hundred pounds; Garcias, one as large as a man, and another 
 which was ninety palms in length and eighteen in breadth ; Montanus, one of 
 a hundred and thirty pounds; andKempfer, one exceeding that weight, found 
 in his time in the province of Kinokuni in Japan. The Dutch Eaft-India 
 company purchafed of King Tidori in 1 693, foreleven thoufand rixdollars, a 
 piece of Ambergris weighing one hundred and eighty -two pounds, which was 
 kept many years at Amflerdam, and feen by thou lands, but afterwards broken 
 and fold by piece-meal : It was of the fliape of a tortoife, and meafured five 
 foot eight inches by two foot two: Nicholas Chevalier has given a particular 
 aefcription of it in a treadle printed at Amflerdam in 1700. Mr. Godfrey, a 
 chemift in London, informed me that a merchant there had a mafs of fix hun- 
 dred ounces, and that another had one of fixty pounds. 
 
 Differences. Ambergris is of various colours, afh-coloured, whitifh, yellowifh, blackifh” 
 grey, brown, black, {freaked and fpotted. The pieces which have been 
 fwallowed by fifhes are the lead efteemed, as receiving an ill fmeil from the 
 animal. The quite blackifh and the quite whitifh are to be rejected ; and thofe 
 which are fmooth and of an uniform texture, we may fufpebt of being coun- 
 terfeits. The afh-grey-coloured Ambergris, with whitifh, blackifh, and yel- 
 lowifh ftreaks or fpecks, is accounted the befl, efpecialiy when intermixed 
 General pro-with beaks of birds, bits of cuttle- bone, or other like matters; not that thefe 
 
 perties. 
 
 Sophifticati- 
 
 011s. 
 
 •Chemical 
 
 chara&ers. 
 
 Solution. 
 
 are effential to the Ambergris, but as they are marks of its genuinenefs. The beft 
 Ambergris is light, like wax to the touch, crumbly, yet fomewhat tenacious, 
 fo as to flick to the mortar or peflle ; it has an agreeable fmeil, but no re- 
 markable tafle: It eafily melts in the fire, takes flame from a candle, and 
 burns away without intermi-ffion. 
 
 Ambergris is counterfeited or adulterated with Wax, Refin, Storax, Benzoine, 
 Amber, Labdanum, Mufk, Civet, Aloes-wood, old decayed Afh-wood, Rice 
 Meal, Tree Mofs, and other like fubftances. Thefe abufes are eafily detected. 
 The counterfeit forts are commonly uniform throughout, both in colour and 
 texture, like a pafle or mafs of pills, which the genuine Ambergris never is. 
 The former commonly {'often fooner in the warm hand, and never have the 
 true Ambergris fmeil, no art being able to perfectly imitate this. The fmeil 
 is mofl readily diftinguifhed in melting the Ambergris on burning coals, or 
 in a Silver fpoon over a candle or in the flame : It fmells at lafi: like burning 
 Amber, but not fo ftrong. The true Ambergris bubbles up in melting, and 
 after fufion appears brown. Some judge of its genuinenefs, from the appear- 
 ance of a matter like melted Refin upon piercing the mafs with a red-hot 
 needle, or other fiender inflrument. Menflrua likewife afford ready methods 
 of diftinguifhing the genuine from the fophifticated. 
 
 Ambergris melts in boiling water like a Refin, and communicates to the 
 liquor a little of its fmeil, which arifes along with the water in diflillation. It 
 dilfolves in Linfeed oil if the Ambergris be previoufly melted, and the oil freed 
 from water. It has been hitherto looked upon as exceeding difficultly, and 
 not at all totally foluble in Spirit of Wine ; the Spirit being fuppofed to exrradl 
 
 a fmall part, as it does from Amber. 
 
 I have found however, that this 
 Menftruum 
 
Bituminous Substances, 241 
 
 Menffruum maybe made to diffolve Ambergris both readily and totally. If Ambergris. 
 Ambergris, broke in pieces, be put into twelve times its weight of a good tar- 
 tarized Spirit of Wine, or of a plain highly rectified fpirit * the fpirit will ex- 
 tract little till it begins to boil, but will then quickly diffolve the whole of the 
 Ambergris except its impurities. If the fpirit is impregnated with any effen- 
 tial oil, whether by drawing it over from oily vegetables, or by adding the oil 
 itfelf, it will diffolve Ambergris more readily, and in a lefs degree of heat 
 than would otherwife be neceffary : I have tried likewife the rectified Oil of 
 Amber, and found that this, as well as the vegetable diltilled oils, promoted 
 the adtion of the fpirit j but that expreffed oils, recommended by Schroder, had 
 no effect. The tindture made in tartarized fpirit is of a deep reddifh colour , 
 that made in pure fpirit has fcarcely any colour. The refiduum appears of a 
 large volume, though when dried, it proves to be only averyffnall quantity of 
 a fine earthy matter, amounting when the Ambergris is free from vifible im- 
 purities, to a grain or two upon two fcruples. It is probable that Ambergris 
 has often been diffolved, though the palenefs of the folution, and apparent 
 bulk of the refiduum, have induced the operator to think otherwife. In keep- 
 ing the tindlure or folution, if the veffel is loofely ftopt, fo as to fuffer a. 
 part of theMenffruum to exhale, a proportionable quantity of the Ambergris 
 precipitates, in form of a white unftuous fubftance like tallow, foluble again 
 upon adding more fpirit. Lemery looked upon this as wax, and hence endea- 
 voured to prove that Ambergris proceeded from the labour of bees The 
 
 dulcified Spirits of Vitriol, Nitre and Sea fait, and the dulcified or vinous 
 Spirits of Sal ammoniac made both with Quick-lime and with fixed alcaline 
 Salts, digefted with Ambergris, did not diffolve it, and extracted extremely little ■: 
 
 It was obferved that in the digeftion with dulcified Spirit of Vitriol, and with this 
 only, the little it did extradt concreted about the Tides of the glafs into fmall 
 faline cryftals. 
 
 Dr. Grimm gives an analyfis of Ambergris by diftillation in the Ephemerides i^ftiu at j on 
 nature curioforum. An ounce diltilled in a glafs retort, yielded firff an aqueous 
 liquor, then, as he calls it, a fpiritual liquor, afterwards a yellow oil with a 
 fmall quantity of volatile Salt, a pitch-like matter remaining in the retort. He 
 obferves, that the liquor, the oil, the fait, and the refiduum, were all fimilar 
 to thofe obtained from Amber, except that the oil was in fmell more agree- 
 able 1 repeated this experiment with a dram of Ambergris, and obtained 
 
 the fame produfts, except as to the pitchy refiduum, fcarcely one grain of duff 
 or earthy matter being here left, probably from the fire having been longer 
 continued or raifed higher than in Grimm’s experiment. The quantity of oil 
 was two fcruples and a half, of phlegm five grains, and of Salt two grains. 
 
 Both the oil and the fait agreed with thofe of Amber. 
 
 The analyfis of Ambergris confirmed me in the opinion that this concrete, 
 whofe origin was formerly fo much difputed, is truly a Bitumen of the Amber 
 kind ; and accordingly I communicated my obfervations to the Royal Society in 
 London, in the year 1729. The fadts were called in queftion by fome of the 
 Englifh chemifts •, and about three years after, Sir Hans Sloane fent me an 
 account of the experiments made by Mr. Brown and Mr. Godfrey. The for- 
 mer diftilled Ambergris with tobacco-pipe clay, and obtained, firff a clear 
 
 I i phlegm, 
 
242 Bituminous Substances. 
 
 phlegm, next a fpirit in colour refembling beer, afterwards a darker coloured 
 oil, and at laft a black balfam : The oil and ballam were nearly the fame with 
 thole of Amber, but no volatile Salt was obtained. Mr. Godfrey made three 
 diftillations of Ambergris, one by itfelf, another with fand, and the third with 
 powdered glafs. On rectifying the liquors diftilled with fand, he had more 
 than half the weight of the Ambergris, of a limpid, balfamic, and bituminous 
 oil, with a phlegm which tailed fourifh, but lefs fo than Vinegar. 
 
 Thefe experiments, inllead of being as was fuppofed, contrary to mine, 
 are entirely agreeable to them, and manifell a llrong refemblance betwixt Am- 
 bergris and Amber in regard to their conftituent parts. The difference in the 
 feveral experiments is this: I obtained from fome pieces of Ambergris a fmall 
 portion of a volatile acid Salt ; the piece examined by Mr. Brown yielded no 
 concrete Salt •, Mr. Godfrey’s yielded no Salt, but an acidulous liquor, which 
 was a folution ot the Salt in phlegm. 
 
 pfes„- Ambergris is uled principally as a perfume, in balfams, fnuffs, dentifrices, 
 
 hairpowders, wafhballs, &c. It was formerly held in fome elleem as a medi- 
 cine, and faid to polfefs nervine, analeptic, aphrodifiac, cephalic and other 
 virtues, but is at prefent little regarded. A tindlure of it is fometimes prepared 
 with Spirit of Rofes: This Spirit has no advantage as a menftruum for the 
 Ambergris above fimple Spirit of Wine, though it may in fome cafes be an 
 ufeful addition in point of fmeli, folutions of Ambergris by itfelf having very 
 little fmeli (z). 
 
 JEWS PITCH. 
 
 Jews Pitch. Y EW S PITCH, Afphaltum , Bitumen Judaicum , Bitumen Babylonicum, is 
 
 v — 1 J found in a foft or liquid Hate on the furface of the Dead-fea, and by age 
 
 Where fo«nd. g rQWS dry anc j hard. The fame kind of Bitumen is met with likewile in the 
 
 earth. 
 
 {%) Additional article.'] In the Swediih 
 Tranfadlions for the year 1 743, there is an 
 account of another kind of marine Bitumen, 
 which was found in confiderable quantity in 
 Finland, of a white colour, refembling tal- 
 low, but more brittle ; in fmeli fomewhat 
 like roafted meat. It feels unctuous, makes 
 paper greafy, fwims on water, burns with 
 a fine blue flame and copious fmoke, and 
 leaves a blackifh brown fubftance like Refin, 
 flexible betwixt the teeth, and not foluble 
 by the faliva. Held over the fire it melts, 
 becomes immediately brown, and feparates 
 into a thin part like oil, and a thicker which 
 flicks to the veflel : Both adhere firmly to 
 the veffel when grown cold. Oil of Al- 
 monds does not adi upon it in the cold : By 
 the affiftance of a boiling heat it diftolves 
 greateft part. Strong tartarized Spirit of 
 Wine diffolves it ; but what is remarkable, 
 * Oxford Society. fMr, Labelye. 
 
 the circumftance on which the folution of 
 Ambergris in that menftruum depends, irrt- 
 pedes the folution of this concrete : As foon 
 as the fpirit begins to boil, a part of the 
 Bitumen falls undiffolved to the bottom. 
 The folution has little colour : In evapora- 
 tion the Bitumen is depofited all round the 
 vefi'el, nearly in its original appearance. 
 
 Specific gravities of fundry Bitumens. 
 
 The above white marine Bitumen 0,770 
 
 Ambergris - 0,789 
 
 Tranfparent yellow Amber - 1,085 
 
 Jet — 1,180 
 
 Staffordfhire Pitcoal - - 1,240* 
 
 Newcaftle Coal - 1,270b 
 
 Scotch Coal - 1,3004; 
 
 Afphaltum - 1,400 || 
 
 Water - 1,00.0 
 
 4 Boyle. (j Boyle. 
 
Bituminous Substances. 243 
 
 earth, in other parts of the world, in China, America, and in fome places of Jews Pitch. 
 Europe, as the Carpathian hills, France, Neuchatel, &c. There are feveral 
 kinds of Jews Pitch in the fhops, but none of them are the genuine fort, and L 
 have little other title to their name, than their being artificially compounded by; 
 
 Jews. They are all firm, folid, and of a blackiih colour, but different in' 
 degree of colour. I examined three forts, the blackilh- brown native Bitumen,’ 
 the be ft officinal fort, of a blacker colour and fomewhat bright, and an infe- 
 rior one, black and gloffj| like common Pitch. ' 
 
 The native Bitumen has no fmell. It is not adted upon by water, nor highly Experiments 
 redtified Spirit of Wine, nor oil Olive, nor the effential oils of Anileed or Tur-on the true 
 pentine. In the fire it grew red-hot, like Turf or a piece of red-hot Iron, Afphaltum, 
 and when cold fell into powder. Held over the fire in a proper veflfel, it d'd 
 not melt, but crumbled as before, and emitted a vapour which took flame on 
 the approach of a piece of lighted paper. Four ounces diftilled in a glafs re- 
 tort, yielded only three drams of an empyreumatic oil, with a little phlegm : 
 
 The oil greatly refembled the native Petrolea, but had fomewhat more of the 
 empyreumatic taint. The Caput mortuum weighed three ounces and a half : 
 
 Two ounces of this were reduced by calcination to one ounce and fix drams i 
 which yielded on elixation with water, leven grains of an alcaline fubftance but 
 not a pure alcaline Salt. It was obfervable in the diftillation, that the bitu- 
 minous or oily matter, in feparating from the earthy parts, vifibly melted, 
 and then arole in invifible vapours, whereas in open veflels, there was no ap- 
 pearance of fufion, the oil immediately exhaling in the air. 
 
 The beft officinal Afphaltum has a difagreeable fmell, like that of Garlic or osl t j, e beft of- 
 Afa fetida. A fmall portion of it is taken up by redtified Spirit of Wine, above ficinal Af- 
 twofcruples of fpiritous extradt being obtained from two ounces. Water dif- phaltum. 
 folves nothing, but elevates a part of its Garlic flavour in diftillation. It dif- 
 folves both in oil Olive, and in the diftilled oils of Anifeed and Turpentine, 
 and unites in the fire with Pitch and Wax. Diftilled Vinegar and Spirit of 
 Salt have no adtion on it, the Afphaltum fwimming untouched on the furface. 
 
 It gives ayellowifh tinge to Spirit of Nitre, and partly fwims on the furface, 
 and partly falls to the bottom. It gives a deeper tindture to Spirit of Vitriol, 
 and totally fwims. It finks in cauftic alcaline Lixivia, and tinges them yel- 
 lowifh, but floats on Ample alcalies, and to thefe alfo communicates a tinc- 
 ture. Vinous Spirit of Sal ammoniac feems to extradf the deepeft colour ; the 
 watery fpirit gains but a very flight one : In the former, the Afphaltum totally 
 finks, in the latter a part of it fwims. Four ounces yielded in diftillation, two 
 ounces five drams and one fcruple of oil, and only about two fcruples of 
 phlegm, above an ounce of Caput mortuum remaining. The oil was thickifh, 
 of a dark brown colour, and had a ftrong fmell and tafte like thofe of Garlic : 
 
 It arifes firft in white, then in yellow, and at laft in darker coloured vapours : 
 
 As foon as the yellow fumes appeared, the matter in the retort begun to melt. 
 
 Nothing ialine appeared in the diftillation or could be extradted by hot water 
 from the oil, or from the calcined Caput mortuum. 
 
 The inferior Pitch- like Afphaltum melted as eafily as common Pitch. From on an j n{ - ei .; or 
 four ounces I obtained almoft full three ounces of dark brown oil, and a fmall fort, 
 portion, about half a fcruple, of phlegm, the refiduum making up the fourth 
 
 I i 2 ounce: 
 
244 
 
 Bituminous Substances. 
 
 Jews Pitch, ounce: Scarce any thing-faline could be difcoveredin the refiduum by calcina- 
 tion and elixation with water. Two ounces being digefted in re&ified Spirit 
 of Wine, the filtered liquor left on diftillation fifteen grains of extract : The 
 fpirit drawn over fmelt of Garlic or Afa fetida. Whilft another parcel was di- 
 gefting in reftified Spirit, no vifible folution being made, I dropt in an effential 
 oil ; it was oil of Savin that came firft to hand : The fpirit now begun to a£t, 
 and by the time an hundred drops had been added, appeared confiderably 
 tinged : The quantity of Afphaltum was a fcruple, and of fpirit two drams. 
 The folution was here effected by virtue of the oil, and not of the fpirit : For 
 upon digefcing another fcruple of the powder with a dram of the oil of Savin, 
 nearly all the Afphaltum was foon diffolved : On adding rectified Spirit of 
 Wine, it was thrown down again, and the fpirit fcarcely appeared tinged. 
 
 From thefe experiments it is evident, that the officinal Afphalta are very 
 different from the genuine natural bitumen ; and as they are a medly of we 
 know not what ingredients, their medicinal ufe begins to be defervedly laid 
 afide, notwithstanding the difcutient, refolvent, pedtoral and other virtues 
 attributed to this bitumen by the ancients. The Afphalta of other countries 
 appear to be as little genuine as ours : In Du Hamel’s hiftory of the French 
 Academy of Sciences, we find that two pounds of the French Afphaltum 
 yielded fourteen ounces of oil ; from whence we may prefume, that this was 
 one of the oily artificial compofitions, the native Afphaltum not affording 
 one fourth fo much. 
 
 This bitumen was formerly ufed in embalming the bodies of the dead. At 
 prefent the thick and folid bitumens are employed in Egypt, Arabia, and 
 Perfia, as Pitch for ffiips i and the fluid ones, for burning in lamps, and for 
 varniffies. Some writers relate, that the walls of Babylon, and the temple 
 of Jerufalem, were cemented with Bitumen inftead of mortar. Thus much is 
 certain, that a true native Bitumen, that for inftance which is found in the 
 difirid: of Neuchatel, proves an excellent cement for walls, pavements and 
 other purpofes, uncommonly firm, very durable in the air, and not penetra- 
 ble by water. The watch and clock- makers ufe a compofition of Afphaltum, 
 fine Lamp-black, and oil of Spike or Turpentine, for drawing the black 
 figures on dial-plates : This compofition is prepared chiefly by certain perfons 
 at Augfburg and Nurenberg. 
 
 Ufe?, 
 
 IV. P I T - G O A 
 
 P I T-C O A L 
 V — _v 
 
 Natural hi- 
 flory. 
 
 p I T C O A L, Garbo fojfilis , Anthrax , Lithanthrax , is a bituminous foffil, 
 found in feveral parts of the world, moll plentifully in England and Scot- 
 land, from whence it is exported, in large quantities, into other countries, for 
 the common purpofes of fuel. The moll confiderable Coal-pits are in the 
 neighbourhood of Newcaftle, and the coals dug here are likewife accounted 
 the belt, though forne of the Scotch forts render their fuperiority difputable. 
 Some other parts of England, as Somerfetfhire, Staffordlhire, &c. af- 
 ford alfo plenty of Coals. Next to the Englifh and Scotch, the French 
 are held to be the beft, particularly thofe of St. Etienne foreft, and Au- 
 vergne: There are Coals likewife in other parts of France, as Burgundy, 
 
 Nivernois, 
 
Bituminous Substances. 2 45 
 
 Nivernois, &c. thofe of St. Dizier are the word. In Kircher, the German P i t-C o a l, 
 ephemerides, the Breflau collections, &c. we find accounts of Pit-coal dug in 
 the ifland Elva, in Sicily, and in different places of Italy ; between Neufol 
 and Chremnitz ; in the dutchy of Wurtemberg ; at Altdorff near Nuremberg, 
 and at Kalterfnortheim on the river Fulda in Eifenach ; in the ifland Born- 
 holm, in Bohemia, Heflia, Saxony, &c. It is faid that there are externa! 
 marks, by which the traCts of land that abound with Pit-coal may be didin- 
 guifhed : That the ground itfelf is either manifedly bituminous, or feldom has 
 any Dew : That the Snow melts fooner than in other places : That the trees 
 are fmall, and that their roots contain a bituminous juice : And that the air, 
 in hot fummer weather, is highly fulphureous. 
 
 There are many different forts of Pit-coal; light and heavy, fpongy and Di5erentforts». 
 com pad ; brittle and firm earthy and ftony; of a more or lefs difagreeable 
 fmell in burning : The vapour of all the forts is generally difagreeable to thofe 
 who are unaccuilomed to it. The French divide Pit-coal into two kinds, 
 which they didinguifh by different names : The light and brittle are. called 
 Gharbons de terre , Earth-coals ; the ponderous and comp aft, Charbons de pi err 
 Stone-coals. There is a hard, light fort, very compaCt, fmooth and equal ; Jet., 
 not ftaining the fingers like thofe commonly ufed for fuel ; capable of being 
 polifhed, filed, cut, and turned in a lathe •, ufually made into fnuff-boxes, 
 bracelets, and other elegant toys ; called Gagates and Succinum nigrum , jet or 
 black Amber. The fined of this kind is met with in England, particularly in 
 Staffordfhire and in Cornwall. This appears to be a fpecies of Bitumen di- 
 dinCt from the common Pit-coal, and to be rather a bituminous Wood than 
 an original Bitumen : It looks like fine black ebony. In the fire, it fooner 
 catches flame than the common Coals, and burns rather with a bituminous 
 than fulphureous fmell. Some pieces, in which the woody matter prevails, 
 fmoke but do not flame : Thefe are not to be looked upon as a Bitumen of 
 this fpecies. See Boyle’s treatife on the origin of gems. 
 
 The belt Coals are thofe which fooned take fire, burn longed, and give jviarks of 
 the greated heat. The characters laid down in the GEconomical lexicon as goodnefs, 
 marks of good Coals, their emitting a black fmoke, yielding a watery moif- 
 ture on being preffed, and not burning without bellows or itrong wind, are 
 marks not of good, but of the bad German Coals. Good Pit-coal yields a 
 thick yellowifh fmoke, gives out nothing upon expreflion, unlefs moiftened, 
 and burns without any itrong impulfe of air. 
 
 The bed fort of the Halle Pit-coal, digeded and boiled in Water and in Experiments, 
 rectified Spirit of Wine, gave out nothing confiderable to either. Forty-eight 
 ounces, didilled in a glafs retort, with a fire gradually increafed, yielded two 
 ounces feven drarns of phlegm ; two ounces and one dram of a thin fluid oil ; 
 and one ounce of a thick, tenacious, ponderous, pitchy oil, which duck in 
 the neck of the retort The refiduum weighed forty-one ounces feven drams. 
 
 Nothing of the acid Salt like that of Amber, which Hoffmann obtained from 
 Pit-coal, was here difcovered : The didilled liquors gave marks rather of an 
 urinous and ammoniacal matter, changing Syrup of Violets greenifh, and 
 emiting an urinous odour on the admixture of fixed alcaline Salts or. 
 quicklime. The Caput mortuum , calcined and elixated with Water, yielded a 
 
 fmall' 
 
24S 
 
 Bituminous Substances. 
 
 I i t-Coai. fmall portion of faline matter, not alcaline but rather aluminous, a folution 
 of it being rendered turbid by fixt alcaline Salts, and depofiting an earthy pre- 
 cipitate. The Oil arofe in yellow fumes, and fmelied confiderably fulphure- 
 ous; it fomewhat ftained polifhed Silver, but the ftains were eafily rubbed off: 
 That which diftilled at fir ft was light, and fwum on Water; the fucceeding 
 
 parcels proved more and more grofs and ponderous, and 
 Coals, during the difiillation, looked like melted pitch- 
 
 Ufes and in- 
 
 ■convenien- 
 
 cics. 
 
 at laft funk. The 
 ——The coarfe ftony 
 Pit-coal of Halle yielded no oil : From two ounces were obtained only a dram 
 of liquor, of a ftrong fulphureous fmell ; and about half a dram of a yellow 
 fublimate, greatly refembling common Sulphur : The refiduum weighed one 
 ounce, fix drams and a half. 
 
 Pit-coal, an excellent fuel for common ufes, is for many purpofes unfit. It 
 cannot be employed for the running down of Iron or other ores, which are 
 fmelted in contadt with the fuel ; not, as fome have fuppofed, that the foflil 
 Coal does not give fufficient heat; but from its fulphureous fubflance corrod- 
 ing and fcorifying the metal, or rendering it brittle; whilfi: vegetable Coals 
 fupply only the fimple inflammable principle neceffary for receiving the metal 
 into its metallic form. Thofe which are in any considerable degree fulphure- 
 ous, render Iron brittle even on the blackfmith’s forge. Nor are foflil Coals 
 proper for fufion in crucibles, as they melt and cake about the veffel, and 
 endanger its cracking : The glaflf-makers in England have been greatly dif- 
 treffed by this ill quality of Pit-coal, and the fcarcity of wood ; infomuch as 
 to proffer a reward of ten thoufand pounds to thofe who difcovered a compo- 
 
 fition for pots that fliould beft Hand Pit-coal fires In Brabant, Liege, 
 
 Cologn and other places, the fmall Coals, which would burn away too foon 
 or fall through the grate, are commonly reduced into powder, mixed with 
 loam, and formed into cakes or maffes, which are employed with good ad- 
 vantage for the fame purpofes as large Coals The fmoke of Pit- coal has 
 
 been generally fuppofed prejudicial to health : Hoffmann appears to be the 
 
 firft who has maintained the contrary, and I am entirely fatisfied of thejuft- 
 nefs of his opinion. I never obferved the leaff prejudice from them during my 
 long refidence in London ; and it may be obferved, that even when we are 
 immediately expofed to the fmoke, it does not affedt the eyes like the fmoke 
 of wood. 
 
 SECT. 
 
[ 2+7 ] 
 
 ; ,j 
 
 SECT. V. 
 
 WATER. 
 
 W ATER is an univerfal fluid, diflributed in abundance through all Water, 
 the kingdoms of nature, but referred moll properly to the mineral, * — _»• 
 
 from its being collected in fuch immenfe relervoirs in the earth. ItDiffufedthr® 
 is diffufed through the atmofphere in the warmefl and drielt weather : Alca- ^0^3 of 
 line Salts grow moill in the air in the greatefl droughts : Metallic veflels, ture> 
 cooled by the application of the ice or fnow and made thoroughly dry, collect 
 watery drops on being brought into a warm air, by condenfing the aqueous 
 vapours that imperceptibly floated in it. 
 
 Water is the bafis of all liquids. Not only acid, alcaline, vinous Spirits, The bails of 
 but Oils themlelves, owe to Water their liquid Hate. It is an ingredient in all liquids, 
 the compofition of all animal and vegetable bodies, even of their hardelt and^* 
 mofl folid parts ; as alfo in that of all minerals, unlefs the precious Hones and 
 pure metals be exceptions. Some of the cryflalline Salts in particular, as 
 green Vitriol and Alum ; though folid, hard, and to appearance perfectly dry; 
 are found upon experiment to abound with Water ; and to lofe their folidity 
 and cryflalline form upon feparating their Water, whether by the force of fire, 
 or more gradually by the natural gentle warmth of the atmofphere. W T hen 
 Water is confidered as entering the compofition of bodies, or extracted from 
 them by art, it is commonly called by the chemifls phlegm. 
 
 There is a conflant circulation of Water from one region of nature to an- Conftant clr- 
 other. This fluid is continually exhaling by the fun’s heat, from the furfaceculation of 
 of the ocean, from rivers, fprings and ponds, from the earth, from animals water " 
 and vegetables, into the air ; and being there accumulated, and condenfed, 
 defcends again, in rain, fnow, hail and dew ; affording frefh fupplies to the 
 mineral fources, to the animal and vegetable worlds. By this uninterrupted 
 circulation, the fluid itfelf is preferved from putrefaction ; and all the fublu- 
 nary creation recruited with fucceflions of fweet W ater. 
 
 Water exhales more eafly from fome fubflances than from others ; from Stone? a .Q an .j es 
 Sands, Bolar-earths, Refmous woods, more eafily than from faline, unCtuous, fat bodies in 
 gelatinous, mucilaginous juices, and flimy earths: Hence there are foils, wh cli its exhala- 
 retain moiflure longer than others. It carries off in its exhalation fundry If. b - tion " 
 
 Hances, which of themfelves would not arife : Some bodies, which by them- 
 felves abide fixed and unaltered in the mofl intenfe degrees of fire, vitriolated 
 Tartar for inflance, exhale into the air along with the vapour of boiling 
 Water. The air receives alfo an infinity of effluvia from fires, mineral works 3 
 putrefactions, and other natural or artificial refolutions of bodies. Hence the 
 
 atmo.fr 
 
 5 ; 
 
2 
 
 A 
 
 T 
 
 E 
 
 R,. 
 
 w 
 
 Vv 7 a t e r. atmofpberical Waters, though purer than the fubterraneous, are by no means 
 V — — v — -J perfectly pure or elementary. 
 
 Atmofpheri- The atmofpherical Waters are obferved to be more fertilizing to the earth 
 cal waters, than any others. Collected with due precaution, and preferved from any 
 foreign taint, they do not putrefy; though the Rain-waters caught in towns, 
 in cifterns, in gutters of houfes, foon corrupt. To obtain rain, Snow or Hail- 
 water in their greateft natural purity, they lhould be collected in clean glafs 
 veffels, in an open field, at a diftance from towns or houfes, at a time when 
 the air is pure, not when the Rain or Snow begin, nor till a confiderable 
 quantity has fallen, that the lower air may be firft waffled from fuch hetero- 
 geneous matters as may have floated in it. Dew, collected on clean linen 
 clothes flretched, in clear Weather, at fome diftance above the grafs, ap- 
 pears to be one of the pureft of the natural Waters ; though Boerhaave makes 
 Hail-water the pureft, and next to it that of Snow ; accounting dew to 
 be the moft impure of all, to be a chaos of different exhalations from the 
 earth : Such indeed it may be, when gathered immediately from plants, but 
 not when obtained with the precautions above-mentioned. The dews of 
 May, and the rains of March, are held to be the pureft ; and the rains 
 which fall in fummer to be the leaft pure, the air being in this feafon com- 
 monly loaded with animalcula or their eggs. The rains which accompany thun- 
 der appear to receive no peculiar quality from that circumftance : The ethe- 
 real vivifying fpirit, which fome have fuppofed them impregnated with, is 
 merely imaginary. 
 
 Common wa- The Waters found in the earth or upon its furface are divided into fweet 
 ters. and mineral ; the firft including thofe which are perfectly infipid and anfwer 
 
 for the common purpofes of life ; the other, thofe which have a manifeft tafte, 
 and are impregnated with faline or other mineral matters. Of the fweet 
 Spring-water. Waters, that of fprings, when truly fweet, is the pureft. The beft Spring- 
 water is that which runs through open, hilly, rocky, Tandy, gravelly coun- 
 tries : The Waters which iffue from black mould, in low and fhady grounds, 
 is greatly inferior. Spring-water is divided into four kinds : Aqua fcaturiens 
 or viva , fuch as bubbles up naturally at the furface of the earth : Aqua fontana, 
 fuch as is lodged deeper, and which, when difcovered by digging, is enclofed 
 and raifed by a pump: Aqua putealis , Spring-water uninclofed, or in open 
 wells or cifterns : Aqua / aliens , Spring-water conveyed by pipes. All thefe 
 Waters are at bottom the fame, and differ only in being more or lefs fubjeCT 
 to accidental impurities after their dilcharge from the fpring. Not to men- 
 tion the duft, animals, (Ac. which open wells are liable to receive; even the 
 Waters conveyed by pipes may corrode fome of the matter of the pipe or its 
 cement, and thus contract difagreeable qualities. I have examined the aque- 
 ducts at Rome, thofe between Marly and Verfailles in France, and thofe by 
 which London is fupplied with the New-river Water ; and found them to be 
 in fome places liable to this inconvenience. 
 
 River- waters are generally fuppofed to be purer than thofe of fprings, but 
 iRiver-watei. j cannot a g ree i n this opinion. All Rivers proceed originally from fprings, 
 and furely they are more liable to gain than to lofe impurities in their courfe. 
 What an immenfity of filch do rivers receive from populous towns and manu- 
 factures ? 
 
T 
 
 E 
 
 R. 
 
 W A 
 
 249 
 
 failures ? and even in places remote from towns what variety of light vege-W a t e r. 
 
 table and earthy matters is blown into them by every wind ? (a) The fmailer, ' — . — * 
 
 navigable, unfrequented Rivers, in ftony or rocky countries, between hills, 
 full of ftones, of a rapid courfe, are generally the cleareft and pureft. 
 
 The ftagnant Waters of lakes, ponds, marfties, pits, ditches, are the molt Pond-waters. 
 impure of all: As they are open, they are fubjed to extraneous impurities , 
 and as they are ftagnant, they are difpoled to putrify. The lmaller the body 
 of Water, the more it is liable to putrefaction. 
 
 Mineral Waters may be divided into faline, bituminous, and noxious. TheMineral-wa« 
 faline Waters are of three kinds, thofe impregnated with common Salt, the ters - 
 Waters called medicinal, and thofe whofe impregnation is too inconfiderable 
 to recommend them to the notice of the phyfician. There are two natural 
 folutions of common Salt ; Sea-water, and that of faline fprings or brine-pits. 
 
 The laft are commonly not only richer in Sait, but more pure folutions of it 
 than the firfb. 
 
 Sea-water is naturally dear and colourlefs as common Water ; though it Sea- water, 
 fometimes exhibits greenifh, yellowifli, bluifh, reddifh, brownifh, blackifh, 
 
 and 
 
 (a) Spring and River-waters.'] River-wa- 
 ters, though they fhould feem, from the 
 confiderations above-mentioned, to be far 
 lefs pure than thofe of fprings, are never- 
 thelefs found, from daily experience, to be 
 the pureft of the two, or at leaft to be the 
 beft adapted to the common purpofes of 
 life. Spring-waters are very often bard, 
 do not boil peas tender, or form a fmooth 
 lather with fope, or anfwer for dying, 
 bleaching, wafhing, &c. whilft thofe of 
 rivers are in general foft , and fit for all 
 thefe ufes, almoft equally with Rain- 
 water. 
 
 The hardnefs of Spring-waters has been 
 generally aferibed to their being impreg- 
 nated with Sea-falt. Dr. Home has {hewn, 
 in his ingenious eflay on bleaching, that 
 neither pure Sea-falt, nor any of the per- 
 fectly neutral Salts, compofed of an acid 
 and an alcali, give any hardnefs to Water : 
 That the common forts of Sea-falt make 
 Water hard, by virtue only of the hetero- 
 geneous Salt which they retain from the 
 bittern (fee page 21 r.) That all acids, and 
 Salts compofed of an acid and an earthy or 
 metallic fubftance, have this effed: : And that 
 the offending ingredient in hard Spring- waters 
 is a combination of an acid and earth. Sope 
 is a compofition of Oil and alcaline Salt : 
 On mixing this compound with fuch a 
 Water, its alcali is abforbed by the acid 
 of the Water, upon which its oil, de- 
 
 prived of the fubftance that made it mifei- 
 ble with aqueous liquors, feparates and 
 curdles on the furface : At the fame time, 
 the earth of the Water, now forfaken by 
 the acid that held it difl'olved, fettles to the 
 bottom. It follows from this theory, that 
 alcaline Salts in their pure ftate will difeo- 
 ver hardnefs in Waters more effectually 
 than fope, by turning the Water milky or 
 cloudy, and precipitating its earth. 
 
 It follows alfo, that by thus precipitating 
 the earth, and neutralizing the acid, they 
 will foften the Water; and on trial, they 
 are a&ually found to produce this definable 
 effeCt : If a folution of any fixed alcaline 
 Salt is dropt in by degrees, fo long as any 
 cloudinefs enfues, and the liquor differed 
 to fettle till it becomes clear ; how hard 
 foever the Water was before, it is now 
 found to be foft, and fit for all the pur- 
 pofes of life .... The fame gentleman ob- 
 ferves, that hard Waters are indifpofed to 
 corrupt, and even preferve putrefcible fub- 
 ftances for a confiderable time : Whence 
 they fhould feem the beft fitted for fea, 
 efpecrally as they may be at all times fo 
 eafily foftened. It has been fuppofed, that 
 thefe Waters become purer by boiling: 
 But though, in proportion to the evapora- 
 tion of the fluid, a part of the earth fepa- 
 rates and incruftates on the Tides of the 
 vefi'el, the remaining liquor is found to be 
 harder than at firft. 
 
 K k 
 
2<0 W A T E R. 
 
 Wate R.and other colour?, front accidental admixtures, or agitations of the Water by 
 
 * — — J ftorms, or different reflexions of the fun’s rays. The fuperficial parts of the 
 
 Water are lighter, lefs faline, and more coloured than the lower : While 
 twelve ounces of the fuperficial Water yielded three drams of Salt, the lame 
 quantity, taken up from a confiderable depth, has afforded fifteen grains more. 
 The tafte of Sea-water is not only faline, from the common Salt, but mani- 
 feftly bitter. 
 
 Bitternefs of Count Marfigli endeavours to prove, that Sea-water contains a bituminous 
 Sea-water matter, from which its bitternefs proceeds. He obferves that pure common 
 ^PP^^^V'Salt being diffoived in Water in the proportion above-mentioned, namely 
 mfn. C ° three drams to twelve ounces, with the addition of a fcruple of Spirit of Pit- 
 coal, the liquor was found to have the bitter as well as the faline tafle of 
 Sea-water: That a part of the bituminous matter arifes with the Water in dis- 
 tillation, and incruftates on the fides of the glafs in which the diftilled Water 
 is long kept: That a pound of Sea-water diffoived two drama and fifteen, 
 grains of Salt befides what it naturally contained ; and that common Water 
 diffoived more than the Sea- water could be impregnated with. 
 
 Owingwholly From thefe and other experiments it is probable, that Sea-water contains a 
 to bitter Salt. portion of a bituminous fubftance, but not that the bitternefs depends on this 
 ingredient. There are fundry neutral Salts, as vitriolated Tartar, the Sal 
 mirahile of Glauber, the Salts of the purging mineral Waters, which have a 
 very confiderable bitternefs, though they contain nothing bituminous ; and 
 does not a Salt of this kind actually exifl in Sea-water ? (See page 211.) 
 
 It may be proper to obferve, that Sea-water contains often a nitrous mat- 
 ter ; the acid fpirit diftilled from Sea-falt proving a menftruum for Gold, 
 which the marine acid by itfelf never does, and which nothing but the nitrous 
 will enable it to do. Though this however is frequently the cafe, it is not 
 always : I have examined marine Salt, whole acid had no action on Gold. 
 Methods of Different methods have been contrived for fweetening Sea- water, or freeing 
 fweetening jt from the Salt, fo as to render it fit for drinking and for the common ufes 
 Sea-water. Q f fjf e< Some have endeavoured to feparate the Salt in the way of precipita- 
 tion *, but all the known fubftances, that are capable of throwing down any 
 of the Salt, are in part retained themfelves by the Water, fo as to communi- 
 cate to it difagreeable or dangerous qualities. Others have propcied filtration 
 through porous ftones, fands, and infipid earths : It appears from experience, 
 that Water, in pafting through a confiderable thicknefs of thefe kinds of fub- 
 ftances, will leave great part of its Salt behind, and by repetitions of the filtra- 
 tion, nearly the whole : But the quantity of ftony or earthy matter requifite 
 for this purpofe is much too large, and the procels itlelf too tedious, to have 
 place on board a fhip, where fuch expedients are principally wanted. Beefier 
 mentions a certain pump, contrived by one Walker in England, by means of 
 which frefh Water might at once be pumped up from the Sea: This inftru- 
 ment was not only found too expenfive, but wanted durability, and could not 
 be worked on board a fhip. The belt method is diftillation : The only ob- 
 jections to this are, that diftilled Sea-water does not quench thirft: like com- 
 mon fweet water, and that the procefs is too expenfive and incommodious to 
 be praCtifed at fea. The firft may be eafiiy remedied by certain additions, 
 
 that 
 
Water. 251 
 
 that fa all abforb the loofe acid in the Water, and prevent its a riling : With W a ter* 
 regard to the other, diddling veffels have been contrived, in which the pro- 
 ceis may be continued without intermiflion, in all kinds of weather, not- 
 withftanding the motions of the fhip, with little fuel, and at little ex- 
 pence (b). I faw, in the French academy, a drawing of a curious machine 
 of this kind invented by M. Gautier, of which there is fome account in the 
 Breflau collections for the years 1717 and 1718. It were greatly to be wilhed 
 that this procefs could be introduced into general practice, fo as to relieve 
 the diftrefles to which failors are fo often expofed, from their Water either 
 failing, or putrefying and breeding worms. Boerhaave informs us, that the Prefervation 
 Dutch Eaft India fliips ufe a faline mixture for preferving their Water fweet, ofVVat< i rfrom 
 compofed of twelve parts of Aqua fortis or Spirit of Nitre, ten parts of clean C0riU P tl0n * 
 Rhenilb Tartar, and two parts of purified Saltpetre: Thefe ingredients are 
 put into a glafs body, and digeited in the heat of a Water-bath till the Salts 
 are dilfolved, after which the liquor is drained and let by to fettle. The 
 Water, to be taken in is boiled, an ounce of this faline liquor added to every 
 eighty pounds, the boiling continued a little longer, and the Water, when 
 grown cold, filled into calks. 
 
 The fecond fort of Waters impregnated with Sea-falt is the Brine-water or Brine-fprings, 
 that of faline fprings : From this, the purelt common Salt is ufually extradited. 
 
 The quantity of Salt is different in different fprings ; fome holding no lefs than 
 three ounces and three drams upon a pound, and fome few dill more ; whild 
 others contain lefs than Sea-water does, fome fcarce two drams on a pound. 
 
 Thefe Waters are for the mod part a pure brine of common Salt, though 
 fome of them have alfo an aluminous impregnation (r), 
 
 [b) Sweetening of Sea-water.'] This pro- 
 cefs has of late received notable improve- 
 ments from the happy induftry of Dr.Hales. 
 He finds, that the addition of a fmall pro- 
 portion of chalk ferves to prevent any acid 
 from arifing, and thus renders the diftilled 
 liquor perfectly fweet : And that by driving 
 a ftream of air through the Water in the 
 dill, the quantity drawn off proves at lead 
 double to what would arife in an equal 
 time without that aflidance. By this me- 
 thod, he obferves, a dill which holds 
 twenty gallons will yield, in twenty hours, 
 two hundred and forty gallons of frefh 
 Water, with little more than two bufhels 
 of coals. A fmall dill, of five gallons, pro- 
 duces fixty-four gallons in twenty hours. 
 The dill may be occafionally fupplied with 
 Sea-water by a cock in the head, without 
 lofs of time in unluting it ; and that all 
 poffible advantage may be gained, the Wa- 
 ter warmed in the worm tub may be em- 
 ployed for this purpofe. 
 
 It is faid, that the diff illation is dill fur- 
 
 K 
 
 ther expedited, by dividing the head of the 
 dill into a number of partitions, by parallel 
 plates. There is doubtlefs confiderable 
 room for improvement in the ftrudture of 
 dills ; but the particular advantage of this 
 condrudtion I do not apprehend. The 
 largenefs of the furface expofed to the air, 
 or to any other medium lefs hot than the 
 included vapour, will undoubtedly promote 
 its condenfation ; but plates within the dill- 
 head mud foon become equally heated with 
 the vapour itfelf : Perhaps, widening the 
 paffage of the vapour would anfwer better : 
 It is certain that the evaporation of liquids, 
 by an equal heat, is in proportion to the 
 furface of the liquor itfelf, and to the free- 
 dom of the vapours pairing off ; and that in 
 the common dill, the vapour is fo much 
 obdrufted, as when the heat is raifed too 
 high, to blow off the head. 
 
 (c) Brine-fprings • Aluminous impregna- 
 
 tion .] It may be doubted whether any of 
 thefe Springs contain a true Alum. Many' 
 k2 of 
 
A 
 
 T 
 
 E 
 
 R, 
 
 252 w 
 
 Wate r. The Medicinal Waters to which alone cuftom has erroneoufly appropriated 
 A — Tv — — ’ the name of Mineral, are impregnated either with vitriolic acid, with the 
 Medicinal- a ] C aline bafts of Sea-falt, with a terrugineous earth dilfolved by the vitriolic 
 acid, or a certain alcaline earth combined with the fame acid into a bitter 
 purging Salt fimilar to the Sal mirabile. Thefe Waters are commonly divided 
 into Acidula and Thermae •, the fir ft comprehending, not really acid waters as the 
 name imports, but all thole which are cold ; the latter, the hot ones, fome of 
 which are of a quite fcalcling heat. The hot Waters commonly contain more 
 of a grofs earthy matter, imperfectly diffolved, than the cold ; as appears from 
 the hard ftony fubitance, ufually of a yellowifh or reddifh colour, with which 
 the channels of the former are from time to time plentifully incrullated. The 
 methods of examining the contents of particular mineral Waters may be feen 
 in Hoffmann’s writings De acidulis £? thermis , Seip’s treatile of Pyrmont 
 Water, fome papers in the Trench memoirs, &c. The principal trials are, 
 
 1. Evaporation ; by which we not only difcover the quantity of folid matter 
 contained in the Water •, but at the fame time, as we here obtain that matter 
 by itfelf, are enabled to determine what it is : By elixating it with pure Water, 
 we obtain the faline and the indiffoluble parts feparate from one another. 
 
 2. Diftillarion ; by which we are enabled to difcover whether the Water con- 
 
 tains any volatile matter, faline or bituminous. 3. The admixture of certain 
 liquors ; as Syrup of Violets, infufion of galls, folutions of Lead and Silver. 
 Thefe and other liquors exhibit different phenomena according to the fub- 
 ftances which the Water is impregnated with : Thus Syrup of Violets is 
 changed red by acids, and green by alcalies ; infufion of galls ffrikes a black 
 colour with ferrugineous folutions, and with thefe only; folutions of Lead and 
 Silver, dropt into liquors participating of Sea-falt or vitriolic acid, render 
 them cloudy or turbid, and depofite their metal combined with thofe faline 
 bodies [d) Moil of the Medicinal-waters undergo an alteration in their 
 
 com po- 
 
 of them participate of the bitter purging 
 Salt, which has not unfrequently been 
 miftaken for Alum, and which in fome re- 
 fpe£ts greatly refembles it ; both Salts bub- 
 ling up in the fire, and turning into a light 
 fpongy unfufible calx ; and both being 
 compofed of the vitriolic acid combined 
 with an earth : They differ however in 
 many effential properties, the earth in one 
 being of a diftindt kind from that of the 
 other. 
 
 (cl) Examination of Mineral-waters •] The 
 art of inveftigating the contents of Mineral- 
 waters has been encumbered with a multi- 
 plicity of experiments more oftentatious 
 than ufeful. The phaenomena refulting 
 from the admixture of other bodies with 
 the Water are for the mod part fallacious ; 
 Waters very diffimilar in quality exhibiting, 
 
 on thefe kinds of trials, fimilar appearances. 
 The principal additions made ufe of in this 
 view, and the changes enfuing upon their 
 mixture with different Waters, are as 
 follows. 
 
 Syrup of Violets is changed red by Waters 
 impregnated with a pure acid, or with 
 Alum ; and green by fuch as contain a 
 prevailing alcali, a combination of calca- 
 reous earth with marine acid, and fome 
 other compound Salts both earthy and me- 
 tallic . . Alcalies effervefee with acid Waters, 
 and with fome of thofe which contain Salts 
 compofed of an acid with an earth or me- 
 tal . . Fixed alcaline Salts produce a cloudi- 
 nefs or milkinefs in Waters impregnated 
 with Alum, with the purging bitter Salt, 
 with the Salt called fixed Sal ammoniac, 
 and in general with any combination of 
 acid and earth : They likewife render all 
 
 metallic 
 
T 
 
 E 
 
 w 
 
 A 
 
 R. 
 
 2 53 
 
 compofition, and lofe of their virtue, on being carried to any confrderable di- W atjr* 
 fiance, or long kept ; though taken up and fecured with the greateft precau- ‘ 
 
 tions, 
 
 metallic folutions turbid, and precipitate 
 the metal from thefe, as the earth from the 
 others . . Volatile alcaline Salts or Spirits have 
 the fame general effects as the fixt ; with 
 this particularity, that they ftrike a blue 
 colour with folutions of Copper : Hence 
 volatile alcalies are of good ufe for difco- 
 vering Copper ; and folutions of Copper , for 
 difcovering volatile alcalies . . Sope is curd- 
 led by acid Waters, and by all tbofe which 
 are male turbid by alcalies . . Solution of Sope 
 in vinous fpirits is rendered milky by the 
 fame Waters . . With all thofe Waters alfo, 
 a folution of Sulphur in alcalies or Lime-wa- 
 ter, becomes milky, and emits a ftrong fe- 
 tid fmell . . Acids eftervefce with Waters in 
 which an alcali or earth prevail ; and turn 
 all thofe liquors milky which contain fub- 
 ftances diflblved by alcalies . . A folution of 
 Silver in Aqua fortis produces a milkinefs 
 in all that contain an alcaline Salt, Sea-falt, 
 fixed Sal ammoniac, bitter purging Salt, 
 Alum, Sal mirabile, or other combinations 
 of the marine or vitriolic acids with alcalies 
 or earths . . Solution of Mercury makes all 
 thofe Waters turbid that folution of Silver 
 does . . And folution of Lead , the fame . . . 
 Upon the whole, experiments of this kind 
 may ferve to inform us, that certain Waters 
 participate of fome mineral impregnation, 
 but not to determine what that particular 
 fubftance is. I can recollect but two in- 
 fiances, in which Simple mixture affords 
 any degree of certainty ; the blue colour 
 from Copper and volatile alcali, and the 
 bluifh or purple from Iron and fome aftrin- 
 gents. 
 
 The Simple and obvious method of ana- 
 lyfing Waters, is, to gently diftil a large 
 quantity in clean glafs veflels, and examine 
 the diddled liquor and refiduum feparately. 
 X. The diftilled liquor is fometimes found 
 to turn Syrup of Violets red. We may be 
 fure that this effedt proceeds now from a 
 pure acid, and not from a combination of 
 an acid with any other body. 2. The re- 
 fiduum confifts of a faline part foluble in 
 pure W ater, and an earthy one. By care- 
 ful cryftallization, the Salts may be fepa- 
 rated from one another, and obtained in 
 their proper form ; or they may now be 
 
 difcovered with certainty, by means of ad- 
 ditions, without fuch feparation. 
 
 A prevailing unfaturated alcali is eafily 
 known, by its railing an effervefcence with 
 the marine and with vegetable acids. The 
 fixed matter may eftervefce with the ftron- 
 ger acids, and turn Syrup of Violets green, 
 though it contains no alcali. 
 
 The other Salts are compofed of an al- 
 cali or earth faturated with one or more of 
 the mineral acids . . i. The bafis or fub- 
 ftance combined with the acid, is found, 
 by adding, to the faline folution, a folution 
 of any pure alcaline Salt. If the bafis is 
 an alcali, no change will enfue from the 
 admixture of its like ; but if an earth, it 
 will be precipitated. Spirit of Vitriol, add- 
 ed to the earth, will readily difcover of 
 what kind it is ; this acid difiblving the 
 aluminous earth into an highly altringent 
 liquor, magnefia into a bitter one $ and 
 not at all, or not perfectly diftolving the 
 calcareous. For the greater certainty in 
 regard to this laft, we may diffolve the 
 earth in fome other acid, as Aqua fortis, 
 and then add fome Spirit of Vitriol, which 
 will precipitate the calcareous earth, and 
 leave both the other earths diflblved. 2 . The 
 fpecies of acid may be diftinguilhed by add- 
 ing to the dry compound a little ftrong 
 Spirit or Oil of Vitriol : If the acid is the 
 marine, it will be inftantly expelled in 
 white, and if the nitrous in red fumes ; but' 
 it it is the vitriolic, no change will enftie. 
 The marine acid may alfo- be known, by 
 the matter enabling Aqua fortis to diflolve 
 gold ; the nitrous, by its fulminating, when 
 ignited, on the contact of any inflammable 
 matter ; the vitriolic, by its precipitating 
 any folution of calcareous earth, as of 
 Chalk in Spirit ofi Salt or Aqua fortis. Al- 
 caline Salts alfo precipitate fuch, a folution, 
 but with this difference ; that when the 
 liquor has grown milky, a little frefh Spirit 
 of Salt or Aqua fortis will render it clear 
 again if the effect proceeded from an alcali, 
 but make no change if from the vitriolic 
 acid T The precipitate thrown down by the 
 former is a calcareous earth again, by the 
 latter a felenites. 
 
254 - 
 
 Water. 
 
 Bituminous 
 
 Waters. 
 
 Noxious Wa- 
 ters. 
 
 Properties of 
 pure Water : 
 
 its fpecific 
 gravity ; 
 
 fubtility ; 
 
 in compreffi- 
 bility ; 
 
 porofity ; 
 
 Water. 
 
 tions, and preferred in cool cellars. Where thefe medicines therefore are hat! 
 recourfe to, the patient is always to be advifed to the Spring itfelf : Here, 
 behdes enjoying the Water in its perfect ftate, exercife, change of air, amufe- 
 ments, company, freedom from domeftic cares, will greatly aflift its falutary 
 virtue. 
 
 Bituminous Waters are thofe which have a mineral oil or bitumen either 
 floating diftindt on the furface, or intimately diiiblved in fmaller quantity. 
 There are fundry Waters which abound with bituminous matter, as near Bo- 
 logna, in Neuchatel, in the electorate of Hanover and other places If we 
 feparate from thefe Waters all the bitumen that appears undiffolved, the 
 Water is ftill far from being pure: ft permanently retains a ftrong bituminous 
 fmell and tafte. 
 
 The noxious Waters are of three kinds, i. The petrifying Waters, or fuch 
 as abound with earthy or ftony matter, which incruftates on folid bodies kept 
 in the Water, and often fpontaneoully fcparates, efpecially on the exhalation 
 of a part of the fluid •, whence the ftalaflit#, ftony icicles, dropftones, often 
 met with in caverns of the earth. Some of thefe Waters depofite their con 
 tents in a powdery form ; others in that of a crumbly, and others of a very hard 
 ftony mafs. 2. The vitriolic, cupreous Waters, or thofe impregnated either 
 with a pure vitriol of Copper, or a mixt vitriol of Copper and Iron. 3. The 
 diredlly poifonous Waters, as the arfenical ones found in mines. A Water 
 may be prepared by the chemical art, which though nearly inflpid, fhall be 
 highly poifonous : But as this might be abufed to pernicious purpoles, I for- 
 bear to mention its compofition. 
 
 We have hitherto given a general view of Waters, as naturally blended with 
 other fubftances : We fhall now conftder the principal properties of the purer 
 kinds of fweet Water. 
 
 This fluid is inflpid, inodorous, colourlefs, tranfparent. Its gravity is to that 
 of Gold nearly as one to twenty : Eifenfchmid, in his diflertation De ponderi- 
 lus fsf men[uris veterum , &c. gives an account of the abfolute weight of different 
 forts of Water, in winter and in fummer: He obferves, that a cubic inch of 
 Spring-water, taken in fummer, weighs five drams eleven grains, in winter 
 five drains fourteen grains; the fame volume of River-water, in fummer, five 
 drams ten grains, in winter five drams thirteen grains-, diftilled Water in fum- 
 mer five drams eight grains, in winter five drams eleven grains ; Sea-water in 
 fummer fix drams twelve grains, in winter fix drams eighteen grains. 
 
 Water is an extremely fubtile fluid, capable of pervading not only the mi- 
 nuteft vdfels of animals and vegetables, but by means of prefiure, the folid 
 bodies of metals, even the moft folid and compadt of all metals, Gold itfelf. 
 This appears from an experiment made by the gentlemen of the Florentine 
 academy : A hollow golden ball being filled with Water, the aperture clofely 
 iecured, and the ball ftrongly preffed, the Water oozed out in little drops all 
 over the furface of the metal ; a proof both of the porofity of Gold, and of 
 the fubtility and incompreftibility of Water. That this fluid neverthelefs con- 
 tains pores, or vacuities between its particles, is evident from its diflolving a 
 confiderable quantity of feveral kinds of Salts, without any fenfible increafe of 
 its volume. In 
 
W A T E R. 255 
 
 In a certain degree of cold, this fluid is converted into a folid, hard, tranf- Wa ter. 
 parent, elaftic tnafs, capable of being polifhed like glafs, and, when reduced 
 to the fame figure, producing the fame effedls as the magnifying and burning- congelation ; 
 glaflcs. We may properly, with Boerhaave, look upon ice as the natural ftate 
 of Water ; and its fluidity to proceed from external warmth, not as that au- 
 thor alledges from particles of fire intermixed. If particles of fire confined in 
 bodies were the caufe of fluidity, quickfilver would neceflarily contain more 
 fire than Water does, as being more fluid, and more permanently fo ; and 
 yet Boerhaave himfelf admits that quickfilver is far colder than Water. 
 
 In a fmall degree of heat, it exhales fucceffively in vapours, which caught exhalation , 
 in diddling vefi'els condenfe into water again, unchanged in its quality. The 
 action of air and wind remarkably promote its evaporation, the air imbibing 
 
 and carrying off the watery particles When made to boil, it is found to 
 
 have received the greateft heat which it is fufceptible of : Flow flrongly foever ebullition ; 
 the fire be raifed after this period, tiie water will grow no hotter, provided the 
 veiled is open : Hence we are furniflied with one equal ftandard degree of heat 
 for the graduation of thermometers ( e ) ; and the freezing of water affords an- 
 other. It is obfervable, that if a phial or other vefiel of Water, however thin 
 the glafs, be kept in boiling Water, the Water in the phial will not boil — In heated be- 
 clofe vefiels where the vapour is perfeddy confined, Water may be heated to a>'. ond ebulli- 
 confiderably greater degree than it will receive in open ones, and by this means 110 ”’ 
 its activity on certain bodies, or its power of diffolving them, may be greatly 
 increafed: Hence Papin’s digeflor. But this confinement of the vapour is elaftic va- 
 accompanied with great danger to the byllanders, the vapour of Water whenP ou m 
 flrongly heated, being extremely elaflic, fo as to burft even an Iron bomb- 
 fhell with violent explofion. The extraordinary expanfive power of the fleam 
 of boiling Water is applied to valuable purpoles in feme machines, as particu- 
 larly in the fire engine. 
 
 Water added to burning Wax, Pitch, Refin, Oil, Fat, or other like fubflances, augments 
 increales the flame. Without water there can be no flame, this fluid beingflame; 
 the very bafis of the flame : When Coals, Wood, flfc. are freed from all humi- 
 dity, or reduced to a coal, they flame no longer. Not that Water contains in 
 itielfany thing truly inflammable, or that can ferve as a pabulum of fire ; but 
 from its expanfive vapour proving a vehicle to the inflammable matter of the 
 fuel, and carrying it up in an ignited fiate. Hence it is obferved, that in 
 conflagrations, the throwing on of a little Water increafes the fire. 
 
 Confiderabie degrees of heat and cold are producible in Water, by the bare 
 admixture of certain other bodies. By diffolving in it iome ialine fubflances, made hot and 
 particularly Sal ammoniac and Mercury fublimate, it becomes notably coIder: c °ld by rnix- 
 Qn the other hand, if Oil of Vitriol be hallily poured into cold Water, the mix.- ture ‘ 
 ture becomes inftantly fo hot, that the glafs cannot be held in the hand. 
 
 Water d iff jives all Salts, tho’ not all with equal facility, or in equal quantity. As a men- 
 It diffolves meft eafily the powder Sugars, and fixed aicalies ; next to thefe, fome firuum for 
 of the neutral Salts, as the Sal diureticus, ibluble Tartar,, Sal. mirabile, com- Sal- 
 mon 
 
 (e) Boiling heat.] Later experiments have according to the purity of the Water itfelf^ 
 
 Ihewn, that the heat of boiling Water varies and the gravity of the atmofphere. 
 
256 W A T E R. 
 
 W at e r. in on Salt, Sal ammoniac, &V. More difficultly, Nitre, Alum, Sugar of 
 ■v— ^ milk; molt difficultly of all, Borax, Tartar, vitriolated Tartar, Salt of Sor- 
 rel. Its aftion is in general greatly promoted by heat and by agitation: By 
 means of thefe it may be made to take up a larger quantity of moil kinds of 
 Salts than it is capable of keeping diffolved when thofe caufes are removed: 
 Thus if boiling Water be faturated with as much Salt as it will in that flate dif- 
 folve, a part of the Salt will feparate as the liquor cools. Boerhaave alledges 
 that Water will notdifiblve any Salt without heat: This is a mere play upon 
 
 Cryftalhzati- words, for by Water he means Ice When Water is overloaded with Salts 
 
 on o: Salts; me ans of heat, the part of the Salt which feparates on cooling generally 
 concretes into folid maifes, tranfparent, and of regular figures, and hence 
 called by the c he mills Cryftals , as having fome refemblance in appearance to the 
 Hones of that name. The author above-mentioned makes cold neceffiarv to 
 the cryflallization of Salts : In this he is miftaken ; for many Salts ffioot into 
 more perfect cryftals, if the folution is kept in a gentle warmth that the Water 
 may llowly exhale, than if it is removed into a cold place : The Cryftals of 
 Sugar called SugarCandy, are always prepared in a hot room, and the fame 
 procefs is applicable to fundry other Salts. There are therefore two diftindt 
 principles ol cryflallization : the one, a conftant fucceffive exhalation of the 
 Water by heat ; the other, a diminution by cold, of that power in the Water 
 by which it held the Salt diffolved. 
 
 quantity of Several chemiits have given us experiments of the quantity of particular 
 dilferent Salts Salts foluble in a certain quantity of Water. Thefe experiments agree but ill 
 id Ives'- K ^ one anoI: ^ er : Q ne fays, a pound of W^ater diffolves two ounces of Salt- 
 
 petre, another only fix drams : One, that a pound diffolved an ounce of Ar- 
 canum duplicatum , another as much again : One, that a pound of Water would 
 take up no more than fix drams of green Vitriol, another that it diffolved four 
 ounces and more: One, that Water will diffolve equal its own weight of Ep- 
 fom Salt; and another that it will not diffolve half its weight: And the cafe is 
 the fame in other Salts. I therefore made fundry experiments of this kind my- 
 felf, and found that one ounce of Water diffolved two ounces of white powder 
 Sugar, two ounces of brown powder Sugar, nine drams of white Sugar Candy, 
 nine drams of brown SugarCandy, nine drams of Canary Sugar, one ounce of 
 white Sal diureticus, one ounce of black Sal diureticus, one ounce of Epfom 
 Salt, fix drams ofSedlitz Salt, fix drams of pure fixed alcaline Salt, half an 
 ounce of white Vitriol, half an ounce of Gofiarian Vitriol, half an ounce of 
 Vitriol of Iron, three drams and one fcruple of Sal gem, three drams of com- 
 mon Spring-falt, three drams of Sea-falt, two drams of Sal mirabile, two 
 drams of volatile Salt of Sal ammoniac, two drams of crude Sal ammoniac, 
 two drams of Pot-afh, two drams of Cyprus Vitriol, one dram and ten grains 
 of purified Nitre, one dram of antimoniated Nitre, one dram of Sal prunell, 
 one dram of foluble Tartar, one dram of the Sal embryonatum, one dram of 
 the Salt of the Carlfbade baths, two fcruples and a half of crude Alum, two 
 fcruples of Sal polychreft, two fcruples of the Salt of the Egra waters, half a 
 dram o $ jlrcamim duplicatum ^ half a dram of vitriolated Tartar, one fcruple of 
 .Sugar of Milk, one fcruple of Sugar of Lead, one fcruple of emetic Tartar, 
 
 fifteeen 
 
Water. 257 
 
 fifteen grains of Borax, ten grains of Salt of Sorrel, five grains of whiteWA t e 
 'Tartar, five grains of cryftals of Tartar. v — — 
 
 It is obfervable, that Water, when faturated with one Salt, will full dif- Super-im- 
 folve a confiderable portion of another-, when faturated with this, it will (till ^a^er ^with * 
 take up a third, and thus fuccefiively different forts, till fix, feven or niore Sa j t 7 1 1 
 are taken up by the fame Water. Thus four ounces of Water diffolve 
 only a dram and a few grains of Alum, and will not touch any more of 
 that Salt but the fame Water will diflolve five drams of Salt-petre, after this 
 half an ounce of green Vitriol, then fix drams of common Salt, three drams 
 of foluble Tartar, and five drams of Sugar : It will (till take up an ounce of 
 fixed alcaline Salt, though a precipitation now begins, as always happens upon 
 the commixture of alcalies with aluminous and vitriolic folutions. In like 
 manner four ounces of Water, faturated with half an ounce of Salt-petre, wili 
 diffolve half an ounce of white Vitriol, fix drams of common Salt, fix drams 
 of Sal ammoniac, half an ounce of foluble Tartar, and after all thefe, a whole 
 ounce of Sugar. 
 
 Boerhaave obferves, that there are fome metallic Salts which Water v/ill not Precipitates 
 dilfoive, as the thick fluid called Butter of Antimony. Butter of Antimony fome metallic 
 is a folution of regulus of Antimony in marine acid; which acid does not dit- f° lutI0R2 * 
 folve that femi-metal unlefs the acid is highly concentrated, and, after it has 
 diflolved it, lets it fall again on being diluted with Water. Ifhehadfaid, 
 that fome metallic bodies will not dilfoive in diluted acids, and that when dif- 
 folved in concentrated ones they are precipitated upon diluting the liquor with 
 WHter, as Refins are precipitated from Spirit of Wine ; the obfervation had 
 been juft. - 
 
 Water diflolves vegetable gums and mucilages, as Gum arabic, cherry-tree as a menfthis 
 gum, and extrads the gummy parts of concrete or infpifiated vegetable um for ve S e - 
 juices, as Myrrh, Ammoniaeum ; or of entire vegetable matters, as Marfb- a^maHub 
 mallow roots. Quince-feeds, &c. It likewife readily diffolves and extracts the ft ances ? 
 gelatinous or glutinous parts of animals 5 hence foups, gellies, glues: Bones 
 themfelves are foftened, and all but their earth dififolved by it, in Papin’s di- 
 geftor. Cold and hot Water produce very different effeds on fome animai 
 matters : The whites of eggs diflolve or mingle with the former, but are 
 
 coagulated by the latter and rendered indiffoluble : Some other animal matters 
 alfo are rather hardened, than foftened or diffolved, by boiling Water. 
 
 Water dots not diffolve or unite with earths, ftones, metals, fulphur, bi- its aftion on 
 tumens, nor any mineral body that is not manifeftly faline; nor vegetable oils °7 s,varni ^ ies » 
 
 or Refins, or animal fats It extrads however ionie of the finer parts or 
 
 the effential oils of vegetables, fo as to become inspregnated with their flavour: 
 
 Hence the fmell and tafte of diftilled Waters. Oily and refinous varnifhes, 
 and oil-paintings, if a little warm Water is luffered to lye upon them for fome 
 time, or if long expofed to the weather, loie their luftre, and are at lall 
 deftroyed. The Prince of Heffe had the roof of his orangery painted at great 
 expence by Dagly, after feeing, as a proof of the goodnefs of his varnifh, 
 
 Water boiled over a coal-fire in a veffel of varnifhed paper: The varnifh how- 
 ever, which flood this teft, was deftroyed by the weather in a few years. 
 
 L 1 
 
 Cold 
 
E 
 
 R. 
 
 j2 58 W A T 
 
 Water. Cold Water corrodes alfo fome metaliic bodies, Copper, Iron, Brafs, Lead, 
 v— -v—=* Tin v as we fee in the pipes and cocks of water-works, and in fundry water- 
 On Metals, machines. It is obfervable, that Iron and Sulphur, on each of which, fepa- 
 lately, Water has no confiderable a&ion, if mixed together and moiftened 
 with Water into the confiftence of pap, grow hot, and even burft into adual 
 flame. This fluid extracts fo much from the Regulus and from the glafs of 
 Antimony, as to become emetic : By Handing for a night in a copper veffel, 
 without heat, it contrads a difagreeable cupreous tafle. Iron, heated red 
 and quenched in Water, communicates a manifeft tafte, efpecially if the ex- 
 tindion is feveral times repeated ; and Quickfilver boiled in Water is laid to 
 impregnate the liquor with the anthelmintic and other virtues of that mineral. 
 Langelot, by grinding Gold for a length of time, in a particular mill, re- 
 duced the metal to fuch a degree of tenuity as to remain fufpended in Water, 
 and Stones. Stones alfo in certain circumfrances are fubjed to the adion of this fluid. 
 
 How often do we meet with Stones excavated by the dripping of Rain ? how 
 fmooth are they made in rivers by the attrition of the Water? how crumbly 
 do the hardeft Stones become, by repeated ignition and extindion in Water ? 
 All the Stones and Earths which burn into Quicklime, are, in that Hate, in 
 great part diffolved by Ample Water. 
 
 By the medi- The bodies which are not aded on by pure Water, are all dilfoluble in it 
 
 Tbftan 0t dT by t ^ e mediation of other fubflances ; particularly of alcalies or acids. In this 
 
 foke^alFbo- hght, Water may be called an univerfal menltruum ; and it is the only men- 
 dies. ftruum which can deferve that name. Glafs, Earths, the hard Stones, Flint, 
 
 Cryflal, &V. melted with feveral times their own weight of fixed alcaline Salt, 
 diffolve readily in Water along with the alcali, and may be diluted to any de- 
 gree. Sulphur alfo is made foluble by fixed alcalies ; and all metallic bodies 
 
 by the compofition of Sulphur and alcali, or by acids. Water impregnated 
 
 with fixt alcali, efpecially if the alcali is rendered cauflic by Quick-lime, dif- 
 folves Hair, Feathers, Wool, vegetable Refins ; and reduces oils and fats into 
 Sope. Sundry Oils, Refins, Ballams are likewife rendered mifcible with Wa- 
 ter, by yolk of eggs, Sugar, Almonds, and other fubflances. The moft in- 
 timate combination of oil with Water is that effiefted by fermentation: By 
 this procefs they are united into one apparently homogene fluid, an inflamma- 
 ble ipirit Water and this fpirit mingle readily together : But if either of 
 
 them is previously combined with certain other bodies, they either will not 
 unite at all, or not without letting go the fubflance which they held before in 
 folution. Thus if Water be impregnated with fixed alcaline Salt, inflamma- 
 ble fpirits, however fhaken with the folution, will not mingle with it, but float 
 diilinct upon the furface. On the other hand, if certain neutral Salts be dif- 
 iolved in the Water, the Water will readily mingle with inflammable fpirits* 
 and throw off the Salt, whence the ufe of vinous fpirits in promoting the cry- 
 stallization of Salts : And in like manner if refinous bodies are diffolved in 
 Ipirit, the fpirit will let the Refin go, and unite with Water. 
 
 Eaith left ir, The purelt of the common Waters leave in diflillation a confiderable portion 
 diitUiation. of earthy matter: If the diftilled Water be diftilled over again, it leaves a little 
 more earth, and this fucceffively for a great number of times. Boyle relates, 
 that an ounce of Water, cautioufly diftilled over, in glafs veffels, two hundred 
 
 1 times,, 
 
Water. 259 
 
 times, yielded fix drams of a white, light, infipid earth, fixed in the fire, andWA t £ r« 
 indifioluble in Water. Newton and others fuppofe the Water in thefe experi-i'— — v— — ' 
 ments to be really converted into earth : Boerhaave fufpedts the earth thus 
 obtained to be no other than dull that had been floating, in the elaboratory 
 though I have never obferved luch dull to be white, like the earth left in the 
 diflil lation of Water. If the Water be evaporated in broad, fhallow, open vef- e,evatecJ , in 
 fels, the refiduum is much lefs than when diftilled in clofe ones. Even t i ie ev ‘ 1 P oral;ion ‘ 
 Spring- waters which plentifully incruftate tea-kettles with a ftony matter, 
 leave little or no earth on being boiled away with a large furface expofed to 
 the air. 
 
 The purity of Water is judged, from its limpidity, and want of fmell and Marks of the 
 tafte i from its fparkling or emitting air bubbles on being poured into a glafs ; purity of Via- 
 from its comparative lightnefs; from its depofiting no Pediment in (landing ; u ' 
 from its foon growing hot, and fcon becoming cold again, comparatively with 
 other Waters; from its being comparatively warm in winter, and cold in rum- 
 mer ; from its leaving little or no refiduum on being evaporated or diftilled ; 
 from its eafily lathering with lope, boiling pulle tender, and bleaching linen 
 white-, and from its readily palling through the body when drank. To which 
 may be added, that the bell Waters are thofe which run through flinty or 
 fandy grounds, and from eaft to weft. 
 
 Some have endeavoured to correct impure Waters, by boiling, fuffering Impure Wa- 
 them to fettle, then decanting, and repeating thefe procefies feveral times : By ters correfted. 
 fuffering the Water to putrefy, then decanting and putrefying it again : By 
 boiling it with waffled fand, and afterwards filtering : By boiling it, and after 
 fettling, adding a little Spirit of Vitriol : By analyfing the Water fo as to dif- 
 cover the offending matter, and then precipitating that matter by its contra- 
 ries. Thislaft method appears to be the bell and moft effectual With re- Prefer vatioa 
 
 gard to the prefervation of Water, open wooden vefiels fhould never be em- of Waters, 
 ployed for that ufe ; for in thefe it foon corrupts. In glafs vefiels, well corked 
 down and cemented, good Water will keep for ages. A fmall addition of 
 Spirit of Vitriol or Spirit of Nitre will preferve Water from putrefaction : At 
 the time of ufing, the acid may be faturated and rendered innocent by a little 
 Salt of Tartar. See page 251. 
 
 L 1 2 
 
 PART 
 

 
 PART II. 
 
 CHEMICAL HISTORY 
 
 OF THE 
 
 VEGETABLE KINGDOM. 
 
 SECTION L 
 Of VEGETABLES in general. 
 
 E G ETA B LE S are bodies of a regular organic ftrutflure, ana- 
 logous in fome degree to that of animals. They are furnifhed 
 with a variety of veffels for receiving, tranfmitting, perfpiring dif- 
 ferent fluids-, with orgam, by which, the aliment they imbibe from 
 the earth, from water, or from the air, is changed into new forms, 
 into juices peculiar to particular plants. No art can prepare or extract from 
 the fubftances by which vegetables are fupported, products in any refpedl fimi- 
 lar to thofe elaborated in the bodies of vegetables themfelves. Diflimilar 
 plants, nouriflied by one and the fame foil ftill preferve their fpecific diffe- 
 rence?, not only in theirexternal form, but in their intrinfic qualities. 
 
 DifFerefrces in There are, however, very confiderable differences in the quality of one and 
 quality, from the fame plant, from the foil, climate, feafon, and other like circumftances. 
 foil, climate, qq ie fi ner aromatic herbs, naturally produced in dry, fandy grounds, if re- 
 moved into, moifl: rich ones, increafe in bulk, but lofe greatly of their fra- 
 grance^ 
 
 Vegetables 
 
 w 1,— > _ n — ».i _u 
 
 Struffure of 
 vegetables 
 
Vegetables in general 
 
 grance, as if their a<5tive principles were exhaufted in a luxuriance of growth {<z'\ 
 Immoderately rainy feafons occafion a like alteration without change of foil 
 The intenfely bitter Colocynth, a native of Perfia, almoft entirely lofes it: bit* 
 ternefs when raifed on our hotbeds, and grows to ten, fifteen, twenty times 
 its natural fize {b). 
 
 (tf) Exhaujied in a luxuriancy of growth.] It 
 is a common obfervation, that trees which 
 fpread luxuriantly into branches, bear little 
 fruit in companion with thofe of the fame 
 kind which are lefs exuberant: Hence art, 
 by Hunting their growth, increafes their fer- 
 tility, and at the fame time improves the 
 quality of the fruit. Mr. du Hamel fup- 
 pofes, with great probability, that the im- 
 provements made by grafting proceed wholly 
 from the check given to the increafe of the 
 woody part : and hence he infers, that the 
 heft bearing trees muft be thofe where the 
 graft is fo remote from the nature of the 
 Hock, as to be but juH fupported or kept 
 alive by it. 
 
 (b) Spontaneous vegetables .] A due attention 
 to the circumHances in which particular ve- 
 getables are fpontaneoufly produced, leads 
 directly to the fure and fuccefsful means of 
 cultivating them by art. Linnaeus juflly 
 obferves (in a curious paper upon this fub- 
 je£t in the firft volume of the Swedifh Adis) 
 that the diredtions given in many books 
 of gardening are founded in empyricifm 
 or random practice ; and that it is from 
 mild plants alone that a rational method of 
 culture can be deduced ; that all plants 
 grow fomewhere wild, and that the bufinefs 
 of art is to imitate their natural climate. By 
 climate is underflood the joint concurrence 
 of earth, air, water and heat. 
 
 The earths or foils in which vegetables 
 grow, are far from being the Ample bodies 
 mentioned under that head in the foregoing 
 
 _ D O 
 
 part : They are compounded of all the 
 kinds of mineral earths, and of that into 
 which animal and vegetable fubflances 
 themfelves are refolved by putrefaction, 
 blended together in various proportions. 
 They may, neverthelefs, be commodioufly 
 ranged, in regard to the prefent view, into 
 fourclaffes, according to the particular in- 
 gredient which prevails in the compofltion : 
 (i.) Clayie, (2.) chalky, (3.) fandy, in- 
 cluding thofe which abound, either with. 
 
 fand itfelf, or with fuch ether earthy or 
 flony particles as do not in the leaft imbibe 
 or are affected by water; and (4.) black 
 vegetable and animal mould. Each of 
 thefe foils produces plants peculiar to itfelf, 
 and which degenerate or perilh in others. 
 It is on fandy hills that the Fir and other 
 reflnous trees attain to their vigour, and 
 Hied their Turpentines and Balfams: The 
 Galeopfes, as the above-mentioned author 
 obferves, are the natural growth of black 
 earth, and die in fand, wbilfl Ornithopus 
 flourifhes in fand, and perifhes in a black 
 mould. 
 
 Under air may be included the viciflitudes 
 of lblar light diffufed throughout the atmo- 
 fphere ; which light teems to affect vege- 
 tables independently of heat, and in a man- 
 ner hitherto inexplicable. All plants grow 
 weak and flender in the confined air of hot- 
 houfes, and much more fo if the folar light 
 is excluded. Plants whofe flowers are na- 
 turally the moft odoriferous, if raifed in a 
 perfectly dark place with all the advantages 
 of warmth, moiffure, &c. either do not 
 flower at all, or bring forth flowers which 
 have hardly any fmell. The Jafmine-tree 
 whilft it covers the outfide of a wall with 
 its fragrant flowers, is not obferved to pro- 
 duce a Angle one upon fuch branches as have 
 forced their way within, even into a warm, 
 an airy and a light room. High hills in diffe- 
 rent parts of the world, the Lapland crags, 
 the Alps, Olympus, and Ararat, bring forth 
 fimilar plants, many of which are never met 
 with in lower grounds. Thefe plants grow 
 extremely quick, nature making amends for 
 their fhortnefs of furnmer, by a continual 
 agitation and renewal of air : They are 
 {mail, but loaded with innumerable feeds, 
 Removed into gardens, they grow more 
 flowly to a larger fize, but abort, or pro- 
 duce little fruit. 
 
 River, Aagnant, fpring, and tea-waters, 
 and watery and dry foils, have each their 
 peculiar plants : Succulent plants rot from 
 the quantity of water which many others. 
 
262 Vegetables/// general . 
 
 Vegetables. When mineral Salts abound in the foil, they are in part imbibed by the 
 ^ , »v ■ »/ plant, and appear to be unfubduable by its digeftive powers. Hence vege- 
 tables produced in nitrous grounds, or in fuch as have been largely dunged, 
 
 are 
 
 require. It is obfervable, however, that 
 land as well as aquatic vegetables may be 
 .railed and fupported for a length of time, by 
 placing the little roots, wafihed clean from 
 earth, in water alone. It feems as if water 
 and air, or the contents of waters and of the 
 atmofphere, were univerfally the immediate 
 matter which affords aliment to vegetables ; 
 as if the earth ferved only as a matrix for 
 vegetables to keep them firm, and to pre- 
 serve moifture about the roots ; as if the 
 difference of foils con filled wholly in their 
 being more or lefs foft or compact, fo as to 
 be eafily or difficultly penetrated by the ten- 
 der roots, and in their more or lefs readily 
 imbibing and effectually retaining water. 
 Thus clay abforbs water very flowly and 
 difficultly, its particles expanding in pro- 
 portion as they are moiftened, fo as to pre- 
 vent the further progrefs of the liquor : If 
 water be poured into a cavity made in a 
 lump of dry clay, great part of it evaporates 
 without being foaked in. Chalk on the 
 other hand very quickly imbibes water, 
 tranfmits it to every part of the mafs, and 
 does not eafily let it go ; whilft fand fuffers 
 it to percolate inftantaneoufly through the 
 interftices of the grains, without imbibing 
 any into its fubftance. 
 
 With regard to heat, the plants of the 
 torrid zone require, according to Linnaeus, 
 between the fiftieth and fixtieth degree of 
 Fahrenheit’s thermometer; thofe of the 
 temperately warm, as the fouthern parts of 
 Europe, the Cape, Japan, China, between 
 the thirtieth and fortieth ; thofe of the tem- 
 perately cold, not above thirty-eight. Thefe 
 feem to be nearly the mean degrees of heat 
 ot the refpedlive climates. The plants of 
 cold climates will not bear the heat of warm 
 ones, any more than thofe of the warm can 
 fupport the cold : Some of the Cape plants 
 in the heat of the torrid zone, grew at firfl: 
 amazingly, but foon after they loft their 
 leaves, and were difficultly kept alive. In 
 this, however, there is a confiderable lati- 
 tude : Plants may be raifed in a climate not 
 their own, provided the difference is not 
 very great; by degrees they become as it 
 
 were naturalized to it; if once they have 
 produced feeds, thefe feeds are much lefs 
 apt to mifearry, and produce hardier plants 
 than fuch as are brought immediately from 
 their native country. Tobacco, from feeds 
 of our own growth, ripens a month fooner 
 than fuch as is raifed from foreign feeds. 
 
 It was by following nature, that the inge- 
 nious botanift above-mentioned has been 
 fo fuccefsful in bringing up the vaft variety 
 of plants that have fallen under his care. 
 The rubus caule unifloro foil is ternatis was 
 fome time ago, he tells us, thought incap- 
 able of being raifed about Stockholm, till 
 attention to its natural climate taught to 
 keep it covered with fnow during the winter 
 and great part of the fpring. Mufa, the 
 moll fpecious plant in nature, had flood 
 near an hundred years in the Dutch botanic 
 garden, and could not be made to blow : 
 On confidering that its native country is 
 Surinam, where the weather is dry for one 
 half year and rainy the next, it was kept 
 long without water, and afterwards kept 
 watered abundantly : It now flowered, and 
 perfedfed its fruit ; and by the fame manage- 
 ment another Mufa was made to flower the 
 next year. 
 
 He obferves, that we can eafily imitate 
 nature in regard to earth, water, and the 
 degree of heat ; and wifhes we could equally 
 imitate her in the renewals and agitations of 
 air. This alfo it is in the power of art to 
 effedl. The principle, that warm air af- 
 cends above cold, affords means of obtain- 
 ing conftant changes and fucceffions of air 
 wherever there is warmth and cold. 
 
 Dr. Hales has applied this principle to 
 the improvement of common hotbeds. If 
 an aperture is made in the top of one end 
 of the frame, and at the bottom of the 
 other, and a descending pipe inferted into 
 this laft, a flream of frefh air will pafs con- 
 tinually over the furtace of the bed. This 
 air may be warmed before-its ad million, by 
 carrying the pipe, that conveys it, through 
 the hot dung. 
 
 What is here effedted by the heat of 
 dung, may be done i-n hot-houfes by that of 
 
 fire. 
 
Vegetables in general . 
 
 are often found to participate of Nitre ; and thole on the fea-coafts, of marine 
 Sait, though no marks of either of thole Salts can be dilcovered in other 
 plants of the fame fpecies raifed in different foils (c). From inattention to, 
 this circumftance, fome of thofe who called chemillry in aid for the exa- 
 mination of vegetables, have erroneoufly aferibed to all the plants of one 
 fpecies, laline ingredients which had been cafually abforbed by an individual. 
 
 Plants differ likewife remarkably in their quality at different periods of their; 
 growth. Thus lundry roots, which examined early in the fpring, are found to 
 be highly aromatic (d), become lefs and lefs fo in proportion as tire leaves and 
 
 (talks 
 
 263 
 
 Vegetables. 
 
 fire. A pipe, heated by the fire, and 
 reaching to a confiderable height in the 
 houfe, will occafion a continual circulation 
 of the air in the houfe, that which is warmed 
 in the pipe afeending, whilft the colder air 
 at the bottom comes in to lupply its place, 
 and receiving warmth from the tube, attends 
 in like manner, and this uninterruptedly 
 whilft the heat continues. If the lower part 
 of the pipe is made to communicate with 
 the externa] air, it will bring in frefh. If 
 the fire-place opens, immediately or by a 
 pipe, into the houfe, the colder part of the 
 air at the bottom will pafs off through the 
 fire (for fire requires a large quantity of air 
 for its fupport,) whilft frelh air is brought 
 in and warmed by the other pipe. 
 
 Stronger and more fudden agitations of 
 air, fufficient to raife a moderate wind a- 
 mong the plants, may be obtained occafio- 
 nally by mechanic impulfe. I have made 
 the outer and inner doors of the room, with 
 a proper cavity between them, ferve for a 
 ventilator, the cheek which bounds the ca- 
 vity on one fide being made of a circular 
 turvature, that the inner door, in its motion 
 backwards and forwards, may fit clofe to it 
 all the way. The inner door is furnifhed 
 with a valve at bottom, which on pulling 
 the door backwards receives a part of the 
 air of the houfe into the cavity, and with 
 another at top, by which, on pulhing the 
 door forwards, the air is forced out again 
 with ftrength enough to give a confiderable 
 Ihake to almoft all the plants in a large 
 hot-houfe. The outer door alfo is fur- 
 nilhed with valves, through which, by a 
 few reciprocations of the inner door, the 
 external air is plentifully pumped in, or the 
 internal air driven out, all the valves being 
 made to open occafionally outwards or in- 
 wards, and lecured on either fide with but- 
 f'ops. 
 
 (c) Vegetables imbibe Salts from the foil ■'l 
 HenckeJ, in his Flora faturnizans , carries this 
 point fo far, as tofuppofe that plants growing 
 about mines or in metallic countries, ab- 
 forb from the earth particles of the feverai 
 metals whofe ores are there to be met with, 
 and that plants are fometimes thus naturally 
 impregnated with Silver and with Gold, 
 as well as with the bafer metals, and with 
 the poifonous metallic body Arfenic. He 
 mentions fevera! fabulous ftories in proof of 
 this opinion. There is not one well-atteft- 
 ed example of any metallic fubftance being 
 difeovered in vegetables, except Iron ; of 
 which a minute portion has been found in 
 ail the vegetable matters that have been 
 examined with that view, whatever kind 
 of foil they were produced in. See p. 76. 
 
 The fame celebrated chemift imagines, 
 that roots or feeds planted in earths that 
 have been impregnated with colouring mat- 
 ters, will imbibe the colour, and tranfrnit 
 it unaltered to the flowers. This alfo is 
 extremely queftionable. If the ftems indeed 
 of fundry white flowers, as the Lily, be 
 placed in certain coloured liquors, as the red 
 or purple juices' of berries, lb much of the 
 juice is Laid to arife in a few hours thro’ the 
 ftem into the veflels of the flower, as to va- 
 riegate it with ftreaks of its own colour. 
 But when the plant is taken entire, and its 
 roots let in the fame coloured liquors, the 
 flower receives from them no vifible tinc- 
 ture: The colouring matter in one cate 
 palling barely through the tubulous liern, 
 whilft in the other, it paffes through the 
 whole vafcular fyftem, and is changed and 
 affimilated by the digeftive powers of the 
 plant. 
 
 (r/) Roots , in fpr'mg . ] The roots of plants 
 have been generally fuppofed to be in their 
 
 greateft 
 
264 
 
 Vegetables. 
 
 Their native 
 -principles ; 
 
 T urn. 
 
 Vegetables in general, 
 
 (talks arifeu The leaves in the mean time grow ftronger and Wronger, till the 
 flowers are ready to burft forth, and then begin to lol'e of their fragrancy, as if 
 the finer and more grateful parts were tranfmitted to the flowers and feeds. 
 How different are the common culinary herbs at different ages ; and fruits in 
 their different dates of maturity. 
 
 NATIVE PRINCIPLES of VEGETABLES. 
 
 THE fubflances naturally contained in vegetables, and feparable from them 
 by art, are, (1.) Gum, (2.) Refin, (3.) a fubtile Oil, (4.) Camphor, 
 (5,) 3 grofs Oil, and (6.) a faline matter; together with (7.) Phlegm or Wa- 
 ter, intimately blended with thefe, and which ferves as a vehicle to dilute and 
 fit them for circulation ; and (8.) an earthy fubftance, which is the bafis of 
 ail vegetable bodies, the principle on which their firmnefs and folidity depends. 
 
 Gums are infipid and inodorous fubflances, foluble in water into a vifcous 
 or glutinous liquid, not acted upon by vinous fpirits or by Gils(e), not vola- 
 tile in the heat of boiling water, not fufible or inflammable in the fire. They 
 are commonly called Mucilages when foftened with water, or when confidered as 
 blended with the other principles of vegetables ; and Gums , when feparated in a 
 pure folid dry (fate. 
 
 greateft degree of perfection in the autumn, 
 when the leaves begin to fall off: But this 
 appears rarely, if ever, to be the cafe. 
 Thus much feems univerfally to obtain, 
 that when plants have run up to flower, the 
 roots prove much weaker in fmell and tafte, 
 and their juices more crude and watery than 
 before that period ; that after flowering, the 
 roots of annual and biennial plants continue 
 to grow more and more effete till they pe~ 
 rifh ; and that thofe of perennials do not 
 recover their vigour till the enfuing fpring : 
 It is when the root is going to pufh forth 
 its firft leaves, that it is ffrongeft in medici- 
 nal as well as vegetative power. Whether 
 biennial roots are moft vigorous at the fall- 
 ing of the firft year’s leaves, or the (hooting 
 of the next, is not quite fo clear. 
 
 The moft perfect ftate of the leaves of 
 plants is faid to be juft before the appearance 
 of the flower. This rule alfo is very far 
 from being general : Perhaps it holds prin- 
 cipally, it not lolely, in the herbaceous 
 plants, or thofe which die to the ground in 
 winter. The leaves of Mint, and liindry 
 other aromatic herbs, difcover in the fpring 
 ■very little ot the ftrong flavour by which 
 they are fo eminently diftinguifhed in their 
 more advanced ftate ; vvhilft on the con- 
 trary, thofe of the Sweet-briar, and tome 
 
 Resiks 
 
 other odoriferous fhrubs, lofe much, before 
 they flower, of the fragrance which they 
 had in the fpring. The young buds, or 
 rudiments of the leaves of the black poplar 
 tree have a ftrong fragrant fmell approach- 
 ing to that of Storax, and yield, on a che- 
 mical analyfis, a refinous extradft not greatly 
 different from that valuable exotic Refin : 
 By the time that the leaves have attained 
 to their full growth, their fragrance is ex- 
 haufted. ThefineftTea, according to the 
 accounts of travellers, is the earlieft leaves 
 of the Shrub, gathered whilft they are 
 young; thofe which fucceed them, and the 
 firft ones when grown old, having lefs and 
 lefs of the admired flavour. 
 
 (e) Gums not acted upon by Oils.] Though 
 pure dry Gums are not mifcible with, or in 
 the leaft affeefted by Oils, yet when foftened 
 with water into a mucilage or thick liquid, 
 they unite eafily by nature or agitation, 
 with Oils both expreffed and diftilled, into 
 a milky or butyraceous compound ; which 
 may be largely diluted with water, without 
 any reparation of the Oil and Gum. From 
 this property of Gum, we ate enabled to 
 mingle oily and refinous bodies with watery 
 liquors fer medicinal ufe, more effectually 
 than by any other jpeans as yet difeovered. 
 
Vegetables in general. ± 6 
 
 Resins are foluble in vinous fpirits and in Oils, not aCted upon by water, Native 
 not volatile in the heat of boiling water, fufible in a fmall degree of heat, and PluNCiPLESl 
 readily inflammable on the contact of any flaming or ignited body : Of them- 
 felves they have no fmell •, but they often retain, or have induflrioufiy pre- 
 fer ved in them apart of the odorous principle, and are neverthelefs looked 
 upon as pure Refins. In their liquid Rate, they are called Balfams *, and when 
 combined with any confiderable proportion of Gum, Gummy -refins. 
 
 The Subtile Oils are fapid and odorous, foluble in Spirit of Wine, mif- Effential Oil, 
 cible with the grofler Oils, not mifcible with water, totally volatile in the heat 
 of boiling water, very readily inflammable. It is in thefe, that the odours of 
 almoft all vegetables, and of many the tafles alfo reflde ; whence they are 
 called Effential. The Oil itfelf however is not the immediate principle of 
 fmell : It contains a far more fubtile fubftance, of which the Oil is only the 
 matrix, on which the fmell wholly depends, and whole particular nature is 
 wholly unknown. If an odorous Oil be expofed for a length of time to the 
 air, it will alrnofl entirely lole its fmell without fuffering any confiderable di- 
 minution of its weight (/). 
 
 Camphors are lblid concretes, foluble in vinous fpirits, in Oils, and in mi- Camphor, 
 neral acids, particularly the nitrous, not added upon by water, totally volatile 
 in the heat of boiling water, eafily fufible, highly inflammable, fubliming 
 unchanged in clofe veffels, without leaving any feces. Their folubility in Aqua 
 fortis, and their totally arifing not only in diftillation with water, but when 
 committed to the fire without any addition, readily diftinguifh them from Re- 
 fins and coagulated Oils, with which they have often been confounded. They 
 have always a ftrong pungent fmell, refembling that of the fubjeCt, and do 
 not lofe their fmell like effential Oils, but retain it fo long as any of the Cam- 
 phor itfelf remains unexhaled. 
 
 The Gross Oils are infipid and inodorous, not mifcible with water orExprefled 
 with vinous fpirits, but readily with effential Oils, not volatile in the heat of OBs, 
 boiling water, inflammable in the fire. Thefe are ufually extracted by ex- 
 preflion, and hence diflinguifhed by the name of Expreffed or Expreffible Oil. 
 
 The native Salts of vegetables have the general characters of ialine bodies, Sale* 
 tafle, and folubility in water : Some diifolve likewife in Spirit of Wine. They 
 are of different kinds, fweet, auftere and acid ; but never alcaline, all alcaline 
 Salts being creatures of art. 
 
 Gums and Mucilages are found in greater or lefs quantity in all the vege- 
 tables that have been examined. The Oils and Salt are in many deficient, or 
 in fo fmall proportion as not to be leparable from the other principles but by 
 a deitruCtive analyfis, by a degree of fire which deftroys the texture of the 
 plant, and all its native qualities. No effential Oil, and much lefs a Camphor, 
 is to be expeCted from inodorous vegetables; and no confiderable quantity of 
 faline matter from any but thole which are manifeftly very fweet or very acid. 
 
 Vege- N 
 
 (f) Odorous Oils lofe their odour in the air.] cated to the aqueous fluid, without much 
 Their fmell is likewife in great mealure im- lofs of the fubftance of the Oil. This fub- 
 bibed by water : On agitating the Oil re- tile odoriferous principle is called by Boer- 
 peatcdly with frefh parcels of water, nearly liaave Spiritus rector or the prefiding Spirit, 
 all its fmell will be by degrees communi- of plants. 
 
 M m 
 
 U-T- 
 
66 
 
 Native 
 
 Principle 
 
 Juices natu- 
 rally extra*/ 
 fated. 
 
 Extra&ed 
 
 art. 
 
 Vegetables in general . 
 
 Vegetables when arrived at perfect growth, are fubjeft, like animals, to 
 F ‘ fpontaneous ruptures of the veffels, and an effufion of their contents, and to 
 . more profufe difcharges on being wounded. The various Gums, Refins, Bal- 
 lams and gummy Refins, brought from abroad for medicinal or mechanic 
 ufes, are the natural juices of herbs, fhrubs and trees, exuding in the warmer 
 climates, fpontaneouriy or from incifions. Many of thefe kinds of produels 
 may be collected alio in our own country. Thus, the Cherry and the Plum- 
 tree bleed in lummer a glutinous fluid, which on the exhalation of its aqueous 
 parr, concretes into a folid Gum *, and thus the Pine and the Fir fhed their 
 balfamic or oily and refinous juices. Our Poppies bleed Opium from their 
 heads, Angelica, Mafterwort, Lovage, &c. aromatic Gummy-relins from 
 their roots. 
 
 by The active principles of vegetables are feparable more effectually and more 
 perfectly by art, not only from the grofs earthy matter, but from admixtures 
 of one another. As gummy and faline fubftances diffolve in water, they may 
 be extracted from all the plants that contain them, by infuflon in that men- 
 ftruum •, aud in like manner, effential Oils and Refins are got out by vinous 
 fpirits : Where oily and refinous matters are in large proportion, they are 
 fometimes feparable from the fubjeCt by boiling it in water, the Oil or Refin 
 melting out by the heat, andarifingto the furface, indiffoluble in the aqueous 
 liquor : Effential Oils and Camphor, which exhale in the heat of boiling wa- 
 ter, may be collected in the watery vapour, pure from all the other principles 
 of the plant. By thefe operations, the native juices of all vegetables, the 
 principles in which their fmell, their tafte, their medicinal activity, and their 
 colours (g) refide, are obtained unaltered : The plant Fill preferves its original 
 form and ltruCture, though robbed of all its peculiar qualities. 
 
 I. GUMS 
 
 (*) Colours . ] Though many vegetables 
 give out their colours, along with their 
 fmells and taftes, to watery or to fpirituous 
 menftrua, or to both ; there are not a few 
 whofe colour is extracted neither by one nor 
 by the other, nor by a mixture of the two ; 
 the blue flowers of Cyan us for inftance. 
 And indeed of the greater part of vegetable 
 colours it is hard to fay whether they de- 
 pend upon a refinous or a gummy matter, or 
 on fome diftinft principle. 
 
 Water impregnated with certain faline 
 fubftances extracts the colouring matter of 
 fundry vegetables more effe&ually than' 
 pure water could do: A fubfequent addi- 
 tion of certain other Salts renders it incap- 
 able of keeping in diffolution thofe particles 
 which it had before taken up, and which of 
 courfe muft now fettle by degrees to the 
 bottom. Thus, if to a yellow decoClion 
 of Turmeric or a red one of Madder roots,, 
 made in a watery folution of fixed alcaline 
 
 Salt, we add a proper quantity of folution 
 of Alum ; the yellow particles of the one 
 and the red of the other will feparate and 
 fubfide, and leave the liquor clear. At the 
 fame time, the acid of the Alum being ab- 
 forbed by the alcaline Salt, the aluminous 
 earth falls down with the colouring matter, 
 and dilutes and brightens the colour. Thefe 
 kinds of preparations are commonly called 
 Lakes. 
 
 On what principle the tinging matter is 
 here precipitated is not known. It feems 
 as if the tinging particles themfelves had 
 fuffered an alteration from the a&ion of the 
 two Salts ; for though the liquor remaining 
 after the precipitation (which is no other 
 than a folution of vitriolated Tartar) gains 
 no colour from the Lake, it extrafts a fuffi- 
 ciently deep tin<5hire on digefting it with a 
 frefti parcel of the fubjedf which the Lake 
 was made from. 
 
 Solution of Alum precipitates likewife 
 
 many 
 
Vegetables in general. 267 
 
 I. GUMS and RESINS. 
 
 W HE N Refins or eflential Oils are intimately blended with gummy andQ UMS ant | 
 faline matter, as they generally are in vegetables, a part of the Refin R E sins. 
 
 or Oil will difiolve in water along with the Gum, and a part of the Gum will t t 
 
 diffolve in Spirit of Wine along with the Refin. Hence fpirituous tinctures Tinaures and 
 made from plants are not purely refinous, but contain a part of their mucilage, in f uf io n3 - 
 whillt watery infufions participate of the Refin and Oil, and confequently of 
 the tafte, fmell, and medicinal virtue, redding in thofe principles. There is 
 fcarcely any vegetable, however refinous, that does not give out fome part of 
 its virtue to water. 
 
 If plants be infufed or boiled in water till that menftruum has extraded ail Pure refinous 
 it is capable of doing, and afterwards digefted in Spirit of Wine, the ipirituous tinctures* 
 tindure thus obtained, will be merely refinous : Thefe kinds of tindures made 
 from odoriferous or aromatic vegetables, have generally little flavour of the 
 fubjed, the more fubtile part of the Refin, or eflential Oil, being either previ- 
 ously diflolved by the water along with the gummy or faline matter, or difll- 
 
 pated during the boiling In like manner, if Spirit of Wine be applied at Pure gurrufty 
 
 firfl, it will dilfolve the Refin and the Oil, and leave undifiolved a part of the * n f u fi° ns - 
 Gum or Mucilage, which may now be extracted by water, pure from any 
 other principle, perfedly infipid and inodorous. 
 
 The watery extradions from vegetables are named infufions or decoffions, ac- Genera j ^ 
 cording as they are prepared by macerating or infufing, or by boiling the plantfervationt. 
 in the water : The fpirituous are named tindlures, efjences , or elixirs , according 
 as they have a lefs or greater degree of confidence, or are lefs or more loaded 
 with the loluble parts of the fubjed; ; when as thick as the native balfams or 
 refinous juices, they are called fpirituous balfams. The method of making thefe 
 preparations is too familiar to require any explanation in a work of this kind : 
 
 What fubftances are adapted to one or the other treatment, will appear from 
 the examination of particular bodies in the following fedions. We fhall here 
 only obferve in general, that though vinous fpirits extrad the odorous part of 
 vegetables far more perfectly than water, yet the fpirituous tindure difcovers 
 frequently lefs fmell than the watery infufion, the fpirit feeming to cover or 
 conceal the fmell ; that both water and fpirit difiolve molt readily the finer and 
 more grateful parts of plants ; that heat promotes the adionof both menftrua, 
 and enables them more Ipeedily to take up, along with thole, the grofler and 
 more ungrateful matter. If Sena, for infiance, be infufed in cold, or for a little 
 time in warm water, the liquor will purge far more mildly titan an infufion 
 made in hot water for a longer time, though both infufions be reduced to the 
 fame degree of ftrength, in regard to the quantity of matter diflolved in them* 
 by a fuitable evaporation of the fluid. 
 
 By 
 
 many vegetable colours that have been ex- On what foundation this happens we do not 
 traded by water alone ; and in this cafe know. The whole affair requires a more 
 alfo, a part ot the earth of the Alum falls thorough examination than has hitherto 
 down along with the colouring particles, been bellowed upon it, 
 
 M m 2 
 
2 6 8 Vegetables in general . 
 
 Gums and By totally exhaling, the fluid, the gummy or refinous matter which it had 
 Resins, taken up from the plant, is obtained in afolid form : Thefe preparations are 
 called, not Gums and Refins, as not being purely fuch, but watery and fpirituous 
 
 Watery w g Hmm y anc j refinous er.tr arts. An ex trad made by water, from a plant that has 
 U ^ previoufly undergone the action of lpirit, may properly be called Gum or Mu- 
 cilage-, and one made by fprrit, after water has performed its office, may be 
 looked upon as a pureRefin. A pure Refin may be procured alfo by evapo- 
 rating a tindure made in lpirit at firft, till it begins to grow thick, and then 
 adding a quantity of water : The Refin, indiffoluble in that menftruum, will 
 feparate and fall to the bottom, whilft the gummy parts before mixed with it, 
 remain fufpended in the water. 
 
 In the making of extracts, it is particularly necefiary to perform the evapo- 
 ration with a gentle heat : In many cafes, the liquor may at firft be kept boil- 
 ing for a time over an open fire, but as icon as the matter begins to grow a 
 littie thick, it muft be removed into a gentler heat, otherwise it will lcarce be 
 pofiible to prevent its burning to the vefiel, and contracting a difagreeable 
 empyreumatic fmell and tafte : It is now to be placed in a water-bath, or ra- 
 ther poured into fhaliow fiat vefiels, and exficcated in a warm room. 
 
 Traffic vege- In the making of extrads for medicinal ufe, from draftic vegetables, ftrono- 
 boiling is oftentimes of advantage, as it abates the violence of the medicine 3 , 
 and renders its operation more mild and fafe. Tor this purpofe, the infufion 
 or decodion of the fubjed fhould be made with a large quantity of water, that 
 the liquor may be kept the longer boiling before it grows thick : The infpif- 
 fated matter may likewife be dilfolved afrefh, and the codion and infpiftation 
 repeated. By this treatment, great alterations are made in vegetables, inde- 
 pendently of the difiipation of their volatile parts. Alarum, a ftrongemetic, 
 treated with a large quantity of water, yields an extrad which proves merely 
 purgative: If this be diftoived afrefh, and again infpiftated, it lofes its purga- 
 tive, and acquires a diuretic virtue: By a third inlpiffation, it is changed 
 from a diuretic to a fudorific. In like manner, the violent emetic power of the 
 white Hellebore, and the cathartic of the black, are mitigated or deftroyed by 
 long codion : Tobacco, from a virulent emetic and cathartic, becomes a fafe 
 pedoral, attenuant and anodyne. The milder purgatives alfo, as Sena and 
 Rhubarb, are proportionably weakened by a like treatment [h). 
 
 H. ESSENTIAL OILS. 
 
 Essential- W odorous vegetables are boiled in water for any confiderable time, 
 
 " Oms. their fmell is loft both from the plant and from the decodion, the vola- 
 
 W— ' tile Oil, in which the odour refides, being diffipated along with the fleam of 
 the boiling liquor. If the vapour which exhales, be caught and condenfed in 
 
 proper 
 
 (b) lira fi'ic vegetables corrected . ] The viru- of. the ch.etnifts, is not quite fo certain, 
 fence of draftic vegetables is undoubtedly Whatever may be in this, the preparations 
 deftroyed or abated by long continued boil- are by no means fit for general ufe, as it is 
 ingj hut that by this procefs they acquire impoffible to adjufc them to any ftandqrd ir\ 
 the excellent diuretic, pedoral, aperient point of ftrength, 
 and other virtues aferibed to them by fome 
 
V 
 
 EGETABLES tfl 
 
 general. 
 
 269 
 
 proper vefiels, as the common (till, the Oil feparates from the difbilled water, Essential 
 and arifes to the fur face or finks to the bottom according to its gravity. Where Oils. 
 
 the quantity of Oil is very fin all, it is moft commodioufly taken off with a 
 little Cotton : Where the quantity is large, it is parted from the water by 
 means of fpout-receivers and feparating glafies contrived for this tile. 
 
 Thefe Oils are obtainable only from odoriferous vegetables, but not equdly Subjefls, 
 from all of that clafs, nor proportionably to their degree of fragrance. The 
 Violet, the Lily, the Narciffus, the Hyacinth, and fome other flowers of a 
 delightful fmell, even the damafk Rofe it fell, fcarcely yield a drop of Oil, un- 
 lefs fome hundred weights are committed to the operation at once : From fuch 
 quantities I have feen, in Italy, a little Oil obtained from them all. 
 
 Eflential Oils may be confidered as little other than fubtile liquid Re fins or Analogy with 
 Balfams. By digeftion or heat, they actually change into thick Balfams, and^ s ^ ni - 
 at length into perfect, foiid, brittle Reims : Diftilied again in this flate, they 
 
 (till yield, like molt of the natural Refin?, a portion ot fluid Oil, the grofier 
 relinous matter remaining in the ftiil. By certain treatments, and by the ad- 
 mixture of concentrated mineral acids (/), a like change is producible in thefe 
 Oils inftantaneoufly. 
 
 In molt of the herbs, flowers, feeds, barks, or roots, that yield an eflential 
 Oil, the microfcope difcovers fhining relinous particles : If thefe be carefully 
 picked out and feparated, the remaining matter will no longer yield a Angle 
 drop of Oil. All herbs and trees, in proportion as- they are the more refin- 
 ous, yield the more Oil : The Larch, the Pine, and the Fir, which abound 
 with Refin, abound alfo with Oil, whilft the Birch, the Beech, and the Oak, 
 are as deficient in one as in the other. The Turpentine and Fir-tree yield the 
 molt Oil of any vegetable fubltance known : Hence the Oils of thefe are em- 
 ployed for the fophiftication of the more rare and coftly. Next follows Savin, 
 which affords an ounce and a half upon fixteen ounces. Cloves, Nutmegs, &c. 
 give the next largelt quantity : After thefe come Mint, Marjoram, Spike, 
 
 Saffafras, &c. all which yield a confiderable proportion. The Oil of Juniper- 
 berries is fold very cheap, but we mult not conclude from hence that thefe 
 berries afford any very large quantity, much the greateft part of it being 
 common Oil of Turpentine : Only about fix ounces of Oil were obtained from 
 fixteen pounds of the berries (k). 
 
 Eflential Oils refide chiefly in the rinds, fine leaves, flowers and feeds of Their feat, 
 plants, and commonly in particular cells diltributed through thofe parts. In 
 irefli vegetables, the Oil is blended with watery moilture : And hence when 
 
 recent 
 
 (/) EJfeniial Oils with acids . Thefe Oils 
 unite difficultly with alcaline Salts, but very 
 readily with the concentrated mineral acids : 
 With thefe laft they form a thick butyrace- 
 ous or. foiid concrete, which, when freed 
 from the redundant acid by ablution with 
 water, proves in many refpedts fimilar to 
 Refins : It has a refinous tafte, liquefies in 
 a fmall heat, and totally diftolves in reifti- 
 fied Spirit of Wine. A great heat and ebul- 
 
 lition, with a difcharge of noxious fumes, 
 commonly enfue upon mixing the Acid and 
 the Oil : By a hafty addition of the concen- 
 trated nitrous fpirit, moft Oils may be 
 actually fet on fire. Seepage 195. 
 
 {k) Quantity of Oil.] An account of the 
 quantity of Oil obtained from different fub- 
 ftances, may be feen in the Practical Che- 
 mijlry , page 260. 
 
270 V eg e x a b l e 8 ut general . 
 
 Essential recent plants are commited to diftillation, very little Oil is obtained in a fepa- 
 Oils. rate Dry plants yield more Oil, but here again there is another incon- 
 
 Yyjfaznzzf venience, the more fubtile, volatile and fragrant parts exhaling in the exfio 
 according as cation along with the aqueous humidity. Moft eilential Oils, however, are 
 the fubjedt isufually diddled from dry plants : The exficcation fhould be performed with 
 vfed frdh or carei noc ; n the fun, much lefs by a fire, but in a moderately warm ftiadv 
 place (/). 
 
 Of the difference betwixt the Oils obtained from recent and dry vegetables, 
 we have a notable inftance in Citron-peels. Let the frefh peel be diddled in 
 the heat of a water- bath without addition, and the dry peel with water in the 
 common manner : Compare the two Oils together, and they will be found ex- 
 tremely different •, the fird highly fubtile, volatile, penetrating, and truly ethe- 
 real ; the latter far groffer, of a thicker confidence, not near fo agreeable i» 
 fmell ortade, approaching more to the nature of Refins or Balfams, the con- 
 fidence of which lad it acquires fpontaneoully upon keeping for a few years. 
 The lame thing holds alfo, though not in an equal degree, in all odoriferous 
 vegetables : Even from frefh ones we obtain two kinds of effential Oil, one 
 groffer, and the other more fubtile. 
 
 Method of In the didillation of efiential Oils, F regard mud be had to their degree of 
 obtaining volatility or ponderofity ; feme requiring for their elevation a confiderable fire, 
 which would be injurious to others, by difiipating or altering their more fubtile 
 pares. A few, as thofe of Citron-peel, and fome tender leaves and flowers, may 
 be commodioufly drawn in a water- bath without any addition (m) but much 
 the greater number require the fubjedt to be boiled in water over a naked fire. 
 The water ferves here both as a mendruum to diffolve and difunite the gummy 
 and mucilaginous parts, in which the oily ones were entangled, and as a vehicle 
 to carry up the Oil ; as alfo, to fecure the plant from burning to the veffel. 
 The quantity of water may be about three or four times as great as that of the 
 fubjedt to be didilled. 
 
 Ufc of faline Compadt fubdances are to be previoufiy macerated in the water for three or 
 additions. four days, that the Oil may be the more effedtually extricated. To every ten 
 quarts of the water may be added two or three handluls of common Salt : This 
 not only promotes the adtion of the water, and prevents the fermentation or 
 putrefadlion, which vegetable infufions are liable of themfelves to run into, 
 but likewife increafes the weight of the fluid, renders it capable of bearing a 
 
 greater 
 
 quite colourlefs, Very light, in appearance 
 almoft like pure Spirit of Wine, exquifitely 
 retaining the native odour of the flowers, 
 Without any of that ftfong difagrceable 
 feent perceived in thofe obtained by violent 
 codtion of the plant in large quantities of 
 water. The common ftill is eafily adapted 
 to this purpofe, by fixing a hair-cloth im- 
 tnediately over the furface of the water, and 
 placing the herb upon it, fo as to arife quite 
 into the head. 
 
 { l) Exficcation of plants for effential Oil.] 
 Plants are rarely dried with us, in order to 
 increafe the yield of their eilential Oil. 
 
 (m) Dill illation of Oils in a water-bath.] 
 The efiential Oils of many odoriferous 
 plants are eafily obtained in the higheft de- 
 gree of perfection, by diftilling them with 
 the vapour of water kept fomewhat below 
 boiling. The Oil of Lavender flowers, of 
 Rofemary-tops in bloom, thus diftilled, are 
 
Vegetables in general. 2 7 e 
 
 heat, and thus enables it ter elevate more readily the groffer and more fiuggiOh £sshntia.i. 
 Oils («), _ t _ , ° IL _ s f, 
 
 Some employ for thefe purpofes other faline additions, as regenerated Sea- 
 fait, the Sal digeftivum, Glauber’s Sal mirabile, mineral acid fpirits, crude 
 Tartar, and fixed alcaline Salts. The tv/o lad are by no means to be com- 
 mended: Tartar, as containing itfelf a grofs oily matter, and being very diffi- 
 cult of folution, can at beft do little fervice ; and alcalies, though they power- 
 fully promote the refolution of the fubjedt, yet at the fame time entangle and 
 detain the Oil, forming with it a faponaceous concrete. With regard to acids, 
 
 Homberg relates, that from Fennel feeds andRofes a much larger quantity of 
 Oil was obtained when Spirit of Salt or Oil of Vitriol were added, than when 
 the lubjebts were macerated for an equal length of time without thole additions. 
 
 But if the Oil thus obtained was really in greater quantity it was liirely infe- 
 rior in quality: Thefe acids alter the quality ol all diftilled Oils, and difpofe 
 them to a refinous confidence. 
 
 Some vegetable matters, particularly the rinds of Citrons, Lemons, Oranges, By incifionv 
 yield a part of their effential Oil upon bare incifion. By this Ample procels, 
 an Oil is prepared from Citron-peel, in Italy, more fubtile and volatile than 
 that obtained by diftillation. The fruit is rolled upon a plate duck full of 
 fharp points ; by which, many thoufands of punbtures are made at once in the 
 rind, and the oily cells laid open : The Oil which thus exudes, is received in 
 a velfel placed underneath, and what dill remains in the peel is afterwards ex- 
 tradted by didillation. Hoffman relates, that the Italian Oil of Citron peel, or 
 Oleum de cedro, is fo light as to fwim upon Spirit of Wine ; but I have always 
 obferved it to fall to the bottom : Probably he made the experiment with a 
 phlegmatic fpirit. 
 
 The effential Oils obtained from different vegetables, differ from one ano- Di Terences of 
 ther, not only in fmell and tade like the vegetables themfelves, but in fun dry the Oils of 
 other refpedts. Some are fo heavy as to dnk in water ; fuch are thofe of the° lff< V? nt ve “ 
 Indian aromatics, Cinamon, Cloves, Saffafras, Sfc. Others, and indeed the seta es ” 
 greater number, fwim on water (o). The Oils of Lavender,, Balm,, Rofemary, 
 
 Savinj, 
 
 (3) Salt renders the water fufceptible of 
 greater heat.] In this intention the addi- 
 tion of Salt may poftibly be of fome ufe ; 
 but what fervice it is capable of doing 
 during the maceration does not appear. In 
 that part of the operation, it Ihou'-l feem 
 to be rather injurious, as it tends to harden 
 inftead of foftening the fubjedt, and to im- 
 pede inftead ot promoting the adtion of the 
 water. There is no occafion for any other 
 addition than plain water : The mod corn- 
 pad woods, duly rafped or fhaved, will be 
 fufficiently penetrated by maceration in wa- 
 ter, and the fubfequent diftillation with a 
 boiling heat, to give over all the effential 
 Oil they contain. With regard to the pre- 
 
 venting of putrefaction, it fliould feem, that 
 in proportion as the Salt prevents that pro- 
 cefs, it prevents the effedt expedted from 
 the maceration ; the opening, as it is called, 
 or refolution of the fubjedt here required, 
 being no other than the early ftage of a ge - 
 neral procefs which in. its advanced ftate is 
 termed putrefaction.. 
 
 (5) Gravity, of Oils.] As there are con ft- 
 derable differences in the gravity of the 
 Oils of certain vegetables, fome have 
 thought to diftinguifh, upon this principle, 
 the genuine Oils from the fophifticated, or 
 the Oil of one fubftance from that of ano- 
 ther, A further examination thews, that 
 
 the- 
 
n *7 y 
 ^ 1 ** 
 
 Essential 
 
 Gils. 
 
 ^ I J 
 
 How te be 
 kept. 
 
 Their adulte- 
 rations de- 
 tcclecf. 
 
 Vegetables in general . 
 
 Savin, if carefully diftilled, prove limpid and colourlefs, whilft that of Spike 
 is greenifh yellow ; of Thyme and Savoury, brownifh •, of Wormwood, brown 
 or greenifh black ; of common Camomile, blue; of Milfoil, fometimes blue 
 and fometimes green •, of Cloves, Cinnamon, Saflafras, at firft colourlefs, 
 changing by age to a yellowifh, and at length to a reddifh-brown colour. 
 Thole of Anifeeds and Rue congeal or become conliltent in cold weather, 
 whilft moft of the others preferve their fluidity. 
 
 Eflential Oils, as being fraught with a very volatile odoriferous principle, 
 fliould be carefully preferved from the air. They are beftkept in glafs bottles 
 fitted with ground glafs {toppers, not in a warm, but in a cool and dry place. 
 Warmth promotes not only the diflipation of their fubtile fragrant part, but 
 likewife their difpofltion to become refinoup. 
 
 The dearer eflential Oils are frequently adulterated with Oil of Turpentine, 
 
 expreflfed Oils, Spirit of Wine, ifc. An admixture of fpirit may be difco- 
 
 vered, by pouring a little of the fuipedted Oil into water : If the water grows 
 milky, and the quantity of Oil vifibly lefs, we may be fure that this adultera- 
 tion has been pradtifed : If no milkinefs appears, we may be fatisfied that the 
 
 Oil has no mixture of fpirit -Expreflfed Oils are dilcovered by adding a 
 
 quantity of fpirit, which will diflolve the eflential, and leave the exprefied be- 
 hind Oil of Turpentine is diftinguiflied by moiftening a bit of cloth with 
 
 the mixed Oil, and fetting it in a gentle warmth : The fmell of the genuine 
 Oil will foon be diflipated, that of the Turpentine remaining. The Oil of 
 Turpentine is apt likewife to diflolve the Oil painting on the bottles in which 
 thefe kinds of preparations are ufually kept in the fliops (p). 
 
 Though 
 
 the gravity can be no certain teft ; that one 
 and the fame fubject yields, at the beginning 
 and end of the diftillation, Oils more dif- 
 ferent in gravity than thofe obtained from 
 different fubjects. How nearly lome efien- 
 tial Oils, that are very diffimilar in their 
 other qualities, approach in fpecific gra- 
 vity, and how nearly the grofs expreffed 
 Oils approach to fome of the eflential, will 
 appear from the following table. T he pro- 
 portional weight of rain-water, as in other 
 
 tables of this kind, is 1,000. 
 
 Eflential Oil of Saffafras - 1,094 
 
 of Cinnamon - 1,035 
 
 of Cloves - - 1,034 
 
 of Fennel - - ,997 
 
 of Dill - - ,994 
 
 of Penny-royal ,978 
 of Cummin - - ,975 
 
 of Mint - ,975 
 
 of Nutmegs - - ,948 
 
 ofTanfy - - ,946 
 
 of Caraway Seeds ,940 
 of Origanum - ,940 
 
 Eflential Oil of Spike - •• - ,936 
 
 of Rofemary - ,934 
 
 of Juniper-berries ,911 
 of Oranges - - ,888 
 
 of Turpentine - ,792 
 
 Expreflfed Oil of Linfeed - - ,932 
 
 of Olives - - ,913 
 
 of Rapefeed - - ,913 
 
 Thefe are the gravities of the particu- 
 larfpecimens examined ; and of moft of them 
 we {hall feldom perhaps meet with another 
 fpecimen, that does not differ as much from 
 the fame Oil in the table, as that in the table 
 does from the Oil next to it. 
 
 (p) Adulteration of eflential Oils .] As all 
 eflential Oils agree in the general properties 
 of folubility in Spirit of Wine, indilTolubi- 
 lity in water, mifeibility with water by the 
 mediation of Mucilages, Sugar, or yolk of 
 eggs, volatility in the heat of boilina wa- 
 ter, &e. it is plain they may be varioufly 
 mixed with one another, or the dearer fo- 
 
 ph iff Rated 
 
Vegetables in general . 273 
 
 Though all effential Oils diftil freely along with boiling water, there areEssENriAL 
 many which cannot be elevated by the heat that boiling water communicates Oils. 
 through thefides of another veffel. If Oils already feparated from the fubjeft, xhTjThabr^ 
 be committed to diftillation by themfelves, there are few that will begin to tU( j e t0 fi re m 
 arife, till the heat has become ftrong enough to alter or deftroy their peculiar different cir- 
 flavour, and give them a burnt fmell and tafte. It is obfervabie, that the cum£ * ances - 
 moft fubtile and volatile of the effential Oils require a confiderably ftronger 
 heat to make them boil than water does (/>). 
 
 Water agitated with effential Oils, imbibes a portion of that fubtile prin- Diftilled wa- 
 ciple on which their odour depends, fo as to become notably impregnated wir.h ter$ » 
 their flavour. Hence the water, which diftils along with the Oil participates 
 always of the fmell of the plant, and of its tafte alfo, where the tafte depends 
 upon the oily principle. The diftilled waters of fome fubftances, as Cinna- 
 mon, Cloves, Cardamoms, Anifeeds, Fennel-feeds, &c. poffefs the diftin- 
 
 guifhing 
 
 phifticated with the cheaper, without any 
 poflibility of difcovering the abufe by any 
 trials of this kind. v 
 
 And indeed, it would be of little advan- 
 tage to the purchafer, if he had infallible 
 criteria of the genuinenefs of every individual 
 Oil. It is of as much importance that they 
 be good as that they be genuine ; for I have 
 often feen genuine Oils, from incurious di- 
 ftillation, and long and carelefs keeping, 
 weaker both in fmell and tafte than the 
 common fophifticated ones. 
 
 The fmell and tafte feem to be the only 
 certain tefts that the nature of the thing 
 will admit of. If a bark has in every re- 
 fpe£t the appearance of good Cinnamon, 
 and is proved indifputably to be the genuine 
 bark of the Cinnamon-tree, yet if it wants 
 the Cinnamon flavour, or has it but in a 
 low degree, we rejeCt it ; and the cafe is the 
 fame with the Oil. It is only from ufe and 
 habit, or companion with fpecimens of 
 known quality, that we can judge of the 
 goodnefs either of the Drugs themfelves or 
 of their Oils. 
 
 Moft of the effential Oils, indeed, are too 
 hot and pungent to be tailed with fafety, 
 and the fmell of the fubjeCl fo much con- 
 centrated in them, that a fmall variation in 
 this refpedl is not eaflly diftinguilhed ; but 
 we can readily dilute them to any affignable 
 degree. A drop of the Oil may be diffolved 
 in Spirit of Wine, or received on a bit of 
 Sugar and diffolved by that intermedium in 
 water : The quantity of liquor which it 
 
 thus impregnates with its flavour, or the de- 
 gree of flavour which it communicates to a 
 certain determinate quantity, will be the 
 meafure of the degree of goodnefs of the 
 Oil. 
 
 (p) Habitude of Oils to fire .] Many Oils, 
 in their firft diftillation from the fubjeCt, 
 carry up with them a portion of grofs re- 
 finous matter ; which, if too ftrong a heat 
 has been ufed in the operation, proves fome- 
 times very conflderable. On more care- 
 fully diftilling them with water a fecond 
 time, the Refill remains behind, and is gene- 
 rally found to be infipid and inodorous: 
 The Oil by this means becomes more lim- 
 pid and pure, and at the fame time is in 
 good meafure freed from any ungrateful 
 empyreumatic taint which it might before 
 have received from the fire. In this rectifi- 
 cation of Oils, whether debafed in the di- 
 ftillation itfelf or by age, fome have em- 
 ployed common Salt, Sal mirabile, and 
 other additions, which do not appear upon 
 experiment to be of any advantage. 
 
 Effential Oils, diftilled in a retort with- 
 out water, firft give over a thin fluid Oil, 
 flightly empyreumatic, a thicker one re- 
 maining in the bottom. If this be further 
 urged, greateft part of it arifes, only a little 
 coaly matter being left ; but the fpecific 
 flavour of the fubjeCt is deftroyed, and the 
 diftilled Oil has only a burnt fmell and 
 tafte, like that of the empyreumatic ones to 
 be treated of hereafter, 
 n 
 
274 Vegetables /« general. 
 
 Essential guifning tafte as well as the fmell of the fubje&s; whilfl: thofe of Rofes, 
 Oils. Wormwood, and many others, have nothing but the fmell ; the bitternefs of 
 U Wormwood, the aitringency of the Red rofe, and the purgative quality of the 
 
 damafk, refiding in a fixed matter, incapable of arifing in diftillation. 
 
 Subjects for Water receives a ftrong impregnation by this procefs, not only from thofe 
 diftaied w a- oc j orous vegetables which abound with Oil, but likewife from the more tender 
 flowers which yield no adlual Oil unlefs immenfe quantities are committed to 
 diftillation at once, as the Jafmine and the Lily. Vegetables in general, pof- 
 fefled of any confiderable fmell, flavour, aromatic warmth or pungency, o-ive 
 over thofe qualities to Water in diftillation ; whilfl: bitternefs, fweetnefs, af- 
 tringent, purgative, emetic, undtuous, mucilaginous virtues remain behind in 
 the (till. How ridiculous is it to diftil Waters, as many difpenfatories (till di- 
 red, fiom fubftances of this laft clals, which give over nothing of their virtues. 
 General ob- Waters diftilled from one ingredient are called fimple ; from more than one, 
 fervations, compound. Frelh juicy vegetables are fometimes diftilled by the heat of a 
 Water-bath, without any additional liquid ; that heat being infulficient to burn 
 or fcorch the plants, whilfl it elevates great part of their flavour along with 
 their native moifture (r). The method of performing the diftillation is too 
 
 com- 
 
 (r) Diftillation in a Water -lath.'] It has 
 been commonly fuppofed that a heat much 
 Jefs than that of a Water-bath is fufficient 
 to elevate the fragrant parts of vegetables : 
 That all thofe plants, which diffiufe their 
 adtive effluvia through the open air, will 
 give out the fame effluvia, when in- 
 cluded in clofe velfels, and expofed to a 
 heat no greater than that which obtains in 
 the atmofphere in fumrner. 
 
 Take, fays a celebrated chemift, 
 “ Rofemary frefti gathered, in its perfec- 
 “ tion, with the morning dew upon it, 
 “ and lay it lightly and unbruifed upon 
 4 ‘ the broad round plate within our little 
 “ cylindrical furnace .... Then cover the 
 “ furnace with its large conical ftill - head , 
 “ and apply a glafs receiver to the nofe 
 “ thereof. In the fire-place of the furnace 
 ■“ put a lighted coal, that does not fmoke, 
 “ and raife up an equable degree of heat, 
 “ not exceeding eighty-five degrees on 
 4 ‘ Fahrenheit’s thermometer ; and let this 
 heat be kept up fo long as any liquor 
 “ comes over .... This Water contains 
 * e the elementary Water and prefiding Spi- 
 rit of the plant, a fpirit fmall in bulk but 
 <c rich in virtue, and exhibiting the fpecific 
 “ fmell and tafte, and particular virtue of 
 44 the fubjedt ; leaving the remainder ex- 
 
 * Boerh procefs i. Sh. tranflat. 
 
 “ haufted ..... Hence we may underftand 
 “ that the various, peculiar, and often fur- 
 “ prizing virtues of plants, may be widely 
 “ diffufed through the air, * ” 
 
 I have fubmitted to this procefs Rofemary 
 and many other aromatic herbs, without 
 the promifed fuccefs : The diftilled liquors 
 in general had hardly any thing of the fine 
 flavour of the fubjedt: Even when the heat 
 of a boiling Water- bath was made ufe of, 
 there were very few plants that gave over 
 to the diftilled liquor any confiderable fmell 
 or tafte. It is by the afliftance of the free 
 ventilation of the open air, that the fun’s 
 heat robs odoriferous plants of their fra- 
 grancy ; and even when thus affifted, it 
 leaves their other adlive virtues unhurt : 
 Thefe alfo the humid air of the mornings 
 and evenings diftolves and imbibes. 
 
 Hence the different effecls, upon anima 
 bodies, of the natural effluvia or aereal in- 
 fuiions of certain vegetables, from thofe of 
 their diftilled Waters. Damafk rofes, in 
 drying, impregnate the air of the room with 
 their laxative virtue; and Red-rofe buds in 
 like manner give out their aftringency ; vir- 
 tues which never arife in diftillation, but 
 which common water and fpirit extradl 
 readily by infufion. The author above- 
 quoted mentions fome examples of this 
 
 kind 
 
Vegetables in gereral. 275 
 
 commonly known to require any particular illuftration. But it may be proper Essential 
 to obferve, that as lefs of the oil feparates in the diftillation of frefh than of ^ils. 
 dry vegetables, the Waters obtained from the former are proportionably ''—'"■v”' ' 
 ftronger than thofe from the latter : That the more compaft kinds of vegeta- 
 bles require to be cut or bruifed, and macerated or digefted for feme time in 
 the Water previoufly to the diftillation, in the fame manner as for effential 
 oils, with this difference however, that the common Salt, there made ufe of, 
 is here lefs proper, a part of its acid arifing with the Water : It has been cuf- 
 tomary to fait rofes for diftillation, in order to preferve them, without drying, 
 till a fufficient quantity could be collected : The Water diftillcd from fuch 
 rofes has often been found to retain fo much of the acid of the Salt, as to turn 
 milky with folution of Silver or Lead, and to corrode Iron. Some fubftances 
 are advantageoufly fermented for a few days, with the addition of a little Su- 
 gar and Yeaft, their fmell and virtue being by this means more effectually ex- 
 tricated and communicated to the difti lied liquor: Veronica, a plant of very 
 little fmell, and which if immediately committed to diftillation gives over no- 
 thing confiderable, yields, if (lightly fermented, a Water that fmells and taftes 
 ftrongly of the herb. The quantity of Water made ufe of muft be propor- 
 tioned 
 
 kind, without feetnlng to have duly attend- 
 ed to their confequences : For if the (hade 
 of the Walnut-tree makes the body coftive, 
 and the effluvia of Poppies procure deep ; 
 as thefe virtues are incapable of being ele- 
 vated in diftillation, does it not follow, that 
 they muft be communicated to the air upon 
 fome other principle ? 
 
 With regard to the ufe of a Water-bath, 
 though there are few vegetables that give 
 over their flavour in that degree of heat, 
 yet for thofe which do, it is undoubtedly of 
 great advantage : Fire fenfibly injures, in 
 proportion to its degree, the flavour of aro- 
 matic herbs, and thofe which are moft vo- 
 latile fuffer the moft from it. Some tender 
 flowers, as thofe of Rofemary, have their 
 fragrance impaired, by the bare mechanic 
 aCtion of watery or fpiritous liquors, inde- 
 pendently of heat, nearly in the fame man- 
 ner as it is by bruifing them. 
 
 In diftilling thefe kinds of fubjeefs, I have 
 varied the procefs, by applying, inftead of 
 Water or fpirit in their grofs form, only 
 their vapours : The liquor being poured 
 into the ftill, - a hair-cloth, ftretched on an 
 iron hoop, is let in above it, and on this 
 the frefh unbruifed flowers are lightly 
 fpread : The vapour into which the liquor 
 is refolved by the heat of a Water- bath, 
 paffing gently through the flowers, imbibes 
 their fragrance unimpaired, and condenfes 
 
 N 
 
 into a water or fpirit greatly fuperior to 
 thofe prepared in the common manner. 
 
 The foregoing obfervations point out a 
 method of improving alfo the preparation 
 of extracts. If infunons of Mint, Balm, 
 and fundry other vegetables of the aromatic 
 kind, be diftilled by a gentle warmth in 
 clofe veflels, little more than the watery 
 menftruum will arife, greateft part of the 
 flavour of the fubjeCt remaining behind in 
 the extradf. When the diftillation is per- 
 formed by a boiling heat, the whole of the 
 flavour comes over with the Water] and 
 when the infpiffation is performed in open 
 veflels, however gently, it is almoft wholly 
 abforbed and carried off by the air. Our 
 author himfelf feems to have been fenflble 
 of this in his experiments on tea ; for in or- 
 der to procure an extraCt from tea, poffeff- 
 ing the admired flavour of the leaf, he finds 
 it particularly neceffary to infpiffate the 
 infufton without communication with the 
 open air. 
 
 Thus we fee, that by diftilling many 
 odoriferous vegetables in clofe veflels, we 
 may obtain their fragrancy either in the 
 Water that diftills, or retain it in good 
 meafure in the extraCI, according as the 
 degree of heat made ufe of is ftrong or gen ~ 
 tie ; and that by evaporating them in open 
 veflels their fragrancy is in either cafe car= 
 ried oft* by the air. 
 n 2 
 
276 
 
 Veg e t a b l e s in general \ 
 
 Oils 
 
 Essential tioned to the nature of the fubjedt : Whatever quantity is added, the ddtilfa- 
 tion muft be continued no longer than while the liquor proves fufficiently im- 
 pregnated with the flavour of the ingredients. The virtues of many plants 
 come over moft plentifully in the firft runnings ; whilit thofe of others are 
 more ftrongly locked up, and l'carce begin to arife till the diftillation has- 
 been continued for fome time. Where the plant is of fuch a kind as to give 
 but a weak impregnation to the diftilled Water ; we may render the liquor 
 ftronger by cohobation, that is, by drawing it over again from a frefh parcel 
 of the fubjedt (s). 
 
 Spirit 
 
 fs) Waters made Jir anger by cohobation.'] 
 This is another of the many procefies in 
 which I have, on trial, been greatly difap- 
 pointed. Though fome of the chemifts 
 affirm, that diftilled Waters in general may 
 be rendered, by repeated cohobations, of 
 any affignable degree of ftrength, and their 
 virtues exalted without limitation f ; I have 
 not found that repetitions of thefe opera- 
 tions make any confiderable addition to the 
 ftrength even of thofe Waters, whofe ex- 
 altation by this treatment has been particu- 
 larly fpecified. 
 
 The diftilled Waters of Mint, Rofemary, 
 and other aromatic herbs, being rediftilled 
 a number of times fucceffively from frefh 
 parcels of the refpedtive fubjedts ; inftead 
 of being more and more exalted and im- 
 proved, they were on every repetition more 
 and more debafed. Some of them indeed, 
 by one cohobation, did feem to be rather 
 mended, and fometimes a fecond did hardly 
 any injury : But after this period, they all 
 received an ungrateful taint from the re- 
 peated adlion of the fire, without gaining 
 any more of the flavour of the fubjedi than 
 they had at firft. 
 
 It is not by diftillation, but by infufion, 
 that Water can be unlimitedly impregnated 
 with any of the principles of plants. Water 
 extracts by infufion the gummy parts of ve- 
 getables ; and it is a property of all gummy 
 fubftances to diffolve indefinitely in Water, 
 that is, to unite with any proportion of it, 
 I mall or large, and render the liquor thicker 
 and thicker as the quantity of gummy mat- 
 ter is increafed. When Refins or eflential 
 Oils are intimately combined with gums, 
 as they are in moft vegetables, thefe com- 
 pounds unite alfo indefinitely with Water. 
 
 f Id, procefs xvi. 
 
 Hence by macerating or infufing, in the 
 fame Water, frefh parcels of aromatic herbs, 
 the liquor takes up more and more of their 
 foluble parts, till it grows too thick to be 
 poured off, and the lofs of fluidity is the 
 only bounds to the impregnation. 
 
 In diftillation on the other hand, nothing 
 arifes with the Water but the eflential Oil j 
 and from pure eflential Oils this fluid ex- 
 tracts only a limited quantity. Salts are in 
 this refpedt fomewhat analogous to Oils : 
 When a certain quantity of Salt is diflolved 
 in Water, the liquor, though thin and fluid 
 as at firft, will take up no more : By the 
 application of heat, it may be made to dif- 
 folve a larger quantity than in the cold, but 
 all that is fo diflolved will be feparated and 
 thrown out again upon an abatement of the 
 heat. So, when eflential Oils are coagitated 
 with Water by a boiling heat, and ele- 
 vated along with it in form of vapour ; the 
 Water, condenfing again, keeps a part of 
 the Oil diflolved, and throws out the reft. 
 The Water is now faturated, and it is in 
 vain to endeavour, by any repetitions of the 
 diftillation, to make it imbibe more. 
 
 Hence the ufe of employing the Water 
 which arifes in the diftillation of eflential 
 Oils, for fubfequent diftillations of the Oil 
 of the fame fubjedt : Being faturated with 
 Oil in the firft diftillation, it diflolves none 
 of that which arifes with it in the others ; 
 and thus the produce of Oil proves propor- 
 tionably larger than if frefh Water was 
 taken. 
 
 It follows from this account, that there 
 is one cafe, in which cohobation may be of 
 fome fervice ; that when the Water is not 
 fully faturated in the firft diftillation, it may 
 be made to imbibe more by a repetition of 
 
 it 
 
Vegetables m general 1 
 
 277 
 
 Spirit of Wine, confidered as a vehicle for the volatile virtues of vegeta- Essential 
 bles, has one advantage above Water ; keeping the whole of the eflential oil. Oils. 
 that ariles with it, difiolved. Thus if Citron-peel be diftilled with redified 
 fpiric, the oil will come over diffolved in the menftruum into an uniform e 
 tranfparent liquor, poflefiing in a high degree the fine flavour of the peel : On 
 diluting this fpirit with Water, the mixture immediately becomes milky, the 
 oil feparates, and is gradually collected upon the furface. This is an ufeful 
 method of obtaining fome of the more volatile oils. 
 
 Spirit of Wine cannot be made to receive fo great a degree of heat as Wa- 
 ter : It boils and diftils much fooner, and no increafe of fire will make either 
 of them hotter after they have begun to boil. Hence the oils, obtained in 
 the above method by means of fpirit, prove more fragrant, as having under- 
 gone lefs heat, than thofe diftilled with Water. But hence alfo there are many 
 oils which this liquor is incapable of elevating: For though they are all volatile 
 in the heat of boiling Water, there are few which arife in the heat of boil- 
 ing fpirit. 
 
 The greater number of odorous vegetables give over nothing confiderable 
 £0 fpirit. If redified Spirit of Wine be diftilled over from Rhodium wood. 
 
 Cinnamon, Nutmegs, and even from fome of the more fragrant flowers, as 
 rofes and lilies, it will fcarcely difcover any fmell or tafte of the fubjeds ; 
 whilft Water brings over the whole of their flavour. The only method of ob- 
 taining a Spirit impregnated with the volatile oils of thefe kinds of fubftances 
 
 is, to diflolve fome of the oil itfelf in pure Spirit of Wine, or to ufe in the 
 diftillation a mixture of fpirit and Water. 
 
 III. CAMPHORS. 
 
 CAMPHORS are extracted by diftillation with Water, nearly in the fame C a MPHORS, 
 manner as eflential oils. From fome vegetables, the Camphor arifes at 
 firft in its proper folid form : from others, only a fluid oil diftils, from which 
 the Camphor concretes upon long Handing. It is chiefly from plants produced 
 in the warmer climates, that Camphors are obtainable ; as the tree called, 
 from its abounding with this concrete, Arbor camphor if era , the roots of the 
 Cinnamon-tree, Zedoary, Schoenanthus, Cardamon-feeds, the Oriental mint., 
 Abrotanum, Milfoil, Daify, Juniper, Rofemary, Sage, Camphorata, Laven- 
 der, Hyflop, Clary, Maudlin, Marjoram, &c. though I have likewife ex- 
 traded a true Camphor from the common European thyme. 
 
 IV. EXPRESSED OILS. 
 
 G ROSS Oil abounds chiefly in unduous feeds and the kernels of fruits, Expressed 
 as Linfeed, Rape-feed, Poppy-feeds, Almonds, Nuts, Peach-kernels, &'c. Oils. 
 
 Thefe or other like fubftances, in order to the extradion of their expreflibie -v- 
 
 q-j Method of 
 5 obtaining 
 
 it. But furely it is more advifable, to ufe endanger debafing the flavour which the 
 the plant, in fuch quantity as may give a liquor has once received by communicating 
 fufikient impregnation at once, than to more. 
 
278 V s g e t a b l e s in general. 
 
 Expressed Oil, are pounded or ground in mills into a fmooth mafs, then inclofed in a 
 Oils, canvas bag, and committed to a flrong prefs, by which the Oil is plentifully 
 forced out, amounting fometimes to above half the weight of the fubjeft. 
 Some previoufly warm the plates of the prefs, and even heat the pounded mafs 
 itfelf in a kettle, keeping it conflantly ftirring with a wooden fpatula, to pre- 
 vent its burning. This facilitates the leparation of the Oil, and if the heat is 
 frnall, does it no injury : In winter, or if the fubjedt is moift, a gentle warmth 
 is particularly neceffary, in one cafe to render the Oil fluid, in the other to 
 difiipate the humidity. Some have been accuftomed both to warm and to 
 moiften the mafs, and thus procure a fomewhat larger yield of Oil : This 
 practice is neverthelefs highly to be blamed, as the Oil thus obtained, quickly 
 fpoils and becomes rancid. 
 
 Differences All the exprefled Oils agree in their general qualities, whatever fubftance 
 from one an- t j were drawn f r0 m. There are however fome particular differences confi- 
 
 other «■* 1 
 
 derable enough to deferve notice : Thus the workmen find that fome of thefe 
 Oils, as that of Linfeed, anfwer better for varnifhes than the purer and finer 
 ones of Olives or Almonds. Moft of thefe Oils, however carefully drawn, 
 become rancid and acrimonious upon long keeping ; but there are fome, par- 
 ticularly the Oil of Ben-nuts, which continue unaltered for feveral years : 
 Hence the ufe of this Oil as the bafis of perfumes. Moil of them coagulate 
 in winter into a thick, white, butyraceous mafs ; but fome, as thofe of Lin- 
 feed and Rape-ieed, remain fluid. They are all lefs readily inflammable than 
 efifential Oils, and conlume more flowly : A pound of Oil Olive, for inftance, 
 continues burning as long as four or five pounds of Oil of Turpentine. 
 
 Seat of ex- Some fubftances contain both an expreflible and efifential Oil, as the feeds 
 preffible and of umbelliferous plants ; thofe of Anife for inftance. In this cafe, the Oil ob- 
 eflential Oils t a i ne d by expreffion generally brings forth with it a part of the eflential Oil, 
 and thus proves impregnated with the flavour of the feeds : The Oils ex- 
 preflfedfrom other vegetable matters have no particular tafte or fmell : The ex- 
 prefled Oil of the acrimonious Muftard-feed is perfe&ly void of acrimony. In 
 what parts of thofe feeds the two Oils refide, was little known or examined, 
 till the younger Geoffroy of Paris, in diflilling fome Coriander-feeds, having 
 employed, perhaps accidentally, almoft mere hufks, difeovered the true feat 
 of the eflential Oil : Experiments on other feeds alfo, of that clafs, have 
 evinced, that the eflential refides folely and wholly in the outer fkin, and 
 the expreflible Oil in the kernel of the feed. This obfervation is not how- 
 ever to be extended beyond the feeds of umbelliferous plants : Of Carda- 
 mom-feeds, it is the kernel that contains the eflential Oil and the medici- 
 nal activity. 
 
 V. ESSENTIAL SALTS. 
 
 Essential E SSENTXAL or native Salts, fo called in diftindtion from the fixed alca- 
 Salts. line Salts produced from vegetables by art, are obtained chiefly from plants 
 i — ¥ — * of the acid kind, as Sorrel. A quantity of the leaves is gathered in thefpring. 
 Method of pounded in a ftone mortar with a wooden peftle, and the juice prefled out into 
 P-P-S tinned veflels : Some warm water may be added to the remaining mafs, and the 
 
 expref- 
 
Vegetables in general 279 
 
 expreffion repeated, that the faline matter may be more perfectly extracted. Essential 
 The liquor fuffered to ftand for a day or two, depofites a thick feculence : Be- Salts. 
 
 mg then poured off clear, and paffed through a (trainer, it is fet to evaporate ' v 
 
 in a cut glafs body placed in a gentle fand heat till about one half is wafted, 
 
 or till it is reduced nearly to the confidence of a fyrup ; after which it is re- 
 moved into a cellar, and fuffered to ftand till the Salt has cryftallized. Some 
 continue the infpiffation further, put the matter into flat earthen difhes, and 
 pour fome Oil on the furface. Others expedite the cryftallization, by fetting 
 the liquor, duly depurated and evaporated, not in a cold cellar, but in a warm 
 room, where it is left to fhoot in the fame manner as Sugar Candy. The cry- 
 ftals are to be nimbly rinfed with water, and dried upon fpongy paper in a 
 gentle warmth. Several of the cryftals generally prove brownifh coloured and 
 foul : If required to be pure and white, they are diffolved in water, the dilu- 
 tion filtered, and fet to fhoot a fecond time. The faline matter remaining 
 alter the cryftallization may be diluted with the water in which the cryftals 
 were wafhed, and after due purification, fet to cryftallize again as at firft. 
 
 This tedious procefs is rarely performed ; and the nature of the Salts, ob- 
 tainable by it from different vegetables, has been little examined. The Salts 
 of acid plants are fimilar in moft refpedts to Tartar, though not as fome have 
 fuppofed, perfectly the fame : The Salt of Sorrel is manifeftly more acid, and 
 diffolves in half the quantity of water that Tartar requires. With regard to 
 the preparation of them, much depends upon the liquor being duly purified 
 from the grofs oily matter, which impedes the feparation and concretion of the 
 Salt. The fweet effential Salt of the Sugar Cane cannot be procured in its con- 
 crete faline ftate, without the addition of Lime-water during the infpiffation, 
 to promote its feparation from the undtuous matter (j). 
 
 It 
 
 (r) Effential Salts.] Stahl obferves that the 
 tedioulnefs of the cryftallization is in great 
 meafure owing to the vifeid oily matter of 
 the juice, which entangles and prevents the 
 coalefcence of the faline particles : Hence 
 he endeavours to improve the procefs, by 
 firft extracting the oily and refinous matter 
 by Spirit of Wine, and afterwards the fa- 
 line by water. He directs Wormwood, 
 Brook-lime, Pellitory, Herb-mercury, Sope- 
 wort, or other plants of the like kind, to 
 be dried quick in a fhady place, then cut 
 fmall, and digefted in frefh parcels of reCti- 
 fied fpirit, till the menftruum ceafes to ex- 
 tract any colour. The plant thus freed 
 from its Oil and Refin, is to be gently ex- 
 liccated and boiled in water, the deception 
 filtered, evaporated to a due confiftence, and 
 fet by in a cool place to cryftallize. The 
 cryftals, he fays, are found upon examina- 
 tion to be of the nitrous kind. 
 
 Spieffius on the other hand (in the fecond 
 continuation of the Mifcellanea Berolinenfia ) 
 
 feeks for the effential Salt in the fpirituous 
 tinCture. Wormwood, Carduus benedic- 
 tus, or other like plants, gently dried in the 
 ftiade, are digefted in Spirit of Wine, with a 
 foft heat, till the liquor is tinged green, 
 the tincture put into a glafs cucurbit, and 
 diftilled with the heat of a water-bath, till 
 fo much of the fpirit is coftie over, that the 
 reftduum may be of the confiftence of honey. 
 The whole being now fuffered to remain 
 unmoved till grown perfectly cold, he 
 finds beautiful pyramidal cryftals ftiot from 
 the Tides of the cucurbit towards its cen- 
 ter. 
 
 The laft mentioned author relates like- 
 wife that having made an effence (that is a 
 faturated tinCture) of Elecampane roots with 
 Spirit of Wine, and kept it unmoved for a 
 year, he found a great number of cryftals 
 fhot from the bottom upwards of the thick- 
 nefs ot a quill, and about an inch long. He 
 fays the cryftals obtained by this method are 
 of the nitrous kind, but of a more fubtile 
 
 tafte 
 
2 So Vegetables « general. 
 
 Essential It may be proper toxibferve, that though juicy faline vegetables, whether of 
 Salts, the acid or the fweet kind, give out their faline matter uninjured upon expref- 
 fion ’ y et t ^ ere are many, particularly aromatic herbs and flowers, whofe juices 
 retain nothing of their peculiar fmeli or tafte, and whofe flavour is abfolutely 
 deftroyed by the atftion of the prefs. Squeeze betwixt the fingers a Violet or 
 a Jafmin flower, and all their fragrance is in an inftant loft. 
 
 -Principles. Thus we have feen, that the medicinal and other intrinfic powers of vege- 
 tative lin ta bl es reflde in a few fubftances, which chemiftry, by the moft obvious and 
 ciplesmuftra-fimple of her operations, extra&s, feparates, purifies, and preferves, unaltered 
 ted. in their quality, but greatly increafed in adivity by the rejection of the parts 
 
 which are unadive : That fome of thefe fubftances, as thofe in which bitter- 
 nefs and aftringency conlift, are diflolved by boiling water, and left, upon 
 evaporating the liquid, concentrated into an extrad, whilft that matter on the 
 other hand, in which odours are lodged, exhales along with the water, and 
 may often be colleded in the form of an extremely adive Oil : That hence, 
 when bitter plants, for inftance, are accompanied with an ill fmeli, we can 
 procure in the extrad, the fimple bitternefs diverted of that offenfive part ; 
 and that in like manner, when fragrant fubftances are accompanied with a bit- 
 ter naufeous tafte, we procure the fimple fragrance concentrated in the Oil: 
 That by redified Spirit ol Wine, we frequently obtain the entire virtue of the 
 plant, both fixed and volatile, combined into one extrad. 
 
 Thefe fubftances we call the native principles of vegetables : Native , becaufe 
 they naturally exift in the fubjed, art doing nothing more than barely to ex- 
 trad them : Principles , not as being fimple bodies, for they are all compounded ; 
 but as it is by thefe that one plant differs from another, and that every plant 
 exerts its fpecific powers ; and as we cannot further refolve them, without to- 
 tally deftroying their peculiar qualities, and converting them into fubftances, 
 as different from any thing that exifted in the original vegetable, as they are 
 from one another. 
 
 Artificial Vegetables diftilled in clofe veflfels by a ftrong fire, yield an acid or an alca- 
 principles. line liquor or both, and an acrimonious, fetid, empyreumatic Oil : In the bot- 
 tom of the retort remains a black coal, which burnt in the open air changes 
 
 into 
 
 tafte than common Nitre, smpreffing only 
 an agreeable coolnefs upon the tongue. 
 
 The two foregoing procefles agree but ill 
 with one another : ' How far they are ade- 
 quate to the purpofes intended by them can- 
 not be determined without further experi- 
 ments. It is certain that Spirit of Wine 
 diftblves the fubtile Oils and the Refins of 
 vegetables, which prove a great impediment 
 to the cryftallization of Salts ; whence it 
 Ihould feem, that the Salt might be after- 
 wards extracted by water from the refiduum, 
 to much better advantage than from the 
 plant at firft. But it is certain alfo, that 
 this menftruum diftblves many of the native 
 
 vegetable Salts themfelves ; and that if the 
 tinsfture is faturated, or duly evaporated, the 
 Salt feparates, leaving the oily and refinous 
 matter diflolved. Thus Manna diftblves to- 
 tally in rectified fpirit, and however foul be- 
 fore, is recovered white as fnow, its impu- 
 rities being left in the menftruum : Thus 
 tindtures ofCeleri, Beet-roots, and other 
 plants of the fweet kind, made in rectified 
 Spirit of Wine, depofite on Handing a Sac- 
 charine Salt ; the fpirit, though it diftblves 
 the faline part by the affiftance of heat, 
 gradually parting with it in the cold, whilft 
 the other matter it had extracted remains 
 diflolved. 
 
28 i 
 
 Vegetable Juices. 
 
 into white allies : From thefe is obtained, by elixation with water, a portion 0fP1uNc1r1.Es. 
 fixed alcaline Salt •, a few vegetables excepted, which infteaa of a fixed alcali in v — 
 the afhes, afford a volatile one in the diftillation. 
 
 Thefe products have no refemblance in tafte, fmell, or any other fenfible 
 property, to the original fubjed : Nor are the Spirits, the Oils, the fixed or 
 the volatile Salts produced from one vegetable, to be diftinguifhed from thofe 
 which are afforded by another. Yet fuch has been the infatuation of the che- 
 mifts, that in examining particular plants, they have hitherto fondly purfued 
 this deftrudive refolution, and afligned, for the natural principles of the plant, 
 thefe artificial produds which had no exiflence in it. 
 
 We ffiall now proceed to examine vegetables fingly, according to the 
 fyftem of native principles here laid down, chufing from the almoft endlefs 
 variety of fubjeds, which the vegetable kingdom affords, fome of the princi- 
 pal that have been employed for medicinal, dietetic or mechanic ufes. Thefe 
 may be ranged in two general divifions ; the juices, which iffue fpontaneoufly, 
 or are extraded or purified by the afiiftance of art ; and plants or their parts in 
 fubftance. 
 
 SECT. II. 
 
 Of Vegetable Juices. 
 
 CLASS I. 
 
 GUMS. 
 
 T H E ftrongeft Gum is that called, from the Tragacanth or Goats-thorn- Gums. 
 tree which produces it, Gum Tragacanth, and corruptly Dragant. The 1 — ... > 
 
 Goats-thorn is a prickly, papilionaceous-flowered tree, growing in the Tragacanth. 
 ifland Candy and other parts of Afia, near Aleppo in Syria, in Cilicia, on the 
 fea-coafts about Marfeilles, &c. In Candy, the gummy juice begins to exude 
 about the latter end of June : Tournefort has given a copper-plate reprefenting 
 its fucceffive protrufion, and the manner of its concretion : It proves more or 
 lefs pure, of a whiter or darker colour, according to the weather after its exu- 
 dation, and the accidental admixture of duft. 
 
 The beft Gum Tragacanth is in white, light, fmooth, tranfparent, vermi- 
 cular tears or ftrise, of a fweetifh tafte, without any fmell. A yellowifn or 
 brownifh colour, though an imperfedion in the drug, is not a mark of its being 
 impure : The very whiteft Gum becomes dark-coloured, barely by being dif- 
 folved in pure diftilled water, and exficcated again by a gentle warmth : Some 
 report, that it fuffers the fame change on being long kept. It dilfolves totally 
 in water : Spirit of Wine extrads only about half a fcruple out of an ounce. 
 
 It gives over nothing in diftillation either to water or to fpirit, both the liquors 
 arifing unchanged. It is difficultly reducible into powder, unlefs it be tho- 
 
 O © roughly 
 
282 Vegetable Juice s. 
 
 G u m s. roughly dried, and the mortar heated ; or in winter, when ftrong frotts have 
 rendered the Gum hard and brittle. 
 
 Gum Tragacanth is made ufe of for fattening down dry fpecimens of plants 
 upon paper, in making artificial flowers, in dying filks, and for the other more 
 curious mechanic purpofes, where a ftrong and a fine Gum is required, whe- 
 ther for conglutinating, ftifiening, or brightening. In medicine, it is employed 
 for giving tenacity to powders, io as to fit them for being made into troches 
 and other like forms : In eledfaries it is improper, as it renders them too flimy 
 upon keeping. Tough cohefive fubftances, as Agaric and Colocynth, are 
 made pulverable by beating them with a mucilage of Gum Tragacanth, and 
 then drying the mafs. With regard to the virtues of this and other Gums, 
 they fatten and thicken acrimonious thin juices, and hence their ufe in fluxes, 
 and in fome kinds of coughs and other diforders of the breaft : In coughs 
 where thick phlegm abounds, they are rather hurtful than beneficial (/). 
 
 CLASS II. 
 
 RESINS. 
 
 Resins. 
 
 Balfams. 
 
 O F the refinous juices of vegetables, there are fome which exude flowly, 
 and after their exudation loon concrete upon the tree into folid tears or 
 mafies, of various figures and magnitudes. Others ifiue more copioufly, re- 
 tain their fluidity longer, and are commonly brought to us in their liquid ftate, 
 under the name of balfams («). Balfams 
 
 (/) Gum Tragacanth . ] This differs from all 
 the othergummy fubftances hitherto known, 
 in giving a thick confiftence to a much 
 larger quantity of water, and being much 
 more difficultly, or rather not at all per- 
 fectly diffoluble. Put into water, it flowly 
 >mbibes a large quantity of the liquid, fwells 
 into a large volume, and forms a foft but 
 not fluid Mucilage. If the quantity of wa- 
 ter is more than the Gum can imbibe, the 
 Mucilage forms an irregular mafs, which 
 does not mingle with the reft of the water 
 on Handing for many days, but unites or 
 difi'olves by flight agitation : The folution 
 has a wheyifh or turbid appearance ; and on 
 Handing for a day or two, the Mucilage 
 fubfides again, the limpid water on the fur- 
 face retaining little of the Gum. 
 
 Gum Arabic, Gum Senegal, and the 
 Gums of the European Plum and Cherry- 
 trees, feem to be but little different from one 
 another : The Senegal is fuppofed to be the 
 ftrongeft, and the Arabic the fineft Gum. 
 Gum Senegal, brought from the ifland of 
 that name on the coaft of Africa, commonly 
 fupplies the place of the Arabic in thefhops, 
 
 and is the fort chiefly employed by the cal- 
 lico-printers, and in other bufineffes where 
 Gums are made ufe of : It is generally in 
 
 larger maflfes than the other, and of a darker 
 yellowiflh or brownilh colour. All thefe 
 are nearly pure Gums : They readily and 
 perfectly diffolve in water into a limpid li- 
 quor, and do not feparate from it upon 
 {landing : On infpiffating the fojutions, the 
 exficcated Gums prove, like Gum Traga- 
 canth treated in the fame manner, conlider- 
 ably darker coloured than at firft. 
 
 It is obfervable that Gum Arabic and 
 Gum Tragacanth are very little difpofed to 
 unite with one another. When difl’olved in 
 water and mixed together, the Gum Tra- 
 gacanth feparates in a much fhorter time 
 than when dilfolved by itfelf; and this whe- 
 ther the folutions be thick, or diluted largely 
 with water. 
 
 (u) Refins .] It is fuppofed, and with great 
 probability, that Balfams and Refins, are no 
 other than vegetable Oils, of the fubtile or 
 the grofs kind, fomewhat altered by the in- 
 timate admixture of a vegetable acid and 
 
 perhaps 
 
Vegetable Juices* 283 
 
 Balfams diffolve, like the folid Refins, in rectified Spirit of Wine, moll: rea- Resins. 
 Jily in fuch as is impregnated with fixed alcaline Salt. They mingle with 
 all effential Oils, though with one more readily than with another. By tritu- 
 ration with Almonds, Piftachio nuts, Hazel nuts, and other like undtuous fa- 
 rinaceous kernels, they become mifcible with water into an emulfion or milky 
 liquor. Yolk of eggs alfo renders them foluble in water; and Sugar ffill 
 more elegantly (x). In diftillation with water they yield, fome a large, and 
 others a ffnall quantity of effential Oil, a folid brittle Refin remaining behind 
 in the fiill. 
 
 T H E mod precious of the Balfams is that commonly called OP O B AL- j 
 S A M, or Balm of Gilead, Opabalfamum , Balfamelaon , Balfamum verum , Album, Opo balsam. 
 ABgyptiacum , Judaicum , Syriacum , Gileadenfe , e Mecca , &c. This is the pro- 
 duce of certain trees, which grew formerly in the valley of Jericho, but after 
 theconqueft of the Holy Land by the Turks, were removed to Grand Cairo, 
 where the Balfam plantation is faid to be now guarded by Janiffaries, and the 
 refinous juice colledted for the Sultan only. 
 
 We are not to imagine, that what is fold by the druggifts under the name of 
 this balfam, at no very great price, is the true Egyptian fort: It is either the 
 native juice of another kind of tree, or what is more probable, a compofition 
 of Balfam of Copaiba with diftilled Oils, &c. Hence we meet with Opobal- 
 famsvery different from one another, or agreeing only in external appearance. 
 
 The 
 
 perhaps an over-proportion of earthy mat- 
 ter, or deprived of their more volatile and 
 watery parts. 
 
 Some of the chemical writers, particu- 
 larly Mr. Macqueiy imagine mineral Bitu- 
 mens alfo to be of the fame origin ; to be 
 no other than vegetable Refms, fomewhat 
 altered by the admixture of mineral acids in 
 the earth. This opinion, though it appears 
 fpecious from the confiderations brought in 
 fupport of it, is built perhaps upon too 
 flight foundations. 
 
 Mineral Bitumens are very different in 
 their qualities from vegetable Reims ; and 
 in the mineral kingdom we find a fluid Oil, 
 very different from vegetable Oils. The 
 mineral Oil is changed by mineral acids into 
 a fubftance greatly refembling Bitumen ; 
 and the vegetable Oils are changed by the 
 fame acids into fubftances greatly refembling 
 the natural Refins. From Bitumens we 
 gain by diftillation the mineral Oil, and 
 from Refms the vegetable Oil, diftinff in 
 their qualities as at firft. Vegetable Oils 
 and Refins have been treated with all the 
 known mineral acids, but have never yielded 
 any thing ftmilar to the mineral Bitumens. 
 
 Q 
 
 It feems therefore, as if the oily produffs of 
 the two kingdoms were fpecifically and ef- 
 fentially different. The laws of chemical 
 enquiries, at leaft, demand that we do not 
 look upon them any otherwife, till we are 
 able to produce from one a fubftance ftmilar 
 to the other. When this fhall be done, 
 and not before, the prefumptions that na- 
 ture effeffs the fame change in the bowels 
 of the earth, will be of fome weight. 
 
 (x) Balfams, rendered mifcible with water by 
 Sugar, See.] Balfams, like effential Oils, are 
 {till more elegantly diffolved in water by the 
 intervention of Gums and Mucilages ; and 
 the folutions obtained by the means of thefe 
 are likevvife the moft permanent. Gum is 
 the medium employed by nature herfelf for 
 uniting the oily, refinous and balfamic 
 juices of vegetables with the watery ; the 
 medium, which enables water to extraff by 
 infufion, the flavour of aromatic herbs. 
 Gum T ragacanth renders Oils and Balfams- 
 mifcible with water, as well as the more 
 foluble Gums ; but the folutions made by 
 the former are lefs permanent than thole’ 
 made by the latter, 
 o 2 
 
284 Vegetable Juices. 
 
 o pobalsam. The only fpecimen of the genuine Egyptian Baliam that I have ever feen, was 
 
 — 1 one in the Royal Apotheca at Drefden, received by King Auguftus among 
 
 other prefents, from the Grand Signior himfelr. An Arabian Balfam, left in 
 our own repofitory by my predecelTor Gundelfheim, who had probably pro- 
 cured it in Arabia or at Conftantinople, where he travelled with Tournefort, 
 comes the neareft to the above. 
 
 The true Balfam is of a pale yellowifh colour, clear and tranfparent, about 
 the confidence of Venice Turpentine, of a ftrong, penetrating, agreeable, aroma- 
 tic fmell, and a llightly bitteriih pungent tafte : By age it becomes yellower, 
 browner and thicker, lofing by degrees, like effential Oils, fome of its finer 
 and more fubtile parts. To fpread, when dropt into water, all over the fur- 
 face, and to form a fine, thin, rainbow-coloured cuticle, fo tenacious that it 
 may be taken up entire by the point of a needle, were formerly held infallible 
 criteria of the genuine Opobalfam. I have obferved, however, that other Bal- 
 fams, when of a certain degree of confidence, exhibit thefe phenomena equally 
 with the Egyptian (j). 
 
 Yi BALSAM OF TOLU is commonly of a thicker confidence than the 
 
 Bm sam off° re g oin S’ and more of a brownilh colour : When fredi, it has an exceeding 
 T01 u pleaiant fmell, fomewhat refembling that of Citrons. It is faid to be the pro- 
 1 1 duce 
 
 (y) Balfam of Gilead.] This Balfam, ac- 
 cording to Profper Alpinus, is obtained from 
 a fmall Evergreen-tree or Shrub, about the 
 fize of the Privet or Cytifns, with flexible 
 branches and a few leaves, which refemble 
 thofe of Rue or rather of the Lentifk-tree, 
 fet in pairs along a middle rib, with an odd 
 one at the end. The branches are covered 
 with two membranous thin barks, the outer- 
 moft of a red di 111 -brown colour, the inner 
 greenifh ; the woody part is white. The 
 flowers are of a purplifh white colour, in 
 fhape like thofe of Acacia : The fruit is a 
 
 fmall reddifh black berry, containing yellow 
 feeds. 
 
 The wood is faid to be inodorous, the 
 bark fragrant and aromatic, the flowers 
 highly odoriferous ; the berries to be odor- 
 ous, acrid, and bitter, and to yield a yellow 
 liquor of the appearance of honey. The 
 branches and dry berries have been fome- 
 times brought into Europe, and kept in the 
 fhops for medicinal ufe, the former under 
 the name of Xylobalfamum , the latter of 
 Carpobalfamum: Whatever fmell or tafte 
 thefe fubftances may have when frefh, 
 they have little of either as they come 
 to us. 
 
 The precious Balfam exudes in very fmall 
 quantity, from flight inciflons made in the 
 
 bark. According to the author above-men- 
 tioned, it is at firft white, of a very ftrong 
 penetrating fmell, of the Turpentine kind, 
 but fweeter and more fragrant, and of a 
 bitter, acrid, aftringent tafte. It looks in 
 part turbid and thick, like the Oil newly 
 exprefied from Olives : Afterwards it grows 
 extremely thin, limpid and light; its 
 colour changes to a greenilh, then to a 
 Gold yellow, and by long keeping, to 
 that of honey ; it now grows thick like 
 Turpentine, and lofes much of its fra- 
 grance. 
 
 Inferior forts of Balfam are faid to be ob- 
 tained by boiling the branches in water: 
 When the liquor begins to boil, a thin Oil 
 arifes to the furface, and on continuing the 
 cobtion a grofler and thicker one. 
 
 Mr. Geoftroy obferves, that a folution of 
 Balfam of Gilead made in Spirit of Wine, 
 turns milky on being poured into water, 
 but does not depoftte any Precipitate ; and 
 that this mixture is ufed in France as a cof- 
 metic. He fays an equal quantity of Oil of 
 Almonds is previoufly mixed with the Bal- 
 fam ; but this ingredient can be of no 
 ufe, as it totally feparates and falls to the 
 bottom whilft the Balfam diflolves in the 
 fpirit. 
 
U I C E S. 
 
 Vegetable Juices, 285 
 
 duce of New Spain, and to exude in very hot weather, from incifions made in Balsam of 
 the bark of a fmall tree of the Fir kind, called Tolu (z). Tolu. 
 
 y BALSAM OF COPAIBA, Cophahu> Copaif, Campaif, Copalyva , or pjj 
 Gamelo , is obtained from a tree of the fame name, growing in the Brazils, nearg ALSAM 0 f 
 the Rio de Janeiro, in Fernambuco, and St. A r incent’s. It is of a pale yellowifh Copaiba. 
 colour, and thin confidence. It is obfervable, that on mixing this juice with i ? 
 
 the watery Spirit of Sal ammoniac made by Quick-lime, a frothing, or effervef- 
 cence as it is called, enfues, ftronger and of longer continuance than that pro- 
 duced by the famefpirit with any other natural Balfam : By this mark we may 
 diftinguifh the genuine Copaiba from the thin Refin of the Turpentine or Fir- 
 tree which is frequently mixed with, or vended for it (a). This Balfam is at 
 prefent of very common ufe, or mifufe, as a medicine. 
 
 BALSAM OF PERL! is obtained from certain trees of Peru and jy 
 Mexico, differing fomewhat from one another in appearance, and fomewhat Balsam o£ 
 alfo in the quality of their juices. The Balfam-tree defcribed by Pifo, under p ERU 
 the name of Cabureiba , has fmall leaves like thofe of the Myrtle, and a thick 
 afh-coloured bark, covered with a very thin red one : Under this is lodged a 
 
 yellowifh Balfam, that impregnates the whole fubftance of the bark, which by 
 age becomes more and more fragrant. Hernandez defcribes the Mexican Bal- 
 fam-tree, as having leaves like thofe of the Almond, and a thick bark like 
 Cork, from which the Balfam flows upon wounding the outer thin rind. Plu- 
 kenet mentions a tree of the fame kirfd in Virginia, by the name of Arbor Vir- 
 giniana , Pifaminis folio , Baccata , Benzoin um reddens . 
 
 There 
 
 (2) Tolu.] Of the tree which produces 
 this balfam we have no particular defcrip- 
 tion. Linnaeus has given its generical cha- 
 racters, under the name of Tolutfera ; and in 
 thefe it differs greatly from the Firs and 
 Pines, to which it is commonly refembled. 
 The balfam is one of the moft elegant and 
 grateful of the fubftances of this clafs, and 
 does not lofe much of its fragrance when by 
 age it grows confident. It yields very little 
 elTential Oil in diftillation, but impregnates 
 the diftilled water ftrongly with its flavour. 
 By diffolving in this water, in a gentle 
 warmth, a proper quantity of fine Sugar, 
 we obtain a balfamic fyrup greatly fuperior 
 to that made in the common manner with a 
 decoftion of the balfam. I have fometimes 
 obtained from this balfam a faline matter, 
 fimilarto the flowers of Benzoine. 
 
 (a) Copaiba .] It is obfervable alfo of this 
 balfam, that on being diftilled in a retort, 
 it gives over towards the end of the opera- 
 
 tion, an Oil of a fine blue colour, preceded 
 by a limpid, and a yellowifh or Srownifh 
 one. Diftilled with water, it yields a large 
 quantity of a limpid eftential Oil ; from fix- 
 teen ounces I have gained eight. 
 
 The Copaiba-tree is one of the large 
 foreft trees of Brazil and fome other parts 
 of America : Mr. Ray calls it Arbor Balfa- 
 mfera Brazilienfis fruSlu monofpermo. The 
 leaves are roundifh or oval, the flowers pen- 
 tapetalous, the fruit a pod containing a ker- 
 nel like a filberd. The wood is of a deep 
 red colour, and great hardnefs ; and hence 
 is employed in ornamental mechanic works, 
 and is faid to be ufed alfo in dying. The 
 balfam is extracted by making deep incifi- 
 ons in the trunk of the tree, in themiddle of 
 the fummer heats ; if this operation is per- 
 formed too early, no juice exudes, in which 
 cafe the wounds are for a time clofed up. 
 It is faid that twelve pounds of balfam iflue 
 from one tree in a few hours ; but that after 
 once bleeding, it never affords more. 
 
) 
 
 286 Vegetable Juices. 
 
 BALSAMof There are three forts of Balfam of Peru : (r.) A colourlefs or pale yellowifh, 
 Peru, called white, in appearance fomewhat relembling the Opobalfam, and like it 
 
 U. > of a ftrong fmell : This is the native juice, collected and preferved in the fame 
 
 ftate wherein it iffues from the tree. Among us, it is rarely or never met with, 
 (2 .) A dry Balfam, or the foregoing infpifiated by the fun’s heat, in calabafhes 
 or gourd-fhells, in which it is fometimes brought into Europe : This has 
 fomewhat of a reddifh colour, and ftill fmells very agreeably. (3.) The common 
 or black Peruvian Balfam of the fhops. This fort is artificially extracted from 
 the bark, branches and leaves of the tree by cutting them in pieces, and boil- 
 ing them in water: The Balfam is faid to feparate, and arife to the furface, 
 from whence it is taken off (b). A portion of the gummy or other matter of 
 the plant which the water extracts, is retained by the Balfam, and falls to the 
 bottom upon difiolving it in Spirit of Wine. Pomet and others report, that 
 this Balfam is counterfeited or lophifticated with mixtures of expreffed Oils and 
 other lubftances : But happily the Balfam of Peru will not in any degree 
 mingle with thofe Oils; in which refpefl it differs from almoft all the other 
 refinous bodies. 
 
 This Balfam is of a thick confidence, like honey ; of a dark black colour in 
 the mafs, but when fpread thin of a clear reddifh or yellowifh brown, of an 
 agreeable ftrong fmell, fomewhat approaching to that of a mixture of Benzoine 
 and Storax, and of a biicerifh pungent tafte, eafily inflammable, not in the 
 lead mifcible with water, nor rendered turbid or white on being agitated with 
 that fluid. It becomes foluble in water, like the other Balfams, by the media- 
 tion of yolk of eggs or of Sugar : When didblved by the latter, it foon fepa- 
 rates from the water, whilft the former keeps it much longer fufpended. 
 
 In didillation with water, it yields a fmall quantity of a fragrant eflential 
 Oil : Hoffman prepares alfo a grateful fpirit, by drawing over Spirit of Rofes 
 from a mixture of the Balfam with half its weight of Salt of Tartar, divided by 
 moift fand. Diflilled in a retort with an open fire, it affords a Butter like that 
 of Benzoine, and oftentimes a confiderable quantity even of concrete faline 
 flowers, fimilar to thofe procured from that Refin : Different forts of the Bal- 
 fam exhibit fome differences in this operation, but I have never met with one 
 that did not yield both the Butter and Flowers. 
 
 V. TURPENTINES are extracted from different kinds of trees in Europe. 
 
 TuRPEN-The true Terebinth-tree (' T'erebinthus vulgaris C. B.) is found in Spain and the 
 tines, fouthern parts of France, as well as in the ifland Chio and the Indies. It is a 
 v_ — v — middling fized Evergreen-tree, with leaves like thofe of the Bay, bearing purp- 
 Cluan. ]ifh im perfect flowers, and on feparate pedicles, hard unftuous berries like thofe 
 of the Juniper bufh. It is extremely refinous, and unlefs the Refin is dif- 
 
 charged, 
 
 (b) Balfam arifes to the furface .] This is were found to fink both in pure water, and 
 the common account of the preparation of in moderately ftrong vegetable decodfions 
 the Balfam of Peru, nrft publifhed by Clu- and infuftons. In cold water, the drops 
 fius, and copied by mod of the later writers, fall to the bottom entire : In boiling hot 
 It is not however very confiftent with the water, a fmall portion feparates, and forms 
 gravity of this balfam ; for the feveral fpeci- a fine thin pellicle - upon the furface. 
 mens I have examined, inftead of fwimming, 
 
Vegetable Juices, 287 
 
 charged, decays, produces fungous excrefcences, ftvells, burds and dies ;Tur pen- 
 the prevention of which confids wholly in plentiful bleeding both in the trunk tine. 
 and the larger branches. The juice is the Chio or Cyprus Turpentine of the G— -v-*— 
 drops : This fort, as we now and then meet with it (for among us it is very 
 
 rare) is of a quite thick confidence, of a greenifh-white colour, dear and tran- 
 fparent, of fcarcely any tade, and but little fmel!. 
 
 The Larch-tree {Larix folio deciduo conifera J. B.) plentiful in fome places Venice, 
 of France, particularly in Dauphiny, as alfo in Aultria, Tyrol, Italy, Spain, &c. 
 is nolefs refinous than the Terebinth, and no left lubjedt to fweli and burft un- 
 lefs its Refin is evacuated. The young trees yield a thin limpid juice, greatly 
 relembling Balfam of Copaiba, called by the French Bijon ; the older, a yel- 
 lower and thicker one. What is called Venice Turpentine is no other than this 
 juice, brought chiefly from Dauphiny, about the confidence of a thick Syrup 
 or Honey, tranfparent, of a pale yellowiili, a yellow, brownifh, or reddifh- 
 brown colour according to its age, of a bitterifh tafte, and a ftrong, not agree- 
 able fmel 1. What the Venice Turpentine originally was, is now unknown. 
 
 It is fuppofed that Venice was formerly the mart for the Turpentine collected 
 from the Terebinth-tree in the ifland Cyprus ; and that the thinner juice was 
 called Venetian, and fuch as had grown thick Cyprian. At prefentwe receive 
 no Turpentine from Venice or from Cyprus. 
 
 The Strafburgh Turpentine, Terebinthina Argentoratenjls^ fo called from the Strafburgh, 
 place of its produdlion, is extradled from the Silver-fir, the Abies conis furfum 
 fpebl antibus five mas of Cafpar Bauhine(c). The common Turpentine is pre- Common, 
 pared from different forts of the pine. This lad is frequently fophidicated or 
 counterfeited with mixtures of different refinous fubdances, folid and liquid : 
 
 It is quite thick, white, and untranfparent. 
 
 All the Turpentines yield a considerable proportion of Oil. From fixteen Oil of Tur= 
 ounces of Venice Turpentine (the fort principally employed for medicinal pur - PENTINE 2 
 poles) were obtained by didillation with water, four ounces and three drams of 
 effential Oil. The fame quantity diddled without addition, in the heat of a 
 water-bath, gave but two ounces and a half; and from the reflduum, treated 
 with water, only an ounce could be obtained; fo that by this method the yield 
 of Oil is near an ounce lefs than when the Turpentine is diddled diredlly with 
 water. The water remaining in the dill is found to have extracted little or no- 
 thing from the Turpentine : On the contrary, the Turpentine imbibes a part 
 of the water, the reflduum and the Oil amounting together to a full ounce 
 more upon the pound than the quantity of the juice employed. When Tur- Common 
 pentine is diddled or boiled with water till it becomes folid, it appears yel R eBn. 
 lowifh; when the procefs is further continued, of a reddifh- brown colour : In 
 the fird date, it is called boiled Turpentine, in the latter Colophony. 
 
 On diddling fixteen ounces in a retort, with an open fire increafed by de- 
 grees, we obtain fird four ounces of a limpid colourlefs Oil, then two ounces 
 
 and 
 
 (c) Turpentine from the Firs.] Some of the gant refinous juice may be colle&ed from 
 exotic Firs afford Balfams or Refins fupe- the cones of this tree: The leaves alfo 
 rior to thofe obtained from the European emit, when rubbed, a fragrant fmell, and 
 ones, as particularly that called Balm-of- yield with re&ified i'pjrit, an agreeable re- 
 Gilead Fir, which is now naturalised to our finous extract, 
 erwn climate. A large quantity of an ele- 
 
s88 
 
 Vegetable Juices. 
 
 Tur pen- and two drams of a yellowifh one, four ounces and three drams of a thicker 
 tine, yellow Oil, and two ounces one dram of a dark brownifh-red empyreumatic 
 — v — — j Oil of the confidence of Balfam, and commonly didinguifhed by that name. 
 
 The eflfential Oil, called Spirit of Turpentine, is remarkably difficult of fo- 
 lution in Spirit of Wine, though Turpentine itfelf diffolves eafily. One part of 
 the Oil may indeed be diffolved in feven parts of rectified Ipirit, and the folu- 
 tion is in appearance perfect j but on Handing for a little while, the limpid li- 
 quor becomes milky, and by degrees greateft part of the Oil feparates and 
 falls to the bottom, a much larger proportion of the fpirit being requifite to 
 keep it diffolved. 
 
 Ufes of Tur- Turpentine, and the Refin left upon diddling it, are employed in various 
 fFNTiNE. cements, lacquers, varnifhes, in fire-works, &c. As a medicine, it is a hot, 
 ftimulating, detergent, diuretic, pofTeffing at the fame time in a notable de- 
 gree, the healing and corroborating virtues of the other Balfams. The Oil is 
 far more -ftimulating than the Turpentine itfell; and hence, in many cafes 
 where inch a quality would be very injurious, the Refin or Turpentine freed 
 from the hot Oil is given with fafety. Both Turpentine itfelf and its prepara- 
 tions are of frequent ufe all'o externally, in pladers, digedive ointments, and 
 vulnerary Balfams. The Oil is faid to be particularly ferviceable in wounds 
 of the nervous and tendinous parts ; and a folution of it in Spirit of Wine, ap- 
 plied warm, to be one of the mod effectual dyptics in profufe haemorrhages. 
 
 !Ta r. 
 
 k 
 
 Pitch. 
 
 Oleum pini. 
 Acid fpirit. 
 
 Experiments 
 «n Pitch. 
 
 IF the wood of the Turpentine- trees be expofed to the fire, in a veffel every- 
 where clofed except an aperture at the bottom, as for example in a retort with 
 the neck placed lowermoft, the refinous juice melts out by the heat and at the 
 fame time contra&s an empyreumatic fmell and tafte : In this Hate it is Tar. 
 
 Tar is prepared indifferent parts of Germany, Norway, Sweden, &c. from 
 the Pine and the Fir-trees, and in lome places from the Larch and the Terebinth. 
 The wood is incloled in a large oven, to the quantity of ten or more loads at 
 a time : This Hands within another oven called the mantle, the fpace betwixt 
 them receiving the fire : From the bottom of the inner oven runs a gutter, by 
 which the Tar is conveyed off in proportion as it melts out from the wood. 
 
 Tar boiled down to drynefs, is the common black Pitch : This part of the 
 procefs is commonly performed in a Hill, in order to fave an effential Oil 
 which arifes in the boiling, and which is called from the name of the tree which 
 Tar is principally prepared from, Oleum pini, and Oleum t<ed<e. This Oil is 
 greatly valued by painters, varnifiiers, &c. on account of its drying quality : 
 It foon thickens of itfelf, almolt to the confidence of a Balfam. Along with 
 the Oil there comes over a watery liquor, which the workmen injudicioufly 
 throw away : It is a good acid fpirit, capable of being applied to fundry ufeful 
 purpofes : I know a perlon in France who has faved by it feveral thouland 
 dollars. 
 
 Pitch is not, as feme have fuppofed, a pure and perfebt Refin : It has not 
 only differed a notable change from the heat employed in its preparation, but 
 likewife participates of the other principles of the wood, of gummy and faline 
 matter, and of a burnt earth. Hence its difpofition to feparate and precipitate 
 when melted with Oils, Fats and Refins, into pladers and ointments : And 
 5 hence 
 
.Vegetable J u i c e s= 289 
 
 hence it is gradually corroded by air and moiffure when employed as a cement Turpen- 
 or defence for wood or other Jubilances, in fhips, land-carriages, ci Herns, ti ne. 
 calks, Ihingle coverings for houfes, &c. Ship-builders' endeavour to improve 
 their Tar and Pitch, fo as to render them more durable by various addi- 
 tions ( d ). 
 
 Two ounces of dry Pitch, treated with rectified Spirit of Wine, ga\ r e but 
 one ounce and half a fcruple of refinous extradl : Half an ounce of an em- 
 pyreumatic Oil leparated during the digeftion, and there remained undiffolyed 
 half an ounce of earthy matter, from which water would exirasff nothing. The 
 fame quantity of the fame Pitch boiled at firft in water, yielded two drams and 
 half a fcruple of gummy extract : From the remainder, neverthelefs, were ob- 
 tained ten drams of fpirituous extract, that is, neaf two drams more than when 
 fpirit was applied at firft, the indifTolubfe part amounting as before to half an 
 ounce. Thediftilled water fmelt and tailed almolt like red herrings : The fpi- 
 rit had no remarkable impregnation. Eight ounces of Pitch diftilled in an 
 open fire, yielded two ounces one dram and a half of an acid fpirit, and two 
 ounces five drams of a fetid Oil, three ounces of a fhining black coal remain- 
 ing in the retort. 
 
 The ufe of Pitch as a medicine, unlefs for external purpofes, is not to be 
 recommended. The Pitch feraped off from beer calks was the Arcanum of a 
 certain midwife againft uterine haemorrhages, and indeed feldom failed to reltrain 
 the flux, but commonly in a few days brought on unfavourable confequences. 
 
 The foot which arifes in the burning of Pitch, is the fubltance commonly Told Lamp-black* 
 underthe name of Lamp-black: In France, thePitch is burnt for this purpofein a 
 kind of furnace made of tiles, fo difpofed as to prevent theefcape of the fmoke 00. 
 
 THE 
 
 ( d) Additions for rendering Tar more dur- 
 able .] An anonymous correfpondent of the 
 Swedlh academy obferves, that the tar- 
 red or pitched boards and Ihingles, with 
 which houfes in many places are covered, 
 are foon damaged by heat and moillure, the 
 fun’s heat melting off the Tar, fo that the 
 wood remains bare. Some have endea- 
 voured to prevent this, by laying on the Tar 
 late in the year, that the winter’s cold 
 might fix it ; an expedient of fome ufe, but 
 very far from being effectual ; for however 
 the Tar may be hardened by the winter, 
 the return of fummer foon makes it foft 
 again. Others have mixed fmith’s cinders 
 with the Tar, which inftead of mendingthe 
 matter makes it worfe, and all ponderous 
 fubftances do the fame. He fays he has 
 never found any addition comparable to 
 Coal-duft [that of Charcoal he feems to 
 mean,] which is to be ftirred into Tar made 
 hot, in fuch quantity as to render it thick : 
 The mixture is to be laid on with wooden 
 trowels, in a hot day. Tar thus prepared, 
 
 he fays, is fixed, never runs, binds and 
 hardens furprizingly from heat and moi- 
 fture, and Ihines better than Oil varnilh. 
 
 {e) Lamp-black .] What is called Lamp- 
 black (originally perhaps the foot collected 
 from lamps) is obtained, in different parts 
 of Germany, Sweden, &c. not from pure 
 'Refin or Pitch, but from the dregs and 
 pieces of bark of the tree feparated in their 
 preparation. For making common Refin, 
 the impure juice collected from incifions' in 
 Pines and Fir-trees, is boiled down with a 
 little water, and {trained whilft hot through 
 a fack : On cooling, the Refin congeajs 
 upon the furface of the water, and is then 
 packed up in barrels j it is diftinguifhed ac- 
 cording to its colour, into white, yellow 
 and brown. The drofs left on {training, is 
 burnt for Lamp-black, in a low oven, from 
 which the frpoke is conveyed by a long paf- 
 fage into a fquare chamber, having an aper- 
 ture in the top, upon which a large fack is 
 fattened : The foot concretes partly in the 
 p fack. 
 
2go Vegetable Juices. 
 
 VI. THE moft fragrant of the folid Refms, and indeed of all the known vege- 
 Solid table fubftances, is ST OR AX or Sty rax, obtained from a tree of the fame 
 
 St or ax. name faid to grow moft plentifully in Syria, Cilicia and Pamphylia. Ame- 
 
 — ' rica likewife produces Storax-trees, but not that particular fpecies which affords 
 the officinal Refin. The true Storax-tree has leaves like thofe of the Quince* 
 and hence is named by Cafpar Bauhine and'Tournefort Styrax folio mali cotonei : 
 Its flowers are white, in fhape fomewhat like a funnel, divided into feveral feg.~ 
 ments about the edges : The fruit is about the flze of a Hazel-nut, 
 
 The fine Storax, called red Storax or Storax in the tear, is the pure native- 
 
 juice, flowing from incifions made in the trunk of the tree. This is very rarely 
 
 to be met with among us The common Storax is luppofed to be in part an 
 
 artificial compofition, mixed with a confiderable portion of the genuine Re- 
 fin (/); Pomet goes lb far as to fay, that he knew the way of making it. 
 This fort was formerly brought to us inclofed in reeds or canes, whence its- 
 name Styrax calamita : At prefent we meet with it in large cakes or loaves, of. 
 a reddilb brown colour, foftiffi and as it were unCtuous to the touch, yet brittle 
 and friable, intermixed with a notable quantity of faw-duft, of an extremely, 
 pleafant fweet fmell. 
 
 Out of an ounce of common Storax, rectified Spirit of Wine diffolved 
 fix drams: From the refiduum, water extracted half a dram of gummy mat- 
 ter : The reft was almoft mere faw-duft. Another ounce of the fame Storax 
 treated with water at firft, gave two drams of extract; after which, it yielded 
 with fpirit four drams of Refin, the faw-duft remaining as before. 
 
 Pure fpirit elevates in diftillation very little of the fmell of the Storax : The- 
 diftilled water is notably impregnated with its fine flavour, but no feparable. 
 
 Oil 
 
 lack, which- is occafionally removed, and' 
 partly in the chamber and canal, from which 
 it is fwept out. 
 
 Lamp-black is more oily or refinous than 
 the common wood loot : It gives out more 
 to fpirit and lefs to water by infufion, and 
 yields a larger quantity of Oil on diftilla- 
 tion. Mixed with boiled Oil, and a little 
 boiled Turpentine, it forms the black com- 
 pofition ufed as ink in printing. 
 
 (y ) Common Storax.] Of the production 
 of this concrete, we have no fatisfadlory ac- 
 count . . . That it is not an artificial com- 
 pofition, may be judged from hence ; that 
 notwithftanding its large admixture of faw- 
 duft, it is more fragrant than the pure Sfo- 
 rax in the tear, and its fragrance is exaCtly 
 of the fame kind. Some refinous bodies 
 indeed dilcover a greater degree both of 
 fmell and tafte, when diluted with other fub- 
 ftances of themfelves inodorous and infipid, 
 than in their pure ftate ; But the pure Refin 
 extracted from common Storax by Spirit of 
 
 Wine, is ftill more fragrant than the Storax 
 itfelf, and than the Refin prepared by the 1 
 fame means from Storax in the tear. 
 
 It feems probable, that the pure Storax 
 is the juice which concretes upon the tree, 
 and which has loft in the drying, its more 
 fubtile odoriferous parts ; and that the com- 
 mon Storax is the juice received imme- 
 diately in veflels, and mixed with faw-duft' 
 enough to thicken it; the fhops requiring 
 under the name of Storax a folid or con- 
 fident mafs, and evaporation being found to 
 diffipate its fragrance. At leaft I cannot 
 conceive for what other purpofe the woody 
 matter could be added ; for it is too eafily 
 diftinguifhable to have been intended as an 
 impofition. 
 
 The Storax-tree is faid to grow fponta- 
 neoufiy, not only in the eaftern countries, 
 but in Italy; whether it yields any Refin 
 there we have no account. It lcareely 
 bears the winters of our climate without; 
 fhelterc 
 
Vegetable Juices. 291 
 
 Oil is obtained. To. determine this la ft point more fully, I di failed eight Solid 
 ounces of Storax with fixteen ounces of water in a glafs retort : No appearance Storax. 
 of Oil could be perceived till the water was almoftail drawn off, and the re- u 
 maining Storax begun to grow dry and fcorched : Then arofe a fine fubtile 
 Oil, weighing two fcruples, together with nine drams of an empyreumatic li- 
 quor: Prefentiy fucceeded two drams and a fcruple of thick butyracpous Oil, 
 and afterwards two ounces one dram of an empyreumatic Oil, which had no- 
 thing of the fmell of the Storax, along with five drams of an acid fpiri't : The 
 refiduum weighed two ounces and feven drams. The butyraceous Oil being 
 wafned with warm water, and the water fet by in a cold place, a fmall portion 
 of faline matter feparated, fimilar in appearance to the flowers of Benzoine. 
 
 Though rectified fpirit diftilled from Storax, brings over little or nothing of 
 its fmell •, we may neverthelefs obtain a fpirit pretty itrongly impregnated both 
 with the fmell and tafte of the Storax, by previoufly mixing the Refin with 
 twice its weight of Salt of Tartar, and drawing over a redlified Spirit of Wine 
 from this mixture. The ftrongeft and moil fragrant principle, feparable from 
 Storax, is the fubtile, flightly empyreumatic Oil, which arifes firft in the diftil- 
 lation of it. 
 
 Storax is employed in medicine as a corroborant and refolvent, both inter- 
 nally, and in plafters and ointments : But its principal ufe is in perfumes of 
 various kinds. For the nicer purpofes, it fhould be purified by diflolving it 
 in Spirit of Wine, and gently drawing off the fpirit. Some boil the Storax in 
 Wine, till it becomes foft enough to be preflfed from its impurities through a 
 ftrainer : This method is lefs eligible than the other, as a part of the Storax is 
 retained among the faw-duft. Mr. Charas obtained by exprefllon, only three 
 ounces of purified Refin from eight ounces of Storax, whereas by Spirit of 
 Wine, the yield is juft double. 
 
 IN the fhops we meet with a fluid refinous fubftance, called STYRAX VII. 
 LI QUID A. This is faid by fome to be extracted by exprefllon from the Liqjji d 
 bark of the Storax-tree ; by fome from the leaves, or the leaves and bark to- S t o r a x. 
 gether (£), and by others, to be a compofition of Turpentine, Oil, Wine, and 
 
 a little 
 
 (g) Liquid Storax .] The genuine liquid 
 Storax is obtained not from the tree which 
 yields the folid Storax, but from one of a 
 different genus, though ufually called by 
 the fame name. That which yields the 
 folid is diftinguifhed by the epithet Ljhtince- 
 leaved , and that which yields the liquid by 
 that of Maple-leaved Storax. 
 
 The Maple-leaved Storax-tree is a native 
 of Virginia, Mexico, and fome other parts 
 of America, and is eafily naturalized to our 
 own climate. A refinous juice, approach- 
 ing in fragrance to Storax, exudes upon the 
 furface of the leaves, and may be extracted 
 more perfectly by Spirit of Wine : The 
 
 procefs by which the juice is procured abroad 
 has not been tried with the trees raifed here. 
 
 Liquid Storax and liquid Amber are faid 
 to be both obtained from this one tree, th’q 
 firft by boiling the bark or branches in wa- 
 ter, the latter by making incifions in the 
 trunk— — Mr. Petiver gives an account in 
 the Philofophical Transactions, of the pre- 
 paration of liquid Storax, as pradtifed in the 
 ifiand Cobros in the Red-fea, from a tree 
 (which probably is no other than this) 
 called by the Turks and Perfians Rofa- 
 Mallos. The bark is annually cleared off, 
 and boiled in fea-water to the confiftence of 
 Bird-lime: The refinous matter, which 
 p 2 floats 
 
292 Vegetable Juices. 
 
 L 1 q jj 1 D a little folid Storax. This laid account is the mod probable. There is a per- 
 Storax. Ton in our neighbourhood [Berlin] who prepares fome huridred weights every 
 — — > year, and is faid to employ chiefly common Refin. 
 
 Four drams of liquid Storax yielded, with redtified Spirit of Wine, three 
 drams and one fcruple of refinous extract : From the remaining two fcruples. 
 Water took up only a few grains : The diftilled fpirit fmelt a little of the 
 Refin. In diftillation with Water, an eflential Oil arofe, fimilar in flavour to 
 Oil of Turpentine or the Oleum pint. By diftillation in a ftronger fire, inftead 
 of a clear einpyreumatic Oil, what came over v/as almofi: mere pitch. Tbefe 
 experiments are a fufficient proof that the common liquid Storax is an arti- 
 ficial compound. 
 
 Yhymiama. THE CORTEX TFI YMI AM AT I S, called by the ancients Thus 
 t-. - -v— — ' judrforum from its ufe among the Jews in fumigations, is fuppofed to be the 
 bark of the Storax-tree, remaining after the genuine Liquid-ftorax has been 
 extra&ed by exprefiion or boiling. Greateft part, however, of what we now 
 and then meet with under this name in the fhops, is no other than the bark 
 of European trees, artificially impregnated with refinous matter. We may be 
 allured that this is the cafe, where the Thymiama, like that examined by 
 Floffmann, abounds with Refin ( h ). 
 
 VIII. BEN ZO INF, Benzoinum , Benzoe, Belzoe , Afa dulcis, comes the neared: 
 Benzoine. in fragrancy to Storax. The tree which produces Benzoine is a native of the 
 ■w — — > jr a ft Indies, particularly of the iflands Siam and Sumatra. It has foft thin 
 leaves, nearly like thofe of the Citron-tree, and bears a round fruit about the 
 fize of a hazel-nut : It is never permitted to exceed the fixth year, as being 
 
 after 
 
 floats upon the furface, and contains acon- 
 fiderable portion of the lubftance of the 
 bark, is taken off, liquefied again in boil- 
 ing Water, and paffed through a ftrainer. 
 The purer part which paftes through, and 
 the more impure which remains on the 
 ftrainer, are both fent to Mocca, from 
 whence they are fometimes, but very rarely 
 brought to us. The firft is of the con- 
 fiftence of Honey, tenacious like Turpen- 
 tine, of a brownifh colour, an acrid aroma- 
 tic unctuous tafte, and a fmell approaching 
 to that of folid Storax, but fo ftrong as to 
 be difagreeable. The impure fort is full 
 of woody matter, and much weaker in 
 fmell. 
 
 The liquid Amber, or juice which iffues 
 from incifions in the trunk, is at firft of the 
 confiftence of thin Turpentine, but by long 
 keeping grows hard and brittle. It is of a 
 yellow colour inclining to red, of a hot 
 aromatic tafte, and a fragrant fmell, not 
 unlike that of Storax heightened with a 
 
 little Ambergris. It was formerly much 
 ufed as a perfume, but is at prefentfcarcely 
 known in the fhops. 
 
 (b) Hoffmann ’s experiments on the Cortex 
 thymiamatis.~\ This fubftance, common he 
 fays in the German fhops (but fcarcely ever 
 to be feen in ours) has the appearance of a 
 mixture of bark and leaves bruifed and 
 preffed ; and approaches in fmell to liquid 
 Storax. Rectified Spirit of Wine extracted 
 from it a black tindfure, fimilar to a fpiri- 
 tuous folution of Balfam of Peru. The li- 
 quor poured into Water became immedi- 
 ately milky: The fpirit, drawn off by diftil- 
 lation, was of a very fragrant fmell, fo dif- 
 fufive that a fingle dram impregnated with 
 its fragrance fome quarts of Water : The 
 Refin, which remained, had alfo a very 
 pleafant fragrance, and amounted to at 
 leaf!: two ounces from a pound of the 
 bark. 
 
Vegetable Juices. 293 
 
 after this period unfit for yielding Refin ; the inhabitants then cut It down, Benzoine. 
 and fupply it by a young one raifed commonly from the fruit. One tree does L - — 
 not yield above three pounds of Benzoine ( i ). 
 
 The juice exudes, from incifions, in form of a thick white balfam : If col- 
 lected as foon as it has grown fomewhat folid, it proves internally white like 
 almonds, and hence is called Benzoe amygdaloides : If fuffered to lye long ex- 
 pofed to the fun and air, it changes more and more to a brownifh, and at laft 
 to a quite reddifh brown colour. The dealers in this commodity never fell us 
 the fine white Benzoine by itfelf ; but mix it with the inferior and fouler 
 kinds, that one may carry off the other : Hence, in the very befl: Benzoine of 
 the (hops, we meet with pieces of various colours, white, yellowifn white, 
 yellow, brownifh yellow, brown, reddifh brown, and grey, all united into one 
 lump. The dark coloured Benzoine however, if it is free from earthy and 
 woody impurities, and from admixtures of any other Refin, does not appear 
 to be inferior in goodnefs to the white. 
 
 This Refin is moderately hard and brittle ; and yields, on being rubbed or 
 warmed, an extremely agreeable fweet fmell. It totally diffolves in Spirit of 
 Wine into a blood red liquor, leaving only the impurities, which amount 
 commonly to no more than about a fcruple, upon an ounce. To Water, it 
 o-ives out a portion, not of gummy or mucilaginous, but of faline matter, of 
 a peculiar kind, volatile and fublimable in the fire, and which indeed is moil 
 effeClually feparated by dry fublimation, and hence called flowers of Benzoine. Flowers of 
 Such a fubftance is fuppofed to be obtainable from Benzoine alone: I have Benzoins, 
 difcovered however, a like ingredient in folid Storax and in Balfam of Peru; 
 and from the mineral kingdom alfo we may bring Amber in comparifon with it. 
 
 Some prepare the flowers from Benzoine by itfelf, reduced into grofs pow- 
 der ; others mix it, in fine powder, with an equal quantity of wafhed 
 fand. An earthen pot or jar is filled with the matter to one half or one fourth 
 its height, then covered with a conical paper cap, and placed in fand : By 
 
 a gentle heat, the flowers ‘arife into the cap, which, as foon as any confi- 
 derable quantity is judged to be collected, is removed, and fupplied by an- 
 other, and the procefs continued till nothing more v/ill lublime : The re- 
 maining Benzoine, which appears of a blackifh brown colour, may (till be 
 ufed, if no fand has been mixed, in compofltions for yielding an. odoriferous 
 fmoke, and for other like purpofes. This method is not a little trou’olefome, 
 the quantity of flowers obtained by it final], and the flowers themfelves com- 
 monly 
 
 (z) Benzoine.'] The Benzoine-tree (or at 
 Ieaft one which is fuppofed to be the fame 
 with that which affords Benzoine in the 
 Eaft Indies) is plentiful alfo in Virginia and 
 Carolina, and has been thence brought 
 into England, where it grows with vigour 
 in the open ground. The bark and the 
 leaves fmell like Benzoine, and yield with 
 rectified -Spirit a Refin of the fame fmell ; 
 but no Refin has been obferved to iffue 
 from it naturally in this climate; nor, fo 
 far as we can learn, has any Benzoine been 
 
 collected from it in America ; though 
 Commeline calls it Arbor Virginiana , citrea 
 vel limonii folio , Benzoinum fundens , the Vir- 
 ginian-tree, with leaves like thofe of the 
 Citron or Lemon-tree, yielding Benzoine. 
 In its Bowers and fructification it agrees with 
 the bay, and hence is ranked by Linnaeus 
 as a tree of that genus, under the name of 
 Laurus folks enerviis ovatis utrinque acutis in- 
 tegris annuls , the bay with oval undivided 1 
 leaves, pointed at both ends, not ribbed;, 
 falling off in the winter. 
 
294* Vegetable Juices. 
 
 Benzoine. monly tinged of a yellowifh or even a brown colour from fome of the Oil of 
 ^ — ' the Benzoine arifing with them •, for as the fand grows continually hotter and 
 hotter, it is fcarce poffible to prevent the heat increafing fo far as to elevate a 
 portion of the Oil. 
 
 The belt way is, to moiften the Benzoine, grofsly powdered, with Spirit of 
 Wine •, and then proceed to diftillation, with a very gradual fand heat, in a 
 wide necked glafs retort. The flowers nrife immediately after the fpirit, partly 
 in a concrete laline form, and partly in that of a white butter : The receiver 
 being now changed, and the fire flowly increafed, a fmall portion of brown 
 coloured flowers fublimes, followed firft by a fubtile Oil, afterwards by a 
 brownifh Oil, and at laft by a black, thick, empyreumatic one, together with 
 an acid fpirit. If the flowers and butter be difiblved in diftilled Water over 
 a gentle fire, the folution palfed through a filter and fet in the cold ; the fa- 
 line matter fhoots into cry ttalline concretions, of a fine filver whitenefs ; this 
 Salt, like Tartar, being difficult of folution, and when diffolved in hot Wa- 
 ter, feparating again as the liquor cools : The diflfolution'and filtration fhould 
 be performed as expeditioufly, and the veffel kept as much covered, as poffi- 
 ble, to prevent any confiderable diflipation of the volatile matter. The Salt 
 ftill retains, even after this purification, a portion of Oil ; as appears from its 
 penetrating fmell, and from its burning in the fire. Tire Spirit of Wine, 
 which arifes at firll in the dillillation, is impregnated with a little of the Salt. 
 The Oil which follows the flowers, rediftilled from earthy powders, or with 
 Water, may be ufed as an effential Oil of Benzoine, for it has little or nothing 
 of an empyreumatic taint. From fixteen ounces of Benzoine are obtained two 
 ounces of rough flowers, nine ounces of Oil, and feven fcruples of an acid 
 fpirit : The refiduum weighs two ounces and a half. 
 
 Benzoine and its flowers are employed medicinally for refolving and attenu- 
 ating vifeid juices, particularly in disorders of the breaft : But the principal 
 ufe of this fragrant Refin is in perfumes, and as a cofmetic, for foftening and 
 fmoothing the fkin. For this laft purpofe, die Benzoine is diffolved in Spirit 
 of Wine, with the addition fometimes of Storax : The folution, mixed with 
 Virgins milk. Water, forms a white liquor called Virgins milk which on ftanding, flowly 
 depofites a fine white magiftery. Some add, to the tinfiture of Benzoine, a 
 tinifture or folution of litharge in Vinegar, and thus obtain a Compound virgins- 
 
 milk and magiftery, lefs innocent than thofe from Benzoine alone A fmall 
 
 quantity of the Oil of Benzoine heightens the fmell of perfumes, and corrects 
 rancid unguents and balfams. 
 
 IX. TACAMAHACA is a fragrant Refin colle&ed in America. The tree 
 Tacamahaca which produces it is called by John Bauhine Tacamahaca populo fimilis, fruttu 
 — v'"“— colore posonice y Tacamahaca-tree refembling the poplar, bearing a fruit whole 
 colour is like that of Peony : The wood is named by the Englifh, from the 
 ufe to which it is principally applied. Saddle-wood (&). 
 
 The 
 
 (l) Tacamahaca-tree. ] This tree is ana- early in the fpring, a very fragrant balfam 
 live of the more temperate parts of Ame- or Refin, fimilar in fmell to the Tacama- 
 rica, but bears the winters of our own cli- haca brought from abroad. In its balfa- 
 mate, and yields, in the young buds or mic buds, as in its general appearance, it 
 rudiments of the leaves which come forth has a great refemblance to the poplar. 
 
Vegetable Juices, 295’ 
 
 The Refin which exudes fpontaneoufly from the tree, is greatly fuperior TACAMAHACA ' 
 to that which iflues from wounds. The firft is collefted in gourd-fhells, and ' J " 
 
 proves of a clear femitranfparent yellow colour : This is rarely to be met with. 
 
 The ordinary Tacamahaca confifts of tears of various colours, reddifh, yel- 
 lowifh, grey, brown, blackifii, clear and opake, pure and impure, joined to- 
 gether into one mafs, of a folid confidence, partly refembling Benzoine, inter- 
 mixed with leaves and other vegetable matters. 
 
 This Refin, when in perfe&ion, has an aromatic tafte, and a very pleafant 
 fmell, approaching to that of Lavender or Muflc. It difiolves totally, if pure, 
 m redified Spirit of Wine : Out of an ounce, there remained only about 
 eighteen grains undifiolved ; and thele were wholly an heterogeneous matter, 
 on which Water had no adion. Water, applied at firft, extraded only about 
 feventeen grains from an ounce. In diftillation, neither Water nor fpirit bring 
 over any thing confiderable : this Refin being very tenacious of its flavour. It 
 js ufed chiefly in plafters and fumigations. 
 
 LADANUM or Labdanum is the produce of a fmall Ihrub ; which is Ladanum. 
 
 a fpecies of Cijius or Rock-rofe, growing plentifully in the warmer climates, v ^ 
 
 particularly in Greece, in the ifland Candy, as alfo in Portugal and Spain, 
 called by Tournefort Cijius ladanifera cretica flore purpurea. The fhrub is only 
 two or three feet in height : Its leaves are fomewhat like thole of Sage ; the 
 flowers pentapetalous, of a purple colour variegated with a rofe red. 
 
 The Refin exudes, not from the ftem, but upon the furface of the leaves; 
 
 It was formerly colleded only from the beards of goats who browfed upon the 
 plant, and in this manner a little is ftill procured : Hence the hairs inter- 
 mixed in fome of the mafles of Ladanum, called Ladanum a barbis. The 
 greateft quantities are now colleded in Candy, by drawing over the plant, 
 backwards and forwards, in the calmeft and hotteft weather, a kind of rake 
 with leathern thongs inftead of teeth : The tenacious juice adheres to the 
 thongs, and is afterwards fcraped off with knives. It isTaid that one perfon 
 can thus colled three pounds and two ounces in a day. As the plant grows 
 chiefly upon dry fandy hills near the fea-fhores, w'here there is conftantly a 
 little wind, the Refin can never be procured free from an admixture of-duft : 
 
 The colledors alfo purpofely mix with it a certain fine black fancl, found in 
 the neighbourhood, not diftinguifhable by the eye from the Ladanum itfelf. 
 
 In Spain, a more expeditious method is purfued : The leaves of the fhrub are 
 boiled in Water,, and the Refin, which arifes to the furface, fcummed off; 
 
 The Ladanum thus obtained is one of the worft kinds ; the more fubtile and 
 volatile parts of the juice being diftipated in the boiling. '*• 
 
 ■^srod Ladanum looks like a mafs for making pills, of a blackifh grey or 
 an unfightly black colour : It is untranfparent, eafy to break, free from any 
 vifible impurities, of a bicterifh and aftringent tafte : It readily foftens over 
 the fire, and when laid on burning coals, yields an agreeable fmell. The ad- 
 mixture of fand may be difcovered by its grittinels betwixt the teeth when long 
 ©hewed, but more perfectly by folution. 
 
 From fixteen ounces of Ladanum I obtained, by rectified Spirit o fWine, 
 eleven ounces two drams and two lcruples of Refin : The remainder yielded 
 
 witfca 
 
' 2g6 Vegetable Juices. 
 
 Ladanum. with Water, an ounce of gummy extraft •, three ounces five drams and one 
 ' — ■ — y—'mJ fcruple of indiffoluble matter being left. On treating the fame quantity of 
 Ladanum firft with Water, I had two ounces four fcruples of a gummy or ra- 
 ther gumrny-refinous extrad : The refiduum, treated with fpirit, gave ten 
 ounces two drams two fcruples of pure Refin three ounces and a half of in- 
 difioluble impurities remaining. In diffillation with Water, a very fmall por- 
 tion of an eflential Oil arifes : Spirit of Wine likewife brings over fo much 
 oily matter, as to fmell and tafle ftrongly of the Ladanum, and grow milky 
 upon the admixture of Water. 
 
 This Refin is employed in plaflers and ointments, as a coroborant and dif- 
 cutient, but principally as an ingredient in odoriferous compofitions, and fumi- 
 gations. It feems to be one of thofe drugs which, in all the intentions it has 
 been ufed for, may be fpared without much inconvenience. 
 
 XI. ELEMI is a Refin of Afiatic origin: The plant, which produces it, is 
 E l e m i. not as yet known with certainty. There is alfo an inferior kind, brought 
 U»~v— — v from America which is the only one now to be met with in the fhops : The 
 parent of this fort is called by Ray Arbor Brazilienjis gummi elemi fimile fun - 
 dens, (Ac. a Brazilian-tree, yielding a gum like Elemi, with winged leaves, 
 verticillate flowers, and a fruit about the fize and fhape of an olive. 
 
 The true Elemi comes over in large oblong maflfes or round loaves, gene- 
 rally wrapt up in leaves of the Indian reed. It is of a yellowifh or rather 
 greenifh white colour femitranfparent ; of a foft confidence, betwixt that of 
 Wax and Turpentine, or dry on the outfide and foftifh within : By age, it 
 grows hard and brittle throughout. It has a moderately flrong, not unplea- 
 fant fmell ; refembling that of a mixture of Fennel, Daucus, and Smallage- 
 feeds. It is commonly full of impurities, which are obvious enough to 
 the eye. 
 
 Out of fixteen ounces of the purer mafies, rectified Spirit of Wine difiolves 
 fifteen : Of the remaining ounce, Water takes up only one fcruple. Water 
 applied at firft diftblves, out of the fame quantity two drams and two fcru- 
 ples : From the remainder, fpirit extra&s fourteen ounces of Refin. Both 
 Water and fpirit become ftrongly impregnated with its flavour by diftillation : 
 Along with the Water arifes a very elegant and grateful effential Oil, amount- 
 ing to an ounce from fixteen ounces of the Elemi. 
 
 Neither the Oil, the Spirit, or the Water, have as yet been received in me- 
 dicine ; though I am convinced they are applicable to valuable purpofes •, pro- 
 vided we are on our guard, in the choice of the Elemi, againft the too com- 
 snon fophiftications or counterfeits made with boiled Turpentine and other 
 matters. This Refin has hitherto been employed only in external applica- 
 tions in nervine, vulnerary, and digeftive plafters and balfams. In making 
 thefe kinds of compofitions, we muft be careful to avoid too great a degree 
 of heat in mixing the ingredients ; left the eflential Oil, the moft ufeful part 
 of the Elemi, be loft. 
 
 XII. 
 
 A N I M E. 
 
 .) 
 
 ANIME, Amine , or Cancamum, is obtained from an American-tree, of 
 which we have no very certain account, faid to grow chiefly in New Spain and 
 
 Brazil* 
 
Vegetable Juices. 297 
 
 Brazil. The Refin is brought over in yellowifh white, tranfparent, fomewhat An 1 m e. 
 un£tuous tears, and partly in larger maffes, brittle, of a light pleafant tafte, V — j- v — - J 
 eafily melting in the fire, and burning with an agreeable fmell. 
 
 It diffolves totally in rectified Spirit of Wine, the impurities only being left, 
 which commonly amount to no more than about five grains on an ounce. 
 
 Water extracts about half a dram from an ounce : The deco&don infpiffated 
 leaves an undtuous mafs, which makes the fingers manifedly oily. The fpirit 
 drawn off by diftillation, fmells and fades confiderably of the Anime : The 
 
 didilled water difcovers on its furface fome l’mall portion of an effential Oil. 
 
 This Refin is ufed chiefly in nervine, cephalic and refolvent pladers. It can 
 fcarcely operate any otherwife than as a mere refinous lubftance, and may not 
 improperly be fupplied by cheaper Refins. Created part of what we meet 
 with under this name in the fhops, is indeed no other than common Refin, fla- 
 voured with a little of the effential Oil of a certain umbelliferous plant. 
 
 MASTICH is the produce of a fmall tree, called Lentifk or Leniifcus. XIII. 
 The bark of the tree is unequal, rugged, and of a grey colour, the branches Mastick. 
 tough and flexible, the leaves winged and fet in pairs, and the flowers, which < , — > 
 come forth in clufters, apetalous or imperfedt. The fruit, at fil'd like a red 
 berry, is when ripe a fhining black nut. 
 
 The wood of this tree was formerly of confi'derable edeem in medicine, and 
 has of late years alfo been celebrated for a variety of virtues, particularly that of 
 ftrengthening the nerves, by Joh. Bapt. de Wengh and John de Muralto, in the 
 Ephemerides nature curiojorum. It feerns however to be better fitted for the ufe 
 to which the Turks and others apply it, the making of lances and tooth-picks. 
 
 Such at lead as we meet with in the fhops is entirely inert. Good Madich- 
 wood is faid to be hard and ponderous, externally grey, internally white, and 
 of an adringent tade : The officinal fort is whitifh on the outfide, reddifh 
 within, and oftentimes worm eaten. Pomet relates, that the Mifletoe of the 
 Hazel-tree is frequently fold in France for Madich-wood : This report is the 
 more extraordinary, as the Mifletoe is vadly flenderer than Madich, and as a 
 fpecies of the Madich-tree itfelf grows naturally in that kingdom. 
 
 The common Madich-tree, Lentifcus vulgaris, is found in France, Italy, 
 
 Portugal and Spain ; but this fpecies yields little or no Refin. That which af- 
 fords Madich is the produce of the ifland Chio, and didinguifhed in the cata- 
 logue of the Amderdam garden by the title of Leniifcus vera. ex infula Chio cortice 
 & foliis fufcis. About the beginning of Augud, the inhabitants make incifions 
 with large knives in the bark of the trunk, and in a few days after the juice be- 
 gins to exude. About the end of September, they make frefh incifions in the 
 parts before untouched, and thus colle6t a little more. When the tears have 
 grown dry and hard, they are cleanfed from fand, &c. by fifting, an operation 
 very troublefome to the workmen, as the fine dud of the Madich dicks about 
 iheeyes, fo as fcarceJy to be got off with Oil. 
 
 Two forts of Madich are didinguifhed in trade, choice Madich, or Madich 
 in grains, and a more impure dark-coloured kind, called Madich in forts, or 
 fimply Madich. For pladers and other like purpofes, the purer pieces of this 
 
 Q_q lad 
 
298 Vegetable Juices. 
 
 MASTicH.laft kind are commonly made ufe of-, but fome care is requifite in the choice, 
 common Refin or Frankincenle being often mixed with it. Good Maflich is 
 of a pale yeliowifh colour, in roundifh or fomewhat oblong tears, clear and 
 tranfparent, dry without any undluofity. It has a pleafant light fmell, and in 
 burning yields a fmoke not difagreeabie. In chewing, it impreffes a flight not 
 ungrateful tafte, and becomes foft and tough like Wax : By this mark, fophi- 
 ftications of it with Sandarach are readily diftinguilhed, that Refin proving fri<~ 
 able betwixt the teeth. 
 
 Maflich diflolves almoft totally in re&ified Spirit of Wine : It is pretty An- 
 gular, that during the digeflion a portion feparates, indiffolu'ole in the fpirit, 
 though in appearance reflnous, amounting to about two fcruples upon an 
 ounce of the pure grains. Water far from diflolving Maflich, as fome pre- 
 tend it does, has no adion either on Maflich itfelf or on this reflduum. In 
 diftillation, nothing arifes with fpirit, and nothing conflderable with water. 
 Hoffman, however, has difcovered a method of impregnating redified fpirit 
 by diftillation, both with the fmell and tafle of the Maflich : He mixes the 
 Refin with an equal quantity of Salt of Tartar, then adds the fpirit, and pro- 
 ceeds to diftillation in a glafs body with a very gentle fire. 
 
 Maflich is made an ingredient in various kinds of varnifhes, and employed 
 medicinally as a corroborant and reftringent. It is chewed for fweetening the 
 breath, preferving the teeth, and {Lengthening the gums ; and from this ufe 
 as a mafticatory is fuppofed to have received its name. Large quantities are 
 fent annually from Chio, by way of tribute, to the Grand Signior ; greateft part 
 of which is confumed for thofe purpofes at court. This tribute of Maflich is 
 faid to amount to the value of four or five thoufand ducats: According to 
 Tournefort’s account, it muft confiderably exceed that fum. 
 
 XIV. GUM GUAIACUM, fo called, is a Refin exuding from the Guaiacum- 
 Guaiacum. tree, of which hereafter. It is of a brown colour, partly reddilh, and often 
 v— — ' greenifh, brittle, of a gloffy furface when broke, of a pungent tafte, and when 
 rubbed or heated, of a not difagreeabie fmell: Its fmoke in burning, has 
 fomewhat the fmell of that of wood. Such fhould be chofen as has pieces of 
 the bark adhering, and eafily parts from them by a few quick blows. The 
 maffes which have no bark, efpecially the large ones, are often fophifticated : 
 I received for Gum guaiacum, a whole box of an artificial compofition of Co- 
 lophony and Balfam of Sulphur : This abufe was readily diftinguifhable by the 
 fmell of the compound when laid upon burning coals, and even by its appear- 
 ance upon breaking. 
 
 Out of an ounce of Gum guaiacum, rectified Spirit of Wine diffolves fix 
 drams and two fcruples : Of the remainder, water takes up only ten grains, 
 all the reft being an indiffoluble earth. Water applied at firft, extracts four 
 fcruples out of an ounce : Of the reflduum, fpirit diffolves four drams and two 
 fcruples. In diftillation, it gives over a little both to water and to fpirit, 1b 
 little as to be altogether inconfiderable. 
 
 Its virtues are the fame with thofe of the wood. It is ufed pretty frequently 
 in England, very rarely in Germany, the pure Refin artificially extradled from 
 
 5 the. 
 
Vegetable J u i c e .s. 299 
 
 the wood by means of Spirit of Wine, advantageoufly and elegantly fupplying Guaiacum. 
 its place (/). 
 
 CLASS 
 
 (/) Additional articles .] COPAL. This 
 Refin is brought in irregular lumps from 
 New Spain, where it is faid to be obtained 
 from different forts of large trees, of which 
 eight are defcribed by Hernandez. Some 
 pieces are whitifh, femitranfparent, friable, 
 not unlike the finer kinds of common Refirs 
 grofsly powdered and forced together into a 
 mafs. Others are more tranfparent and lefs 
 friable, and of a yellowilh or brown co- 
 lour. It has a more agreeable fmell than 
 Frankincenfe, to which fome have refembled 
 it, and does not melt fo thin or burn away 
 fo faff upon a red-hot iron. It does not 
 foften in the mouth, on being chewed, like 
 Anime with which it has been confounded 
 by others. From thefe and other refinous 
 bodies it differs more remarkably, in its be- 
 ing exceeding difficultly diffoluble in recti- 
 fied Spirit of Wine. 
 
 Solutions of Copal have been greatly 
 efteemed as varnifhes, and the method of 
 making the folution kept a fecret in parti- 
 cular hands : Juncker informs us, that it 
 readily fucceeds, if Spirit of Sal ammoniac, 
 mixed with a due proportion of Oil of Spike 
 or Oil of Turpentine, is ufed for the men- 
 ftruum. 
 
 DRAGbNS BLOOD. 
 
 TJ Ragons Blood, Sanguis draconis , is a 
 
 Refin of a red colour, brought from 
 the Eaft-Indies. There are two forts of 
 it ; one in fmall oval drops or tears, of a 
 fine deep red, which is heightened into a 
 crimfon on grinding them into powder ; the 
 other is in larger maffes, apparently com- 
 pofed of tears : Of thefe, fome are of a pale 
 dull red, others of a deep one not at all in- 
 ferior to the drop fort. 
 
 The drops and the lumps are fuppofed to 
 be the produce of two different trees. The 
 lump fort is faid to exude from the trunks 
 of certain palms growing in the Madera 
 and Canary iflands ; the drop to be artifi- 
 cially extracted from the fruit of a tree. 
 According to Kaempfer, the fruit is laid 
 upon a kind of hurdle, over a large veffel 
 half full of water : The whole being lightly 
 eovered, the water is made to boil, when 
 
 Q. 
 
 the fruit being foftened by the fleam, a red 
 juice, which was not difcoverable in it be- 
 fore, appears upon the furface : This is 
 fcraped off upon flag leaves, and expofed to 
 the air to dry. The fame author informs 
 us that fome of the preparers of this com- 
 modity boil the fruit in water, till all the 
 colouring particles are extracted or melted 
 out ; after which, the aqueous fluid is eva- 
 porated till the remainder begins to thicken, 
 when it is further exficcated upon flag 
 leaves as before. 
 
 This drug has been fometimes counter- 
 feited with artificial compofitions, coloured 
 with the true Dragons Blood or Brazil- 
 wood : Thefe are diftinguifhed by their 
 either diffolving in water like Gums, or 
 crackling, and not burning in the fire. 
 
 The genuine Dragons Blood is not aCled 
 upon by water, or at mod communicates to 
 it only a flight yellowifh tinge : Laid on a 
 red-hot Iron, it readily melts, catches flame, 
 and emits an acid fume approaching to that 
 of Benzoine. It diffolves, but not perfectly, 
 in rectified Spirit of Wine, and tinges a large 
 quantity of the menftruum of an elegant 
 blood-red colour : It diffolves readily in 
 Oils, and tinges them of a pretty deep red, 
 but fomewhat lefs beautiful than the colour 
 of the fpirituous tinCture, and confiderably 
 lefs fo than that which Anchufa imparts to 
 
 Oil. 
 
 The fpirituous tinCture ftains cold Marble 
 of a bright flefh colour ; to warm Marble, 
 it gives a deeper red in proportion to the de- 
 gree of heat. Mr. du Fay obferves, that by 
 this one ingredient, with the addition of a 
 little Pitch for the darker colours, all the 
 various Ihades of red may be obtained from 
 the lighted: to the deepeff ; that it does not 
 fink near fo far into cold as into hot Marble, 
 and that the not finking is rather an ad- 
 vantage than an imperfeClion, as the co- 
 lours which fink muff alfo fpread, fo as to 
 render the drawing of fine defigns impracti- 
 cable ; that the belt way of obtaining beau- 
 tiful reds from Dragons Blood is, to put 
 the powdered Refin into Spirit of Wine over 
 the fire, and apply on the Marble with a pen- 
 cil, the finer part of the folution which rifes 
 q 2 up 
 
3 °° 
 
 
 V E G 
 
 table Juices. 
 
 CLASS III. 
 
 GUMMY-RESINS. 
 
 Gummy-^HOUGH fome of the refinous juices of the foregoing clafs contain a 
 Resins. j[_ portion of gummy matter, they are noton that account to be ranked 
 v— ; among Gummy-refins. By Gummy-refins are underftood thofe only in which 
 the quantity of Gum is fo large, as to render the Refin foluble along with it in 
 water by the afliftance of trituration, into a feemingly uniform but untranfpa- 
 rent liquor. Thefe folutions are only temporary : Upon Handing, greateft part 
 of the Refin fubfldes again, the liquor becoming clear, and retaining no more 
 than it would have taken up by infufion or digeftion. The folutions of the 
 common Gummy-refins obtained by triture, appear of a milky whitenefs, ex- 
 cepting that of the high-coloured Gummy-relin Gamboge, which communi- 
 cates in fome degree its high colour to the liquor. 
 
 X. GAMBOGE is brought from the Eaft-Indies, in large cakes and rolls. 
 
 Gamboge, folid and brittle, of a fmooth furface, perfedlly opake, free from any vifible im- 
 U— -v — J purities, of a deep reddifh-yellow colour, equal and uniform throughout its 
 whole fubflance. It ftains the moift hands yellow, and makes a beautiful yel- 
 low Pigment for the painter (m). 
 
 This Gummy-relin has received a variety of names : From the province 
 which affords the largeft quantities, it is called Gambogia , Cambodia , Cambugium •, 
 from the virtues afcribed to it againft the gout, Gummi ad podagram, Gummi 
 gutta ; by a corruption of thefe names, Gummi ghitta, Gummi gotta, Gutta gam- 
 ba , Gamandra , Gemou , Cattagemu , Catagauma , &c. from its Gold colour, Chry- 
 fopus-, from its purgative quality, Succus laxativus, Succus indicus purgans. Scam- 
 monium orient ale , &c. It is fuppofed by fome to be the produce of certain 
 trees, defcribed and figured in the Hortus malabaricus by the name of Coddam- 
 pulli ; by others with greater probability, to be obtained from a fhrubby plant, 
 of the Efula or 'Tithymalus kind : The qualities of Gamboge itfelf fhew it to be 
 more allied to the juices of thefe kinds of plants, than to thofeof trees. Thus 
 much is certain, that it is wholly a natural juice, not as fome have pretended, 
 Gcammony or other like fubfcances, coloured with Rhubarb, Turmeric, or 
 Celandine. 
 
 Gamboge when firft chewed, difcovers little or no tafte, but foon after im- 
 preffes a pungent acrimony and heat, and occafions a drynefs in the mouth. 
 It eafily melts over the fire, and takes fame from a candle : It burns, not as 
 fome report, with a blue, but with a white flame, and leaves not a black, but 
 
 a grey 
 
 up about the Tides of the veflel, adding frefh my-refin gives alfo a beautiful and durable 
 fpirit in proportion to the evaporation, till Citronyyellow flain to Marble, whether 
 the Dragons Blood yields no more tinddure. rubbed in fubftance on the hot ftone, or 
 
 This Refin in fubldance, has no fniell or applied like Dragons Blood in the form of a 
 Safte : When diffolved, it difcovers a flight fpirituous tindfure When applied on cold 
 degree of pungency* Marble, the ftone is afterwards to be heat- 
 
 ed, to make the colour penetrate. 
 
 (m) Gamboge— yellow Pigment.] This Gum- 
 
Vegetable Juices. 301 
 
 a grey alh. Its refinousand gummy matter are fo intimately blended together, Gamboge- 
 that both water and fpirit, applied feparately, diffolve greateft part of both : ^ ^ 
 
 Water acuated with fixed alcaline Salts in moderate proportion diffolves nearly 
 the whole. Out of fixteen ounces, re&ified Spirit of Wine takes up fourteen ; 
 and water out of the fame quantity, takes up thirteen ounces. The two 
 ounces left by fpirit, give out one to water; and the three ounces left by water, 
 give out two to fpirit, the indifloluble matter amounting in both cafes to one 
 ounce. This concrete appears therefore to contain more Refin than Gum. 
 
 Gamboge is a ftrong purgative, and oftentimes proves alfo emetic : It is 
 ufed chiefly as an ingredient in cathartic powders and pills for hydropic cafes, 
 in dofes of a few grains. The tinCture or folution in Spirit of Wine purges 
 more violently than the Gamboge in fubftance, efpecially if infpiflfated to the 
 confiftence of an extraCt : The watery extradl is confiderably milder ; and that 
 made by water impregnated with fixt Alcali ftill more fo. An extract made 
 with alcalized water from the matter left undiflolved by Spirit of Wine, ha3 
 little or no purgative virtue, but operates powerfully by urine. The orientals 
 are faid to prepare an ufeful extract with ftrong Vinegar. 
 
 Sundry additions have been made ufe of for correcting or abating the vio- 
 lence of this medicine, as mineral Acids, Alcalies, effential Oils, Stomachics, 
 
 Spices, neutral Salts, But it feems more prudent to refrain from thele 
 
 kinds of draftic medicines altogether, than to endeavour to mitigate them by 
 correctors. Mr. Boulduc has given in the French Memoirs, a pretty Angular 
 correction of Gamboge • He direCts the powdered Gummy-refin to be tied in 
 a linen-cloth, inclofed in a loaf of bread hot from the oven, and kept warm 
 for twenty four hours, then powdered again, inclofed in a frefh loaf, and this 
 procefs to be repeated four or five times : By this means, he fays, the Gam- 
 boge lofes its draftic quality and becomes afafe purgative : The crumb of the 
 loaf in which it was firft digefted, is found to be ftrongly impregnated both, 
 with the purgative and emetic virtue of the Gamboge. The activity of the 
 Gamboge is doubtlefs by this treatment confiderably abated; but the fame end 
 may be obtained by a procefs ftill more Ample, ftrong coCtion in water. 
 
 THE ftalks of the common Spurges bleed, on being wounded, a milky 
 juice, in tafte acrimonious and burning. The EU P El GR B I U M plant je 
 (fuppofed to be fo called from its firft difcoverer Euphorbus, phyfician to 
 Juba, and brother to Antonius Mufa) is nearly allied to the Spurges, in the 
 flowers, the fruit, and the juice: The principal differences are, that the milk 
 of the Euphorbium is more fiery, the ftalks thick, flefhy, and angular, with 
 ffiarp prickles fet along the prominent angles. 
 
 There are many different fpecies of the Euphorbium plant, natives of 
 Africa, and preferved in Europe in the hot-houfes of the curious. Whether 
 the officinal Gummy-refin of that name is extracted from one particular fpe- 
 cies, or from feveral promifcuoufly, is uncertain: It is commonly fuppofed to 
 be the produce, chiefly of that called by Breynius Euphorbium cerei ejfigie-, &c. 
 Euphorbium refembling the Cereus or Torch-thiftle, with thicker ftalks armed 
 with ftrong fpines : What Ray calls the true Euphorbium of the ancients, is 
 the fpecies defcribed in the Hortus malabaricus , there named Schadidacalli , and 
 
 by 
 
Vegetable Juices. 
 
 Eu p h or- by Breynius Euphorbium lndicum , &c. that is, Indian Euphorbium refembling 
 B i um. the Opuntia or prickly Pear, with a triangular jointed ftalk. 
 
 The juice is extracted by wounding the idem in different parts, pieces of 
 fheep-lkin being previoufly tied round near the bottom, to prevent its running 
 ■down upon the ground : The incifions are made with a long handled inftru- 
 ment, that the operator may receive no injury from the cauftic liquor fpurting 
 upon the face, &c. The juice concretes into roundifh, femitranfparent whitifa 
 tears, which for the moft part are internally hollow : Thefe are the Euphor- 
 : bium brought tons. We commonly find bits of the ftalk, prickles, and feeds 
 of the plant intermixed, and not unfrequentiy fmall ftones and fand. The 
 whitiih or pale yellowilh tears are preferred, as being the frefheft ; the browner 
 or darker-coloured they appear, the longer they have been kept. 
 
 Euphorbium is in tafte extremely acrimonious: The flighted: touch burns 
 and corrodes the tongue : Received in fmall quantity into the nofie, it occafions 
 violent fneezing : The utmoft caution is requifite in pulverizing it, to guard 
 the eyes, nofe, and mouth from the pernicious eftedts of the fine duft that 
 
 The acrimony of Euphorbium feems to refide in the more fubtile parts of 
 the Refin, which are extradled wholly by Spirit of Wine, and almoft wholly by 
 water, the Refill and Gum being nearly in equal proportions. An ounce of 
 Euphorbium yielded five drams of fpirituous extradt-, and another ounce gave 
 juft the fame quantity of watery extradt : Both the extradts were like the Eu- 
 phorbium itfelf, fiery and corrofive, the fpirituous moft lo. The three drams 
 left undiffolved by fpirit, gave out two drams to water-, and the three drams 
 left undiffolved by water, gave out two drams to fpirit, the impurities in both 
 cafes amounting to one dram : Both thefe fecond extradts had little tafte, 
 even the fpirituous fcarcely dilcovered any acrimony till long chewed. No- 
 thing arofe in diftillation with either water or fpirit. 
 
 Euphorbium was given internally by the ancients, in very confiderable doles, 
 as a purgative, for evacuating water and black bile. Nolefs than a fcruple, a 
 dram, and even two drams, are faid to have been taken at once j whereas at 
 prefent, a few grains are found to operate violently both upwards and down- 
 wards, to inflame and corrode the ftomac'n and inteftines, and bring on con- 
 vuifions. In fome cafes it may be fafely mixed in very fmall quantity as a 
 ftimulus with other purgatives but by itfelf it is never to be ventured on •, 
 nor are the corredtions of it with Acids, Alcalies, expreffed Oils, Gums, 
 of much importance. The moft effedtual method of corredting it would be to 
 feparate the cauftic matter by digeftion in water or fpirit, and employ only an 
 extradt made from the refiduum by the contrary menftruum . . . The principal 
 ufe of Euphorbium is for external purpofes, particularly in caries of the 
 bones, the Spina ventofa, feirrhous tumours, for taking off warts, as an 
 ingredient in ftimulating applications and blifters, and among the farriers. 
 Some employ a mixture of it with a large proportion of Florence Orris-root, 
 or a decodtion of it in water as a fternutatory ; a pradtice by no means to be 
 approved. 
 
 flies off. 
 
 THE 
 
3°3 
 
 Vegetable Jutces. 
 
 T HE plant which produces SC A M MCN Y is a fpecles of Convolvulus m 
 or Bindweed, with white flowers, oblong triangular leaves, and large thick Scammony 
 roots. It was acknowledged by the ancients as a plant of the Convolvulus 
 kind, but Morifon was the firfl: who gave it that name : He calls it Convolvulus 
 Syriacus & Scammonia Syriaca ; and in this he is followed by Tournefort and 
 later botanifts. It is a native of different parts of Afia ; that which grows in 
 Syria and the neighbourhood of Aleppo affords the belt Scammony ; that of 
 Smyrna and Myffa an inferior kind. The juice is faid to iffue fpontaneouflv 
 from wounds made in the root, and to be exficcated in theffun or other gentle 
 heat : Some fuipeft, that it is extrafted by exprefllon [n). 
 
 The 
 
 ( n ) Scammony . ] The publick is obliged 
 to Dr. Rufiel for an exadl drawing 
 and defcription of the plant which yields 
 Aleppo Scammony, and the manner of col- 
 lecting the juice, taken upon the fpot, and 
 communicated in the medical obfervations 
 and inquiries publifhed by a Society of Phy- 
 ficians in London. 
 
 The plant, he informs us, agrees in its 
 characters of fructification with the Convol- 
 vulus , as defcribed by Linnaeus in his Ge- 
 nera plantarum , except in the number of 
 feeds, which Linnaeus confines to two, 
 whereas there are oftener three, and fome- 
 times four, in the Scammony. The ftalks 
 are round and pliant, about the fize of a 
 fmall goofe-quill, and run out either on the 
 earth, or on (hrubs, or on fuch other fup- 
 port as they meet with, to fifteen or twenty 
 feet or more : From thefe fpring fmaller 
 branches, at unequal diftances, of little lefs 
 extent than the main ftalks. The leaves 
 grow upon the branches irregularly ; they 
 are thin, foft, of a bright green colour, 
 about an inch and three quarters broad in 
 the wideft part, and grow narrower from 
 thence gradually to a point ; the part next 
 the ftalk has on each fide of the pedicle, 
 two femicircular notches or engrailures, one 
 deeper than the other. The flowers grow 
 upon a fiender ereCf Hem, about fix inches 
 long, divided near the top into two fmall 
 pedicles, each fupporting a fingle flower, of 
 a pale yellow colour, of the fhape of a bell 
 with its brim turned outwards, and undi- 
 vided. Thefe flowers begin to be fent off 
 within about two feet from the root, and 
 continue through the whole length of the 
 plant ; their great number and ereCt fitua- 
 tion above the leaves affords an agreeable 
 appearance,. 
 
 The root is generally from three to four 
 feet long, and about as many inches in dia- 
 meter, covered with a pretty thick aflh-co- 
 loured bark. Its inner fubftance is of a 
 v/hite colour, and manifeftly confifts of two 
 parts, a number of ftrong woody fibres run- 
 ning lengthwife, and fmall bundles of veffels 
 which contain a milky liquor, running in 
 the interftices of the others. Upon cutting^, 
 the root tranfverfely, this ftrufture is very 
 vifible, the fap-veflels being eafily diftin- 
 guifhed by their yellow colour and fpongy 
 texture ; in young roots, the open mouths' 
 of thefe veffels are clearly difcernible by the. 
 naked eye. 
 
 This plant grows naturally on all that 
 chain of mountains which extends from 
 Antioch to mount Libanon, and on that 
 part of mount Taurus which is near to 
 Maraafh ; probably it might be found alfo- 
 on mod of the hills in Syria that afford any 
 verdure. It flowers in May ; the peafants 
 colled! the Scammony in the beginning of 
 June : Having cleared away the earth from 
 the upper part of the root, they cut off the 
 top in an oblique direction, about two 
 inches below where the ftalks fpring from 
 it : Under the moft depending part of the 
 flopc they fix a ftiell, or fome other conve- 
 nient receptacle, into which the milky juice 
 gradually flows. In twelve hours, the 
 whole of the juice is drained off, to the 
 quantity of only a very few drams from one 
 root. The juice from feveral roots is put 
 together, and in a little time hardens into 
 Scammony. 
 
 It is the root only that produces this con- 
 crete ; for the ftalks and leaves near the 
 root, even when preffed, afford no figns of 
 a milky juice. At the fuperior extremity of 
 
 this. 
 
3 ° 4 - 
 
 ScAMMONY. 
 
 Vegetable Juices. 
 
 The Aleppo or beft Scarnmony is in fine, fmooth, fomewhat glofly maJTes, 
 of a grey colour, a fpongy texture, not very heavy, eafily friable, of a difa- 
 greeable fmell, and a bitter naufeous tafte : Powdered it appears of a bright 
 grey colour: On the contact of watery moifture, it becomes milky. The 
 
 Smyrna or inferior Scarnmony, the fort which for ibme years pad the ffiops 
 have been chiefly fupplied with, is of a dark blackifh grey or brownifh colour, 
 more impure, more ponderous, of a clofe compact texture, and does not ap- 
 pear fo white when moiftened. Of either fort we fhould examine the internal 
 part of the mafs, particularly of the large ones : I once found a lump of Lead 
 inclofed. 
 
 The Aleppo Scarnmony contains more Refin and lefs Gum than that of 
 Smyrna. An ounce of Smyrna Scarnmony yielded with water juft half an 
 ounce of gummy ext raft : The refiduum yielded with fpirit two drams of 
 
 Refin, leaving two drams of impurities undiffolved. On inverting the proce- 
 dure, and applying rectified fpirit at firft, I obtained from an ounce, two 
 drams and two fcruples of reflnous 'extradft, and from the refiduum half an 
 ounce of Gum, the indifloluble part amounting here to only four fcruples. The 
 watery infuflons, whether made from the Scarnmony at firft, or after fpirit had 
 performed its office, were extremely mucilaginous, >o as to be difficultly re- 
 duced to a dry confidence. Nothing arofe in diftillation with either water or 
 fpirit, except that the diftilled water difcovered a faint kind of fmell. 
 
 Boulduc informs us, in the French Memoirs for the year 1702, that from 
 four ounces of Aleppo Scarnmony he obtained one and a half of watery ex- 
 trad!, and from the refiduum two ounces of lpirituous extradf ; that from the 
 lame quantity, he obtained with Vinegar two ounces and two drams of extradt, 
 and from the refiduum, with redtified fpirit, ten drams ; and that on applying 
 redtified fpirit at firft, he had three ounces of refinous extradt from four of 
 Scarnmony. 
 
 Scarnmony 
 
 Pure Scarnmony is light, fhining when 
 broke, and crumbles with the leaft force on 
 being rubbed betwixt the fingers. If a 
 wetted finger but touches it, it turns imme- 
 diately milky ; and if broke and put into a 
 glafs of water, it foon diilolves into a milky 
 liquor of a greenifh cart; which, though it 
 lets fall a fediment after fome little time, 
 yet ftill retains its milky colour. 
 
 The colour of Scarnmony feems to be 
 no mark of its purity ; for the dodtor fays 
 he has feen it in all the degrees, from al- 
 mcft a jet black to a yellowifh white, and 
 all equally good. But though it differs fo 
 much in colour when in large pieces, yet 
 all good Scarnmony when powxlered, is 
 nearly of the fame brownifh white colour. 
 
 The Scarnmony plant has been railed in 
 England, from feeds procured by the gen- 
 tleman from whom this account is taken ; 
 and found to flourifh in the open ground, 
 with all the marks of vigour. 
 
 the plant, the leaves and ftalks when 
 ftrongly prefled, do emit a very thin milky 
 liquor ; but its quantity is inconfiderable, 
 and according to the beft obfervation that 
 Dr. Ruflel could make, its quality is diffe- 
 rent ; for neither the ftalks, leaves, flowers 
 nor feeds feemed to have any purgative vir- 
 tue. 
 
 Of this entirely pure Scarnmony very 
 little is brought to market, the greateft part 
 of what is to be met with being adulterated, 
 if not by thofe who gather it, by thofe who 
 buy it of them, with wheat flower, allies, or 
 fine fand, and fometimes with fome other 
 ingredient (poffibly the exprefled juice) 
 which makes it very hard and difficult of 
 folution. The notion of its being adulte- 
 rated with the juice of Spurges feems to be 
 a miftake ; for the dodtor informs us that 
 he has always found the purgative quality to 
 be ftrongeft in pure Scarnmony, and weaker 
 in the adulterated forts. 
 
Vegetable Juices. 305 
 
 Scammony is one of the more powerful cathartics. Some have looked Scammony. 
 upon it as being truly virulent, and contrived fundry methods for correcting 
 or rendering it milder: The only correction now in ufe is expofing the pow- 
 dered Scammony to the fumes of burning Sulphur Thus prepared, it is called 
 Diagrydium , (properly Dacrydion , i. e. Lacrymula ) fulphuratum. Neither this.* 
 however, nor the other corrections, by treating it with juices of different plants, 
 moiftening it with Spirit of Vitriol, baking it in a fcooped quince incloled in 
 dough, &'c. are at all neceffary. Scammony itfelf, or its pure Refin in the 
 dofe of fix grains, duly divided and diffolved or rendered foluble in watery li- 
 quors by trituration with Almonds and Sugar, may be given with fafety 
 where ftrong kinds of purgatives are required. Extracts made from Scam- 
 mony with decoCtion of liquorice,, and with water acuated with fixed alcaiine 
 Salt, are greatly commended by Boulduc, particularly the latter, as being the 
 mildeft and beft preparations obtainable from this Gummy-refin. 
 
 ALOES is a bitter juice extracted from the leaves of a plant of the fame Aloes. 
 name. The Aloe plant has very juicy, thick, fiefhy leaves, and liliaceous • > 
 
 flowers : Many different fpecies of it grow fpontaneouily in the Eaft and Weft- 
 Indies, and are cultivated in botanic gardens in Europe. The officinal Aloes 
 is commonly fuppofed to be the infpiftated juice of the leaves : I hold it to be 
 
 rather a true extraCt, or if it is in fome places prepared by infpiffating the juice, 
 yet that this juice is obtained by cutting, bruifing, and preffing the leaves. 
 
 Three forts of Aloes are diftinguifhed in the fhops, by the names of Aloe 
 foccotorina, Juccotrina , or zoccotrina , Aloe bepatica , and Aloe cabaliina. The epithet 
 Soccotrina is taken from the ifland Zocotora, Hepatica , from the liver colour, and 
 Cabaliina , from the ufe of this fpecies being confined to horfes. The Succotrine 
 Aloes is the belt, the Hepaticknext in goodnefs, and the Caballine the worft. 
 
 Forjmerly there was a kind of Aloes called Lucida , fuperior to all the others : 
 
 This was femitranfparent, and doubtlefs prepared from the pure juice ex- 
 tracted without any confiderable preffiure. At prefent we meet with none of 
 this fort, and we muft be contented with the fuccotrine and hepatic. Thefe 
 differ from one another only in degree of purity (o) ■, and even in this refpect 
 
 they 
 
 feculencies arifing to the furface, and the 
 grolfer falling to the bottom. The juices 
 are afterwards infpiffated by the heat of the 
 fun, to the confiftence in which they are 
 brought to us. 
 
 It is probable, that the Socotorine aloes is 
 prepared by the fir ft of thefe proceffes, and 
 the Hepatic and Caballine by the laft; and 
 that after Handing for the time limited, the 
 juice is ftrained through hair-cloths. The 
 impurities obferved upon breaking a lump of 
 Hepatic or Caballine Aloes are hairs and 
 bits of {kins : but thofe of the Socotorine 
 are gravel and (brail ftor.es. 
 
 (o') Aloes , different in purity .] The three 
 forts of Aloes differ not only in degree of 
 purity, but in fmell, and appear to be ob- 
 tained from three different fpecies of the 
 Aloe plant. The bitter juice refides in di- 
 ftinCt veffels fpread through the fubftance of 
 the leaves ; the fiefhy part of the leaf has a 
 glutinous fweetifh tafte, with little or no 
 bitternefs. 
 
 The aloetic juice is faid to be extracted, 
 by plucking the leaves and ftroaking them 
 gently downwards, or by cutting and brui- 
 ting them, and buffering them to Hand for 
 three weeks or longer, when the hitter 
 juice is found to have l'eparated, the lighter 
 
CO < 
 
 c6 Vegetable Juices. 
 
 lqes they are often fo much alike, that it is not eafy to didinguiffi them. For 
 
 **~y~*~j pharmaceutical and medicinal purpofes, it is indifferent whether we take one 
 or the other, the Hepatic being as good as the Succotrine, provided it is not 
 vifibly foul or drofly ; at lead I have never been able to find any real difference 
 betwixt them in quality.' The principal characters of good Aloes are thefe : It 
 mud be glofiy, not very black, but brown •, when chewed, rubbed or cut, of 
 a yellow colour-, compact, but eafy to break-, eafily foluble; of an unpleafant 
 fmell, and an extremely bitter tafte. Such as is black, firm, and hard to 
 break, we may fulpect to be adulterated. 
 
 The gummy and refinous matter in Aloes, are very intimately blended to- 
 gether, infomuch that either watery or fpirituous menflrua applied feparately, 
 tfilfolve greated part of both. Out of fixteen ounces of Aloes, rectified Spirit 
 of Wine diffolved near fifteen ounces : From the refiduum water took up one 
 dram, about an ounce of impurities being left. On inverting the procedure, 
 and applying water at fird, I obtained but thirteen ounces and a half of watery 
 extract, and from the remainder one ounce and a half of refinous : From whence 
 it follows, that Spirit of Wine is the natural mendruum for Aloes, as it dif- 
 folves out of fixteen ounces an ounce and a half more than water does. It ap- 
 pears further, that the common opinion, that water extracts all the gummy 
 part and leaves all the refinous, is erroneous, though on this principle depends 
 the common procefs of waffling Aloes, or preparing from it a watery extract, 
 with a view to wholly feparate the fuppofed hurtful Refill. Whether the 
 watery or fpirituous extracts are bed, can be determined only by experience. 
 I imagine, the difference betwixt them will not be found to be great. Both 
 the extradis and Aloes in fubdance are purgative; and if ufed too freely, are 
 apt to occafion great heat and ebullition of the blood, and difpofe to haemorrhoi- 
 dal complaints. 
 
 Aloes is an ingredient in many officinal compofitions, particularly in the 
 pills. One of the mod common preparations of it is the Aloe lota or depur at o : 
 This is made by digefting or gently boiling good fuccotrine Aloes with a pro- 
 per quantity of water, filtering the folution, and infpiffating it by the heat of a 
 water-bath to the confidence of an extract, or to fuch a thicknefs that it may be 
 fit for making into pills. If this extract (for itis truly fuch) be made, indead 
 of common water, with the expreffed juice of Violet flowers, it is called Aloe 
 violata and with the expreffed juice of Rofe leaves. Aloe rofata. When 
 the Aloe violata is mixed with half its weight of Creme of Tartar, the 
 ‘compound is named Alee violata tartarea. If the Aloe rofata be diffolved in a 
 good quantity of the frefh juices of Roles, Violets, Borage and Buglofs, mixed 
 in equal proportions, and afterwards reduced by evaporation to its former con- 
 fidence, the extract thus prepared, is called Aloe infuccata, and with the addi- 
 ction of one third its weight of Creme of Tartar, Aloe infuccata tartarizata. 
 Aloes extracted with a mixture of diddled Vinegar and Rofe- water, and after- 
 wards infpiffated, is the Cholagogue extradl of Andernacus : Treated in the fame 
 manner with reftified Spirit of Wine, it yields the refinous extrafl called Balfam 
 ef Aloes, If only a moderate quantity of rectified fpirit be ufed for the extrac- 
 tion, the filtered tintdure is called with propriety EJfence of Aloes. Aloes isalfo 
 the bails of th z Elixiria proprietatis, feveral compofitions of which may be ieen in 
 
 diipenfatoriea. 
 
U I C E S. 
 
 Vegetable j 
 
 /*% e*\ /•** 
 / 
 
 difpenfatories. The beft method of making thefe preparations is, to extract a A l o e s. 
 tincture from each of the ingredients feparately, and then mix the three tine- 
 tures together : By this method the elixir wiil turn out thicker, ftronger, and 
 more faturated than when all the ingredients are di gelled in the menflruum to- 
 gether: It is of advantage alfo to employ for the menflruum, not a highly rec- 
 oded but a phlegmatic Spirit, efpecially for the Saffron and Myrrh. 
 
 It is ohlervable thatEflence of Aloes flains the glafs wherein it has been kept 
 for fome time, of a deep red colour, covering it as it were with a coat of a fine 
 tranfparent varnifh, which no other effence does. Mr. Geoffroy of Paris en- 
 deavoured to perfuade me, that the red tincture on the glafies wherein Elixir 
 prpprietatis is kept, proceeded from the Myrrh and not from the Aloes: But 
 
 on trying Effences of Myrrh and Aloes feparately, the Effence of Myrrh never 
 ftained the glafs, whilft that of Aloes always did. 
 
 Some take the watery extraCl of Aloes, add to it a portion of Terra foliata 
 tartari , and digefl the mixture in Spirit of Wine : This preparation is called 
 Elixir pur gans. If fix teen ounces of Aloes, two ounces of Myrrh, and half an 
 ounce of Frankincenfe be pulverized, mixed together, and diflilled in a land 
 heat in a low glafs body, there arifes an Oil called Oleum Aloes purgans. The 
 Angelic and Frankfort pills, of common ufe as laxatives, confifl either of the 
 Aloe vioiata, or of Aloes mixed with a frnall portion of other purgatives 
 Some add a little Scammony, others difi'olve the Aloes in an infufion of Sena. 
 
 Aloes is employed alfo for external purpofes, a-s a balfamic and vulnerary. 
 
 ON wounding the heads or Italics of the Poppy, a milky juice exudes, 
 which exficcated proves a fine kind of OPIUM. In Natolia, Cilicia, Cap- Opium 
 padocia, in the neighbourhood of Cairo, and in feverai other parts- of the Tur- v— . w 
 kiffi dominions. Poppies are cultivated for this ufe in fields, as Corn among us. 
 
 The method of collecting the juice by incifion is deferibed by Ktempfer in his 
 Arnanitates exotica. This procefs, however, is now but rarely pradtifed, the 
 confumption of this drug being too great to be fupplied by thac method of 
 collection. The belt fort of the officinal Opium is the exprefied juice of the 
 heads, or of the heads and the upper part of the {talks infpiffated by a gentle 
 heat : This was formerly called Meconium, in diltinCtion from the true Opium 
 or juice which blues fpontaneoufly. The inferior forts (for we find consider- 
 able differences in the quality of this drug) are laid to be prepared by boiling 
 the plant in water, and evaporating the (trained decoction : But as no kind of 
 our Opium will totally difi’olve in water, the juice is moft probably extracted 
 by expreffion. I have been informed by fome Turks at Genoa and Leghorn, 
 that in fome places the heads, (talks and leaves are committed to the prefs to- 
 gether, and that this juice infpiffated affords a very good Opium (p). 
 
 Opium 
 
 (p) Opium procured by expreffion, &c.J This from incifions made in the heads, as de-> 
 point has not as yet been fully determined, feribed by Kasmpfer. It is certain, that an 
 It is commonly luppofed, that whatever extraCt made by boiling the heads, or the 
 preparations the Turks may make from the heads and {talks in water, is much weaker 
 Poppy for their own ufe, the Opium brought than Opium ; but it appears alfo that ths 
 to us is really the milky juice collected pure milky tears are confiderahly ftronger* 
 
 R r 2 
 
Vegetable Juices. 
 
 Opiu m. Opium is brought not only from Turkey, but from Perfia and theEaft-In- 
 v— v——/ dies, incl ffed in leaves; the two lad forts are more impure than the firft, and 
 greatly inferior in quality. The larged quantities come from Alexandria, 
 Smyrna and Aleppo : Some of the dealers in this commodity didinguifh the 
 
 bed Opium by the name of Opium cabaifcnum, from its coming over in cala- 
 fcaflies or gourd Thells like Aloes and fome of the Balfams. The principal 
 marks of the gocdnefs of Opium are, its difcovering internally no vifible im- 
 purities, its appearing when broke, in fome degree blight, and ot a dark red- 
 cfifh- black colour, approaching to that of Aloes, its being dry, not loft or' 
 unduous, moderately ponderous and compad, inflammable, of an acrid bitter 
 tade, and a faint finell like that of unripe Poppy-heads, without any thing of 
 an empyreumatic flavour, and its communicating to water not a yellow but a 
 reddifh tindure. 
 
 ■ With regard to the chemical hidory of this extraordinary concrete, its com- 
 ponent parts like thofe of other vegetable fubdances, have been generally 
 Aligned from the refult of dedrudive analyfes by fire ; and its truly wonderful, 
 foporific and anodyne virtues, afcribed to principles which naturally have no 
 exidence in it, as volatile Salts, Sulphurs, empyreumatic Oils, &c. The 
 particular matter on which its adonifhing effeds depend, has not hitherto been 
 exhibited in a feparate or perfedly pure date; but that matter, whatever it 
 may be, it is in the power of chemidry to acuate and concentrate, to obtund 
 and to dedroy. 
 
 The principles feparable from Opium are, a Refin, Gum, a minute portion 
 of faline matter, water and earth. The Relin is of two kinds, one more truly 
 refinous, of a folid confidence, in its nature more fixed, and in its operation 
 more flu ggifh ; the other fofter and thinner, more volatile, and of much more 
 fpeedy and powerful adivity. The faline matter is of the acidulous kind, ana- 
 logous to the efifentia! Salts of other vegetables : Its proportion is fo final!, that 
 it is not eafily feparable in its proper form, though it has fometimes happened, 
 that adual crydals have concreted in a watery iolution of Opium. The Refin, 
 the Gum, and the Salt, are very intimately combined together, infomuch that 
 all the three diffoive almod equally in water and in fpirit: It is phobably to 
 
 the faline principle, in this and other vegetables, that this intimacy of union is 
 in great meafure to be afcribed. 
 
 Four ounces of Opium, treated with highly redified Spirit of Wine, yielded 
 three ounces and four fcruples of refinous extrad : The refiduum, dried and 
 
 treated with water, yielded only four fcruples of gummy extrad, five drams and 
 a fcruple of indiffoluble impurities remaining. On taking four ounces more, 
 and applying water at firft, I obtained two ounces five drams and one fcruple 
 of gummy extrad ; and by digefting the refiduum in Spirit of Wine, three 
 drams and one fcruple of refinous extrad, the indiffoluble part amounting 
 here to i’even drams and a fcruple. In diftillation, redified fpirit brought over 
 little or nothing ; but the diltilled water was confiderably impregnated with the 
 particular ill fmeil of the Opium. 
 
 The fubtile foft kintLcf refinous matter difcovers itfelf in great meafure, in 
 the bare watery foiution of Opium, generally arifing to the furface in form of 
 adat,, unduous,. frothy fubftance. This is the ftrongeft and moft adive pare 
 
 of 
 
Vegetable Juices. 309 
 
 of the Opium ; a few grains are Sufficient to kil! a dog, who could bear aO p i u m. 
 whole dram of crude Opium. From a pound of Opium, we rnaycolledt two ~ v — - — ^ 
 
 or three drams of this balfam -like full fiance ; but we are not to imagine that 
 this is the whole quantity which the Opium contains : Befidcs what thus fpon- 
 taneoufly feparates, a part remains combined with the reft of the juice, and 
 probably is the principle, or the diredl feat of the principle, that gives activity 
 to the whole. 
 
 As Opium in fubftance is frequently found to be productive of unfavourable 
 confequences, different methods have been contrived for correcting or render- 
 ing it more univerfally fafe. In this enquiry, every one has proceeded agree- 
 ably to the idea lie had formed of the compofition of Opium, and endeavoured 
 to counteract that principle, in which he imagined its activity to confift : 
 
 Hence the great variety of pretended correctors. Thole who aferibed its 
 power to a volatile alcaline Salt, thought to mitigate it by acids, as Spirit of 
 Vitriol, dulcified Spirit of Vitriol, Citron juice ; whilst others, deducing its 
 operation from an acid, ufed alcalies for the correctors. Some, prefuming it 
 to be of a cold nature, joined to it hot fubftances, as Cinnamon, Pepper, 
 
 Ginger, Euphorbium, c 6c. theie kinds of additions accompany it in the ancient 
 electaries, and as molt eleCfaries formerly received Opium in their compofition, 
 
 Opiatum became a general name for the form itielf. Some, imagining Opium 
 to be impregnated with a narcotic Sulphur, endeavoured to divert it of that 
 offending principle, by cutting it into thin fiices, and gently roafting it rill it 
 begun to Smell agreeably : Others, afraid that this degree of torrefadtion was in- 
 fufficient for the total diffipation of the Sulphur, had recourfe to a ftronger 
 heat, and destroyed the Opium and ail its powers by burning. On what prin- 
 ciple Henbane feeds and other ftupefadtive bodies were joined to Opium, it is 
 hard to guefs. 
 
 For my part, I am perfuaded, that the narcotic matter of Opium is diffufed 
 throughout its whole fubftance; but that it refides moil copioufly, and in the 
 molt eminent degree, in its finer, fubtile, volatile parts •, that theie parts are 
 capable of being highly concentrated and exalted in their power by art-, I know 
 rnyfelf a certain preparation of Opium, by which a whole chamber full of men 
 may be prefently Stupefied, and deprived of their fenfes, and even of their lives 
 alio, without a fingle grain being fwallowed that the narotic matter cannot 
 be feparated in any vifible form, without fome admixture of the other parts, 
 that Opium cannot be totally freed from it, but by a destruction of the Opium, 
 itfelf ; that it operates nearly in the lame manner as the vapour of burning 
 Charcoal, or the fubtile exhalations from fermenting liquors. To diffipate a 
 part of this fubtile principle, and thus render the Opium more mild and inno- 
 cent, I know of no method more effectual than fermentation. 
 
 The Opium for this purpofe, is to be macerated in water without heat, the 
 Scum which arifes on the furface carefully taken off, the liquor decanted from 
 the undiftblved part, palled through a Strainer, fet in a warm but not dole place, 
 with the addition of fo much Sugar as will difpofe it to- ferment, in a veffel co- 
 vered only fo as to keep out duft r By Stirring the whole well together, when it 
 has ceafed to ferment, a freSh fermentation may be excited: I have thus con- 
 tinued die procefs, in England,, for three quarters' of a year together. When a 
 
 little 
 
^io Vegetable Juices. 
 
 Op I lAf. little of the liquor, Tec in a gentle warmth, in aclofefcopt vial, neither burfts 
 w. the glafs, nor difcovers any expanfive force upon drawing the cork, the fer- 
 
 mentation is completed : The liquor is now to be drained or filtered, and eva- 
 porated to the confidence of an extradl. This is one of the bed preparations of 
 Opium, and was greatly ufed in England during my refidence there. It dif- 
 fers from Langelot’s fermentum anodynum in the fubditution of water to Quince 
 juice, and the omidion of Salt of Tartar ; by which variations, the fermenta- 
 tion lucceeds better and continues longer, and the refinous parts are more 
 effectually feparated. If this extradl is required to be dill more mild, it may- 
 be diffolved afrefh in a large quantity of water, and kept for a time ftrongly 
 boiling in a broad open veffel [q). 
 
 As the refolution of Opium is greatly promoted by heat, we mud be cauti- 
 ous in the ufe of diddled waters and fpirits in which Opium is an ingredient : 
 We are particularly to avoid making any didiilation from it when in adtua! 
 fermentation. A certain phyfician greatly commends a compound Opiate fpi- 
 rit as a mod noble and approved anodyne ; and a mixture of Opium with acrid 
 Tindture of Antimony, as a powerful and fafe diuretic : In another piece, 
 
 however, publifhed not long after, thofe and other preparations of Opium are 
 by the fame gentleman condemned. There are various extradts of Opium 
 made with Water, Spirit of Wine, Vinegar, &c. Wedel fays, he makes his 
 extradl with the Lixivium or Water that remains in the preparation of the Terra 
 foliataTartari : I know of no Lixivium remaining in that procefs, the Terra 
 fcliata being obtained, not by crydallization, but by the total evaporation of 
 the liquor : Probably he means a folution of the Terra foliata itfelf. 
 
 I flan 1 1 conclude this article with fome pradtical cautions, in regard to the 
 ufe of Opium, drawn from experience : ( i .) That neither crude Opium, orits 
 refinous extradl fbould be given by themfelves, in pills or other forms : Star- 
 key’s pills are found to anfwer much better than Opium alone. (2.) That the 
 extradl 1 have recommended, be given rather in a liquid than in a dry form, 
 as in the firft it operates more expeditioufly and with greater fafety. (3.) That 
 tindlures or extradts made with redtified fpirit are moll prudently abflained 
 from. (4.) That thofe preparations are to be ufed with great circumfpedlion, 
 which have been made by bare digeftion, or by an imperfedt fermentation. 
 (5.) That a very final! quantity of my fermented extradf, mixed in glyilers, 
 produces excellent effedts in convulfive and painful diforders, particularly in - 
 the nephritic colic. (6.) That Opiates in general, as they are capable, when 
 properly exhibited, of anfwering the mod valuable purposes in medicine, fo on 
 the other hand, when given imprudently, they are apt to be produdlive of dan- 
 gerous confequences where they do not prove diredtly fatal. 
 
 GUM 
 
 {q) CorreSfion of Opium by fermentation .] it probably does) mull for that very real'on 
 Thefe kinds of preparations are grown, a- render its ftrength vague and impolTible to 
 mong us, entirely into diflife, and very be afcertained. It does not appear, that the 
 juftly. It is a point of primary confequence, corredtions of Opium by fermentation or 
 in preparing a medicine of fuch activity as other like procelTes, do any thing more than 
 Opium, that it be always made of equal what may be equally effected by a diminu- 
 and certain ftrength: fermentation, if it tion of the dofe. 
 tealiy weakens the power of the Opium (as 
 
V £ G IE T A B L E JUICES. $Tt 
 
 GUM HE I) ERAS 5s commonly fuppofed to be the produce of the fie VL 
 dcra Arbor ea or Tree- ivy. JLemery fays ex.prefsly, that it exudes from incifions Gum 
 made in the trunk of that plant, and that the peafants col left it therefrom in Hede R.S, 
 Italy, Provence and Languedoc : Pomet affirms, that he Iras collected it him - — v—— «/' 
 
 i'df from the Hedera at Montpelier. This account, however, is fomewhat 
 doubtful. Though I made great enquiry, in my travels, after the parent of 
 this gummy Refin, [ could never procure any fatisfadory information : All I 
 could learn was, that the greatefl quantities came from the furthermoft parts 
 of the kingdom of Naples, and from Sicily : Of the plant which afforded it, 1 
 could hear nothing-, to the botanifts of Italy, it was unknown. 
 
 This gummy Refin is of a bright, t ran fpa rent, recldifh brown colour, 
 deeper than the Hyacinth, and approaching to that of the Gar-net; when re- 
 duced to powder, of a faffron yellow ; of an agreeable aromatic tafle and fmeli. 
 
 Such is the genuine Gum Hederte. In the fhops, we frequently meet with 
 different fophifticated mixtures under this name ; by thefe probably thofe au- 
 thors have been milled, who defcri’oe Gum Hederte as of a blackifh colour, of 
 no l'mell, of an acrid aftringent tafle, too corrofive for any internal ufe, and 
 f lt oniv for external purpofes, fuch as the deftroying of infects. The true 
 Gum Hederae has no corrofivenefs or acrimony, and may be given inwardly 
 with great fafety, as it frequently was by Stahl, Becher, and many others. 
 
 It has an advantage above all the other known gummy Refins, that it does 
 not occafion any heat or ebullition of the blood and proves an excellent and 
 fafe refolvent and corroborant, in a vifcid date of the juices, in cachexies, 
 chlorofes, and menftrual obftrudions. 
 
 An ounce of choice Gum Hederae yielded, with rectified Spirit of Wine, five 
 drams and a half of refinous extrad ; from the refiduum I obtained by Water 
 half a dram of gummy extrad, and two drams of indiffoluble matter. Another 
 ounce, treated fir ft with Water, gave two drams of gummy extrad ; and after- 
 wards, with fpirit, three drams two fcrupies of refinous extrad ; two drams 
 and half a fcruple remaining undiffolved. The diftilled fpirit has a flight tafle 
 of the Hedera ; the diftilled Water is confiderably impregnated both with the 
 tafle and fmeli, and difcovers on its furface a fmall quantity of effential Oil, 
 which is found on tailing to be lefs hot than the other Oils of that clafs. 
 
 SARCOCOLLA is a gummy Refin brought from the Oriental coun- VII. 
 tries : Neither the plant which produces it, nor the place of its produdion, are SARCorcL1 -' u 
 with certainty known. The beft Sarcocolla is in fmall tears, about the fize of 
 peas, of a whiti-fh or pale-yellowifh colour, of a fpongy texture, very brittle 
 or rather crumbly, fomewhat unduous, eafy of folution in Water, of no fmeli 
 or only a flight refinous one, of a bitter tafle intermixed with a fweetnefs like 
 that of liquorice, but upon the whole not very agreeable. The whiter and 
 bitterer, the frefner and better it is, Greatefl part of what we meet with in 
 the fhops is in a powdery form, the friable tears being probably rubbed into 
 powder in the carriage. We fometimes find among it large maffes of a Vermil- 
 lion red, and others of a brownifh colour, compofed evidently of fmaller pieces 
 joined together, with marks on the outfide like the impreflion from a mat. 
 
ABLE 
 
 3^2 
 
 Sabcocoli. a. 
 
 V F, G E T 
 
 Juices. 
 
 Out of an ounce of Sarcocolla, rectified Spirit of Wine diffolved fix drams r 
 Of the remainder. Water took up only two fcruples ; two fcruples and a half 
 being left undiffolved. Water applied at firft: to another ounce, diffolved feven 
 drams and a half : From the remainder, fpirit took up twenty-fix grains ; 
 fcarcely eight grains being left. The gummy parts therefore prevail, in this 
 concrete, above the refinous. In diftillation, neither Water nor Spirit bring 
 
 over any remarkable fmell or tafte The ufe of this gummy Refin is only as 
 
 an ingredient in fome external applications. It has been fuppofed to conglu- 
 tinate wounds, whence its name Sarcocolla or Flefh-glue. 
 
 VIIL ASAFCETIDA, Sylphium , Laferpitium , Devils dung, fo called from its 
 A^rr'ETicA fmell, is obtained from a large umbelliferous plant, defcribed by 
 
 Kaempfer as of the Lovage kind, with leaves like thofe of Peony, and leafy 
 feeds like thofe of Parfnep ; growing in Perfia, particularly in the province 
 Chorafaan about Heraat, and in the province Laar near Congo and Difguun ; 
 not in Media, Libya, Syria or Cyrene, though fome, from an opinion 
 that it was the produce of this la ft country, have called the juice Succus 
 Cyrenaicus. 
 
 The root of the plant refembles a large Parfnep, externally of a black co- 
 lour : On cutting it tranlVerfly, the Afafoetida exudes, in form of a white 
 thick juice like cream, which from expofure to the air becomes yellower and 
 yellower, and at laft of a dark brown colour : It is very apt to run into pu- 
 trefaction, and hence thofe who colled! it, carefully defend it from the fun. The 
 frefii juice has an exceflively ftrong fmell, which grows weaker and weaker 
 upon keeping : A (ingle dram of the frefli fluid juice fmells more than an 
 hundred pounds of the dry Afafetida brought to us : The Perfians are com- 
 monly obliged to hire (hips on purpofe for its carriage, as fcarcely any one 
 will receive it along with other commodities, its flench infecting every thing 
 that comes near it 
 
 The common Afafoetida of the fhops is of a yellowifh or brownifh colour, 
 unctuous and tough, of an acrid or biting tafte, and a ftrong diLgreeable fmell, 
 refembling that of Garlic. From four ounces I obtained, by rectified fpirit, 
 two ounces fix drams and a half of refinous extract ; and afterwards, by Wa- 
 ter, three drams half a fcruple of gummy extract ; about fix drams and a 
 fcruple of earthy matter remaining undiffolved. On applying Water at firft, 
 1 gained, from four ounces, one ounce three fcruples and a half of gummy 
 extract. The fame quantity yielded, with ftrong French Wine, two ounces 
 and a half and fifteen grains; from which about one fifth may be deducted for 
 the foiid matter contained in the Wine. Schroder fays, that Afafoetida may 
 be diffolved over the fire in Water, Vinegar, or Wine; but only a part of it 
 can be diffolved in any of thefe liquors. The fmell of the Afafoetida refides 
 wholly in an effential Oil, which ariles in diftillation both with Water and. 
 ipiric: Four ounces, diftiiled with Water, yielded above a dram of Oft. 
 
 IX, T H E plant which produces A MM ON I AC U M, and the place of its pro- 
 amm.-.e iac-jm du&ion, are unknown. The beft Ammoniacum is compofed of white, whitifh, 
 or yellowifh tears baked together into inaffcs : The internal parts particularly 
 
 i are 
 
Vegetable Juices, 313 
 
 are whitifh : By age it becomes more and more yellow and brown. It eafily Ammoniacum 
 foftens and becomes tough betwixt the fingers. Chewed, it dilcovers a bit- 
 terifh, glutinous, not difagreeable tafte. Its finell approaches to that of a 
 mixture of Opopanax and Galbanum : Some refemble it to that of Caftor, 
 others to that of Coriander-feeds, and others to that of Garlic. 
 
 It diflfolves almoft equally in Water and Spirit. Out of an ounce of choice 
 Ammoniacum, redified Spirit of Wine dififolved fix drams : Water, applied 
 to another ounce, took up fix drams two fcrupies and a half. From the matter 
 left undiffolved by fpirit. Water took up five fcrupies and five grains : From 
 that which Water left undiffolved, redified fpirit extracted a dram ; the in- 
 diffoluble part amounting in the firft cafe to fifteen grains, in the latter only 
 to half a fcruple. In difiillation, Spirit of Wine arifes unchanged : The dif- 
 tilled Water has fomewhat of a fweetifh tafte, and ifnells a little of the Am- 
 moniacum, but gives no Appearance of any effential Oil. 
 
 Ammoniacum is accounted deobftruent ; promotes urine ; and in large 
 doles, opens the belly. It is given particularly in obftrudions of the bread, 
 in cachedic, hydropic, and apopledic cafes, from a fcruple to half a dram : 
 
 It operates more effectually in a liquid form, as that of an emulfion, than in 
 the lolid one of pills; but is moff commodioufly taken in the latter form. It 
 is fometimes diffolved in vinegar : Externally, it refolves hard fwellings, It 
 is purified by diffolving it in Vinegar, Wine, or Water, and {training and in- 
 fpiffating the folution. 
 
 BDELLIUM is another gummy Refin of which we do not know with x. 
 certainty either the plant or the place of its produdion : It is fuppofed to be Bdellium 
 the produce of Africa. Lemery and Pomet have given fiditious figures of the 
 plant, as the latter has done of many others. The beft Bdellium is of a yeL 
 lowifti brown or dark brown colour according to its age, unduous to the 
 touch, brittle but foon foftening and growing tough betwixt the fingers, in 
 fome degree tranfparent, not unlike Myrrh, of a bitterifh tafte, and a mode-^ 
 rately ftrong fmell. It does not eafily take flame, and when let on fire foon 
 goes out: In burning, it fputters a little, on account of its aqueous humidity, 
 but cannot be faid to explode, much lefs to explode like gunpowder, as Tier- 
 mann and Valentini report. 
 
 An ounce of picked Bdellium, treated with Water, gave fix drams two 
 fcrupies of gummy extrad ; and afterwards, with Spirit, two fcrupies of Re- 
 fin ; two fcrupies remaining undiffolved. Another ounce, treated firft with 
 redified fpirit, yielded two drams of refinous extrad ; and afterwards, with 
 Water, five drams two fcrupies of gum •, only one fcruple remaining undif- 
 jolved. The diftilled fpirit has no tafte or fmell of the Bdellium, and the dE 
 ftilled Water very little. 
 
 GALBANUM exudes from an umbelliferous plant with leaves like thofe xi 
 of Anife, growing in the Eaft Indies, but moft plentifully in Syria and Arabia, Galbanum 
 called by Tourneiort Oreofelinum Africanum , Galbaniferum , frutefcens , aniji folio* 
 
 This juice comes over in maffes, compofed of white, yellowifh, brownifh yel- 
 
 S f low, 
 
3*4 Vegetable Juices. 
 
 Galbanum -low, and brown tears, un&uous to the touch, foftening betwixt the fingers, of 
 a bitterifh, fomewhat acrid, difagreeable tafte, and a very ftrong fmell, gene- 
 rally full of bits of ftallcs, leaves, feeds, and other foreign matters. 
 
 ]Lemery relates a pretty remarkable obfervation •, that Galbanum, Sagape- 
 jnum, Bitumen judaicum, and Opopanax, fubftances whole fmell is difagree- 
 able to every body, being tied in feparate parcels, in the quantity of half a 
 pound of each of the three firlt, and a quarter of a pound of the lalt, and kept 
 for fome time in a pocket ; they impregnated the clothes with a ftrong and 
 durable mufk fmell. There are many inftances of a mixture of fetids producing 
 an agreeable fcent ; but I have not found that this mixture is one of them. 
 I have repeated Lemery’s experiment in the fame manner as he defcribes it, 
 but not with the fame event •, and therefore prefume that the fmell proceeded 
 from fome other caufe. 
 
 Galbanum contains more of a refinous than gummy matter: One pound 
 yields with rectified Spirit of Wine, upwards of nine ounces and a half of re- 
 finous extract •, but the gummy extract obtained by Water from the fame 
 quantity amounts only to about three ounces. The Refin is hard, brittle, in- 
 fipid and inodorous : The gummy extract has fomewhat of a naufeous relifii, 
 but could not be diftingu fhed to be a preparation of Galbanum. The whole 
 fmell, flavour and fpecific tafte of this juice refide in an eflential Oil, which 
 arifes in diftillatipn both with Water and Spirit, and gives a ftrong impregna- 
 tion to both : From a pound of Galbanum are obtained, by diftillation with 
 Water, fix drams of actual Oil, befides what is retained by the Water. In this 
 refpedt, Galbanum agrees with Afafoetida, and differs from Ammoniacum. 
 
 The volatility of the a6Uve parts of this juice, renders the common method 
 of purifying it, by folution, colature and evaporation, very injurious to it . 
 The fmell of the Galbanum is diffufed, during the evaporation, over the 
 whole houfe •, and the infpififated matter, whatever menftruum was employed, 
 is found to have loft the diftinguifhing qualities of the original juice. To pre- 
 vent as much as poflible this inconvenience, the iolution fhould be made in a 
 diftilling veffel, and after filtration, inlpiftated in the fame fo long at leaft as 
 the liquor which diftils has any fmell or tafte ; after which, the Galbanum 
 may be reduced to a due confidence by further evaporation in an open veftei, 
 and the Oil which arifes in the diftillation mixed with it. Galbanum may 
 iikewife be purified, fufficiently for inferior purpofes, as plafters, by expofing 
 it in winter to a ftrong froft till it grows hard, and then pulverifing and fifting 
 it: The woody, ftrawy, ftony, and other like matters will be retained in 
 die fieve. 
 
 Galbanum diftilled by a ftrong fire without addition, yields, like other refi- 
 nous bodies, a large portion of empyreumatic Oil, amounting to upwards of 
 eight ounces upon fixteen : It is remarkable of the Oil of Galbanum, that 
 great part of it appears of a blue colour, fometimes of a deep bright blue, 
 Jometimes only of a violet blue. The matter on which the bluenefs depends 
 appears to be either very volatile or very changeable : It foon efcapes or 
 changes in the air, leaving, inftead of the blue, a purple colour. 
 
 O LI B A- 
 
Vegetable Juices. 
 
 3*5 
 
 OLIBANUM, Thus, Frankincenfe, comes chiefly from Arabia : But not- XII. 
 withftanding its early and frequent ufe in fumigations, the plant which pro- Olibanum 
 duces it is as yet unknown. The ancients diftinguifhed various forts of Oliba- 
 num, as i. Olibanum , or Thus mafculum, Mel ax , Melafon, Tejliculatum , or the 
 pureft, yellowifli white, round tears, which were frequently joined two toge- 
 ther. 2. Thus famininum, or the yellower and more impure. 3. Thus mammo - 
 film, or larger oblong roundifh maffes, fomewhat refembling a woman’s breads. 
 
 4 . Thus granulofum, or fmall granules. 5. Thus corticofum , or fuch maffes as 
 have pieces of the bark of the tree adhering. 6. Thus crobaum or Mica t hurts ; 
 i mail fragments, or particles broke off in carriage, &V. 7. Manna thuris , the 
 
 finer duff. 8. Thus indicum , or large maffes, compofed of different coloured 
 tears, white and blackifh, joined together. 
 
 At prefent only two kinds are diftinguifhed : The finer and purer tears are 
 called Olibanum in grains ; the more impure fragments and maffes, common 
 Olibanum, or Olibanum in forts. The beft is of a yellowifli white colour, 
 folid, hard, and brittle : Chewed for a little time, it renders the fpittle white, 
 and impreffes an unpleafant bitterifh tafte : Laid on burning coals, it yields 
 an agreeable fmell. 
 
 Out of an ounce of the pure tears, rectified Spirit of Wine diffolved five 
 drams two fcruples and fix grains : From the remainder, Water took up two 
 drams and five grains. Another ounce gave out to Water at firft three drams 
 and a fcruple ; and afterwards to Spirit, four drams thirty-three grains. The 
 indiffoluble matter, in the firft operation, weighed twelve grains ; in the other 
 fourteen. Both the diftilled Spirit and Water tailed pretty ftrongly of the 
 Olibanum, but no feparable Oil could be obtained — —Olibanum is accounted 
 corroborant, and fuppofed to be particularly ferviceable in diforders of the 
 head, ftomach and breaft. Its principal ufe is in plafters, unguents, &c. and 
 in fumigations. 
 
 OPOPANAX is the juice of an umbelliferous plant called Panax or All- XlII. 
 heal. It has been generally fuppofed to be the produce of the fpecies, called Opopanax 
 by Cafpar Bauhine Panax fphondylii folio five Heraclcum , Hercules’s All heal 
 with leaves like thofe of the Cow-parfnep : But Ray affirms that it proceeds 
 from a different one, the Panax paflmac<e folio , or Parfnep-leaved All-heal of 
 the fame author : This laft is the fpecies, which Dodonasus railed from the 
 feeds found among the officinal Opopanax. The juice exudes from incifions 
 made in the roots and the lower part of the ftalks. The greateft quantities 
 are collected in Syria, Boeotia, Macedonia, at Phocis in Achaia., as alio in Ly- 
 bia and Cyrene. The plant is found likewife in Sicily and Apulia ; but we 
 have no Opopanax from thence. 
 
 Opopanax, as we commonly meet with it, is of a brownifh colour on the 
 outlide, and paler, inclining to yellowifh, within j the darker coloured, the older. 
 
 It is in fome degree foft or unduous, yet eafy to break ; of a bitter tafte, and 
 a ftrong difagreeable fmell. There are fome pure, firm, compad tears : But 
 much the greater part is extremely foul, being blended throughout with bits 
 of wood, ftalks, leaves, &c, It is often fophifticated-, and in Holland, when it is 
 
 S f 2 dortr* 
 
Vegetable Juices. 
 
 dear, counterfeited by artificial compofitions. Such as is black, and very foft 
 and clammy, fhould be reje<5ted. 
 
 An ounce of Opopanax, treated with re&ified Spirit of Wine, gave two 
 drams two fcruples and fix grains of refinous extraift; and afterwards, with 
 water, three drams of Gum ; two drams and a fcruple remaining undiflolved. 
 Another ounce treated firit with water, yielded three drams two fcruples and 
 fix grains of gummy extract ; and afterwards, with rectified fpirit, one dram of 
 Refin, the indififoluble part amounting to three drams and a fcruple. Both the 
 diftiiled water and fpirit are impregnated with the flavouf of the Opopanax, 
 but no a&ual Oil can be feparated, at leaft on diftilling fmall quantities of 
 the juice. 
 
 S AGAPE NUM is a Gummy-refin of unknown extradion, both in re- 
 ,gard to the plant and the place of its growth. When frefh it appears like the 
 other juices, whitifh : By age, it becomes yellowifh, brownifh, dark-coloured. 
 Good Sagapenum looks almoftlike horn-, it is tranfparent, brownifh on the 
 outfide, whitifh within, of a fomewhat acrid tafte, and a ftrong dil’agreeable 
 fmell, like that of a mixture of Galbanum, Opopanax and Bdellium, with a 
 little Afa fcetida. 
 
 An ounce of the purer fort, digefted with redified Spirit of Wine, yielded five 
 drams and fix grains of refinous extrad: The remainder boiled with water in 
 a clofe veffel, fo long as it gave out any thing to the menftruum, yielded five 
 fcruples and eight grains of Gum : one dram and five grains being left undif- 
 folved. Another ounce treated firft with water, gave two drams two fcruples 
 and a half of gummy extrad; and afterwards, with redified fpirit, four drams 
 and one grain of Refin, one dram and fix grains being left. The diftiiled fpi- 
 rit is fenfibly, and the diftiiled water ftrongly, impregnated with the flavour of 
 the Sagapenum : Along with the water arifes a confiderable portion of aduai 
 
 Oil This and the preceding Gummy-refin are employed in medicine, in 
 
 the fame cafes as Ammoniacum. 
 
 MYRRH is another Gummy-refin whofe origin is wholly unknown. It 
 .comes immediately from Alexandria, Smyrna and Aleppo, often in large bales 
 offeveral hundredweights, inclofed in leather. It is hard, dry, glofly, of va- 
 rious colours, yellowifh, reddifb, brown, yellowifh-brown, reddifh- brown, 
 blackifh, intermixed with whitifh fpecks or tears, tranfparent like Agate, or 
 ooake like Pitch, of a peculiar ftrong fmell, and a bitter fomewhat biting tafte. 
 The beft is that which is of a reddifh-brown colour, not verging too much to 
 yeliowifh or blackifh, uniform on the outfide, internally fpecked or ftreaked 
 with white, clear and bright, fomewhat undluous to the touch, but not tenaci- 
 ous fo as to flick to the fingers. 
 
 This Gummy-refin is liable to great abufes, the larger mafies in particular, 
 are frequently no other than i'ome artificial compoficion, fkilfully incruftated 
 oil the outfide with a folution of Myrrh. Some report that Bdellium is nearly 
 allied to Myrrh, and not eafily to be diftinguifhed from it: The differences 
 however are fufftciently. obvious, Bdellium being darker coloured and lefs. 
 
 tranG 
 
Vegetable Juices. 317 
 
 tranfparent than good Myrrh, internally foft and tenacious which Myrrh never M y r rh- 
 is, yielding a quite different fmell, and wanting its bitternefs. v v ; 
 
 From fixteen ounces of Myrrh were obtained by means of water, twelve and 
 a half of gummy extrabt ; and from the refiduum by rebcified fpirit, one and a 
 half ofRefin. On treating the fame quantity fir ft with fpirit and afterward? 
 with water, I obtained five ounces of refinous, and eight ounces fix drams of 
 gummy extrabt, The indiffoluble matter amounted in both operations, to 
 two ounces, or one eighth of the Myrrh. 
 
 In diftillation with water, an effential Oil arifes, to the quantity of three 
 drams from a pound. This Oil fmells and taftes extremely ftrong of the 
 Myrrh, and contains all that part in which the peculiar qualities of the juice 
 refide : It differs remarkably from that of the other Gummy-refins, in not be- 
 ing hot or pungent* in being fo ponderous as to fink in water, and in not 
 being in the lead elevated by Spirit of Wine; highly rectified fpirit, diftilled 
 from Myrrh receiving no fenfible impregnation either in fmell or tafte. 
 
 It is further obfervable, that whether we digeft Myrrh in water or in fpirit,. 
 the whole of its fmell and tafte is taken up by the menftruum applied firft : An 
 extrabt made by water after fpirit has performed its office, and by fpirit after 
 water, are inodorous and infipid. Both the tinbture and the extrabt made by 
 pure fpirit at firft, contain all the abtive parts of the Myrrh: The watery infu- 
 fion or decobtion, if made in fuch a manner as to prevent evaporation, does 
 the fame but on exhaling it to the confidence of an extract, all the flavour of 
 the Myrrh is loft, and nothing but its bitternefs remains : No one can diftin- 
 guifh in the watery extract any thing of the fpecific characters of the Myrrh. 
 
 From theie experiments we learn, in what manner this juice is to be treated to, 
 the belt advantage, and in what preparations its virtues are preferved or loft. 
 
 It is obfervable alfo, that on inclofing fome powdered Myrrh in the white of 
 a hard boiled egg, and fetting it in a moift cellar, the liquor into which the 
 egg is by degrees refoived, extrabts nearly all the lmell and tafte of the Myrrh ; 
 that this liquor, commonly called Oleum Myrrha -per deliquium, is precipitated 
 or coagulated by Spirit of Wine ; and that the undtuous coagulum, feparated 
 from the fpirit, diffolves again in pure water. This procefs has been applied 
 likewife to Maftich and other pure Refins but from thole, as I have found 
 upon trial, the white of eggs extracts nothing, the liquamen not being diffe- 
 rent from that produced by the egg alone. 
 
 Phyflcians afcribe great virtues to Myrrh, and employ it is a balfamic, an- 
 tifeptic, attenuant and deobftruent 5 for promoting expedloration, perfpira- 
 tion, urine, the menftruai and haemorrhoidal difcharges, and the eruption of 
 the fmall-pox, dffc 
 
 TERRA JAPONICA, Catechu , Japan Earth, fo called from its XVL 
 having been long fuppofed by the Europeans to be an earthy fubftance found Terra 
 in Japan, is neither one nor the other. It belongs to the Clafs of Gummy- J AP0NICA 
 refins being fuch a combination of gummy and refinous matter, as the ex- 
 tracts made trom vegetables by water. In effebt it is no other than a prepara- 
 tion of this kind, obtained by infpiffating a watery decobtion or the expreffed 
 juice of the fruit of a certain Palm-tree, growing plentifully on the fea-coafts 
 
 1 
 
 
3 t 8 Vegetable Juices. 
 
 Terra in Coromandel, Cambaia, Bacaim, Manora, Daman, and feveral other parts 
 jAPONiCA.of the Eaft-Indies. The fruir, held there as a delicacy, is called faufe, its 
 w^-v*’****-' kernel areca , and the leaves of the tree betel: Hence the names of the plant, 
 Palma faufelifera , arecifera , &c. 
 
 The bell: Japan earth is that prepared by expreftlon, but the greater part of 
 what is brought to us is a true watery extradt. There are confiderable diffe- 
 rences in the produdl according to the manner in which the procefs has been 
 managed, and the degree of maturity or perfection of the fruit itfelf : That 
 Lime-water, Gum Arabic, Liquorice, Vitriol, or other like fubftances are 
 added, is a groundlel's conjedture. Some forts are of a pale reddifh-brown co- 
 lour, others of a dark blackifli-brown, or quite black like Bitumen ; fome are 
 ponderous, and others light; fome compact, and others porous ; fome more 
 and others Ids aftringent. The belt fort is of a dark reddifh-brown, 
 dry, heavy, hard, compadt and gloffy ; chewed, it difcovers at firft a bitterifh 
 ftyptic tafte, which is followed by an agreeable fweetnefs. 
 
 Japan earth, when pure is almoft totally diffolved, its aftringency at lead is 
 totally extradted both by water and fpirit. Four ounces of the beft I could 
 procure yielded with water, three ounces and fix drams of folid extradt ; after 
 which, rectified fpirit took up no more than twelve grains : The indiflbluble 
 part confided chiefly of fand, woody, and other foreign matters. Four ounces 
 of the fame Terra Japonic a, treated firft with rectified fpirit, gave juft three 
 ounces of refinous extradt : The refiduum {till yielded with water, five drams 
 two fcruples and eight grains of a gummy one. Another parcel yielded, on 
 the fame quantity, two drams more of fpirituous than of watery extradt : But 
 all the forts agree in the material points, namely (i.) That the fpirituous 
 tindture is of a redder colour, brighter, clearer, and more fluid than the wa- 
 tery, the latter appearing brownifh, quite thick, andatlaft curdly. (2.) That 
 the fpirituous extradt infpillated, proves ftronger, more aftringent, and more 
 difagreeable than the watery, the latter pofietfing the agreeable fweetnefs of 
 the 'Terra Japonic a itfelf improved rather than injured. (3.) That the extracts 
 made by water after fpirit, and by fpirit after water, have no remarkable tafte. 
 
 Flence where a ftrong aftringent is required, whether for external or internal 
 purpofes, we are diredted to the fpirituous tindture and extradt ; and for a 
 milder and more grateful corroborant, to the watery extradt. A little of this 
 Jaft taken into the mouth at bedtime, and fufifered (lowly to diflfolve, proves 
 remarkably lerviceable in diforders of the throat. 
 
 CLASS IV. 
 
 C A M P H O R. 
 
 T HERE are i undry Indian plants from which CAMPHORS are ob- 
 tainable, but only two which afford any large quantity, and from which 
 this commodity is commonly prepared, one growing in Sumatra and Borneo, 
 the other in Japan, as particularly about Satfuma. The firft is called by Brey- 
 nius Camphorifcra Sumatrana , &c. the Camphor-tree of Sumatra, with leaves 
 like thofe of the Clove-tree but longer pointed, a large oblong fruit, and a 
 
 very 
 
Vegetable Juices. 319 
 
 very large cup fomewhat refembling a Tulip : T he latter, Campborifera fiapo- Camphor » 
 
 mca, &c. the Camphor-tree of Japan, with Bay-like leaves, a fmall globular 
 
 fruit, and a very fhort cup. The Camphor of the japan fpecies is the only 
 
 fort met with in the rhops, the other being never brought into Europe. This 
 
 tree is about the fize of a large Lime, the flowers are white, the fruit is a fmall 
 
 red berry. All the parts of it are impregnated with Camphor, but the roots 
 
 contain mofl: Hence the roots are chiefly made ufe of for the preparation of 
 
 this commodity, though in want of fufficient quantities of thefe, the wood and 
 
 Eaves are mixed. 
 
 The Camphor is extracted by diftillation with water in large iron pots, on Method ofcb- 
 whit h are fitted earthen heads fluffed with draw ; greateft part of the Camphor tainin 6 u * 
 concretes among the ftraw in its cryftaliine form, and a part likewiie paflfes 
 down into the receiver along with the water. It is faid by fome to be ex- 
 tracted by fublimation without water ; but by fuch a proceis, it could not 
 avoid receiving from the woody matter, an empyreumatic fmell, which it is 
 never found to have. The rough Camphor, as firff diftilled, looks much like 
 the grey, fmall-cryftalled Eaft-Indian Saltpetre, or like common Bay-lalt : In 
 this ffate, it is imported in caniders, into Europe, particularly into Holland, 
 and there purified or refined. 
 
 The refining of Camphor was formerly one of the manufactures of Venice, Refining, 
 the Venetians being then the only people in Europe, who traded directly to the 
 Eaft-Indies. But that trade has long ago paffed into other hands : The Vene- 
 tians now import little or no Camphor, and the art of refining it is known 
 only to the Dutch The Engl i lb and French import fome rough Camphor, 
 but fend it to Amderdam to be refined, having never been able to fucceed in 
 the procefs themfelves. I have been in one of the larged refineries, in which 
 there were fifty furnaces, all managed by women ; and have feen the who e 
 operation after the matter had been put into the vefiels, but -no one is permit - 
 ted to fee it before. The purification is effected by fublimation, but doubtlefs 
 fome additional matter is made ufe of for keeping down the impurities of the 
 Camphor (r). The fublimation is performed in low flat-bottomed glades 
 placed in fand : The Camphor concretes, in the upper part of the belly of the 
 glafs into a folid cake, which, after the vedel has been broke, is pared with a 
 knife, and is now the refined Camphor of the drops. Gronovius has given a 
 good account of the method of managing the fublimation. 
 
 Pure Camphor is a dry colourlefs, tranlparent mafs, in appearance refemblingits general 
 a Salt, fo light as to fwim on water, moderately compact, yet eafy to break, properties, 
 though not reducible by itfelf into fine powder, foft, and as it were faponaeeous 
 to the touch when rubbed betwixt the fingers, of a drong penetrating fmell, 
 and an acrid aromatic tade, very eafily indammable, and fo volatile as to ex- 
 hale totally in a warm air. From thefe properties, it is obvious that Cam- 
 phor 
 
 (r) Refining ofi Camphor .] Camphor may fo warm as that the fublimate may bake to- 
 be refined by fublimation without any addi- gether into a cake. There is a good deal 
 fional matter. T he principal point is the of nicety in hitting this point; and upon 
 regulation of the fire which fliould be juft the whole, the method pointed out in the 
 ftrong enough to keep the Camphor fublim- following note feems to be more commo- 
 fng, and make the upper part of the glafs dious. 
 
320 Vegetable Juices. 
 
 Camphor. phor cannot be adulterated, much lefs counterfeited, as fome ridiculoufly pre- 
 tend, with Tallow, Maftich, and Spirit of Wine. In order to preferve this 
 volatile concrete from any lofs in keeping, the ancients covered it with certain 
 feeds, doubtlefs with a view to the more effectual excluding of the air: Some 
 have been hence milled into an abfurd conceit, that the feeds poffeffed fome 
 peculiar power of fixing the Camphor ; and it is at this time no uncommon 
 practice to put up a few Linfeeds, Pepper corns, &c. along with it. The only 
 method of preferving Camphor is, to keep it in a cool place fecured from the 
 air : If tied in papers or bladders, then put into leaden or tin canifters, or glafs 
 or earthen veffels, and fet in a cool cellar, we need not be afraid of lofing a 
 fingle grain in many years. I have kept Camphor tied in an ox’s bladder, in 
 the heat of boiling water, for an hour, without being able to perceive any fmeli 
 arifing from it during the codtion, or any diminution in its weight. 
 
 -Ufe in medi- Camphor, confidered as a medicine, is a very warm diaphoretic and antifep- 
 tic . i t does not however heat the conftitution fo much as might be expected 
 from its hot pungent tafte. I have been allured by an eminent phylician, that 
 a fingle drop of Oil of Cinnamon, though generally containing a little ex- 
 preffed Oil, heats more than ten grains of Camphor ; and an ounce of ftrong 
 
 Spirit of Wine, more than a whole dram Camphor is employed likewife in 
 
 In varniflies, fire- works, and in fundry other arts, particularly for varnifhes. Camphorated 
 $3c. varnilhes excellently preferve both animal and vegetable bodies, and peculiarly 
 
 refill worms and other infe&s. Camphor in fubftance alfo laid among clothes, 
 preferves them from moths. 
 
 Solution in Camphor dilfolves eafily and plentifully in vinous fpirits, and in oils : Four 
 different men- ounces of re&ified fpirit willdifiblve three of Camphor. When thus dilfolved, 
 itrua. we need not fear that any part of it will be dilfipated in a warm air, at lead: 
 
 till all the fpirit has exhaled firft ; for if the folution be committed to diftilla- 
 tion the fpirit will all diflill before any of the Camphor begins to arife ( s ), and 
 even if fet on fire, the fpirit will firft burn away, the Camphor remaining un- 
 touched till the fpirit is all conlumed, and then burning by itfelf with a quite 
 different, fmoky, footy flame. Among the mineral acids, the nitrous diffolves 
 it moft eafily and in largeft quantity : One part of Camphor diffolves readily 
 in two of Spirit of Nitre, but requires three of Oil of Vitriol, with the aflift- 
 ance of digeftion : The diluted vitriolic acid does not diffolve it at all ; and 
 the marine a<ffs fo languidly, that it may be doubted whether this acid diffolves 
 it any otherwife than by virtue of a portion of nitrous acid intermixed. Vinegar 
 and other mild vegetable acids, and alcaline liquors have no effedl on it. 
 
 The nitrous and vitriolic folutions afford fome very diflimilar phenomena : 
 The Camphor abforbs the more concentrated part of the nitrous fpirit, and 
 forms with it a fluid like Oil, which floats on the furface : With the vitriolic 
 acid it unites equably into one uniform liquor. To the nitrous acid it fcarcely 
 gives any tinge, the Oil being but juft fenfibly yellowifh, whilft the folution in 
 
 the 
 
 (j) Diffolved in fpirit — the fpirit diftih firjl .] 
 This property affords an effectual and com- 
 modious method of purifying Camphor. By 
 diifolving rough Camphor in rectified Spirit 
 of Wine, its impurities are feparated : The 
 
 fpirit is recovered by diftillation ; and the 
 remaining Camphor may afterwards be 
 melted into a cake in the bottom of the 
 vefiel, or of another glafs. The cake eafily 
 parts from the glafs upon warming it a little- 
 
Vegetable Juices. 321 
 
 the vitriolic acid is at firfb confiderably coloured, and on {landing becomesCAMPHOR- 
 more and more fo, changing at lad to a quite dark reddifh-brown. The vi- 
 triolic acid, if its quantity is large, deftroys the fmell of the Camphor, which 
 is not eafily concealed by any other menftruum. If water be mixed with the 
 folutions made either in Spirit of Wine or in acids, the Camphor inftantly fe- 
 parates, and relumes its original appearance and qualities. The addition of Sil- 
 ver or Quickfilver to the nitrous folution produces a like effecft, the acid letting 
 the Camphor go, and attacking the metal. It is obfervable that no heat or 
 effervefcence arife during the dilTolution of Camphor in the nitrous acid, 
 which railes fo violent a heat and ebullition with efiential Oils. 
 
 The principal preparations of Camphor are, camphorated Spirit of Wine, Preparations, 
 and an Oil of Camphor. The camphorated fpirit is no other than a folution 
 of Camphor in rectified fpirit. Some have thought to unite the Camphor and 
 fpirit more intimately together by diftillation ; but that procefs, inftead of 
 uniting, feparates them. Hoffman and Rothe diredl Salt of Tartar to be added 
 previous to the diftillation, and promife, by this method, a camphorated fpirit, 
 which will mingle with water, without any reparation of the Camphor. This 
 indeed the fpirit will do, for there is fcarcely any Camphor in it : It is in tome 
 degree impregnated with the fmell of that ftrong-fcented concrete, but the 
 quantity of adtual Camphor that arifes with it does not amount to above two 
 grains in a quart : No wonder that with fo fmall a proportion there Ihould be 
 no fenfible milkinefs or precipitation. 
 
 There are fundryOils of Camphor prepared by diftillation. One is madeOilsof Cam; 
 by diftilling Camphor from red Bole or other loamy earths, and repeating theP^ or ° 
 diftillation from a frefii parcel of the earth, till the whole of the Camphor is 
 changed into an Oil : This Oil has by fome been greatly efteemed, as no Cam- 
 phor feparates from it on the admixture of water. I tried the procefs with half 
 an ounce of Camphor, and two ounces of powdered red Bole, mixing them well 
 together, and urging them with a gradual fire in a retort : The Camphor arofe 
 much fofter than at firft, and in fome meafure umftuous, and on diftilling it 
 over a fecond time from the fame quantity of Bole, about one half of it became 
 fiuid. Both the liquor and the fublimate being mixed with two ounces more 
 of Bole, and the diftillation repeated, the whole of the Camphor arofe in the 
 form of a fluid Oil, with a little water, weighing together about an ounce. A 
 part of the inflammable principle of the Camphor appeared to be retained each 
 time by the ferrugineous matter of the Bole, all the refidua being confiderably 
 black and fparkling. 
 
 Another Oil of Camphor is prepared by digefting one part of Camphor with 
 four parts of Oil of Turpentine, and then diftilling them. Lemery relates, 
 that Camphor and Oil of Turpentine are of the fame degree of volatility, and 
 that they both diftil perfe&ly together. I repeated the diftillation in frefh re- 
 torts fix times fucceffively, but always found a part of the Camphor fublimed 
 by itfeif : There was alfo another more remarkable feparation •, a portion of 
 thefe fubtile volatile bodies remaining every time at the bottom of the retort, 
 and proving fo fixed as to bear a red heat. 
 
 A third Oil of Camphor is made from Camphor and Venice Sope, by diftil- 
 lation and cohobation, in the fame manner as the two foregoing : This is 
 
 T t called 
 
322 Vegetable Juices. 
 
 Camphor. called by fome Oleum camphor a arthriticunt. All the three have fomewhat of an 
 empyreumatic odour •, and confidered as medicines, are of little or no confe- 
 quence. Camphor is one of thofe drugs which. art cannot improve either for 
 medicinal or mechanic ufes ; and which are therefore to be given in their en- 
 tire fubftance, or unchanged in their compofition. All the afiiftance that the 
 phylician can in this cafe expeCt from the chemin, is, to difcover the molt 
 commodious means of fitting the fubjeCt for exhibition. 
 
 Fitted forme- For reducing Camphor into powder, and thus fitting it for fuch forms as re- 
 dicinal exhi- ce j ve powdery ingredients, it fhould be moiftened with a few drops of rectified 
 Spirit of Wine, which will render it eafily pulverable. Some endeavour to 
 impregnate water with Camphor, by fetting the Camphor on fire and quench- 
 ing it in water, but this is both an unfrugal and an ineffectual method. The 
 belt way of obtaining a watery folution of Camphor is, to grind it with Al- 
 monds, in the proportion of about four fcruples of Almonds to half a dram of 
 Camphor: By this means the whole of the Camphor will be rendered foluble 
 in water into the form of an emulfion. By agitating and grinding it with the 
 yolk of an egg [or with mucilages] it becomes likewife mifcible with water : 
 The yolk of one egg is fufficient for about two fcruples of Camphor. Sugar, 
 the common intermedium betwixt oily or refinous bodies and water, anfwers 
 lefs effectually for Camphor, and lets it go much fooner on the admixture of 
 watery liquors, than either Almonds or yolk of Eggs, 
 
 CLASS V. 
 
 GROSS OILS. 
 
 O i i s ^T'HESE kinds of Oils are always artificially extracted, by exprefiion or 
 X by coCtion in water. Oil Olive is obtained from the fruit of the 
 
 Oil Olive. Oka Sylvejlris or wild Olive-tree, of which there are large plantations and entire 
 forefts in Spain, Portugal, Italy, and other warm countries. The pickled 
 Olives are the green unripe fruit : The Oil is prepared from fuch as is ripe, in 
 which flate it appears of a blue colour, and about the fize of the fmaller kinds 
 of Plums. It ripens in November and December. The ripe Olives are kept 
 under cover for ten or twelve days, till they begin to'grow hot, then ground 
 betwixt two hard (tones, in the fame manner as the ingredients for gunpowder, 
 and afterwards preffed in bafkets made for that ufe. The Oil which runs out 
 firff, with very little preffure, is called Virgin Oil, and in effeCt is the bed. 
 After the feparation of this, the matter is mixed with a large quantity of hot 
 water, the liquor (trained off and (trongly preffed out, and this procefs re- 
 peated in fome places two or three times : The Oil arifes to the furface of the 
 water, aud is thence eafily fcummed off. Some repeat the grinding, as well, 
 as the exprefiion with water, and thus obtain Oils inferior in goodnefs. The 
 beft Oil Olive is that of Genoa ; but the greateft quantities come from Spain, 
 panicularlyffrom Seville. 
 
 OIL 
 
Vegetable J u 
 
 r c e s< 
 
 
 OIL of Ben is obtained from the Ben nut, ( B alarms myrepfua, glans Oil of Ben,. 
 unguent aria) by Ample expreffion, nearly in the lame manner as the Oil of Al- ^ c - 
 monds is commonly extraded. 
 
 Oils are exprefled alfo from different fubflances, among ourfelves, for me- 
 chanic ufes; as from Nuts, Linfeed, Rapefeed, Hempfeed, &c. and divers 
 machines have been contrived both for grinding and prefling the fubjebt. 
 
 THESE Oils are frequently employed as menftrua for the virtues of vege- Med: 
 table and certain animal fubflances. They readily unite with efiential Oils, O' 
 difiblve Reflns, and by the affiftance of heat, extract thofe principles from fuch 
 planes as contain them: The fubjebt is commonly boiled in the Oil, till the 
 watery moifture is difiipated, which is known from a little of the Oil, when 
 fet on fire, burning away quietly without fputtering. But though thefe Oik - . 
 excellently diffolve the adtive parts of many plants, the procefs is accompanied 
 with one great inconvenience, that all the exprefled Oils require a firong fire 
 to make them boil, far ftronger than water does, by which the Oil itfelf receives 
 an ungrateful impreflion, and the diflinguifhing flavour of the fubjedt is wholly 
 diflipated. If we boil an aromatic plant in Oil Olive, we fhali perceive its 
 irnell flrongly diffufed through the whole houfe, little or nothing of it being 
 left in the Oil. When thefe kinds of preparations therefore are wanted, they 
 fhouid be made by infufion with a gentle warmth, or by adding to Oil Olive 
 a fuitabie quantity of the efiential Oil of the plant. 
 
 THE more tender odoriferous flowers, which yield little or no efiential Oil Perfumed 
 
 Oils. 
 
 in diftillation, as Jafmine flowers, Violets, Tuberoles, Elyacinths, Lilies of 
 the Valley, Rofes, Jonquils, Clove July-flowers, and many others, give out w 
 their fragrance to exprefled Oils with little or no heat : The Oils diftinguiflied 
 by the name of thofe flowers, and ufed as perfumes, are no other than ex- 
 prefled Oils impregnated with their feent. Thefe preparations are made in 
 Spain, Portugal, and more particularly in Italy •, on account of the greater 
 fragrance of the flowers in thofe warm climates, and the greater plenty of Oil 
 of Ben, which is far preferable for this ufe to other Oils, as it does not grow 
 »ancid in keeping, or at leaft not till it has flood for a number of years. 
 
 The general method of preparing them is this. Some fine carded Cotton is 
 dipt in the Oil, and laid in the bottom of a proper vefiel : On this is fpread a 
 pretty thick layer of the frefh flowers, above thefe fome more of the dipt Cot- 
 ton, and thus alternately till the vefiel is full. The whole is then digefted for 
 a day and night in the heat of a water- bath ; after which the flowers are taken 
 out, the Cotton ftratified in the fame manner with frefli flowers, and the pro- 
 cefs repeated till the Oil fqueezed out from the Cotton, is found to be fuffi- 
 ciently impregnated with the odour of the fubjeef. The digefting vefiel is 
 either of Tin, with a cover to ferew upon it, or of Porcelane, compofed of 
 two parts, which are clofely luted together : Moft of them, have an air-hole in 
 the top, which is ftopt with a doflil of the oiled Cotton, which retains fuch of 
 the odorous effluvia as would otherwife make their elcape. Some, inftead of 
 the Oil of Ben, take the Ben nut itfelf, cut it in pieces, ftratify it repeatedly 
 
 T t 2 with 
 
324 
 
 V £ 
 
 G E T A 
 
 L E 
 
 J 
 
 VICE 3 . 
 
 Perfumed with the flowers, and ihen prefs out its Oil ; but the Oi! thus obtained is' 
 greatly inferior in fragrance to the other. 
 
 OjLofBAys. THE Oil of Bays, Oleum laurinum , is prepared by coftion, in 
 Italy, Spain, Portugal, and other warm climates. Frefh Bay- berries, tho- 
 roughly pounded, are boiled in water for a confiderable time; and the Are be- 
 ing then removed, the deco&ion, after its grofler parts have fubfided, laded 
 out of the caldron : When grown cold, the Oil is found fwimming on its fur- 
 face, of a thick confiftence like Butter. The remaining berries are further 
 pounded, prefled, again boiled in water, and this procefs feveral times re- 
 peated. Some keep the feveral Oils apart, others make only one fort, mixing 
 them all together. 
 
 PA L M OIL, Oleum palm .*?, is prepared in the fame manner, from a fruit 
 about the flze of a hen’s egg, called aouara. The tree which produces it re- 
 fembles a Palm-tree, and grows in Africa on the Senega river ; whence the 
 Oil is called by moft of the French writers, Huile de Senega ; by fome it is 
 named Huile de Pumicin. This Oil when frefh, has an agreeable fmell, and is 
 ufed by the Africans in food, as Butter among us. By age, it becomes firm 
 and hard like Tallow. 
 
 Palm 
 
 j 
 
 Oil 
 
 Oleum THE Oleum Cacao, ufed chiefly in pomatums, is obtained alfo 
 Cacao, by codtion and expreflion, from the Cacao or Chocolate nut, called by the 
 — v— — ^ Indians Cacahuatl. 
 
 Oleum THE Oleum de Ke rva. Oleum kikinum , or Oleum ficus inf emails, 
 de Kerva.Js extracted in the fame manner from the fruit of the Ricinus , called Grana 
 tiglia. 
 
 From diffe- 
 rent vege- 
 tables. 
 
 CLASS VI. 
 
 SWEET SALINE JUICES. 
 
 ’ANN A, lb called from its having been long fuppofed to defeend in 
 dew from heaven, like that with which the Ifraelites were fed in the wil- 
 dernefs, has been inconteftably proved to be the proper native juice of the tree 
 upon which it is found. The tree covered with clothes, a branch cut off and 
 carried into a cellar, have continued to bleed Manna as freely as when expofed 
 to the open air and dew. 
 
 In Perfia and Syria, a fpecies of Manna exudes in hot weather, from a 
 prickly fhrub, called by Tournefort Alhagi maurorum rauwolfii , by Cafpar Bau- 
 hin t GeniJla-fpartium fpinofum folds polygon!. This is faid to be Jels purgative 
 than ours, and not to keep above a year, whereas ours, if preferved in a proper 
 place, continues good for at leaf!: five years. 
 
 Dr. Grim and Dr. Helbig, in the Ephemerides naturae curioforum ann. i. give; 
 an account of a fubftance in appearance, confidence and tafte, refembling 
 Manna, found upon certain trees in Ceylon and the Eaft-Indies : But as this 
 
 fubftance 
 
E 
 
 Vegetabl 
 
 ! u i e 
 
 fubdance is faid to be prepared by infers, it may perhaps be more properly M a n n a* 
 looked upon as a concrete Honey than a Manna. v_ V*''*‘ * ... w/ 
 
 In Dauphiny, Provence, and tome others of the fouthern parts of Europe, a 
 Manna exudes from the Turpentine and Larch trees, but in fmall quantity,, 
 and not eafily to be coliedfed pure. 
 
 The common Manna of the Hops is the produce of a fpeoies of the A(h tree, Different 
 Fraxinus rotundiore folio, C. B growing in Naples and Sicily, particularly in ^; nr! of j £ j‘ e 
 the province of Calabria. The juice exudes IpontaneouAy, in the hot dry 
 weather of June and July, upon the leaves, the branches, and tl*e trunk of 
 the tree; that col ledled from the leaves is called Manna di ftonda, from the 
 branches Manna diramo , and from the trunk Alamia di corpo: This didindtiou 
 is of iittle importance, as the juice is always the fame whatever part of the 
 plant it iffues from, as much fo, as the blood drawn from different parts of an 
 animal body. Thefe fpontaneous exudations are the fined, whited, and pure ft 
 Manna, being naturally filtered and lecreted from the groffer parts : JBur if 
 
 there was no other, Manna would be rare. When nothing more will exude, the 
 bark is wounded with knives; upon which the juice iffues more copioufly, but 
 of a yellowifh colour, and a groffer and thicker confidence. In dry weather 
 the Manna foon concretes, and is then fcraped off, to make roc5m for the juice 
 that is to follow.. The Manna thus collected is called Manna sforzata , or forced 
 Manna. As watery moifture would difpofe it to ferment, and turn four or 
 mouldy, it is further exficcated by the fun’s heat, or in a warm room ; but 
 fufficient cafe is taken not to diminilb its weight too much by making it tho- 
 roughly dry. 
 
 Thofe who purchafe this commodity at the firft hand, divide it into four 
 forts ; Manna granata , or Manna in fmall grains ; Manna majiichina , or Manna 
 in larger grains like Maftich ; Manna cannellata , or eledla, or fuch as is in fine, 
 pure, long pieces ; and Manna commune , or the ordinary foul Manna. In the 
 fhops, only the two laft are diflinguifhed. 
 
 Fine Manna is in oblong, roundifh, Angle pieces, moderately dry, of aDefcriptionos 
 whitifh or pale yellowifh colour, internally compofed as it were of fine capil-the beft fort, 
 lary cryftals, a proof that the juice has been exficcated by a very gentle warmth. 
 
 The ordinary kind is of a darker yellowifh colour, inclining to brown, mixed 
 with particles of wood, leaves, and other impurities, in irregular lumps, gene- 
 rally moift. The whitends, drynefs, lightnels, purity, cryftalline appear- 
 ance upon breaking, and fweet fade, are the bed marks of the goodnels of 
 Manna. 
 
 Manna is often counterfeited or fophifticated with other fubftances, parcicu- Sophiftica 
 larly Sugar and Starch. Thefe may be difeovered by diffolving the mafs in ons. 
 water, and infpiffating the foliation, when the adulterated forts will turn out 
 far more clammy and tenacious than the genuine, and quite different from it in 
 appearance. Sugar may likewife be diftinguifhed in good meal ure by cryftal- 
 iization : If the drained folution be evaporated to the confidence of a thick 
 fyrup, and then fet in a ciofe warm place, apart of the Sugar will generally 
 concrete into Candy. There are iome forts of Sugar however, which do not > 
 eafily feparate in this procefs from the Manna, but remain permanently united, 
 with it. The Angular phenomena which I have uncovered in treating this, 
 
 i concrete: 
 
326 
 
 Vegetable Juices. 
 
 Mann a. concrete with Spirit of Wine, afford more commodious and more certain cri- 
 
 
 
 Purification 
 by Spirit of 
 Wine. 
 
 Treated 
 
 water. 
 
 by diftillation. 
 
 teria of its genuinenefs. 
 
 Manna, dried a little, diffolves in redi Bed Spirit of Wine. The filtered 
 folution fet in a gentle digefting heat, throws oft' near five-eighths of the origi- 
 nal quantity of the Manna, all over the bottom and lides of the glafs : The 
 part thus feparated, is as it were the quintefience of the Manna : It is of a fine 
 white colour, light, ipongy, in fome degree cryftalline : It inftantly melts 
 upon the tongue, like fnow in warm water, and impreffes an agreeable fweet 
 tafte, without any thing of the ungrateful relifti obferved in the Manna at firft. 
 If the remaining liquor be gently exhaled a little, and at times fet by again, 
 there precipitates about one fourth the quantity of the Manna employed : This 
 refembles in appearance ordinary Manna, but taftes more agreeably, and dif- 
 folves pretty readily in the mouth, though not near fo much fo as the forego- 
 ing. On (till further evaporating the liquor, we obtain a thick extract, of the 
 confiftence of a Balfam, which can fcarce be fully exficcated, but continues' 
 moift, and greatly refembles in appearance Civet grown brown by age : In this 
 extrad, whole quantity is about one eighth, refides all the naufeous matter of 
 the Manna : It has indeed a degree of fweetifh tafte, but blended with a dif- 
 guftful one. 
 
 wit\ On diflblving Manna in water, and flowly exhaling the folution, no repara- 
 tion is made : The whole quantity of the Manna is recovered, unchanged, ex- 
 cept that the colour proves fomewhat darker. 
 
 In diftillation. Spirit of Wine brings over nothing: The diftilled water 
 taftes fomewhat differently from pure water, but does not appear to polfefs 
 the purgative quality which fome have afcribed to it, though it is certain that 
 Manna lofes of its cathartic virtue by much boiling. Some report, that water 
 diftilled from a mixture of Manna with twice its weight of Nitre, taftes like Bit- 
 ter Almonds, and have given to the liquor the name of Manna meteorizata. I 
 have repeated the experiment with great care, but could not perceive the leaft 
 degree of any fuch tafte in the diftilled water. 
 
 By deftrudive diftillation in a ftrong fire, a pound of Manna yielded twelve 
 ounces two drams of a phlegmatic liquor impregnated with acid and with a 
 fetid Oil as alfo two drams and a fcruple of an empyreumatic Oil diftind or 
 in its proper form : The remaining coal weighed three ounces and one dram. 
 The acid fpirit has been faid to diffolve Gold : This prefumption probably 
 proceeded from thole philofophers, who imagined a certain aereal fpirit to be 
 the radical menftruum of Gold, and Manna to be an aereal produdion largely 
 impregnated with that fpirit: The acid fpirit of Manna, however concentrated, 
 has no adion on Gold, nor any other powers different from thofe of the com- 
 mon acetous acid. 
 
 by fermenta- Lemery has given fome experiments on Manna in the French Memoirs for 
 the year 1708 : He obferves that when fermented with water, it yields a weaker 
 and Iefs agreeable liquor than the Mead made with Honey that two pounds 
 of Manna yielded, after fermentation, eight ounces of a weak vinous lpirit, 
 which afforded only one ounce and a half of redified fpirit ; that the refiduum, 
 fet by to four in a warm place, for a year and a half, gave feven drams of an 
 effential Salt, which was white, hard, brittle, and cryftallized into the form of 
 
 needles. 
 
 tion. 
 
Vegetable Juices. 327 
 
 needles. This Salt is to be looked upon as of the Tartar kind ; not as being A N N 
 extracted, but produced, from the Manna. 
 
 Manna appears upon the whole to be a juice of the fame nature with Ho- its medical 
 ney and Sugar; being like them fweet, inflammable, folubie in Water and ules * 
 in Spirit, fermentable fo as to yield a vinous liquor and fpirir, a Vinegar and 
 Tartar, &c. It poflefles alfo, like them, a laxative quality, but in a greater 
 degree. 
 
 Manna is one of the mildefl: and fafefl purgatives, for children and weak 
 perfons, in coughs and obftnnftions of the bread, where mineral Waters do 
 not freely pals, in cafes where the ftronger cathartics cannot be borne. It has 
 one inconvenience, being apt to occaflon flatulencies and flight gripes : This 
 may be remedied by carminative additions. 
 
 SUGAR is the eflfential Salt of a fpecies of Reed or Cane (Arundo jj 
 faccharifera C. B.) growing fpontaneoufly in Africa and Afia, and cultivated in g u g a r 
 large quantity in the Englifh, French, and other European fettlements in the t 
 warmer parts of America, where all our Sugar is prepared. A kind of Sugar 
 is obtained likewife in the Eafl: Indies from certain trees and other vegetables; 
 and fome of our own plants alfo afford afaccharine concrete (r). 
 
 The 
 
 (r) Sugar from certain trees , tffc.] In fome 
 parts of North America, particularly in 
 Canada, a kind of Sugar is prepared from 
 the juice which iffues upon wounding or 
 boring certain fpecies of the Maple-tree, 
 one of which is named from hence the Su- 
 gar-maple ; as alfo from the wild or black 
 Birch, the Honey-locufl, and the Hickery. 
 The Maple is mofl commonly made ufe of 
 for this purpofe, as being the richeft, and 
 as beft enduring the long and fevere win- 
 ters of that climate. The juice is boiled 
 down, without any addition, to a thick 
 confiftence, then taken off from the fire, 
 kept ftirring till its heat is abated, and fet 
 in a cold place ; where the Sugar quickly 
 concretes into grains, refembling common 
 brown powder Sugar. 
 
 The trees are tapped early in the fpring, 
 about the time that the Snow begins to 
 melt : It is obfervable, that when the wea- 
 ther begins to grow warm, they bleed no 
 more ; and that after the bleeding has ftopt, 
 they begin to run again upon covering the 
 roots with fnow. The more fevere the 
 winter has been, the juice is found to be 
 the richer and in greater quantity. The 
 trees which grow on hills or high lands 
 yield a richer juice than thofe which are 
 produced in low countries ; and the middle 
 aged than the young or the old. 
 
 Mr. Kalm informs us, in the Swedifh 
 tranfadlions for the year 1 75 x, that one 
 tree, if the fummer does not come on haf- 
 tily, will yield about forty-two gallons of 
 juice, (Englifh Wine-meafure,) and that 
 the quantity which iffues in one day is 
 from three to fix gallons : That eleven 
 gallons of juice of middling quality give a 
 pound of Sugar, and that fometimes a 
 pound has been gained from three gallons 
 and a half : That two perfons can in one 
 fpring prepare commodioufly two hundred 
 pounds. He obferves that this Sugar is 
 weaker than that from the Sugar-cane, 
 but that for fome purpofes it anfwers better, 
 as for Chocolate and Preferves. It is like- 
 wife efteemed more medicinal : Confider- 
 able quantities are brought annually into 
 Europe, particularly France, and there em- 
 ployed in diforders of the breaft. It is rec- 
 koned that a pound of common Sugar goes 
 as far in fweetening as two pounds of 
 Maple Sugar. 
 
 The large Maple, commonly called Sy- 
 camore-tree, bleeds alfo in Europe a fweet 
 juice, from which an actual Sugar has been 
 prepared. In the Tranfadtions above-men- 
 tioned, for the year 1754, there is an ac- 
 count of fome experiments made in this 
 view upon the Swedifh Maple. Eight 
 trees, none of them under thirty years, 
 
3,28 Vegetable Juices. 
 
 Sugar. The Sugar-cane arifes to the height of five or fix feet : It has long leaves,. 
 
 u {harp at both ends and produces in the middle a kind of arrow, bearing filver 
 Hiftory of its wh.ite flowers : It fends out fuckers from the roots, by which the plant is pro- 
 prepanuion. p a ga tec ^ When the Cane is ripe, it is cut down, cleared from the leaves, 
 and its fweet juice forced out by pafling betwixt wooden rollers : In one mill there 
 are commonly three rollers, placed perpendicularly, and turned by Water, 
 by wind, or by cattle. The juice is conveyed from the mill, along a trough 
 or fpout into the boiling -houfe, either immediately into the boiler, or into a 
 felervoir : It will fcarcely keep above a night, without fermenting, and turn- 
 ing four, or producing a portion of inflammable fpirit, fo as to be apt to 
 take fire in the boiling, and endanger the whole building : Hence the 
 neceffity of boiling it down into Sugar as faft as it is prefled out from 
 the Cane. 
 
 This juice contains a large quantity of impurities, confifting partly of a 
 grofs undtuous and herbaceous matter, leparable by colature, and by defpu- 
 m at ion during the boiling; and partly of an oily fubftance more intimately 
 blended, fo as to require for its leparation certain additions, as alcaline ley, 
 and more particularly Lime-water : Without thefe additions, it never aflumes 
 the form of a concrete Salt or Sugar, yielding only a foft undtuous extract, 
 which cannot be reduced to perfedt drynefs without fuch a degree of fire as 
 renders it fetid and empyreumatic. After the firft boiling and defpumation, 
 the juice is emptied into other coppers, a quantity of a ley, made from wood- 
 afhes or from afhes and Quick-lime, added to it, and the codtion and clarifi- 
 cation continued. When, towards the end of the infpififation, it rifes up, fo 
 as to be ready to run over the veflel, the addition of a little oil occafions it 
 quickly to fubflde again : It is obfervable, that if Oil, or Citron juice, were 
 added in the firft boiler, the Sugar would never concrete or part from its im- 
 purities. The Sugar, thus obtained, is far from being pure : It is the com- 
 mon brown Mufcovado. This is further refined by diffolving it afrefh, boiling 
 with Lime-water and ley, and clarifying with oxes blood ( s ) : The Sugar- 
 
 refiners 
 
 bled, in four days, fourteen gallons of 
 juice, which inl'pillated gave two pounds 
 and a half of brown Sugar. Another time, 
 the fame eight trees bled, in three days, 
 ten gallons and a half, which yielded one 
 pound four ounces of Sugar, with half a 
 pound of Syrup. It is the Saccharine juice 
 of the Maple-tree, which, exuding upon 
 the leaves, renders them fo apt to be preyed 
 upon by infects. 
 
 The common Birch bleeds alfo a large 
 quantity of a fweetifh juice, which yields 
 or. being infpiffated a fweet faline concrete, 
 not however perfectly of the Saccharine 
 kipdi, but Teeming to approach more to the 
 nature of Manna. 
 
 There are lunary other vegetables, raifed 
 T bur own country, which afford Saccha- 
 
 rine concretes ; as Beet-roots, Skirrets, 
 Parfneps, Potatoes, Celeri, red Cabbage- 
 flalks, the young fhoots of Indian Wheat. 
 The Sugar is moft readily obtained from 
 thefe, by making a tintfture of the fubjetft 
 in rectified Spirit of Wine ; which when 
 faturated by heat will depofite the Sugar 
 upon Handing in the cold. 
 
 (r) Refining of Sugar. ] The author has here 
 overlooked an eflential part of the procefs. 
 The Sugar, diffolved in Lime-water, clari- 
 fied, and boiled down to a due confidence, 
 is poured into a conical earthen mould, 
 having a fmall aperture in its lower narrow 
 part flopped with a plug. When the Sugar 
 has concreted into a mafs, the liquid part 
 is drained off by the aperture ; and fome 
 
Vegetable Juices. 329 
 
 refiners at Orleans in France and in England ufe whites of eggs for the dari-S u c a r. 
 'fication, particularly in making the fine Sugar. By repetitions of this procefs, 
 the Sugar becomes purer, whiter, of a cryftalline appearance, but proportion- 
 ably lei’s fweet. A fyrupy matter feparates in the purification, called from its 
 honey-like confidence Melafifes or Melazzo : From this are produced, by fer- 
 mentation, the common inflammable fpirits, difiinguifhed by the name of 
 Melafifes Spirits. In America, the fcummings alfo, and other refufe parts of 
 the juice, are fermented for vinous liquors and Rum. 
 
 Sugar appears to be a Salt of the acid kind, faturated with earthy and oily Chemical 
 matter, on which its fweetnefs depends ; hence the diminution of its fweetneisP r0 P ertie£ * 
 in proportion to its purification or the reparation of the Oil. Diftilled by a 
 gradual fire, without addition, it yields, on the pound, about fix ounces of 
 acid fpirit, and two fcruples and a half, or a dram, of empyreumatic Oil. 
 
 Gently roafted, it acquires a reddifh brown colour, and in this date, is ufed 
 for colouring vinous and fpirituous liquors yellow. By fermentation it yields 
 an excellent kind of Wine ; and by a continuance of the procefs, Vinegar. 
 
 With regard to mixture with different folutions and other liquors, it is per- 
 fectly neutral ; making no alteration in thofe which by acids or by alcalies 
 would be precipitated or have their colour changed. It renders effential 
 Oils, Balfams, Refins, mifcible with watery liquors : Hoffmann obferves that 
 when added to milk, it prevents the feparation of its oily or butyraceous part. 
 
 From this property he fuppofes the dietetic ufe of Sugar to be fattening, as it 
 renders the unftuous or fat parts of the food mifcible with the animal juices : 
 
 I have known however many people, who ufed Sugar in abundance, and yet 
 were lean. It diffolves in rectified Spirit of Wine by the affiftance of heat; but 
 is fcarcely aCted upon by that menftruum in the cold (/). 
 
 Many 
 
 fine Clay, foftened with Water into a pafte 
 or batter, is fpread upon the upper broad 
 furface „• The moifture of the Clay, flowly 
 imbibed by, and percolating through the 
 Sugar, carries down with it great part of 
 the remains of the treacly matter. The 
 clayed Sugars, brought from America, are 
 made from the juice direCtly, without a 
 fecond folution ; the liquor being more 
 carefully depurated in the boiling, than when 
 intended for brown Sugar. 
 
 Sugar-candy is a cryftallization of Sugar; 
 prepared either from the brown or the 
 white. The perfeCt cryftallization of Sugar 
 is not to be effected, like that of many 
 other Saits, by evaporating the liquor in 
 which it is diftolved, till a pellicle forms on 
 the furface, and then fetting it in a cold place ; 
 but by boiling down the folution till it is 
 almoft thick before it is removed from the 
 fire, and afterwards continuing a confider- 
 able heat, till the cryftallization is com- 
 pleted. The Sugar is diftolved in Lime- 
 water, and when evaporated to a proper 
 
 confiftence, poured immediately into 
 pans, in a ftove or hot room, whofe air 
 is fo hot as not to be fupported by animals 
 for any confiderable time : The cryftals 
 concrete upon fmall fticks, which are 
 placed acrofs in the pans for that pur- 
 pofe. 
 
 (t) Solubility in Spirit . ] Rectified Spirit of 
 Wine diffolves, by a boiling heat, about 
 one twelfth its weight of fine Sugar ; if the 
 folution be fuffered to ftand for a few days 
 in the cold, the Sugar gradually feparates, 
 and concretes into elegant cryftals. On this 
 principle depends the method of extracting 
 Sugar from fweet Vegetables by means of 
 Spirit of Wine : Water diffolves the lac- 
 charine parts of the fubject more readily and 
 more copioufiy than fpirit does, but it keeps 
 them permanently diftolved, and intermixed 
 with the gummy or other matter which it 
 had extracted at the fame time ; whereas 
 pure fpirit depefites the Sugar, and keeps 
 the refmous or oily principles diftolved. 
 
 U u 
 
220 Vegetable Ju 
 
 Sugar? Many of the Indians employ Sugar inftead of Salt for preferving provifions,. 
 
 which it does effectually, without communicating the unfalutary qualities of 
 falted meats : The Sugar may be walked out, infpiffated, and ufed for the 
 fame purpofes again. From this property it has been employed by furgeons 3 . 
 as a balfamic and vulnerary. 
 
 ICES. 
 
 CLASS VIL 
 
 'Jukes colletled from Vegetable Subfances by Animals „ 
 
 I. 
 
 HONE Y. 
 
 Honey np^E HONEY and Wax, gathered by the Bee, are truly Vegetable 
 ^ _ ' J J, Juices. Honey is collected from the bottoms of flowers, many of which 
 difeover a confiderable fweetnels to the take. Among the flowers which yield 
 the mod, are thofe of Thyme, Rofemary, Lavender, Cowflips, Primroles, : 
 Marjoram, Bafil, Violets, Rofes, Clove-july flowers, Sage, Balm, Betony, 
 Lilies, the dead Nettle, Sloe-bufh, Bees are uncommonly fond of the 
 
 Lime-tree, the Privet and Phillyrea. In Lithuania, there are large quantities 
 of wild Bees, who lodge in hollow trees in woods, and colled their Honey 
 chiefly from the Lime : Hence, when the feafon happens to be unfavourable 
 at the time of the blowing of the Lime, a fcarcity of Honey follows. Bees 
 love agreeable fmells ; and are offended by fetids, as Feverfew, Garlic, 
 Onions, Tobacco, &V. They love green and yellow colours, and are offended 
 by black and red. 
 
 Whether dif- The ancients judged of the goodnefs of Honey from the flowers which the 
 ferent in dif- bees had to coiled: it from : That of Lilies and Roles was efteemed the befh 
 ferentflower s-yyt prefent, the Ploney of Narbonne in France is held to excel all others, on 
 account of the Rofemary which there abounds. It is not to be fuppofed how- 
 ever that the Bee confines itfelf to one particular flower : Nor does it appear, 
 that the Honey collected from one kind of flower differs effentially from that 
 which is the produce of another ; the only difference being in the quantity, 
 colour, or fome flight flavour from the flower. I have feen excellent Honey 
 produced where nothing grew but nettles and other weeds. 
 
 We meet with Honey of different degrees of confiftency and colour ; fluid 
 and ftiff *, dark brown, dark yellow, gold yellow, pale yellowifh and white. 
 The belt is that which is of a yellow or pale colour, clear and tranfparent, 
 neither quite ftiff nor quite fluid, eafily and totally folubfe in cold Water, of 
 an agreeable fmell, and a pure fweet take : Such as betrays any particular 
 flavour, does not eafily dilfolve, or depofltes any fediment, we may fufpeCt 
 of fome foreign admixture. Some think to improve their Honey, by com- 
 municating by art what the Honey of Narbonne is imagined to receive from 
 nature, a Rofemary flavour. Others dilute thick Honey with Water, and 
 mix meal with the thin. The brownifh and dark brown are generally very 
 impure. The whitifh, and the granulated, or that which difeovers crystalline 
 particles, more flow of folution than the reft, are not to be rejected : They 
 are both good kinds of Honey, provided they are pure from other admix- 
 tures——. 
 
 Its different 
 forts. 
 
Vegetable Juices* 33E 
 
 Cures— ■ - — The manner in which the Honey is extracted from the comb occa-HoNE y„’ 
 lions fome differences in its quality. That which iffues fpontaneoufly upon U— y * — j 
 cutting the combs and thus laying open the cells, is the beft : Such as is 
 forced out by preffure is of an inferior kind ; and the word of all is that ex- 
 tradited by Water: The two laft contain much of the waxy and, other 
 
 matter of the comb. The Honey gathered by young bees, in the firft year, 
 and feparated from the combs without heat or preffure, is that properly called 
 Virgin Honey : In the fhops, the liner forts in general are diftinguilhed by 
 this name. 
 
 Honey was the earlieft fweet employed for medicinal or domeftic ufes ; the Its ufes, and 
 art of preparing Sugar being but of late difcovery. It differs from Sugar chemical ex- 
 chiefly in its confidence, never affuming a concrete of folid form (u), and its amir iation. 
 poffeffing a greater laxative, expectorant and detergent quality. It is obferv- 
 able that fome have a peculiar averflon to its ufe, and cannot bear it even 
 externally. In the (hops, it is employed as the bafis of fome eleCtaries, me- 
 dicated Honies, Oxymels, &c. which may be feen in difpenfatories. It is 
 purified from waxy, farinaceous and other like matters, by liquefying it in a 
 gentle warmth, taking off the fcum which ariles to the furface, and paffing 
 the Honey through a linen cloth. It fhould never be boiled, as its finer and 
 more fubtile parts are in that procefs diffipated ; and an ungrateful impreffon 
 made upon it by the heat. The liquor which arifes even in the heat of a 
 Water-bath is manifeftly impregnated both with the fmell and tafte of the 
 Honey : It amounts to three ounces upon eight of Honey. The Honey thus 
 infpiffated diffolves, as at firft, both in Water and in rectified Spirit of Wine, 
 only a fmall portion being left. The vapour which exhales in the boiling, 
 takes flame from the approach of a candle, diffufes its fmell throughout the 
 houfe, and will draw together a whole fwarm of Bees from a great diftance. 
 
 In diftillation by a gradual fire without addition, thirty-two ounces of Honey 
 yielded upwards of twenty-four of an oily acid fpirit, with a little empyreu- 
 made Oil : The remaining coal weighed upwards of feven ounces, and like 
 that of Manna, could fcarce be reduced into allies. The acid fpirit has been 
 laid to diffolve gold and quickfilver; but I have not obferved it to have any 
 addon on either of thefe bodies, or to differ in its diffolving power from the 
 acid of Vinegar. Nor does there feem to be any foundation for the virtue 
 commonly al'cribed to this fpirit and to the diftilled Water of Honey, of 
 making hair grow. The principal confumption of Honey is in ginger-bread, 
 and for making Mead and Metheglin. Thirty-fix ounces of Honey, diluted 
 with four quarts of warm Water, and fermented with a little yeaft, yielded 
 
 on 
 
 (u) Concrete form .] Though Honey does 
 not concrete into a cryftalline or laline 
 mafs by the ufual methods of evaporation 
 and cryftallizadon ; I have neverthelefs 
 made it to afiume that form by a variation 
 of the procefs ; by treating it in the manner 
 pradtifed for the refining of Sugar. The 
 Honey, clarified and boiled down to a due 
 confiftence, and then poured into a conical 
 
 mould perforated at the bottom, concretes 
 into a folid mafs, and difeharges a liquid 
 treacly matter. The lump, at firft hrownilh 
 or yellowifh, by fpreading moift clay upon 
 the furface becomes white : It is moderately 
 firm, of a cryftalline appearance, and a 
 very fweet tafte, different from that of Su- 
 gar, and not quite the fame with that which 
 the Honey had at firft, 
 
 U 2 
 
332 Vegetable J u 
 
 Hone Y.on diftillation a pint of phlegmatic fpirit, which by rectification was reduced 
 
 to eight ounces 
 
 II. 
 
 THE bees employ in building their combs two kinds of fubftances, one, a 
 
 Bee-glue, foft, unCtuous, glutinous matter, the other, Wax. The firft ferves as a Glus 
 U— — v— — ' for cementing the combs to the hives, and clofing up the cells : Hence it is 
 
 called Bee-Glue. A portion of this commonly adheres where the bees 
 alight, and may befcraped off from about the entry of the hive : It was for- 
 merly kept in the ihops under the name of Propolis, but is now entirely in 
 difufe. 
 
 Method of 
 whitening, 
 
 HI. WAX is collected from leaves and flowers, particularly from thofe flowers 
 W a x. which are well furnifhed with ftamina, or threads bearing little knobs on the top : 
 - — - 1 The fcamina of the common Poppy and Rocket yield to the bee abundance— 
 J'^ nce P r0 * In the Ephemerides nature curio forum there are two accounts of a little waxy mat- 
 ter being obtained in beating Rofes. In fotne parts of America, a kind of 
 Wax is collected from trees. 
 
 Wax is atfirft white, as we fee in the cells of young bees : The yellow co- 
 lour which it acquires afterwards is fuppofed by fome to proceed from the 
 Honey. This colour is not permanent : By kneading the Wax, or by long 
 
 keeping, it lofes its lively yellow and becomes whitifh : Melted by common 
 Are, it turns darker coloured, but by expofure to the fun it grows at length 
 white as fnow. Thofe who bleach Wax for candles and other ufes, caft it into 
 thin plates by melting and pouring it upon a roller turning round in cold water, 
 and fpread the finefhivers into which it is thus divided, upon a linen cloth, in 
 the fun : When the outfide is fufficiently whitened, the Wax is melted and 
 caft into thin plates again, that a frefh furface may be expofed to the fun, and 
 this procefs three or four times repeated. The bleaching is begun and ended 
 
 with the warm part of the year The Wax is procured at firft by melting 
 
 over a gentle fire, the matter left after the expreflion of the Honey, fcumming 
 off the lighter impurities which arife to the furface, and pouring it into a moift. 
 wooden veffel : When the cake of Wax congeals, the groffer part at the bot- 
 tom is pared away. 
 
 examined by Bees- wax, when in perfection, is of a deep, bright yellow colour, and a 
 jnenftrua and ftpong, agreeable Honey -like fmell, both which it lofes upon long keeping. 
 
 In bleaching, the fmell is deftroyed along with the colour. It is not whitened, 
 as fome pretend, by Spirit of Wine : By the afilftance of heat, it totally dififolves 
 in that menftruum, and when recovered from it again proves darker coloured 
 than at flrft. Water has no aCtion on it. Diftiiled by a gradual fire, without 
 addition, it almoft totally arifes in form of a butyraceous Oil, which grows 
 ftiff in the cold like Wax itfelf, and liquefies again on applying heat : Four 
 ounces of Wax yielded four ounces of Oil, wanting only about a fcruple ; that 
 which comes over firft is whitifh ; that which follows, more of a brownifh hue. 
 Boerhaave recommends this Oil as an extraordinary remedy againft chaps in the 
 breads. The principal ufe of Wax in medicine, is in cerates, plafters, oint- 
 ments, &c. It is ufed alfo internally as an ingredient in the Balfamum Locatelli , 
 which is given in afthmatic diforders, and for healing ulcerations, but probably 
 
 on 
 
 diftillation. 
 
Vegetable Juices. 
 
 on no juft foundation, Wax is a tenacious fubftance not made for the human 
 ftomach todigeft: The Turpentines and Balfams, whatever may be their good 
 effe&s when externally applied, heat and ftimulate when given inwardly, and 
 thus leem more likely to aggravate the febrile fymptoms that accompany con- 
 fumptive diforders, than to heal the ulcerated lungs, which how great foever 
 we luppofe their healing power, they certainly cannot reach. The mechanic 
 ufes of Wax are numerous, as for taking impreflions, for anatomical inje&ions, 
 candles. Sealing-wax, for waxing thread,, as a varnifh to cover Copper for 
 etching with Aqua fortis, &c. &c. 
 
 GUM LAC, fo called, has been fuppofed to exude in the Eaft-Indies, 
 from punftures made in the barks of trees by certain winged infedts. It appears j c * 
 to be truly a kind of Wax, colledted by the infedfc, and formed into regular / A 
 cells like the honeycomb. It is found upon different kinds of trees, and not 
 only upon living trees, but on fticks which the Indians place in the ground for 
 the infedft to work upon. There are indeed natural exudations, called Lacs 
 from their ufe in lacquers and varnifhes ; but thefe are entirely different from 
 the Lac brought to u«. 
 
 Gum lac is of a red colour, not of itfelf, but from the infedfc, In many of cifferent 
 the cells there are dead inle&s, whole colour is gradually diffufed by the fun’s forts, ufes, 
 heat, through the whole fubftance of the cell r Such maffes as the infedts haveLft. 
 not died in, or have not been expofed to the adtion of the fun, or have been 
 gathered too foon, have little or no rednefs. The greateft quantities are 
 brought into England and Holland, from Malabar, Bengal, Pegu, Suma- 
 tra, &c. in maffes adhering to the fticks or branches of the tree, and hence 
 called Stick lac, Laccain baculis, ramulis , furculis. This is employed in fundry 
 places for dying lcarlet (z), and for colouring leather : It is with this that the 
 Turkey leather is ftained. The Lac, beat off from the fticks, is reduced into 
 a grofs kind of powder, and a tindlure extraded from it ; after which the re- 
 maining 
 
 The quantity of dried Fecula amounts to a 
 little more than one fifth the weight of the 
 
 Lac. 
 
 For dying, this Fecula is difiolved in 
 warm water, with the addition of a proper 
 quantity of folution of Tin ; and the fiery- 
 red liquor poured into boiling water impreg- 
 nated with Tartar, after the fame manner 
 as when Cochineal is ufed : The only diffe- 
 rence is, that the Fecula ofGum lac dif- 
 folves more difficultly than Cochineal, and 
 hence is rnoft conveniently difiolved firft by 
 itfelf; and that it affords fomewhat more 
 colour. If, inftead of Tartar and folution 
 of Tin, any fixedalcalineSalt.be ufed, the 
 vivid red of the Gum lac changes into the 
 colour of red-wine lees : Sal ammoniac 
 changes it to a Cinnamon or Chdhut co=> 
 lour. 
 
 (z) Dying fear let. J The fcarlet dyed with 
 Lac is lefs beautiful than that with Cochi- 
 neal, but of greater folidity. Mr. Hellot 
 obferves that when employed in fubftance, 
 the refinous matter of the Lac is apt to melt 
 in the hot liquor, and ftain the cloth ; and 
 hence directs the colouring fubfiance to be 
 previoufly feparated in the form of lake. 
 
 For thispurpofe, half a dram ol powdered 
 Comfry root is to be boiled in a quart of 
 water for a quarter of an hour ; and fome 
 powdered Gum Lac digefted in the decoc- 
 tion for-two hours : The tindlure appears of 
 a fine crimfon colour, and the remaining; 
 Gum (if the quantity of liquor has been 
 fufficient to extradf all its tinging matter) of 
 a pale ftraw colour. The tindture being 
 poured off clear, and a folution of Alum 
 gradually added to it, the colouring matter 
 fubfides, and the liquor remains colourlefs ; 
 
 333 
 
 Wax. 
 
 -V— — J> 
 
334 Vegetable Juices. 
 
 Lacca, maining matter is dried, and fold under the name of Lacca in grants or Seed- 
 
 u— v— . lac. The Stick-lac, melted over a gentle fire, and poured off from its impu- 
 rities upon a Marble, forms dark-coloured cakes in appearance like Glafs 
 of Antimony, called Lacca in tabulis or Shell-lac. This laft fort is the deareft 
 of the three, and uled chiefly in Sealing-wax. The Lac moft common in the 
 German fhops is the Seed-lac, which generally has had a part of its colour ex- 
 tracted. This is in fmall tranfparent pieces, like little Garnet (tones. Its 
 goodnefs is in proportion to its dark-brownifh red colour ; but it is never equal 
 to the Stick kind. Befides being of a red colour in the mafs, it ought to tinge 
 the fpittle of a purple red. 
 
 Chemical ex- Gum lac may be looked upon as a very hard fort of Wax, tinctured with an 
 
 animation, animal red of the Cochineal kind. The beft Stick-lac, or the part which lies 
 next to the wood, and which is moft impregnated with infeds and with colour, 
 yields in burning a degree of ftench like that of animal matters. 1'he Seed- 
 lac does not diffolve in water, nor in oils. I have digefted it with a confider- 
 able heat both in exprefted Oils, as that of Almonds, and in fundry diftilled 
 ones, as thofe of Anifeeds, Turpentine and Thyme, without being able to 
 obtain any other than a dilute tindure : The Oil of Thyme extraded moft. 
 I digefted it alfo, with a heat raifed to ebullition, in water acidulated with the 
 Spirits of Vitriol, of Nitre, and of Sea- fait, and in diftilled Vinegar ; and with 
 thefe alfo obtained only dilute tindures : That with the nitrous acid was the 
 paleft. To Alum-water, it gave a beautiful tranfparent red. Alcaline Salts 
 extraded more than the acidulated liquors, the tindure being thick, and of a 
 quite dark violet-purplifh red : The quantity diflolved, however, was but 
 fmall. Of the concentrated mineral acids, the vitriolic extraded exceeding 
 little, the marine fomewhat more, and the nitrous nothing : This laft not only 
 acquired no colour itfelf, but deftroyed that of the Lac, rendering it of a quite 
 pale yellow. Spirit of Wine feems at firft to have little adion on Lac, ex- 
 trading only a moderate tindure but by perfeverance I have made it diffolve 
 at length nearly the whole: From fixteen ounces of Lac I obtained fifteen of 
 fpirituous extrad. The folution is not red but of a brown colour : It does not 
 pafs through a filter, looks like a thick Mucilage, and does not eafily part 
 with the fpirit. The fame quantity of Lac, treated firft with water, yielded one 
 ounce and fix drams of extrad; after which, it gave out to redified fpirit 
 fourteen ounces. Sixteen ounces of Seed-lac, diftilled in an open fire, yielded 
 nine ounces and fix drams of a Butter or thick empyreumatic Oil, fimilar to 
 that of common Wax ; after which arofe one ounce and fix drams of a watery 
 liquor not manifeftly acid or alcaline : The refiduum weighed two ounces and 
 a half. 
 
 Lac was formerly an ingredient in fome officinal compofitions •, and in many 
 difpenfatories, a tindure of it in Alum-water is ftill retained. It feems to be 
 an article that medicine can very well fpare, as it contains nothing of any re- 
 markable adivity. Its principal ufe is as a colouring drug, and for Sealing- 
 wax: Thofe who employ it in varniflies, gain from it but little, if managed 
 according to the common receipts. 
 
 SECT. 
 
[ 335 31 
 
 SECT, III. 
 
 Of Plants or their Parts in fubjlance . 
 
 CLASS I. 
 
 GUMMY VEGETABLES. 
 
 F the plants whofe prevailing principle is a gummy or mucilaginous fub- Gummy 
 { lance, Marfhmallow and Comfry are the chief. We may obferve in y EGETABIES ; 
 both thefe plants, what obtains but in few, that the roots, leaves, and _ — 
 feeds, agree in their chemical compofition, and differ only in the quantity of 
 Mucilage they afford, the roots yielding confiderably more than any of the 
 other parts. They contain alfo a refinous matter ; but the Gum is neverthe- 
 lefs their charadleriflic, as the Refin has no particular tafle or fmell, nor the 
 plant any medicinal activity but what refides in its Gum. As both plants are 
 inodorous and infipid, they give over nothing, or nothing confiderable in di- 
 ilillation, either with water or. with fpirit. 
 
 THE MARSHMALLOW is called AUhaa, as fome fuppofe from its j 
 healing quality (a.\Qcavu, Sano -,) Bifmalva , Malvavifcus , Ibifcus , Evifcum , from jyj A R s H -_. 
 itsvifcofity, and from its having twice the power of the common Mallow. The MALLOW> 
 fpecies here intended is that which Cafpar Bauhine diflinguifhes by the name of < » 
 
 Althea diofcoridis & plinii : It grows wild in watery places, though cultivated 
 alfo in gardens. The root is pretty long, about the thicknefs of the finger, 
 brown on the outfide, and white within. 
 
 Two ounces of the dry root yielded with water, ten drams fifty grains of 
 mucilaginous extract ; and afterwards with fpirit forty-one grains of Refin. 
 
 The fame quantity, treated firfl with fpirit, gave fix drams of a refinous ex- 
 trad (a), a confiderable portion of the Mucilage diffolving in that menflruum 
 along with the Refin : The remainder, boiled in water, gave out five drams 
 and forty-eight grains of pure Mucilage. 
 
 From two ounces of the dry leaves were obtained, by water, five drams and 
 two fcruples of mucilaginous extract ; and afterwards by fpirit, three drams 
 thirty- three grains of a refinous one. From the fame quantity, treated firfl 
 with fpirit, and then with water, were gained four drams two fcruples of a 
 
 refinous 
 
 fpirit, I obtained but two drams : The ex- 
 tract had more of a fweetifh take than that' 
 made with water ; together with the light! 
 fmell obfervable in the root itfelf. 
 
 (a) Six drams of refinous extrail. ] I have 
 not obferved the quantity of refinous matter 
 to be fo large as in the author’s experi- 
 ment. From two ounces of Marfhmallow 
 toot, digefled and boiled in frefh parcels of 
 
336 Plants and their P a r t s. 
 
 Mars h- refinous mafs, and afterwards three drams thirty-eight grains of Mucilage- — ~ 
 mallow. The indilfoluble earthy matter amounts in the roots to fomewhat more than 
 c. ,, — — ) one fourth, and in the leaves to about one half of their weight. 
 
 jl, COM FRY, from the extraordinary power of confolidating wounds for- 
 
 Co mfry. merly afcribed to it, has received the names of Confolida , Solidago , and Symphy- 
 
 %. — ; turn. The officinal fpecies is that which bears purple flowers, called Male 
 
 Comfry, Symphytum flore pur pure o qua mas , C. B: It grows wild in moift fields 
 and meadows. The root is about an inch thick, black on the outfide, and 
 white within. 
 
 From two ounces of the dry root were obtained by water, twelve drams of 
 gummy extrad ; and afterwards by fpirit, eight grains of Relin. It was pretty 
 remarkable, that on digefting the gummy extrad in redified fpirit, near one 
 half of it diffolved ; and that it was not made tenacious or cohefive by the fpi- 
 rituous liquor, but continued powdery. Two ounces of the root, treated 
 with redtified fpirit at firft, gave four drams of refinous extradt, and afterwards 
 with water, nine drams of Mucilage. 
 
 Thefe plants are employed medicinally as emollients and incraflants, exter- 
 nally as well as internally ; in plafters, falves and ointments ; in infufions for 
 chapt lips, and other like complaints ; and by fome of the French oculifts for 
 diforders of the eyes. The Marflimallow root, boiled with Red-faunders, or 
 in red Wine, and afterwards dried,, is ufed as a dentifrice, under the name of 
 French Althaea. 
 
 III. the feeds of Fenugreek may be referred to this clafs, their prevail- 
 Fenugreek. ing principle being a mucilaginous matter : They are fometimes ufed as an 
 v— — ' emollient in external applications, but chiefly againft coughs and other like 
 diforders in cattle. The plant ( Fanum gracum fativum , C. B.) is in fome places 
 fown in fields : It has a papilionaceous flower, and produces its feed in pods. 
 
 The feeds are of an oblong flattiffi quadrangular figure, rounded at one end, 
 covered with a yellowifh fkin, which acquires a darker reddifh or brownilh co- 
 lour by age; internally of a very pale yellow ; of a fweetifh but not agreeable 
 fmell ; and an unpleafant, bitterifh, flimy tafte. They contain a portion of 
 expreffible Oil, intimately blended with the refinous and mucilaginous prin- 
 ciples ; by the mediation of the firft of which the Oil is extracted by Spirit of 
 Wine, though it in great meafure feparates afterwards during the evaporation 
 of the tindure. 
 
 Sixteen ounces of the feeds yielded with water eleven drams and a fcruple of 
 a mucilaginous fomewhat bitterifh extrad ; and afterwards with fpirit, half a 
 dram of an unduous Refin. On applying fpirit at firft, I obtained from the 
 fame quantity, four drams and a half of a very ungrateful refinous extrad; 
 after which, water took up fix drams and a half of Mucilage. The diftiiled 
 water fmells a little of the Fenugreek, but gives no appearance of any eflentiai 
 Oil : It foon lofes the fpecific flavour of the feeds, but continues ungrateful. 
 
 CLASS 
 
P l a n t s and their Parts* 
 
 337 
 
 Resinous 
 
 Vegetables. 
 
 CLASS II. 
 
 RESINOUS VEGETABLES. 
 
 ESINOUS VEGETABLES are thole, whole diflinguifhing tafle, 
 medicinal adfivity, or colour, refide in their Refin; and which do not 
 contain Gum or Mucilage enough, to render any confiderable quantity of the 
 Refin foluble by infufion or digeftion in water. By ftrong coftion in water, 
 great part of the Refin may often indeed be melted out ; but even in this cafe, 
 it is far lefs perfectly extracted than by moderate digeftion in rectified fpirit. 
 
 The fubftances of this clafs have little or no fmell, and give over little or no- 
 thing, in diftillation, with water or with fpirit. 
 
 Gums or Mucilages are in all plants nearly the fame ; but Refins differ ex- 
 tremely from one another. The infipid and inactive Redfaunders; the aftrin- 
 gent and bitter Peruvian Bark ; the pungent Guaiacum and Pimpinella ; the 
 more acrid Pellitory and Stavefacre ; the purgative Jalap, Turpeth, Mattalifta, 
 Hermodadtyl ; the emetic Ipecacoana and Alarum ; the more violent Bryony, 
 
 Agaric, Colocynth, Hellebore; and the deleterious Coccognidia, Cocculus 
 Indus, Nux vomica, and Faba fandli Ignatii, owe their qualities to their refi- 
 nous principle. 
 
 RED-SAUNDERS is a hard, compad, ponderous wood, of a dark Red-Saun- 
 blackifh-red on the outfide, and alight red colour within; of no particular df.rs. 
 fmell or tafte. It is brought from the Coromandel coaft, and from Golconda : 
 
 Of the tree we have no certain account. Its principal ufe is as a colouring drug. 
 
 Thofe whofe bufinefs it is to rafp and grind it into powder, probably employ 
 certain faline or other additions to improve the colour ; whence the remarkable 
 differences in the colour of powdered Saunders prepared in different places : 
 
 That of Stralburg is of the deepeft and livelieft red : Some forts are of a dead, 
 dark red, and fome of a pale brick red ; fome incline to purple or violet, and 
 fome to brown. 
 
 The colour of this wood refides wholly in its Refin, and hence is extra&ed 
 by rectified fpirit, whilft water, though it takes up a portion of mucilaginous 
 matter gains no tinge, or only a flight yellowifh one (£). From two ounces of 
 
 the 
 
 (b) Gives no red colour to water.] This 
 property readily diftinguilhes Red-faunders 
 from Brazil-wood, which fome have con- 
 founded with it ; that wood communicating 
 its red colour to water as well as to fpirit. 
 
 ALKANE T ROOT. 
 
 ' H E roots of Alkanet agree in the above 
 refpedf with Saunders-wood, but differ 
 from it remarkably in others. They im- 
 part an elegant deep red to pure Spirit of 
 
 X 
 
 Wine, to Oils, to Wax, and to all undlu- 
 ous fubftances : I do not know of any red 
 drug that tinges Oil of fo fine a colour. To 
 water, they give only a dull browniftr. 
 The fpirituous tindfure, on being infpiffated 
 to the confiftence of an extradt, inftead of 
 preferving its fine red, like that of Saunders, 
 changes to an unfightly brown. Volatile 
 fpirits have been faid to gain from this root 
 a beautiful violet or amethyft colour ; but 1 
 have not found, that they extradt any other 
 than a dull reddifh brown. 
 
 The 
 
Plants and their Parts. 
 
 N-ths wood were obtained by Spirit of Wine, three drams and a half of refinous- 
 extract; and afterwards by water, a fcruple of Mucilage. By applying water 
 at firft, I obtained from two ounces, two drams and fix grains of a tough 
 mucilaginous extract, which could not eafily be reduced to drynefs : The re- 
 mainder ftill yielded with fpirit, two drams of Re fin. The indiffoluble mat- 
 ter weighed in the firft cafe, an ounce and a half and fifteen grains ; ia the 
 latter, nineteen grains lefs. Neither the diftilled water nor fpirit had any re- 
 markable tafte or fmell. 
 
 The red colour of Saunders appears to be no other than a concentrated yel- 
 low, for by bare dilution it becomes yellow: A grain of the refinous extract, 
 didblved in an ounce of re&ified fpirit, tinges it red ; but this folution mixed 
 with a quart of frelh fpirit, gives only a yellow hue. Hoffman reports that 
 th is Refin does not give a tinbture to any kind of Oil : 1 have tried five Oils,, 
 thofe of Amber, Turpentine, Almonds, Anifeeds and Lavender : It gave no 
 colour to the two firft, but a deep red to the laft, and a paler red to the 
 other two. 
 
 U PERUVIAN-B ARK, Cortex Peruvianas, called, from its efficacy 
 
 Peruvian- againft intermitting fevers, Febrifugum peruvianum , cortex antifebrilis and anti- 
 IJark. quar tilts and from a cure performed by it on the Lady of Count del Cinchon 
 
 Viceroy of Peru, Cortex China china or Chin china, Kinkina , Quinquina, Conn- 
 tijfa, &c. was firft brought into Europe, in the year 1649, by Cardinal de Lugo, 
 who was then the Spanifh Viceroy in the Weft-Indies. It continued for lb me 
 time a very lucrative fecret in the hands of the Jefuits,. who reduced it into 
 powder the better to difguife it, and fold it for its weight in Gold ■, whence its 
 names Pulvis jejmticus, Pulvis patrum, Pulvis Cardinalis de Lugo. 
 
 The tree, called by Ray, Arbor febrifuga Peruviana, China china, & quinquina, 
 & gannaperide dibia, is plentiful on the hills near the city Loxa in the province 
 of Quito in Peru. It is faid, that the trees which grow at the bottom of the 
 hills, have the thickeft bark, fmooth and whitifh on the outfide, clear or yel- 
 lowiffi-brown within, the lead bitter, and of the leaft virtue ; that the bark of 
 
 thofe 
 
 The Alkanet plant is a fpecies of Bu- 
 glofs, named by Tournefort BughJJinn radice 
 rubra, five anchuja vulgatior floribus camlets. 
 It is a native of the warmer parts of Europe, 
 and cultivated in fome of our gardens : The 
 greatefr quantities are raifed in Germany 
 and France, particularly about Montpelier, 
 from whence we are chiefly fupplied with 
 the roots. 
 
 The Alkanet root produced in England 
 is much inferior in colour to that brought 
 from abroad ; the former being only lightly 
 reddifh, the latter of a deep, purplifh red. 
 This has induced fome to fufpecl, that the 
 foreign roots owe paft of their colour to 
 art ; but a chemical examination teaches 
 ©therwife. The colouring matter is found, 
 upon experiment, to be of the fame kind in 
 
 both, and to differ in feveral of its proper- 
 ties from that of all the other known red 
 drugs ; fo that no artifice appears to be 
 practicable without difcovery, unlefs it was 
 concentrating the colour of two roots into= 
 one, or fuperfaturating one root with the 
 colour extracted from another. 
 
 The principal ufe of Alkanet root is for- 
 colouring oils, unguents, lip falves, plafters, 
 &c. Wax tinged with it, applied on warm 
 Marble, ftains it of a flefh colour, which 
 finks deep into the ftone :■ 'The fpirituous 
 tindture gives a deep red ftain. 
 
 The colour of this root is confined to the- 
 cortical part, the pith being whitifh : 
 Hence, as the fmall roots have more bark* 
 in proportion to their bulk,, than the large 
 ones* thofe alfo contain rnoft colour. 
 
Plants and their P a r t s* 339 
 
 thofe on the top is fomewhat bitterer, thin, full of protuberancies, of a blackifhftARuviAN 
 colour on the outfide, and of a dark brown within : That thofe produced Bark. 
 about the middle height yield the bittereft and heft bark, not fo fmooth and 
 pale coloured as the one, nor fo rugged and dark coloured as the other. Vail- 
 Jant, a celebrated botaniil of Paris, afiured me that he knew fix forts •, and 
 confirmed the account given by Lemery and Pomet, that Potofi affords the 
 bed •, that this is much browner, bitterer, more aromatic and more pungent, 
 than the Bark of Quito. But our bufinefs is to chufe the belt of what is 
 brought to us. This is externally of a blackifh brown, and internally of a 
 dark cinnamon colour, fomewhat unequal on the furface, compact, firm, and 
 not eafy to break, of a moderately bitter aftringent take, with a mixed kind of 
 aromatic and mufly flavour. The large thick pieces are feidom good : Thofe 
 which are rolled up into quills like Cinnamon, are apt to have foreign matters 
 lodged within, and therefore fhould be broke and examined before we pulve- 
 rize them for ufe. 
 
 Mr. Boulduc obtained, from a pound of Bark, only five drams and afcrupie 
 of ipirituous extrad : In my experiments, a pound yielded, with redified fpirit, 
 ten drams and two fcruples of refinous, and afterwards with Water, five drams 
 of gummy extrad : On applying Water at firft, I obtained feven drams and 
 a fcruple of gummy, and afterwards by fpirit, fix drams of refinous extrad. 
 
 Thefe experiments fhew a remarkable difference betwixt Peruvian- bark and 
 Cafcarilla, which is fuppofed to be of the fame kind : From a pound of Peru- 
 vian-bark we obtain at moft but two ounces and five fcruples of extrad, rec- 
 koning the gummy and refinous together (x) ; whilft a pound of Cafcarilla 
 yields upwards of feven ounces and a half : The latter contains alfo an effen- 
 tial Oil, of which we difcover nothing in the former. The extrad made from 
 Bark by applying Water at firft, taftes confiderably bitter and aftringent, but 
 not near fo much fo as that made by fpirit- — -The principal ufe of this Bark 
 is in the diforder againft which it was at firfl introduced, intermitting-fevers : 
 
 It is given to half a dram and upwards, every fourth hour during the inter- 
 mifiion, in conjundion with Sal ammoniac or vitriolated Tartar, which prevent 
 its occafioning the ill confequences that it is apt to do by itfelf. 
 
 GUAIA- 
 
 (x) Quantity of extract. ] Different forts 
 of Peruvian-bark differ confiderably in their 
 yield of extrad. Thofe which I examined 
 afforded a much larger quantity of refinous 
 extrad than the author obtained from 
 his. 
 
 It is obfervable of this drug, that its 
 aftringency relid es wholly in its Refin, 
 which does not appear to be in any degree 
 foluble in watery liquors ; but its bitternefs 
 in a gummy-refinous fubflance, or fuch an 
 one as is diffoluble both in Water and in 
 Spirit. Both principles may be extraded 
 
 by boiling in Water ; the Refin melting 
 out by the heat, and rendering the liquor 
 turbid : The decodion, in this ftate, taftes 
 aftringent as well as bitter, but on ftanding 
 it depofites the Refin and becomes clear, 
 and then proves (imply bitter. Repeated 
 codion and large quantities of Water are 
 neceffary for extrading all the virtues of the 
 Bark : The Refin melts out in the firft 
 boilings; the decodions made afterwards 
 are tranfparent and bitter, without the lead 
 turbidnefs or aftringency. 
 
 
34 ° 
 
 Plants and their Parts, 
 
 III. 
 
 Guaiacum 
 
 Wood, 
 
 G U A I A C U M, Lignum guaiacum , guaiacan , benediflum , fanBum, vit^e^ 
 Palus fanftus , Palma fanBa , is the wood of two kinds of trees growing in 
 America, called by Plukenet, the one Guaiacum Jamaicenfe , &c. the Ja- 
 maica Guaiacum-tree, with bright green roundilh leaves like thofe of the 
 Maple ; the other Euonymo adfinis occidentalism &c. an occidental nut-bearing 
 tree, allied to the Euonymus or Spindle-tree, with winged leaves like thofe 
 of butcher’s broom, and a fungous bark at the joints. The wood comes over 
 in large pieces, weighing four, five and more hundred weight, from Jamaica, 
 Mexico, Porto-rico, Borigue, St. Domingo, and other parts of the Weft 
 Indies : The tree has been raifed alfo in Europe, but proved far inferior in 
 quality to that produced in its native climate, and yielded nothing of the refi- 
 nous juice which it plentifully bleeds there. (See page 298.) 
 
 This wood is remarkably hard, compad, and fo heavy as to fink in Water; 
 of a brown, or yellowilh brown colour, often blackifh, or marbled as it were 
 with different colours : When the tree is ftanding or newly felled, the bark 
 adheres fo firmly as not to be got off even with iron tools ; after lying for 
 fome time it feparates eafily. On account of its great hardnefs, folidity, and 
 indifpofition to crack, it is employed by the turners and otners for feveral of 
 
 the more curious mechanic ufes.« In Holland, at Hamburg and other 
 
 places of large commerce, it is rafped in workhoufes eftablifhed for that pur- 
 pofe, after the fame manner as the Colouring- woods ; and from thefe the 
 druggift and apothecary are fupplied. 
 
 Guaiacum is a very refinous Wood : On expofing it to a moderate heat, 
 the Refin vifibly melts out. By digeftion in highly redified Spirit of Wine, 
 1 obtained three ounces and a half of refinous extrad from fixreen ounces of 
 the Wood: Such as had been boiled in Water till that menftruum would take 
 up no more, yielded ftill, with redified Spirit, two ounces of Refin upon 
 the pound. Water applied at firft extrads an ounce and a half, and after 
 fpirit has performed its office half an ounce and two fcruples, of gummy 
 matter. The indiffoluble part, when the gum was extraded firft, weighed 
 twelve ounces and a half ; when the Refill was firft extraded, only twelve 
 ounces and two drams. Thefe experiment^ were made with chips of a good 
 refinous kind of Guaiacum : The rafped Wood commonly fold yields lefs of a 
 refinous and more of a gummy extrad. From a pound of good rafpings 1 
 obtained by Spirit two ounces and fix drams, and afterwards by Water one 
 •ounce : Another pound of the fame, treated with Water at firft, gave two 
 ounces, and afterwards with Spirit one ounce and fix drams. 
 
 A ftrong decodion of Guaiacum is ufed as an alterative diet-drink in vene- 
 real, cancerous, and other diforders from an impurity of the blood and ja ces. 
 Hoffman recommends the fpirituous extrad (which is the moft adive prepara- 
 tion) as a high antidote againft the venereal pollen, provided it be ufed pro- 
 perly according to the laws of medicine. He mentions alfo another refinous 
 preparation of this Wood, under the title of “ A fingular Refin, of a ftimu- 
 “ lating errhine quality, and poffeffing alfo a corroborating power, highly 
 
 friendly to the nervous parts of the head : ” This, according to his ac- 
 count. 
 
Plants and their P a r t s. 341 
 
 count, is the Refin that precipitates in boiling down a watery decodlion of the Guaiacum 
 Wood. l, -“ 1 
 
 A pound of Guaiacum Wood, diftilied in an open fire, gave three ounces 
 and a half of Spirit, and one and a half of empyreumatic Oil. Some report, 
 that the fpirit is of the neutral kind *, that it makes no effervefcence either 
 with alcalies or with acids, and that it forms an ink with Vitriol : I have ob- 
 fervea, that it does effervefce conftantly with alcalies, though not very 
 ffrongly, on account of its oily matter which fheathes the acidity ; and that 
 with Vitriol it ftrikes a blackifh brown colour, but by no means an inky 
 biacknefs. I have not found that a decodlion of the Wood changes Syrup of 
 Violets red, as fome relate that it does ; nor that the Wood imthe mafs, in 
 chips, or in rafpings, heated by itfelf or with Oil, would take fire on the affu- 
 fion of Oil of Vitriol, or of a mixture of Oil of Vitriol with Nitre or its com 
 centrated Spirit. 
 
 Of the Bark of Guaiacum, there are two kinds, one fmooth, the other Bar k’ 
 unequal on the furface : The former is faicl to be the Bark of the firft of the 
 trees above-mentioned, the other of the fecond. Some confine the name 
 Guaiacum to the Wood and Bark of the firft fort, and that of Sandium to the 
 latter •, but there is no remarkable difference betwixt the two. Greateft part 
 of the Bark that comes to us is moderately fmooth ; externally of a dark 
 grey colour, with blackifh yellow and greenifh fpecks, internally yellowifh, 
 reddifh or brownifh ; compofed of plates or a number of thinner rinds applied 
 iucceffively upon one another ; compact and heavy ; of a bitterifh difagreeable 
 tafte. 
 
 Eight ounces yielded one ounce and four fcruples or refinous extradl, and 
 afterwards five drams and one fcruple of a gummy one. The fame quantity, 
 treated firft with Water and then with Spirit, gave ten drams one fcruple of 
 gummy, and four drams of refinous extradr, The indiffoluble part weighed, 
 in both, cafes, fix ounces and two drams. 
 
 PI M PINE'LL A, or Bipennula^ fuppofed to be fo called from its leaves IV. 
 Handing in double rows like feathers,, is an umbelliferous plant, growing wild Burnet 
 in dry, landy, gravelly grounds. The fpecies diredled for medicinal ufe is the^ AXIFRAGB 
 Pimpinella Saxifraga major umbella Candida. C. B. or greater Burnet Saxifrage 
 with white flowers; but we may take promifcuoufiy the roots of the fmaller 
 forts, provided they are not produced in moift rich foils : One and the fame 
 fpecies differs more in different foils, than different fpecies do in one foil. The 
 roots are of a pale yellowifh colour, about the thicknefs of the little finger ac 
 molt, of a peculiar fmell, and an acrid burning tafte. 
 
 This root contains a portion of effential Oil : On diftilling a large quantity 
 with Water, the diftilied liquor is not only impregnated with its flavour, but 
 fome particles of ablual Oil may be diftinguifhed ; much too inconfiderable 
 however to entitle the plant to a place among the oily ones. The pungency 
 and diftingmfhing tafte or the Pimpinella refide wholly in its Refin : What 
 Water extradcs, dilcovers only a fweetifh tafte, with no remarkable pun- 
 gency.. 
 
 Two 
 
34 2 Plants and their Parts, 
 
 PiMprNEL. Two ounces of ther root, cut in pieces, yielded, with Water, fix drams and 
 — • ' a fcruple of gummy extrad ; and afterwards, with Spirit, only two fcruples 
 of a refinous one; this lad was in tafte extremely naufeous. Two ounces more, 
 treated firft with Spirit, gave four drams of refinous extract; and afterwards 
 with Water two drams two fcruples of an infipid and inodorous gum. It is 
 oblervable, that the fpirituous extract is in tafte far more difagreeable than 
 the tincture, and impreffes a particular difguftful oilynefs. In effed this root 
 contains a grofs oily matter, of the expreffible kind ; which redified fpirit 
 extradts along with the Refin, and which in the tindture is diluted and con- 
 cealed by the fpirit, but leparates and difcovers itfeif on drawing off the 
 menftruum. A faturated tindture or effence is therefore the befc preparation 
 of Pimpinella. 
 
 This root is a powerful refolvent and aperient medicine : It promotes per- 
 fpiration and urine, purifies the blood and juices, and proves remarkably 
 ferviceable in diforders of the fauces, catarrhs, infardtions of the brealt by 
 vifcid phlegm, obftrudtions of the vifcera, and the confequences of ill ma- 
 naged mercurial falivations. A mixture of the eflence with Syrup of Violets, 
 ora tea-fpoonful of the effence by itfeif, is a common medicine, in Germany, 
 for fore throats. 
 
 V. PELLITORY, called from the fiery tafte of its root Pyrethrum , is a 
 Pellitory. plant with Fennel like leaves, and a flower like that of the common purplifh 
 v— — daily : Hence it is named by Cafpar Bauhine Pyrethrum ficre hellidis . It is 
 generally faid to be an oriental plant : Pomet relates that it grows plentifully 
 about Tunis, and that the Pellitory ufed in France is imported from thence by 
 the way of Marfeilles. Some report that it is found on the hills of Switzer- 
 land and Italy ; but of this I find no account in the Italian botanifts : Nor in- 
 deed is the plant defcribed by any of the modern botanifts 1 know'- of. Thus 
 much is certain, that it does not grow in thedutchy of Magdeburg, as Schurt- 
 zius and others affirm. We find there a fpecies of Pharmica whofe roots are 
 called by fome Pellitory, and ufed like it as a Mafticatory ; but none of the 
 true Pyrethrum. 
 
 Pellitory roots are fold in bundles, tied up with ftrong twigs : They are 
 feldom fo thick as the little finger, and have generally a piece of the woody 
 ftalk at the head : The bell; are dry, compad, of a brown colour, not eafy to 
 cut with a knife. The charaderiftic property of this root is its hot burning 
 tafte, which refides not in a faline matter, as Lemery, Juncker and others 
 affirm, but wholly in a refinous one ; water extrading a little of it, but redified 
 fpirit the whole. It is obfervable, that notwithftanding the extreme acrimony 
 of this root, the quantity of matter on which that quality depends, is very 
 fmall, fcarcely amounting to a lcruple in an ounce. 
 
 Two ounces of the root, treated with redified fpirit, gave no more than two 
 fcruples ofextrad, in which, as in other extrads made by fpirit at firft, a por- 
 tion of gummy matter was retained along with the Refin ; the refiduum digefted 
 with water, gave nine drams and a half of gummy extrad, fix drams, all but 
 twelve grains remaining undiffolved. On inverting the procedure, and apply- 
 ing water at firft, I obtained from the fame quantity of Pellitory, ten drams of 
 
 gummy 
 
Plants and their Parts. 343 
 
 gummy extract, and afterwards by fpirit only onefcruple ofRefin, the undlf- Pellitory. 
 l'olved part weighing five drams thirty-feven grains. 
 
 Both the fpirituous extracts were exceflively fiery ; that made after water did 
 not difcover its fierynefs in the mouth fo foon as the other, as being more purely 
 refinuus, and confequently more difficultly acted upon by the Saliva, on ac- 
 count of the previous- feparation of the gummy parts by the water. The watery 
 extracts could fcarce be reduced into an uniform coherent mafs, being difpoled 
 rather to a crumbly or powdery confiftence. Water diftilled over irom the 
 root, elevated a little of its acrid matter, perceptible upon keeping the liquor 
 for fome time in the mouth. 
 
 The principal ufe of this root is as a mafticatory in paralytic and lethargic 
 diforders, particularly in palfies of the tongue, and in toothachs, either by it- 
 felf, or made into troches with other fubflances, and as an ingredient in ftimu- 
 lating cataplafms. It is fometimes likewife given internally, for heating, fti- 
 mulating, ffrengthening the ftomach, and diffolving vifcid phlegm. The 
 Vinegar- makers employ it for making their Vinegar fharper. 
 
 STAVE SAC RE, Staphifagria, is referred by fome botaniffs, from its VI. 
 dowers, to the genus of Larkfpurs ; by others, from its feeds, to that of Aco- Stavesacse, 
 nites. Tournefort calls it “ Larkfpur with leaves like thofe of the Plane-tree ^ 
 
 and Plukenet the burning Aconite, with leaves almoft like thofe of Ricinus, 
 
 “ and a large blue flower.” It is a native of the fouthern parts of France, of 
 Italy and Spain, particularly Apulia and Calabria ; but the greateft quantities 
 are met with in Dalmatia and Iflria : It loves fhady places. 
 
 The part made ufe of is the feeds, of which four, five, or fix are commonly, 
 joined together in one cod, fo as to appear one roundifh kernel. The Tingle 
 feeds are of an oblong, irregularly triangular figure: Two of the fides, by 
 which each feed had been joined to two others, are fiat •, the third, contiguous 
 to the cod, is rounded. They are covered on all fides with a rough rugged 
 membrane, which when perfectly ripe is of a brown colour : Under this lies 
 another thin fkin, which indoles a white kernel, of a difagreeable, bitterifh, 
 hot tafte : By age, the kernel becomes yellow and brownifh. 
 
 Thefe feeds are employed chiefly in ointments for deftroying cutaneous in- 
 iedls, whence their nam t Grana pedicularia and as a mafticatory for tooth- 
 achs, CT. Taken internally, they operate with violence both upwards and 
 downwards : The ancients ventured on their internal ufe, and I have myfelf 
 
 feen them given in Poland but the practice is by no means to be followed. 
 
 Even when applied externally, they have been productive of dangerous confe- 
 quences, of no lefs than the epilepfy. Simon Paulli and others obferve that 
 they have a firangulatory quality : And profeffor Schulze relates, that his- 
 fenles were difordered by chewing fome of them for a toothach. Thus much is 
 obvious to the tafte, that they have a naufeous burning heat and acrimony, 
 which refiaes rather in the kernel than in the fhell. 
 
 An ounce of the feeds reduced into powder, yielded with rectified fpirit two 
 fcruples and five grains of refinGus extract : In this procefs, a grofs Oil of the 
 exprefilble kind, feparated, to the quantity of a dram and a half : The matter 
 Eft by fpirit, digefted and boiled with water, gave two fcruples four grains of 
 a gummy 
 
34*4 Plants and their Par t s. 
 
 staves A cre., g Umm y extra#, near five drams remaining at laft undiflolved. Another 
 ounce, treated firft with water, yielded one dram and thirty-five grains of 
 gummy extra# ; and afterwards with fpiric, one dram and eleven grains of 
 grofs Oil, but no more than a fingle grain of Refin : The indiflbluble refiduum 
 weighed five drams nine grains. As the watery extra# retains great part of the 
 Refin, it proves confiderably acrid, though far lefs fo than the fpirituous : The 
 extra# made by water after fpirit has performed its office, difcovers no acri- 
 mony. In diftillation, fpirit brings over nothing*, the diftilled water taftes 
 fomewhat difagreeably. 
 
 VIL COCCOGNIDIUM or Gramm cnidium is the berry of a fhrub, grow- 
 G r a n a ing wild in Germany in moift fiiady woods, called by an Arabic name Mezereon * 
 C n 1 d i a. and from its leaves bearing fome refemblance to thofe of the Bay and of the 
 Olive-trees, Laureola and CbameL-ea. The Ipecies which produces theCoccog- 
 nidia is named by Cafpar Bauhine Laureola folio deciduo, flore purpureo, ojficinis 
 Laureola femina. The flowers come forth early in the fpring before the leaves j 
 they are /mail, monopetalous, fhaped fomewhat like a funnel, of a pale pur- 
 plilh-red colour, and an agreeable fmeil, whilft all the other parts of the plant 
 are difagreeable. The leaves, which follow the flowers, are foft, of a paie green 
 colour, without any gloffinefs. The (talks and branches are very flexible, co- 
 vered with two barks ; the outermoft of which is of an afh-colour, thin, and 
 eafily peeled off-, the innermoft green on the outfide, white within, very tough, 
 
 and hard to tear The berries are at firft green, afterwards red, and when 
 
 ripe of a brown colour: They are much about the fize, and partly of the ap- 
 pearance of Pepper-corns : They contain under the outward brown fkin, ano- 
 
 ther thin fmooth one, commonly greenifh and glofly^ and under this a third, 
 which looks as if coated with black varnifh : Under this lies the kernel, of a 
 white colour, and about the fize of a grain of Hemp-feed. 
 
 The leaves and the bark were formerly ufea as purgatives, but have long 
 been juftly laid afide on account of the violence of their operation : The cor- 
 rection of them by maceration in Vinegar or Milk is infignificant. The berries 
 are in a high degree virulent : The kernels, applied externally, inflame and 
 exulcerate the fkin ; chewed, they difcover little tafte at firft, but in a ffiort 
 time begin to burn the mouth like a coal fwallowed, they occafion immenfe 
 vomitings and purgings, inflammations of the bowels, and even death. As 
 experience has fully evinced their deleterious qualities, it is furprizing that any 
 medical writer fliould recommend them ; and yet we find both the berries in 
 fubftance, and a watery extra# made from them, dire#ed as an evacuant in 
 dropfies : Though the extra# is more a#ive than the berry itfeif, Herman re- 
 commends half a dram of it for a mild medicine. 
 
 With regard to the chemical compofition of this fruit, it contains, befides its 
 cauftic Refin, and a gummy matter, a conliderable portion of an expreffible 
 Oil. The Oil is of itielf mild and infipid as the other Oils of that clafs ; but as 
 thefe kinds of Oils are menftrua for Refins, it retains, in mod of the proceffes 
 by which it is feparated, fo much of the Refin, or of its more fubtile parts, as to 
 prove highly acrimonious : Half a grain of the refinous extra# gives a fiery tafte 
 to half an ounce of infipid Oil. From four ounces of the berries I obtained by 
 
 expreffion 
 
Plants a?td their Parts, 34,^ 
 
 expreffion half an ounce of Oil, confiderably acrid. An ounce of the berries, Grana 
 boiled with water, gave five fcruples feventeen grains of extra#; and five C n i d i a. 
 fcruples and a half of a milder Oil, which feparated in the operation : The re- v~ — 
 
 mainder, treated with fpirit, gave two fcruples of Refin. Another ounce di- 
 gefled at firft with fpirit, yielded four fcruples and eight grains of a refinous 
 mafs, after which water extracted two fcruples thirteen grains of infipid Mu- 
 cilage. 
 
 It is obfervable, that though grofs Oils are not of themfelves foluble in Spirit 
 of Wine, yet the Oil is here fo intimately combined with the other principles, 
 as to be extracted by the fpirit, and remain uniformly mixed till great part of 
 the menftruum is evaporated; the grofier Refin then feparates and falls to the 
 bottom, and the fluid Oil, ftrongly impregnated with the more lubtile cauftic 
 matter of the Refin, floats on the lurface. 
 
 C O C C U LU S INDUS is the berry of an oriental plant, fuppofed to be yjjj 
 a fpecies of Solarium , and called by Ray Solarium racemofum Indicum , &c. or I n_ (g 0ccul ° us 
 dian-tree Nightfhade producing its fruit in clufters like grapes. The berries j NDUS 
 are brought to us from Alexandria and other parts of the Levant. They are \ 
 
 partly about the fize of Bay-berries, and partly of that of Chich-peas ; roun- 
 difh, but hollowed in a little towards the {talk, and approaching to a kidney 
 fhape, rough on theoutfide, and of a grey-brownifb or blackifh colour: The 
 frelber they are, the heavier ; the older, the dryer and lighter. 
 
 In their ftrudture, they greatly refemble the Coccognidia, confiding of two 
 fhells and a kernel, in which laft their aftivity refides : The outer fliell is thin, 
 the inner thicker and whitifh; the kernel is more manifeftly of a kidney fhape 
 than the entire berry, when frefh of a white colour, but very apt to grow yel- 
 low and brown : It foon likewife becomes rancid, and is preyed on by worms, 
 infomuch that molt of the berries, as we commonly meet with them, are found 
 £0 be mere fhells without any kernel. 
 
 The Cocculus Indus agrees alio with Coccognidium in its deleterious pur- 
 gative and emetic quality, though it does not difcover fuch a burning heat in 
 the mouth, and imprefles only a kind of bitternefs. In Wepfer’s treatife on 
 the Cicuta aquatica , there are feveral observations of the effefts of this berry on 
 cats and dogs : Some died' in a fhort time, vehemently convulfed : Others, 
 after iuffering violent torments recovered — — Some recommend it to be held 
 in the mouth for abating toothachs, or a mixture of it with one third its weight 
 of Sal ammoniac to be put into the hollow tooth ; but even this ufe of it is 
 fcarcely fafe. It is principally employed in ointments for deftroying cutaneous 
 infefts, and in fifhing. For this laft purpofe, a mixture of the powdered Coc- 
 culus with Rye-meal, old Cheefe, Spirit of Wine and other fubftances, is 
 formed into fmall pellets or pills, which are ufed as a bait, or only thrown by 
 themfelves into waters ftocked with fifh The fillies by fwallowing the pills, 
 are llupefied and benumbed, arife to the furface, and may be ealily caught by 
 the hands. 
 
 The Cocculus indus contains a grofs Oil like the Coccognidium, but in lefs 
 quantity; the Oil does not feparate on treating the berry with water or fpirit, 
 but remains united with the extracts, and renders the fpirituous in particular 
 
 Y y _ quits 
 
Plants and their Part s. 
 
 CoccuLUsquite uridtuous. An ounce of Cocculns gave one dram of fpirituous, and 
 Indus, afterwards three drams of watery extract ; four drams remaining undiffolved. 
 L— — ' On inverting the order of applying the menftrua, the quantity of the refpedtive 
 products was exadtly the fame, water extracting at firft three drams, and fpirit, 
 afterwards, one. The watery extract tafted ftrongerthan the fpirituous. 
 
 IX. NUX VOMICA, fo called, is not a nut, but the feed of a fruit like an 
 Nux Orange, growing in the Eaft-Indies : It is called by the Germans Krahen-augen, 
 Vomica. Crows-eyes, from its having fomewhat of the appearance of a grey eye, and 
 from its being poifonous to crows. The tree is defcribed and figured in the 
 Hortus Malobaricus under the name of Caniram. The feeds brought to us are 
 of different fizes, and produced by different fpecies of the plant : The tree 
 which yields the finaller fort is that whofe roots are the Lignum colubrinum of the 
 fhops. They are commonly of a roundilh flat figure varioufly bent, with a 
 navel or prominence in the middle, covered all over with fine fhort hairs like 
 velvet : The kernel is nearly of the confidence of horn, but harder and more 
 brittle, foas to be beat in pieces by a hammer. 
 
 An ounce of Nux vomica, rafped into fine powder, yielded with water half an 
 ounce of gummy extradt, and afterwards with fpirit only five grains of Refin ; 
 another ounce, treated firft with fpirit, gave one dram thirty-two grains of 
 refinous extradt, and afterwards two drams thirty-fix grains of Mucilage; the 
 indiffoluble part amounting to about half the weight of the feed. Both the 
 watery and fpirituous extra&s, prepared at firft, are very bitter, particularly 
 the fpirituous : Thofe made by either menftruum, after the other has per- 
 formed its office, have little bitternefs. In diftillation, neither water nor fpirit 
 bring over any thing remarkable. The watery fpirit of Sal ammoniac digefted 
 on this feed, gains a deeper colour than any other menftruum ; the tindture is 
 brownifh-red. The vinous Spirit of Sal ammoniac fcarce extracts a yellowifh 
 hue ; and Ample Spirit of Wine receives no tinge at all. 
 
 Nux vomica is poifonous to dogs, to other carnivorous animals, and fuch as 
 are born blind. It does not indeed follow from hence that it is poifonous to 
 men; and fome have even recommended it as a notable diaphoretic and alexi- 
 pharmac ; and Melichius obferves that it is eaten by the Turks without injury. 
 But Seutter tells us of a woman in Holland, who on taking a dofe of Nux vo- 
 mica, mixed with a little Gentian, for the cure of an intermitting fever, was 
 thrown into violent convulfions, from which fhe difficultly efcaped with her 
 life : This one example is fufficient to deter us from the ufe of the Nux vomica, 
 efpecially as we arefurnifhed with efficacious and unfufpedted medicines for all 
 the intentions in which it is recommended. It is obfervable, that the outer 
 fkin, and its hairy covering, are more virulent than the kernel. 
 
 X. St. IGNATIUS’s BEAN, Faba fantli Ignatii, Fab a febrifuga Bironis, 
 Ignatius’s ls a f ur t & c ‘ * s not a t>ean, but the feed of a fruit of the gourd kind. The beft 
 Bean, account of the plant that has yet appeared, is that fent by Father Camelli to Ray 
 -v— — ^ and Petiver, and publifhed in the Philofophical Tranfadtions for the year 1699 : 
 He obferves, that it grows in the Philippine iflands, a'nd winds itfelf about the 
 talleft trees to the top ; that it has large, ribbed, bitter leaves, a flower like 
 
 that 
 
Plants and then - Part s* 347 
 
 that of the Pomegranate, and a fruit larger than a Melon. Some referable the Ignatius’s 
 fruit to a Pomegranate, probably from mifapplying Camelii’s words. The Beam. 
 fruit is covered with a thin, gloffy, blackifh- green, and as it were marbled 
 Ihell, under which is lodged another of a ftony hardnefs : Within this is con- 
 tained a loft, yellow, bitterifh pulp, in which lie the feeds or beans to the num- 
 ber commonly of twenty-four, each covered with a filvery down. 
 
 The fame gentleman gives an account of the virtues attributed to thefe feeds 
 by the Indians ; but experience has fhewn that they are dangerous. Konig re- 
 lates that a perfon, by drinking fome of a fpirituous tinflure of them inftead of 
 Aqua vitae, was thrown into ftrong convulfions ; and Dr. Grim, that a dram 
 of the feed in fubftance occalioned, for a time, a total deprivation of the fenfes.. 
 
 Others mention violent vomitings and purgings from its ufe. The only good 
 effedl I have myfelf obferved from this feed is the removal of intermitting fe- 
 vers by drinking, on the approach of a paroxyfm, an infufion of fome grains of 
 the Bean made in Carduus water : We are not however from hence to look upon 
 this medicine as an univerfal Febrifuge, or to ufe it indifcriminately. 
 
 Thefe Beans (for fo cuftom requires that wefnould call them) are about the 
 fize of a moderately large Nutmeg; in figure fomewhat roundifli, but ex- 
 tremely irregular, fcarcely any two being entirely alike, full of unequal depref- 
 lions and prominencies ; in colour, externally yellowifh-brown, but when the 
 outer fkin is taken off, of a blackifh- brown, and in part quite blackifh ; in 
 confidence hard and compadt as horn, fo as not to be reducible into a powdery 
 form but by cutting or rafping : For all their hardnefs, however, they are not 
 proof againft worms. When frefh, they have fomewhat of a mufky fmell, 
 which by age is loft : Their tafte is very bitter, refembled by fome to that of 
 Centaury. 
 
 Four drams of thefe Beans, boiled in water, gave juft two drams of gummy 
 <-= extract; after which, rectified Spirit of Wine fcarcely took up half a grain. 
 
 Half an ounce, treated firft with fpirit, gave two lcruples and a half of refinous 
 extract, and afterwards with water three fcruples and a half of a gummy one. 
 
 The fpirituous extract made at firft is of a yellowilh colour, and the watery 
 greenifh. They are both bitter : The fpirituous imprefles at firft a very agree- 
 able bitternefs, fomewhat like that of Peach-kernels *, which going oft', leaves 
 in the mouth a ftrong bitter. The diftilled liquors have no tafte or fmell. 
 
 THE name Hellebore, fuppofed to be derived from lAAffVfS opd to kill by 
 eating, is applied to different rofaceous-flowered plants. The white Helle- White 
 bore is made by Tournefort a diftincft genus from the black, under the name Hellebore, 
 of Veratrum ; its feed veffels wanting the horns which thofe of the other have, 
 and its feeds being furrounded with a leafy margin, which thofe of the other 
 are not : Fie calls the officinal fpecies Veratrum flore fubviridi , greenifh- 
 flowered Veratrum , in diftin&ion from another, whole flowers are of a blackfill 
 red colour. 
 
 This plant grows wild in France, Switzerland, Auftria and other countries,, 
 but is not a native of Germany. The root, which is the only part made ufe 
 ©f, is oblong, an inch thick or more, of a blackifh grey colour on the out- 
 
 Y y a. fide 
 
34-8 Plants and their Parts. 
 
 White fide and white within, furrounded with final 1 fibres, crooked and unequal, of 
 Hellebore. a nau f e0us> acrid, bitterifh, aftringent tafte, and no fmell. 
 
 v Two ounces of white Hellebore-root yielded with Water nine drams and a 
 fcruple of gummy extract; and afterwards, with Spirit, only half a fcruple of 
 Refin. The fame quantity, treated fir ft with Spirit, yielded feven drams of 
 refinous, and afterwards with Water near three drams of gummy extract. 
 Neither Water nor Spirit elevate any thing remarkable in diftillation. 
 
 White Hellebore-root is a violent emetic : Matthiolus reports, that the 
 Spaniards prepare an adtual poifon from it. The refinous preparations are 
 particularly unfafe. A tindfure made with Spirit of Wine from two ounces of 
 Bryony-roots, two ounces of Sowbread-roots, and one ounce of white Helle- 
 bore- roots, was formerly in fome efteem as an emetic, under the title of Vo- 
 mitorium conradinum : So great is the adlivity of this liquor, that the little which 
 a feather takes up, not exceeding perhaps two drops, received in Wine, is 
 a fufficient dole. This root has been fuppofed peculiarly ferviceable in mania- 
 cal diforders : Its violence however is fo great, that it is molt prudently re- 
 frained from : There are leveral inftances in the Ephemerides naturae curioforum 
 and other books, of its having proved fatal. 
 
 Its principal ufe is as a purge and vomit for cattle; in ointments againft 
 fome kinds of cutaneous eruptions, and infects; and as a fternutatory. A red 
 Sternutatory powder, may be made by moiftening, with a tindture of the Helle- 
 bore-root, powdered clovy July-fiowers, which may be ground with a little 
 Almonds to improve the colour; a green one with powdered Betony leaves, 
 and a white with Creme of Tartar or Sugar. 
 
 XII. THE roots of Black Hellebore confift of a number of (lender black or 
 Black brownifh- black fibres hanging from one head; the fibres, which are the part 
 Hellebore. ma d e ufe of, have nothing of the woody pith, which fome diredt us to fearch 
 for and throwaway. The narrower-leaved Black-hellebore with Rofe-coloured 
 flowers is the fpecies whofe roots are generally underftood as the officinal kind ; 
 thole of the larger-leaved fort are little different ; thole of the garden green- 
 flowered Black-hellebore are inferior in quality to both the others, though 
 among us (in Germany) mod commonly made ufe of. All the three grow wild 
 in feveral of the mountainous parts of Europe, as in Tyrol, Switzerland, Au- 
 ftria, England, &c. 
 
 The roots of Aconite orNapellus greatly refemble thofe of Black-hellebore, 
 and have fometimes been miftaken for them : Of the unhappy confequences 
 arifingfrom this miftake, there is an account in the Breflau colledtions for the 
 year 1720. As the Aconite-roots incline more to a brown than a blackifh co- 
 lour, wefhould be careful in purchafing Hellebore, to chufe the blacked : In 
 this light, the firft of the Hellebores above-mentioned is to be preferred, as its 
 roots are blacked, and confequently the moft diftinguifliable from the poifon- 
 ous root. 
 
 Black-hellebore root has a naufeous fweetifh tafte; which is followed by a 
 bitter one that dwells long upon the tongue : It has no fmell. No one has 
 given any fatisfadfory chemical analyfis of it, but Monf. Boulduc : The ex- 
 periments, however, which that gentleman gave in to the French Academy, 
 
 were 
 
Plants and their Parts. 
 
 3+9 
 
 were not made by himfelf, but by a German chemift, Dr. Groffe. In my 
 experiments, fix ounces of the root, treated firft with rectified lpirit, gave fix 
 drams and a fcruple of extradt •, after which, water extracted three drams one 
 grain and a half : Water applied at fir ft took up fix drams two grains, and 
 redined fpirit afterwards three drams one grain. Thus which foever men- 
 ftruum we apply at firft, it extrads about fix fixteenths, leaving three fix- 
 teenths which may be extraded by the other j about feven fixteenths remaining 
 unaffcded by either. 
 
 The lpirituous extrad, whether made from the root diredly, or from fuch 
 as has undergone the adion of water, appears of a foft unduous confiftence, 
 this root containing a portion of grots Oil, of the expreffible kind •, a principle 
 which efcaped Boulduc’s examination. The fpirituous extrad made at firft, 
 being digefted in water, about three fourths of it were diffolved, and the re- 
 maining fourth proved a quite thin oily-refinous matter. Some report that the 
 diftilled water has a manifeftly fharp tafte. Borrichius relates, in his apology 
 againft Conringius, that a water diftilled from Black- hellebore in the heat of 
 a water-bath, given to a boy to the quantity of eight fpoonfuls, occafioned 
 gripes and motions to ftool ; and that a dog, by twelve fpoonfuls, was four 
 times vomited, and twice purged. This experiment deferves to be farther 
 examined : The diftillation feems to have been made from the entire plant. 
 
 The root in fubftance is a ftrong ftimulating cathartic, and in fmaller dofes, 
 a powerful aperient : Hence it is recommended in maniacal, and melancholic 
 and hypochondriacal diforders, in quartan agues, in menftrual and other ob- 
 ftrudtions. The beft preparation is a watery extradt made by long boiling, 
 which may be given from three to fix grains made into pills with other ingre- 
 dients : The fpirituous extradt is too violent. 
 
 Black 
 
 Hellebore. 
 
 AGARIC is a fpongy fungous fubftance growing on the trunk of a tree, XIIL 
 or in the language of the ancients, an excrefcence or apoftem from age or Agaric 
 difeafe. The tree is the common Larch, from which Turpentine is obtained. i_ — 
 
 (See page 2S7.) It grows wild in Dauphiny, Savoy, on the Alps, in Auftria, 
 
 Tartary, &c. and is the only coniferous tree that fheds its leaves in the winter: 
 
 When it grows old, the fungus comes forth in feveral places on its trunk, and 
 if the tree is large, on the firft branches. 
 
 The fungus is of various fizes, fometimes not exceeding the bignefs of the 
 lift, fometimes as large as a man’s head : It takes at leaft a year to grow to its 
 full fize. There are two kinds of it, called by the ancients Mas and Femina. 
 
 The male Agaric is dark-coloured, hard, heavy and woody : It is feldom 
 
 taken from the Larch, but chiefly from old Oak-trees, and hence is called by 
 lome Agaric of the Oak : It is quite unfit for any medicinal ufe, and is only 
 now and then employed by the dyers as an ingredient in the black dye. The 
 female or officinal Agaric is covered with a hard blackiffi rind like the other ; 
 but when the cortical part is pared off, the internal fubftance appears quite 
 white: By age, it changes a little yellowifh. It fhould be very light, porous, 
 eafy to break, free from any hard pieces or compadt veins. Tafted, it proves 
 at firft fweetifh, but prefently becomes very bitter and naufeous. 
 
 As. 
 
Plants and their Parts. 
 
 As Agaric is an excrefcence from a very refinous tree, it is natural for it to 
 be rich in Refin. We find in effect that it contains three fourths its weight of 
 refinous matter, and that che remaining fourth is a ilimy, mucilaginous, earthy 
 liibflance, fo tenacious as fear ce to be by any means diffolved or divided j 
 continuing, however treated with water, a tough gluey pafte. The purgative 
 quality of Agaric refides in the Refin : To the glutinous matter we may attri- 
 bute the dangerous confequences, which, when given in fubflance, however 
 corre&ed, it is apt to produce. No wonder that fuch a cohefive indiffoluble 
 fubftance fhould adhere, pertinacioufly to the ftomach and inteftines, and oc- 
 cafion gripes and other inconveniencies. 
 
 From eight ounces of very good Agaric, I obtained by re&ified fpirit, fix 
 ounces of refinous extradl : From the refiduum, only two drams and two 
 
 fcruples of watery extra£f : The indiffoluble tenacious matter weighed two 
 ounces one dram and a half 5 fo that there was upon the whole an mcreafe of 
 near half an ounce above the original weight of the Agaric, from a part of the 
 menftrua retained. On applying water at firfl, I got but bare three drams of 
 extract ; on treating the remainder with fpirit, I gained near as much Refm as 
 when fpirit was ufed ffrft, namely five ounces and feven drams the indiffo- 
 luble matter weighed, when dry, two ounces two drams. 
 
 In reducing Agaric to powder, whether by the rafp or the peftle, great care 
 muft be taken to avoid the fine duff that flies off; which is not only apt to oc- 
 cafion violent fneezing, and inflammations of the eyes, but is Jikewife very 
 prejudicial to the breaft. Agaric cannot of itfelf be pulverized in a mortar, 
 on account of its glutinous fubftance : The beft way of obtaining a powder 
 
 from it is, firft to rafp, and then make it into a pafte with Mucilage of Gum 
 Tragacanth : When this is thoroughly dry, great part of it may be beat into a 
 fine powder, and by treating the remainder in the fame manner, the whole will 
 at length be got through the fieve. It might be fuppofed, that as it is the mu- 
 cilaginous part of Agaric itfelf that prevents its pulverization, the addition of 
 frefti Mucilage would do more harm than good j but the Mucilage of Gum 
 Tragacanth is of a quite different nature from that of Agaric, being foluble, 
 liarmlefs, when dry brittle, and rendering the Agaric alfo brittle and pulverable 
 along with it. The troches of Agaric, a preparation formerly in efteem, and 
 ftill retained in many difpenfatories, are likewife moft commodioufly made up 
 with this addition : When formed with only an intufion of Ginger and Wine, 
 as directed by the ancients, they do not dry *, nor does Zwelfer’s method, of 
 making them up in frofty weather, fucceed : A ftrong froft will indeed freeze 
 them, buc when the froft is gone, they thaw into a pap again. In fome dif- 
 penfatories, a refinous extract is directed to be prepared from this fungus by 
 rectified fpirit. An extraction may be. made from it, of which a Angle drop 
 is capable of exciting vomiting (d). 
 
 COLO- 
 
 (d) One drop let fall on the tongue , occafons 
 vomiting, and a difgujl to food for a whole day,,] 
 This is reported by Boulduc, of a fpirituous 
 tinClure made from the cortical part of A- 
 garic; and from him our author feems to 
 have borrowed the obfervation. I have not 
 iound that the ftrongeft tinctures of the 
 
 common Agaric of the fhops produce any 
 fuch effeeft : To the tafte they are remark- 
 ably fweet, and their fweetnefs is very dur- 
 able in the mouth, but becomes unpleafant, 
 though in no very great degree, before it 
 goes off. 
 
Plants and their Parts* 
 
 351 
 
 COLOCYNTH or Coloquintida is the fruit of a plant of the Gourd XIV, 
 kind, growing plentifully in Perfia, differing from other Gourds in the leaves, Colocyntk, 
 being deeply cut in, but more remarkably in the quality of the fruit, which is 
 fo intenfely bitter as to have received the names of Gall of the Earth, Bitter 
 Apple, Devil’s Apple, GV. The medullary fungous part of the fruit, freed 
 from the rind, is brought to us from Egypt and Aleppo. 
 
 Mr. Boulduc has given fome experiments on Colocynth, with which mine 
 do not entirely agree. He allures us, that on fomenting it with Muft, and 
 then diftilling the liquor, he obtained a bitter purgative fpirit : I repeated the 
 procefs, ufing only Wine and Sugar inftead of Muft, which could not make 
 any material difference ; but without finding that the diftilled fpirit had the 
 leaft bitternefs or purgative quality. Boulduc obtained from a pound of die 
 pulp, only an ounce of fpirituous extract, and from another pound only two 
 ounces and a half of watery extract ; whereas in my experiments, the fpiritu- 
 ous extract amounted to three ounces and a half, and the watery to feven and. 
 a half. When fpirit was applied at firft, I gained from the remainder four 
 ounces and a half of watery extract ; and when water was firft applied, the re- 
 fzduum yielded three drams forty-four grains to fpirit. 
 
 The feeds differ remarkably from the pulp; whilft the latter gives out half 
 its weight of gummy and refmous matter, the former yield but one eighth, nor 
 is there much difference in the quantity of extracts, whether water or fpirit are 
 ufed firft, the fpirituous amounting only to eight fcruples on the pound more 
 than the watery. The fpirituous extract of the feeds is manifeftly un&uous or 
 oily, though I could not feparate any Oil by expreflion on committing feveral 
 pounds to the operation at once. All the extradls made from the pulp are 
 much bitterer than thofe from the feeds, the firft extracts bitterer than the fe- 
 cond, and the diftilled liquors, both watery and fpirituous, infipid and ino- 
 dorous. 
 
 The pulp of Colocynth is a violent purgative, apt to bring on convulfions 
 and inflammations of the bowels. Many attempts have been made to corredt 
 it, by alcalies both fixed and volatile, vegetable acids, neutral falts, aroma- 
 tics, &c. but the moft prudent way is to refrain from it altogether, or to ufe 
 only a watery extradft made by long boiling : By long boiling with water, all 
 the draftic vegetables lofe their virulence and become mild. (See p. 268). 
 
 THERE are two forts of Bryony one bearing red, the other black berries: 
 The firft is the moft common about Berlin, climbing upon hedges, trees, old 
 walls, Gfr. The roots of both forts are alike both in quality and appearance : 
 They are moderately large, often forked, fo as to be refembied to the human 
 body, and are by fome cut into various figures and put off for mandrakes : 
 They are externally of a yellowifh colour, internally white and porous, of a 
 bitterifh, acrid, aftringent tafte, and a difagreeable fmell, which is in great 
 meafure loft by drying. 
 
 Bryony-root is a ftrong purgative, and as fuch has been recommended in 
 hydropic cafes : It appears however not to be entirely fafe. Mechoacan, an 
 American root whofe ufe had long been luperfeded by Rhubarb, was again 
 
 had 
 
 XV. 
 
 Bryonv . 1 
 
352 Plants and their Parts. 
 
 Bryony, had recourfe to in Germany fome years ago, on the failure of Rhubarb from 
 u— v — ^ wars in Perfia: Mechoacan thus grew fcarce, but prefently the fhops were 
 Hocked, in lefs time than they could be fuppofed to have received fupplies from 
 America ; and the roots looked alfo quite frefh, and different from what 
 Mechoacan ufed to be. Thefe roots were probably Bryony, which in appear- 
 ance does not ill refemble Mechoacan. They were often productive of dan- 
 gerous, and even fatal fymptoms: In a few minutes after taking them, con- 
 vulfions, a deprivation of the fenfes, fwelling of the eyes and head, frequently 
 fucceeded, not only in children, but in adults of the ftrongeft conftitution. 
 Platerus probably had experienced fome ill effects from Bryony- root, or he 
 would not have taken the trouble of drying and infufing it fo often in Wine, 
 to fit it for medicinal ufe. 
 
 Boulduc, relates, in the French Memoirs, that this root contains only fa- 
 line principles, and no Refin. In my experiments a true Refin was gained 
 from it, but no Salt could be feparated, though it doubtlefs does contain a 
 portion of faline matter, as the juice, added to a folution of Sulphur made 
 with Quick-lime, occafions a precipitation, accompanied with a fetid froell. 
 It precipitates alfo folution of fublimate, and in fome degree that of blue Vitriol-, 
 but thefe precipitations are no mark of a Salt, and proceed from the feculent 
 part of the juice. 
 
 A pound of the frefh roots yield near fix ounces of juice, which retains 
 much of the ill fmell and tafle of the root : On ftanding, it depofites a white 
 powdery matter, called fecula of Bryony, and recommended as a milder pur- 
 gative than the root in fubftance. Two ounces of the dry root yielded with 
 Water ten drams fix grains of gummy extract, and afterwards with Spirit 
 twenty-three grains of Refin five drams thirty-two grains remaining undif- 
 folved. It is pretty remarkable, that the refiduum was in larger quantity 
 when Spirit was applied firft : By this method of application, I obtained, 
 from two ounces, of refinous extract two drams two fcruples and a half, and 
 afterwards four drams one fcruple of a gummy one ; eight drams two fcruples 
 and fix grains remaining. 
 
 XVI. Jalap is the root of a fpecies of convolvulus, with leaves like thofe of 
 Jalap. ^ ut n01: f° thick, and beautiful red flowers, which have this remarkable 
 \ i property, that they open in the night, and fhut again on -the leaf!; appearance 
 
 of the fun ; whence the plant is called by the French Belle de nuit , the beauty 
 or fair one of the night : In rainy or cloudy days, the flowers open a little, 
 but fall off the fooner, as if day-light was injurious to them. The Jalap-plant 
 is a native of the province Chalapa or Xalapa in New Spain, from whence its 
 name is derived, and written, according to the pronunciation of different lan- 
 guages, Jadapa or Jalapium , Gialappa , Chalapa , Xalapa, Zalapa , &c. 1'he 
 roots raifed in Europe have been found much weaker than the American. 
 
 Jalap is brought over in thin flices-, of which the befi: are compact and 
 hard, fo as not to be broke by the fingers, ponderous, of a dark brown colour, 
 of a gloffy refinous appearance, or at lead furnifhed with refinous ftreaks and 
 circles, eafily inflammable, of no fmell, or a faint unpleafant one, and of a 
 flight acrid tafte : The fine duff, which flies off in powdering them, provokes 
 
 5 fneezing. 
 
Plants and their Parts* 353 
 
 fneezing. Thofe which are thoroughly refinous, are not liable to be worm J a l a p, 
 eaten, the worms preying chiefly upon the gummy or mucilaginous parts, and 
 not touching the refin, or at leaft not till thefe are confumed : Hence we may 
 fuppofe the worm eaten roots to have been originally of a bad kind, produced 
 in moift foils or rainy feafons, &c. and hence the worm eaten may be employed 
 for making extrads equally with any other, the Refin being equal in goodnefs, 
 though lefs in quantity. 
 
 From fixteen ounces of good jalap-root I obtained, by Spirit of Wine, five 
 ounces and four fcruples of refinous extrad, and afterwards by Water two 
 ounces and a half of a gummy one : On applying Water at firft, 1 gained 
 four ounces and a half of gummy extrad, together with fix drams of a reft- 
 nous matter which fell to the bottom in evaporating the decodion ; the re- 
 mainder yielded, with Spirit, three ounces of Refin : The indilfoluble part 
 amounted in the firft cafe to eight ounces three drams, in the latter to fevers 
 ounces fix drams. By precipitating a fpirituous tindure of the root with Water, 
 
 I gained, from a pound, four ounces of pure Refin. 
 
 The inferior forts of Jalap yield lefs refinous and more gummy extrad: Such 
 muft have been that employed by Boulduc, who obtained, from fixteen ounces, 
 only two ounces five drams and a fcruple of refinous extrad, but upwards of 
 eight ounces and a half of a gummy one. 
 
 Jalap is a moderately ftrong, but a fafe purgative, and wants none of the cor- 
 redors which officious induftry has contrived for it. It is given in dofes of a 
 fcruple, with the addition of an equal quantity of vitriolated Tartar, and a 
 few drops of Oil of Anifeeds. The pure Refin indeed is not to be ventured 
 on without a corredor, as it gripes violently •, but the proper corredion does 
 not confift in lefifening its power, but in dividing and rendering it foluble in the 
 animal fluids : For this purpofe nothing anfwers better than grinding it with 
 almonds, pine-nuts, yolk of eggs or other like fubftances, into the form of an 
 emulfion. With regard to the different preparations of this root a folution of 
 the Refin in Spirit of Wine, diluted with watery liquors by the mediation of 
 Sugar or other fubftances that may prevent its feparation, purges much more 
 powerfully than the Refin given in a folid form however divided. A water y 
 extrad made from Jalap, after the adion of fpirit, promotes urine, but fcarce 
 proves at all purgative : This preparation was ufed by Borellus as an arcanum 
 in dropftes. The watery extrad made at firft is both diuretic and weakly pur- 
 gative. A compound extrad made by Water and Spirit together, contains 
 all the foluble parts of the root, and operates powerfully both by urine and 
 ftool. 
 
 It is obfervable of this root, that it has a notable degree of fermentative 
 power; exciting this adion in grofs fweet vegetable juices, as melafles, and at 
 the fame time impregnating them with its purgative quality. 
 
 SOME years ago another purging root was brought from America under the XVII. 
 name of Mattalista, of which, in Holland, there are twoforts, a coarfer andMATTAusr, 
 a finer: One is faid to be the produce chiefly of the French Weft Indies ; the 
 other of New Spain, and Aquacathan in New Gallicia. It is called in Aine- 
 
 Z z rica 
 
354 
 
 Plan t s and their Parts. 
 
 Mattalist. rica Battata da purga. The plant is as yet unknown. The only botaniH; I' 
 know of, that makes any mention of it, is John Bauhine, who calls it Radix 
 purgativa indica. This root is chiefly recommended as a purgative in bilious 
 complaints : It is nearly of a middle ftrength betwixt Jalap and Mechoacan, 
 being weaker than the firft and Wronger than the laft. it yields a Re fin fimilar 
 to that of Jalap, but in lefs quantity ; only ten drams, or an ounce and a half 
 at moil, being obtainable from fixteen ounces of Matcalifta. 
 
 XVIII. TURBITH is the root of a large convolvulus, growing in nro iff places 
 Turbith. near the fea coafls, in the ifiand Ceylon, Suratte, Malabar, Goa, but molt; 
 
 plentifully in Guzarotta, from whence the greateft quantities of the roots are 
 brought into Europe. The root is commonly about the thicknefs of the lin- 
 ger, though fometimes twice or thrice as thick, brownifh on the ou tilde, 
 whitilh within, with a white fpongy woody pith : Its tafte is at firft fweetifh, 
 afterwards acrid and difagreeable. 
 
 The Indians formerly flit the roots longitudinally, and took out the woody 
 matter. At prefent the roots are generally brought over pith and all, being 
 only cut tranfverfely into oblong pieces, which are often found to be fcorched 
 at the ends : The ufe of the fcorching is to fear up the divided veflels, and 
 prevent the oozing out of the refinous yellowifh juice, with which the frefli 
 roots abound. Albinus’s fuipicion, that this juice is defignediy extraded from 
 them, before they come to us, appears to be groundlefs. 
 
 Sixteen ounces of Turbith root yielded with Water feven ounces three dram3 
 of gummy extrad, and afterwards with Spirit only five drams forty-five grains 
 of Refin : Another pound, treated firft with redified Spirit, gave two ounces 
 of refinous •, and afterwards with Water, fix ounces eight fcruples of gummy 
 extrad. The indiffoluble earthy part amounts in both cafes to fomewhat 
 more than half the weight of the Turbith : Its quantity is fomewhat greater 
 when Spirit, than when Water is applied firft Water diftilled from Tur- 
 
 bith difcovers a naufeous fmell and tafte, but no Oil. 
 
 Turbith root is a moderately ftrong purgative : As fuch the root in fub- 
 fiance was formerly given, from a fcruple to half a dram, and the Refin to 
 half a fcruple 3 but fince the introdudion of Jalap, Turbith has been 
 rarely ufed. 
 
 XIX. HERMOD ACT YL is a root of the ftiape of a heart flatted ; not at all 
 Hermodac. of the fhape of a finger, which its name feems to imply. It comes chiefly from 
 Aleppo and Smyrna, by the way of Venice. The plant is wholly unknown: 
 For the fpecies of Iris given by Tournefort and Boerhaave, and the Colchicum 
 by others, for the true Hermodadyl plant, have roots, according to their own 
 account, entirely different from the officinal Hermodadyl. 
 
 We meet with Hermodadyls of various colours and flzes, white, reddifh, 
 yellowifh, brownifh, fmall and large, wrinkled and fmooth : The beft are 
 white both externally and internally, folid and compad, yet eafily reduci- 
 ble into a powder, which looks like Wheat-flour, and does not greatly differ 
 in tafte. This root is generally held a purgative, by fome a ftrong one : It 
 does not appear, however, to have any adivity at all, Hermann juftly ob- 
 serves 
 
Plants and their Parts® 355 
 
 ferves that when dry, it is entirely if not altogether inert: But on what foun- H ermodac. 
 dation he afferts that ‘it is purgative when frefh, I know not, for he certainly ^ 
 never faw the frefh roots. 
 
 The chemical compofition of this root is pretty extraordinary. Two ounces 
 of Hermodadyls, cut fmall, yielded with redified Spirit a dram and a half 
 of refinous extrad, and afterwards with Water an ounce of gummy extrad , 
 fix drams and a half remaining undiffolved. If we invert the order, and ap- 
 ply Water at firft, inftead of an ounce of gummy extrad, we obtain but half 
 an ounce and three grains, and yet the refiduutn gives out nothing to redifie-d 
 Spirit, how long foever the digeftion is continued : This refiduum weighs 
 one ounce and a half, and does not look near fo dark coloured as that from 
 which more has been extraded, but femitranfparent, almoft like horn. Thefe 
 remarkable differences in the effeds of Water and Spirit, according as either 
 is applied firft to the root, may deferve further enquiry. 
 
 CLASS III. 
 
 Gummy-Refinons Vegetables . 
 
 G UMMY-Refinous fubftances are thofe, whole medicinal activity or 
 
 colour refide in fuch a combination of refinous and gummy matter, as R ESi ^ 0! * 
 to be extraded by Water, fometimes more perfedly than by Spirit, and not , Ji> ] 
 only by boiling but by infufion in Water. Moft of the bodies of this ciafs, after 
 repeated infufion in Water, yield ftill a portion of refinous matter to redified 
 Spirit : But the Refin thus obtained has generally little or nothing of the dif- 
 tinguifhing tafte or virtue of the fubjed. To this divifion belong fome of the 
 emetics, as Tobacco, Afarum, Ipecacoanha, Arnica ; a few of the purgatives, 
 as Sena, Rhubarb, Rhapontic ; moft of the aftringents, as Tormentil and 
 Galls ; moft of the bitters, as Gentian, Centaury, Carduus j fome of the 
 colouring drugs, as Turmeric ; with many others of weaker or more com- 
 pounded qualities. 
 
 TOBACCO ( Petum , Nicotiana , Herba medicea , &c. ) was firft difcovered in j 
 the ifland Tobago ; brought into Europe, in the year 1559 or I 5 ^°> by Tobacco. 
 M. Nicot the French ambaffador in Portugal*, and prefented to Queen Cathe- « _ . - a 
 
 line de Medicis. It is now become the objed of very extenfive manufadures, 
 and cultivated in large quantity by the European colonies in America, as alio 
 in fome parts of Europe. There are different fpecies of the plant, and great 
 differences alfo in the qualities of one fpecies according to the ioil and climate : 
 ftill further differences are occafioned in the prepared Tobaccos and Snuffs, 
 from the manner of preparation, and the additions made ule of for communi- 
 cating colour, flavour, &A. 
 
 The leaves of this plant, taken internally, prove virulently emetic, cathar- 
 tic, and narcotic : Even in the common forms in which they are employed in 
 fuch immenfe quantities, they generally at firft diforder the conftitution, till 
 
 Z z 2 habitual 
 
35 6 Plan t $ and their Parts. 
 
 Tobacco, habitual ule, which fubdues many noxious things, has rendered them perhaps 
 v — innocent, and perhaps even necefifary. Diftilled in a retort without addition, 
 they yield an acrid empyreumatic Oil, which has been found, from repeated 
 trials, to be poifonous to fundry animals : It is probably on this Oil that the 
 effects of the fmoke of Tobacco depend, for when the plant is fet on fire, its 
 native qualities are deftroyed. 
 
 Tobacco lofes its virulence by long codtion in Water: Though all the 
 adtive parts of the herb are extradled by the Water, yet the extradt left upon 
 evaporating the liquor, taken in dofes of four or five grains, proves mildly 
 aperient and anodyne, and is faid to be of great fervice in diforders of the 
 bread : The longer the codtion is continued, a luitable quantity of Water be- 
 ing added for that purpofe, the milder is the extradt. 
 
 I analyfed three forts of Tobacco, the American canifter Tobacco, the 
 Dutch leaf, and the dried leaves of pur own growth. An ounce of the canif- 
 ter, treated firft with Water, gave four drams thirty grains of extradl; the 
 fame quantity of the Dutch, four drams ; of our own four drams fifty grains: 
 From the refiduum of the firft, rectified Spirit extradled thirty grains; from 
 
 that of the fecond, fixty; and from that of the third, thirty An ounce of 
 
 the canifter fort, treated firft with redlified Spirit, yielded one dram thirty 
 grains ; the fame quantity of the Dutch, two drams twenty grains ; and an 
 ounce of ours, two drams thirty grains : From the refiduum of the firft, Wa- 
 ter extradled three drams thirty grains ; from that of the fecond, two drams 
 forty grains ; of the third, two drams thirty grains. The indifloluble earthy 
 matter amounted, in each of the experiments, to three drams. 
 
 The fpiritous extradls, made from all the forts, were ftronger than the wa- 
 tery : That of the canifter fort was notably pungent on the tongue ; of the 
 Dutch, only bitterifh, without any acrimony : the fpirituous extradl of ours 
 tailed fomewhat pungent, but the watery only bitter. The fpirituous extradls 
 of all the forts are of a fine green colour, the watery of a yellowifh brown. 
 The diftilled Waters and Spirits have no tafte or fmell: Bohn, however, pre- 
 tends that the diftilled Water, efpecially if drawn from the juice of the herb.,, 
 will occafion vomiting if taken to the quantity of an. ounce or two, 
 
 jj„ ARNICA, Arnica plauenfis , is a fpecies of Doronicum ( Doronicum planta - 
 A & n j ch.& nis f 0 ^ 0 dterum C. B.) with leaves like thofe of Plantane, and yellow radi- 
 c. — v — ated flowers. The Bowers and leaves are emetic or purgative An infufion 
 of them is faid to be remarkably ferviceable for refolving coagulated blood 
 from falls, &c. and in obftrudlions of different kinds : See the Afla Beroli- 
 nenfia , the Brefiau Colledtions, and the Differtations of Albertus and Buchner 
 on this plant. 
 
 Two ounces of the flowers yielded w-ith redlified Spirit three drams of ex- 
 tradl; the fame quantity of the leaves only two and a half: With Water, the 
 leaves afforded moll, two ounces giving five drams and a half,, whilft the fame 
 quantity of the flowers gave but five drams. The watery extradt appears to 
 be the mildeft, and oftentimes does not occafion either vomiting or naufea. 
 Neither the leaves nor flowers have any remarkable fmell, or give over any 
 thing in diftillation* 
 
 5 
 
 IP EC A- 
 
357 
 
 Plants and their Parts. 
 
 IPECACOANHA, called by fome, from its medical virtue, and the HI. 
 place of its growth, the American or Peruvian antidyfenteric, and Brazilian Ipecaco. 
 root, is the root of a plant ranked by Ray as a fpecies of Herb-paris, and u--«y«****j 
 diftinguifhed by the name of Brazilian Herb-paris bearing a number of 
 berries. 
 
 There are four forts of Ipecacoanha ; grey, brown, white, and yellow. 
 
 The two firft are thofe which are molt common in the fhops : The third is 
 rarely brought into Europe ; and the fourth is mentioned only by Sherard, as 
 received in a prefent from Tournefort. With regard to the two laid I fhall ob- 
 ferve only, that the yellow is merely purgative, and does not, like tire others, 
 occafion any vomiting : And that the white vomits more mildly than the grey 
 or the brown. 
 
 Of the grey and brown, fome prefer the one, and others the other ; in Eng- 
 land, they are ufed promifcuoufly. It is in general fuppofed, that the grey 
 operates with greateft mildnefs : This however depends, not upon the root 
 being the grey or the brown fort, but on its being good of the kind •, I have 
 feen very good and very bad Ipecacoanha of both forts. 
 
 Both the brown and the grey agree in their external figure, being about the 
 thicknefs of a quill, very unequal and knotty : They have a bitterifh fome- 
 what acrid tafie, but difcover little or no fmell when the quantity examined 
 is fmall : In large quantity, they yield a difagreeable fmell, and in pulveriza- 
 tion, a kind of mufty one. The larger, compadt roots, of a refinous appear- 
 ance, are the beft : The {lender, blackifti brown, and thofe which are full of 
 fibres, the word. There grows in America another plant, called there Caa- 
 pa , whofe roots greatly refemble Ipecacoanha, and are frequently brought 
 over in its Head : This root is externally of a yeliowifh colour : It is 
 greatly inferior in virtue to the true Ipecacoanha, and therefore to be guarded 
 again Id. 
 
 Boulduc relates, that the brown Ipecacoanha does not contain fo much fo- 
 luble matter as the grey : Probably the brown he employed was of a bad kind, 
 for I have not obferved any fuch difference : Differences indeed there are, and 
 great ones, but they depend wholly, as already mentioned, on the root being 
 good or bad of the fort. Sixteen ounces of good Ipecacoanha yielded with fpi- 
 rit three ounces of refinous, and afterwards with water four ounces wanting 
 twofcruples of watery extract, eight ounces and fix drams remaining undif- 
 folved. Another pound of the fame, treated firft with water, gave five ounces 
 of gummy, and afterwards with fpirit ten drams of refinous extradt; the in- 
 diflfoluble part amounting to two fcruples more than in the former experi - 
 ment — --On the other hand, a pound of very bad Ipecacoanha yielded only an 
 ounce and a half of refinous, and the fame quantity of gummy extradl ; and 
 on inverting the order of applying the refpe&ive menftrua, two ounces fix 
 drams of gummy, and only a dram and a half of refinous extrail. 
 
 Ipecacoanha is one of the mildeft and fafeft emetics. Its firft introduction 
 Into Europe was in the time of Louis XIV. of France, by one Grenier a 
 French merchant, who brought an hundred and fifty pounds from Spain, of 
 which trials were made in the Hotel-dieu. Helvetius firft difcovered, to his 
 
 Mo ft. 
 
3$8 P l a n t s ami their Part s.. 
 
 Ipecacao. Moft Chriftian Majefty, its antidyfenteric virtues, for which he received a re- 
 u — — %— J ward of a thoufand louis-d’ors, as he informs us himfelf in his Treatife of 
 Difeafes and Specific Remedies. Experience has fince fhewn that it is often of 
 great fervice in dyfenteries, but not always. The French phyficians give it in 
 finall dofes, frequently repeared-, if it produces no amendment by the time 
 that three drams have been taken, they defift from any further ufe of it. They 
 employ it fometimes in the form of glyfter, but find that when thus managed, 
 it does not anfwer fo well as when fwallowed. 
 
 Some have fuppofed that the emetic virtue of Ipecacoanha refides in its 
 gummy parts, the cathartic in its refinous, and the aflringent in its earthy. 
 Thus much is certain, that neither the gummy nor the refinous parts, fepa- 
 rately or conjointly, are equally ferviceable in dyfenteries with the root in fub- 
 ftances, and that infufions of it in Wine are effectually emetic. 
 
 jy THE roots of Asarum feem to be nearly allied to Ipecacoanha. Though 
 
 As arum violentl y purgative and emetic when frefli, yet by keeping for three or four 
 years, and even by bare drying, they become far milder, fcarcely vomiting or 
 purging at all, but proving powerfully refolvent. An extradt made from 
 them by long boiling with water, lofes entirely the purgative virtue of the 
 root, and becomes refolvent, diaphoretic, and diuretic, Afarum roots agree 
 like wife with Ipecacoanha in their chemical analyfis. 
 
 V. SEN A is a fmall fhrub, with {harp- pointed leaves fomewhat like thofe of 
 
 Sena. Liquorice, rofaceous flowers, and flathooked pods or feedveflels : It grows 
 chiefly in Syria, Perfia, Arabia and Egypt : The leaves and pods are brought 
 to us immediately from Alexandria, whence the name Sena Alexandria. A 
 fpecies of Sena is found alfo in Italy, but much inferior in virtue to the orien- 
 tal : The leaves of this are readily diftinguifhed from thofe of the othe r, by their 
 being not pointed but broad at the end almoft in fhape of a heart. Pomet 
 mentions three forts of the foreign Sena ; the firft or beft is called Sene d ’ 
 Alexandrie , or Sene de laPalte , that is Tribute-fena, the Turks paying their tri- 
 bute in this beft fort the two others are Sene de Seyde or de Tripoli , and de 
 Moca. They are all the produce of one fpecies of plant, differing only accord- 
 ing to the foil and climate. The befl; Sena-leaves are of a fine green colour, 
 free from fpecks, fmooth and foftifh to the touch, and thoroughly dry, of a 
 confiderable degree of fmell, and a bitterifh fomewhat naufeous taflre. They 
 are often expreffed in prefcriptions [in Germany, (Ac. J by the letters S. S. S. 
 i. e. Sena Sine Stipitibus , Sena picked from the ftalks. 
 
 Sena is one of the milder purgatives. Its common dofe is two drams, in- 
 Fufed in water : It is rarely given in fublfance, on account of its bulkinefs. 
 The inconveniencies complained of in this medicine are, that it is apt to 
 occafion a naufea, flcknefs, and flatulencies which fome erroneoufly afcribe 
 to the ftalks and pods. The beft correctors are the ftarry-headed Anifeeds, 
 Cinnamon, Cloves, and Creme of Tartar. Mr. Marehand relates, in the 
 French Memoirs for the year 1701, that the dry leaves of the greater Water- 
 figwort ( Scrophularia aquatica major , C. B.) wholly take off its ill fmell and tafte, 
 equally with the Iquetaya celebrated for that purpofe by the Brazilians. 
 
 An 
 
Plants and their Parts. 339 
 
 An ounce of choice Sena, treated with frefh parcels of rectified Spirit of S e n a. 
 Wine, yielded two drams twenty-three grains of refmous extract : and after- c— v— — * 
 wards with water, two drams two fcruples of gummy extract, three drams and 
 three grains remaining undiffolved. Another ounce, treated firft: with water, 
 gave four drams and half a fcruple of gummy, and afterwards with fpirit only 
 twenty-eight grains of a refmous extract, which appeared to contain fome grofs 
 oily matter, and hence was difficultly reduced to drynefs ; the refiduum 
 weighed three drams and a fcruple. Valentini muft have operated very incu- 
 rioufly in obtaining but two ounces of extradt from a pound : I gained near 
 ten, reckoning the watery and fpirituous together ; and above eight of watery 
 extradl alone. 
 
 In diftillation rectified fpirit brings over nothing; the diftilled water is im- 
 pregnated with the fmell of the Sena, but difcovers no appearance of efiential 
 Oil. The activity of the Sena is greatly weakened by evaporation, efpecially 
 if the procefs is performed by a boiling heat in an open veffel, the extradt 
 proving far lefs purgative than an equivalent quantity of the infufion which it 
 was made from. The refmous extradt is more ungrateful in tafte than the 
 watery, and contains the green colour of the leaf. 
 
 R H U B A R Rheum, Rhabarbarum , (fuppofed to have been fo called from yj 
 its growing on the banks of the river Rha , now Wolga, in the barbarous country Rhubarb; 
 Ruffia) is at prefent brought only from China : Part comes by land through u — v — j 
 Ruffiia, and part by fea from the Eaft-Indies. It is the root of a plant which 
 agrees with the Docks in all its botanic characters but the flowers ; thofe of the 
 Docks confiding merely of threads or ftamina, whilft thofe of the Rhubarb plant 
 are furnifhed each with a Angle petalum fhaped like a bell and divided into fe- 
 veral fegments about the edges. The root is large, fometimes oblong and 
 fometimes roundifh, of a dark-brownifh colour on the outfide with black and 
 reddifh ftreaks, internally reddifh-yellow and full of a juice of the fame colour. 
 
 It is cured by cutting off the fmall fibres and the dark-coloured conical part, 
 not all at once but at intervals, the fide which is firft pared being laid upper- 
 mod: till the juice dries and concretes ; afterwards boring a hole through the 
 root, and hanging it up in a fhady place till thoroughly dry. 
 
 This root is exceeding fubjedt to lpoil, and to be preyed upon by worms, 
 unlefs kept perfedtly dry. The dealers frequently fill up the wormholes with a 
 mafscompofed of powdered Rhubarb and Mucilage of Gum Tragacanth ; and 
 colour the old decayed roots with an infufion of Rhubarb, Turmeric, or other 
 colouring drugs. When Rhubarb looks very frefli and fair externally, or of a 
 high yellow colour, we may fufpedt that it has fuffered thefe abufes. Good 
 Rhubarb is not of an uniform yellow, but variegated with brownifh and blackifli 
 (peeks, veins and circles : Internally it is reddifh, ftreaked and marbled as it 
 were like a Nutmeg : It is of afpongy texture, yet moderately heavy, firm, 
 
 and not eafy to break: It readily Rains the moift hand, and tinges the fpittle 
 on being chewed, of a deep yellow : Its fmell is unpleafant, its tafte difagree- 
 ably bitterifh. The roots of middling fize are better than the very fmall or the 
 very large ones : Some prefer the Ruffia or Turkey, and fome the Eaft-India 
 
 Rhubarb^, 
 
360 Plants and thtir Parts. 
 
 Rhubarb. Rhubarb, but both forts, if equally well cured and preferved, are of equal 
 — v— goodnefs (e). 
 
 An ounce of fine Rhubarb, reduced into grofs powder, yielded with highly 
 redtified Spirit of Wine three drams of extradt, and afterwards with water three 
 drams wanting half a fcruple-, therefiduum weighed two drams twelve grains. 
 On applying water at firft to another ounce of the fame, I obtained about as 
 much extradt as had been gained in the former cafe by the water and fpirit 
 both, namely fix drams all but half a fcruple; the refiduum gave out five 
 grains to rectified lpirit, two drams eight grains remaining undiffolved. 
 
 Thus we find that water extradts nearly all the foluble part of Rhubarb, but 
 lpirit little more than one half of it \ a proof that this rootcontains a much larger 
 proportion of gummy or mucilaginous than of refinous matter: Hence fpiritu- 
 ous tindtures of it are not precipitated or rendered milky by the addition of 
 water, like the tindtures of molt other vegetables. I examined alfo the folubility 
 of the aqueous and fpirituous extradts, each in its oppofite menflruum ; out of 
 fixty grains of the fpirituous extradt, water diffolved fifty-five, but out of the 
 fame quantity of the watery, redtified fpirit diffolved only eighteen. 
 
 The yellow colour of Rhubarb is remarkably lefs deftrudtible than many 
 ■other vegetable yellows : Aqua fortis and other acids, which deflroy the co- 
 lour of infufions of Saffron, Turmeric, &c. make no change in that of Rhu- 
 barb, or at mofl render it only turbid : Volatile fpirits heighten the colour, 
 
 and incline it to red ; fixed alcaline Salts have this effedt in a greater degree. 
 Solutions of green Vitriol, and other Chalybeate liquors, change infufions of 
 Rhubarb to an inky blacknefs ; a mark that this root is poffeffed of an aftrin- 
 gent quality. 
 
 In effedt Rhubarb ufed as a medicine difco vers, befides its mild purgative 
 virtue, a manifefl aftringency •, whence its ufe in laxities and debilities of the 
 vifcera, and in alvine fluxes. The powdered root adts much more effedtually 
 as a cathartic than infufions, tindtures, extradts or other preparations: It may 
 be taken to the quantity of a dram. 
 
 It is Angular of this root, that the fpirituous extradt does not purge, but 
 that the extradt made by water after fpirit does ; as if its purgative quality re- 
 fided chiefly in a combination of gummy and faline matter. Mr. Boulduc re- 
 lates, that twenty-four grains of the powder purge as much as an infufion of 
 an hundred and eight grains, and as much as feventy-two grains of the watery 
 
 , extradt ; 
 
 (e) Rhubarb — both forts equal in goodnefs ,] 
 There are fome differences in the qualities 
 of the two forts of Rhubarb : Perhaps one 
 may be beft adapted for fome purpofes, and 
 the other for others. The Eaft-India Rhu- 
 barb appears manifeftly the ftrongeft, and 
 the T urkey fort has mod of an aromatic fla- 
 vour. Tindtures drawn from both, with 
 equal quantities of redtified Spirit of Wine, 
 have nearly the fame tafle ; but oh drawing 
 off the menftruum, the extradt left from the 
 tmdture of the Eaft-India fort proves confi- 
 cerably the ftrongeft. The Eaft-India 
 
 Rhubarb is more folid and compadt than 
 the other, and feems to have been taken up 
 at a feafon when the root Is lefs watery : It 
 does not appear to have required fo much 
 care in the drying, as the pieces never have 
 a hole through them like thofe of the others : 
 From its greater folidity, it is lefs fubjedt to 
 decay in keeping. 
 
 The Rhubarb plant has of late been na- 
 turalized to our own climate : But trials 
 
 have not yet been made, how far the roots 
 railed among us, agree or difagree in qua- 
 lity with thofe of foreign growth. 
 
Plants and their Parts. 
 
 361 
 
 extrad, its purgative principle not being eafily taken up by water any more Rhubarb* 
 than by fpirit, and being in great part changed or deprived of its virtue during ' — -v— ■*’ 
 the evaporation. It feems as if this principle was in part volatile : Herman 
 obferves that in fome perfons, the bare fmell of Rhubarb opens the belly ; and 
 Borrichius, that even the diftilled water is not only of a naufeous tafte, but 
 purgative. 
 
 Some endeavour to improve the virtue of Rhubarb for particular purpofes, by 
 torrefadion : The powdered root is placed on an iron plate, over a gentle fire, 
 and kept continually ftirring with an iron fpatula, till it lofes its peculiar fmell, 
 and changes its yellow colour to a brown. By this means its purgative quality 
 is greatly diminifhed, and its aftringent one fuppoled to be increafed : The 
 preparation however is at bed an injudicious one, as all that can be expeded 
 from it may be obtained with greater certainty, by joining to Rhubarb a due 
 proportion of fome aftringent or corroborant of known efficacy, as Peruvian- 
 bark or Cafcarilla. It is obfervable of this root, that it tinges the urine of a 
 deep yellow or reddifh colour. 
 
 THE roots of certain Docks and fome other plants railed in Europe ap- yif 
 proach to Rhubarb in appearance, participate in fome degree of its medicinal Monks 
 virtues, and are ranked among the officinal fimples, under the names of Rhubarb. 
 M^nks Rhubarb and Rhapontic. The common Monks Rhubarb is the 
 root of the Lapathum hortenfe latifolium , C. B. broad-leaved garden Dock or Pa- 
 tience (/). The Rhapontic of the phyfick garden of Berlin, and which of all Rhapontic, 
 the forts comes the neareft to the true Rhubarb, is the Lapathum folio rotundo 
 alpinum, J . B. & Tourn. round-leaved mountain or garden Dock. 
 
 Sixteen drams of this root yielded with redified fpirit feven drams and a. 
 fcruple of extrad, and afterwards with water three drams and a half, five drams 
 and half a fcruple remaining undifTolved. On inverting the procedure, and 
 treating the fame quantity of the root firft with water and afterwards with fpirit, 
 
 I obtained ten drams two fcruples of watery, and one fcruple of fpirituous ex- 
 trad ; the refiduum weighing five drams and a few grains. 
 
 The extrads made at firft, whether by w'ater or by fpirit, contain the adive 
 matter of the Rhapontic, both the fecond extrads having little or no tafte* 
 
 The yellow colour of the root is more perfedly taken up by fpirit than by wa- 
 ter, and more concentrated in the fpirituous than in the watery extrad. The 
 fpirituous extrad is alfo ftronger in tafte than the watery : On firft tailing, 
 they both prove fweetilh, but loon after difcover a degree of pungency. 
 
 ARNICA SCH WEEDENSIS fomewhat refembles in its flowers yj|f 
 the Arnica formerly mentioned, and has by fome been miftaken for it. Ir is 1, 
 
 -TxR N I C A o 
 
 ( f ) Alonks Rhubarb.'] The roots of this 
 plant, though they have pretty much of the 
 appearance of true Rhubarb, come far fliort 
 of it in quality: they naufeate the ftomach, 
 and though given in double the dofe of 
 Rhubarb they lcarcely produce any evacua- 
 
 A 
 
 never* 
 
 tion. It is obfervable that the young fhoots 
 in the fpring approach in tafte to fome forts 
 of apples : Of late, they have been employ- 
 ed in that early feafon, as a fuccedancum 
 to apples for culinary purpofes. 
 
 a a 
 
Plants and their Parts. 
 
 neverthelefs a quite different plant, a fpecies not of "Doronicum but of After, 
 named by Tournefort After pratenfis autumnalh conyza folio. It differs alio 
 greatly in quality, being not at all emetic or purgative, but aftringent, and 
 hence recommended in alvine fluxes. Nor does it yield fo much foluble mat- 
 ter to watery or fpirituous menftrua : An ounce of the flowers gives hardly a 
 dram of rcfinous, and about two drams of gummy extradt. 
 
 TOR ME NT I L, ( Torment-ilia Sylveftris , C. B. is a low creeping plant, 
 ■with frnall indented leaves Handing feven together, and yellow tetrapetalous 
 flowers, growing fometimes in meadows, but chiefly in fandy and hilly places. 
 It is called Tormencil from its being ferviceable againft fluxes with 'Tormina or 
 Gripes-, from the number of its leaves it is named Heptaphyllum, Septfoil. 
 
 The root, which is the only part made ufe of, is {lender, never thicker than 
 the little finger, very knotty, irregular, and varioufly bent, externally of a 
 brown colour, internally reddifli with white or yellow ftreaks, of a fomewhat 
 aromatic aftringent tafte, with fcarcely any fmell. It is employed as a mild 
 aftringent and corroborant: By fome it has been fubftituted to Peruvian-bark 
 in the cure of intermitting fevers : By fome it has been mixed with a little eme- 
 tic Tartar as a fuccedaneum to Ipecacoanha in dyfenteries. 
 
 This root is extremely hard and compact, and does not readily part with its 
 adtive matter on digeftion either in water or in fpirit : It does however, by de- 
 
 grees, give out the whole of its virtue to both menftrua. The fpirituous ex- 
 tradt is much more ftyptic, and of a deeper red colour than the watery; not that 
 fpirit takes up more from the root than water does, but from its taking up lefs 
 of the inert matter, whence the adtive parts are more concentrated : An ex- 
 tradt made by fpirit after water is as inflpid as that made by water after fpirir. 
 
 From two ounces of the root cut in frnall pieces, I obtained by redtified fpirit 
 fix drams five grains of extradt, and afterwards by water two drams two fcruples 
 and a half; the refiduum weighing feven drams five grains. The fame quan- 
 tity, treated firft with water, gave nine drams and a half of gummy extradt, 
 and afterwards with fpirit only eight grains of a refinous matter; the refiduum 
 amounting to fix drams twenty-two grains. In diftillation, redtified fpirit 
 brings over nothing; the diftilled water difcovers a little of the aromatic tafte 
 of the Tormentil-roor, and a flight agreeable fmell, fomewhat like that of 
 Rofewood. 
 
 G A LL S are excrefcences found upon the Oak-tree, produced by an in- 
 fect, which wounds the young branches in the fpring, and depofites its eggs in 
 thepundture: The tear which iffues from the wound, gradually increafed by 
 acceflionsof frefh matter, forms a covering to the young infedt, which at length 
 eats its way out, leaving the Gall hollow. When the Gall has no perforation, 
 the infedt isfounddead within it. Sometimes alfo, after theefcape of its own, 
 it is occupied by other infedts. 
 
 There is a great variety of Galls, whitifh, yellowifh, greenifh, brownifh, 
 reddifli, greyifti and blackifh, frnall and large, round and irregular, light and 
 heavy, frnooth, and with protuberances on the furface. The frnall, blackifh, 
 ocotuberant, and ponderous, are the beft. Thefe are the produce chiefly of 
 
 the 
 
Plants and their Parts. 
 
 theTurkifh dominions, and brought immediately from Aleppo, Tripoli, and Galls. 
 Smyrna : Thofe of Europe are greatly inferior. u*— 'v— w 
 
 As ail the parts of the Oak-tree are notably aftringent, it is natural for this 
 excrefcence to polTefs that quality ; and in effed Galls are found to be one of the 
 itrongeft of the vegetable ftyptics: Hence they ftrike a deep black colour with 
 folution of Chalybeate Vitriol (See page 181.) and are employed in conjunction 
 with that Salt, preferably to other vegetables, for dying cloth black, and for 
 making ink; thefe are the principal ufes to which they are applied. They are 
 rarely ufed medicinally, unlefs as an external ftyptic, Monf. Reneaume, in 
 the French Memoirs for the year 1710, recommends them internally againft 
 intermitting fevers, in preference even to Peruvian- bark, as being free from the 
 bitternefs of that medicine, occafioning no heat, and not requiring to be given 
 in fo large dofes : It is proper to obferve however, that great caution is requifite 
 in the exhibition of ftrong aftringents in that diforder. 
 
 Extracts made from Gails, both by water and by fpirit, polTefs- the whole of 
 their aftringency, but the fpirituous extrad is ftronger and more difagreeable 
 than the watery. An extrad made by fpirit after water has no particular tafte* 
 but an extrad made by water after fpirit taites manifoldly faline, and exhibits 
 fome fmall Ihining particles of an adua] Salt. 
 
 Sixteen drams of Galls grolsly powdered, yielded with water fourteen drams 
 of extrad, and afterwards with fpirit only four grains ; the refiduum weighing 
 two drams. The fame quantity, treated firft with fpirit and afterwards with 
 water, gave twelve drams two fcruples of fpirituous, and four lcruples of wa- 
 tery extrad ; the refiduum weighed half a fcruple more than in the former 
 cafe. 
 
 GENTIAN Paid to be fo called from Gentius a King of Illyria who is xq 
 fuppofed to have firft difcovered it, grows in fome of the mountainous parts of Gentian 
 S witzerland, Hungary, France, &c. from whence the fhops are fuppiied with 
 the dried roots. Theleavesarefomewh.it like thofe of White-hellebore, the 
 flowers monopetalous and yellow ; whence the plant is named by John Bauhine 
 Gentiana vulgaris major ellebori albi folio , and by Calpar Bauhine Gentiana major 
 lutea. The root is externally of a brown colour, internally yellow, with a 
 pith in the middle not of the woody kind but rather more fpongy than the reft 
 of the root ; the older and larger the root, the more porous •, the younger and 
 flenderer, the more compad : The belt roots are thofe which are of a middling 
 lize and a lively yellow colour. 
 
 This root has alight not difagreeable fmell, and an intenfely bitter tafte. It 
 is an excellent ftomachic and corroborant : By fome it is greatly recommended 
 in intermitting fevers, and diftinguifhed by the title of European Kinkina. 
 
 The furgeons frequently make ufe of it in old wounds, ulcers and fiftulte ; not 
 fo much however, as fome pretend, from any peculiar quality of obtunding, 
 acrimonious juices, as from its imbibing moifture, and fwelling thereby, and 
 thus dilating the orifice or keeping the lips afunder, 
 
 Sixteen drams o! this root yielded with redified fpirit fix drams and a half 
 ol refinous extrad •, and afterwards with water three drams and a half of a 
 gummy one: The fame quantity, treated firft with water and then with fpirit, 
 
 A a a 2 gave, 
 
364 Plants and their Pa r t s. 
 
 Gentian, gave nine drams of gummy and only a fcruple of refinous ex trad : The refi- 
 W~v«-w duum in the firft cafe weighed fix drams, in the latter two fcruples more. 
 
 The extract made at firft by fpirit contains all the birternefs of the Gentian, 
 and is the moft active preparation of it : The gummy matter extracted after- 
 wards with water is infipid. The extrad made at firft by water is indeed very 
 bitter, but lefts ho than the fpirituous, both on account of its quantity being 
 
 larger, and a part of the bitter matter being ftill left in the root •, for the Refin 
 
 gained from the refidue difcovers a manifeft bitterncTs. In diftillation, fpirit 
 brings over nothing : The cl i 11 i 1 led water has a flight impregnation from the 
 Gentian, but too inconfiderable to deferve any notice {g). 
 
 XII. WHITE or Bastard Dittany, Diflawnus albus vulgo five fraxinella % 
 White C. B, grows in the mountainous parts of Italy, Elungary, produces irregu- 
 DiTTANY.lar polypetalous flowers, and leaves like thole of the Fraxinus or Afh-tree. In 
 C-’—v - — 1 the fhops we meet with the cortical part of the root, which is of a whitifh colour 
 
 and a bitter tafte without any fmell ; the inner, woody, infipid pith being 
 
 taken out. The fmall young roots, about the fize of a quill, are much the 
 ftrongeft. 
 
 This root contains a much larger proportion of gummy than of refinous 
 matter : Out of fixty drams, water takes up fix drams two fcruples and a half; 
 redified fpirit only four fcruples two grains : The matter left by fpirit gave 
 five drams two fcruples and two grains to water; but the matter left by water 
 gave to fpirit no more than half a fcruple. The extrad made at firft; by fpirit 
 is the moft adive preparation : The watery extrad is far lefts bitter. The di- 
 ftilled water has fome little tafte; thediftilled fpirit has no other tafte or fmell 
 than pure Spirit of Wine. This root has been ranked among the ftomachics, 
 alexipharmics, and anthelmintics but it does not promife, however, any great 
 virtue ( h ) . 
 
 IN 
 
 (g) Gentian.] The Gentian ufed among 
 us comes chiefly from Germany. Some 
 years ago, a quantity was brought over 
 which had an admixture of pieces of a diffe- 
 rent root, the ufe of which occafioned vio- 
 lent diforders, and in fome inftances death. 
 This poifonous root is readily diltinguifthed 
 from Gentian by its- being externally of a 
 paler colour, and internally not at all yel- 
 low, but white : Chewed, it difcovers no- 
 thing of the bitternefs of Gentian, nor any 
 other than a flightly pungent mucilaginous 
 tafte. 
 
 Phyficians were at that time at fome lofs 
 for a luccedaneum to Gentian ; and indeed 
 among the great number of vegetable bit- 
 ters, we fcarcely know of one that poffeffes 
 the valuable qualities of. this root, which is 
 not only a ftrong but an almoft ftmple fla- 
 vourjefs bitter, Chemiftry however can 
 
 eafily purify the other bitters, and bring 
 them to the fame ftate with that of Gentian : 
 It can diftipate their offenftve flavour, and 
 preferve the bitternefs unhurt. If the dry 
 leaves of common Wormwood be boiled in 
 water, and the decodtion boiled down to the 
 conftftence of an extradt, the difguftful 
 matter of the Wormwood will all, exhale in 
 the boiling, and may be caught and col- 
 lected by itfelf, whiift the extract proves 
 Amply bitter, as ftrong, as flavourlefs and 
 inoffenfive, as an extract made from Gen- 
 tiam This extract gives out its pure bit- 
 ternefs to rectified Spirit of Wine as well as 
 to water. 
 
 (h) White. Dittany. ~\ The root of this plant 
 yields no effential Oil in diftillation, but the 
 leaves a confiderable quantity : The Oil has 
 a ftrong unpleafant fmell, fomewhat of the 
 
 Tere- 
 
Plants and their Parts, 
 
 3 6 S 
 
 I N the two foregoing plants, the bitternefs is confined to the roots : In the 
 Lesser Centaury it is only the herb, or the part which arifes above ground, £~ ss E t 
 that is bitter. Centaury is fo called from Centum and Aurum , on account of its C ek rjav 
 excellent virtues; and agreeably to this derivation, it is named by the-Gerrrians v— — *■ 
 
 7 'auj end- gulden-kraut . The fpecies here intended is the Centaur him minus , C. B. 
 
 It grows chiefly in dry Tandy grounds, and if the feafon proves all'o dry, is ex- 
 tremely apt to fail : As in Tome fummers we meet with very little, it is proper 
 to lay in a dock in thofe years when it is plentiful. The leaves are (lender, fur 
 nifhed with three ribs like thofe of Plantane, but fmaller and narrower : There' 
 is commonly a bufh of leaves upon the ground, but on the dalle no more than 
 twelve, which (land in pairs. The flowers are numerous, and often cindered 
 together into the form of Umbels : They confiflof Angle, purplifh red, funnel 
 fhaped petala, which fliut in the night, and open in the day-time. The (hops 
 are generally fupplied with the herb in flower, tied up in bundles, though the 
 flowers have little or nothing of the bitternefs for which the plant is valued. 
 
 Thefe flowers, like other red ones, lofe their colour on being kept: It is 
 
 obfervable that the change begins in the lower narrow part of the flower next 
 the cup, and proceeds gradually upwards, the upper edge retaining its colour- 
 longed. The leaves of LefTer-centaury are almod Amply bitter, with very 
 little of any fmell or particular flavour: They are excellent ftomachics and cor- 
 roborants in intermitting fevers, cachexies, dropfies, (Ac. Maurice Hoffman 
 relates, in the Ephemerides nature curieforum, that he cured two hydropic cafes 
 with powdered Centaury alone, and hence gives the plant the name of Gen ti ana 
 hydro-pica. 
 
 The bitternefs is taken up both by water and by fpirit ; the tindure and ex- 
 trad made with the latter are the drongelt. An ounce of the dry tops yielded 
 with rectified Spirit three drams two fcruples of refinous, and afterwards with 
 water two drams one fcruple of gummy extrad; the refiduum weighed two 
 drams, or one fourth of the quantity of Centaury employed. Another ounce, 
 treated firfl with water, gave five drams one fcruple of gummy extrad, and 
 afterwards with redified fpirit two fcruples of Refin ; the refiduum weighing, 
 as before, jud two drams. The green colour of the herb refldes in the refin- 
 ous principle, being extraded by redified fpirit and not by water. In didilla- 
 fion, neither water nor fpirit receive any confiderable impregnation. 
 
 CARDUUS BENEDICTUS {Cnicus fylvejiris hirfutior five Car duus XIV 
 Benedidlus , C. B.) is another bitter plant, whofe bitternefs is confined chiefly toc ARDLJU 
 
 the leaves. Four ounces of dry Carduus leaves yielded with redified fpirit , „ 
 
 four drams and a half of refinous extrad, and afterwards with water fix drams 
 and a half of a gummy one, the indifloluble earthy part amounting to two ounces 
 and five drams. The fame quantity, on applying firfl water and afterwards 
 Spirit of Wine, gave ten drams of gummy extrad, and only one dram of 
 Relin. 
 
 The 
 
 Terebinthinate kind, like that of the herb take fire on the approach of a. candle, and 
 itfelf. It is faid that when the herb is in form a large lambent flame which fpreads, 
 vigour, its effluvia in very hot dry weather, all over the plant. 
 
366 Plants and their Parts. 
 
 Carduus. The frefh plant ha? a weak not agreeable flavour, which arifes in diftilla- 
 L— -v— — f tion with water, efpecially if the Carduus is previoufly fermented for a little 
 time : In drying, it lofes its flavour, and in this ftate gives over nothing. The 
 expreiTed juice, duly depurated and evaporated to the thicknefs of a fyrup (See 
 page 279.) yields, on Handing, faline cryftals, approaching to the nature of 
 Tartar. 
 
 XV. THE frefh leaves of Ho rf. hound (Marrubium album vulgar e , C. B.) have 
 Horkhoukd a bitterifh tafte, v/ith a peculiar not difagreeable fweetifh fmell, refembled by 
 ibme to that of Citrons, by others to that of Mufk, but which feems to ap- 
 proach nearer to that of redified Spirit of Wine. 
 
 Their fmell is diffipated in drying, and elevated by water in diftillation, but 
 not by pure fpirit •, the diftilled water gives no appearance of any oily matter. 
 The bitternefs remains uninjured in both the extracts •, the fpirituous is much 
 the ftrongeft, and in fmalleft quantity j it poftefies the true fpecific tafte and 
 flavour of the herb, together with its green colour. 
 
 An ounce of the dried leaves yielded four drams and a half of watery, and 
 .aftei wards half a dram of fpirituous extrad : Rectified fpirit applied at firft ex- 
 tradit'd two drams and a half, and water afterwards two drams and a fcruple : 
 The refiduum in the firft cafe weighed three drams, in the latter three drams 
 ten grains. 
 
 X\ r [ W ORM SEED, Semen lumbri corum, femen contra vermes , fo called from its 
 WopvMseed. ufe againft worms, is a bitter feed, faid by fome to be the produce of China, by 
 w***-y — — > others of the Holy Land; whence its names Semen fina or ana. Semen fan slum, 
 Sementina , Santonicum. 'S he plant which affords it is not as yet known with any 
 degree of certainty : By fome it is referred to the genus of Wormwood, by others 
 to chat of Southernwood, and by others to that of Lavender Cotton. Tavernier 
 relates, that he found the plant growing in fields in the province ofBoutan; that 
 the feeds when ripe, fall off" upon the flighted touch, and are fo light as to be 
 blown away by the wind, and that they are gathered by applying balkets to the 
 plant. As brought tous, they are commonly mixed with a notable quantity of 
 irnall bits of (talks and leaves, which cannot be feparated by winnowing, on ac- 
 count of the great lightnefs of the feed itfelf, Ettmifiler fuppofes that the Worm- 
 feed of the (hops is no other than the feeds of Taniy ; but from thofe it is entirely 
 different in its figure and appearance as well as in its fmell and tafte : The feeds 
 both of Tan fy and other plants, however, are not unfrequently mingled with 
 it. Large quantities are imported immediately from Venice: I have there 
 feen fome of a fine green colour, which is held a mark of its frefhnefs, though 
 I have been aflured, that the dealers have a method of impregnating the old 
 decayed yellow feeds with the admired colour. Thole commonly met with are 
 of a yellowifh-green colour, a bitter tafte, and a very difagreeable fmell. 
 
 Water extracts more from thefe feeds than redified fpirit; but the fpirituous 
 extrad is far ftronger than the watery, the former retaining the whole of the 
 fmell and tafte of the feeds, whilft in the latter very little even of their tafte is 
 preferved. An ounce of the befc Wormfeed, digefted in frefh parcels of redi- 
 fied fpirit, fo long as it continued to give any tinge to the menftruum, yielded 
 
 on 
 
Plants and their Parts. 
 
 on infpiflating the tinctures, three drams thirty-three grains of refinoos extras A Vo?r ' 1SFED - 
 after which, it gave with water, five fcruples and a half of a mucilaginous one. 
 
 On treating another ounce firft with water and then with fpirit, I obtained four 
 drams and a fcruple of gummy extract, and only twenty-eight grains ofRefin. 
 lire refiduum in the firlt cafe, weighed two drams thirty-eight grains ; in the 
 latter, two drams fifty-four grains. 
 
 In difiillation, re&ified fpirit brings' over nothing. The difli lied water taftes 
 and fmells of the feeds, but lcarcely exhibits a fingle particle of Oil, though a 
 whole pound be committed to difiillation at once. The Oleum cina therefore, 
 which has long been kept in the [German] (hops, cannot be a genuine efTentia! 
 
 Oil diftilled from Wormfeed. 
 
 CONTRAYERVA is the root of a climbing fpecies of Pafiion-fiower, 
 with leaves fomewhat refembling a horfe-fhoe ( Clematis pajfionalis folio bifido Mo- q )ntr ’ a 
 rifon ) growing in the Spanifh Weft- Indies, particularly in Peru and Mexico. 
 
 The leaves of the plant are faid to be poifonous, and to be employed by the t E ^ VA * , 
 Indians for poifoning darts : The root is held an antidote to this and to other 
 poifons, and from this fuppofed virtue, the Spaniards give it the name of 
 Contrayerva, that is, Counterpoifon. The phyficians of our own country ex- 
 pert from it no fuch virtues; but they frequently exhibit it as a diaphoretic 
 and alexipharmac in low fevers. 
 
 This root is about the thicknefs of the little finger, feldom more, thicker at 
 one end than the other, very crooked, knotty, full of fibres, extremely firm 
 and hard, almoft of a horny texture, of a reddifh- brown colour on the out- 
 fide, and fomewhat whitifh or greenifh within, of a flight kind of aromatic 
 fmell, of an aftringent tafte, not remarkably pungent, leaving a peculiar fla- 
 vour in the mouth. Extracts made from it both by water and fpirit are confi- 
 dcrably pungent : The watery extraft is the leaft fo, and hence may be ufed 
 in fome fevers where the fpirituous tineftures or extracts would heat and ftimu- 
 late too much. Neither the diftilled waters nor the fpirits have any remark- 
 able impregnation from the Contrayerva. 
 
 An ounce of the powdered root yielded with water three drams and half a 
 fcruple of extradt, and afterwards with fpirit only feven grains : Rectified fpi- 
 rit, applied at firft, took up five fcruples and two grains from an ounce; after 
 which, water extradted near a dram. 
 
 WHEN Contrayerva is fcarce, Swallow-wort root is fometimes ufed xVTIf 
 mitsftead. Swallow-wort, Vincetoxicum> afclepias, hirundinaria (Afdepias ^^Swallow-- 
 flore, C. B.) grows wild in woods, and produces white flowers in July and wort. 
 Auguft : It has a number of flender roots or fibres hanging from a fomewhat w** s y*'^ 
 larger one, of a not dilagreeable fweetifti tafte accompanied with a kind of bit- 
 terifhnefs, and a flight pungency, when frefh of an unpleafant fmell, which is 
 in good meajure loft in drying. 
 
 The juice of the frefh root changes the colour of blue paper to a reddifh, 
 and thus difeovers a degree of acidity : When dry, it gives no mark of any 
 acid, unlefs committed to diftillation in an open fire, in which cafe, like other 
 vegetable matters, it gives over an acid phlegm or fpirit. Extracts made from 
 
 this 
 
368 
 
 Plants and their Parts. 
 
 Swallow- this root both by water and vinous fpirits have an agreeable fweetilh tafte. The 
 wort, watery extract is ftronger in tafte than the fpirituous ; and even the watery 
 L extrabl made alter the abtion of fpirit is ftronger than that made by fpiric 
 after the action of water; hence water appears to be the moft proper men- 
 ftruum in regard to the quality as well as the quantity of the produft. 
 
 From fixteen ounces of the root I obtained by water five ounces, and from 
 the remainder, by fpirit one ounce. Another pound, treated firft with fpirit, 
 gave only four ounces : From the remainder water extracted two; the indif- 
 ioluble earthy matter amounting in both cafes to ten ounces or five eighths of 
 the root. What arifes in diftillation, either with water or with fpirit, is entirely 
 inconfiderable. 
 
 XIX. 
 
 Valerian 1 . 
 
 VALERIAN root is fometimes employed in the fame intentions as the 
 two foregoing, but its principal ufe is as an antifpafmodic : There are fundry 
 inftances of epilepfies cured by the powder of this root given from a fcruple to 
 a dram and a half in white Wine, a laxative being premifed. In the warmer 
 •parts of Europe, Italy, Spain, Portugal, &c. the garden Valerian ( Valeriana 
 kcrtenfis , phu folio olufatri diofccridis C. B. Valeriana odor at a radicej . B.) is chiefly 
 made ufe of ; but in our colder climate, this garden fpecies proves far inferior 
 in quality to the wild fort, Valeriana fylvefris major, C. B, 
 
 The leaves of wild Valerian have a bitterifh fubfaline tafte, but no fmell : 
 Their juice changes blue paper confiderably red, a mark that they contain an 
 efteiuial Salt of the acidulous kind. The root when largeft, is about the thiek- 
 nels of the finger, but in general much thinner, of a brownifh-grey colour on 
 the out fide and paler within, knotty, with numerous matted fibres, of a pun- 
 gent, aromatic, bitterifh, fomewhat ftyptic tafte, and a ftrong difagreeable 
 i'mell, approaching to that of Indian Nard, and in fome degree to that of Vir- 
 ginian Snakeroot, to which Valerian root has frequently been employed as a 
 iuccedaneum. The fibres are ftronger in fmell and tafte than the tuber- 
 ous part of the root: A good deal of care is requifite to waft) and clean them 
 from the earth which (licks among them. 
 
 An ounce of the dry root, thoroughly cleaned, cut and bruifed, yielded 
 with rectified fpirit three drams and fix grains of refinous extradf, and after- 
 wards with water one dram and fourteen grains of a gummy one : Another 
 
 ounce, treated firft with water, gave four drams twenty-one grains, after 
 which rectified fpirit extracted only five grains: The indifioluble refiduum 
 weighed, in the firft cafe three drams forty grains, in the latter three drams 
 thirty grains. The diftilled fpirit is (lightly, and the diftilled water pretty 
 ftrongly impregnated with the fmell of the Valerian, but no feparable Oil is 
 obtained. The moft ablive preparation is the fpirituous extradl, which is con- 
 fiderably more pungent and more bitter than the watery, and contains all the 
 ufe ful matter of the root concentrated into a fmall volume. 
 
 The root of the (mailer wild Valerian ( Valeriana palujlris minor „ C. B.) is 
 nearly fimilar to the foregoing, but weaker The principle in which its odour 
 refides, is moregrofs and ponderous, no part of it being elevated in diftillation 
 by Spirit of Wine. The diftilled water exhibits iome appearance of oilynels. 
 This root appears alfo to contain fome portion of an Oil of the expreflible kind, 
 i whence 
 
Plant s and their Parts. 369 
 
 whence the extract made by fpirit after water proves undtuous and rancid. An Valerian. 
 extradt made by water after fpirit is in tafte faline : The fpirituous extradt made v — — v — — * 
 at firft has an agreeable fmell and an aromatic bitter tafte ; the watery is in 
 tafte weaker, and in fmell offenfive. An ounce of the root yielded with water 
 four drams and a half, and afterwards with redtified fpirit ten grains: From 
 another ounce I obtained, by applying fpirit at firft, two drams two fcruples ; 
 and afterwards by water two drams and half a fcruple: The refiduum in the 
 
 firft cafe weighed three drams one fcruple, in the latter fomewhat id's. 
 
 THE roots and feeds of Peony are reckoned alfo fpecific antepileptics, but 
 their virtues are perhaps rather imaginary than real. The red Angle flowered p £ Q . 
 Peony (Pronin folio nigricante fplendido qu^mas, C. B.) has been fuppofed to be , f , * 
 the moft efficacious, though at prefent the fingle and double flowered forts are 
 for the moft part taken indifcriminately. 
 
 The roots of Peony are pretty thick, tuberous, of a brown colour on thext 0<j£j . 
 outfide and a pale reddifh within : When frefh, they have a fomewhat pungent 
 fweetifh tafte, accompanied with a degree of bitterilhnefs. Hermann fays they 
 have no fmell : They have a weak, but a very fenfible one, not refembling 
 that of any other fubftance I know of. 
 
 An ounce of the dry roots yielded with water four drams and a fcruple of 
 gummy extract, and afterwards with redtified fpirit only half a fcruple ol Re- 
 ft n : The refiduum weighed three drams and a half. Redtified fpirit applied at 
 firft extradted, from an ounce, two drams and a half; from the remainder, 
 water took up two drams, leaving as before, three drams and a half undii- 
 folved. 
 
 The fpirituous extradt is of all the preparations the ftrongeft both in tafte and 
 fmell : On firft rafting, it difcovers a remarkable fweetnefs, which is followed 
 by a difagreeable bitternefs, like that of the root in fubftance : The fpirituous 
 extradt made after water has the fame kind of tafte in a lower degree. The 
 watery excradts have only a flight fweetifhnefs : Thefe are *of a darker and 
 browner colour than the fpirituous. In diftillation, redtified fpirit brings over 
 nothing: The diftilled water fimells and taftes confiderably of the Peony. 
 
 The flower of Peony is large, likeaRofe: The fruit confifts of three, four, Flowers, 
 or five oblong horned pods, which open fpontaneoufly when the feeds are ripe, 
 
 The feeds are at firft of a reddifh colour, which deepens into a Garnet red. Seeds, 
 then changes to a violet, and at laft to a bright glofiy black : Under the co- 
 loured fheli is contained a white kernel, which taftes fomewhat like peas. 
 
 An ounce of the hulked feeds, boiled with water, gave two drams of ex- 
 tradt, of an oily fmell and a iweetifh tafte : The remainder, treated with redti- 
 fied fpirit, gave half a dram of an inodorous bitterifh extradt: The indiftoluble 
 part weighed five drams and a half. On inverting the order of applying the 
 menftrua, I obtained by fpirit five fcruples from an ounce, and afterwards by 
 water two fcruples and a half, the refiduum weighing as before five drams and 
 a half : The fpirituous extradt appeared very undtuous or oily, tafted and fmelt 
 not difagreeably, and feemed to be the moft adtive preparation : The watery 
 was both in fmell and tafte very naufeous, like rancid Oil. In diftillation, fpi- 
 rit brings over nothing, and water exceeding little. 
 
 B b b 
 
 SCRO- 
 
37° Plants and their Pa r t s. 
 
 XXI. SCROPHULARIA, Figwort, ( Scrophularia nodofa fcvtida , C. B. ) is fo 
 Scrophu- called from the fuppofed virtues of its root againft fcrophulous diforders. An 
 
 laria. ounce of the dry root, digefted and boiled in feveral frefh parcels of water, 
 
 v — ) yielded upon evaporating the decodions, five drams and a half of extrad ; 
 
 after which, redified fpirit extraded but five grains, two drams and a half re- 
 maining undiffolved. On inverting the order of applying the refpedive men- 
 ftrua, the fpirituous extrad weighed four drams, the watery one dram and a 
 half, and therefiduum as before, two and a half. 
 
 The extrad made by applying water firft, was in tafte confiderably fweer, 
 and not di (agreeable •, the firft fpirituous extrad was ftronger and fomewhat 
 bitter: The watery extrad made after fpirit had no tafte; the fmall quantity 
 of refinous matter, which fpirit extraded after the adion of water, was quite 
 difagreeable and fomewhat rancid. The diftilled water has very little tafte or 
 fmell, the diftilled fpirit none. 
 
 XXII. P O LY P O DY ( Polypodium vulgar e , C. B.) is a plant fomewhat approach- 
 Polypody, ing in appearance to thofe of the Fern kind, growing upon old Oaks and other 
 
 ~ "v— ^ trees, asalfo upon old walls and rocks: It has no flowers ; the feed is a fine 
 duft lying on the back of the leaves. The roots are numerous, irregular, full 
 of fibres and knots, fuppofed to refemble the feet of an infed, whence the name 
 Polypody, i. e. Many-feet: They are externally of a brown colour, internally 
 of a fine yellowifii green, eafy to break, of a fweet but fomewhat naufeous 
 tafte, without any fmell : Some of them difcover a degree of acrimony and 
 aftringency. 
 
 An ounce of the root, freed from the fibres, yielded with redified fpirit 
 three drams, and afterwards with water one dram of extrad : Another ounce, 
 treated firft with water, gave three drams two fcruples, and afterwards with 
 fpirit only one fcruple ; the indiftoluble earthy part amounting in both cafes to 
 four drams, or half the weight of the root. The fpirituous extrad is manifeftly 
 oily ; and on this oil, which is of the expreflible and not of the efiential kind, 
 the naufeous tafte of the Polypody feems to depend : The fpirituous extrad is 
 extremely naufeous and rancid, the watery much more agreeable. In diftilla- 
 tion, nothing confiderable arifes either with water or with fpirit. 
 
 This root is fometimes given in obftrudions of the breaft and vifcera, and 
 fuppofed to be gently laxative, but it poffeffes that virtue in fo low a degree, 
 that two or three drams have fcarcely any effed. 
 
 XXIII. B O R O N I C U M or Leopard’s-bane, is another root of a fweet but un- 
 Doronicum. pleafant tafte, accompanied with a bkteriftinefs and aftringency, and whofe 
 qualities are but little known. The plant, called by Cafpar Bauhine Doroni- 
 cum radice dulci, grows wild in ftony grounds, in Italy, Auftria, Switzerland, 
 Languedoc and fome other parts of Europe. The root comes chiefly from 
 Italy, whence the name Doronicum Romanum : It is jointed, not very large, 
 furnifhed with long fibres, of a yellowifii colour on the outfide and white 
 within.. 
 
 prom 
 
Plants and their Parts. 371 
 
 From two ounces of the dry root v/ere obtained by water fourteen drams oFDoronicum. 
 
 extrad, and afterwards by fpirit five grains, only two drams remaining undif- ■ — ■**■ ; 
 
 foived. The fame quantity yielded, with fpirit at firft, four drams and a half, 
 and afterwards with water nine drams, the refiduum amounting to two and a 
 half. The firft fpirituous extract is in tafie much ftronger and fweeter than 
 the watery, though the watery contains alfo nearly all the adive matter of the 
 Doronicum. The diftilled water has fome iittle fmell and tafte ; the diftilled 
 fpirit has neither. 
 
 This root is by fome accounted poifonous, by others alexipharmac. It is 
 moft commonly fuppofed to be poifonous only to quadrupeds ; or if it is noxi- 
 ous to men when frefh, to be innocent when dry. 
 
 THE roots of the common garden Iris or Flower-de-luce {Iris vulgaris vio - XXIV, 
 l ace a five purpurea fylveftris , C. B.) are when frefh ftrongly purgative: I have Iris. 
 
 known unfavourable confequences even from their external ufe as a cofmeticv 
 By drying, they lofe their virulence, fo as fcarcely to purge at all. 
 
 THE dry roots of the Florence Iris or Orris {Iris alba for entina, C. B.) are Florence Or- 
 entirely mild, and faid to be a medicine of good fervice in diforders of the ris " 
 bread. They have a pleafant fweet fmell refembling that of Violets, and 
 hence are employed in fweet- fcented powders, for flavouring liquors, (s ?c. 
 
 The diftilled water fmells a little of the root, but exhibits no appearance of 
 Oil : The diftilled fpirit alfo has fome flight fmell. The ftrongeft prepara- 
 tion both in fmell and tafte, is the fpirituous extrad, this containing nearly all 
 the adive parts of the root concentrated into a finall volume. An ounce of 
 the root yielded a dram and feventeen grains of fpirituous, and afterwards a 
 dram and forty grains of watery extrad : Water applied at firft extraded from 
 the fame quantity three drams, and fpirit afterwards only eight grains. The 
 extrad made by water at firft both taftes and fmells of the Orris, though not 
 near fo ftrongly as the fpirituous. 
 
 T FIE flowers of St. John’s Wort ( Hypericum vulgare , C. B.) abound with XXV 
 Refin : They difcover even to the touch an unduous, refinous, balfamic Hyprf i 
 juice. An ounce yielded with redified fpirit juft half an ounce of extrad. CUM ^ 
 They contain however fo much mucilaginous matter, as to render nearly all » 
 the Refin, or at leaft all its adive parts foluble in water : An ounce yielded 
 five drams of watery extrad, in tafte aftringent and difagreeable. Water ap- 
 plied after fpirit, extraded two drams ; fpirit after water, only two fcru pies. 
 
 The indifloluble earthy part weighed in the firft cafe two drams, in the latter a 
 fcruple more. In diftillation, nothing confiderable arifes either with water or 
 fpirit. It is obfervable, that the firft tindure made in redified fpirit is of a 
 fine red colour-, but that when this is poured off, and the flowers digefted in 
 a frefh parcel of fpirit, they tinge it greenifh— Thefe flowers are fuppofed to 
 be refolvent, vulnerary, nervine: The fuperftition of former times afcribed to 
 them alfo extraordinary anddaemoniacal powers. 
 
 B b b 2 
 
 THE 
 
37 2 
 
 Plants and their Parts. 
 
 XXVI. TH E flowers of the Golden Stvechas or yellow Caffidony (. Elkhryfum 
 Goi.p i locks .feu SLecbas citrina angujti folia , C. B .) are remarkable for preferving their frefia 
 yellow colour in long keeping: Some have a plpafant mufky fmell, others 
 
 have none: Their take is pungent, aftringent and bitrerifn. An ouncevielded 
 three drums forty-four grains of watery, and afterwards fifteen grains of l'piri- 
 tuous excradl, half an ounce remaining undiffolved. On inverting the order 
 of applying the menftrua, the fpirituous extract weighed two drams forty-four 
 grains, the watery one dram three grains, and the refiduum four drams twelve 
 gr ains. The extracts made firft, either by water or fpirit, are aftringent ; the 
 ipirituous is the flrongeft. The difti 1 led water has feme flight flavour of the 
 flowers, the fpirit fcarcely any. — - — Thefe flowers are ufed for ftaining hair yel- 
 low, and medicinally as an aftringent, anthelmintic, &c. They likewife give 
 a yellow dye to wool. 
 
 XXVII. T E A is the leaf of an oriental ftirub, called by Cafpar Bauhine Chaa herba in 
 Tea. Japonic., by Breynius and Ray The Sinenfium five t'sj a Japonenfibus, by Kaempfer 
 \ Then frutex, &c. “ the Tea-ftirub, with leaves like thole of the Cherry- 
 
 “ tree, flowers like thole of the Dog-role, and a fruit compofed of one, two, 
 “ and, for the moft part, three berries.” The plant comes the neareft, in its 
 general appearance, to the Dog-rofe, but is fmaller, and without prickles. 
 Dr, Cleyer, who lived fome time in the Eaft-Indies, lent feveral lpecimens to 
 Simon JPaulli in Denmark, and Dr. Mentzel in Berlin ; of which figures may 
 be feen in the Aft a Haffnienfm and the German Ephemcrides. 
 
 Only one fpeeies of the Tea-plant is as yet known; the differences in this 
 commodity, as brought to us, proceeding from a difference in the climate, foil, 
 age, method of collection and curation : Some indeed mention a Angle and a 
 double-flowered fort, but of this we have no certainty. It is laid by fome to be 
 a native of China only, by others both of China and Japan : Others add a. 
 
 third country, Siam, and fuppole, not without probability, that the Japonic 
 , name ffia is derived from thence. Thus much is certain, that at prefent it is 
 
 regularly cultivated in different provinces of Japan and China, but does not in 
 all prove of equal goodnefs : Fifien in Japan, and Nankin in China, produce 
 the beft. 
 
 The Chinefe plant whole fields with Tea •, the Japanefe only the borders of 
 fields fronting the South. From fix to a dozen of the berries are planted toge- 
 ther (as they are very apt to fail) and covered with dung and earth : It is laid, 
 that they are three years in coming up, and that they are carefully covered in 
 die winter with ftraw. After a certain number of years, which Kaempfer li- 
 mits between feven and ten, appear the admired leaves : After thefe have been 
 ' gathered, the plant is either cut down, and new fhoots expected from the 
 root, or extirpated and renewed from feed. As the berries are extremely apt 
 to fpoil, infomuch as to require being planted quite frefti in their native cli- 
 mate, and as the fhrub does not bear being removed entire, there are little 
 hopes of our being ever able to introduce it into Europe : Nor would it, pro- 
 bably, in thefe colder climates, prove equal in quality to the Chinele, fince even 
 in China and Japan it proves greatly different in different provinces. 
 
 If: 
 
'Plants and their Parts. 3 73 
 
 If the winter does not prove very fevere, the leaves come forth in February, T e a. 
 and about the end of this month, or the beginning of next, the ftrft colledlion 1 
 
 is made. Thefe early tender leaves are the true Imperial, called alio impro- 
 perly b!oom'Ya?L\ but they cannot be the fort to which the Dutch give than 
 name, as being fold upon the foot, to the princes of the country, ior vaftiy 
 more than the common Bloom-tea is fold for in Europe. About the end of 
 March or the beginning of April, the fecond and molt confiderable crop is 
 gathered: A large linen-cloth is ftretched over the bulb, to defend from the 
 lun not only the gatherers, but the leaves themfelves, left they Ihould dry too 
 raft, and lofe their flavour. The leaves are picked one by one, fo curioully, 
 that the moft induftrious can fcarcely colledt four pounds in a day. They are 
 commonly divided into four fortments ; of which the fmaller upper ones are 
 the beft, the larger lower ones the worft, and the intermediate of a middling 
 goodncfs. The third collection is in the end of April or beginning of May: 
 
 This likewife affords different forts, which are thofe moftly brought into Eu- 
 rope : The very beft fort which we meet with here, called Imperial Tea, is 
 but the lower leaves of the fecond crop. About the end of May, all the leaves 
 on the plant are gathered promifeuoufly, without forting, and fold about the 
 ftreets to the poorer people; thefe being the worft of all, and unfit for being 
 cured in the Chinefe manner. 
 
 Thejapanefe, who lwallow their Tea in fubftance along with its infufion, 
 dry it haftily in iron pans over the fire, and grind it into powder. The Chinefe, 
 on the other hand, are very curious of preferving the leaves entire, and roil 
 them up that they may be lefs apt to break in carriage. So foon as gathered, 
 they are brought into an apartment furnifhed with a number of little furnaces, 
 each of which is covered with a fmooth iron plate. The leaves are fpread upon 
 the plates, and kept rolling with the hands, in one direction, till they become 
 moderately dry, and begin to curl up about the edges, when they are immedi- 
 ately fwept off upon tables covered with fmooth clofe mats, on which one per- 
 fon continues to roll them over and over, whilft another fans them, that they 
 may cool haftily, and retain the curl. This procefs is repeated two or three 
 times or oftener, according as the leaves are dilpofed to unbend upon (landing. 
 
 If exficcated without artificial heat, or by a very foft one, they rarely take the 
 curl, and never hold it. 
 
 Meifter relates, that the leaves are put into a hot kettle juft emptied of boil- 
 ing water ; and that in this they are kept clofely covered till cold, and then 
 committed to the hot plates : According to Lemery, they are held in the 
 fleam of water. But Kaempfer mentions nothing of all this ; and if any fuch 
 thing is pradtifed in regard to Green-tea, I fhould imagine it to be only for 
 foftening fuch of the leaves as have happened to grow too dry, and would 
 break in the curling. Boerhaave pretends that the preparers employ green 
 Vitriol for improving the colour of the Tea : This I judge to be falfe, becaufe 
 green Vitriol, infteaci of heightening the green colour of Tea, changes it to 
 an inky blacknefs. 
 
 Thus much of the Green-tea. With regard to Bohea, I have not been able 
 to meet with any fatisfadlory account, either in books, or from the communica- 
 tion of merchants ; of both which, great numbers have been confulted. Kasmp- 
 
 i feiv 
 
374 Plants and their Pa r t s. 
 
 Tea, fer, and Dr. Cunningham, phyfician to the Englifh fettlement at Chufan, 
 
 — v J affirm, that it is the leaves of the firft collection ; but this muft certainly be a 
 
 miftake, as all the travellers agree that none of the firft crop is brought into 
 Europe, but that it is all referved for the princes of the land, and fold at an 
 immenfe price in China itfelf ; whereas Bohea comes over in large quantity, 
 and is cheaper than the fecond and third crops, if not than the fourth alfo. 
 Poffibly a particular kind of Bohea is made from the firft crop, for the ufe of 
 the nobility ; and our Bohea, prepared in imitation of that, from the third 
 and fourth collections, or perhaps from the earlier growths alfo in thofe pro- 
 vinces where the plant does not come to fuch perfection as to afford a good 
 Green-tea, The dark-brownifh colour, and Rofe flavour obferved in this 
 kind of tea, I hold, with Sigefbeck, to be artificial: The method of curation 
 defcribed by Meifter,' which certainly is in general not praCti fed for the Green, 
 probably is for the Bohea, which receives, perhaps, in the kettle, both its 
 tinCture and its flavour. This at leaft is certain, that by a fimilar procefs good 
 Bohea may be made among ourfelves ; a fpecimen of which I have exhibited 
 to a numerous audience. Some of the dealers in this commodity, in England, 
 are not ignorant that certain European leaves, particularly thole of the Dog- 
 rofe and Cherry-tree, may be fo coloured and prepared, as to pafs for good 
 Bohea. But I forbear to fay any thing further of this manufacture, left a 
 handle fho'uld be given for new abufes. 
 
 The Japan Tea has been obferved to be of a clearer green colour than the 
 Chinefe, and to have its leaves fmaller ; but which of the two is the belt has 
 not hitherto been determined, fome preferring the one, and others the other : 
 This controverfy does but little concern us, the Chinefe being the only one 
 brought into Europe. In China, Tea is divided into a great number of diffe- 
 rent fortments : There are fixteen or twenty of the green leaves, from the diffe- 
 rence in the collection only ; and thefe are further multiplied, when the leaves are 
 dry, by picking out fuch as have mifcarried in the preparation. Among us, there 
 are three principal kinds of green, and five of Bohea : From what province they 
 are brought, of what crop they are the produce, and to which of the Chinefe 
 forts they belong, is unknown : They have all names, but thefe are merely arbi- 
 trary, and ferve only for the conveniency of the dealer. The belt of the Green- 
 teas is called Bing, Imperial and Bloom-tea, Thea imperialis folio amplo laxo of 
 Dale : The fecond be ft, Hyffon , Thea viridis optima folio oblongo Dal : The third 
 or word, Singlo , Theaviridis folio minor e Dal. Of Bohea {Thea fufca folio ad 
 nigredinem vergente ) the forts are. Ordinary, Pecco, Congo, Camho, and 
 Souchong ; of which the firft is the worft, and the laft the beft. 
 
 The Chinefe are extremely curious and cleanly in every branch of the Tea 
 manufacture. They gather the leaves, as I have been well aflured, with 
 gloves made of a thin kind of leather. The workmen employed in the curation 
 are reftrained, for a fortnight before, from flatulent foods, and whatever might 
 endanger communicating any ill flavour. The Tea, when cured, is packed 
 up in large veffels made of a mixture of Lercl and Tin called Calin, or in 
 wooden cheffs lined with this compofition, or in cannifters of tinned plates 
 foldered with the fame, fo tight, that they may be kept occafionally under 
 water. 
 
 As 
 
Plants and their Parts. 37 
 
 As Toon as Tea became known in Europe, with its ufes among the Chinefe, Tea. 
 
 all the European nations thirfted after it. Its great price at that time confined 
 
 it to the rich, whence the learned were induced to examine the European 
 plants, with a view to difcover a cheap fuccedaneum to it. The moft cele- 
 brated of our fubftitutes is Veronica , on which Hoffmann and Joh. Francus have 
 written particular differtations. The leaves of the red Whortie-berry and Rofe 
 bufh are at prefent in greater efteem, and come nearer to the taffe of the true 
 Tea than any of the other plants that have been employed for this purpofe, as 
 Betony, Nettles, Agrimony, Coltsfoot, Eyebright, Strawberry, Scabious, 
 
 Cowflips, Golden-rod, Cherry-tree, Peach-tree, Wall-rue, fharp leaved Plan- 
 tane, Sanicle, Liverwort, Lungwort, Brankurfme, Balm, Sage, Rofemary, &c. 
 
 I admit, with the recommenders of thefe plants, that they are pofieffed of con- 
 fiderable virtues, greater in particular cafes, than any that Tea can pretend 
 to •, yet ff ill they want the chief excellence of Tea, that of being a diluent al- 
 moft univerfally acceptable. 
 
 Some pretended to have difcovered the oriental Tea itfelf in Europe or Ame- 
 rica. The firft of thefe was Simon Paulli, who obftinately maintained that 
 Tea was no other than the Chamaleagnus or Dutch Myrtle, but was refuted by 
 feveral botanilfs in Europe, and by the fpecimens fent by Dr. Cleyer. The 
 next was Father Labat, who in his voyages to America, relates, that in Mar- 
 tinico there grows a plant called wild Tea, agreeing in all refpedts with the 
 China fort, except that it has not fo much of the Violet fmell “ for in every 
 “ other refpect, he fays, it is affuredly the fame thing.” He adds further, 
 that he had procured Tea-feeds from the Eaft-Indies, and raifed the plant in 
 America. That he was miftaken here (as he often was in botanic matters) is 
 obvious from his own account : His feeds were fmaller than Poppy feeds, 
 
 whilft thofe of Tea are a kind of large nut or berry : His flowers had each but 
 four ftamina, whilft in one of the Tea-flowers Ksempfer counted two hundred 
 and thirty. The plant is no other than that called in England Weft- India 
 Tea, Lyfimachia purpurea a finis Americana , procumbens , anonidis venue frutefcentis 
 folio fingulari glabro of.Plukenet, found plentifully by Sir Hans Sloane about 
 Spanifh-Town in Jamaica. About twenty years ago there was another pre- 
 tended difcovery of Tea in the imperial dominions : But this like the others, 
 when examined by a botanift, was found to be a quite different plant, the 
 Botrys ambrofioides mexicana of Calpar Bauhine. The jefuits have at times made 
 great noife with this plant, under the name of Roman Tea. I fhall here add 
 one more kind of Tea, ufed lately in France: When I was in Paris, about 
 the year 1718, Tea and Coffee being common liquors, thofe who affebted 
 diftinbtiqn drank nothing but Apalacbine, fo called from the American terri- 
 tory of which it is the produce : It is the leaf of a tree fomewhat refembling the 
 Almond, called by the natives Caffme, by Hermann Euonymo adfinis athiopica? 
 fempervirens, frudhi globofo fcabro, foliis falicis, rigidis, f err at is. We fhall now 
 drop the counterfeits, and return to the true Tea. 
 
 The Oriental Tea, as we have already feen, is of two kinds, Green and 
 Bohea. The firft is not only externally green, but likewife imparts the fame 
 colour to Water •> the frefher the Tea, the greener is the infufionj its prevail- 
 ing 
 
Plants and their Parts. 
 
 Tea. ing fmel! is generally that of violets or new hay : Bohea on the other hand is 
 — — ' externally of a blackifh brown colour, gives a brownifh tindbure to Water, and 
 fmells of rofes. Green Tea fhould be chofen frefh, of a fine colour, not in- 
 clining to a yellowifh or brownifh, which are marks of too great age, well 
 rolled, confiding of entire leaves, thoroughly dry fo as to be friable betwixt 
 the fingers, of a bitterifh fubaftringent not ungrateful tafte, and a pleafant 
 light fmell. When either the Violet or Hay-fmell are very ftrong, we may 
 fufpebt them to be introduced by art, the leaves having but little from nature: 
 The firft is communicated by putting into the canifters a little Florence Orris- 
 root ; the latter, by placing the Tea for a few days, wrapt in papers, among 
 new made Hay ; this leaf being remarkably fufceptible of any kind of flavour. 
 There are other abufes common among the Dutch; as mixing, with the Tea, 
 leaves of European growth and manufacftue ; and introducing into the old de- 
 cayed Green, a frefh tindture. 
 
 The preparation and ufe of Tea as a dietetic liquor, are in general well 
 known. With regard to its medical eftedts, fome have excefllvely extolled, 
 and others as extravagantly condemned it. The moil virulent of its antago- 
 nifts is Simon Paulli, who feizes every opportunity of expreffing his diflike to 
 it : His royal Mafter, the King of Denmark, who had found great benefit 
 from Tea, he vehemently difluaded from continuing its ufe, affirming it to be 
 extremely unwholefome ; but all he gained from his Majefty was this equivo- 
 cal anfwer. Credo Te non ejfe fanum. 
 
 Tea is in many cafes a very ufeful liquor; a grateful diluent in health, and 
 a falutary drink in ficknefs: It attenuates vifcid juices, promotes the natural 
 excretions, excites appetite, and proves ferviceable particularly in fevers, in 
 immoderate fleepinefs, after a debauch, and in head-achs arifing from that 
 caufe : No other plant is known, whofe infufion pafies off more freely by the 
 emundtories of the body, or morefpeedily excites the fpirits. It is not however 
 without its inconveniences : In habitual colics it is found to do harm, and in 
 urinary obftrudlions it fhould be fparingly drank : Its immoderate ufe is pro- 
 dudtive of cacochymic, cachedtic, chlorotic diforders, and weakens the tone of 
 the flomach and nervous fyftem. It is faid, when new, to be narcotic, and to 
 diforder the fenles; but to lofe this quality, in great part by the exficcation, 
 and totally by being kept for a year : In the Tea countries, it is a principal 
 caution to abftain from it till this period, but in Europe there is no danger of 
 its being ufed too new. 
 
 Some afcribe the good or ill effedts obferved from the ufe of Tea wholly 
 to the leaves, and others to the Water. The Ample element has undoubtedly 
 a confiderable fhare in both : It is not, as fome have fuppofed, the virtue of 
 the Tea-leaf, but the warm aqueous liquor, with the climate and diet, that 
 preferves the inhabitants of China and Japan from calculous and gouty 
 
 diforders But on the other hand, that the herb communicates alfo fome 
 
 peculiar qualities to the liquor, is equally certain : In weak ftomachs, a 
 moderately ftrong infufion of Tea, without Sugar, generally provokes a puke: 
 An infufion of two or three drams of Bohea in two ounces of Water, is a com- 
 mon emetic among the Chinefe ; and the Green is fometimes employed in the 
 like intention among ourfelves. 
 
 It 
 
Plants and their Parts. 377 
 
 It now remains to examine the phyfico-chemical ftrudture of Tea. Authors Tea. 
 in general make a faline fubftance its prevailing principle : One Hands up for u — 
 a volatile, another for a fixed Salt ; one for an alcaline, another for an acid, 
 and another for an oily Salt; one will have it fmooth, another pointed and 
 rough ; one nitrous, and another fulphureous. But all thefe Salts are crea- 
 tures of imagination, experiment dilcovering nothing of them. The experi- 
 mental analyfis of Tea turned out as follows : 
 
 An ounce of fine Green Tea, digefted with frefii parcels of Water, yielded 
 four drams two fcruples of gummy extract; and afterwards, with Spirit, only- 
 one fcruple of refinous extradt ; three drams remaining undifiolved. On in- 
 verting the order of applying the refpedtive menftrua. an ounce gave four drams 
 and a half of fpirituous, and afterwards four fcruples of watery extradt ; the 
 refiduum weighing three drams ten grains. The green colour refides wholly, 
 and the aftringency chiefly, in the refinous part ; the refinous extradt, made 
 by applying Spirit at firft, being much ftronger and more aftringent, and 
 at the fame time more ungrateful, than the gummy extradt prepared by ap- 
 plying Water at firft. In diftillation, pure Spirit brought over nothing from 
 the Tea: Water elevated all its flavour. 
 
 An ounce of Bohea yielded with Water five drams of gummy, and after- 
 wards with Spirit one fcruple of refinous extradt; two drams and a half of in- 
 diffoluble matter being left : Another ounce, treated firft with Spirit, gave 
 three drams and a fcruple of refinous, and afterwards five fcruples of gummy 
 extradt ; the refiduum amounting to three drams. Though the watery tinc- 
 tures of Bohea are different in colour from thofe of the Green, the fpirituous are 
 nearly of the fame green colour. The diftilled Waters alfo are in flavour 
 much alike, and the diftilled Spirits equally void of flavour. But the firft 
 refinous extradt of Bohea is confiderably lefts ungrateful than that of the other ; 
 and the Refin extradted after Water, more fo. 
 
 A fpirituous extradt made from either kind of Tea, poffefies the whole of 
 its tafte and fmell : But in the watery extradt, prepared in the common man- 
 ner, all the fine flavour of the leaf is loft. Neverthelefs, if the infpiffation of 
 the watery infufion be performed without communication with the air, and in 
 the gentle heat of a water-bath, the extradt will turn out, next to the infufion, 
 one of the moft elegant preparations. Such an extradt, curioufly prepared, 
 may be of ufe to travellers ; the bulk of a pea, diffolved in Water, forming 
 an extemporaneous Tea, without any apparatus. According to fome, the 
 Indians themfelves have a preparation of this kind, for making Tea upon a 
 journey. 
 
 A folution of Vitriol of Iron dropt, in fmall quantity, into an infufion of 
 Tea, changes its colour to a muddy Violet : A larger quantity turns it to an 
 inky blacknels ; a proof that Tea poffefies an aftringent quality. On Handing 
 for fome time, a precipitate falls : It is pretty fingular, that after the precipi- 
 tation, the liquor appears greenifh. Infufions of Tea, like thofe of other ve- 
 getables, are made deeper coloured by alcalies, particularly by thofe of 
 the fixed kind ; and paler by acids, both of the mineral and vegetable 
 kingdom. 
 
 C c c 
 
 COFFEE 
 
Plants and their Parts. 
 
 37 8 
 
 XXVIII. COFFEE Is originally the produce of Arabia, and was not known in 
 C o f f £ e. Europe till the year 1650 : It is now cultivated alfo in Perfia, in the Eaft- 
 v— Indies particularly the illand Java, and in America. It is raifed likewife in 
 botanic gardens in different parts of Europe, but not without (belter and arti- 
 ficial heat : Prince Eugene’s noble garden at Vienna produced Coffee more 
 than fufficient for his own confumption. 
 
 The tree is ufually fmall, though fometimes it rifes to the height of twenty, 
 thirty, and even forty feet : It is an evergreen, and at all feafons of the year 
 is found loaded with flowers and fruit. The flower is highly odoriferous, and 
 re (enables that of the Jafmine, of which the Coffee-tree is held a fpecies : Juf- 
 fieu calls it Jafminum Arabicum lauri folio , cujns femen apud nos Cafe dicitur. 
 The Arabians name the tree Bun or Bon , whence perhaps the common expref- 
 fion of Coffee Beans : The dietetic infuflon prepared from the feeds, they call 
 Cahoueh , or Coave , whence Coffee or Caffee. The entire fruit fomewhat refem- 
 bles a cherry : It contains, under a pulpy fkin, an oval kernel, which lepa- 
 rates longitudinally into two parts, each covered with a thin fhell and marked 
 with a furrow on the flat fide where they were joined. The ripe fruit is tho- 
 roughly dried in the fun, and heavy wooden or ftone rollers palled over it 5, 
 by which the feeds are parted, and the fkins or lhells broken, fo as to be 
 feparated by winnowing. 
 
 Three forts of Coffee are diftinguilbed in trade ; Arabian or Levant, Eafl- 
 Indian or Java, and Weft-Indian or Surinam Coffee; The firfl is the fmalleft, 
 and of a fomewhat darker yellow colour than the other forts ; the fecond is 
 the largeft and of the paleft yellow ; the third, of a middling fize, and in co- 
 lour greenifh. The green colour of this laft may probably proceed from its 
 coming over frefher than the others, or perhaps from its not attaining to fuch 
 a degree of maturity. All the forts are green in their unripe flate ; and even 
 thofe, which by maturity or age have acquired the darkefl: yellow or brownifh 
 colour, give a green tindlure to water. 
 
 Two ounces of thefe feeds yielded with Water five drams, and afterwards 
 with Spirit twenty-fix grains of extradl : On treating the fame quantity firfl 
 with Spirit and then with Water, the fpirituous extradl amounted to three 
 drams and a half, and the watery to two drams : The indiffoluble refiduum 
 weighed in both cafes fomewhat more than ten drams and a half : In diftilla- 
 tion, redtified Spirit brings over nothing, and Water nothing confiderable. 
 The fpirituous extradl is in tafte the flrongefl, and not a little naufeous: The 
 watery is fweetifh and agreeable. 
 
 The peculiar flavour, for which Coffee is admired, is communicated by 
 roafling : Common Beans, Peas and other farinaceous fubflances, receive 
 from that procefs a fimilar flavour, and have been fometimes ufed as fucce- 
 danea to Coffee, and fraudulently mixed, by the venders of that commodity, 
 with fuch as is fold in powder. Dillenius has given an exprefs diflertation (in 
 the Ephem. Nat. Curiofo.) on the fubflances which in fmell and tafle referable 
 Coffee 5 and finds that soaked Rye and roafted Almonds, come the neareft: 
 to it. 
 
 Sixteen 
 
Plants and their Parts. 379 
 
 Sixteen ounces of Coffee were induced by reading to twelve ounces : TheC o ffe eJ 
 exhaling vapour, caught in proper veffels, condenfed into a liquor weighing 
 four ounces, chiefly aqueous, fiightly impregnated with acid, and with a fub- 
 tile Oil of an empyreumatic but agreeable fmell like that of the roafted Coffee 
 itfelf. 
 
 The flavour of the roafted feeds depends on a fimilar oily matter, fo vo- 
 latile as to be diffipated on keeping, but in too fmall quantity to be col- 
 lected in its proper form by diftillation either with Water or Spirit : The dif- 
 tilled Water taftes and fmells confiderably of the Coffee, the diftilled Spirit 
 much lefs. 
 
 Sixteen ounces of roafted Coffee yielded fevea ounces two drams two feru- 
 pies of watery, and afterwards five drams one ferupie of fpirituous extract : 
 
 On inverting the procedure, I obtained from the fame quantity, four ounces 
 four fcruples of fpirituous, and four ounces of watery extract : The refiduum 
 in both cafes was nearly in the fame quantity, namely eight ounces or one half 
 of the Coffee. 
 
 The fpirituous extracts of Coffee are in tafte naufeous : The watery, par- 
 ticularly that made by applying Water at firft, are fufficiently agreeable, 
 fomewhat like that of Walnuts, with a pleafant bitterifhnefs. 
 
 With regard to the medical qualities of Coffee, the common infufions or 
 rather decoctions of it appear to be in general innocent •, to be little difpofed to 
 produce the ill effects aferibed to them by fome ; and to have little claim to 
 the extraordinary virtues for which they are recommended by others. Simon 
 Paulli was the firft who condemned the ufe of Coffee as well as Tea : But his 
 prejudices againft it are built on no better foundation than a ridiculous hiftory 
 related in Olearius’s travels. 
 
 
 VERONICA or Male Speedwell ( Veronica mas fupina C? vulgatiffima 
 C. B.) a fmall plant common in uncultivated places, is greatly recommended Veronica 4 
 by Hoffmann and Joh. Francus as a fubftitute to Tea, and faid to be of ex- v_ 
 cellent fervice in diforders of the bread and many other difeafes. 
 
 The leaves of Veronica have a bitterifli fomewhat aftringent tafte, with a 
 very weak fmell. An ounce of the leaves, picked and dried, yielded with 
 Water five drams and a fcruple, and afterwards with Spirit only nine grains of 
 extract, the refiduum weighing two drams thirty-five grains : On inverting 
 the order of applying the menftrua, I obtained, from an ounce, three drams 
 two fcruples of fpirituous, and a dram and a half of watery extract, the in- 
 diifoluble refiduum amounting to two drams forty-fix grains. 
 
 The extract made by Spirit at firft contains the green colour, and all the 
 a drive matter of the herb ; rectified Spirit extracting the whole of its tafte and 
 fmell, and elevating nothing in its exhalation. The watery extract is weaker 
 than the fpirituous : The diftilled Water fmells and taftes a little, and but a 
 little, of the Veronica : If the herb be previoufly fermented, we obtain by 
 diftillation a liquor ftrongly impregnated with its flavour. 
 
 Hoffmann reports, that Veronica, burnt to afhes, yields a larger quantity 
 of fixed alcaline Salt than any other plant except Wormwood. 1 made the 
 
 C c c 2 experi- 
 
380 Plants and their Parts. 
 
 Veronica, experiment three different ways. Sixteen ounces of the leaves, diftilled In 3 
 retort, left five ounces of a black coal, which by gentle burning in the open 
 air, was reduced to one ounce of afhes : From this were obtained, by elixa- 
 tion with Water and infpiffation, two drams and two fcruples of Salt. An- 
 other pound of the leaves being burnt flowly with a fmothering heat, the 
 afhes weighed an ounce and a half, and the Salt two drams thirty-five grains, 
 of which one dram and a half affumed a cryftalline form. A third pound, 
 burnt with a flaming fire, gave ten drams and a half of afhes, from which 
 were obtained one dram of cryftallifed and four fcruples of infpiffated Salt. 
 This plant therefore does not afford near fo much Salt as has been reported, 
 nor is the Salt purely alcaline, great, if not the greatefl, part of it being, as 
 Stahl has juftly obferved, marine Salt. The afhes, in the two firfi; experi- 
 ments, were ponderous, and of a yellowifh white colour ; in the laft, they 
 were light, fpongy, and of a bluiffi white. 
 
 XXX. LUNGWORT, Pulmonaria , is a fpecies of Mofs ( Mufcus pulmonarius C. B.) 
 Lungwort, growing upon trees, of a very irregular figure, concave and greenifh on the 
 1 - fide next the tree, convex and yellowifh on the upper fide, full of holes, thin, 
 
 membranous, like leather or paper, internally of a whitifh colour. It has 
 been held a fpecific in diforders of the bread and lungs, as alfo in dyfenteries, 
 vomiting, &c. though the virtues afcribed to it do not appear to have any 
 good foundation. 
 
 An ounce, digeffed in fre fin parcels of re&ified Spirit, gave five drams 
 wanting half a fcruple of refinous extract ; and afterwards with Water only 
 twelve grains of a gummy one : Another ounce, treated firfi: with Water and 
 then with Spirit, yielded three drams of gummy and two fcruples of refinous. 
 extract : So that a confiderably larger quantity of the two extra&s is gained 
 when Spirit than when Water is applied firfi. 
 
 I obferved alfo, that the green colour refides in the refinous parts ; that the 
 fpirituous extradl is difficultly reduced to a due confidence ; that the firfi fpiri- 
 tuous extradl is very apt to grow mouldy, contracting in a ffiort time not only 
 white hairy efflorefcences, but likewife a yellow powdery matter; that the firfi 
 extracts, whether made with Water, or with Spirit, retain in part the ill 
 fmell perceivable in the Lungwort itfelf ; that in diftillation. Spirit of Wine 
 arifes unchanged ; and that the diftilled Water has only a kind of ungrateful 
 muftinefs. 
 
 XXXI PAR El R A BRAVA, Bulua , Cipo de cobra , is the root of a velvet- 
 Pareira ^ eave d climbing plant, growing in the Brazils, called by Ray Convolvulus Bra - 
 Brava zilianus^ jlore o£lopetalo, monococcus. The root is pretty large, irregular, of a 
 1 h woody texture, compofed of longitudinal fibres, which partly feparate in dry- 
 
 ing, fo as to leave manifeft vacuities. 
 
 Mr. Geoffroy, in a ffiort Memoir in the year 1710, makes two forts of this 
 root ; one of a whitifh colour on the outfide and a Citron yellow within, the 
 other brown without and brownifh yellow within. I have been affured, that 
 both are the roots of the fame plant ; that the young roots are externally 
 fomewhat whitifh, and internally of a light Citron yellow 5 and that by age 
 
 5 they 
 
Plants and their Parts* 381 
 
 they become paler within, and of a dark fometimes blackifh brown colour Pareira 
 without. Brava. 
 
 This root is faid by Pomet to have been firft introduced into France in the 
 year 1688, by M. Amelot then embaffador in Portugal. Helvetius brought, it 
 into great efteem as a medicine, for diffolving and promoting the expulfion 
 of thick vifcid juices, in nephritic, ideric, hydropic and other diforders. It 
 has no fmell unlefs warmed, in which circumftance it fmells fomewhat like 
 liquorice : To the tafte, it difcovers as it were a fweetnefs and bitternefs 
 
 blended together. 
 
 An ounce, cut in fmali pieces, and digefted in frefh parcels of rectified 
 Spirit of Wine fo long as it continued to give any tinge to the menftruum, 
 yielded, on infpiffating the tindures, two drams three grains of refinous ex- 
 trad , after which, Water extracted one dram,, leaving five drams undifiolved. 
 
 On inverting the order of applying the refpedive menftrua, the fame quantity 
 of the root yielded two drams one fcruple of watery, and afterwards one dram 
 fix grains of fpirituous extract : The indifibluble refiduum weighed in this cafe 
 but four drams and a half. The firft fpirituous extrad is in talte the ftrongeft 
 of all the preparations : The firft watery extrad alfo contains nearly the whole 
 of the adive matter of the root, though it does not prove near fo ftrong as the 
 fpirituous : The extrads made by Spirit after Water, or by Water after 
 Spirit, have very little tafte. Nothing arifes in diftillation either with Spirit 
 or with Water. 
 
 CHINA, Cina, or Schina-root is of two kinds, Oriental and Occi- XXXII. 
 dental. The two plants differ little or nothing in the leaves, flowers, or feeds, China- 
 but confiderably in the root, and remarkably in the time of flowering ; the root. 
 Chinefe blowing only in June and July, whilft the American produces flowers 
 fucceflively almoft all the year. By fome botanifts they are referred to the 
 genus of Smilax ajpera , by others to that of Senecio : The flower is compofed of 
 a number of flofculi, of a gold yellow colour the leaves narrow and indented, 
 like thofe of Dandelion. 
 
 The root, when frefh, is flefliy and full of juice ", as brought to us, hard 
 and woody : It is very irregular, and full of knots. The Oriental fort, which is 
 accounted the belt, is commonly fhorter, thicker, lefs crooked and lefs knotty 
 than the American : It is alfo of a much paler reddifh white colour on the in- 
 ftde, the American being of a pretty deep reddifh, nearly like that of Biftort :• 
 
 The outfide is of a reddifh brown, a lull brown, or a blackifh. The greateft 
 quantities are brought over by the Dutch Eaft-India company, in bags of one 
 hundred and twenty-five pounds : The merchants in Batavia give the Chinefe, 
 for luch a bag, commonly four florins, fometimes more, at the higheft ten. 
 
 As this root is very fubjed to be preyed upon by worms, the induftiious 
 Dutch have contrived means for palliating that imperfedion. 1 was once in a 
 houfe at Amfterdam, where the manufadure of Afafetida, Caranna^, Caftor,, 
 
 Mufk, and fundry other drugs, was carried on. Among other ingenious ope- 
 rators, there were fix perfons fitting by a difh, making old worm-eaten China- 
 roots as fair and frefh coloured as any that ever came from China. They had 
 a mafs compofed of powdered China-root, Bole Armenic, andGumTraga- 
 
 canthy 
 
382 Plants and their Parts.. 
 
 C h 1 n a* canth, with probably fome admixture of Litharge, for it was very heavy: 
 Root. This looked, when dry, exactly of the reddifh-white colour of the internal part 
 v— — ^ of the root. With this mixture they curioufly filled all the holes they could 
 come at, then penciled the root all over with fome of the fame mafs diluted, 
 afterwards with another tindure, and lafily rubbed it with Sope. 
 
 The befb China-root is moderately compad and heavy ; when broke, not 
 mealy or dufty, but clofe and of an oily or refinous appearance. It has no 
 fmell, and fcarcely any tafte, or only a flight kind of aftringency. Two 
 ounces yielded five fcruples of fpirituous extrad, and afterwards four drams 
 fourteen grains of watery extrad : On inverting the order of applying the men- 
 ftrua, I obtained from the fame quantity, five drams ten grains of watery, 
 and afterwards only fourteen grains of fpirituous extrad:. 
 
 Decodiions of this root drank freely, are faid to promote perfpiration and 
 urine, and have been greatly commended in the venereal difeafe : They do not 
 appear, however, to have any confiderable virtue. If this root poffefies any 
 medicinal adivity, the fpirituous extrad promifes from its tafte, to be the belt 
 preparation, 
 
 XXXIII. SARSAPARILLA, Salfaparilla, Zarza, the root of another Ame~ 
 Sarsapa- rican Smilax, confifts of a number of long, frnooth, flexible firings hanging 
 rill a. from one head, eafily fplit from end to end. There are different fpecies of 
 v— > this plant, and the roots of feveralof them are met with in the fliops. Mo- 
 nardus diftinguifhes three : One, brought from N«w Spain, of a whiter colour 
 and flenderer than the reft j another, from the province Honduras, of a darker 
 afti-grey colour, thicker, and better than the foregoing ; and the third, from 
 the neighbourhood of Guayaqui in the province of Quito (hence called Sarfa- 
 ■ parilla Guajaquillana ) of a darker colour than either of the others, inclining to 
 black, thicker, longer, fometimes of the length of a man. Three forts are at 
 prefent alfo diftinguifhed in the fhops ; one which comes over in circular 
 coils, another infhort, and the third in long bundles : The firft is called Vir- 
 ginian or Englifh, the fecond Spanifh, and the third Lifbon Sarfaparilla. The 
 firft is univerfally preferred, the others being fubjed to have decayed roots and 
 different foreign matters in the middle of the bundle. It is rare to meet with 
 Sarfaparilla that is truly good. The beft is externally of a light brown colour, 
 not greyifh, or dark brown, much lefs of a blackifh hue : Internally it is white, 
 and in appearance as it were farinaceous, with a compad pith in the middle, 
 not porous or fpongy, much lefs powdery or dufty. It has no fmell, and 
 hardly any tafte, or only a juft perceptible bitterifh and fomewhat mucilagin- 
 ous one. 
 
 From fixteen drams of the choiceft roots were obtained fix drams of watery, 
 and afterwards only half a fcruple of fpirituous extrad : Spirit applied at firft 
 to the fame quantity of the root, extraded four drams, after which water took 
 up two*, the indiffoluble earthy refiduum weighed in the firft cafe nine drams 
 fifty grains, in the latter ten drams. Both the extrads made at firft were bit- 
 terifli, with this difference, that the fpirituous was the moft difagreeable, and 
 the watery fomewhat laline : The fecond extrads, or thofe made by water after 
 
Plants and their Parts. 383 
 
 fpirit, and by fpirit after water, had fcarcely any tafte. Neither water or fpiritSARSAPA- 
 brought over any thing confiderable in diftiilation. rilla. 
 
 This root is laid to be remarkably ferviceable in venereal and cancerous dif- e. — 
 orders, and in impurities and vifcidities of the blood and juices in general. 
 
 Some nave given it in the form of powder, but it is more generally and more 
 advantageouOy directed in decoCtions. The watery decoCtion and extract 
 feem to be the belt preparations, though the fpirituous alfo are not to be re- 
 jected- The colour of the tinClures is nearly the fame with thofe of Sope- 
 
 wort; the fpirituous being of a yellowifh red, and the watery of a reddifh- 
 brown. 
 
 S O P E W O RT, Saponaria {Saponaria major l avis, C. B.) fo called from the XXXIV. 
 frefh leaves of the plant cleaning the hands like Sope, grows wild in woods Sopewort. 
 and meadows, butiseafily propagated in gardens : It loves a moift and fome- ^ 
 
 what fandy foil : It rambles furprizingly with its roots, fpreading in a little 
 
 time to a vaft compafs, fo as not to be eaflly extirpated. 
 
 The root is long and flender, with knots and fibres here and there, covered 
 with a reddifh- brown bark, under which lies a white tough fubftance, and in 
 the middle a yellowifh pith. This root has ip manifeft fmell : Its tafte is 
 fweetilli, accompanied with a light pungency. It has lately come into efteem 
 as a relolvent and purifier of the blood, of great fervice in venereal and lcro- 
 phulous diforders, fimilar, but fuperior to Sarfaparilla : Stahl was extremely 
 fond of it. ✓ 
 
 On a chemical analyfis, by water and rectified fpirit, two ounces of the root 
 yielded eleven drams of watery, and only half a fcruple of fpirituous extraCl, 
 the refiduum weighing four drams two fcruples and a half : Two other ounces, 
 treated firfl: with fpirit and then with water, gave five drams of fpirituous, and 
 fix drams of watery extraCl, the refiduum amounting to five drams. All the 
 aCtive parts are taken up by the menftruum applied at firfl, whether watery or 
 fpirituous ; the extracts made by water after fpirit, or by fpirit after water, 
 having fcarcely any perceptible tafte. 
 
 Both the firfl: extracts, on being chewed a little, cover the mouth and fauces 
 with a pleafant, foft, fmooth, flippery fubftance, like frothy Saliva, accom- 
 panied with a flight warmth and pungency : The fpirituous is fweeter and 
 ftronger than the watery : The colour alfo of the fpirituous tinCture is a deeper 
 reddifh than that of the watery decoCtion. In diftiilation, fpirit elevates no- 
 thing, and the diftilled water has only a juftfenfible kind of l'weetifhnefs. 
 
 N 
 
 THE roots of common Burdock ( Bard ana, perforata, lappa major) are XXXV. 
 nearly fimilar in quality to the foregoing: They have a flight fweetilh tafteBuRDOcK, 
 
 without any fmell, and are fuppofed to pofiefs the fame medicinal virtues, i v — 
 
 This root is pretty long, an inch or more in thicknefs, externally of a yellow, 
 a brownifh, and fomefimes of a dark brown colour, internally for the moft 
 part fomewhat hollow, moderately compaCt and of a blackifh-grey colour to- 
 wards the furface, lined here and there with a white foft matter, and furnifhed 
 with a white fpongy pith in the middle. 
 
 Sixteen 
 
3 8 4 
 
 Plants and thsir Part s. 
 
 Burdock. Sixteen drams of the dry root yielded with water feven drams fifty-two 
 grains of ex trad, and afterwards with rectified fpirit two fcruples and a half-, 
 from the fame quantity, treated firfi: with fpirit, I obtained five drams ten 
 grains, after which water extraded three drams two fcruples two grains : When 
 fpirit was ufed firft, the indifloluble refiduum weighed feven drams fourteen 
 grains ; when water, feven drams twenty-two grains. Water appears to be 
 the beft menffruum, and the diftilled liquor to be of no value. 
 
 It is affirmed in the Epbemerides natura curio forum , that the leaves of this 
 plant deflagrate in the fire like Nitre ; and hence it is concluded, that Nitre, or 
 a nitrous Salt, is one of its efiential ingredients. We have formerly obferved, 
 that plants imbibe Nitre from nitrous foils : The Nitre in this experiment, was 
 no other than that cafual impregnation. I have burnt the leaves of Burdock, 
 and ftrewedupon burning coals an efiential Salt extraded from them, without 
 obfervingthe leaft deflagration or mark of Nitre. 
 
 XXXVI. TURMERIC, Curcuma , Terra merit is the root of an oriental plant. 
 Turmeric, called by Tournefort Cannacorus radice crocea , growing in Cananor, Calecut, 
 t*-— -v ~— - > Goa, Malabar, &c. There are two forts of this root, a long and a round : 
 The firfi; is the bell, and hence is the only one commonly made ufe of. It 
 fliould be chofen large, frefh, compad, ponderous, not eafy to break, of a 
 fine yellow colour on the outfide, and a deep reddifh-yellow within : It has a 
 bitterifh tafte, and fmells fomewhat like Ginger. 
 
 This root is ufed by the Indians as a fpice : Medicinally, it has been fome- 
 times given as a relblvent in cachedic, ideric, hypochondriacal, hyfterical and 
 other diforders -, but its principal ufe is as a colouring drug, for dying cloth 
 and draining leather yellow, and in yellow varnifhes. It is obfervable, that 
 fixed and volatile alcalies heighten its colour into a red, whilft: the nitrous and 
 vitriolic acids weaken and incline it to a blackifh- brown : If the root, how- 
 ever, be afterwards dried, its colour appears not to be greatly different from 
 what it was at firfi:. 
 
 It gives out its colour both to watery and fpirituous menftrua (z). Sixteen 
 drams yielded with water five drams and one fcruple of extrad, and afterwards 
 
 with 
 
 (/) Turmeric— colour to water and fpirit. ] It 
 communicates to water its own deep yellow 
 colour, but to redified Spirit of Wine a 
 red. The fpirituous tindure, applied upon 
 warm Marble, gives a durable red ftain. 
 Woollen-cloth, impregnated with a folution 
 of Alum and Tartar, acquires on being 
 boiled with the watery decodion, an ele- 
 gant, but not very durable Orange yellow 
 or Gold coloured dye. It is rarely made 
 ufe of by the dyers on account of its price 
 and the perifhablenefs of its colour. 
 
 There are feveral other colouring drugs 
 which belong- to this clafs : The principal 
 areFuftick, Nephritic-wood, Log-wood, 
 Brazil wood, and Madder. 
 
 F U S T I C K. 
 
 TC'USTICK is the wood of a fpecies of 
 -*• Mulberry-tree, growing in Jamaica and 
 Brazil, called by Sir Hans Sloane Morus 
 fruftu viridi, ligno fulphureo tindiorio. It is 
 of a deep Sulphur yellow colour, whkrh it 
 readily gives out both to water and to fpirit. 
 The watery decodion dyes prepared woollen 
 of a very durable Orange yellow : The co- 
 lour is imbibed by the cloth in a moderate 
 warmth without boiling. 
 
 The Fujlet or Fujlel of the French is a 
 yellow wood or root very different from 
 ourFuftick: It gives a fine Orange dye 
 to woollen, but the colour is extremely 
 
 perifhable 
 
Plants ci7id their Parts. 
 
 perilhable in the air. The plant grows 
 wild in Italy and Provence, and is culti- 
 vated with us in gardens on account of the 
 beauty of its flowers : It is called Venice fu - 
 mad?, Cotinus coriaria or Coccigria ; Cotinus 
 ?natthioli , C. B. 
 
 NEPHRITI C-W O O D. 
 
 T HIS wood is brought from the Eaftern 
 countries in large pieces, covered with 
 a dark blackifh bark. The wood is hard, 
 heavy, compact, of a fine grain, of a whitifh 
 or pale yellow colour on the outfide, and a 
 duflcy reddifh-brown in the heart. Of the 
 tree we have no very certain account. 
 
 This wood, particularly the outer pale 
 part, gives out both to water and to redlified 
 Ipirit, a deep tinfture, appearing when placed 
 betwixt the eye and the light, of a golden 
 colour, in other fituations blue. Hence it is 
 named by Cafpar Bauhine Lignum peregri- 
 num aquam caruleam reddens. By this mark 
 it is eafily diftinguilhed from pieces of a 
 different kind of wood, which are fome- 
 times mixed with it, and which give only 
 a yellow tindture to water. 
 
 It is remarkable, that the blue colour of 
 the infufion of Nephritic-wood is deftroyed 
 by acids, the liquor after the admixture of 
 thefe, appearing in all fituations yellow; and 
 that the addition of alcalies, either of the 
 fixed or volatile kind, in quantity fufficient 
 to neutralize the acid, reftoresthe bluenefs. 
 No other woody matter is known that gives 
 any degree of blue tinfture ; and no other 
 vegetable blue is known, that is thus de- 
 itrudlible by acids. 
 
 This wood is at prefent rarely met with 
 in the {hops. Nor is it applied to any ufe, 
 except that fome have employed it medici- 
 nally, and expedted from it diuretic virtues, 
 whence its name Nephritic-wood . 
 
 LOGWOOD. 
 
 T OGWOOD or Cam peachy wood 
 T' ( Lignum hrazilio fimile , caruleo tingens J. 
 B .) is the wood of a low prickly tree, which 
 grows plentifully about Campeachy on the 
 Bay of Honduras, and has of late been in- 
 troduced into fome of the warmer of the 
 Britifh plantations, particularly Jamaica: 
 It is a native of low marfhy places. The 
 wood comes over in pretty large logs, 
 
 cleared from the bark : It is very hard, com- 
 pact, heavy, and of a red colour. 
 
 Logwood gives out its colour both to wa- 
 tery and fpirituous menftrua, but not readily 
 to either: It requires to be rafped and 
 ground into fine powder, and boiled in fe- 
 veral frelh parcels of the liquors. Rectified 
 fpirit extradls the colour more eafily, and 
 from a larger proportion of the wood than 
 water does. 
 
 The tinctures both in water and in fpirit 
 are of a fine red, with an admixture, par- 
 ticularly in the watery one, of a violet or 
 purple. Volatile alcaline Salts or Spirits 
 incline the colour more to purple : The ve- 
 getable and nitrous acids render it pale ; the 
 vitriolic and marine acids deepen it. 
 
 The watery decodtion, wrote with on pa- 
 per, lofes its rednefs in a few days, and be- 
 comes wholly violet. This colour it com- 
 municates alfo to woollen-cloth previoufly 
 prepared by boiling with a folution of 
 Alum and Tartar: The dye is beautiful,, 
 but very perifhable. It is often ufed by the 
 dyers, as an ingredient in compound co- 
 lours, for procuring certain fhades which 
 are not eafily hit by other materials. 
 
 With Chalybeate folutions, it ftrikes a 
 black. Hence it is employed in conjundtion 
 with thofe liquors, for ftaining wood black 
 for pidture-frames, &c. and with the addi- 
 tion of Galls, for dying cloth and hats blacks 
 The black dyes, in which this wood is an 
 ingredient, have a particular luftre and foft- 
 nel's, far beyond thofe made with Galls and 
 Vitriol alone : The beauty, however, which 
 it here imparts, is not permanent, any more 
 than its own natural violet dye. 
 
 On the fame principle, it improves alfo 
 the luftre and blacknefs of writing ink. 
 Ink made with Vitriol and Galls, does not 
 attain to its full blacknefs till after it has 
 lain fome time upon the paper : A due ad- 
 dition of Logwood renders it of a deep 
 black as it flows from the pen, efpecially 
 when Vinegar or white Wine is ufed for 
 the menrtruum. 
 
 Decodlions and extradls made from Log- 
 wood have an agreeable l'weetilh tafte, fol- 
 lowed by a flight aftringency. They have 
 lately been introduced into medicine, and 
 given with fuccefs in cafes where mild re- 
 ftringents are required. They often tinge the 
 ftools, and fometimcs the urine of a red co= 
 lour, 
 d d 
 
 38s 
 
 Woods. 
 
 BRAZIL, 
 
3 86 
 
 Plants and their Parts. 
 
 Woods. 
 
 BRAZIL. 
 
 f>RAZIL is a red wood, brought from 
 the province of that name in South- 
 America. There are different forts of it, 
 diftinguifhed by the names of Fernambouc, 
 St. Martha, &c. What differences there 
 are in the trees we know not : The woods, 
 brought to us, differ little otherwife than as 
 different parts of one log, fome pieces being 
 richer in colour than others. 
 
 This wood is called by Cafpar Bauhine 
 baflard Red-faunders, Pfeudof ant alum ruhrian 
 five arbor Brasilia. Many have confounded 
 fl with the true Red-faunders : The college 
 of Brulfels, in their account of that wood, 
 have plainly miftaken the Brazil for it. 
 However the two trees may be allied in their 
 botanic characters, the woods, chemically 
 confidered, are very obvioully different; 
 Brazil wood readily giving out its red co- 
 lour to water, whilft Saunders gives no red 
 tinge to any aqueous liquor. The watery 
 tinCture of Brazil however, is not quite fo 
 deep as that made in rectified Spirit of 
 Wine, or in volatile alcaline fpirits. 
 
 The fpirituous tinCture Rains warm 
 Marble of a purplifh red, which upon in- 
 creafing the heat, becomes violet. Mr. du 
 Fay informs us, in a paper upon this fub- 
 jeCt in the French Memoirs, that if the 
 Rained Marble be covered v/ithWax and 
 confiderably heated, it changes through all 
 the fhades of brown, and fixes at lafl in a 
 Chocolate colour. 
 
 The colour of the watery decoCtion is 
 heightened by Alum, and inclined to a crim- 
 fon. A decoCtion made with Alum, in the 
 proportion of about one part of the Salt to 
 four of the wood, yields upon adding alca- 
 line Ley or volatile fpirits, a kind of crim- 
 fon lake verging a little to violet. 
 
 Solution of Tin in Aqua fortis, added to 
 the decoCtion, throws down a much finer 
 coloured Precipitate, little inferior in beauty 
 to Carmine. This experiment, firfl com- 
 municated in the Asia natures curioforum , I 
 have feveral times repeated with fuccefs. 
 The quantity of lake is largeft when Alum 
 is ufed in making the decoCtion ; but the 
 colour is much the fineft without it. 
 
 A tranfparent crirnfon for water-colours is 
 (aid to be made by boiling the wood in 
 
 fmall Wort with a little Tartar. A large 
 proportion of Tartar weakens the colour. 
 All acids, if their quantity is confiderable, 
 have this effeCt : Thofe of the mineral king- 
 dom totally deltroy it. 
 
 Brazil wood dyes woollen of a red colour, 
 which does not want beauty, but has little 
 durability. Mr. Hellot gives a pretty remark- 
 ably procefs, by which both the beauty and 
 permanency of the dye are improved. He 
 direCls the wood, cut in fmall pieces, to be 
 boiled in two frefh parcels of the hardefl 
 well-water that can be procured ; the de- 
 coCfions to be mixed together, and kept in 
 a cafk, till they ferment, grow Rale, and ap- 
 pear ropy like an unCtuous Wine, The 
 cloth is to be boiled for three hours with 
 Alum and Tartar, in the proportion of fix 
 or eight ounces of the former, and two or 
 lefs of the latter, to every pound, and after- 
 wards kept moiR, in a cool place, for eight 
 or ten days, that it may be thoroughly pe- 
 netrated by the Salts. A quantity of the 
 Rale decoCtion of Brazil is made to boil in 
 a copper, and fome common coarfe Ruff, 
 prepared as ufual with Alum and Tartar, 
 dyed in it : Half as much more of the liquor 
 is then added, and another piece of cloth 
 dyed ; fo as that, between the two, about 
 three fourths of the colour may be taken up. 
 The cloth prepared as above is now to be 
 dipt, and the liquor kept gently boiling, til! 
 it has taken the colour uniformly. The 
 red, obtained by this procefs, is a lively 
 and durable demifcarlet : On expofure to 
 the air for four months, in winter, it loR 
 nothing, but on the contrary became deeper, 
 and feemed to gain a body. 
 
 The fame author gives another method 
 of fixing the colour of Brazil by afiringents : 
 The dyes thus produced are not red, but 
 coflees and purple-chefnuts very beautiful 
 and gloffy. For this purpofe, he dilutes 
 the Rale decoCtion of Brazil with twice its 
 quantity of water ; and adds, for every 
 pound of cloth, about an ounce of powdered 
 Galls, and half an ounce of Gum Arabic, 
 The cloth, prepared with Alum and Tar- 
 tar, and kept moiR for fifteen days, is boiled 
 in this liquor for an hour or two, according 
 as the colour is wanted lighter or deeper, 
 and fuffered to grow thoroughly cold before 
 it is wafhed. 
 
 MAD- 
 
Plants and their Part s. 
 
 3 8 7 
 
 MADDER. 
 
 ADDER ( Rubin tinttarnm fatlva C. 
 
 B .) is one of the afperifolious ftellated 
 plants, or of thofe which have rough nar- 
 row leaves fet in form of a ftar at the joints 
 of the ftalks. The root, which is the only 
 part made ufe of, is long, flender, of a red 
 colour both on the outfide and within, ex- 
 cepting a whitifh pith which runs along the 
 middle. 
 
 This plant was formerly cultivated a- 
 mong us in quantity for the ufe of the 
 dyers, who for fome time paft have been 
 fupplied from Holland and Zealand : Its 
 culture is now again fet on foot in this 
 kingdom, under the laudable encourage- 
 ment of a publick fociety. We have for- 
 merly obferved, that the colour of fome exo- 
 tic plants, as Alkanet, degenerates in our 
 climate ; but this is not the cafe with Mad- 
 der, the Englifh Madder being equal to the 
 bell that is brought from abroad. 
 
 Madder-root gives out its colour both to 
 water and to rectified fpirit : The watery 
 tindlure is of a dark dull red, the fpirituous of 
 a deep bright one. Taken internally (for it 
 has fometimes been ufed medicinally as an 
 aperient and diuretic) it tinges the urine 
 red. In the Philofophical Tranfa&ions, 
 and in the Memoirs of the French Academy, 
 there are accounts of its producing a like 
 effetft upon the bones of animals, to whom 
 it had been given with their food : All the 
 bones, particularly the more folid ones, 
 were changed both externally and internally 
 to a deep red, but neither the cartilaginous 
 or flefhy parts fuffered any alteration. Some 
 of thefe bones, macerated in water for many 
 weeks together, and afterwards fteeped and 
 boiled inSpirit of Wine, loft nothing of 
 their colour, nor communicated any tinge 
 to the liquors. 
 
 The dealers in this commodity make 
 three forts of it ; Madder in the branch. 
 Madder in the bunch or in the bundle, and 
 Madder unbundled. Madder in thebranch is 
 the entire root dried : This, ground in mills 
 into a grofs powder, is the unbundled Mad- 
 der : The bundled or bunch Madder is a 
 powder of the finer roots, freed from the 
 outer bark and from the pith. It is laid 
 that by keeping for two or three years, in 
 clofe calks, the colour is improved ; in open 
 veffels it decays. 
 
 Madder imparts to woollen-cloth, pre- Madder. 
 pared with Alum and Tartar, a very dur- (w-v— 
 able, though not a very beautiful red dye. 
 
 As it is the cheapeft of all the red drugs 
 that give a durable colour, it is the principal 
 one commonly made ufe of for ordinary 
 fluffs. Sometimes its dye is heightened by 
 the addition of Brazil-wood ; and fome- 
 times it is employed in conjunction with the 
 dearer reds, as Cochineal, for demifcarlets 
 and demicrimfons. Mr. Hellot (from whofe 
 Art de teindre the remaining part of this note 
 is extracted) informs us, that thofe who 
 dye the beft Madder reds are particularly 
 careful to keep the liquor of a heat confi- 
 derably belowboiling, increafing the fire only 
 towards the end, fo as to make it boil for 
 a minute or two juft before the cloth is taken 
 out, to confirm the dye. A boiling heat en- 
 ables water to extraft not only the red but a 
 tawny or brownilh matter, which debafes 
 the red to a dull brick colour. 
 
 The proportion of Madder is, about half 
 the weight of the cloth. The beft propor- 
 tion of Salts for preparing the cloth to re- 
 ceive the dye, feems to be, five parts of 
 Alum, and one of red Tartar, for fixteen 
 of the fluff ; which is to be boiled with 
 thefe for two hours or longer, then kept 
 moift for fome days, and afterwards digefted 
 with the Madder. 
 
 A variation in the proportion of the Salts 
 varies the colour communicated by the 
 Madder ; and not only the fhade but the 
 fpecies of colour. If the Alum be dimi- 
 nifhed and the Tartar increafed, the dye 
 proves a red Cinnamon : If the Alum be 
 entirely omitted, the red is deftroyed, and a 
 very durable tawny Cinnamon is produced. 
 
 On boiling the dyed cloth in weak alca- 
 line Ley, great part of the colour is de- 
 ftroyed, and the remainder appears of a 
 dirty or a kind of fallow hue: Solution of 
 Sope, on the other hand, difcharges a part, 
 and leaves the remaining red more lively 
 than before. 
 
 Volatile alcalies heighten the red colour 
 of Madder, but at the fame time render it 
 fugitive like themfelves : Madder prepared 
 with Lime and Urine, after the manner 
 pradtifed for Archil, loft its red colour on 
 attempting to dye with it, and communi- 
 cated to the cloth only permanent nut co- 
 lours. 
 
 If a pure red, as that of Cochineal, be 
 
 applied 
 
 D d d 1 
 
388 Plants and their Parts. 
 
 Turmeric, with fpirit only two fcruples and a half, ten drams remaining undlflolved. 
 
 The fame quantity, treated firft with fpirit, gave two drams and a half, and 
 afterwards with water three drams and a half, ten drams of earthy matter re- 
 maining as before. In diftillation, pure fpirit brings over nothing: The di- 
 ftilled water fmells of the Turmeric, and difcovers fome little drops of efien- 
 tial Oil. 
 
 CLASS IV. 
 
 UNCTUOUS VEGETABLES. 
 
 unctuovs Y TNDER this divifion are included thofe vegetables which abound with a 
 Vegetables; grofs, inodorous, infipid Oil, feparabie by exprefiion •, as Almonds, the 
 kernels of moft fruits, and many kinds of feeds. An Oil of the fame kind ap- 
 pears to be contained in all vegetable matters, though it cannot be feparated 
 from all in its proper form : All vegetables yield an empyreumatic Oil on be- 
 ing diftilled by a ftrong fire ; and this fee ms to be no other than the native 
 Oil of the fubjedt, rendered fubtile, acrid and empyreumatic by the heat. 
 
 Almonds. TH E R E are two kinds of Almonds, fweet and bitter ; and fome varie- 
 i _ . ties of each of thefe, proceeding from the foil and climate. The tree which 
 
 bears the common fweet Almonds is called by Tournefort and Cafpar Bauhine 
 Amygdalns fativa ; and that which produces the bitter, Amygdalus amara. They 
 both refemble the Peach-tree in the leaves and flowers, but grow to a much 
 larger fize : It is obferved, that they do not well bear being tranfplanted. 
 The greateft quantities of Almonds are produced in Syria, Barbary, Turkey, 
 Spain, Italy, the ifland Cyprus, and France. The German fhops are fupplied 
 
 chiefly 
 
 applied on cloth which has been previoufly 
 dyed blue, and afterwards prepared for re- 
 ceiving this red by boiling with Alum and 
 Tartar, a purple or violet will be produced, 
 according as the blue or the red prevail. 
 The .Madder red has not this effeA ; for as 
 its colour is not a pure red, but is tarnilhed 
 by the tawny matter which its woody fibres 
 have in common with other roots ; it gives 
 upon blue only a chefnut dye, more or lefs 
 deep according to the deepnefs of the blue 
 applied firft. 
 
 There are, however, means of obtaining 
 from Madder a fine purple, without the ad- 
 dition of any other colouring drug. A piece 
 ©f white woollen-cloth, weighing half an 
 ounce, was boiled for half an hour with ten 
 grains of Roman Alum, and fix grains of 
 cryftals of Tartar, and then taken out, 
 fqueezed, and fuffered to cool. Twenty- 
 four grains of bunch Madder were added to 
 -the fame liquor j and after the Madder had 
 
 given out its colour, twenty drops of a folu- 
 tion of Bifmuth (made in Spirit of Nitre di- 
 luted with equal its weight of water) were 
 dropt in. The cloth was now dipt again, 
 and in half an hour taken out, fqueezed, 
 and wafhed : It appeared of a crimfon co- 
 lour, nearly as beautiful as if it had been 
 dyed with Cochineal. To fry the effedf of 
 loading it further with the colouring mat- 
 ter, it was returned into the liquor and 
 boiled for a quarter of an hour longer : It 
 had now acquired a purple colour fuffici- 
 ently vivid. 
 
 On varying this experiment, by keeping 
 the cloth moift for fome days after the pre- 
 paration with Alum and Tartar, then dip- 
 ping it in a plain decodtion of Madder made 
 as ufual without Salts ; and adding, when 
 it had gained a bright Cinnamon colour, the 
 fame folution of Bifmuth, the dye, inftead 
 of a purple, proved only a chefnut. 
 
Plants and their Parts, 389 
 
 chiefly From Provence and Valencia. In England, three forts of Almonds are Almonds. 
 diftinguifhed, fmall Barbary Almonds, long Jordan Almonds, and fhort, v— —y—J 
 broad, Spanifh or Valencia Almonds. 
 
 Sweet Almonds confift chiefly ofexpreflible Oil and a fine farinaceous earth : Sweet. 
 
 The Oil is fo plentiful, and fo loofely intermixed with the other principles, that 
 a part of it may be fqueezed out with the fingers. The medical ufes of fweet 
 Almonds are, to foften and obtund acrimony, and to render refinous fub- 
 fiances foluble in water and in the animal fluids. The Refins of Jalap, Scam- 
 mony, and others, triturated with Almonds, diflolve in water into anemulfion, 
 and in this form operate effectually, without producing the violent gripes and 
 other dangerous confequences, which they never fail to do when given by 
 themfelves. The Oil is an excellent medicine in cholicky and nephritic pains : 
 
 Half an ounce may be taken for a dofe, with thirty drops of the mineral ano- 
 dyne liquor. 
 
 Bitter Almonds yield alfo an Oil to the prefs, not bitter like the Almonds Bitter, 
 themfelves, but as taftelefs as that of the fweet kind, all the bitter matter re- 
 maining in the cake left after the exprefiion. I have made fundry experiments 
 for determining in what principle the bitternefs refides j but they have not 
 anfwered fo perfectly as could be wilhed. The Almond-cake was diftilled both 
 with pure water, and with water and Salt, and with highly rectified Spirit of 
 Wine. The diftilled waters were fcarcely bitter, but fmelt a little of the Al- 
 mond, and had a confiderable pungency : The diftilled fpirit difeovered 
 fcarcely any pungency or bitternefs, and differed very little in l'mell or tafte, 
 from the pure fpirit employed: Greateft part of the bitternefs, in all the diftil- 
 lations, was left behind, and continued in the infpiffated extracts (£). 
 
 Bitter Almonds are poifonous ter animals that come into the world blind, 
 particularly to birds. In the human body, they aCt as refolvents and aperi- 
 ents. Sweetened with Sugar, or made into an emulfion, they are an ufeful diu- 
 retic, and an anthelmintic for children. If taken freely, they occafion ficknefs 
 or vomiting. 
 
 THERE are fundry other fubftances from which grofs Oils are com- 
 monly extracted in large quantity for mechanic ufes, and which it were need- 
 lefs to examine in particular, as they have no other remarkable qualities than 
 
 thofe 
 
 (k) Bitter Almonds.] Great part of the bit- 
 ter matter diffolves, by digeftion, both in 
 watery and in fpirituous liquors ; and a part 
 arifes with both in diftillation. Spirit feerns 
 to diflolve, and water to elevate moft; but 
 it did not appear that the whole is difiolved 
 or elevated by either, or by the alternate 
 application of both. It is chiefly, if not 
 folely, in the matter which arifes in diftilla- 
 tion, that the noxious qualities of the bitter 
 Almonds reftde. A water diftilled from 
 them, when made of a certain degree of 
 ftrength, has been found from experiment 
 
 to be poifonous to brutes j and there are in- 
 ftances of cordial fpirits flavoured with them 
 being poifonous to men. In thefe prepara- 
 tions the aCtive principle has its aCIivity 
 probably increafed, by its feparation from 
 the foft infipid Oil and the farinaceous mat- 
 ter with which it was combined in the ker- 
 nel itfelf. The kernels of other fruits, that 
 have any bitternefs or particular flavour, ap- 
 pear to be impregnated with a fubftance 
 flmilar in quality to this poifonous principle 
 of bitter Almonds. 
 
39 ° 
 
 Plants and their Parts. 
 
 Almonds, thofe which depend upon the Oil, and as the principal differences of thefe kinds 
 u— -v— of Oils have been already mentioned. See p. 278, 322. 
 
 Oily Ve- 
 getables. 
 
 I. 
 
 Horse- 
 
 radish. 
 
 CLASS V. 
 
 Vegetables whofe prevailing principle is an ejjential Oil. 
 
 ANY of the fubftances of this clafs yield but a very fmall quantity of 
 eflential Oil: Neverthelefs, in this Oil refides the whole of their diftin- 
 guifhing ifnell and tafte. On diftilling them with water, all the adtive parts 
 of the fubjedt arife, partly impregnating the liquor, and partly feparating in 
 their proper oily form : On infpiffating the remaining decodtion, a mucilagin- 
 ous extradt is left, which, if not altogether infipid, has at leaft nothing of the 
 fpecific tafte any more than of the fmell or flavour of the original vegetable. 
 Redtified Spirit of Wine frequently elevates little or nothing in diftillation, the 
 Oil remaining in the extradt blended with the refinous parts : If this extradt is 
 boiled with water, the volatile Oil is diflipated as before, and only an infipid 
 and inodorous refinous mafs is left. To this clafs belong fome of the flavour- 
 lefs pungent fubftances, as Horfe-radifh and Muftard -feed ; fome ungrateful 
 pungents, as Garlic; fome of the aromatic plants, as Rofemary and Anife * 
 and fome of the foreign fpices, as Nutmegs. 
 
 HORSE-RADISH ( Raphanus rufticanus , armor aria, the Co chlearia folio 
 cubitali of Tournefort) is a root of common and well known ufe at table; but 
 its chemical ftrudture, the principle in which its pungency refides, and which 
 fo ftrongly affedts the organs of tafte and fmell, have been hitherto wholly un- 
 known. 
 
 The very foul of Horfe-radifh is an eflential Oil, which is fo ponderous as to 
 fink in the aqueous fluid that comes over with it : A confiderable part however 
 is imbibed by the water, fo as to communicate a ftrong impregnation : It is 
 highly pungent, but not fiery or hot like moft other eflential Oils ; as foon as 
 the firft impreflion of pungency is over, it leaves an agreeable fweetifhnefs upon 
 the tongue. It is on account of the avolation of this fubtile Oil, along with 
 the native watery moifture of the root, that Horfe-radifh lofes its pungency in 
 drying : The entire root may be preferved frefh in a cool place, efpecially if 
 covered with fand, for a confiderable time; but if the outer fkin be taken off, 
 the root fliced or fhaved, and laid in a moderately warm place, its adtivity is 
 quickly diflipated, and in this ftate it will not yield a Angle drop of Oil. 
 
 Eight ounces of the frefh root were reduced by drying to two ounces two 
 fcruples. Water extradls from this quantity one ounce of mucilaginous matter, 
 and fpirit takes up from the refiduum fifteen grains of Refin. The eflential 
 Oil amounts to nearly the fame proportion, befides what remains diflolved in 
 the diftilled water. Redtified fpirit, applied at firft, takes up feven drams from 
 eight ounces, and water extradls afterwards near three drams. Both the ex- 
 tracts are fomewhat fweetifh, the fpirituous moft fo. It has been faid that the 
 pungency of Horfe-radifh is covered by trituration with Almonds ; but this did 
 not anfwer upon trial. 
 
 GAR- 
 
Plants and their Parts. 
 
 S9 1 
 
 GARLIC ( Allium fativum C B .) is a plant of the Leek kind, cultivated n. 
 in gardens : It has long, flat, not tubulous leaves, and produces a fpherical Garlic. 
 
 duller of hexapetalous Lily-like flowers, each of which is followed by a roun- 
 difh leedveflfel. The only part made ufe of is the root; which confifts of a 
 number of white, coated bulbs, inclofed in a purplifh-red lkin, with a bulh of 
 fibres at the bottom : Such roots fliould be chofen as are not very tough or 
 compact. 
 
 Garlic has a ftrong fmell, and a fharp biting tafte. In many places, it is 
 employed in foods and fauces : The Eaftern nations are particularly fond of it. 
 
 As a medicine, it is a powerful refolvent and attenuant; and hence of good 
 fervice where the bread, ftomach, or inteflines, are obftrudted or over- 
 loaded with vifcid phlegm. Some have held it a fpecific in the gout; and 
 imagined, that it is the plentiful ufe of this root, which preferves the Jews from 
 that diforder. Ufed as a fuppofitory, it occafions a furprizing palenefs and 
 ficklinels of the face. 
 
 The fmell of Garlic is to many people unfupportable. There are fundry 
 fubftances which have been faid to take off both its fmell and tafte, as Cloves, 
 Cinnamon, Calamus aromaticus. Cardamom-feeds, Zedoary and Rue. On 
 trial, none of them was found to anfwer : They weaken or overpower the 
 fmell of the Garlic, more or leis in proportion to their own quantity, but do 
 not effedlually conceal it. Zedoary and frefh Rue cover the fmell more than 
 any of the others, and the Rue fomewhat more than the Zedoary. The anci- 
 ents pretended that fpiders had fuch an averfion to the fmell of Garlick, that if 
 inclofed in a circle of the roots, they would be unable to get over it : This alio 
 1 have tried, and found to be falfe. It is obfervable, that Arfenic and the 
 Phofphorus of Urine fmell like Garlic : Wherever we perceive an alliaceous 
 fmell, if no plant of the Garlic kind be there, we may be fure that it proceeds 
 from an arfenical matter. 
 
 Many have imagined that Garlic abounds with volatile Salt, and that this is 
 the caufe of its ftrong fmell. Experiments have flhewn, that the fmell of Gar- 
 lic refides in a very different principle, and that the confrituent parts of this 
 root are the following. (i.)A large quantity of watery moifture, amounting 
 to nearly two thirds of its weight; for two ounces of the frefh root were re- 
 duced by drying to five drams two fcruples. We cannot feparate fo much li- 
 quid matter by expreffion; four ounces of the frefh root yielded fcarcely one 
 ounce of juice : But nearly all that is loft in drying may be colledfed by diftil- 
 lation. ( 2 .) A confiderable quantity of mucilaginous or gummy matter. Two 
 ounces of the root being infufed and boiled in water, in a glafs body clofely 
 covered, and the water renewed fo long as it continued to extradl any thing 
 from the root; thefeveral infufions, mixed and filtered, yielded on infpiffation, 
 fix drams and a fcruple of gummy extradl. (3.) A fmaller proportion of unc- 
 tuous refinous matter. Two ounces, cut in pieces, and digefted in frefh par- 
 cels of highly redtified Spirit of Wine, yielded on infpiffating the tindfures, 
 only two drams and three grains of refinous extradl : This undtuous, tenaci- 
 ous, refinous fubftance, difcovers itfelf alfo during digeftion, being very apt to 
 precipitate and ftick to the veffel: To this are owing the precipitations which 
 
 juice 
 
392 P L ants and their Parts. 
 
 Garlic, juice of Garlic occafions in fome metallic folutions, and which have been erro- 
 ^ — -v— ' neoufly afcribed to a faline principle. That the refinous part is in lefs quantity 
 than the gummy, appears further from hence ; that rectified fpirit, digefted on 
 the matter left by water, takes up only one fcrupleand feven grains; but water 
 digefted on the matter left by fpirit, took up two drams, two fcruples and two 
 grains. (4. ) An indifioluble earthy matter, amounting in either method of ex- 
 traction, to two fcruples and one or two grains upon two ounces. (5.) The 
 fifth and principal ingredient, the very foul of the Garlic, is an effential Oil. 
 In this alone refides the fmeil, and the tafte, and all that diftinguifhes the 
 Garlic. 
 
 The quantity of Oil is fmall, but its activity and penetrancy are fo much 
 the greater : Its fmeil is abominably ftrong. On diftilling with water thirty- 
 two ounces of the root, fcarce half a dram of Oil could be collected : It is quite 
 ropy and thick, and difficultly feparable from the aqueous fluid : The water 
 diftilled off in making the watery extraCt after fpirit, difcovered alfo a confi- 
 
 derable fmeil, but of a fetid kind different from that of Garlic A diftilled 
 
 fpirit and faturated tinCture are recommended by fome as prefervatives againft 
 peftilential infection. From the alexipharmac virtues attributed to this root, 
 it has received the name of Theriaca rujlicorum. 
 
 III. 
 
 Onions. 
 
 THE common Onion (Cepa 'vulgaris C. B.) is another root, whofe cha- 
 raCteriftic principle has been hitherto unknown. It is remarkable of the Oil of 
 this root, that it remains all diflolved in the diftilled Water, which it impreg- 
 nates with an exceffively ftrong fmeil : On diftilling twelve pounds of Onions, 
 peeled and cut in pieces, I could not leparate any Oil, though all the aCtive 
 parts of the root were collected in the Water. 
 
 This root contains a large quantity of aqueous moifture : Eight ounces 
 were reduced by drying to eight drams and a half. The matter diffipated in 
 the exficcation was chiefly Water, with a little of the more fubtile part of the 
 Oil. The Onions, when about half dry, fmelt like Rue. 
 
 An ounce of the dry root yielded with rectified Spirit fix drams of extraCt, 
 and afterwards with Water one dram eighteen grains : Another ounce, treated 
 firft with Water, gave fix drams thirty-five grains, and afterwards with Spirit 
 half a dram : The indifioluble refiduum weighed in the firft cafe two fcruples 
 fixteen grains, in the latter eight grains more. The diftilled Spirit is fome- 
 what impregnated with the Oil of the Onion, difcoverable rather by its tafte 
 than by its fmeil ; the more fubtile odorous parts having been diffipated in 
 the previous exficcation. The fpirituous extraCt taftes ltrongly of the Onion : 
 This is the ftrongeft preparation in point of tafte, and the diftilled Water in 
 
 fmeil This root, befides its culinary ufes, has been employed medicinally 
 
 as a refolvent and diuretic, in cachexies, dropfies, nephritic cafes, &c. 
 
 IV. THE roots of Masterwort, Imperatoria , Aftrantia, Oftrutium y (Jmpera- 
 Master- toria major C. B.) have a pungent, aromatic tafte, and a very ftrong, agreeable 
 wort, fmeil : They are long, knotty, unequal, of a brown colour without and a yel- 
 t — - j lowifh-white within, full of greeniffi-yellow fpecks, particularly towards the out- 
 fide, of a fparkling manifeftly refinous appearance, and unCtuous to the touch. 
 
 5 The 
 
Plants and their Parts. 
 
 The diftinguifhing tafte as well as fmel! of the root re Tides in an effential Master- 
 Oil, which is fmall in quantity but of great activity : Sixteen ounces fcarcely wort. 
 afford more than half a dram. The diftilled fpirit frnells a little of the root, but 
 not near fo ftrongly as the diftilled water, pure fpirit elevating only fome of the 
 more fubtile parts of the Oil. The fpirituous extract on the other hand is 
 much ftronger than the watery, the latter having loft in the evaporation all the 
 Oil or fpecific matter of the Mafterwort, of which greateft part is retained by 
 the former. An extract made by fpirit after water is a mere grofs infipid 
 Refin ; and an extradl made by water after fpirit is merely mucilaginous. 
 
 An ounce of the root gave four drams_ ten grains of watery, and afterwards 
 half a dram of fpirituous extract : Rectified fpirit applied at firft extracted from 
 the fame quantity two drams and a half, and water afterwards five fcruples • 
 
 The indiffoluble earthy part weighed in the firft cafe three drams twenty grains, * 
 in the latter three drams fifty grains. 
 
 T HE roots of Angelica are nearly fimilar iri quality to thofe of Mafter- V. 
 wort : They have a pungent, agreeable, bitterifh tafte, and a ftrong aromatic Angelic a. 
 fmell, fomewhat of the mufky kind. Their activity refides in an effential Oilu— -v-w 
 and a refinous matter : The Oil is obtained by diftillation with Water : On 
 digefting or infufing the roots in Spirit of Wine or in Water, both the Oil and 
 Refin are extradled, wholly by the former, and in part by the latter. 
 
 Thefe roots, like thofe of moft of the umbelliferous plants, are very apt to 
 be preyed upon by Worms, to become carious, and fall into powder. So long 
 as they are but merely worm-eaten, and not powdery, they are as fit for mak- 
 ing the effential Oil, or the fpirituous tindture and extradl, as in their moft 
 perfedt ftate •, and even more fo j the infedls preying firft, not upon the refi- 
 nous and oily, but on the earthy and mucilaginous parts : When fuch roots 
 are made ufe of, care muft be taken to beat out, as much as pofiible, the 
 worms and duft. The beft method of preferving Angelica for any consider- 
 able length of time, is, to dry it thoroughly, then pack it up clofe in glafs or 
 other compadt veffels ; which are to be carefully ftopt fo as to prevent the ad- 
 million of air, and kept in a dry place. 
 
 THE moft adlive part of Angelica is the root ; of Anise, the feeds. Ank 
 feed contains, befides its eflential odorous Oil, a grofs one of the expreflible 
 kind: The effential Oil, and the fmell and tafte of the feeds which depend 
 upon it, are confined to the outer thin fkin : The inner kernel, which is com- 
 monly divided longitudinally into two portions, has little or no fmell, and ex- 
 ceeding little tafte : In this refides the grofs Oil, naturally inodorous, and in- 
 fipid, but which, neverthelefs, in its feparation from the feed by the prefs, 
 brings with it a part of the effential Oil, fo as to become ftrongly impregnated 
 with the peculiar flavour of the Anifeed : Its colour is greenifh. 
 
 The effential Oil, though mild in tafte, has an extremely ftrong fmell, 
 which it communicates to whatever it touches, in fuch a degree, as fcarcely, 
 or not at all to be overpowered. It coagulates in the cold, becoming thick 
 like butter, a property obferved in very few of the effential Oils: The coagu- 
 lation is generally aicribed to its being diftilled by a ftrong fire ; but I have 
 
 E e c drawn 
 
 VI. 
 
 Anise eo. 
 
394 
 
 Aniseed. 
 
 Plants and their Parts, 
 
 coagulated 
 
 VII. 
 
 Stellated 
 
 Anise. 
 
 drawn from Anifeeds, by a bare digefting warmth, an Oil which 
 even iti fum'mer. The addition of a little common Salt is of fervice in the 
 dilli 1 1 at ion of the Oils of many vegetables : But for Oil of Anifeed, that addi- 
 tion is by no means to be employed ; this feed yielding only half as much Oil 
 when diftilied with Salt, as it does without. This Oil is drawn in large quan- 
 tity about Magdeburg, and is in general greatly adulterated. We may fome- 
 times buy an ounce of the Oil for nearly the fame price as a pound of cne 
 feeds ■, though a pound of the feeds yields only about half an ounce, and the. 
 reflduum is of no ule. It is remarkable of this Oil, that it diftblves Sulphur 
 in greater quantity than any other Oil, exprefled or diftilied : Digefted with a 
 compofition of Sulphur and fixed alcaline Salt, it imbibes a large portion of 
 Sulphur from the alcali, fo as to acquire a thick confiftence, whilft other dif- 
 niled Oils take up very little, and exprefled ones fcarce any. 
 
 A N exotic fruit, compofed of feven or eight, and fometimes nine capfules 
 fet in form of a ftar, is diftinguifhed in the {hops by the name of Anifum Jlel- 
 latum , Stellated or Starry-headed Anise ; its tafte and fmell being ex- 
 actly fimilar to thofe of the common Anifeeds, but ftronger. This fruit is 
 called by fome Anifum Indicum , Chinenfe , Rufficum , Mofcoviticum , Peregrinum ^ 
 Philip pin arum infularum , Semen badian , Fccniculum fmenfe , Cardamonum fiberienfe. 
 Of the plant which produces it we have no account, except that Clufius de- 
 fcribes and figures a fmall branch received from the Philippine Iflands with 
 fome of the fruits upon it : It is commonly fuppofed that this fruit, and the 
 wood called in Holland from its fmell Anife-wood, are taken from one tree. 
 
 The ftarry capfules are fomewhat broad at the end where they are joined, 
 and pointed at the oppolite one ; externally hard, rugged, and unequal, and 
 ofareddilh brown colour like ruft of Iron; internally finooth and glofiy : 
 They commonly open on the upper fide, and difcover an oblong kernel, about 
 the fize of Colocy nth- feeds, covered with a finooth brownifh fkin fomewhat 
 darker than that of Linfeed, internally yellowifh and brittle. Herman relates, 
 that the fmell and tafte of this fruit is confined wholly to the outer capfules, 
 t-he kernels having none. The fkin of the kernel has indeed neither tafte nor 
 fmell, but the inner fubftance is in both refpeds ftronger than the capfules ; 
 and in thefe particulars the fteilated Amfe differs remarkable from the 
 common. 
 
 To determine this point more fatisfaCtorily, I diftilied equal quantities of 
 the kernels and of the capfuies, with equal quantities both of rectified Spirit of 
 Wine and of Water : The diftilied liquors were nearly equal in degree of fmell 
 and tafte, but in the diftillation with Water, a good deal more Oil was ob- 
 tained from the kernels than from the capfules a fore proof that the former 
 is the moft aCtive part. The kernel contains alfo an expreftibie Oil, like the 
 common Anifeeds; but as this Oil is lodged in the fame part, and naturally 
 blended, with the efientiaS, it proves, when feparated from the feed' by ex- 
 preflion, very flrongly impregnated with its tafte and fmell. 
 
 The fteilated Amfe is applicable to the fame purpofes as the common : It is 
 ufed chiefly, in the form of cinCture, and of a watery infufion or tea, as an ex- 
 pectorant, carminative and ftomachic. 
 
 SMALL- 
 
Plants and their Part s. 
 
 395 
 
 SMALL AGE, Apium , Apium pal 'ujire , Paludapium, Eleofelinuin^ is an um- VIII. 
 belliferous plant, growing wild in marfliy places. The Garden -celery, of S mallage 
 common ufe in food, is luppofed to be no other than the wild Stnallage im- 
 proved by culture. 
 
 The mo ft active part of Smallage appears to be the Seeds. Thefe, like moft seeds, 
 of the feeds of umbelliferous plants, contain two kinds of Oil, an effentia! one 
 in which their diftinguiffiing flavour refldes, and an exprefiible one of little 
 fmell or tafte : The firft is lodged in the fhell, the other in the kernel of the 
 feed. Sixteen ounces of Smallage-feeds yield about two fcruples and a half of 
 effential Oil. One ounce of the feeds afforded, with Water, three drams two 
 grains of gummy extradt, and afterwards with redtified Spirit twenty-four 
 grains of Refin : Another ounce, treated firft with Spirit, gave five fcruples 
 fix grains of refinous, and afterwards with Water two fcruples feventeen grains 
 of gummy extradt. It is remarkable, that the refinous extradts are of a fine 
 green colour. 
 
 Fifty-feven ounces of the frefh leaves of Smallage yielded on expreffion 
 thirty-four ounces of juice-, from which were obtained, by a tedious crystal- 
 lization, one dram and a few grains of a foiid concrete (lightly faline to the 
 tafte, very difficultly foluble in Water, and which laid upon burning coals ap- 
 peared more of the earthy than faline kind. Of the dry leaves, about one half 
 is earthy or indiffoluble : An ounce yielded with Water three drams forty-fix 
 grains of gummy extradt, and afterwards with Spirit fcarce half a dram of a 
 refinous one : Another ounce, treated firft with Spirit, gave two drams two 
 fcruples and a half of refinous, and afterwards one dram feventeen grains of 
 gummy extradt. In diftilling a large quantity of the leaves with Water, a 
 fmall portion of effential Oil is obtained j but none could be collected on diff 
 tilling an ounce. 
 
 An ounce of the dried roots yielded half an ounce of watery, and afterwardsRoots, 
 half a dram of fpirituous extradt: Another ounce, on inverting the order of 
 applying the menftrua, gave a dram and a half of fpirituous, and three drams 
 
 of watery extradt With regard to the medical virtues of this plant, the roots 
 
 are accounted aperient, and the feeds carminative. 
 
 THERE is a poifonous plant, greatly refembling Smallage, growing in Cicuta 
 the fame places, and which has too often been fatally miftaken for it : The Aouatica. 
 ftalks, the flowers, the feeds, the roots, the juice, the fmell and the tafte, are 
 in both plants alike, and only the leaves different. The poifonous herb ap- 
 pears to be but imperfedtly known : The botanifts themfelves have referred it 
 to many different genufes, fome to that of Apium, fome to Anagallis , others to 
 Phellandrium , CEnanthe , Myrrhis , Cicuta , Cicutaria , Petrofelinum , Aconitum , Siam; 
 
 Some give it the fame name with Smallage, Apium palujire , or aquaticum . A 
 certain phyfician of Regen fp urg, who fome years ago opened a ftudent that had 
 been killed by it, calls it Aconitum caruleum petrojelincide, odore Angelica‘s radice 
 ireos fimili, Cafp. Batch, pin. but unfortunately no luch name is to be met with 
 in the writings of Calpar Bauhine, or any other Botanift. 
 
 E e e z Tits 
 
396 P l a n t s and their Parts. 
 
 Cicuta The poifonous plant is the Shim erne a folio of Cafpar and John Bauhine, 
 Aquatica.^/^ alterum of Dodonaeus, the Slum alterum olufalri facie of Lobel, who has 
 given the mofc dill in hi figure, the Sion aquaticum , rngofis foliis trifidis.. multi - 
 fidis £? dentatis of Morifon, the Cicuta aquatic a of Gefiner, the Slum palujlre alterum 
 foliis ferrat is of Tournefort, Cicutaria of Rivinus, Sum majus alterum angufti- 
 folium of Parkinfon, and Shim majus angujlifolium of Tabernaemontanus. It is 
 called in Saxony Bartzen-kraut , about Berlin Berfte-kraut (a name applied alio 
 to other poifonous plants) in the Netherlands Precede Water-eppe , in Italy 
 Gorgolejlro , in Spain Rabacas , and in England Long-leaved Water- 
 Hemlock.. 
 
 It differs from Smallage in the leaves being long, flender, and deeply cut, 
 commonly into three fegments : Thofe of Smallage are cut in the fame manner, 
 but the fegments are fhort and broad. The roots of this plant are at firft hol- 
 low and green, and lined internally with a fhining white matter: By age they 
 become harder and more folid, and change their green colour to a pale yel- 
 low ilh : When full grown, they are as large as the fill. They have a num- 
 ber of fibres, like the common Celery-root, efpecially at the bottom, by which 
 they are fattened to the earth, at the bottom of the Water wherein they are 
 commonly produced : They are often however loofened and carried off by the 
 Water •, and too often have been taken up and eaten for Celery, of which a 
 melancholy inftance happened in this neighbourhood [Berlin] fome years ago: 
 Their taffe and fmell are the fame, except that the fmeil is more penetrating, 
 and that after the firft agreeable tafte is over, fomewhat biting is left upon 
 the tongue. 
 
 Their poifonous quality refides in an orange-yellow juice, which is diftri- 
 buted indeed through the whole plant, but accumulated molt plentifully in 
 the roots. I took an old, yellowifh, juicy root, and paring off the outer part 
 which abounds mod with juice, preffed out fome of the yellow liquor : A 
 little of this, mixed with fome portion of the root in fubftance cut fmall, be- 
 ing given to a ftrong young dog, he was in two minutes feizecl with violent 
 convulfions : He then begun to vomit exceflively, but was not relieved ; in 
 nine minutes he died. I know of no poifon fo abtive and fo fudden, excepting 
 the fubtile fumes which fly off from fermenting liquors, and the vapour of 
 burning Charcoal confined : The mo ft violent of the mineral poifons, Arfenic 
 and Corrofive Sublimate, are not equal to it. In a few minutes it brings on 
 high convulfions, lofs of the fenfes, raving, fwelling of the eyes, inflamma- 
 tions, death : On difleiftion, the lfomach is fometimes found corroded, the 
 heart flaccid, blood extravafated, the tefticles of a purple and blackifh red co- 
 lour : In others, there was fcarcely any thing preternatural to be obferved. 
 See Wepfer’s treatife De Cicuta Aquatica. The only means of preventing the 
 terrible effects of this poifon are, immediate vomiting, not by acrid medicines, 
 but by taking large quantities of Milk, Oil, Fats, and if thefe fail, fome Ipe- 
 cacoanha or other mild emetic : Glyfters of Water, Milk, or Water-gruel, 
 with Oil or butter, are alfo to be repeatedly injebted and gentle diaphoretics 
 fubjoined. 
 
 The young roots, as containing lefs of the yellow juice, are lefs dangerous than 
 the old : The juice of a young green root being given to a dog, he loon fell 
 
 down,. 
 
Plants and their Parts. 397 
 
 ■down, and appeared in great pain, but after vomiting feverai times, Ire grew Cicuta 
 better, and in a few days was well. By drying, the poifonous quality is. greatly Aquatica. 
 abated, if not totally deftroyed. 
 
 On a chemical analyfis, both the leaves and roots of this plant are found to 
 contain a large quantity of watery moifture. Four ounces of the frefn roots 
 were reduced by drying to three drains and a half •, from which were obtained 
 two drams of fpirituous and half a dram of watery extract; only one dram of 
 earthy matter remaining from the whole four ounces. The leaves loft more hi 
 drying, and yielded leis earth than the roots : The quantity of watery extract 
 was two drams from four ounces : The refiduum gave but half a fcruple to 
 Spirit. Sixteen ounces of the leaves yielded in expreffion ten ounces of juice , 
 which, on being infpifiated, left no more than a fcruple of folia matter. 
 
 COMMON Fennel Seed ( Foeniculum vulgare German kum C. B.) is of a JX. 
 fine greenifh colour, and an oval figure with feverai longitudinal furrows iFejwnelj, 
 Every feed parts longitudinally, when dry, into two. It has a ftrorg aro- common, 
 matic fmell and tafte, fomewhat like thofe of a mixture of Anife and Dili- 
 feeds with a little Angelica : To thofe feeds alfo it is nearly fimilar in medici- 
 nal virtue. 
 
 It contains a portion of expreftible, as well as an efiential Oil •, the fpecific 
 qualities of the feed refide in the latter, which has a ftrong penetrating fmell, 
 but is not very fubtile or volatile, for pure rectified Spirit of Wine carries up 
 in diftillation exceeding little of it. A confiderable portion of oily matter fe- 
 parates during the inipiffation of the fpirituous tindlure of the feeds •, the Oil 
 flowing at top, whilft the more purely refinous parts fall to the bottom. 
 
 On infpifiating a tir.&ure drawn from two ounces of bruifed Fennel-feeds, 
 the pure refinous extradl amounted only to four fcruples and four grains, and 
 the Oil to two drams : Both the Oil and the Refin were of a fine green colour. 
 
 This extract fmelt and tafted exceeding ftrongly of the Fennel, little or no- 
 thing of its flavour having been difiipated in the evaporation, and though a 
 part was imbibed by the grofs Oil, yet much remained ftill in the extradb The 
 refiduum of the feeds yielded with Water two drams of mucilaginous extract, 
 leaving undifiolved ten drams and a fcruple of earthy matter. 
 
 The fame quantity of the feeds, digefted and boiled firft with Water, gave 
 four drams and a fcruple of a mucilaginous extradt; after which, rectified 
 Spirit extracted one dram of Refin ; the refiduum amounting, as before, to ten 
 drams and a fcruple. In diftillation with Water, about a fcruple of efiential 
 Oil w'as obtained from two ounces. The firft watery extradl had very little 
 tafte : That made after Spirit was fomewhat bitterifE : The fpirituous extradl, 
 made after Water, could not be reduced to a dry confiftence on acount of 
 the grofs Oil that was blended with it : To the tafte it was difagreeably 
 oily. 
 
 The leaves of Fennel are nearly fimilar in flavour to the feeds, but lefs grate- 
 ful. They yield in diftillation a fmall quantity of efiential Oil : That obtained 
 from the upper leaves is remarkably finer, lighter, and more fubtile than that 
 of the lower : One fwims on Water, whilft the other finks. 
 
 & The; 
 
and Sweet. 
 
 Plants and their Parts. 
 
 The root is about the thicknefs of the finger, commonly (freight, of a whr- 
 tifh colour with a woody pith in the middle. It has a fweetifii aromatic tafte. 
 and fmell, and is fupofed to pofiefs an aperient virtue. 
 
 Sweet Fennel ( Faniculum dulceC. B.) is raifed chiefly in Italy. The feeds arc 
 larger than thofe of the common fort, and of a fweeter and more agreeable 
 tafte : Their diddled Oil alfo is confiderably more graceful. In other refpedts 
 they agree nearly with thofe of the foregoing fort. The roots of this fpecies 
 are u led by the Italians in food. 
 
 X. C H E RV I L (Ch (trophy Hum fativum C. B.) is a culinary herb, of a (lightly 
 Chervil, aromatic tafte, and a not difagreeable fmell : It is faid to be diuretic, and of 
 g re »t fervice in dropfies. 
 
 It contains a large quantity of watery moifture : Sixteen ounces of the frefh 
 leaves were reduced by drying to one ounce feven drams. Diddled with water, 
 it gives over an effential Oil, final 1 in quantity, but poffefling all the a&ivity 
 of the herb: From nine pounds I did not obtain quite half a dram; part was 
 colourlefs and fwum on the water ; part was of a yellowi(h-brown colour and 
 funk. I have gained alfo from fundiy other vegetables two kinds of Oil in 
 one operation •, a point which has not hitherto, that I know of, been confidered, 
 or indeed obferved by any. It is commonly fuppofed, that only the Indian 
 fpices yield an Oil fo heavy as to fink in water. 
 
 The Oil of Chervil, even that which fwims, is not very volatile, for recti- 
 fied fpirit brings over nothing of it : A confiderable part of it, however, is 
 diflipated in drying along with the watery moifture of tne herb, and elevated in 
 diflillation by a phlegmatic fpirit: Hence the fpirituous extract made either 
 from the frefh or dry leaves, has but little of the flavour of the Chervil ; for 
 when frefh leaves are ufed, their watery moifture, rendering the fpirit phleg- 
 matic, enables it to carry up the Oil. 
 
 From an ounce of dry Chervil were obtained three drams and one fcruple of 
 watery, and afterwards three drams of fpirituous extraift. On inverting the 
 order of applying the two menftrua, I gained, from the fame quantity, three 
 drams ten grains of fpirituous, and afterwards a dram and a half of watery 
 extrabt. 
 
 The feeds of this plant dilcover no confiderable tafte or fmell, either in fub- 
 ftance, in their diddled water or fpirit, or in their extracts. An ounce gave a 
 dram and a half of watery, and thirty-four grains of fpirituous extradl: Ano- 
 ther ounce, treated contrariwiie, gave only thirty- two grains of fpirituous, and 
 one dram thirty-three grains of watery extrabl. 
 
 BETONY (Bet onica purpurea C. B.) has very little tafte or fined; but 
 Betony w Eat it has, refldes in an effential Oil, as being elevated by water in diftilla- 
 , , tion, though we can fcarcely obtain any feparable Oil upon diddling a mode- 
 
 rate quantity of the herb. 
 
 This Oil does not ariie with rectified fpirit, and hence the fpirituous extrad: 
 has a confiderable tafte, whilft the watery is almoft inflpid. The fpirituous 
 extradions pofiefs the green colour of the plant, whilft the watery have nothing 
 of it j and indeed vegetable greens in general feem to refide in a refinous mat- 
 ter. 
 
Plants and their * Parts. 3gq 
 
 ter, oj at lead in a fubftance that is foluble inSpirit of Wine and not in Betony. 
 
 An ounce of the dry leaves of Betony yielded with rectified fpirit three drams 
 two fcruples, and afterwards with water two drams one fcruple of extract: 
 
 Another ounce, treated firft with water gave five drams, and afterwards with 
 fpirit one •, fo that which foever of thefe menftrua is firfi applied, fix drams are 
 extracted, and two drams left. 
 
 This plant has been celebrated for abundance of medicinal virtues, but does 
 not promife to have any confiderable activity : Its principal ule is as an ingre- 
 dient in herb fnuffs, in compofitions for fmoking, and as a fubftitute to Tea. 
 
 It is obiervable, that the roots of Betony differ greatly from the other parts of 
 the plant ; they operate both upwards and downwards, and feem to approach to 
 the nature of the roots of Hellebore. 
 
 DITTANY of CRETE {Origanum Creticum tatifolium tomentofum feu xiL 
 ditfamnus Creticus Tourn.) is a plant with fmall woolly leaves, and monopetalous, Dittany 
 labiated, purple flowers fet in fcaly fpikes on the tops of the (talks. It grows 0 f Crete, 
 wild in the ifland Crete or Candy, and is raifed in gardens in l'ome parts of > _ > 
 
 Europe : The greateft quantities are brought into Germany by the way of 
 Venice, tied up in bundles, which are often mouldy or mixed with foreign 
 matters in the infide. 
 
 The leaves, when in perfection, yield a fmall quantity of effential Oil, about 
 half a dram at moft upon fixteen ounces, of a yellow colour, and an extremely 
 ftrong penetrating aromatic knell and tafte ; it coagulates in the cold into the 
 appearance of Camphor. Rectified Spirit of Wine elevates very little of the 
 Oil, the difiilled fpirit having fcarcely any fmell or tafte. The fpirituous ex- 
 tract is moderately warm and fomewhat bitterifh •, the watery is in larger quan- 
 tity, but of little tafte. 
 
 An ounce yielded with water two drams and a fcruple of extraCt, and after- 
 wards with fpirit two fcruples four grains : The fame quantity, treated firft 
 with fpirit, gave a dram and a half, and afterwards with water four fcruples. 
 
 The green colour of the leaves refidesin the Re fin : It is not indeed very di- 
 ftinguifhabie in the fpirituous extraCt made at firft, the gummy matter which 
 the fpirit takes up along with the Refin diluting and covering it ; but an ex- 
 tract made by fpirit, after the gummy parts have been feparated by water is 
 plainly green. 
 
 ROSEMARY {Rofmarinus hortenfis angujliore folio C. B.) is a fragrant XI If 
 plant, of common ufe in perfumes, and in medicine as a corroborant of the Rosemary, 
 nervous fyftem : Hungary-water is a vinous fpirit impregnated by diftillation v— — 
 with the flavour of the flowers. 
 
 The only aCtive principle in this plant, is the efifential Oil : The gummy 
 extraCt, diverted of the Oil, has no remarkable tafte any more than fmell : 
 
 The refmous extraCt, as pure fpirit elevates but a part of the Oil, retains a 
 part, and not an inconfiderable one, of the flavour of the herb. In the form 
 of an infufion or tinCture, its fragrance may be communicated both to water 
 and to fpirit. 
 
 The 
 
400 
 
 Plants and their Part s'. 
 
 Rosemary. The flowers of Rofemary are fuppofed to be more odoriferous, or at leaft of 
 ' a pleafanter odour thap the leaves; but ftriftly fpeaking, the flowers are ino- 
 dorous. The coloured petala, carefully picked from the cups, have neither 
 fmell nor tafle: Such as difcover any degree of t.hefe qualities have received 
 them from the oily matter of the cups in gathering ; the veflcles, in which the 
 Oily matter is lodged, being very eaflly burft. 
 
 An ounce of the flowers, with the cups, yielded to reflified fpirit fevers 
 fcruples of extrad, and afterwards to water two drams and a half: Water ap- 
 plied firfc took up from the fame quantity four drams, and fpirit afterwards one 
 dram. Both the fecond extrads had neither tafte nor fmell : The firft watery 
 extrad had very little of either; the firft fpirituous a notable fhare of both 
 together with the green colour of the flower cups. It is obfervable, that the 
 fecond fpirituous extrad appeared powdery, and not of a truly refmous tena- 
 city. The d iftilled water fmelt and tailed confiderably of the Rofemary, but 
 from the quantity made ufe of in this experiment no aduaiOil could be col- 
 leded. 
 
 The leaves are richer in Oil : From forty-eight ounces I obtained three 
 drams and half a lcruple ; a proportion fmall indeed, but greater than the 
 flowers have been known to yield. An ounce of the leaves afforded with fpirit 
 three drams of extrad, and afterwards with water one dram five grains: On 
 inverting the order of applying the menftrua, the watery extrad weighed three 
 drams, and the fpirituous one dram ten grains. The green colour of the 
 leaves, as that of the flower cups, was retained in the fpirituous extrad. 
 
 Tournefort obferves, that thofe forts of Rofemary, which produce neither 
 flowers nor feeds, and which have very hard Ihrubby ftalks and long narrow 
 leaves, fmell ftrongly like Camphor, and yield on diftilling a large quantity 
 for Oil, a portion of adual Camphor. 
 
 XIV. 
 
 Orange 
 
 Flowers. 
 
 THE flowers of the Orange-tree yield an highly odoriferous eflential 
 Oil, but in very fmall quantity. This Oil is very fubtile and volatile : It 
 arifes in diftillation with redified Spirit of Wine by the heat of a water-bath, 
 and exhales in the air upon barely drying the flowers, leaving them nearly in- 
 lipid as well as inoJorous. In feveral parts of Italy, exprefled Oils are impreg- 
 nated with the fragrance of thefe flowers for the purpofes of a perfume. (See 
 page 323.) The diftilled water of Orange flowers is commonly called Aqua 
 naphee. 
 
 XV. 
 
 Saffron. 
 
 T H E Saffron plant (Crocus fativus C. B .) produces a purplifh blue flower, 
 whole ftyle or piftil is divided at top commonly into three flefhy filaments of a 
 deep orange red colour : In fome plants there are fix filaments, three pale and 
 three deep coloured. The high coloured parts, carefully picked, dried on 
 papers, and prefled into cakes, are the Saffron of the fhops ; an aromatic of 
 common ufe both for medicinal and culinary purpofes, laid to be peculiarly 
 exhilarating, antifpafmodic, lerviceable in diforders of the breaft, CxV. 
 
 There is no part of the world that produces better Saffron than England : 
 The German writers who hold the Hungarian and Auftrian to be the beft, 
 were probably unacquainted with the Englifh, the exportation of it being pro- 
 hibited. 
 
Plants and their Parts. 401 
 
 habited. The bed Saffron is in long broad filaments, of a deep red colour, Saffron. 
 without any yellow parts, moderately dry, yet flexible and foft to the touch *, dif- ■ •v— 
 ficultly pulverable ; of a ftrong and an agreeable fmell, efpeciallyat a diftance ; 
 affecting the eyes, fo as to draw tears from them, and of a pungent and fome- 
 what bitterifh tafte: It readily impregnates the hand with its fmell, and (tains 
 
 the moift hand with a deep yellow colour. The Spaniards are faid to commu- 
 nicate the unduofity expeded in it by adual Oil •, and fome, to increafe its 
 weight by the admixture of Carthamus flowers, and even of Litharge. 
 
 It is obfervable, that water and fpirit almoft equally extrad the virtue and 
 colour of Saffron ; and that water improves the fmell and heightens the colour, 
 whilft fpirit feems rather to weaken both. I dried two ounces and a half of the 
 beft Saffron, in the heat of a water-bath, and colledecl therefrom half an 
 ounce of liquor of an exceeding ftrong fmell, but which had no appearance of 
 any fubftantial Oil : It is this vapour of the Saffron which affeds the head, and 
 disorders the fenfes. The dried Saffron, which weighed juft two ounces, was 
 divided into two equal parts. I diftiiled redified fpirit from one ounce, and 
 pure water from the other : The fpirit had no perceptible fmell or tafte of the 
 Saffron: The diftiiled water fmek ftrongly of it, though not fo ftrongly as 
 
 that which exhaled in the drying. Neverthelefs, upon infpiffating the liquors 
 remaining after the two diftillations to the confidence of extrads, the watery 
 extrad was not only in larger quantity and of a deeper colour, but of a ftronger 
 fmell than the fpirituous ; a plain proof of the power of fpirit in covering or 
 concealing the fmell and colour, and of water in heightening or calling them 
 forth. That the fpirituous extrad poffeffed thefe qualities in a greater degree 
 than the watery, though it did not exert them, is evident from the circum- 
 fiances of the experiment, the Saffron in both cafes having loft them: The 
 following experiment is a further proof of this, and of the different powers of 
 the two menftrua. The fpirituous extrad, fo pale and fo inodorous, on being 
 diffolved in water (for either menftruum diffolves nearly all that the other has 
 extraded) gives a deeper colour, and acquires a much ftronger and more agree- 
 able fmell than the watery ; and on the other hand the watery extrad, diffolved 
 in redified fpirit, communicates but a pale tindure, and is hardly any longer 
 to be fmek at all. 
 
 With regard to the quantity of extrads, an ounce of dried Saffron yielded 
 with water fix drams, and afterwards with fpirit only one fcruple, five fcruples 
 remaining undiffolved. An ounce treated at firft with fpirit gave five drams 
 and one fcruple, and afterwards with water one dram half a fcruple, the refi- 
 duum weighing a dram and a half. The firft fpirituous extrad, pulverized 
 and digefted in a fuitable quantity of water, diffolved entirely : The firft wa- 
 tery extrad, digefted in fpirit, left twenty-four grains of a colourleis matter 
 like fand. 
 
 THE Lesser Cardamom is the fruit of an Eaft-lndian plant, called in XVI. 
 the Hortus Malabaricus Elettari. It is a triangular membranous capfule, of a Cardamom. 
 yellowifh-white colour on the outfide and white within, containing about twelve 
 or fourteen irregularly angular feeds lodged in three cells : Each feed is covered 
 with a purpiifh or reddifh- brown fkin which eafiiy comes off the internal fub- 
 
 F f f ftance 
 
Plants and their Parts. 
 
 fiance is white : When the feeds are of a greenifh colour on the outfide, and 
 rattle upon fhaking the capfule, the fruit has been gathered unripe. 
 
 Thefe feeds are an agreeable pungent aromatic : An ounce yields about a 
 fcruple ofeffential Oil, containing the whole of their pungency and lmell, with 
 fourteen or fifteen grains of refmous, and forty-five grains of mucilaginous ex- 
 tract The hufks are fimilar in flavour to the feeds, but much weaker ; no 
 adtual Oil can be colledted from them, though the diftilled water fmells ftrongly 
 of the Cardamoms : They contain however more foluble matter than the feeds $ 
 an ounce yields above a dram of watery, and about twenty-five grains of fpi- 
 rkuous extract. 
 
 There is a large and a middling fort of Cardamoms, differing a little in ap- 
 pearance, and more confiderably in their quality. The capfules of the large are 
 of a triangular figure, and Hand on leparate pedicles, like thofe of the forego- 
 ing, but are commonly much darker in colour : The middling grow in du- 
 ffers, are paler coloured than the one and darker than the other, in figure 
 round, with three feams or furrows at the junctures of the membrane which 
 parts them internally. Both thefe are much weaker than the fmall fort: They 
 nearly agree with it in regard to the quantity of watery and lpirituous extracts, 
 but fcarcely afford any feparable Oil, particularly the large kind. 
 
 CINNAMON is the bark of a tree of the Bay kind, growing in the 
 ifland Ceylon, called by Hermann Laurus zeylanicus bciccis calyculatis. Though 
 the bark is one of the moft grateful lpices, the wood is infipid and inodorous, 
 and ufed only as firewood : The root is impregnated with aromatic matter, and 
 yields in diftiilation not only an dfential Oil, but a portion of Camphor. The 
 bark is- taken off twice a year, inthefpring, before the tree begins to bloffom, 
 and in autumn, after the fruit has fallen: It is taken only from young trees, 
 that of the old being woody and bitterifii. 
 
 It has been obferved that the thin membrane, which invefls the internal fur- 
 face of the bark, is vaftly ftronger in fmell and tafle than the bark itfelf: Some 
 fuppofe that the aromatic matter is originally confined wholly to this mem- 
 brane, and thence communicated to the exterior parts in drying. Lemery is of 
 opinion, that Cinnamon recives all itsfrnell and tafle from theablion of the fun 
 in its exficcation : This can be no otherwife true, than as the adtive parts are 
 more concentrated by the difiipation of the watery : Hermann affures us, that it 
 is not in the fun but in the fhade that the bark is dried. 
 
 Cinnamon has a very agreeable, pungent, fomewhat aflringent tafle, and a 
 delightful fmell : Greatefl part, if not all of it, is robbed of much of its better 
 parts before it is brought to us. Its elfential Oil is extremely pungent and 
 fiery, but in fmall quantity, fixteen ounces of the very befl Cinnamon fcarcely 
 yielding two fcruples and a half. The diftilled water appears milky, and re- 
 tains in it greatefl part of the Oil, which on long Handing it depofites to the 
 bottom, and then becomes clear : Oftentimes, though feveral pounds of Cin- 
 namon be committed to diftiilation, we fhall fcarcely be able to feparate any 
 Oil till the water has been kept for fome months. Mr. Stoll of Leipfick, pre- 
 tends to have a method of collecting all the Oil from the water in a very little 
 time i how juflly I cannot determine : If this fhould be found practicable, it 
 
 would 
 
Plants and their Parts. 403 
 
 would be a very ufeful difcovery, provided the Oil received no injury. The Cinnamon. 
 Dutch, who are mailers of the Spice Inlands, are the only perfons who prepare v— 
 the Oil of Cinnamon in quantity ; but it never comes from their hands unadul- 
 terated : We feldom meet with Oil of Cinnamon that holds lefs than half its 
 weight either of exoreiTed Oil or of Spirit of Wine. 
 
 The Oil of this fpice does not arife in diftillation with re&ified fpirit : On 
 diftiliing pure fpirit from Cinnamon, it received no fenfible impregnation ; on 
 drawing it over repeatedly from frefh parcels of the Spice, it fmelt and tailed a 
 little, but very weakly. An extradl made by fpirit contains the whole of the 
 talle and flavour of the Cinnamon : The watery extradl has nothing valuable. 
 
 Sixteen ounces yield two or more of fpirituous extract, and about one and a 
 half of watery. 
 
 CAS I A LIGNE A agrees with Cinnamon in its fmell, talle, and che- 
 mical compofition, and is the bark of a tree of the fame kind. It differs how- 
 ever remarkably in the proportion of its principles, containing much lefs Oil, 
 and a vallly larger quantity of mucilaginous matter. 
 
 XVIII. 
 
 CaSI A 
 Lignea. 
 
 THE Nutmeg tree, which grows moll plentifully in the ifland Banda, is XIX. 
 ranked by fome among the nuciferous, and by others among the pruniferousNuTMEC 
 
 trees ; the fruit being a nut, with a confiderable quantity of foit flelhy matter on i_ v 
 
 the outfide. Betwixt this pulpy lubllance and the fhell, lies a purpliflh-red 
 membrane, and within the fhell is inclofed a kernel of a fomewhat oval figure : 
 
 The firll is our Mace, the other Nutmeg. It is faid that the pulp has nothing 
 of the flavour of the Mace or Nutmeg, and is unfit for eating ; that the leaves 
 of the tree fmell ftrongly of Nutmegs, but that the flowers have little fmell. 
 
 The candied Nutmegs brought from abroad are a preparation of the entire 
 fruit, gathered unripe. 
 
 Nutmegs are cured in the Indies by throwing a quantity of Quick-lime upon 
 them in large tubs, filling up the veflels with water, and after maceration for 
 fome hours, rinling and drying the JVutmegs, which are then packed up for 
 exportation in calks fumigated with Sulphur: The fine powder which we fee in 
 the cracks and wrinkles of the Nutmeg is the remains of the Lime. This me- 
 thod of preparation, though apparently prejudicial, is faid to be found necef- 
 fary, for dellroying infeCts or preventing their production : This lall effeCt 
 however, it does not conftantly produce, for it is no uncommon thing to find 
 wormeaten Nutmegs. The Nutmegs of only one kind of tree are ufually 
 brought into Europe, though differing not only in fixe but in figure : Some 
 
 of the nuts contain two kernels, which in this cafe are flatted on one fide, and 
 called Royal Nutmegs. 
 
 Some prefer thole which difcover internally the greatelh quantity of white 
 variegations, but thofe which have the leafl are really the bell : It is in the red- 
 difh- brown matter, and not in the white, that the Oil and aromatic virtue re- 
 fide, the white having fcarcely any talle or fmell. It is only this inactive white 
 part that worms prey upon; and hence a Nutmeg is not much the worfe for 
 being wormeaten. It is amufing to examine a wormeaten Nutmeg, that has 
 had abundance of white veins : It looks a curious little labyrinth. 
 
 F f f 2 
 
 This 
 
4°4 
 
 Nutmeg. 
 
 Plants and their Parts. 
 
 This fruit contains two kinds of Oil, a grofs febaceous, and a volatile eflerr- 
 tial fluid one, in which lafb the tafte and fmell of the Nutmegs wholly refide. 
 The effential Oil appears alfo to be of two kinds, one light and fubtile, fo as 
 to fwim upon water, and arife in diftillation along with re&ified Spirit of 
 Wine •, the other groflfer and more ponderous, fo as to fink in water, arife dif- 
 ficultly in diftillation with water itfelf, and not at all with fpirit. 
 
 From fixteen ounces of Nutmegs I obtained half an ounce of eflfential Oil, 
 and from four and a half to five ounces of infipid febaceous Oil : This laft re- 
 mains behind after the diftillation of the other, and in part fwims like tallow 
 upon the furface of the water : The decoftion infpiflfated leaves a mere mucila- 
 ginous mafs, of no remarkable tafte or fmell. Rectified Spirit of Wine dif- 
 folves all the eflential Oil and a part of the expreflible:, and on being again ab- 
 ftrafted or evaporated, leaves in theextradl almoft all that it had taken up from 
 the fpice. 
 
 Four ounces of Nutmegs yielded with fpirit one ounce of oily extract, and 
 afterwards with water half an ounce and two fcruples of a gummy one, toge- 
 ther with five drams and one fcruple of expreflible Oil as infipid and inodorous 
 as the Gum. The fame quantity treated firft with water, gave ten drams of 
 gummy extract, with two fcruples and a half of grofs Oil which arofe to the 
 furface during the abftradtion of the liquor, and half a fcruple of eflential Oil 
 which funk to the bottom of the ^iftilled water : The remainder, treated with 
 fpirit, gave five drams more of grofs Oil, and two drams of an undtuous oily 
 extrad. The earthy matter amounted in both cafes to two ounces, or half the 
 original weight of the Nutmegs. On committing four ounces of Nutmegs, 
 pounded and warmed, to a warm prefs, I obtained nine drams of Oil : From 
 the refiduum were gained an ounce of gummy extrad, a pretty ftrong tailed 
 water, four fcruples of oily extrad with fpirit, and a dram of infipid Oil : The 
 earthy matter weighed here but eleven drams. 
 
 The grofs Oil of Nutmegs brings forth with it, in expreffion, a confiderable 
 portion of the eflential Oil, and hence is impregnated with the flavour of the 
 Spice. This Oil, or rather febaceous matter (for it is quite confiftent) is pre- 
 pared in quantity in the Eaft-Indies, and brought over fometimes in cakes, but 
 chiefly in fquare mafies like Sope, of a reddilh-yellow colour, refembling that 
 of Mace : It is vulgarly called Oil of Mace. Sixteen ounces of this concrete 
 contain five drams and a half of the eflential Oil of the Nutmeg, which totally 
 finks in water, and of which no part arifes in diftillation with Spirit of Wine^ 
 the more fubtile Oil having probably been diflipated in heating or roafting the 
 Nutmegs previoufly to the expreffion. The fluid expreflible Oil in the above 
 quantity amounts to fix ounces two drams and a half j and the folid febaceous 
 fubftance, which gives confidence to the two foregoing, to nine ounces and a 
 half. This laft, when feparated from the others, is perfedly infipid and ino- 
 dorous, and of a chalky whitenefs ; hence it is an excellent balls for odorifer- 
 ous balfams : We may impregnate it with any flavour by the addition of fuit- 
 able eflential Oils, and tinge it of any colour by coloured powders : It melcs 
 in a gentle heat like Tallow. 
 
 MACE 
 
Plants and their Parts. 
 
 4 C 5 
 
 XX. 
 
 Mace. 
 
 MACE, one of the exterior coverings of the Nutmeg, is at firft of a pur- 
 plifh- red colour, which changes, before it arrives among us, to an orange yel- 
 low, and by long keeping grows paler and paler. Mace is a warm aromatic, 
 like the Nutmeg, accompanied with a degree of bitterifhnefs ; and like that 
 Spice alfo contains both an effential and expreffible Oil. 
 
 Sixteen ounces of Mace yielded with rectified fpirit four ounces and a half 
 of extrad, which retained fome of the expreffible and the more ponderous part 
 of the effiential Oil, the lighter arifing towards the end of the infpiffation, and 
 impregnating the diftilled lpirit : From the refiduum were obtained two ounces 
 and a half of gummy extract, eight ounces and fix drams remaining undifiblved. 
 
 The fame quantity, treated with water firft, gave four ounces of gummy ex- 
 trad, with five drams of effential Oil, which arofe during the infpiffation, and 
 funk to the bottom of the diftilled water : The refiduum gave with redified fpi- 
 rit three ounces of an oily extrad, eight ounces and a half remaining undif- 
 folved. The watery extrad has an unpleafant fomewhat faline tafte, which 
 that of Nutmegs has nothing of. On expreffion, Mace yields an Oil lefs con- 
 fiftent than that of Nutmegs, and which is ufually brought from the Eaft- 
 Indiesin glafs or porcelane veffels. 
 
 CLASS VI. 
 
 Vegetables whofe qualities depend partly upon an effential Oil, and partly 
 
 on a gummy -ref nous matter . 
 
 T H E fubftances of this clafs agree with thofe of the foregoing in containing Oily-gum. 
 
 an effential Oil, fometimes in large and fometimes in fmall quantity. Resinous. 
 They differ in containing other adive matters joined to the Oil. There, the ; 
 
 Oil and diftilled water poffefs the whole of the fpecific tafte and fmell of the 
 fubjed: Here, they poffefs but a part, thedecodion left after the diftillation, 
 retaining aconfiderable fhare of that peculiar tafte by which the original vege- 
 table was diftinguifhed. Thus the Carline-thiftle, Camomile, Wormwood, 
 Orange-peel, &c. leave all their bitternefs in the decodion, whilft all their 
 fmell and flavour diftil : And fome of the fpices, as Cloves and Pepper, leave 
 in like manner greateft part of their pungency behind. 
 
 THE Carline-thistle [Carlina acaulos magno flore albo C. B.) is a very I. 
 prickly fort of Thiftle, without any ftalk, growing in mountainous countries, Carline. 
 particularly in the mountains of Switzerland. The roots are brought to us 
 tied in bundles, chiefly from Thuringia. They are fix or eight inches in 
 length, about the thicknefs of the little finger, ol a brown colour on the out- 
 fide and whitifh within ; of a ftrong not agreeable fmell, and a bitter pungent 
 tafte. They are fometimes ufed as diaphoretics and alexipharmacs, but chiefly 
 in the diforders of cattle. 
 
 Sixteen ounces of this root yield about two-fcruples and a half of effential 
 Oil : This contains the fmell and all the fpecific tafte of the root, as the Refin 
 does its bitternefs. It is difficult to obtain the Oil and the Refin perfedly pure 
 
 from. 
 
4oS P it a n t s and their Parts. 
 
 Carline, from one another. A tindure made in redified fpirit, leaves, on being in- 
 fpiffated to an extrad, aimed all the Oil, along with the Refin, and a portion 
 of the gummy matter, the diddled fpirit having fcarcely any fmell or take. 
 And on the other hand, in diddling the Oil with water, fome of the more fub r 
 tile parts of the Refin condantly arife with it, rendering the Oil thick and ropy, 
 or di (poled to become fo upon danding for a little time, and fo ponderous as to 
 link in water : On redifyingthe Oil, or diddling it a fecond time with a gentle 
 heat, itarifes fluid and thin, and floats on the furface of the water, leaving be- 
 hind a confiderable quantity of grofs refinous matter. 
 
 Two ounces of the root, cut in frnall pieces, yielded with redified fpirit two 
 drams thirty-eight grains of refinous extrad, diffidently ftrong both in fmell 
 and tafte, and poffeffing nearly all the adive parts of the Carline : From the re- 
 fiduum were obtained, by water, fix drams two fcruples of mucilaginous ex- 
 trad, in tafle (lightly bitterifh and fomewhat faline. On inverting the order 
 of applying the refpedive mendrua, the watery extrad amounted to an ounce 
 and half a dram, and the fpirituous only to forty-five grains. The watery ex- 
 trad made at fird was much dronger than that made after the adion of fpirit, 
 but far weaker than that made by fpirit at fird. 
 
 II. T H E feeds of Fennel-flower', Nigella, Melanthium , Gilh , ( Nigella flore 
 
 Nigella. minor e fimplici candido C. B .) are of an irregularly angular figure, a black colour 
 v,— -v— « on the outfide and greyiffi within, of a pungent aromatic and fomewhat oily 
 fmell and tade. We often find among them fome yellow ones, which are fup- 
 pofed to be unripe. 
 
 Thefe feeds contain only afmall quantity of volatile effential Oil, but a larger 
 of a grofs expreffible one, feparable not only by adual expreffion, but by ex- 
 traction with Spirit of Wine, the Oil diffolving in the fpirit along with the re- 
 finous matter, and afterwards parting from it in the evaporation : A grofs Oil 
 may be colleded in this procefs, whether the gummy matter has been previ- 
 oufly feparated by water or not, with only this difference, that the Oil ob- 
 tained after the adion of water becomes fooner rancid than the other. 
 
 Two ounces of the feeds yielded with redified fpirit three drams of extrad, 
 and afterwards with water three fcruples and a half: Water applied at fird ex- 
 traded juft as much as fpirit did ; but fpirit after water took up lefs by a fcruple 
 and a half than water after fpirit. The quantity of Oil which feparated in the 
 fpirituous extradion, was four fcruples. The diddled fpirit fmek and faded 
 confiderably of the feeds : The fpirituous extrad was neverthelefs dronger than 
 the watery -— — — Thefe feeds are recommended in catarrhs, vertigos, quar- 
 tans, (Ac. and as an errhine. 
 
 Up B I RT H W O RT, Ariftolochia , fo called from the medical virtues afcribed 
 Birthwort. to it, is a . plant with an irregular, tubulous, monopetalous flower. Three 
 forts are mentioned by pharmaceutic writers : Ariftolochia rotunda flore ex pur- 
 pura nigro C. B round- rooted Birthwort ; Ariftolochia longa veraC.B. long- 
 rooted Birthwort ; and Ariftolochia clematitis redla C. B. (lender or creeping- 
 rooted Birthwort. The name Birthwort is applied alfo to two plants of another 
 genus, the bulbous rooted Fumitories : The Ariftolochia rotunda vulgaris or 
 
 cava , 
 
Plants and their Parts. 
 
 407 
 
 cava , is that called by Cafpar Bauhine Fumaria bulb of a radice cava , major, flore Birthwort, 
 rubro dilu fibre : The Arifiolochia fabacea is the Pitman a bulbofa radice non cava 
 minor of the fame author. Of ail the forts, the root is the part principally 
 made ufe of: Thofeof the round are pretty thick, unequal, full of round pro- 
 tuberances, fometimes fhaped like a kidney, externally brown, internally yel- 
 low like Boxwood : Thofe of the long are aifo brown on the outfide and yellow 
 within, near a foot in length, from two to three or four fingers in thicknefs, 
 and full of wrinkles : Thofe of the creeping-rooted are the longed: and flendereft, 
 and of the darkeft brown colour on the outfide-, the largeft are fcarcefo thick 
 as the little finger, and the greater number fcarce half fo thick : The roots of 
 
 the Rotunda vulgaris are about the fize of Walnuts, pointed in the middle, 
 brown without, hollow within : Thofe of the Fabacea are no larger than Fil- 
 berds, commonly flatted, externally yellow, internally mealy and white. 
 
 In tafle they are all bitter and aftringent, but in different degrees : TheFV- 
 bacea is much the weakefl. and the flender rooted fort the ftrongeft, Hence 
 they differ alfoin medicinal virtue: Simon Paulli obferves particularly of the 
 
 long-rooted, that a decodion of it in the diftilled water of Veronica is of ex- 
 cellent fervice againft ulcerations on the fhinbone, and fays he has received the 
 thanks of many furgeons for the communication of this medicine. 
 
 With regard to their chemical analyfis, they all give out more to water than 
 to fpirit : An ounce yields with fpirit fomewhat more than a dram ofrefinous 
 extrad, whilft the fame quantity, treated with water, gives upwards of two 
 drams of a gummy one. The fpirituous extrad taftes ftrongly of the root, but 
 the watery has very little tafte. In diftillation, redified fpirit brings over no- 
 thing from the root; the diflilled water has a difagreeable kind of fmell, diffe- 
 rent from that of the Birthwort itfelf. 
 
 The leaves of one of the Birthworts, namely of the long fort, are fometimes 
 alfo employed medicinally. Thefe are of the fhape of a heart, full of veins, 
 both longitudinal and tranfverfe, and of an extremely ftrong fmell. They 
 give out conflderably more than the roots do to redified fpirit, and fomewhat 
 more to water : From an ounce were obtained two drams of fpirituous, and 
 from another ounce two and a half of watery extrad. 
 
 It has been affirmed, that the fixed alcaline Salt obtained from Birthwort by 
 burning, is of a peculiar kind ; that it does not, like other fixed alcalies, throw 
 down a yellow Precipitate from folution of Mercury fublimate. Tournefort 
 mentions this particularity of the Clematitis or flender-rooted fort, and fays he 
 took it from the experiments upon the regiflers of the French Academy. I 
 have tried the experiment, and found that the fmalleft portion of the Salt of 
 Birthwort, added to a folution of Sublimate, throws down a yellow Precipitate 
 equally with the alcaline Salts of other plants. 
 
 T H E leaves of common Wormwood {Abfinthium vulgare majusj. B.) are Wormwood, 
 intenfely bitter, and have a ftrong fmell, fomewhat of the aromatic kind, but 
 ungrateful. They yield in diftillation a confiderable quantity of eftential Oil, 
 of a dark greeniffi colour, pofleffing the whole of their fmell, the bitter matter 
 remaining in the extrad. 
 
 THE 
 
4-0 8 
 
 Plants and their Part s. 
 
 V. THE flowers of the common Camomile {fhamamelum vulgar e , leucan - 
 Camomile, themum diofcoridis C. B.) contain alfo a bitter fubftance joined with an eflential 
 ‘ T ~T ' Oil of a peculiar ftrong flavour. 
 
 The quantity of Oil is very fmail, a whole pound of the flowers yielding 
 fcarcely above a fcruple : It refldes, not in the white petala, nor in the yellow 
 difk, but folely in the cup of the flower. This Oil appears of a beautiful deep 
 blue colour ; not as lome have fuppofed from its diffolving a part of the Cop- 
 per veflel in which thefe kinds of diftillations are ufually performed, for it 
 proves of the fame colour when drawn in glafs ones : By age, its fine colour 
 gradually decays, and changes at laft to a brownifh or a greenifh yellow. 
 Hoffmann reports that the genuine Oil of Camomile will not continue blue 
 above a year, and that fuch as holds its tindture longer than that time has re- 
 ceived it from art: But on trial, the genuine as well as the counterfeit Oil, if 
 kept in bottles quite full and clofely fecured from the air, are found to retain 
 their colour for two or three years or more, and both of them to lofe it in a 
 fhort time if there is any vacuity in the veffel, or if the air is admitted : The 
 blue colour of the counterfeit is deftroyed by air, and changed to a green, even 
 fooner than that of the genuine. 
 
 An ounce of the dry flowers yielded with Spirit of Wine three drams, and 
 afterwards with Water two drams of extradt : Water applied at firft extradhed, 
 from the fame quantity four drams, and Spirit afterwards one dram: The in- 
 difloluble refiduum weighed in both cafes three drams. 
 
 Simon Paulli obferves that thefe flowers contain a manifeft faline fubftance ; 
 that when digefted and boiled in Wine, and two or three frelh parcels boiled 
 in the fame liquor, the Wine prefled out from them taftes at length notably 
 faline. I repeated this experiment, and found the liquor to be of a truly faline 
 tafte, approaching in fome degree to that of common Salt. I therefore tried 
 it with a folution of Silver and of Quickfilver : It occafioned a precipitation in 
 both, but the precipitate of the Silver was not a Luna cornea , nor that of the 
 Mercury flmilar to Corrofive Sublimate, which they would have been if the 
 Salt had been of the marine kind. It is probable, that the Salt proceeded in 
 good meafure from the Wine, though the tafte of the decodtion was different 
 from that of boiled Wine by itlelf. 
 
 Camomile flowess are fuppofed to have an antifpafmodic and mild anodyne 
 virtue, depending on their Oil : Their bitter matter is flmilar in quality to that 
 of Wormwood, Gentian, Centaury, dfV. The oil, as already obferved, is 
 lodged in the cup j the bitternefs prevails chiefly in the yellow difk of the flower. 
 Roman. The flowers of the Roman Camomile Chamamelum nobile five leucanthemum 
 
 odoratius C. B.) have a ftronger and more agreeable fmell than thofe of the 
 common. They yield a larger quantity of eflential Oil, but the Oil has no- 
 thing of the fine blue colour of the other. The quantity of gummy and reft- 
 nous matter is almoft exadtly the fame in both. 
 
 VI. 
 
 Orange and THE outer yellow rind of the Peels of Oranges and Lemons contains 
 Lem. Peel, a bitterifh matter, accompanied with a very fragrant aromatic Oil, fo volatile 
 as t0 ar jf e j n diftillation with re&ified Spirit as well as with Water. The Oil 
 5 drawn 
 
Plants and their P arts. 409 
 
 drawn with Spirit is the mod elegant of the two, and that from the frefh Peels Orange and 
 more fo than from the dry: But none of the Oils prepared by diftillation are U:M ~ Peel ; 
 equal to that extracted by pundture or fcarification (fee page 271.) 
 
 All effential Oils are imbibed readily by pure dry Sugar, and unite with it 
 into a compound foluble in Water : In this form, called EUoJaccharum , they 
 are often made ufe of in medicine : An elaeofaccharum of Orange and Lemon- 
 peel may be obtained, by rubbing the fruit upon a lump of Sugar till ail the 
 yellow part is abraded, and then fcraping off fo much of the Sugar as appears 
 impregnated with the Oil. 
 
 THE flowers and tops of the common purplifli- flowered Milfoil or yar- yjj 
 row ( Millefolium vulgar e ■pur pur eum minus C. B.) afford a beautiful blue Oil flmi- Milfoil . 7 
 
 lar to that of Camomile. The white flowered fort yields an Oil of the fame 
 
 flavour with the other, bup which has nothing of its colour. 
 
 Thefe flowers have a not difagreeable aromatic fmell, and a roughiftr, bit- 
 terifh, fomewhat pungent tafte : The bitternefs and aftringency remain in the 
 extracts, whether made by Spirit or by Water. An ounce of Milfoil tops 
 yielded with Water three drams and a fcrupie, and afterwards with Spirit only 
 fix grains : Spirit applied at firft extracted, from the fame quantity, two drams 
 and a half, and Water afterwards one dram thirty-feven grains : The lndiffo- 
 iuble reflduum weighed in the firft cafe four drams thirty-feven grains, in the 
 latter forty grains lefs— — This plant is looked upon as an excellent corrobo- 
 rant and antifpafmodic. 
 
 THERE is another plant which affords a blue Oil that ariles not only yjjj 
 with Water, but with highly rectified Spirit of Wine; the Pimpinella nigra orp IMP]NELLA 
 Black Burnet-Saxifr age. This plant has not hitherto been defcribed by the Nigra. 
 
 botanifts : It appears to be a fpecies of Tragofelinutn, and may not improperly v * 
 
 be called Pr ago/eli mint majus radice nigra : Perhaps it is the Pragofdinum alterum 
 majus of Tournefort, Pimpinella Saxifraga major altera of Cafpar Bauhine, Saxi- 
 fragia hircina minor foliis Janguiforba of John Bauhine, 1 Tragofelinum minus , Pim- 
 pinella minor of Tabermemontanus. Its leaves are fomewhat different from 
 thofe of the Pimpinella alba (page 341.) but the principal difference is in the 
 roots, which inftead of being of a white colour throughout, are black on the 
 outflde, and variegated internally with bluifh veins. As the French chemiffs 
 called in queftion the blue Oil of this root, I fent them a fpecimen of the Oil 
 drawn by myfelf, of its blue diflilled fpirit, and of the entire plant with its 
 root, flowers and feeds ; with a quantity of roots for repeating the experi- 
 ments, and a quantity of frefh feeds for propagating the plant. The Spirit 
 ariles blue only about the middle of the diftillation, the firft and the laft run- 
 nings being colourlefs : If thefe are kept apart, the Spirit proves of a deep 
 blue colour ; if the whole is mixed together, very pale. The diftilled Water 
 has no bluenefs. The Oil, like thofe of Camomile and Milfoil, foon lofes its 
 blue colour in the air, changes to a green, and at laft to a yellow. 
 
 This black Pimpinella-root has the fame fmell and tafte with the white fort 
 formerly examined : It yields alfo the fame principles on extraction with Wa- 
 ter and with Spirit, but in fomewhat different proportions. From two ounces 
 
 G g g were 
 
4*0 
 
 Plants and their Parts. 
 
 Pimpinella were obtained by rectified Spirit three drams of a refinous extrad, more unetu- 
 Nigra. ^ ous or 0 jjy t han that of the white Pimpinella, and afterwards by Water three 
 c l ram s of a gummy extrad : Water applied at firft extracted five drams, 
 and Spirit afterwards only one : The refiduum, in both cafes, weighed ten 
 drams. 
 
 IX. CALAMUS AROMATICUS, or Acorus Verus , is the root of a kind 
 Calamus of flag growing in marfhy places in fome parts of Europe : It is pretty long, 
 Aromat . full of joints, of a whitifh, reddiih, and partly of a greenifh colour on the out- 
 v— fide, white and fpongy within, eafy to break, of a flrong aromatic fmell, and 
 a warm pungent tafte. In firm grounds, it fpreads into many flender firings, 
 which in mere watery ones it does not. 
 
 The diftinguifhing tafte and grateful flavour of this root refide wholly in 
 the effential OiS, the decodion remaining after the distillation of the Oil hav- 
 ing a naufeous tafte not at all like that of the Calamus : From fixteen ounces 
 of the dry root little more than two fcruples of Oil are obtained : From the 
 freih roots we can fcarcely colled any, the Oil remaining all diflfolved in the 
 diftilied Water. Hermann reports that the Oil and Water of Calamus Aro- 
 inaticus are highly ungrateful, but they are quite the reverfe : Nor do the old 
 decayed roots, which Wedel fupeds Hermann’s Oil and Water to have been 
 drawn from, give any thing difagreeable in diftillation. 
 
 Highly redified Spirit elevates little or nothing of this Oil : Hence a fpiri- 
 tuous extrad made from the root fmells confiderably, and taftes ftrongly, of 
 the Calamus. Two ounces yielded with Spirit fix drams and half a fcruple, 
 and afterwards with Water three drams ten grains of extrad: Water applied 
 at firft extraded, from the fame quantity, feven drams thirty-five grains ; and 
 Spirit afterwards forty three grains. 
 
 X. CYPERUS ( Cyperus rotundus Or lent alls major C. B.) is the root of a plant 
 Cyperus. approaching to the flag kind, brought from the eaftern countries : It is nearly 
 of the fhape of an Olive, of a reddifh brown colour on the outfide, of a red- 
 difh white within, compad, pretty ponderous, of an agreeable aromatic fmell 
 and tafte, with a flight bitternefs and aftringency. The French, inftead of 
 this, ule commonly a root of their own growth {Cyperus rotundus vulgaris C. B.) 
 which does not greatly differ from the Oriental : This fort is found alfo in 
 Switzerland, Italy, and fome other parts of Europe. 
 
 The ancients employed Cyperus as a Spice : At prefent it is fometimes ufed 
 medicinally, but chiefly as an ingredient in hair powders, fweet-fcented pow- 
 ders for clothes, and other like purpofes. The quantity of Oil it contains is 
 very fmall : From an ounce or two of the root we can fcarcely colled any. 
 Redified Spirit of Wine elevates nothing of this Oil, but diftils flavourlefs as 
 it was employed : Hence the fpirituous extrad retains the flavour as well as the 
 tafte of the root, though the watery extrad is rather ftronger in tafte. 
 
 Two ounces of the root yielded with Spirit three drams of extrad, and 
 afterwards with Water three drams and a fcruple •, The fame quantity, treated 
 firft with Water, gave fix drams,, and afterwards with Spirit half a dram t 
 
 The- 
 
P l a n t s and their Parts. 41 1 
 
 The indiiloluble earthy matter weighed in the firft cafe nine drams two fcruples, Cyperus. 
 and in the latter nine drams and a half. -v-"— ^ 
 
 Z EDO ARY is the root of a plant faid to be of the Ginger kind, grow- xi. 
 ing in different parts of the Eaft Indies, and brought to us chiefly from Ben- 2edoar y„ 
 gal. There are two forts of it, a long and a round: The firft, which is ac- 
 counted the beft, is about the fize of the little finger, fometimes larger and 
 fometimes fmaller, of a whitifh and vellowifh grey colour, darker on the 
 outfide and lighter within, compadt and firm, of an aromatic fmell and tafte 
 fomewhat approaching to t'nofe of Rofemary and Camphor, accompanied with 
 a degree of bitternels. 
 
 Sixteen ounces of this root yield about a dram, feldom more, of efiential 
 Oil, poffefiing the whole of its fmell and aromatic flavour ; the bitternefs re- 
 maining in the decodtion. The Oil is very ponderous, finks in Water, and 
 difficultly arifes in diftillation : The more fubtile part which comes over firft 
 is almoft colourlefs ; the reft is partly greenifh, and partly blackiffi. Redlified 
 Spirit elevates a little of its finer parts, but does not receive near fo ftrong an 
 impregnation as Water does-, and hence the fpirituous extradl retains much of 
 the peculiar flavour of the Zedoary, which in the watery is wholly loft. 
 
 Sixteen ounces yielded of watery extradl five ounces five drams and one 
 fcruple; after which, Spirit extradled about two drams two fcruples of an al- 
 moft infipid Refin. The fame quantity, treated firft with Spirit, gave an 
 ounce and a half, and afterwards with Water full five ounces : This laft ex- 
 tradl tailed much bitterer than that obtained by applying Water at firft. 
 
 GINGER is the produce both of the Eaft and the Weft Indies. Two forts 
 of this root are brought to us, one internally white, the other brown : Whe- r 
 ther they are the roots of different fpecies of the Ginger-plant, or of one fpe- , lh 
 cies taken up at different ages or in different feafons, is not certainly known. 
 
 This pungent aromatic is of common ufe as a Spice, and is obierved not to 
 heat the conftitution near fo.much as might be expedted from its ftrong biting 
 ■tafte. Its pungency refides not in its volatile but in its fixed parts : The eflfen- 
 tial Oil contains the fmell and diftinguifhing flavour of the Ginger, but all the 
 pungency is left behind in the ftill. 
 
 From fixteen ounces of the common brown Ginger may be obtained a dram lv , ( 
 or a little more of Oil. The fame quantity yielded, with redtified Spirit, an 
 ounce and two fcruples of refinous extradl, containing all the hot biting mat- 
 ter of the root : From the refiduum. Water extradted a ftrong mucilage, which 
 had little or no tafte, was difficultly reduced to drynefs, and weighed, when 
 exflccated, five drams and a half. , Sixteen ounces, treated firft with Water, 
 gave four ounces of extradl confiderably pungent, a portion of the refinous 
 matter being taken up by the Water along with the gummy : From the refi- 
 duum, Spirit extradled five fcruples four grains of a very pungent Refin. The 
 indiiloluble earthy matter amounts to near three fourths of the root, viz. 
 eleven ounces fix drams and fixteen grains. Redlified Spirit elevates in diilil- 
 lation fome of the more fubtile parts of the Oil, fo as to tafte a little of the 
 Ginger, though not confiderably. 
 
 G g g 2 
 
 The 
 
412 
 
 Plants and their Parts. 
 
 white. 
 
 Ginglr. The white Ginger contains more foluble matter than the brown. From fix- 
 J teen ounces of this fort were gained five ounces five drams and a fcruple of 
 watery, and afterwards three drams twelve grains of fpirituous extract. Spirit 
 applied at firft extraded one ounce and three drams wanting a few grains ; 
 and Water applied afterwards took up four ounces and a half; fo that the in- 
 diffoluble part does not amount quite to ten ounces on fixteen. The quantity 
 of effential Oii is nearly the fame as in the brown fort. 
 
 XIII. THE greater Galangal, an Eaft Indian knotty root with feveral circles 
 Galangal. on the f ur face, of a reddifh brown colour on the outfide and a yellowifh white 
 lar^ei^ within, greatly refembles Ginger in its fmell, tafte, and chemical compo- 
 fition ; but as Ginger is the moft grateful of the two, the Galangal is fcarcely 
 ever ufed. 
 
 imaller. The fmaller Galangal, which is knotty and marked with circular ftrise like 
 
 the other, commonly about the fize of the little finger, and of a brown colour 
 both externally and internally, is in fmell fironger and more agreeable than 
 the large, and in tafte more pungent and hot like Pepper. It contains but a 
 fmall proportion of Oil : Sixteen ounces afforded fcarcely two fcruples ; though 
 probably if confiderable quantities were diftilled at once, and the diftilled Wa- 
 ter of one operation employed inftead of frefh Water in the next, the yield 
 upon the pound would be greater. The Oil is Jefs agreeable in fmell than the 
 Galangal itfelf, and wants its pungency, which of confequence remains in the 
 extradf. Very little of this Oil arifes with redtified Spirit: The Spirit diftilled 
 even from a large quantity of the root, has fcarcely any tafte or fmell. With 
 regard to the extracts, the watery is rather more pungent than the fpirituous ; 
 but the former have nothing of the peculiar flavour of the Galangal, greateft 
 part of which is retained in the latter. Sixteen ounces yielded with Water fix 
 ounces, and afterwards with Spirit four drams two fcruples : Spirit applied at 
 firft extracted an ounce and a half from fixteen, and Water extracted after- 
 wards five ounces. 
 
 XIV. T HE Clove tree, Cary ophy Hus aromaticus frutlu oblongo C. B. is a native of 
 Cloves, the Molucca iflands, and has not been found to thrive fo well in any other 
 v— — v— part even of the Eaft-Indies. It is about the fize of a large cherry-tree : The 
 leaves are fomewhat like thole of the bay, and the wood like boxwood. The 
 Clove-fpice has been fuppofed by fome to be the flowers, by others the fruit 
 of the tree, but it does not appear to be either of thefe : It is ftriclly the cup 
 of the unexpanded flower, as Dr. Schrceck firft obferved in the Ephemerides 
 Nature Curio forum * . 
 
 The manner of fructification of the Clove-tree may be underftood from that 
 of the common Dog-rofe. The Dog-rofe puts forth, at the ends of the 
 branches, rounchfh buttons, which open at the extremity into feveral pointed 
 iegments, furrounding a little knob, which gradually unfolding becomes the 
 flower : When this falls, the button, which ferved for its cup, becomes the 
 fruit. The Clove-tree, inftead of a round, has an oblong cup like a nail, 
 four points at the end turning outwards and forming the head : This is at 
 firft green , when the rudiments of the flower begin to fhew themfelves in 
 
 the 
 
Plants and their Parts. 413 
 
 the middle of the points, it turns reddifh or brownilh, and in this ftate is theC loves. 
 Clove- fpice. c-— v— — ’ 
 
 Some report that the Cloves fall off of themfelves, others that they are 
 fhaken, and others that they are beaten off. There is little probability of their 
 being procured by any of thefe means : Thefe cups, as thole of other flowers, 
 adhere firmly to the plant : by beating, they would be bruited or broken, or 
 at leaft lofe the flower buds at the end, which eafily come off, and which are 
 ftudioufly preferved. We cannot fuppofe them gathered any otherwife than by 
 hand. Nor is it probable, that they are dried in fmoke, or dipt in Sea- water 
 before the drying ; for both thefe would be injurious to, them. 
 
 Cloves, as brought to us, are externally of a reddilh brown colour, inter- 
 nally of a paler yellowilh, of a ftrong aromatic fmell, and a very hot pungent 
 tafte : They are eafily broke by the fingers, which they impregnate at the 
 fame time with their fmell : On piercing them with a needle, a little liquid 
 matter like Oil oozes out-, a mark of the goodnefs of the Cloves. The Dutch, 
 who are the mailers of the Clove iflands, diflil large quantities of the Oil of 
 Cloves upon the fpot, and fupply the other parts of the world with the eifen- 
 tial Oil as well as with the Spice in fubftance : The Cloves that have been 
 thus robbed of their Oil they mingle with frefh Cloves, from which they ac- 
 quire a confiderable fhare of fmell. A light brown colour gives fufpicion of 
 this abufe, and if we examine thefe pale ones by themfelves, we fhall eafily 
 find whether they retain or have loft their native Oil. 
 
 The Dutch Oil of Cloves is extremely hot and fiery, and of a reddifh brown 
 colour, and thefe are in general looked upon as charadteriftics of its genuine- 
 nefs. This Oil, however, in its pure and perfect Hate, is very far from hav- 
 ing either of thefe qualities. When newly diftilled it is colourlefs; by long 
 keeping, in glades not quite full or not fufficiently fecured from the air, it be- 
 comes more and more yellow or brown. It fmells exceeding ftrongly of the 
 Cloves, but its tafte is quite mild in companion to that of the Dutch Oil. 
 
 The pungency of this Spice refides in the Refin, or rather in a combination 
 of the Refin with the Oil : The fpirituous extract is exceflively fiery : but if 
 this extract be freed from its Oil by diftillation with Water, the Oil that arifes 
 proves mild, and the remaining Refin infipid. The fhare of heat and pun- 
 gency which the Oil does retain, feems to proceed wholly from a portion of 
 the Refin elevated along with it we can free it fo far from refinous matter ' 
 that it fli all be equally foft and infipid upon the tongue with Oil of Almonds, 
 its fmell ftill continuing. 
 
 The Dutch Oil of Cloves is largely adulterated : From an ounce I have fe~ 
 parated no lefs than half an ounce of an infipid and inodorous expreffed Oil. 
 
 As this addition renders the genuine Oil ftill milder, they mu ft neceftarily 
 employ fome other to give it fierynefs; and this is probably the fpirituous ex- 
 tract, which I have found to communicate at once both the pungency and 
 high colour. 
 
 Where genuine Oil of Cloves is wanted, for medicinal or other ufesy we 
 muft diftil it ourfelves, and this we may do with eafe. I know of no herb, 
 root, bark, fruit or feed, that yields fo much : From fixteen ounces of Cloves 
 I obtained two ounces two drams : Hoffmann gained two drams more. It is 
 
 4 con- 
 
4*4 Plants and their Pa r t s. 
 
 Cloves, convenient to life a low head, to return the diftilled Water upon the remain- 
 L — v— .. L. ; ing Cloves, and to repeat the diftillation two or three times; this Oil being 
 very ponderous, fo as not readily to arife. It conftantly finks in Water, tho’ 
 Pomet and Valentine make it a mark of its goodnefs to fwim. Pure Spirit of 
 Wine elevates nothing of it, whether the Spirit is drawn over from the Oil 
 itfelf or from the Clove in fubftance. The deco< 5 tion remaining after the dif- 
 tillation of the Oil yields, on being infpiflfated, a naufeous fomewnat aflringent 
 extraft, amounting to fix drams and afcruplefrom two ounces of Cloves: The 
 fame quantity yields, of fpirituous extract, only about five drams. 
 
 Anto- THE fruit of the Clove-tree (called Antophyllus) is of an ova! figure, 
 phyllus. with an umbilicus or crown at the extremity, from the remains of the flower. 
 
 It confifts of a fkin or membrane, including a kernel about the hardnefs of a 
 Bay-berry. It is much weaker than Cloves both in fmell and tafte, though 
 fome have injudicioufly preferred it to them. The ablive matter of the Clove 
 or cup refules chiefly in its cortical part : As the Clove increafes, this matter 
 is partly altered or difflpated, and partly propelled more and more outwards, 
 till, in the fruit, all of it that remains is confined folely to the exterior fkin, 
 the kernel having nothing of the Clove flavour. 
 
 XV. AMO MUM is an exotic fruit, commonly ranked among the feeds. 
 Pimento. There have been different conjectures about the Amomum of the ancients, 
 L—*— and different lubftitutes propofed in the room of that unknown Spice. The 
 Amomum of the German (hops is an American berry, called by theEnglifli 
 Jamaica Pepper, Pimento, or All-fpice ; by fome Piper chiapa , tavafci , 
 cdoratum , Grana caryophylli , Bacca pant aromatics. 
 
 The Jamaica Pepper- tree is a native of the ifland whofe name it bears, 
 particularly of the hilly trads on the north-fide. It rifes to the height of 
 about thirty feet, covered with an extremely fmooth grey bark : It is full of 
 branches, clothed with dark fhining green leaves, pointed at both ends, of an 
 aromatic fmell when rubbed, like that of the common Bay-leaves : On the 
 extremities of the branches come forth clufters of flowers, each Handing on a 
 feparate pedicle, compofed of four pale green herbaceos petala, with feveral 
 ftamina in the middle : The berries have a crown on the top, compofed of 
 four little leaves ; at firft they are green ; when ripe, they are black, fmooth 
 and fhining, and larger than Juniper- berries : Internally they contain a moift, 
 green-coloured, pungent, aromatic pulp, and two hemifpherical feeds or ker- 
 nels, joined together by the flat fides, with a fkin between them. The berries 
 are gathered in their unripe Hate, and dried in the fun ; by which their green 
 colour is changed to a yellowifh, brownifh, and at length to a reddifh or rufty 
 brown, or a dark brown. 
 
 Such is the Pimento-tree as defcribed by Sir Hans Sloane in the Philofo- 
 phical tranfadions, No. 292, under the name of Myrtus arborea aromatica , 
 folds laurinis (aromatic Tree- myrtle, with Bay like leaves.) Plukenet and 
 Dale make the true Pimento the produce of a different Species. The former 
 diftinguifhes Sloane’s tree by the name of Caryopbyllus aromaticus Americans , 
 lauri acuminatis folds , fruciu orbicularis (American Clove-tree, with acumi- 
 nated 
 
Plants and their Part s. 4x4 
 
 nated leaves like thofe of the Bay, and a round fruit;) and the tree, which he Pimento. 
 propofes himfeif, by that of Caryophyllus aromaticus Americanus, fcliis & fruElibus e— 
 rotundis. dipyrene , feminibus fere orbiculatis plants^ (American Clove-tree, with 
 round leaves and fruit, and in each berry two roundifh flat feeds). In his Al- 
 raageftum he mentions a third fpecies, Caryophyllus aromaticus Americanus , folio LA 
 fruclu oblongo, polypyrene, acinis angulofis uvarum vinaceis fimilibus , (American 
 Clove- tree, with oblong leaves and fruit, angular feeds like thofe of grapes, 
 and more than two in one berry). But thele are probably rather varieties than 
 different fpecies, as Sir Hans, a very fkilfuf botanift, and who lived many years 
 on the fpot, refers them all to the tree which he defcribes. 
 
 Thus much is certain, that the berries of the feveral trees are ufed promifcu- 
 oufly. Among thofe brought to us, we may didinguifh not only different 
 fizes, from their age or degree of maturity, but differences in fhape, in the ap- 
 pearance of the crown or navel, and in the figure and number of the kernels. 
 
 Some are round, fome oval, fome Pear fliaped, and others flatted : In fome the 
 crown is flat, in others elevated : The feeds are in fome hemifpherical, in fome 
 angular, in others flat, approaching to a Kidney fhape: The number of feeds 
 is mod commonly two, fometimes three, four, or more ; rarely or never one. 
 
 Clufius indeed makes but one feed in each berry, but he was deceived by the 
 two joined together. I have obferved alfo another fort, not mentioned by 
 Sloane, Plukenet, or any other author I know of : Indead of the berries (land- 
 ing all on didinft pedicles, there are three, four, or more, upon one; and 
 thefe flatted in a Angular manner, with always a piece of the main flalk pro- 
 jedting beyond them. I have fometimes found among the berries fmall par- 
 ticles of Refin, in appearance refembling Myrrh, but differing from it in talle ; 
 adhering flrongly to the berry, from which it had probably been melted out 
 by the fun’s heat. 
 
 The feveral forts of thefe berries, however different in appearance, agree in 
 quality. They have a pleafant aromatic fmell and tafle, compofed as it were, 
 of thofe of Cloves, Nutmegs, Cinnamon, Pepper and juniper-berries : The 
 Clove flavour prevails above the reft. The bed are thole whole fmell and tafle 
 are the drongeft. They are ufed in large quantity in England, rather as a 
 common Spice than in medicine : They are preferred to mod other fpices, 
 as being of a milder nature, and lefs apt to heat the conditution. 
 
 With regard to the component parts of Jamaica Pepper, we find little or 
 nothing in books, except that Sloane has mentioned that an Oil may be di - 
 ddled from it. Upon a chemical examination it appeared to confid of (1.) An 
 indiffoluble earth, exceeding in quantity all the other principles taken toge- 
 ther, and amounting to five drams and afcruple upon an ounce. (2.) Gummy 
 or mucilaginous matter, which is the ingredient next in quantity. An ounce, 
 treated with water at fird, gave two drams and two grains of gummy extrafl ; 
 and another ounce, freed by rectified fpirit from all that that mendruum could 
 dilTolve, yielded dill with water five fcruples of Mucilage. (3.) A refinous fub- 
 dance in 1 'maller quantity. The refinous extradl obtained by applying rectified 
 fpirit at fird, amounted to only one dram and fix grains from an ounce : Aa 
 ounce, freed from its mucilaginous matter by codlion in water, yielded of 
 pure Re fin no more than one fcruple. (4.) An effential Oil, in dill fmaller 
 
 quantity s 
 
Plants and their Parts, 
 
 .quantity : Of this principle, an ounce contains fcarce half a dram, or one 
 fixteenth. 
 
 Upon examining the qualities of the feveral products, it appeared, ( i.) That 
 the Oil is the principal and the charadleriftic part, containing all the fmell and 
 the aromatic flavour, though not the pungency of the berry. As the prevail- 
 ing flavour of Pimento approaches to that of Cloves, the Oil alfo greatly re- 
 fembles the genuine Oil of that fpice : It has the fame kind of fmell and tafte, 
 difcovers no great heat or pungency, and is fo ponderous as to fink in water: 
 To which may be added, that the Oil of Pimento, like that of Cloves, refldes 
 chiefly in the fhell or cortical part, the internal fubftance yielding little or 
 none. (2.) That the heat and pungency are lodged in the Refln. In this re- 
 fpedl alfo Pimento agrees with Cloves ; but as Pimento in fubftance is far lefs 
 hot and fiery than Cloves, its Refin likewife is proportionably more mild. 
 This Refin differs further from that of Cloves, in having an ungrateful kind of 
 -tafte, fomewhac like that of an extradl made from green Walnut fhells ; and 
 appearing, when pure, of a deep green colour. This colour is obferved par- 
 ticularly in the tindlure and extradl made after the mucilaginous parts have 
 been feparated by water : A fingle grain of this extradl tinges half an ounce of 
 ipirit. The colour proceeds from the green pulp; and as nothing of it is dif- 
 coverable in the watery extradl made after ipirit, we may conclude that this 
 pulp, or at leaft its colouring matter, is a true Refin. (3.) That the gummy 
 parts have very little adlivity. An extradl made by water at firft contains a 
 little Refin along with the Gum, as one made by Ipirit at firft contains fome 
 Gum along with the Refin. Hence the flight tafte of the firft watery extradl, 
 and the pale unequal colour of the firft fpirituous extradl. 
 
 Redlified Spirit of Wine elevates nothing from this fpice in diftillation, the 
 Oil of Pimento being too ponderous to arile with fo light a fluid. The only 
 way of making a ipirit from it is, to difiblve fome of the Oil in pure Spirit of 
 Wine: An agreeable fpirituous water may be obtained by Ample diftillation 
 with proof fpirit, the watery phlegm in that liquor, carrying up a part of 
 the Oil. 
 
 BLACK' PEPPER is the fruit of a climbing plant growing in Malabar, 
 Java, and other parts of the Eaft-Indies. The eflential Oil of this Spice has a 
 ftrong and a very durable fmell, but in tafte it is one of the mildeft of the di- 
 Hilled Oils, having no confiderable pungency or heat. It is elevated in part 
 by redlified Spirit of Wine, the diftilled Ipirit being impregnated with the fla- 
 vour though not with the pungency of the Pepper. The fpirituous extradl is 
 exceflively fiery : The watery alfo is very hot and biting, but this menftruum 
 cannot be made to extradl all the hot matter of the Pepper : Four ounces of 
 Pepper treated with more than twenty frefti quarts of water, ftill retained a bit- 
 ing tafte ; what the water extradled, fo long as it extradled any thing, was 
 likewife biting. 
 
 Sixteen ounces of Pepper yielded with water ten ounces of gummy extradl, 
 and afterwards with redtified ipirit three drams of Refin: Another pound, 
 treated firft with fpirit, gave two ounces two drams of refinous extradl ; and 
 afterwards with water feven ounces four drams two fcruples of gummy matter : 
 
 This 
 
Plants and their Parts, 
 
 This laft extrad had ftill home degree of pungency, rectified fpirit feeming not 
 to take up all the active parts any more than water. Of effential Oil, I have 
 gained two drams and a half from a pound. 
 
 The White-pepper has the fame kind of tafte and favour with the black, White, 
 but in a much lefs degree. It agrees alfo with the black in the nature of it s 
 chemical principles, only the flavour refiding in the diftilled Oil, and the puiu 
 gency and heat in the matter left after the diftillation. In effed, it is the very 
 
 lame fruit, gathered before it has grown fully ripe, 
 Hein by fteeping in water and then rubbing it. 
 
 and freed from the outer 
 
 CUBEBS, Cubebs, are fmall dried fhrivelled berries, of Indian growth, XVII, 
 greatly refembling Pepper- corns, but with this difference^ that each Cubeb is C u b e b s. 
 furnifhed with a pedicle, whilft the Pepper- berries come forth ciofe upon the 
 ftalk without pedicles : Hence Cubebs are called, not improperly, Piper can- 
 datum. Of the plant which produces them, we have no fatisfadory account. 
 
 Cubebs are in fmell fomewhat different from Pepper, in tafte fimilar, but lefs 
 pungent. Their effential Oil is equally mild ; the pungency, as that of Pep- 
 per, refiding in the refinous parts ; but redified fpirit,. which elevates in diftilla- 
 tion a part of the Oil of Pepper, brings over nothing from Cubebs. 
 
 Two ounces of Cubebs yielded with redified fpirit five drams ten grains of 
 ex t. raft, and afterwards with water four drams thirty- two grains, fix drams and 
 a half remaining undiffolved. The fame quantity, treated firft with water, 
 gave fix drams and a fcruple, and afterwards with fpirit only one dram and 
 one grain : The refiduum weighed ieven drams two fcruples, Wedel relates 
 that three pounds afford two ounces and a half of effential Oil. 
 
 GRAINS of PA R AD I S E have been fuppofed to be the feeds of the XVIIL 
 larger Cardamom formerly mentioned (page 402.) but very erroneoufly. In Grains "of 
 fmell, tafte, and chemical compofition, they are quite different from Carda- Paradise. 
 mom-feeds. Grains of Paradife are pungent as Pepper *, and their pungency v— > 
 does not refide, like that of Cardamoms, in the effential Oil, but in the Refin. 
 
 The diftilled Oil poffeffes their fmell, but in tafte proves mild, whilft the re- 
 finous extrad is exceflively pungent, the fmalleft particle fetting the tongue as 
 it were on fire, and continuing to burn the mouth for fome hours. 
 
 ROSEW OO D, Lignum rhodium , afpalathus , a hard ponderous wood faid XIX. 
 to be the produce of the ifland Rhodes, and fome of the Fortunate Elands, Rhodium, 
 approaches in fmell to Rofes, and yields a delightful Oil commonly employed 
 as a perfume. This wood is commonly crooked, twilled as it were, unequal 
 and full of protuberances, covered with a rough brownifh-grey bark, which 
 eafily comes off ; the wood itfelf is of awhitifti colour on the outfide, and of a 
 darker brownifh, yellow, or orange colour within : It is chiefly in this Eft 
 part that the Oil and other adive matter refide, and the yellower the colour 
 the more Oil it contains. The Dutch carefully pick out for diftillation the 
 largeft, fmootheft, leaft twilled and darkeft coloured pieces. The fmell of this 
 wood is often not to be diftinguifhed in entire pieces, but on fawing or rafping 
 themacrofs, till we come to the yellow part, it never fails to difcover itfelf. 
 
 H h h Viel- 
 
4i 8 Plants and their Parts. 
 
 Rhodium. Vielheuer relates, that a pound ofRhodium yielded an ounce of Oil : If this 
 
 w j be true, the wood muft have been of an extraordinary good kind. I have 
 
 gained in England, three drams from a pound, never more, and for the moft 
 part not near fo much. The common Oil ofRhodium is grievoufly adulte- 
 rated, not as fome fuppofe, by adding exprefled Oils in the diftillation, for in 
 this cafe they would not arife with it, but by mixing them with it afterwards : 
 From an ounce of the very bed Oil ofRhodium I could procure for money, I 
 feparated fix drams two fcruples of exprelfed Oil ; and there was reafon to be- 
 lieve, that even the remaining four lcruples were not purely from the Rho- 
 dium. The Oil arifes in diftillation very flowly and difficultly, requires a. 
 ftrong boiling heat, and the diftillation to be once or twice repeated, by return- 
 ing the diftilled water upon therefiduum. The water is ftrongly impregnated 
 with the flavour of the Rhodium, and is ufed for the fame purpofes as Role- 
 water : Rectified fpirit brings over nothing from this wood, but diftils a pure 
 flavourlels fpirit as it was employed. Hence extracts made by water conlift 
 only of the mucilaginous and bitterifh matter of the wood (for the wood in 
 fubftance has a fenftble bitternefs,) whilft the fpirituous retain all its volatile 
 odorous parts. 
 
 An ounce of the rafped wood yielded with redtified fpirit fifty-five grains of 
 refinous extradt, and afterwards with water thirty grains of Mucilage: The 
 
 •fame quantity, treated firftwith water, gave forty-five grains of mucilaginous 
 extradt, and afterwards with fpirit twenty- five grains of Refin: The indiflo- 
 luble woody matter weighed in the firft cafe fix drams thirty grains, and in the 
 latter ten grains more. 
 
 XX. YELLOW-S AUNDERS, Santalum citrinum or flavum , a compadt 
 Yellow- heavy pale yellow wood brought from the Eaft-I.ndies, is likewife employed 
 Saunders, principally in perfumes, though often alfo medicinally as a corroborant. It 
 has an agreeable fweet fmell, fomewhat of the mulky kind ; and yields an Oil 
 of excellent fragrance, though in no very large proportion: From fixteen 
 ounces of the rafped wood, digefted fome days in fait water, I obtained by 
 cohobation two drams : It was of a thickiffi confiftence, approaching to that 
 of a balfam. 
 
 Two ounces of this wood yielded with water two drams of gummy extradt, 
 and afterwards with redtified fpirit one dram and a half of Refin : Spirit, ap- 
 
 plied at firlft, extradted from the fame quantity two drams and a half, and water 
 extradted afterwards one dram. The diftilled water contained the flavour of 
 the wood, but from this fmall quantity no adtual Oil could be collected : The 
 diftilled fpirit had no flavour, the refinous extradt retaining all the adtive parts 
 of the Saunders. 
 
 XXL THE roots of the Sassafras tree, a native of feveral parts of America, 
 Sassafras, as Brazil, Florida, Virginia, &c. have a ftrong aromatic fmell refembling that 
 v- — j of Fennel. The fmall branches approach in quality to the roots ; the bark of 
 the trunk is much weaker; the wood of the trunk has hardly any fmell, and is 
 employed only for mechanic ufes. The roots are brought over with the bark 
 upon them, this being much ftronger in fmell than the woody part, whereas 
 
 in 
 
p 
 
 L A N T S 
 
 and 
 
 taei r 
 
 A R T S. 
 
 in fome other odoriferous woods the bark is inodorous. The wood of Saffafras Sassafras. 
 is of a brownifh colour -, the bark of a reddifh- brown, unequal, eafv to break : 
 
 Both are remarkably light. 
 
 Boerhaave’s obfervation, that light woods eafily exhale their Oil, does not 
 obtain here, notwithftanding he brings this very wood as an example of it. 
 
 The Oil of Saffafras arifes very difficultly in diftillation with water, and not at 
 all with fpirit : Notwithftanding the lightnefs of the wood, the Oil is fo pon- 
 derous as to fink in water-, Hoffmann finds that it is the heavieft of all the 
 effential Oils. This gentleman gained, from fix pounds of the wood, an ounce 
 and fix drams of Oil : From the fame quantity of middling Saffafras I obtained 
 two ounces, fo that we may reckon at leaft eight fcruples upon the pound, or 
 half a fcruple upon an ounce. 
 
 An ounce of Saffafras digefted with rectified fpirit yields four fcruples of 
 extract, and afterwards with water a dram: Water applied firft extrads two 
 drams, and fpirit afterwards- only feven grains and a half. The Oil is the 
 moft adive part of the Saffafras, and next to this the fpirituous extract, which 
 contains all the Oil along with the Refin. Infufions however, or flight decoc- 
 tions, made like thofe of Bohea Tea, are no contemptible preparations, the 
 water by this treatment, extrading and retaining greateft part of the virtue of 
 the root. 
 
 The ufe of Saffafras is almoft wholly medicinal, as a corroborant and puri- 
 fier of the blood. Ximenes relates, and from him Wormius, that this wood, 
 macerated for a time in fea- water, fweetens or frees it from its faltnefs : Fran- 
 cifcus Redi found from experiment that it had not this effed. 
 
 LIGNUM-ALOES, Xyloaloes , Agallochum , is an oriental wood, very XXII 
 fcarce and valuable in the Eaftern countries, and very rarely brought into L IGNl m- 
 Europe, though the compilers of difpenfatories dired it as an ingredient in a loes 
 fundry compofitions, and require it to be taken frefh and fragrant. The tree , \ 
 
 has hitherto eluded the enquiries of European travellers. It is faid, that the 
 Lignum- aloes is the medullary part of the tree 5 and that there are different 
 forts of it, of which only the worft comes to us, the beft being twice as dear 
 upon the fpot as ours is here. Rumphius relates, that the Chinefe counterfeit 
 it with another Indian wood, boiled, or infufed, with reffnous aromatic 
 extrads. 
 
 Lignum-aloes is very differently defcribed by different authors. The beft 
 that we meet with in this country is very compact, heavy, fomewhat gloffy, of 
 a chefnut-brown colour intermixed with a blackifh and fometimes a purple, in 
 fmell refinous and balfamic : The largeft, heavieft, darkeft coloured, and moft 
 refinous pieces are preferred. Ihavefeena veffel which held a quart made 
 from one piece. 
 
 Half an ounce of this wood, rafped, yielded with redified fpirit five fcruples 
 and a half of refinous extrad, and afterwards with water one fcruple of a 
 gummy one : Another half ounce, treated firft with water, gave three 
 fcruples and a half, and afterwards with fpirit one dram : The indifi'olubie 
 woody matter amounted in both cafes to five drams and a half. Floffmann 
 fubmitted ten pounds of the rafped wood to diftillation with water, and ob- 
 
 H h h 2 tai ned 
 
420 P l ants and their Part s. 
 
 LiG.NyM- tained only half an ounce of eflential Oil, which coagulated in the cold into at. 
 Aloes, refmous or Camphor-like confidence. 
 
 XXIII. THE roots of Elecampane, Enula camp ana, Helenium, [Helenium vulgar e 
 El eg a m- C.B.) yield indead of a fluid Oil, a fubftance which concretes partly into 
 pane, lnowy flakes, and partly into an undtuous confident mafs like foftifh Wax. 
 
 Ondiftilling thirty- two ounces of the root, I gained in all three fcruples and. 
 a half; of which part duck in the head of the dill, part in the worm, and part 
 pa fled down into the receiver along with the water. I have not obtained i'uch 
 a concrete from any other vegetable : It is not a true Camphor, though agree- 
 ing with it in feveral properties as well as in the manner of its production. It 
 dilfolves in Spirit of Wine, and is not adted upon by water: Laid on burning 
 coals, it totally exhales : Held over a gentle fire in a ladle, it flows like Wax 
 or Tallow, and when cold appears fofter and more undtuous than at find.:. It 
 never aflum.es a crydalline form, but when thoroughly - dry proves opake and 
 crumbly: When newly diddled, it fmells confiderably of the Elecampane, but 
 on keeping for fome time, it lofes its more fubtile parts, and no longer difcor 
 vers any remarkable fmell. I know of no one who has taken notice of this* 
 concrete, except the younger Geoflfoy, who obferves. that itrefides in the ex- 
 terior parts of the root, near to the bark. 
 
 The tade of this root is bitterifh and aromatic ; its fmell moderately drong 
 and not difagreeable. The mod adtive preparation is the fpirituous extradf* 
 rectified fpirit bringing over nothing in didillation : Even the watery extradt 
 however is not deditute of adlivity, for water leaves more behind than it car- 
 ries up. An ounce of the dry root yielded with water fix drams and a half of 
 extrad: The fame quantity gave with fpirit only two drams and a half Af- 
 ter the fpirit would take up no more, water extracted five drams ; but the parcel 
 that had undergone the adion of water gave only five grains to fpirit. 
 
 XXIV. INDIAN SPIKENARD (Nardus Indica, qua fpica , fpica nardi <hf 
 Spikenar o. fpica Indica officinis C. B.) confids of a number of (lender brittle filaments, fup- 
 v— pofed by fome to be the root, by others the pedicle of the leaves,, of a plant of 
 the Grafs or Rufh kind but which are properly the head of a root, for Pomet 
 mentions and figures a fpecimen which had great part of the root itfelf adhering.. 
 
 Spikenard has a very drong, not agreeable fmell and tade, fcarce to be con^ 
 cealed or overpowered by a large admixture of other fubdances : In the Theriaca 
 ccskfih) a compofition of many drugs of drong fmells and tades. Spikenard, 
 enters but in fmall quantity, and yet it prevails over all the others. It contains 
 however only a fmall proportion of eflential Oil •, On diftilling an ounce, there 
 was only an appearance of fome oily particles on the. furface of the water;. 
 Rectified fpirit brings over nothing : The fpirituous extract poflefles both the 
 fmell and tade of the Spikenard, in a much greater degree than the watery. 
 An ounce yielded a dram of fpirituous, and afterwards forty-fix grains of wa- 
 tery extrad : Water applied at fird extradited from the fame quantity four 
 fcruples, and fpirit afterwards twenty-five grains : The indifioluble refiduum 
 weighed in both cafes fix drams ten grains. 
 
 THE 
 
421 
 
 Plants and their Past s. 
 
 THE Arabian Staechas ( Stcechas purpurea C. B.) is a fmall fhrubby XXV, 
 plant, growing not only in Arabia, but in fome of the fouthern parts of Eu- French 
 rope, particularly in the Stsechades or Hieres iflands on the coaft of France, Lavender, 
 The flowery heads or fpikes are an officinal drug : Thefe, when in perfedlion, are ' — «v— 
 of a fragrant fmell, and a bitterifli tafte ; but they are not gathered it feems 
 till they are ready to fhed the flowers, which in drying fall off completely, 
 leaving nothing to be brought to us [at Berlin] butalmoft inodorous hulks. 
 
 An ounce of our bell Staechas yielded with redtified fpirit a dram and twelve 
 grains of extract, and afterwards with water five fcruples and a half, the refi- 
 duum weighing five drams all but two grains. On inverting the order of pro- 
 cedure, the watery extract weighed three drams ten grains, the fpirituous only 
 eight grains, and the refiduum four drams forty grains. The fpirituous ex- 
 tract contains the whole of the tafte and aromatic flavour : The watery extradt 
 taftes alio confiderably of the Staechas. The diftilled water has nothing valu- 
 able, though the frefh flowers yield a portion of adtual Oil. 
 
 THE leaves of Hyssop ( Hyjfopus officinarum carulea five fpicata C. B. ) yielded XXVI. 
 a dram and a half of Oil upon two pounds, the diftilled water retaining alfo aHvsso p.i. 
 confiderable quantity, fo as to fmell ftrongly of the herb. Redtified fpirit ele- » * 
 
 vates the more fubtile parts of this Oil, but foon lets them go upon ftanding, 
 and lofes nearly all the fmell which it had when newly diftilled. The extracts 
 have not much of the diftinguifhing tafte, any more than of the fmell of the 
 Hyffop : The fpirituous has more than the watery. 
 
 An ounce of the dried leaves gave half an ounce of watery, and afterwards 
 twelve grains of fpirituous extradt : Redtifted fpirit applied at firft extradted from 
 the fame quantity two drams, and water afterwards two drams more : The 
 indiftoluble matter weighed in both cafes half an ounce. This plant is chiefly 
 recommended in coughs and obftrudtions of the breaft. 
 
 THE leaves of Feverfew ( Matricaria , Parthenium: Matricaria vulgaris XXVII 
 feu fativa C. B. fo called from their ufe in uterine obftrudtions,) have a bitterifh Feverfew. 
 tafte, and a ftrong fmell, to moft people difagreeabie, fuppofed to be peculiarly i__ — -- — j 
 offenfive to bees, whence Paulli advifes thole who expole themfelves-- to thefe 
 infedts, to carry Feverfew as a defence. 
 
 Pure fpirit elevates little of the Oil of this plant ; and hence in the fpirituous 
 extradts, its diftinguifhing fmell as well as tafte is preferved. Water on the 
 contrary elevates all the Oil, which partly remains diffolved in the diftilled 
 water and communicates to it a ftrong impregnation, and partly feparates in 
 its proper form. 
 
 An ounce of the dried leaves yielded with redtifled fpirit three drams five 
 grains of refinous extradt, and afterwards 1 with water five fcruples of a gummy' 
 one : Another ounce, treated firft with water gave four drams and a fcruple of 
 gummy extradl:, and afterwards with fpirit one dram of Refin : The refiduum 
 in the firft cafe weighed three drams ten grains, in the latter only two drams 
 forty grains. 
 
 R.U E„ 
 
42 2 
 
 P.L an t s and their Parts, 
 
 XXVIII. RUE, broad and narrow leaved {Rut a hortenfis latifolia C. B. Rut a lor- 
 Rue. tenfis altera ejufdemd) has a ftrong difagreeable fmell, and a naufeous, acrid, bit- 
 J tertafte: Some have obferved, that the frefh juicy leaves, bruifed and applied 
 to the fkin, corrode and exulcerate it ; but that when dry they have not this 
 effed : They are ufed in medicine as a {Emulating aperient and anthelmintic. 
 
 It is fuppofed, that the feeds and their capfules are more adive than the 
 leaves. Thus much is certain, that if the plant be diftilled, feeds and all, 
 when the feeds are about half ripe, it yields a larger quantity of effential Oil 
 than at any other time. It is obftrvable of this Oil, that it coagulates in the 
 cold like Oil of Ani feeds; a property, however, which does not conftantly 
 obtain, and which perhaps may depend upon the degree of maturity of the 
 feeds. 
 
 Two ounces of the dried leaves yielded with redified fpirit five drams and a 
 half of extrad, and afterwards with water five drams wanting half a fcruple, 
 the refiduum weighing five drams two fcruples : Water applied firft extraded 
 from the fame quantity nine drams, and ipirit afterwards only two fcruples, 
 the refiduum amounting to fix drams and a fcruple. The extrads made both 
 by water and fpirit at firft, are bitter and acrid ; the firft fpirituous is fomewhac 
 oily ; the fecond watery is manifestly faline. The diftilled fpirit has little or 
 no impregnation from the Rue. 
 
 XXIX. THE leaves of Scordium or Water-germander [Cham^drys paluftris cane - 
 Scordium . fcens feu fcordium officinarumTourn.) have a bitterifh tafte, and a ftrong fmell re- 
 c— v — —j fembling that of Garlic. In diftillation however, we- cannot, from moderate 
 quantities, colled any adual Oil, its proportion being very Small, fo as to be 
 almoft wholly retained in the diftilled water, to which .it communicates the 
 fmell of the herb. Both the watery and fpirituous extrads are bitter: The 
 fpirituous is the ftrongeft, and poffefles the fmell and flavour as well as the bit- 
 ternefs of the Scordium, pure fpirit elevating nothing of its Oil in diftillation. 
 
 An ounce of the dried leaves of Scordium yielded with water four drams and 
 a half of gummy extrad, and afterwards with redified fpirit fifteen grains of 
 Refin : Another ounce, treated firft with fpirit, gave three drams of refinous 
 extrad, and afterwards with water five fcruples and a half of Gum : The refi- 
 duum in the firft experiment weighed three drams fifteen grains, in the latter 
 five grains lefs. 
 
 This plant is greatly celebrated as a diaphoretic and alexipharmac : In thefe 
 intentions an eflfence or fpirituous tindure of it is frequently made ufe of in 
 Germany. A tindure made in highly redified fpirit contains more of the 
 adive parts of the Scordium, than one made with a phlegmatic fpirit, though 
 the latter, by dififolving more of the mucilaginous parts, proves thicker and 
 apparently more faturated : The firft tindure is of a fine green colour, the 
 other inclines more to a dark brownifh. 
 
 CLASS 
 
Plants and their Parts. 
 
 
 A 2 % 
 
 a d9 
 
 CLASS VII. 
 
 SALINE VEGETABLES. 
 
 T H E acid juices of fruits, as Citrons and Lemons, effervefce with and j ( 
 
 neutralize alcalies, dilfolvethe abforbent earths, and fome metallic bo- Saline. 
 dies, as Iron, Copper, and Lead. They contain befides their truly acid part, i v _ 
 a large quantity of grofs mucilaginous or undluous matter: Hence the juices Lemon juice. 
 
 themfelves, and molt of the folutions made in them, are apt to 
 
 foon^' 
 
 mouldy in keeping. The metallic folutions are lefs fubjedt to this inconveni- 
 ence than the earthy, and fome juices lefs than others : A folution of Iron in 
 the juice of the apples called Golden-rennets, evaporated to a thick conliftence, 
 proves an elegant Chalybeate, which keeps well. The juices give over very 
 little acid in diftil Iation ; nor have they been obferved to cryftallize into a folid 
 Salt, like thofe of fome acid herbs as Wood-forrel (/). 
 
 WOO D-S ORREL ( Acetofella , lujula, alleluja , oxys : 'Trifolium acetofim vul- II, 
 gare flore albo C. B . ) is a fmall plant, growing wild in woods and meadows : It S o r r e l, 
 is faid to cover itfelf with its leaves on the approach of ill weather. The frefh 
 leaves have a mild acid take, much more agreeable than that of common Sor- 
 rel, without any remarkable fmell. Their expreffed juice is employed medi- 
 cinally for cooling and quenching thrift ; and the elfential Salt, extracted from 
 it by cryftaliization, for taking out iron moulds and fpots of ink from linen j 
 for this purpofe, the ftained part is dipt in water, fprinkled with a little of the 
 powdered Salt, then rubbed on a pewter-plate, after which the fpot is walked 
 out with warm water. 
 
 Twenty pounds of frefla Sorrel-leaves yielded fix pounds of juice 5 from 
 which were obtained two ounces two drams and one fcruple of cry ftalline Salt, 
 together with two ounces and fix drams of an impure faline mafs. The matter 
 remaining after the exprefficn, being treated with water and with fpirit, gave 
 ten ounces and a half of watery, and afterwards five drams of fpirituous ex- 
 tract : The indiffoiuble matter, from the whole twenty pounds, amounted to 
 no more than three ounces and three drams. 
 
 The elfential Salt has a great agreement with Tartar, and yields the fame 
 produdtson being examined by fire. It is not however, as fome pretend, a true 
 Tartar : The principal differences are s that it is fenfibly more acid, turns Syrup 
 
 of 
 
 (/) Do not crfftaliize .]. It appears to be the 
 mucilaginous parts of thefe juices that pre- 
 vent the cryftallization of the faline ; and 
 that the faline parts are capable of being pu- 
 rified from the mucilaginous. From the 
 juices of Oranges and Lemons, I have fepa- 
 rated the infipid Mucilage, and obtained the 
 acid matter in form of a truly cryftalline 
 white Salt. Probably by the fame manage- 
 ment, the acid and fvveet juices of other 
 
 fruits might be made to afford perfect Salts 
 retaining all the fpecific tafte of the fruit. 
 
 How far the native acid juices agree or dif- 
 agree with Vinegar and Tartar, the products 
 of fermentation, is littleknown. They leem to 
 approach neareft to the nature of Tartar, as 
 being fufceptible of a cryftalline form, giv- 
 ing over little of their acid in diftillation, , 
 and yielding in the refiduum, a large portion., 
 of fixed alcalL, 
 
424 Plants and their Part s. 
 
 Sorrel.oF Violets red, whilft Tartar makes no change in the colour, contains lefs oily 
 
 , / matter, diffolves more eafily in water, and does not feparate from the folutiom 
 
 It holds near a dram of Oil upon the ounce: On diftilling an ounce in a re- 
 tort, a fcruple of Oil is obtained in its proper form, the other two fcruples be- 
 ing partly diffipated in the operation, and partly imbibed by the fpiric that 
 comes over at the fame time. 
 
 III, THEfweet faline fubflance of Casia Fistularis (for it appears to be 
 C a s 1 a. truly of the faline kind) diflolves not only in water but in rectified Spirit of 
 
 ~^~~***j Wine. Cafia is the fruit of a tree growing in Egypt and in both the Indies : 
 It is a large cylindrical pod or cane, containing, under a hard rind, a foft pulp 
 lodged in a number of tranfverfe cells, with a Hat roundifh feed in each. The 
 pulp is apt to grow four or mouldy upon long keeping, even before its extrac- 
 tion from the cane : Sometimes alfo it grows dry, fo as that the feeds rattle in 
 the cells upon fhaking the pod ; in this ftate it is generally rejected, though the 
 fimple exficcation cannot be of any prejudice, as nothing but the aqueous hu- 
 midity exhales. 
 
 The pulp of Cafia, when in perfection, is of a Aiming black colour, a fweet 
 tafte followed by a difagreeable relifh, and a faint unpleafant kind of fmeJl. It 
 is commonly extracted by bruifing the pod, boiling it in water, and evaporat- 
 ing the (trained decoCtion to a due confiftence. Out of four drams of the dry 
 pulp, water diffolved three drams fifteen grains, and rectified fpirit as much or 
 very nearly fo •, but the fpirit aCted more flowly and difficultly than the water. 
 The diitilled water frnelt and tailed a little of the Cafia ; the fpirit not. 
 
 This pulp is a gentle laxative, and very frequently ufed in that intention by 
 the French : The dofe, to an adult, is two ounces diffolved in fome convenient 
 liquor with the addition of a carminative to prevent its occafioning flatulencies 
 and gripes, which of itfelf it is very apt to do, efpecially when grown fouriffi. 
 It is laid to tinge the urine, when taken in moderate quantity, green ; and in 
 a larger quantity, brown or blackifh. 
 
 IV. THE Ca rob, Caroba , ceratia , ' filiqua dulcis, is a pod of the fame kind, 
 
 C a r o b. about a fpan long, of a flattifh figure, containing a brown coloured fweet pulp, 
 > 1 which is ufed by the Egyptians and Arabians as Sugar. The tree is found wild 
 
 alfo in fome of the fouthern parts of Europe : It is raifed among us in the gar- 
 dens ol the curious, but does not in this climate ripen its fruit. 
 
 The pulp of theCarob is diffolved more effectually by water than by fpirit. 
 Out of fixteen drams of the dry pulp, water took up eleven drams; reClififd 
 fpirit extracted from the remainder only five grains, leaving five drams of mere 
 ffiells or membranes. The fame quantity, treated firft with fpirit, gave out but 
 nine drams ten grains, and afterwards to water five fcruples, five drams and ten 
 grains being left. The watery extraCt is fweeter and more agreeable than the 
 fpirituous : The fpirituous extraCt made after water is manifeffly unCtuous : 
 The watery extraCt made after fpirit difcovers fome faline matter. The watery 
 decoCtions are ofa reddifh-brown colour, and in infpiffation turn almoft black : 
 The fruit gives a deep colour to many freffi parcels of water. Spirit on the 
 other hand foon ceafes to extraCt any tinCture, and the firlt deepelt tinCture is 
 
 5 onl X 
 
Plants and their Part s. 
 
 only of a yellovvifh-brown : Neverthelefs, the fpirituous ex trad made after C a 
 water inclines to black. t— 
 
 IT is probable that the fweetnefs of Liquorice, and of vegetable fweets in 
 general, depends on a faline fubftance of the nature of Sugar, intimately Liqu 
 blended, as Sugar is in the juice of the cane, with unduous, mucilaginous, or Q— 
 refinous matter. Rectified Spirit of Wine diffolves the faccharine Salts and 
 as it takes up but little of the mucilaginous principle (the ingredient whofe 
 quantity is the greateft,) the fpirituous tindures and extrads prove confiderably 
 fweeter than the watery. The fpirituous extrad of Liquorice is exceedingly 
 fweet, the watery far lefs fo. From two ounces of the dry root I obtained by 
 redihed fpirit only five drams, whilfl the fame quantity yielded with water nine 
 drams: After the fpirit would take up no more, water extraded three drams 
 and a half ; but after the adion of water, fpirit gained only half a dram : The 
 indiffoluble earthy matter amounted in the firft cafe to feven drams and a half, 
 in the latter only to fix and a half. The fweetnefs of this root is accompanied 
 with a flight bitteri flinefs, which fome fuppofe to be confined to the outer brown 
 fkin, but which is found to be equally diftributed through the inner yellow 
 part : The peeling of Liquorice is therefore entirely unneceffary, unlefs for ob- 
 taining a paler coloured powder or a lighter tindure. 
 
 It has been faid that Liquorice is indilpofed to ferment, and hence it is re- 
 commended particularly to thofe, who cannot well bear Sugar, Honey, or the 
 more fermentable fweets : Experiment fliews however that it does ferment, 
 and yield a truly vinous liquor. 
 
 The extrad of Liquorice is a confiderable article of commerce : It is made 
 in large quantity in Spain, and in fome parts of Germany, particularly at Bam- 
 berg. The Spanifh, which is generally covered with Bay leaves, is the belt 
 and pureft ; the other has a large admixture of the rob or infpiffated juice of 
 Plums, &V. A certain writer affirms that an ounce of the Bamberg extrad, 
 treated with water afreffi, will fcarcely give out two drams, but I have never 
 met with any fo bad as this : An ounce gave upwards of feven drams, though 
 it does not follow that the whole of that quantity was genuine extrad of 
 Liquorice, as the rob of Plums will diffolve in water as well as that of 
 Liquorice. 
 
 Out of an ounce of the Spanifh extrad, water dilfolved feven drams two 
 fcruples, only one fcruple being left, from which fpirit extraded nothing : 
 Redihed fpirit dilfolved but four drams two fcruples out of an ounce-, water 
 extraded three drams from the refiduum, a fcruple remaining as before undif- 
 folved. An ounce of the Bamberg fort yielded with water feven drams one 
 fcruple : The fame quantity gave with fpirit two drams fifty grains, and after- 
 wards with water three drams and a half; two fcruples in the former, and five 
 in the latter cafe, remaining undiflolved. The part which fpirit took up con- 
 tained nearly all the fweetnefs ; that which water extraded afterwards having 
 fcarcely any tafte. The Dutch fupply us now with no fmall quantity of what 
 is called Spanifh Liquorice, and do not fail to wrap it up in plenty of Bay-* 
 leaves. 
 
<? 
 
 * 
 
 426 Plants and then * Part 
 
 VI, THE flowers of many plants are remarkably fweet : Thofe of Mullein 
 Mullein. mas latifolium luteum C. B.) contain a Honey-like juice. An ex- 
 
 trad made by water from the flowers is exceedingly fweet and pleafant : In the 
 fpirituous extract, a kind of peculiar flavour is joined to the fweetnefs. 
 Twenty-four drams of the flowers yielded with water twelve drams and a half, 
 and afterwards with redified fpirit one dram and a half : Spirit applied firft, 
 extraded from the fame quantity nine drams, and water afterwards four and a 
 half. The leaves of Mullein have no fweetnefs, and contain lefs diffoluble 
 matter than the flowers : Twenty-four drams gaveeight and a half of watery, 
 and afterwards one and a half of fpirituous extrad : On inverting the order of 
 applying the menftrua, the fpirituous extrad weighed four drams and a half, 
 and the watery fix. 
 
 ANOMALOUS VEGETABLES. 
 
 ^HE R E are fome vegetables which cannot be referred to any of the fore- 
 going claffes, nor indeed to any other, the principle, in which their peculiar 
 qualities refide, being as yet wholly unknown. The common Arum or Wake- 
 robin is a plant of extreme acrimony : The frefh root, flightly chewed, feems 
 to burn and corrode the tongue ; and oftentimes its pungent impreffion con- 
 tinues for two or three days. The feat of this acrimony has hitherto eluded our 
 enquiries : The diddled water and fpirit have nothing of it, and the watery and 
 fpirituous extrads exceeding little and yet the root is by thefe operations de- 
 prived of it. 
 
 Greateft part of the acrimony is deftroyed by fimple exficcation : The dry 
 root appears white and farinaceous, and affeds the tongue but little. In this 
 date it is given medicinally for attenuating vifcid juices : Formerly it was ufed 
 as flare h for linen, before the difcovery of that from wheat (m), and is faid to 
 have occafioned a rawnefs and forenels of the hands very difficultly relievable 
 by ointments : In fome parts of France, it is dill employed in bleaching, be- 
 ing fuppofed, by its corrofive quality to diffolve unduofities and make the 
 linen white. 
 
 0») Starch. ] Common Starch is prepared, 
 by macerating Wheat in water renewed once 
 or twice a day, till k burfts eafily betwixt 
 the fingers and gives out a kind of white 
 Creme: This, fqueezed through a canvas 
 bag, and macerated with frefh parcels of 
 water, forms a tenacious fecula ; which, af- 
 ter the water is poured off, is taken out in 
 pieces and dried flowly in the fun. A me- 
 thod has lately been difcovered and commu- 
 nicated in the Swedifh Tranfa&ions, of 
 making Starch from Potatoes. For this 
 purpofe, the Potatoes are laid in water 
 
 From 
 
 twelve hours, then fkinned, foaked again 
 for two hours longer, afterwards ground, 
 moiftened, preffed through a hair-fieve, the 
 pulpy matter boiled with water, fuffered to 
 fettle, and treated with frefh parcels of wa- 
 ter till the liquor comes off as clear as it 
 was put on : When the laft water is poured 
 off, the remaining Starch is dried in the fun, 
 or other very gentle heat. By this procefs, 
 five pounds of Potatoes yielded eight ounces 
 and three quarters of fine Starch, and one 
 ounce of coarfe. Boiled Potatoes did not 
 fucceed. 
 
Plants and their Parts. 
 
 From an ounce of the dry root I obtained fcarcely a fcruple of fpirituous ex- 
 trad : The fame quantity yielded of watery extradl, near three drams. The 
 firft had fome flight pungency ; the latter none. 
 
 THE fine dull of Lycopodium or Puffball is called by fome, on account Lycopo- 
 of its great inflammability, vegetable Sulphur. The Puffball is the feed-velfel DIUMo 
 of a fpeciesof Mofs named by Tournefort Mufcus fquamofus vulgaris repens cla- < » 
 
 vat us j and the duft is properly the feeds of the plant. There are fundry other 
 vegetables, as Polypodies, Ferns, Coniferous trees, &c. whofe feeds are a like 
 yellow impalpable Farina, fo fubtile as to be blown away by the lead; motion of 
 air : It is this duft which has given rile to fome reports of fhowers of Brim- 
 ftone. 
 
 The duft of Lycopodium, diffufed or ftrewed in the air, takes fire from a 
 candle, and burns off like a fiafh of iightning, with a confiderabie noife : A 
 quantity laid together upon burning coals, does not flame, but ftnokes away, 
 with a fetid fmell : Burnt in a red-hot crucible, it leaves a very frnall propor- 
 tion of a light cobweb-like matter. It does not, as fome report, take fire from 
 Flint and Steel, nor explode like Gunpowder 5 nor does it feem to detonate 
 more violently with Nitre than other inflammable matters do. Olearius re- 
 lates, that the Ruffians employ much of it in fire-works, but does not inform 
 us in what manner. 
 
 This fubftance, chemically analyfed, appears to contain a refinous matter, 
 and an oily one of the. expreffible kind, intimately combined together, fo as to 
 be both extradled, at leaft in part, by rectified Spirit of Wine : On infpiffating 
 the tindlure, the Oil feparated, remained permanently fluid, and would not 
 unite again even with the refinous extradl : It is remarkable, that pure fpirit 
 would no longer touch this Refin any more than the Oil. The quantity thus 
 extracted from an ounce of the powder amounted only to a dram : Water did 
 not take up near fo much •, it was with great difficulty I obtained by water 
 eight grains of extradl from an ounce. Both the water and fpirit arofe in di- 
 ftillation unchanged. 
 
 By deftrudtive diftillation in an open fire, I gained a large proportion of em- 
 pyreumatic Oil, no lefs than two ounces and a half from four: This was pre- 
 ceded, not by an acid liquor, which moft vegetables yield on the fame treat- 
 ment, but by an urinous one •, the black Coal remaining in the bottom of the 
 diftilling veffel weighed five drams. 
 
 AS Cork ftoppers fometimes affedt the colour or the tafte of liquors, it may R 
 
 be proper to beftow fome experiments on this fubftance in that view. Cork is - _ — ^ 
 
 the bark of a tree of the Oak kind, growing in France, Italy, Spain, and fome 
 other parts of Europe: The French Cork is the whiteft, the Span ifh the fofteft 
 and moft efteemed. The bark is taken off every three years, preffed flat, 
 dried, and then fcorched on the outfide to preferve it from infedls. 
 
 Cork boiled in water communicated a brownifh colour, and on evaporating 
 the decodlions, there remained two fcruples of folid extradl from an ounce : 
 
 The refiduum, digefted in rectified fpirit, gave out eleven grains. Spirit ap- 
 plied at firft extradted two fcruples and two grains froth an ounce, and water 
 
 I i i 2 afterwards 
 
 427 
 
 A R u 
 
 M. 
 
428 Plants and their Parts, 
 
 Cork, afterwards eight grains. The fpirituous tin dure was yellowifh, paler in colour 
 than the watery, but ftronger in tafte : From all the fpirituous tindures a 
 powdery matter precipitated, of a reddifh colour from thofe made at firft, and 
 of an afh-grey when the Cork had been previoufly treated with water. 
 
 I likewife macerated fmall pieces of Cork in different liquors fet in a gently 
 warm place : Diftilled Vinegar and Spirit of Vitriol were tinged the leaft ; 
 Aqua fort is became fomewhat yellower, and almoft wholly corroded and dif- 
 folved the Cork; dulcified Spirit of Vitriol, folution of common Salt, dul- 
 cified Spirit of Nitre, Spirit ofSea-falt, Lime-water, and dulcified Spirit of 
 Sea-falt, acquired, (in the order they are here enumerated) more and more of 
 a yellowifh tinge; Syrup of Violets, dulcified Spirit of Sal ammoniac, and 
 TinCture of Tartar, gained a deeper brownifli-yeliow ; watery Spirit of Sal 
 ammoniac, Oil of Tartar per deliquium, and vinous Spirit of Sal ammoniac 
 with Quick-lime, received the deepeft reddifh tindlure of all the liquors exa- 
 mined. In fund ry ti natures, which had been palled through a filter and ap- 
 peared perfectly clear, Cork occafioned a fenfible turbidnefs and precipitation, 
 particularly Tindtura Tartari, which diffolves a confiderable quantity of the 
 Cork. The change of colour of Syrup of Violets is not a little extraordinary. 
 
 Cotton Cotton («), affords not one of thofe principles on which the foregoing ar- 
 \j rangement of vegetables is built. It gives out no gummy or faline matter to 
 
 water, 
 
 (ft) Cotton.'] In the Swedifh Tranfafilions 
 for the year 1 747, a method is given of 
 preparing Flax fo as to refemble Cotton, in 
 whitenefs and foftnefs, as well as in cohe- 
 rency. For this purpofe, a little fea-water 
 is dire&ed to be put into an iron pot or an 
 untinned copper kettle, and a mixture of 
 equal parts of Birch allies and Quick-lime 
 ftrewed upon it: A fmall bundle of Flax is 
 to be opened and fpread upon the furface, 
 and covered with more of the mixture, and 
 the ftratification continued till the veffel is 
 fufficiently filled. The whole is then to be 
 boiled with fea-water for ten hours, frelh 
 quantities of water being Occafionally fup- 
 piied, in proportion to the evaporation, that 
 the matter may never become dry. The 
 boiled Flax is to be immediately waftied in 
 the lea, by a little at a time, in a balket, 
 with a fmooth jftick, : When grown cold 
 enough to be born the hands, it mull be 
 well rubbed, walhed with Sope, laid to 
 bleach, and turned and watered every day. 
 Repetitions of the walhingwith Sope expe- 
 dite the bleaching ; after which, the Flax is 
 to be beat, and again well walhed : When 
 dry, it is to be worked and carded in the 
 fame manner as common Cotton, and preffed 
 
 betwixt two boards for twice twenty-four 
 hours. It is now fully prepared and fit for 
 ufe : It lofes in this procefs near one half 
 of its weight, which is abundantly compen- 
 fatedby the improvement made in its quality. 
 
 The filamentous parts of different vege- 
 tables have been employed in different coun- 
 tries, for the fame mechanic ufes as Hemp 
 and Flax among us. Putrefaction deftroys 
 the pulpy or flelhy matter, and leaves the 
 tough filaments entire : By curioully putre- 
 fying the leaf of a plant in water, we ob- 
 tain the fine flexile fibres, which conllituted 
 the balls of the ribs and minute veins, and 
 which now form as it were a Ikeleton of the 
 leaf. Alcaline Lixivia, in fome degree, 
 produce fimilar effefits to putrefaction. 
 
 The Sieur de Flacourt, in his Hillory of 
 Madagafcar, relates, that different kinds of 
 cloth are prepared, in that illand, from the 
 filaments of the bark of certain trees boiled 
 in llrong Ley ; that fome of thefe clothes 
 are very fine, and approach to the foftnefs of 
 Silk, but in durability come lhort of Cot- 
 ton ; that others are coarler and ftronger, 
 and laft thrice as long as (potton ; and that 
 of thefe, the fails and cordage of his veffel 
 were made. 
 
 The 
 
Plants and their Parts. 
 
 water, no refinous matter to fpirit, and no Oil in diftillation *, and Teems in 
 thefe kinds of experiments, a fi triple vegetable fibre. The force of fire, how- 
 ever, converts it like all other vegetable bodies into dilfimilar parts ; and here 
 it is found to be remarkably different from the animal filaments, Wool, Hair, 
 and Silk. It does not, like them, yield a fetid fmell when burnt in the open 
 air, nor any urinous Salt or Spirit in clofe veffels (<?). Eight ounces of Cotton, 
 
 diftilled 
 
 The fame author informs us, that the 
 jfalks of Nettles are ufed for the like pur- 
 pofes in his own country, France. And 
 Sir Hans Sloane relates, in one of his letters 
 to Mr. Ray, that he has been informed by 
 fevera!, that Muflin and Callico, and molt 
 of the Indian linens, are made of Nettles. 
 
 In fome of the Swedifh provinces, a 
 Itrong kind of cloth is faid to be prepared 
 from Hop-ftalks : And in the Tran factions 
 of the Swedilh Academy for the year 1750, 
 there is an account of an experiment made 
 in confequence of that report. Of the 
 ftalks, gathered in autumn, about as much 
 was taken, as equalled in bulk a quantity of 
 Flax, that would have produced a pound af- 
 ter preparation. The ftalks were put into 
 water, and kept covered therewith during 
 the winter: In March they were taken out, 
 dried in a Hove, and drelTed as Flax. The 
 prepared filaments weighed very nearly a 
 pound, and proved fine, foft and white : 
 They were fpun, and woven into fix ells of 
 fine ftrong cloth. The author, Mr. Schif- 
 fler, obferves, that Hop-ftalks take much 
 longer time to rot than Flax ; and that if 
 not fully rotted, the woody part will not fe- 
 parate, and the cloth will neither prove 
 white nor fine. 
 
 (a) 'Difference from Wool , &c.] Vegetable 
 filaments, and thread or cloth prepared from 
 them, differ remarkably from Wool, Hair, 
 Silk and other animal productions, not only 
 in the principles into which they are refo- 
 luble by fire, but likewife in fome of their 
 more interefting properties, particularly in 
 their difpofition to imbibe colouring mat- 
 ters ; fundry liquors, which give a beautiful 
 and durable dye to thofe of the animal, giv- 
 ing no ftain at all to thofe of the vegetable 
 kingdom. 
 
 A folution of Copper in Aqua fortis, 
 which had been changed blue by an addition 
 of volatile fpirit, on being mixed with a little 
 folution of Tin, became turbid and greenifh. 
 5 
 
 Pieces of white Silk and Flannel boiled, 
 without any previous preparation, in this 
 mixture, received a bright deep yellow dye, 
 whilft pieces of linen, prepared and unpre- 
 pared, came out as colourlefs as they were 
 put in. 
 
 Fifhing-nets are ufually boiled with Oak 
 barker other like aftringents, which render 
 them more lafting. Thofe made of Flax 
 receive from this decoCtion a brownifh co- 
 lour, which by the repeated alternations of 
 water and air, is in a little time difeharged^ 
 whilft the fine gloffy brown, communicated 
 by the fame means to filken nets, perma- 
 nently refills both the air and water, and 
 Hands as long as the animal filaments them- 
 felves. In like manner the ftain of Ink, or 
 the black dye from folutions of Iron mixed 
 with vegetable aftringents, proves durable 
 on Silk and Woollen ; but from Linen, the 
 aftringent matter is extracted by walhing, 
 and only the yellow iron mould remains. 
 
 The red decodion of Cochineal, which, 
 heightened with a little folution of Tin, 
 gives the fiery fcarlet dye to Wool or Silk 
 that have been previoufly impregnated with 
 folution of Tartar, makes no imprelfion 
 upon Linen or Cotton prepared in the fame 
 manner. Mr. du Fay informs us, in the 
 Memoirs of the French Academy for the 
 year 1737, that having prepared a mixed 
 cloth whofe warp was of Wool and the 
 woof of Cotton, and thoroughly blended 
 the two together by fulling, he ftill found 
 the Cotton to refift the action of the fcarlet 
 liquor, and the Wool to receive the fame 
 colour from it as Wool by itfelf, the fluff 
 coming out all over marbled, fiery and 
 white. 
 
 Many other inftances of this kind are 
 known too well to the Callico-printer 5 
 whofe grand defideratum it is, to find means 
 of making Linen receive the fame colours 
 that Wool does. The phyficai caufe of 
 the difference is wholly unknown ; and in- 
 deed of the theory of dyes in general we 
 
 know 
 
43 ° 
 
 Cotton. 
 
 F l - a n t s and their Parts, 
 
 diftilled in 'a retort, gave over three ounces and a half of an acidulous, fuli- 
 ginous, oily Spirit, and about five drams of an empyreumatic Oil : The re- 
 maining coal, burnt in a crucible into white allies, weighed no more than four 
 fcruples, from which was obtained a fmall portion of fixed alcaline Salt. 
 
 Cotton is the produce of a middling fized tree, which grows fpontaneeufiy 
 in both the Indies : The feeds of the tree are bedded in this foft fubftance, 
 with an outer fhell over it. There are many other plants which bear a downy 
 or cottony matter : But the down is in molt of them unfit for being manu- 
 factured like Cotton ; the fibres being too coarfe, or too Ihort, to be fpun into 
 fine threads. There is a Cotton-plant in the Eaft-Indies, whofe down can be 
 emDloyed only for fluffing beds, and differs from the common Cotton more 
 remarkably in a great degree of inflammability : When it catches fire, it is faid 
 to be almoft inftantaneoufly and unextinguifhably confumed (n). 
 
 SECT. 
 
 know as yet extremely little. Are animal 
 filaments tubular, and the colouring atoms 
 received within them? Are vegetable fila- 
 ments folid, and the colour depofited on the 
 furface? Or does not their different fufcep- 
 tibility of colour depend rather on the diffe- 
 rent intrinfic properties of the two ? There 
 are many inftances of a like diverfity, even 
 in the metallic kingdom, where a mechani- 
 cal difference in texture can fcarcely be 
 prefumed to be the caufe : Thus Silver re- 
 ceives a deep ftain from fulphureous or pu- 
 trid vapours, or the yolk of a boiled egg, 
 which have no effect upon Tin. 
 
 («) ADDITIONAL ARTICLES. 
 
 >T“' HERE are many vegetable fubflances, 
 befides thofe above-mentioned, whofe 
 conftituent principles are. as yet fo imper- 
 fectly known, that we cannot, with pro- 
 priety, either refer them to any of the pre- 
 ceding claffes, or form any others that fhall 
 comprehend them. Such are particularly 
 the coloured flowers, leaves, &c. of plants, 
 confidered merely as fubjeCts of colour. And 
 indeed moll of the vegetable colours 
 might, perhaps, be properly ranked here ; 
 for though the colouring matter feems 
 in many, from its being extracted by Wa- 
 ter, to be of the gummy or gummy-refi- 
 nous kind ; yet, as it is procurable alfo in 
 the form of a lake not at all diffoluble either 
 by Water or by Spirit, (fee page 266.) it 
 cannot ftriCtly be looked upon either as refi- 
 nous or gummy. 
 
 FLOWERS. 
 
 AMONG the infinite variety of co- 
 
 lours, which glow in the flowers of 
 plants, there are very few which have any 
 durability, or whofe fugitive beauty can be 
 arrefted by art, fo as to be applied £0 any 
 valuable purpofes. The only permanent 
 ones are the yellow. The red, the blue, 
 and all the intermediate fhades of purples, 
 crimfons, violets, &c. are extremely perifh- 
 able. Many of thefe flowers lofe their co- 
 lour on being barely dried ; efpecially if 
 they are dried flowly, as has been ufually 
 direCled, in a fhady and not warm place. 
 The colours of all of them perifh, on keep- 
 ing, even in the clofeft veffels. The more 
 haftily they are dried, and the more per- 
 fectly they are fecured from the air, the 
 longer they retain their beauty. The co- 
 louring matter, extracted and applied on 
 other bodies, is ftill more perifhable : Of- 
 tentimes it is changed or deftroyed in the 
 hands of the operator. 
 
 BLUE FLOWERS. 
 
 'Tp El E colour of many blue flowers is ex- 
 traCted by infufion in Water ; but 
 there are fome, from which Water gains 
 only a reddifh or a purpiifh hue. Of thofe 
 that have been tried, there is not one which 
 gives any blue tinCture to fpirituous liquors: 
 Some give no colour at all, and fome a 
 reddifh one. The juice, preffed out from 
 the frefh flowers, is for the moft part 
 blue. 
 
 The 
 
Plants and their Parts. 
 
 43 1 
 
 The blue juices and infufions are changed 
 red by all acids : The marine acid feems 
 to ftrike the mod florid red. The flowers 
 themfelves, macerated in acid liquors, im- 
 part alfo a deep red tinTcure. Alcalies, 
 both fixed and volatile, and Lime-water, 
 change them to a green. Thole infufions 
 or juices, which have nothing of the na- 
 tive colour of the flower, fuffer the fame 
 changes from the addition of acid and alca- 
 line liquors : Even when the flowers have 
 been kept till their colour is loft, infufions 
 made from them acquire ftill a red colour 
 from the one, and a green from the other, 
 though in a lefs degree than when the flowers 
 were frefti. 
 
 The red colour produced by acids, is 
 fcarcely more durable than the original 
 blue : Applied upon other bodies, and ex- 
 pofed to the air, it gradually degenerates 
 into a faint purplifh, and at length difap- 
 pears, leaving hardy any ftain behind. The 
 green produced by alcalies, changes to a 
 yellow, which does not fade fo foon. The 
 green, by Lime-water, is more permanent 
 and more beautiful : Green lakes, prepared 
 from thefe flowers by Lime-water, have 
 been ufed as pigments by the painter. 
 
 The flowers of Cyanus have been greatly 
 recommended, as affording elegant and 
 durable blue pigments ; but I have never 
 been able to extract from them any blue 
 colour at all. They retain their colour in- 
 deed, when haftily dried, longer than feme 
 other blue flowers ; but they communicate 
 nothing of it to any kind of menftruum. 
 Infufions of them in watery, fpirituous, and 
 oily liquors, are all more or lefs of a red- 
 difh caft, without any tendency to blue. 
 Alum, which is faid to heighten and pre- 
 ferve their blue colour, changes it, like that 
 of other blue flowers, to a purplifh red; 
 acids to a deep red ; alcalies and Lime- 
 water to a green. Solution of tin, added 
 to the watery infufion, turns it to a fine 
 erimfon : On Handing, a beautiful red fe- 
 cula fubfides, but it lofes all its colour by 
 the time it is dry. The watery infufion, 
 infpiffated to the confiftence of an extract, 
 appears of a dark reddifh brown : An ex- 
 tract made with rectified Spirit is of a pur- 
 plifh colour. The colour of both extracts, 
 fpread thin and expofed to the air, quickly 
 fades The flowers employed in thefe ex- 
 
 periments were thofe of the common blue 
 
 bottle of the cornfields, Cyanus fegeium Flowers, 
 C. B. Cent a urea calycibus ferratis : folio lis line- \ — . — n 
 aribus integerrimis : inf mis dentatis Linn. Spec. 
 
 RED FLOWERS, 
 
 n ED flowers readily communicate their 
 own red colour to watery menftrua : 
 
 Among thofe that have been tried, there is 
 not one exception. Thofe of a full red 
 colour, give to rectified Spirit alfo a deep 
 red timfture, brighter, though fomewhat 
 paler, than the watery infufion : But the 
 lighter red flowers, and thofe which have 
 a tendency to purplifh, impart very little 
 colour to Spirit, and feem to partake more 
 of the nature of the blue flowers than of the 
 pure red. 
 
 Infufions of red flowers are fuppofed to 
 be heightened by acids, and turned green 
 by alcalies like thofe of the blue : But this 
 is far from being univerfal. Among thofe 
 I have examined, the rofe colours and pur- 
 plifti reds were all changed nearly in the 
 fame manner as the blues ; but the full 
 deep reds were not. The deep infufion of 
 red Poppies is turned by alcalies not to a 
 green, but to a dufky purple. 
 
 YELLOW FLOWERS. 
 
 Op H E colours of yellow flowers, whether 
 pale or deep, are in general durable : 
 
 Many of them are as much fo, perhaps, as 
 any of the native colours of vegetables. 
 
 The colour is extracted both by Water and by 
 Spirit: The watery infufions are the deepeft. 
 
 Neither acids nor alcalies alter the fpecies 
 of colour, though both of them vary its 
 fhade ; acids rendering it paler, and alcalies 
 deeper : Alum likewile confiderably heigh- 
 tens it, though not fo much as alcalies. 
 
 Wool or Silk, impregnated with a Solu- 
 tion of Alum and Tartar, receives, on be- 
 ing boiled with the watery infufion or de- 
 cofition, a durable yellow dye, more or lefs 
 deep according as the liquor is more or lefs 
 faturated with the colouring matter. An 
 infufion of the flowers made in alcaline ley, 
 precipitated by Alum, gives a durable yel- 
 low lake. Some of thele flowers, particu- 
 larly thofe of the Chryfanthemum or Corn- 
 marigold, appear (from the Ars tinbloria fun- 
 damentalis publifhed by Stahl) to be made 
 ufe of by the German dyers. 
 
 In 
 
CO 
 
 2 
 
 Plants and their Parts. 
 
 Flowers. In Tome of the deep reddilh yellow or 
 orange-coloured flowers, the yellow matter 
 feems to be of the fame kind with that of 
 the pure yellow flowers, but the red to be 
 of a different kind from the pure red ones : 
 Watery menftrua take up only the yellow, 
 and leave the red, which may afterwards 
 be extracted by redtified Spirit of Wine, or 
 by Water acuated with fixed alcaline Salt. 
 Such particularly are the faffron-colouted 
 flowers of Carthamus. Thefe, after the 
 yellow matter has been extradied by Water, 
 are faid to give a red tindlure to Ley ; from 
 which, on {landing at reft for fome time, a 
 deep bright red fecula fubfides ; called, 
 from one of the names of the plant which 
 produces it. Safflower ; and from the coun- 
 tries whence it is commonly brought to us, 
 Spanifh-red and China-lake. This pigment 
 impregnates Spirit of Wine with a beautiful 
 red tindlure, but communicates no colour to 
 Water. 
 
 I have endeavoured to feparate, by the 
 fame treatment, the red matter of fome of 
 the other reddilh yellow flowers, as thofe of 
 the garden Marigold ; but without fuccefs. 
 Plain Water extradied a yellow colour, and 
 alcaline ley extradied afterwards only a paler 
 yellow : Though the digeftions were con- 
 tinued till the flowers had loft their colour, 
 the tindlures were no other than yellow, 
 and not fo deep as thofe obtained from the 
 pure yellow flowers. 
 
 The little yellow flofculi, which in fome 
 kinds of flowers are colledled into a com- 
 padl round difc, as in the Daify and Corn- 
 marigold, agree, fo far as they have been 
 examined with the expanded yellow pe- 
 tala. Their colour is aft'edled in the fame 
 manner by acids, by alcalies, and by 
 Alum; and equally extradied by Water 
 and by Spirit. 
 
 But the yellow farina, or fine dull lodged 
 on the tips of the ftamina of flowers, ap- 
 pears to be of a different kind. It gives a 
 fine bright yellow to Spirit, and a duller 
 yellow to W ater ; the undiffolved part prov- 
 ing in both cafes of a pale yellowifh white. 
 Both the watery and lpirituous tindlures 
 were heightened by alcaline liquors, turned 
 red by acids, and again to a deep yellow or 
 adding more of the alcali. I know no other 
 vegetable yellow that is changed red by 
 acids. 
 
 WHITE FLOWERS. 
 
 Vy’HIT £ flowers are by no means de- 
 ** ftitute of colouring matter. Alcaline 
 lixivia extradl from fome of them a green 
 tindlure, and change their colourlefs ex- 
 preffed juices to the fame colour ; but I 
 have not obferved that they are turned red 
 by acids. The flowers of the common 
 wild Convolvulus or Bindweed, which in 
 all their parts are white, give a deep yellow 
 or orange tindlure to plain Water, which 
 like the tindlures of flowers that are natu- 
 rally of that colour, is rendered paler by 
 acids, heightened a little by Alum, and 
 more confiderably by alcaline Salts. The 
 vapours of the volatile vitriolic acid, or of 
 burning Sulphur, which whiten or deftroy 
 the colour of the coloured flowers, make no 
 change in the white. 
 
 FRUITS. 
 
 'T' H E red juices of Fruits, as red Cur- 
 A rants, Mulberries, Elderberries, and 
 Morello and Black Cherries, &c. gently in- 
 fpiffated to drynefs, difl'olve again almoft 
 totally in Water, and appear nearly of the 
 fame red colour as at firft. Redlified Spirit 
 extradls the tinging particles, leaving a 
 confiderable portion of mucilaginous matter 
 undiffolved : And hence the fpirituous tinc- 
 ture proves of a brighter colour than the 
 watery. The red folutions, and the juices 
 themfelves, are fometimes made dull, and 
 lometimes more florid, by acids j and gene- 
 rally turned purplifh by alcalies. 
 
 The colours of thefe juices are for the 
 moft part perifhable. They refill indeed 
 the power of fermentation, and continue al- 
 moft unchanged after the liquor has been 
 converted into Wine : But when the juice 
 is fpread thinly on other bodies, exficcated, 
 and expofed to the air, the colour quickly 
 alters and decays : The bright lively reds 
 change the fooneft : The dark dull red 
 ftain from the juice of the Black-cherry is 
 of confiderable durability. The fruit of the 
 American Qpuntia or prickly Pear, the 
 plant upon which the cochineal infedl is 
 produced, is perhaps an exception : This 
 bright red fruit, according to Labat, gives a 
 beautiful red dye. Some experiments how- 
 ever made upon the juice of that fruit, as 
 
 brought 
 
Plants and their Pa r t s. 
 
 433 
 
 brought into England, did not feem to pro- 
 mife any great advantage from it ; but the 
 particulars I cannot now recollect. 
 
 The ripe berries of Buckthorn ftain pa- 
 per of a green colour. From thefe is pre- 
 pared the fubftance called Sap-green, a pig- 
 ment diffidently durable, readily foluble in 
 "Water, but not mifcible with Oil. The 
 berries dried whilft green, and macerated 
 in Alum-water, are faid to yield a yellow 
 pigment ; and when they have grown over- 
 ripe, fo as to fall off fpontaneoufly, a pur- 
 ple one. Woollen cloth, prepared with 
 Alum and Tartar, receives, on being boiled 
 with the berries, a perifhable yellow dye. 
 The French berries, or Graine d' Avignon of 
 the French dyers, one of the moll falfe, that 
 is the moft perifhable, of the yellow dyes, is 
 the berry of a fpecies of Buckthorn, fmaller 
 than that which grows wild among us. 
 
 It is faid that the berry of the Heliotro- 
 piwn tricoccum , which grows wild about 
 Montpelier, ftains paper of a green colour, 
 and that this green turns prefently to a 
 blue : That the common blue paper re- 
 ceives its colour from this juice : And 
 that the red rags called Turnfol , employed 
 for colouring Wines and other liquors, are 
 tindfured by the fame juice turned red by 
 acids. According to M. NilTolle of the 
 French academy of fciences, (as quoted by 
 Savary in his Diclionnaire de commerce ,) the 
 colouring juice is obtained, not from the 
 berries, but from the tops of the plant, ga- 
 thered in Auguft, ground in mills, and then 
 committed to the prefs. The juice is ex- 
 pofed to the fun about an hour, the rags 
 dipt in it, dried in the fun, moiftened by 
 the vapour which arifes during the flaking 
 of Quick-lime with Urine, then dried 
 again in the fun, and dipt again in the juice. 
 The Dutch and others are faid to prepare 
 turnfol rags, and turnfol in the mafs, from 
 different ingredients, among which Archil 
 is a principal one. 
 
 In fome plants. Peony for inffance, the 
 feeds, at a certain point of maturity, are 
 covered with a fine fhining red membrane : 
 The Pellicles of the feeds of a certain Ame- 
 rican tree afford the red maffes brought into 
 Europe under the names of Annotto, Or- 
 lean, and Pvoucou. The red feeds, cleared 
 from the pods, are fleeped in Water for 
 feven or eight days or longer, till the liquor 
 begins to ferrhent ; then ftrongly ftirred, 
 
 and ffamped with wooden paddles andpRUJTS.. 
 beaters, to promote the feparation of the < ^ r 
 
 red fkins : This procefs is repeated feverai 
 times till the feeds are left white. The li- 
 quor, palTed through clofe cane fieves, is 
 pretty thick, of a deep red colour, and a 
 very ill fmell : In boiling, it throws up its 
 colouring matter to the furface in for-m of 
 fcum, which is afterwards boiled down by 
 itfelf to a due confidence, and made up 
 while foft into balls. 
 
 > The Annotto, commonly met with 
 among us, is moderately hard and dry, of 
 a brown colour on the outbid e, and a dull 
 red Within. It is difficultly adled upon by 
 Water, and tinges the liquor only of a pale 
 brownifh yellow colour. In rectified Spirit 
 of Wine, it very readily difTolves, and com- 
 municates a high orange or yellowifh red ; 
 
 Hence it is ufed as an ingredient in var~- 
 nifties, for giving more or lefs of an orange 
 caft to the fimple yellows. Alcaline Salts 
 render it perfedly foluble in boiling Water, 
 without altering its colour : Wool or Silk, 
 boiled in the folution, acquire a deep, but 
 not a very durable, orange dye. Its colour 
 is not changed by Alum or by acids, any 
 more than by alcalies ; but when imbibed 
 in cloth, it is difcharged by Sope, and de- 
 fcroyed by expofure to the air. 
 
 Mr. Pott, in the Berlin Memoirs for the 
 year 1752, mentions a very extraordinary 
 property of this concrete : “ With the vi- 
 “ triolic acid, it produces a blue colour, of 
 “ extreme beauty, but with this capital de- 
 
 fed:, that all Salts and Liquors, even 
 “ commonWater, deftroyit.” The fpecimen 
 of Annotto which I examined was not fen- 
 libly adfed on by Spirit of Vitriol : It re- 
 ceived no change in its own colour, and 
 communicated none to the liquor. Nor did 
 any vifible change enfue, upon dropping 
 the acid into tin&ures of Annotto made in 
 Water or in Spirit. 
 
 Labat informs us, that the Indians pre- 
 pare an Annotto greatly fuperior to that 
 .which is brought to us ; of a bright fhining 
 red colour, almoft: equal to carmine : That 
 for this purpofe, inftead of deeping and fer- 
 menting the feeds in W ater, they rub them 
 with the hands, previoufiy dipt in Oil, till 
 the pellicles come off and are reduced into 
 a clear pafte, which is feraped off from the 
 hands with a knife, and laid on a clean leaf, 
 in the fhade, to dry. De Fact, in his notes 
 K k k on 
 
434 
 
 Plants and their Parts. 
 
 Fruits. 
 
 v, — * 
 
 on Marcgrave’s natural hiftory of Brazil, 
 mentions alfo two kinds of Annotto ; one 
 of a permanent crimfon colour, ( Coccineus ) 
 ufed as a fucus ; and another, which gives 
 a colour inclining more to that of Saffron. 
 This lafb, which is our Annotto, hefuppofes 
 to be a mixture of the firft fort with certain 
 refmous matters, and with the juice of the 
 
 root of the tree- Ximenes relates, that 
 
 Annotto with urine ftains linen of fuch a 
 permanent colour, that it is never to be 
 wafhed out. Perhaps the firft fort is meant. 
 Our Annotto, boiled in urine, imparted to 
 linen a deep yellowifti red : The ftained 
 linen, hung out in the air in fummer, in 
 feven or eight days loft all its colour and 
 became white again. 
 
 LEAVES. 
 
 'T' H E green colour of the leaves of 
 plants is extracted by rectified Spirit of 
 Wine and by Oils. The fpirituous tindlures 
 are generaliy of a fine deep green, even 
 when the leaves themfelves are dull coloured 
 or yellowifh or hoary. The colour, how- 
 ever, feldom abides long even in the liquor; 
 much lefs when the tinging matter is fepa- 
 rated in a folid form, and expofed with a 
 large furfaee to the air. The editor of the 
 Wirtemberg Pharmacopeia obferves, that 
 the leaves of Acanthus, Brankurfine ©r 
 Bears-breech, give a more durable green 
 tmdlure to Spirit than thofe of any other 
 herb. Alcalies heighten the colour both of 
 the tindlures and green juices r Acids weak- 
 en, deftroy, or change it to a brownifh. 
 Lime-water improves both the colour and 
 durability: By means of Lime, not inele- 
 gant green lakes are procurable from the 
 leaves of Acanthus, Lily of the valley, and 
 feveral other plants. 
 
 There are very few herbs which commu- 
 nicate any {hare of their green colour to 
 Water ; perhaps none that give a green of 
 any confiderable deepnefs. It is faid, how- 
 ever, that the leaves of fome plants give a 
 green dye to woollen, without the addition 
 of any other colouring matter ; particularly 
 thofe of the wild Chervil or Cow-weed, 
 ( Myrrhis fylve/iris femnlbus lav'ibus C. B.) 
 the common Ragwort, and Devils-bit. The 
 procefs with this laft, as defcribed by Lin- 
 nteus (in the Svenjka acacl . handl, drs , 1742.) 
 
 is pretty remarkable. The peafants, he in- 
 forms us, in fome of the Swedifh province?, 
 ftratify the frefti leaves with woollen yarn, 
 and boil them about as long as it is cuf- 
 tomary to boil fifh. The whole is fuffered 
 to ftand in the veffel for a night : The 
 wool, taken out in the morning, does not 
 appear to have received any colour. The 
 pot is again made hot, and the yarn hung 
 over it, upon a flick, covered with an in- 
 verted difh to confine the fleam, for this 
 fleam is fuppofed to be eflential to the 
 colour. The yarn is afterwards wrung, the 
 leaves taken out of the boiling liquor, a lit- 
 tle frefh Water added to the decodlion, and 
 the wool frequently dipt therein, till it ap- 
 pears fufficicnty coloured. 
 
 The leaves of many kinds of herbs and 
 trees give a yellow dye, to wool or woollen 
 cloth that has been previoufly boiled with a 
 folution of Alum and Tartar : Weld in par- 
 ticular affords a fine yellow, and is commonly 
 made ufe of for this purpofe by the dvers, 
 and cultivated in large quantity in fome 
 parts of England. There is no colour for 
 which vine have fuch plenty of materials as 
 for yellow. Mr. Hellot obferves, in his 
 Art de teindre , that all leaves, barks, and 
 roots, which on being chewed difcover a 
 flight aflringendy, as the leaves of the Al- 
 mond, Peach and Pear-trees, Afh bark, 
 (efpecially that taken off after the firft rifing 
 of the fap in fpring) the roots of wild Pa- 
 tience, CC. yield durable yellows, more or 
 lefs beautiful according to the length of 
 time that the boiling is continued, and the 
 proportions of Alum and Tartar in the pre- 
 paratory liquor : That a large quantity of 
 Alum makes thefe yellows approach to the 
 elegant yellow of Weld : That if theTartar 
 is made to prevail, it inclines them to an 
 orange : That if the roots, barks or leaves 
 be too long boiled, the yellow proves tar- 
 nifhed, and acquires fhades of brown : That 
 for dying with Weld, the beft proportions 
 of the Salts are, four parts of Alum, and one 
 of Tartar, to fixteen of the wool ; and that 
 the wool, prepared with thefe, is to be 
 boiled again with five or fix times its quan- 
 tity of Weld : That for light fhades, it is 
 cuftomary to diminifh the Alum, and omit 
 theTartar; and that in this cafe, the co- 
 lour is more flowly imbibed, and proves lefs 
 durable* 
 
 * 
 
 Of 
 
Plants and their Par 
 
 Of ail the colours of the dyer, we have 
 the feweft materials for blue. The mineral 
 and animal kingdoms afford none ; except- 
 ing perhaps Pruffian blue, which Mr. Mac- 
 quer has lately attempted to introduce into 
 this art (fee page 73.) The vegetable 
 yields but two, which are both produced 
 from the leaves of plants, indigo and 
 woad. 
 
 fooner or later according to the warmth of 
 the weather and the maturity of the plant, 
 fometimes in fix or eight hours, and fome- 
 times not in lefs than twenty. The liquor 
 grows hot, throws up a plentiful froth, 
 thickens by degrees, and acquires a blue 
 colour inclining to violet. At this time, 
 without touching the herb, the liquor im- 
 
 INDIGO. 
 
 INDIGO, one of the capital manufac- 
 
 tures of America, is prepared from a 
 fmall, flefhy, foft leaf, of a greenifh brown 
 colour on the upper-fide, pale and as it 
 were filver-coloured underneath. The plant, 
 called Anil or Nil, has feveral flender knotty 
 ftalks, which fpread into fmall branches, 
 clothed each with from four to ten pair of 
 thefe leaves and an odd one at the end : It 
 rifes to the height of about two feet, and 
 produces reddifh flowers, in fhape refem- 
 bling thofe of broom, but fmaller, followed 
 by oblong pods, containing the feeds. 
 
 Labat has given a particular account of the 
 culture of the plant, and the preparation of 
 the Indigo — The ground being thoroughly 
 cleared from weeds (one of the principal 
 points in the culture) a number of Haves, 
 ranged in a line, march acrofs, making lit- 
 tle trenches of the width of their hoes and 
 two or three inches deep, about a foot drf- 
 tant from one another every way : Then, 
 returning, they drop fome feeds in each 
 trench, and afterwards cover them with the 
 earth taken out. In moift weather, the 
 plant comes up in three or four days ; and in 
 about two months after, it is fit for cutting: 
 If fuffered to ftand till it runs into flower, 
 the leaves become too dry and hard, and the 
 Indigo obtained from them proves lefs in 
 quantity, and lefs beautiful : The due 
 point of maturity is known, by the leaves 
 beginning to grow lefs fupple, or more 
 brittle. In rainy feafons, the cutting may 
 be repeated every fix weeks : Cutting in 
 dry weather kills the plant, which, if that 
 is avoided, continues to afford frefh crops 
 for two years. 
 
 A large quantity of the herb is put into 
 a vat or ciftern of ftrong mafon work, with 
 fo much Water as is fufficient to cover it ; 
 and fome wood laid above, to prevent its 
 rifing up. The matter begins to ferment, 
 
 pregnated with its tindture is let out, by 
 cocks in the bottom, into another vat 
 placed for that purpofe fo as to be com- 
 manded by the firft. 
 
 In the fecond vat, the liquor is ftrongly 
 and incefiantly beat and agitated, with a 
 kind of buckets fixed to poles, till the co- 
 louring matter is united into a body. A 
 good deal of nicety is requifite in hitting 
 this point : If the beating is ceafeb toofoon, 
 a part of the tinging matter remains dif- 
 folved in the liquor ; if continued a little 
 too long, a part of that which had feparated 
 is diffolved afrefh. The exadf time for dif- 
 continuing the procefs is determined, by 
 taking up fome of the liquor occafionaily in 
 a little cup, and obferving whether the blue 
 fecula is difpofed to feparate and fubfide. 
 
 The whole being now fuffered to reft till 
 the blue matter has fettled, the clear Water 
 is let off, by cocks in the fides at different 
 heights ; and the blue part difcharged by a 
 cock in the bottom, into another vat. Here 
 it is fuffered to fettle for fome time longer, 
 then further drained in cloth bags, and ex- 
 pofed in fhallow wooden boxes to the air 
 till thoroughly dry. 
 
 The author above-mentioned, from 
 whom the whole of the foregoing account is 
 extracted, obferves further, that the good- 
 nefs of the Indigo depends greatly upon the 
 age of the plant 5 that before it has grown 
 fully ripe, the quantity it yields is lefs, but 
 the colour proportionably more beautiful ; 
 that probably the fecret of thofe, whofe In- 
 digo has been moftefteemed, is no otherthan 
 cutting the herb at the time when it yields 
 the fineft colour ; that the fuperiority of 
 fome of the Indigoes of the E aft-indies to 
 thofe of America, is perhaps owing to the 
 former being prepared more curioufiy from 
 only the leaves of the plant ; and that by 
 beating the herb in the fteeping-vat, which 
 has been praftifed by fome with a view to 
 increafe the quantity, great part of the fub- 
 ftance of the leaves and bark is blended 
 with the Water along with the colour- 
 K k k 2 ins 
 
+3 6 
 
 Indigo, 
 
 Plants and 
 
 ing matter, and the Indigo extremely 
 de baled. 
 
 It is laid that Lime or Lime-water is 
 fometimes employed in the beating-vat, to 
 promote the 1'eparation of the tinging par- 
 ticles from the Water; and that the hard- 
 nefs or flintinefs of fome forts of Indigo is 
 owing to an over proportion of this ad- 
 dition. 
 
 Indigo is commonly divided, from the 
 colour which it exhibits upon breaking, 
 into three kinds, copper-coloured, purple, 
 and blue : It is faid that the dyers ufe 
 chiefly the firft ; and the callico-pxinters 
 (for this drug gives a durable Lain to linen 
 as well as woollen) the laft. On what 
 particular circumftances thefe different ap- 
 pearances depend, we know not ; nor is it 
 certainly known, whether the real quality 
 of the Indigo has any connexion with them. 
 The deepeft and livelieft blue Indigo, rub- 
 bed with the nail, looks like polifhed Cop- 
 per; and folutions of all the forts, made in 
 alcaline lixivia, affume alike a copper-co- 
 loured Akin upon the furface. 
 
 Good Indigo is moderately light, breaks 
 of a fhining furface, and burns almoft wholly 
 away upon a red hot iron. It is quickly 
 penetrated by Water, and reduced into a 
 kind of pafle : A confiderable part is at the 
 fame time diffufed through the liquor, and 
 very flowly fubfides : This is probably what 
 Labat and Hellot mean by its diffolving in 
 Water, for no part of the Indigo really dif- 
 folves ; it cannot indeed be expected that it 
 Ihould, from the prccefs by which it is 
 obtained. 
 
 Indigo requires an equal quantity or 
 more of fixed alcaline Salt, to render it to- 
 tally foluble in Water. On digefting the 
 Indigo, with a gentle heat, in the folution 
 of the alcaline Salt, a fhining copper-co- 
 loured fkin begins to appear, and gradually 
 covers the whole furface : On agitating the 
 matter, a large blue flower or froth arifes, 
 and the liquor underneath appears of a deep 
 green. If woollen cloth, without any other 
 preparation than moiftening it with warm 
 Water, be dipt in this hot liquor, it comes 
 out perfectly green, and changes almoft in- 
 ifantly in the air to a fine blue. This is 
 the common procefs of dying blue. 
 
 Mr*. Hellot defcribes two Indigo vats 
 with urine ; one of which is ufed hot like 
 the foregoing, and the ether cold. The. 
 
 their Parts. 
 
 hot vat confifts of equal parts of Indigo, 
 Alum, and Tartar, digefted in urine till 
 the liquor becomes green. The cold one is 
 prepared, by digefting powdered Indigo 
 with Vinegar for twenty-four hours, in the 
 proportion of four pounds to about three 
 quarts ; then mixing the matter with about 
 fifty gallons of urine, and ftirring the whole 
 together every night and morning, till the 
 liquor turns green, and gathers a head like 
 the common vat. 
 
 Indigo is fitted for printing on linen, by 
 diluting it with Water into the confiftcnce 
 of a fyrup ; then adding fome powdered 
 Pearl-afhes, green Vitriol, and Lime newly 
 flaked ; with fo much Water, occ-afionally, 
 as will reduce them into the confiftence 
 of thin paint ; mixing the whole thoroughly 
 together, and ftirring the matter every now 
 and then, till it gains a copper colour on 
 the furface. The proportions ufed by the 
 workmen are, two parts of Indigo, one of 
 Pearl-afhes, three of Vitriol, and two of 
 Lime. 
 
 The fame compofition, diluted with a 
 fufficient quantity of Water (about fix gal- 
 lons to a pound of Indigo) and boiled, gives 
 a durable blue to tanned fkins, whether 
 dipt in it hot or cold. 
 
 Indigo, digefted in a moderate heat with 
 different volatile alcaline fpirits, gave only 
 yellowifh and brownifh red tinffures ; with 
 rectified Spirit of Wine, a reddifh one : To 
 Lime-water, and to Water acidulated with 
 the vitriolic, nitrous and marine, acids, it 
 gave no tindfure at all. 
 
 The concentrated vitriolic acid unites 
 with it into a fmooth pafte, efpecially if the 
 Indigo is previoufly well ground with pow- 
 dered glals, land, or other like fubftances ; 
 The Indigo is thus rendered foluble in boil- 
 ing Water along with the acid, fo as to 
 pals through the pores of a filter : The fo- 
 lution, whilft hot, appears of a deep bright 
 green colour, like that made by fixed alca- 
 fies, but fades as it grows cold, and changes 
 at laft to a brownifh. 
 
 Thefe, experiments, which were many 
 times repeated with the fame event, feern 
 to overturn Mr. Hellot’s ingenious theory ; 
 which deduces the green colour of folutions 
 of Indigo from the common property of 
 blue juices of being turned green by alca- 
 Jies ; and the blue colour which the cloth 
 acquires loon after it is taken out of die vat. 
 
Plants and their Parts. 
 
 A 
 
 from a reparation of the alcali. We here 
 find, that a green folution of this concrete 
 is obtainable by the ftrongeft of the acids, 
 and that with volatile alcalies itdifcovers no 
 tendency to greennefs. 
 
 The folution of Indigo in Oil of Vitriol 
 does not appear green till boiled. The 
 thick compound, dropt into Water no hot- 
 ter than the hand can bear, communicates 
 a bright blue colour : Woollen cloth or 
 filk, prepared with Alum and Tartar, ac- 
 quire from this liquor the beautiful but pe- 
 rifhable blue dye called Saxon blue. The 
 Saxon green is dyed, by dipping the fluff 
 a fecond time in the yellow decodfion of 
 F ufticlc ; or more compendioufly, by mix- 
 ing the acid blue compofition with that de- 
 cocfion at once, till the liquor has gained 
 the depth of colour required. 
 
 I have been informed that the dyers of 
 Norwich, who purchafed this fecret from 
 Saxony, prepare the blue compofition by 
 grinding nine parts of Indigo with twenty of 
 red Arfenic; then addingto them, in a glazed 
 veffel, forty-eight parts of Oil of Vitriol, 
 and Purring them well together : After the 
 mixture has flood for twenty-four hours, 
 it is ft for ufe. In Mr. Hellot’s procefs, 
 received likewife from Germany, the pro- 
 portions are fomewhat different ; and in- 
 ilea d of red Arfenic, Cobalt and Orpiment 
 are ufed. Thefe differences are immaterial : 
 The only ufe of the additional matter feems 
 to be, to divide the Indigo, and render it 
 more eafily mifcible with the acid. I have 
 fucceeded, in (mall fpecimens, with red and 
 with white Arfenic, with Orpiment and 
 with Cobalt, with Sulphur, with Antimony, 
 with powdered Glafs,with powdered Sand, 
 and with Flint. 
 
 The Indigo, in the diluted blue liquors, 
 is perfectly diffolved, lb as to pafs through a 
 filter. The folutions, haftily evaporated to 
 the confiftence of a Syrup, become turbid 
 and green. On How evaporation, they con- 
 tinued uniform and blue, and readily min- 
 gled again with frefh water, palling the filter 
 as before- of a fine blue colour. 
 
 W O A D. 
 
 TT/'QAD, Ifatis, Glajlum , is a plant 
 * * with long green leaves ; the lower 
 ones narrow at both ends ; thofe which grow 
 upon the llalk broad at bottom like an ar- 
 
 row head On the tops come forth numer- W gad. 
 
 ous yellow flowers, which are followed by t — v — , » 
 
 little flat pods containing the feeds. It 
 
 grows wild in feme parts of France, and on 
 
 the coalls of the Baltic fea: The wild 
 
 Woad, and that which is cultivated for the 
 
 ufe of the dyers, appear to be the fame fpe- 
 
 cies of plant. 
 
 The preparation of Woad for dying, as 
 jr radii fed in France, is minutely deferibed 
 by Aftruc, in his memoirs for a Natural 
 Hiftory of Languedoc-— -The plant puts 
 forth at firft five or fix upright leaves, about 
 a foot long and fix inches broad : When 
 thefe hang downwards, and turn yellow, 
 they are fit for gathering : Five crops are 
 gathered' in one year. The leaves are car- 
 ried direbtly to a mill, much refembling the 
 oil or tan-mills, and ground into a fmooth 
 pafte. If this procefs was deferred for-fome 
 time, they would putrefy, and fend forth an 
 infupportable ftench. The pafte is laid in 
 heaps, preffed clofe and fmooth, and the 
 blackifti cruft, which forms on the outfide, 
 reunited if it happens to crack : If this was 
 neglebted, little worms would be produced, 
 in the cracks, and the Woad would lofe of 
 its ftrength. After lying for fifteen days, 
 the heaps are opened, the cruft rubbed and 
 mixed with the infide, the matter formed 
 into oval balls, which are preffed clofe and 
 folid in wooden moulds. Thefe are dried 
 upon hurdles: In the fun, they turn black 
 on the outfide ; in a clofe place, yellowifh, 
 efpecially if the weather is rainy : The 
 
 dealers in this commodity prefer the firft, 
 though it is faid the workmen find no confi- 
 derable difference betwixt the two. The 
 good balls are diftinguifhed by their being 
 weighty, of a pretty agreeable fmeli, and 
 when rubbed, of a violet . colour within — 
 
 For the ufe of the dyer, thefe balls require a. 
 further preparation : They are beat with 
 wooden mallets, on a brick or ftone floor, 
 into a grofs powder ; which is heaped up in 
 the middle of the room to the height of four 
 feet, a fpace being left for palling round the 
 fides. The powder, moiftened with water, 
 ferments, grows hot, and throws out a thick 
 fetid fume. It is {hovelled backwards and 
 forwards, and moiftened every day for 
 twelve days ; after which, it is ftirred lefs 
 frequently, without 'watering, and at length 
 made into a heap for the dyer. 
 
 The powder thus prepared, gives only 
 
 brown ilk 
 
 co 
 
43 8 Plants and 
 
 \V o A D. brownifh tin£fures, of different fhades, to 
 
 i i water, to rectified Spirit of Wine, to vola- 
 
 tile alcaline fpirits, and to fixed alcaline 
 Lixivia: Rubbed on paper, it communi- 
 cates a green ftain. On diluting the pow- 
 der with boiling water, and after ftanding 
 for fome hours in a clofe vefiel, adding a- 
 bout one twentieth its weight of Lime newly 
 flaked, digefting in a gentle warmth, and 
 ftirring the whole together every three or 
 four hours, a new fermentation begins, a 
 blue froth arifes to the furface, and the li- 
 quor, though it appears itfelf of a reddifh 
 colour, dyes woollen of a green, which, 
 like the green from Indigo, changes in the 
 air to a blue. This is one of the niceft 
 proceffes in the art of dying, and does not 
 well fucceed in the way of a fmall experi- 
 ment. 
 
 Aftruc propofes the manufacturing of 
 frefh Woad leaves in Europe, after the fame 
 manner as the Indigo plant is manufactured 
 in America ; and thus preparing from it a 
 blue fecula fimilar to Indigo, which from 
 his own experiments he lias found to be 
 practicable. Such a management would 
 doubtlefs be accompanied with fome advan- 
 tages, though poffibly, Woad fo prepared 
 might lofe thofe qualities which now render 
 it, in a large bufinefs, preferable on fome 
 accounts to Indigo, as occafioning greater 
 difpatch when once the vat is ready, and 
 giving out its colour lefs haftily, fo as to 
 be better fitted for dying very light 
 fhades. 
 
 Hellot fufpeCts, that a like blue fecula is 
 procurable from many other vegetables. 
 Blue and yellow, blended together, compofe 
 a green : He fuppofes the natural greens of 
 vegetables to be compounded in like manner 
 of thofe two colours ; and that the blue is 
 oftentimes the moil permanent, fo as to re- 
 main entire after the putrefaCfion or de- 
 ilruCtion of the yellow. The theory is fpe- 
 cious, and perhaps juft: We know of no 
 other that accounts, in any degree, for the 
 production of the Indigo and Woad blue. 
 In the experiments, however, which I have 
 made, of putrefying different herbs in wa- 
 ter, the blue and the yellow colour, if the 
 green was really compofed of thefe, were 
 both deftroyed together, no appearance be- 
 ing obferved either of one or the other dur- 
 ing the whole procefs. 
 
 i 
 
 their Parts. 
 
 MOSSES. 
 
 '’THERE are fundry Moffes, which in 
 A their natural ftate, like the tv/o fore- 
 going plants, promife nothing of the elegant 
 colours, which art calls forth from them. 
 
 Archil, Archill a , Rocella , Qrjeille, a whitifh 
 Mofs growing upon rocks in the Canary and 
 Cape Verd iflands, yields a rich purple tinc- 
 ture, fugitive indeed, but extremely beauti- 
 ful. 1 his weed is imported to us as it is 
 gathered : I hole who prepare it for the ufe 
 of the dyer, grind it betwixt ftones, fo as to 
 thoroughly bruife but not reduce it into 
 powder, and then moiften it occafionaliy 
 with a ftrong Spirit of Urine, or Urine itfelf 
 mixed with Quick-lime : In a few days it 
 acquires a purplifh red, and at length a blue 
 colour: In the firft ftate it is called Archil, 
 in the latter Lacmus or Litmafe. 
 
 The dyers rarely employ this drug by it- 
 felf, on account of its dearnefs and the pe- 
 rifhablenefs of its beauty. The chief ufe 
 they make of it is, for giving a bloom to 
 other colours, as pinks, &c. This is effected 
 by palling the dyed Cloth or Silk through 
 hot water lightly impregnated with the 
 Archil. The bloom thus communicated 
 foon decays upon expofure to the air. Mr. 
 Hellot informs us, that by the addition of a 
 little folution of Fin, this drug gives a dur- 
 able dye ; that its colour is at the fame time 
 changed towards a fcarlet ; and that it is 
 the more permanent, in proportion as it re- 
 cedes the more from its natural colour. 
 
 Prepared Archil very readily gives out its 
 colour to water, to volatile fpirits, and to 
 Spirit of Wine : It is the fubftance princi- 
 pally made ufe of for colouring the fpirits of 
 thermometers. As expofure to the air de- 
 ftroys its colour upon cloth, the exclufion 
 of the air produces a like effeift in thefe her- 
 metically fealed tubes ; the fpirits of large 
 thermometers becoming in the compafs of a 
 few years colourlefs. M. l’Abbe Nollet 
 obferves (in the French Memoirs for the 
 year 1742) that the colourlefs fpirit, upon 
 breaking the tube, foon refumes its colour, 
 and this for a number of times fucceflively ; 
 that a watery tindture of Archil, included in 
 the tubes of thermometers, loft its colour 
 in three days ; and that in an open deep 
 veffel, it became colourlefs at the bottom, 
 whilft the upper part retained its colour. 
 
 A fo- 
 
Plants and their Parts. 
 
 439 
 
 A folution of Archil in water, applied on 
 cold Marble, ftains it of a beautiful violet or 
 purplifh-blue colour, far more durable than 
 the colour which it communicates to other 
 bodies. Mr. du Fay fays he has feen pieces 
 of Marble ftained with it, which in two 
 years had fuffered no fenfible change. It 
 finks deep into the Marble, fometimes above 
 an inch ; and at the fame time fpreads upon 
 the furface, unlefs the edges be bounded by 
 Wax or other like fubftances. It feems to 
 make the Marble fomewhat more brittle. 
 
 Linnaeus informs us, in the Swedifh 
 Tranfadlions for the year 1742, that the 
 true Archel Mofs is to be found on the 
 weftern coafts of England ; andfufpedls, that 
 there are feveral other more common Moffes, 
 from which valuable colours might be ex- 
 trailed : A quantity of Sea-mofs having rot- 
 ted in heaps upon the Ihore, he obfervea the 
 liquor in the heaps to look like blood, the 
 fea-water, and the fun, and the putrefaction 
 having brought out the colour. Mr. Kalm, 
 in an appendix to Linnaeus’s paper in tha- 
 year 1745, mentions two forts of Moffes 
 actually employed in fome parts of Sweden 
 for dying woollen red : One is the Liche- 
 noides coralliforme apicibus coccineis of Ray’s Sy- 
 nopfis ; the other, the Lichenoides tartareum 
 farinaceum , fcuteliarum umbone fufco of Diile- 
 nius. This laft is a white fubftance, like 
 meal clotted together, found on the fides 
 and tops of hills. It is fhaved off from the 
 rocks after rain, purified from the ftony 
 matters intermixed among it by wafhing 
 with water, then dried in the fun, ground in 
 mills, and again wafhed and dried : It is 
 then put into a veffel with Urine, and fet by 
 for a month : A little of this tincture added 
 to boiling water makes the dying liquor — 
 In the fame Tranfactions, for the year 
 1754, there is an account of another Mofs, 
 which prepared with Urine, gives a beauti- 
 ful and durable red or violet dye to Wool 
 and Silk. This is the Lichen foliaceus, urnbi- 
 licatns , fubtus lacunofus Linn. flor. fuec. It 
 grows upon rocks, and is readily diftin- 
 guifhed from others of that clafs, by its 
 
 looking as if burnt or parched, confining of M O S S E s. 
 leaves as thin as paper, convex all over on <_ — j 
 the upper fide, with correfponding cavities 
 underneath, adhering firmly to the Hones by 
 a little root under the leaves, and coming 
 afunder, when dry, as foon as touched. It 
 is gathered after rain, as it then holds beft 
 together, and parts eafieft from the Hone. 
 
 In France, a cruflaceous Mofs, growing 
 upon rocks in Auvergne, is prepared with 
 Lime and Urine, and employed by the dyers 
 as a fuccedaneum to the Canary Archil, to 
 which it is Laid to be very little inferior : It 
 is called OrJ'eille dd Auvergne or Perelle. Mr. 
 
 Hellot relates, that he has met with feveral 
 other Moffes, which on being prepared in 
 the fame manner acquire the fame colour. 
 
 The moft expeditious way, he fays, of try- 
 ing whether any Mofs will yield an Archil 
 or not, is, to moiflen a little of it with a 
 mixture of equal parts of Spirit of Sal am- 
 moniac and ftrong Lime-water, and add a 
 fmall proportion of crude Sal ammoniac : 
 
 The glafs is then to be tied over with a 
 piece of bladder, and fet by for three or four 
 days. It the Mofs is of the proper kind, 
 the little liquor, which runs from it upon 
 inclining the veffel, will appear of a deep 
 crimfon colour; and this afterwards evapo- 
 rating, the plant itfelf acquires the fame 
 colour. 
 
 I have tried a good number of the com- 
 mon Moffes, both of the cruftaceous and 
 foliaceous kind, and not a few of the fungi; 
 as alfo the herbs Camomile and Mil- 
 foil which yield a blue effential Oil, a*nd 
 T’hyme whole Oil becomes blue by dige- 
 llion with volatile fpirits ; but have not as 
 yet met with any that yielded a colour like 
 Archil. Moft of them gave a yellow or 
 reddifh-brown tincture and if there was a 
 fcarcity of other drugs for thefe kinds of 
 dyes, feme of the Moffes might be made to 
 afford not inelegant ones. A few gave a 
 deep red colour to the liquor ; but when di- 
 luted it fhewed a yellowifn caft, and when 
 applied on cloth it gave only a ydlowifh 
 red. 
 
 SECT, 
 
[ 44 ° ] 
 
 SECT. 
 
 IV. 
 
 Artificial productions from Vegetables. 
 
 Artifici&l 
 
 Products. 
 
 I N the foregoing feCtions we have endeavoured to inveftigate the internal 
 conftitution of vegetables in their natural ftate, by operations which do 
 not alter their qualities ; todifcover, extraCt, and preferve thofe principles 
 which actually exift in them, and in which their fpecific powers refide. It has 
 formerly been obferved, that thefe principles are far from being elementary 
 bodies. By fermentation, and by the force of fire, the Gums, the Refins, the 
 Oils, and the Salts of vegetables, are refolved or converted into more fimple 
 parts, and fome of thefe combined varioufly together again into new com- 
 pounds: The tafte, the fmell, the colour of the original vegetable are de- 
 ftroyed, and fubftances of entirely different qualities are produced. 
 
 Fermenta- 
 
 Vinous. 
 
 Acetous.. 
 
 Putrefactive. 
 
 Obfervations 
 on its three 
 Sages. 
 
 CLASS I. 
 
 Products from Vegetables by Fermentation. 
 
 S WEET vegetable juices or infufions made in water, however bright pel- 
 lucid and apparently homogene, on being kept in a temperately warm 
 place in veffels not clolely ftopt, become turbid, conceive an inteftine motion, 
 emit numerous air bubbles, and difcharge a pungent vapour of extreme fubti- 
 lity and activity, infomuch as, when confined and accumulated in clofe rooms, 
 to extinguifb fire and fuffocate animals : Its producing the firft of thefe effects, 
 is a mark that it is collected in fufficient quantity to produce the other : When 
 candles continue to burn, we need not be afraid that this wild Gas, as Elelmont 
 calls it, will be dangerous to life. As the fermentation advances, a large 
 quantity of grofs, unCtuous,. faline and earthy matter is feparated and thrown 
 off, partly to the furface, and partly to the bottom of the veflel : The liquor 
 lofes its fvveet tafte and acquires a vinous one, and on being now committed to 
 diftillation yields, not as at firft a mere watery phlegm, but an inflammable 
 inebriating fpirit On continuing the fermentation beyond the ftate of vi- 
 nofity, more matter is thrown off, new combinations take place, tfte in- 
 flammable fpirit is deftroyed, and the liquor becomes four If the procefs 
 
 be ftill further protraCted, the acid ftate .is fucceeded by a putrefactive one ; 
 during which a volatile alcaiine Salt is both generated and difiipated : The folid 
 matter that now remains is an earth llmilar to common mould ; and if any 
 fluid is left, it is found to be an infipid water. 
 
 Fermentation is hence divided, according to its efteCt, into three ftages or 
 degrees, vinous, acetous, and putrefactive : The product of the firft is an in- 
 flammable fpirit, and of the lecond an acid, both of which are peculiar to the 
 
 vegetable 
 
Artificial Vegetable Productions* 
 
 vegetable kingdom : The volatile alcali, produced by the third ftage, is fmii- Fer-menta- 
 Jar to that obtained, more plentifully, from animal fubftances by the adtion of TI0N ” 
 fire without putrefaction. The putrefactive ftage always follows the vinous 
 and acetous, unlefs prevented by art, but it is not always preceded by them, 
 all vegetables being fufceptible of putrefadtion, whilft thofe only that have a 
 manifeft fweetnefs are capable of yielding a vinous liquor. The lweeter and 
 richer the vegetable juice, the longer does the vinous fermentation continue, 
 and the Wronger and more fpirituous is the Wine : The more acid alfo .is the 
 Vinegar. 
 
 Is is obfervable that when fweet juices are boiled down to a thick con fiftence, Impeded and 
 they not only do not ferment in that (late, but are not ealily brought into fer- promoted* 
 mentation when diluted with as much water as they had loft in the evapora- 
 tion, or even with the very individual water that had exhaled from them. 
 
 Juices and decodtions in general, that have fuffered much fire, however fweet, 
 are little difpofed to ferment. Hence fundry fweet liquors, naturally very pro- 
 penfe to run into this procefs, and to run haftily through all its ftages, are 
 preferved for a length of time by being boiled. 
 
 The head which forms on the furface of fermenting liquors greatly haftens 
 the fermentation of others, and determines them to the fame fpecies of fermen- 
 tation with that of the liquor from which the ferment was taken. The grand 
 promoters of all the ftages of this procefs are, warmth, a moderate admifiion 
 of air, and the addition of matters in an actually fermentative ftate. When 
 the vinous ftage is completed, the acetous would foon begin, if the liquor 
 was not racked into frefli vefiels, fecured from the air, and kept in a cold 
 place. 
 
 I. WINES. 
 
 nr HE juices of fweet fruits in general, Currants, Mulberries, Rafpberries, Wine s.' 
 A Apples, Pears, &c. are called, when fermented. Wines; but the name is > 
 more peculiarly applied to the fermented juice of the Grape or the fruit of the 
 Vine-tree, 
 
 There is a great variety of Grapes, colourlefs, yellowifh, bluifn, and red ; 
 more or lets fweet, and of more or lefs flavour. The colour is lodged not in 
 the juice but in the fkinof the Grape : The juice however, as a menltruum, 
 frequently extradts and becomes impregnated with it during its expreflion from 
 the fruit. 
 
 One and the fame kind of Grape proves greatly different in tafte and fla- Differences in 
 vour, according to the climate and expofure to the fun. In cold countries the Gra P es n 
 Vine, if it grows at all, never ripens its fruit ; and even in France and Italy J clima£e > dfo 
 have obferved, that the Grapes produced on the South-fides of hills are notably 
 fweeter than thofe which grow on plane grounds. Among the Tockay Wine- 
 hills, there is but one which directly fronts the South, and the advantages of 
 its fituation are not a little remarkable: From the extraordinary fweetnefs of 
 its Grapes, it is called the Sugar-hill. It affords the moft delicious of all the 
 Hungarian Wines, and is appropriated to the ufe. of the imperial family. 
 
442 
 
 Wines. 
 
 Mud, its dif- 
 ferences ; 
 
 enriched. 
 
 Arrangement 
 of Wines ac- 
 cording to 
 their produc- 
 tion. 
 
 Artificial Vegetable ProduSlions. 
 
 In very warm dry feafons, the Grapes at the bottoms of the hills are bed ; 
 in warm and moid ones, thofe at the top; fuch as grow in the middle region 
 being always good. In dry fummers, the Grapes are fweeted, but lead: juicy : 
 In rainy ones they abound with juice, which proves proportionably weaker and 
 more dilute. Frofts in autumn promote their ripening; but frod fucceeding 
 heavy rains make them apt to burft and died their juice. 
 
 In fome places, the Grape is concentrated or rendered richer, by fuffering it 
 to remain on the tree till great part of its watery moidure has exhaled, the 
 Hem of each duller being cut half through, when the fruit is ripe, to prevent 
 the afHux of any frefh juice from the plant. The fweet Hungarian and Spanifh 
 Wines are made from Grapes that have thus been half dried. The Raifins, 
 and Currants of the fhops, are different fpecies of Grapes, dried either in 
 this manner, or by the folar or culinary heat after gathering. 
 
 The juice of the Grape is called, before its fermentation, Mud. Different 
 forts of Mud are obtained from the fame kind of Grape, produced in the fame 
 vineyard, according to the method of management. The bed is that which 
 iffues upon breaking, bruifing, or treading the picked fruit: Inferior forts are 
 extracted by forcibly preffing the entire cluder, dalks and all. Dilute watery 
 Muds are enriched by infilling in them dried Grapes, or by infpiffating a part 
 of the liquor and adding this to the red. By thefe means drong full-bodied 
 Wines are obtainable from the poored juices; and by dmilar managements 
 even the better forts of Grape-wines are imitable with the juices of other fruits, 
 artificially concentrated, or heightened with the fimple fweetnefs of Sugar. 
 
 Wine may be divided, with refpedl to the fermentation, into three claffes. 
 (i/) Thofe of the fird do net indeed deferve the name of Wines, as having 
 fcarcely differed any degree of fermentation at all, and being no other than 
 boiled Mud. Several of the Italian Wines are of this fort, and are called by 
 the general name of Vino cotto or boiled Wine. It is to thin watery juices, ex- 
 tremely prone to ferment, and in which fermentation, when once begun, can 
 fcarcely be fuppreffed till it has run beyond the vinous date, that this procefs is 
 applied : By boiling, the fermentative quality is redrained, and the liquor be- 
 comes richer and continues fit for drinking for at lead a year or two, though 
 it is never fo wholfome as the fermented Wines. The effedls of Mud and 
 Wine upon animal bodies are diametrically different: Mud relaxes and lique- 
 fies, and if drank immoderately, is apt to produce dangerous fluxes: Perfedt 
 
 Wine, on the contrary, corroborates and condringes. (2.) The fecond clafs 
 comprehends thofe Wines, which have undergone fermentation, but not a 
 complete one: Of thefe there are two kinds. The fird is the thin fweet 
 
 Wines; which are no other than Mud partially fermented, or whofe fermen- 
 tation is checked, while it can be checked, before the fweetnefs has gone off: 
 Thefe Wines can fcarcely be kept above a year : Such are the Tyrol, fome of 
 the Savoy, and feveral of the Italian. The fecond fort is the drong, full- 
 bodied, rich, fweet Wines, which are generally a mixture of fermented and in- 
 fpiffated Mud ; the latter being added to increafe the richnefs of the liquor, and 
 prevent the fermentation from running beyond its due limits: Thefe kinds of 
 Wines greatly heat the conditution, and ought to be very fparingly drank : 
 Such are Malm fey, Canary, and fome of the Spanifh and Hungarian Wines. 
 
 5 (30 To 
 
Artificial Vegetable ProditSHons. 
 
 443 
 
 (3.) To the third clafs belong thofe Wines which have been completely fer- W 1 n' e s„ 
 mented, and have thrown off their grofs matter. Thefe are the molt perfebt y— « 
 Wines, and for common ufethe molt wholfome. 
 
 The principal Wines drank in Europe are as follows. ( 1 .) The Madera Account of 
 iflands, and Palma one of the Canaries, afford two kinds ; the firft called Ma- the principal 
 dera Sec the latter, which is the richelt and belt of the two, Canary or Palm Wl " es ol ^ u ‘ 
 Sec. The name Sec (corruptly written Sack,) fignifies dry ; thefe Wines being 
 made from hall dried Grapes. There is another fort of Sec Wine, inferior to 
 both the foregoing, prepared about Xeres in Spain, and hence called, accord- 
 ing to our orthography, Sherris or Sherry. (2.) The Wines of Candia and 
 Greece, particularly the latter, are of common ufe in Italy. Malmfey was for- 
 merly the produce of thofe parts only, but is now brought chiefly from Spain : 
 
 It is a fweet Wine, of a golden or brownifh-yellaw colour : The Italians call it 
 Manna alia bocca e baljamo al cervello , “ Manna to the mouth and balfam to the 
 4 ‘ brain.” Zant and Cephalonia fend alfo to Venice fame good, and no fma.ll 
 quantity of indifferent Wines : Almoft all the Wines indeed made ufe oi in the 
 Venetian territories come from Greece and the Morea; of which there are fome 
 forts fo bad, and fo cheap, that large quantities are made into Vinegar for the 
 preparation ol Ceruffe. (3.) Italy, not Greece, produces the Vino Greco : This 
 is a gold-coloured unbtuous Wine, of a pungent fweetnefs, the growth of 
 Mount Vefuvius, greatly fophifticated by the Neapolitans. In the neighbour- 
 hood ofVefuvius is made the Mangiaguerra Wine, as alfo a thick blackilh one 
 called Verracia •, and at the foot of the hill, the delicious Vino vergine : The Ita- 
 lians apply this laft name likewife to all the other Wines made without preffure. 
 
 The kingdom of Naples affords the Campania or Pauftlippo and Mufcatel , the 
 Surentine , Salernitan , and other excellent Wines, as alfo the Chiarello , much 
 drank at Rome. But the principal of all thefe Wines is the red, far, fweet, 
 and gratefully poignant one, called LachrymaChrijli. (4.) The ecclefiaftical 
 ftate produces the light, pleafant Albano ; and the fweet Mcntefiafcone , a yel- 
 lowifh not very ftrongWine, which comes the neareft to good Florence, but 
 does not keep well ; together with feveral of lefs note, as the Nomentan , Monte- 
 ran , Velitrin , Pr<enetic , II Romanefca, d'Orvieto, &c. ( 5 . ) In Tulcany are the 
 
 excellent white and red Florence \ the celebrated, hot, ftrong red Wine de Monte 
 Pulciano ; the Montalneo , Porte Hercole , &c. But along the coaft of the Adriatic, 
 at Ancona, Rimini, Pefaro, as far as Bologna, I met with exceeding bad Wines, 
 chiefly of the boiled unfermented kind, heavy, difagreeable, and unwholfome. 
 
 (6.) In Lombardy alfo there is abundance of bad Wines : The Mcdenefe and 
 Montjerrat are tolerable; the Marcemino, produced about Vicenza and Padua, 
 pretty good. The other Wines, mofl commonly drank in that province, are 
 the Brefcian, Vercnefe, Placentine, Lumelline , and Pucine ; and in the Genoefe, 
 the Vino di monte vernaccia , Vino amabile or Vino di cinque terre and Vino razzefe. 
 
 Between Nizza and Savona is produced an incomparable Mujcadine ; near A- 
 quileia is thtRofatz, and near Pavia the Vino piccante. (7.)Piemont and part 
 of Savoy haveexcellent light Wines. (8.) The Sicilian, Sardinian and Corfican 
 Wines are alfo good : The flrft, as particularly the Catanean , Pancrmitan , Mef- 
 finian , and Syracufan, are accounted the bell, and are chiefly bought up by the 
 Knights of Malta. (9.) Mofl of the Spanifh Wines are compofed of fermented 
 
 L 1 1 2 or 
 
444 Artificial Vegetable Produ&ions , 
 
 W i n e s, or half fermented Wine mixed with infpiffated Muft and varioufly manufac- 
 
 v — — — f tured, or of an infufion of dry Grapes in weak Muft. No Wines freeze more 
 difficultly than the Spaniffi, thefe abounding both with undluous matter and 
 with inflammable fpirit. We have a few of thefe Wines in Germany, as the 
 Alicant (which is a thick, ftrong, very fweet, and almoft naufeous Wine,) 
 Sherry, SpaniJJj Malmfey, and that Amply called Spanijh Wine : But in Spain itfelf 
 there are many more, ' Tarragan , Salamanca , Malaga, Cordoua, Galicia , Anda- 
 lufia, iundry baftards, Vino de toro , &c. (io.) In Portugal there is plenty of 
 
 red Port, a cheap but not a very excellent Wine, drank in large quantity in 
 England. The bed Vino tinto , a blackifh red Wineufed by the coopers for co- 
 louring other Wines, is faid by fome to be the produce of Portugal. This 
 kingdom deals largely alfo in Madera, of which the King receives yearly twelve 
 thoufand pipes by way of tithes, (n.) In France, there is a great variety of 
 Wines ; of which the ftrong, fweet, full-bodied, fpirituous ones are called Vins 
 de liqueur. There is fcarcely a province in France that does not produce Wine : 
 Languedoc and Provence afford the fweeteft ; and the fame provinces, with 
 Champagne and Burgundy, the ftrongeft : The Wines of the Northern parts, 
 as Picardy and Bourdeaux, are theworft; and thofe about the middle of the 
 kingdom, as Paris and Orleans, of a middling kind. The moft celebrated of 
 the French Wines are, Champagne, Burgundy, Vin de Beaune or Partridge-eye, 
 Cote roti , St. Laurence, Front iniac, Mujcat de Lion, Cahors , Hermitage , Grave, Vin 
 dd Llaye, &c. (12.) In Switzerland, the belt are the Neufchatel, Velteline , Lacote 
 
 and Reiff Wine : The Velteline Straw-wine, fo called from the Grapes being laid 
 for fome time upon ftraw before they are preffed, is particularly celebrated. 
 (13.) The dry-grape Wines of the Upper Hungary are in general excellent, 
 and greatly fuperior to thofe of the Lower. They have a delicious aromatic 
 fmell andtafte, a notably diaphoretic and corroborating virtue, and when drank 
 freely occafion no headach, heavinels of the limbs, or other inconveniencies : 
 They donoteafily become vinewed even in open veffels ; and retain their fweet- 
 nefs and agreeablenefs for a length of time, though they lofe a little from year 
 to year. (14.) Among the German Wines, the Tyrol are very delicate, parti- 
 cularly thofe ofTramin and Etfch, but they do not keep. (15.) Good Auftrian 
 Wine is not to be rejected. Thofe of Klofter-Neuburg and Brofenberg are 
 accounted the beft, and feemed to me to excel in tafte that ofEdenburg in 
 Lower Hungary. There are alfo good Wines in feveral other parts of the im- 
 perial dominions. ( 16.) In the Palatinate, the beft Wine is that of Worms, 
 efpecially the fort called Women’s Milk; and next to this, thofe of Eding- 
 hof and Am bach. (17.) Among the more efteemed German Wines are to be 
 reckoned alfo Rhenijh, Mayne, Mofelle, Netkar and Elfafs : A certain writer calls 
 the Rheniffi made in Hochheim [Hock] the Prince of the Wines of Germany. 
 
 ( 1 3 .) The Bohemian, Silefian, Thuringian, Mifnian, Naumberg, Branden- 
 burg, and other German Wines, are greatly inferior to the foregoing : Some 
 however, of thofe of Mifnia and the Marche, made from ripe picked Grapes, 
 have this advantage, that they are greatly meliorated by age, fo as to be pre- 
 ferred by many to the Rhenilh, Neckar and Franconia Wines, and frequently 
 mixed with others of greater note. The tartifli German Wines keep the 
 
 longeft 
 
Artificial V tgetable ProduSlions. 44 ^ 
 
 longeft of any : Some of them have been kept for two or three hundred years ;Wines. 
 and in Strafburg there is a calk fourteen hundred years old, and many above 
 feventy ; the Wine being occasionally racked off into Smaller and Smaller calks, ° bl ’ erva J ;ions 
 that the veflfel may be conftantly full. Thefe very old Wines are prelerved 0 fVhnew 
 rather for curiofity than uSe, as they not only grow too ftrong for drink- 
 ing, but at lalt quite difagreeable. The beft are thoSe of a middle age, from 
 twenty to about fifty years. 
 
 Wine fenfibly waftes in keeping, howclofely Soever the calk is ftopt, a pare 
 tranfpiring through the pores of the wood : It is not the Spirituous, but the 
 watery part that is thus loll, for the remaining Wine proves ftroriger than at 
 firfi, and the ftrength continues to increafe as the quantity diminilhes. In 
 filling up the velfels, for it is neceffary they fhould be kept fullj we muft be 
 careful not to mix Wines of dilSimilar qualities : The Hungarian does not well 
 bear any other Wine, particularly Rhenifh : If the Spontaneous diminution of 
 a calk of Hungarian is made up with Rhenifh, though both keep extremely 
 well by themfelves, the mixture prefently Spoils. Cool cellars are of primary 
 confequence for the prefervation of Wines : It is owing wholly to want of fuffi- 
 cient defence from the warmth of the weather that Wines are fo apt to fret or 
 run into a new fermentation on the approach of Summer. The Situation of 
 Berlin does not admit of deep cellars. I have been in Some at Vienna three 
 ftories deep: The cellar of the Jefuit’s college Seemed to be not lefs than the 
 height of a church fteeple under the Street. It is necelfary, for the preserva- 
 tion of Some Wines, to fumigate the calks with burning Brimftone, to which 
 Some add, perhaps ufelefsly, vinous Spirits and aromatic ingredients : The fumes 
 of Brimftone ftrongly refill fermentation, but Wines that are largely impreg- 
 nated with them cannot be recommended as wholfome : The colour of red 
 Wines is deftroyed by them. What is called Slum, is no other than Muft 
 whofe fermentation has been prevented, or prematurely SupprdSed, by fumi- 
 gation with Sulphur. 
 
 The colours of Wines are frequently artificial. A pale yellow may be natu- Colouring of 
 ral, but a fine deep yellow proceeds from an addition of burnt Sugar or other Wines, 
 colouring matters, or from the oaken calks : Wines may be naturally of a pale 
 dilute red, but a deep red is almoft always the efifedt of artificial additions, as 
 the red woods. Bilberries,- &c. In France, no Secret is made of thefe practices, 
 the colouring matters, after they have been ufed, being publickly thrown out. 
 
 Turbid Wines are fined by a mixture of whites of eggs, powdered Alabafter Curation, fla- 
 and Fifh-glue ; Some ufe the plant Lycopodium : Acid ones are cured by an ad- vouring, 
 dition of Salt ofTartar orabforbent earths, in Such quantity as to abforb and 
 neutralize only the redundant acid, and not that which is effential to the 
 Wine, for in this cafe the liquor would Soon become vapid : Weak Wines are 
 improved by an addition of Spirit, particularly before the fermentation is com- 
 pleted, for after this period it is apt to Spoil the vinofity : Poor Wines are en- 
 riched by Sweets, and flavoured by various additions fo as to emulate the more 
 coftly : Thus Elder-flowers give the flavour of Mofelle : Even the more deli- 
 cious Wines have been imitated alfo without a drop of the juice of any kind of 
 Grape ^ with Solutions of Sugar, juice of Currants, Figs, and other fruits. 
 
 Som§ 
 
446 Artificial Vegetable Productions, 
 
 Wines. Some of the dealers in Wines have had recourle to artifices of a more dange- 
 rous kind, which have been pernicious to thoufands : They have fweetened 
 Dangerous ac jd \\7j nes by Litharge or other preparations of Lead * and impregnated fweet 
 oils of Wines ones Mercury-fublimate and with Arfenic. Lead is difcovered in Wines 
 difcovered. by adding a decoclion of Orpiment made in Lime-water: ' If the Wine is ge- 
 nuine, it does not fenfibly change its colour on this addition, though on Hand- 
 ing, a vellowifh-white powder falls to the bottom : It it has any faturnine im- 
 pregnation, its colour becomes immediately darker, brown, reddifh, or biackilh. 
 Arfenic may be detedled by a folution of Lead in Aqua fortis * and Mercury - 
 fublimate, by volatile alcaline fpirits, or by a folution of fixed alcaline Salts. 
 Characters of The goodnefs and wholfomenefs of Wines are judged, from their being 
 good Wine, bright, clear, and fparlding in the glafs * of an agreeable reviving fmell and 
 tafte •, leaving, when held in the mouth for fome time, a flight fenle of afirin- 
 gency * being moderately Hrong and fpirituous * paffing freely by urine* ex- 
 citing appetite* producing a gentle fweat in the night* keeping the belly open 
 next day * without being followed by any headach, heavinefs of the limbs, or 
 other uneafinefs. Such a Wine, moderately ufed, is a very valuable cordial. 
 The fweet rich Wines are either new, or very Hrong and fiery : They heat the 
 blood much more, and if drank to any degree of excefs, their effects continue 
 much longer than thofe of the thinner Wines that contain an equal quantity of 
 fpirit. The red Wines in general have the greateft aflringency. 
 
 Chemical The principles of which Wines confiH are, (i.) Water, the bafisof all fluids * 
 analyfts. (2.) inflammable fpirit * (3.) a fine faline matter, which ariles in diftillation 
 immediately after the fpirit, called by Becher Media fubjlantia vini * (4.) A 
 grofferSalt called Tartar, which in part feparates on Handing and adheres to 
 the fides of the calk in folid mafles * (5.) A gummy or mucilaginous fub- 
 ftance, and (6.) a grofs undtuous or refinous one. The following table exhi- 
 bits the quantity of thefeveral principles in a quart of each of the Wines I have 
 examined. 
 
 Aland 
 
Artificial Vegetable Produ&ions . 
 
 447 
 
 Wines, 
 
 
 Highly recti- 
 fied lpirit. 
 
 Thick, oily, 
 undtous, refi- 
 nous matter. 
 
 Gummy and 
 tartareous 
 matter. 
 
 Water, 
 
 
 oz. dr. 
 
 err 
 £>* • 
 
 oz. 
 
 dr. 
 
 g r - 
 
 OZ 
 
 . dr. 
 
 g r 
 
 lb. 
 
 OZ. 
 
 dr. 
 
 g r - 
 
 Aland - 
 
 i 
 
 6 
 
 oo 
 
 3 
 
 2 
 
 oc 
 
 l 
 
 5 
 
 oc 
 
 2 
 
 5 
 
 3 
 
 oo 
 
 Alicant - - 
 
 3 
 
 6 
 
 oo 
 
 6 
 
 o 
 
 20 
 
 o 
 
 i 
 
 4 c 
 
 2 
 
 2 
 
 6 
 
 oo 
 
 Burgundy - 
 
 2 
 
 2 
 
 oo 
 
 o 
 
 4 
 
 OO 
 
 o 
 
 i 
 
 40 
 
 2 
 
 9 
 
 o 
 
 20 
 
 Carcaffone - - 
 
 2 
 
 6 
 
 00 
 
 0 
 
 4 
 
 10 
 
 0 
 
 i 
 
 20 
 
 2 
 
 8 
 
 4 
 
 30 
 
 Champagne - 
 
 2 
 
 5 
 
 20 
 
 o 
 
 6 
 
 40 
 
 o 
 
 i 
 
 00 
 
 2 
 
 8 
 
 3 
 
 OO 
 
 French - 
 
 3 
 
 o 
 
 00 
 
 o 
 
 6 
 
 40 
 
 o 
 
 i 
 
 OO 
 
 7 
 
 8 
 
 o 
 
 20 
 
 Frontignac - - 
 
 3 
 
 o 
 
 oo 
 
 ■3 
 
 4 
 
 oo 
 
 o 
 
 5 
 
 2 0 
 
 j 
 
 4 
 
 6 
 
 3 ° 
 
 Vin Grave 
 
 2 
 
 o 
 
 oo 
 
 0 
 
 6 
 
 oo 
 
 o 
 
 2 
 
 00 
 
 2 
 
 9 
 
 o 
 
 00 
 
 Hermitage - 
 
 ,2 
 
 7 
 
 oo 
 
 I 
 
 2 
 
 oo 
 
 0 
 
 I 
 
 4 ° 
 
 2 
 
 7 
 
 5 
 
 20 
 
 Madera - 
 
 2 
 
 3 
 
 oo 
 
 3 
 
 2 
 
 oo 
 
 2 
 
 O 
 
 oo 
 
 2 
 
 4 
 
 3 
 
 00 
 
 Malmfey - - - 
 
 4 
 
 o 
 
 oo 
 
 4 
 
 3 
 
 oo 
 
 2 
 
 3 
 
 OC 
 
 2 
 
 i 
 
 2 
 
 00 
 
 Vinode Monte Pulciano 
 
 2 
 
 6 
 
 oo 
 
 o 
 
 3 
 
 oo 
 
 o 
 
 2 
 
 40 
 
 2 
 
 8 
 
 o 
 
 20 
 
 Mofelle - - 
 
 Z 
 
 2 
 
 oo 
 
 o 
 
 4 
 
 20 
 
 O 
 
 I 
 
 3 ° 
 
 2 
 
 9 
 
 o 
 
 10 
 
 Mufcadine - - 
 
 3 
 
 O 
 
 oo 
 
 2 
 
 4 
 
 oo 
 
 I 
 
 0 
 
 oo 
 
 2 
 
 5 
 
 4 
 
 00 1 
 
 Neufschatel - - - 
 
 3 
 
 2 
 
 oo 
 
 4 
 
 o 
 
 oo 
 
 I 
 
 7 
 
 oo 
 
 2 
 
 2 
 
 7 
 
 00 
 
 Palm Sec - 
 
 2 
 
 3 
 
 oo 
 
 2 
 
 4 
 
 oo 
 
 4 
 
 4 
 
 oo 
 
 2- 
 
 2 
 
 5 
 
 00 
 
 Pontack - 
 
 2 
 
 o 
 
 oo 
 
 O 
 
 5 
 
 20 
 
 o 
 
 2 
 
 oo 
 
 2 
 
 9 
 
 o 
 
 40; 
 
 Old Rhenifh - - 
 
 2 
 
 o 
 
 oo 
 
 r 
 
 o 
 
 00 
 
 o 
 
 2 
 
 20 
 
 2 
 
 8 
 
 5 
 
 40 
 
 Rhenilh - 
 
 2 
 
 2 
 
 oo 
 
 o 
 
 3 
 
 20 
 
 o 
 
 I 
 
 34 
 
 2 
 
 9 
 
 i 
 
 06 
 
 Salamanca » 
 
 3 : 
 
 o 
 
 oo 
 
 3 
 
 4 
 
 OO 
 
 2 
 
 O 
 
 oo 
 
 2 
 
 3 
 
 4 
 
 00 1 
 
 Sherry - 
 
 3 
 
 o 
 
 oo 
 
 6 
 
 o 
 
 OO 
 
 2 
 
 2 
 
 oo 
 
 2 
 
 o 
 
 6 
 
 00 j 
 
 Spanifn 
 
 i 
 
 2 
 
 oo 
 
 2 
 
 4 
 
 oo 
 
 9 
 
 4 
 
 oo 
 
 I 
 
 IO 
 
 6 
 
 00 
 
 Vino Tinto - - - 
 
 3 
 
 Q 
 
 oo 
 
 6 
 
 4 
 
 oo 
 
 i 
 
 6 
 
 oo 
 
 2 
 
 o 
 
 6 
 
 00 
 
 Tockay - - - 
 
 z 
 
 2 
 
 oo 
 
 4 
 
 3 
 
 oo 
 
 5 
 
 o 
 
 oo 
 
 2 
 
 o 
 
 3 
 
 00. : 
 
 Tyrol red Wine 
 
 i 
 
 4 
 
 oo 
 
 i 
 
 2 
 
 oo 
 
 o 
 
 4 
 
 oo 
 
 2 
 
 8 
 
 6 
 
 00 
 
 Red Wine - - - 
 
 i 
 
 6 
 
 oo 
 
 o 
 
 4 
 
 40 
 
 o 
 
 2 
 
 oo 
 
 2 
 
 9 
 
 3 
 
 20 
 
 White - - 
 
 2 
 
 o 
 
 oo 
 
 o 
 
 7 
 
 oo 
 
 o 
 
 3 
 
 oo 
 
 2 
 
 7 
 
 o 
 
 OO 
 
 Table of the 
 contents of 
 different 
 Wines. 
 
 From thefe experiments it appears that the red Wines of our own country 
 [the Marche of Brandenburg] contain moft water, Malmfey moft fpirit. 
 
 Vino Tinto moft undtuous matter, and Spanifh the moft gummy and faline 
 matter; that this laft holds the leaft water and the leaft fpirit, Champagne the 
 lead Tartar and Mucilage, and ordinary Rhenifh the leaft undluous matter. 
 
 When once the principles of Wine arp leparated from one another, no art ^] tere j iITe 
 can reproduce Wine by joining them together again : When barely the inflam-coverably, by 
 triable fpirit has been diftilled off, the addition of that fpirit to the refiduum thefeparation 
 does not reftore its vinofity : The refiduum itfelf often buffers a new feparation of . an f 
 upon this addition, its tartareous parts precipitating. pnncip es. 
 
 When Wines are expofed to the adtion of a freezing air, a part of their water congelation, 
 congeals, and the unfrozen part proves proportionably ftronger and more fpi- 
 situous : By repetitions of this proceis, firft pointed out by Paracelfus and fince 
 
 carried 
 
44-S 
 
 Artificial V egetable Productions. 
 
 W i n e s. carried to a greater length by Stahl, the bell Wines are reduced to about one 
 fixth of their original volume. Wines thus concentrated or freed from their 
 redundant phlegm, are no longer the delicate liquors they were before : They 
 are too unpleafant, as well as too ftrong, to be drank by tnemfelves, and when 
 mixed with other Wines, communicate to them alfo a difagreeable taint. The 
 phlegm which congeals retains a part of the truly vinous matter, as appears 
 from its being convertible into Vinegar \ but this phlegm, mixed with the un- 
 frozen Wine, does not reftore its priftine qualities : Both the phlegm by itfelf, 
 and the mixture, foon corrupt. 
 
 Malt 
 
 Liquors. 
 
 V — —> 
 
 Subjects of 
 -vinous fer- 
 mentation. 
 Malt. 
 
 MALT L I Q_U O R S. 
 
 gWEET vegetable liquors are the only ones difpofed to vinous fermenta- 
 tion. The feveral kinds of grain, as Barley, Wheat, Rye, Oats, Buck- 
 wheat, &c. and the feeds of leguminous plants, as Peas, Tares, Lentils, &c. 
 when they begin to vegetate, are remarkably fweet; and in this Rate, called 
 Malt, they readily communicate their fermentable fweetnefs to boiling water. 
 
 Malt is prepared chiefly from Barley, by fteeping it in water till it foftens 
 and fwells, and then laying it in heaps till it begins to fprout : When this hap- 
 pens, the vegetation is ftopt by fpreading it abroad thin, and afterwards com- 
 pletely drying it by the fun’s heat where that heat is fufficient, or in kilns 
 warmed by culinary fire: According as the heat is lefs or greater, the Malt it- 
 felf, and the tindlure which it gives to water, are of a paler or a browner co- 
 lour. Different forts of grain differ in their facility of vegetation : The fame 
 fort alfo vegetates fooner or later according as it is new or old. Hence 
 the impropriety of malting different forts, or one fort of different ages, toge- 
 ther: The procefs fhall be finifhed in one before it is begun in another ; fo 
 that either a part muff remain unmalted, or a part muff be overmalted : In 
 this laft cafe, the infufion of the compound is difpofed, according to the pro- 
 portion of the unmalted part, to an acid rather than a vinous fiate. 
 
 Differences of Infufions of Malt, or watery folutions of its fweet matter, have lefs pre- 
 ferments. penfity to fermentation than the juices of lweet fruits, and require always the 
 afliftance of yeaft or fome other adtual ferment. The quality of this ferment 
 greatly influences that of the liquor : Itfeems in fome meafure to afiimilate, as 
 it were, the whole mafs of liquor to its own nature, or to that of the liquor 
 from which it was taken. How different are the produ&s obtained from in- 
 fufions of the fame Malt, by ufing Yeafi of Beer, and the Yeaff or Lees of ge- 
 nerous Wine for a ferment! How fmall a portion of putrid Yeaft is fufficient 
 to fpread putrefaction through irnmenfe quantities of wort ! When waters 
 ufed for brewing have received an impregnation from the carcafes of animals, 
 though fo flight as not to be perceived in the water itfelf ; as foon as the li- 
 quor has been brought into fermentation, the putrid ferment has exerted its 
 
 Differences of activity, and difpofed the fermentation to its own kind Great differences 
 
 waters. are obferved in waters in regard to their fitnefs for brewing: It is remarkable, 
 that the waters of rivers, and of ftagnant ponds that are not putrid, though 
 quite muddy, and unfit for drinking, and even difguftful, produce better Beer 
 than thole of the fineft and moft limpid fprings. Perhaps it is their foftnefs 
 
 that 
 
Artificial Vegetable Productions. 449 
 
 that adapts them to this ufe, whilft their impurities are feparated in the courfe Malt 
 of the fermentation. Liquors. 
 
 Though infufions of Malt are of themfelves little difpofed to vinous fermen- — v • 
 
 tation ; when once that procefs has begun, they tend ftrongly to run beyond Fermentabl ' 
 it : In very hot weather, the fermentation can fcarcely be checked at the pe- lty ’ 
 riod of true vinofity. Hence Malt-liquor ; are moft fuccefsfully prepared in 
 the winter and fpring : And hence the warm climates can hardly make any 
 tolerable beer. 
 
 Thefe liquors are rendered much more durable, lefs apt to grow four, lefs Hops, 
 vifcid, and in general more w'nolefome, by the aromatic bitternefs of the Hop. 
 
 The hop contains a fubtile odorous principle, which promotes the effect of the 
 vinous fermentation : If infufed, or but lightly boiled in the wort, it fenfibJy 
 increafes the fpirituofity : If boiled for a longer time, its volatile principle is 
 diflipated, the beer proves bitterer, but receives no additional ftrength. 
 
 Sundry other fubftances have been employed for augmenting the inebriativelnebriative 
 power of malt-drinks, to the injury of their falubrity ; as Clary, Cocculus in- additions, 
 dus, and the plant called Bohemian-rofemary ( Cijlus ledon foliis rorifmarini fer- 
 rugineis C. B.) which laft produces a quick and a raving intoxication. Often- 
 times alfo different medicinal fubflances are added, with a view to render the 
 liquor ferviceable in particular difeafes. The adtive powers of many vegeta- Adivity of 
 bles are not only effectually extradled, but extended and multiplied as it were, vegetablesin- 
 by fermentation : So much pounded nutmeg as will lie on the point of a fement'n^ I* 
 
 knife, gives a flavour to a large vat of fermenting beer; whereas, when the- n *" 
 fermentation is finifhed, the quantity to which it gives a like impregnation, is 
 comparatively inconfiderable. 
 
 I have examined feveral of the German malt-liquors, both pale and brown, Contents of 
 in regard to their quantity of fpirit, the quantity of folid matter left upon in- d . ifferent Ma k 
 fpiffating them, and their degree of acidity, for they are all found, even in ll<luors “ 
 their founded: ftate, to be more or lefs acid : The acid principle cannot per- 
 haps be collected feparately, but it readily difcovers itfelf by neutralizing fixt 
 alcaline Salts. The ftrongefl: of the liquors I examined yielded, upon the 
 quart, ten drams of inflammable fpirit; and the weakefl: of thofe that are called 
 Strong-beers, five drams : Of common Table-beers, fome gave four and fome 
 three drams. The folid matter amounted in fome to near five ounces, in 
 others only to one ounce three drams ; in the Table-beers, to three ounces 
 and a half. The largeft quantity of fixed alcali, faturatcd by a quart, was 
 four drams thirty-four grains ; and the fmalleft, one dram twelve grains. 
 
 It is obfervable, that when Malt- liquors turn four, the bitternefs of the hop, 
 though ftrong before, is covered or over-powered by the acidity. It is not 
 however deftroyed : On adding an alcaline Salt or abforbent Earth, in l'uffi- 
 cient quantity to obtund the acid, the liquor taftes bitter again as at firfi. 
 
 Vinous 
 
 Spirits. 
 
 INFLAMMABLE SPIRITS. 
 
 INFLAMMABLE Spirits are extradted from fermented liquors by diftil- . 
 
 lation. As firfi: diftilled, they abound with phlegm, and contain lo m uc h ^hern^as 
 of the grols Oil of the fubjedt, that has not been attenuated or thrown off by diftilled. 
 
 M m m the 
 
45'0 Artificial Vegetable Preclusions,. 
 
 Vinous fhe fermentation, as to 'receive from thence particular flavours. Thofe drawn 
 Spirits, from Malt-liquors are in general naufeous-, thofe from Wines, more grateful. 
 
 ' — -v — The Brandies of France are all obtained from Wine, thofe of Germany from 
 Malt : In England, a fpirit is prepared from Malt for inferior ufes, and a 
 finer one from Melafles, or the fy.rupy matter which feparates in the making 
 or refining of Sugar : The rums of the American iflands are Iikewife the pro- 
 duce of the Sugar-cane (q). 
 
 Methods of There are different methods of eftimating the ftrength of thefe fpirits - 
 
 determining 1 Q n f} ia king a little in a vial, a number of bubbles rife upon the furface : 
 
 their ftrength. ^he more numerous the bubbles, and the more quickly they difappear, the 
 more fpirituous is the liquor. 2. If fome of the Spirit be poured upon Oil 
 
 Olive or Oil of Almonds, the Oil arifes to the furface, more or lefs haftily 
 
 according as the liquor contains more or lefs phlegm : In pure fpirit it does 
 not arife at all. 3. The hydrometer is a very convenient inffrument for deter- 
 mining the ftrength of thefe liquors : It confifts of a glafs ball with a flender 
 item divided into a number of equal parts, adjufted, in regard to weight, fo 
 as to link to a certain point in fpirit of a determined ftrength ; thofe fpirits, in 
 which it finks further or not fo far, are proportionably ftronger or weaker 
 than the ftandard. 4. Some fet the brandy on fire, and judge of its ftrength 
 from the quantity of phlegm or water that remains after the burning : Such as 
 leaves half its quantity is held to be of a fufficient ftrength for brandy, and 
 called proof. The phlegm thus freed from the fpirituous part, will readily 
 difeover by its tafte, how much or how little the brandy participated of nau- 
 feous matter ( r ). 
 
 Inflam- 
 
 ( q ) Spirit from Malt , &c.] Malted barley 
 affords the largeft quantity of Spirit, of any 
 kind of grain that has been tried, except 
 Rye, which is faid by fome to yield near 
 one third more. In the Swedilh tranfac- 
 tions, there are fome experiments of diftil- 
 ling a Spirit from potatoes. Sixteen mea- 
 fures of potatoes were boiled with Water, 
 and worked with the liquor till the whole 
 became a tough dough : This was diluted 
 with boiling water to the confiftence of thin 
 gruel, and fermented : The fermentation 
 went on well, and the liquor, diftilled on 
 the third day, yielded one meafure of good 
 Brandy. The potatoes did not fettle, or 
 burn to the {till, as might have been fuf- 
 petfted. The author, Mr. Skytte, makes 
 a comparifon, from this experiment, of the 
 profits in cultivating Potatoes and Barley for 
 the purpofes of diftillation : He computes, 
 that the produce of fpirit from Potatoes is to 
 that from Barley, in equal extents of ground, 
 as 566 to 156, even 'admitting the Potatoes 
 to be planted in the worft kinds of ground. 
 
 and the Barley in fo good a foil as to yield 
 an increafe of fifty fold. 
 
 (r) Methods of ejli mating the frength of fpi- 
 rits.'] Of all thefe methods, that by the hy- 
 drometer appears to be the moft accurate. 
 The hydrometer fhould be graduated for 
 this purpofe by marking the height to which 
 it finks in pure water, in pure fpirit, and in 
 mixtures of different proportions of the two; 
 for dividing theftem into a number of equal 
 parts betwixt the two extremes will not an- 
 fwer. It is the fpecific gravity of the liquor 
 that this inftrument meafures, and the fpe- 
 cific gravity of mixtures of water and fpirit 
 does not correfpond to the mean gravity of 
 the two ingredients. In thefe mixtures, as 
 in fundry metallic ones formerly mentioned, 
 there feems to be more than a bare juxta- 
 pofition of the particles of the two fluids ; a 
 part of one feems to be received within the 
 pores or vacuities of the other. If a certain 
 volume of pure water weighs 1000, the 
 fame volume of the pureft Abohol or moft 
 
 highly 
 
Artificial Vegetable Produ&iom. 451 
 
 Inflammable fpirits, perfectly purified from their phlegm and their grofs Vinous 
 Oil, are not found on any trial to differ or to be diftinguifhable from Spirits. 
 
 one another, whatever fubjebt they were produced from. The purification is v — * 
 
 effected by repeated diftillations in a gentle heat. Particular diftilling vefiels 
 have been contrived for this purpofe, of a fpiral form and an extraordinary fi ec p 
 height : Through thefe it was expedted that the lighter fpirit would arife pure, Reification, 
 leaving all the Water in its paifage. I have tried the celebrated ferpentine in the 
 royal elaboratory of Paris, but without the pretended fuccefs : The Water, by 
 a boiling heat, pafifed through every curvature and circumvolution of the in- 
 ffrument, along with the fpirit, and the diftilled fpirit was juft as phlegmatic 
 as if the common ftill had been ufed. This pompous and expenfive apparatus 
 has therefore no advantage above the common one ; the purity of the Spirit 
 from Water, depending in either cafe, folely upon the gentlenefs of the 
 fire. The fpirit, in its feparation from the phlegm, leaves alfo greateft part 
 of the naufeous oily matter behind, but oftentimes a part comes over with it : 
 
 If the diftilled Spirit be mixed with a quantity of pure Water, its Oil is extri- 
 cated by the Water, and on careful rediftillation it arifes pure from both. 
 
 Sundry additional matters have been employed for expediting the procefs by 
 abforbing and detaining the Oil and Phlegm ; as fixed alcaline Salts, Sea-falt, 
 Quick-lime, &c. Fixt alcalies anfwer the belt : By thefe, fpirits may be rec- 
 tified even without diftillation. If a quantity of pure and dry fixed alcaline 
 Salt be put into a phlegmatic Spirit, it imbibes the phlegm and the oily mat- 
 ter, and forms with them a thick ponderous liquid, which falls to the bottom, 
 and from which the Spirit may be eafily poured off : How ftrongly foever the 
 two liquors are fhaken together, they prefently feparate upon ftanding at reft. 
 
 Spirits thus rectified are not entirely pure : They contain fome fmall portion 
 of the alcali, fufficient to communicate a degree of pungency, that may render 
 them for fome purpofes unfit (s). 
 
 Spirit 
 
 highly rectified fpirit will weigh 820 ; the 
 fame volume of a mixture of equal parts of 
 the two will weigh, not the medium 910, 
 but nearly 925. If one meafure of water 
 and one meafure of fpirit be mixed together, 
 the quantity of the mixture will be very fen- 
 fibly lefs than two meafures. 
 
 From the rifing or finking of Oil in the 
 fpirit we can form only a grofs judgment of 
 what the hydrometer (if the liquor is brought 
 to an equal temperature in regard t© heat) 
 meafures with precifion. The quantity of 
 bubbles on the furface depends rather on the 
 oilinefs of the fpirit than on its itrength ; for 
 weak fpirits may be made to exhibit the 
 fame phaenomena in this refpeft as the 
 ftronger, by impregnating them with Oil : 
 From inattention to this circumftance, fome 
 of the workmen have been milled into an 
 opinion, that the fpirit proves ftronger when 
 
 the fire in the diftillation is kept to fuch a 
 height as to make the fpirit run in a full 
 ftream, than when a gentler fire is ufed ; a 
 ftrong heat forcing over more of the Oil, 
 and confequently making the fpirit aftume a 
 greater quantity of bubbles on being fhaken. 
 in regard to the quantity of water left on 
 burning, it depends more upon the manner 
 in which the fpirit is burnt than upon its 
 ftrength, as will appear hereafter. 
 
 (s) Part of the alcali retained by the fpirit.'] 
 
 A part of the alcali arifes alfo along with the 
 fpirit in diftillation, and communicates to it 
 what the workmen cal! an urinous flavour. 
 This may be prevented by adding an acid, 
 particularly the vitriolic, previous to the di- 
 ftillation ; the acid not only neutralizing the 
 alcaline Salt, but preventing it from arifing. 
 It would be imprudent to add the vitriolic 
 m 2 acid 
 
Criteria of 
 highly refti- 
 fied fpirit. 
 
 Analylis of 
 
 452 Artificial V egetable Produ&ions. 
 
 Vinous Spirit of Wine is the general name of rectified Spirits, whatever fubjed they 
 Spirits, were prepared from ; but is never applied to proof fpirits though drawn from 
 Wine itfelf. Spirits brought to the higheft degree of purity, both from phlegm 
 and Oil, are called Alcohol. By diluting redified fpirit with a fuitable quan- 
 tity of pure water, we obtain a pure and flavourlefs proof fpirit. When 
 phlegmatic or proof- fpirits are required for chemical or other curious ufes, 
 they ought always to be prepared in this manner (/). 
 
 Spirit of Wine, fet on fire in a fpoon or ladle, burns wholly away, without 
 leaving any fenfible humidity. A little Gunpowder, placed at the bottom, 
 takes fire as foon as the fpirit is burnt off; and this is the common mark of 
 the fpirit being fufficiently redified; for if it contains any confiderable quan- 
 tity of phlegm, this phlegm remaining after the fpirit is conlumed, will pre- 
 vent the Gunpowder from taking fire. The makers of varmfh, who require 
 very ftrong fpirits, prefer Cotton as a nicer tell, this being lefs eafily inflam- 
 mable than Gunpowder-, and a fmaller proportion of aqueous humidity pre- 
 venting its burning. A fpirit that fires Cotton is looked upon as quite pure 
 from phlegm. 
 
 Though redified fpirits give no figns of water upon thefe trials, a further 
 rectified fpirit. examination difeovers that they abound with that element. Burn the ftrongeft 
 fpirits in a deep mortar, or in a veflel kept floating in cold water, and a quan- 
 tity of moiflure will remain unconfumed. I made feveral experiments on this 
 fubjed at Paris, in concert with the younger Geoffroy, who afterwards gave an 
 account of them to the French Academy : From the belt fpirits, fuch as fired 
 both Gunpowder and Cotton, we gained, by burning them in the open air, one 
 third their weight of water -, and under an open glafs receiver, one half. I 
 have fince colleded much larger quantities, by burning the fpirit in an appara- 
 tus which differed lefs of the phlegm toefcape into the air. 
 
 Pure fpirit is in effed, no other than an intimate combination of water with 
 an Oil -, not fuch an Oil as we feparate in the redification, but one that has 
 been highly fubtilized by the procefs of fermentation : An adual Oil is obtain- 
 able from the pureft fpirit, by diffilling it with the vitriolic acid. Thefe fpirits 
 contain alfo a portion of acid, which probably ferves as the band of union be- 
 tween the Oil and the water : On repeatedly abftrading frefh quantities of 
 them from one and the fame parcel of fixed alcaline Salt, the Salt becomes at 
 length neutral, and nearly fimilar to alcalies neutralized by Vinegar. 
 
 Vinous fpirits Vinous fpirits are of very extenfive life in chemiffry and the chemical arts; 
 as menftrua. as for feparating the medicinal parts of vegetable and animal fubfiances, from 
 the inadive matter; extrading their flavours and colours for various ufes ; 
 diffoiving Refin and Oils for varnifhing and lacquering; preferving animal 
 and vegetable 
 
 bodies from corruption. 
 
 acid in its pure date, as we could not afeer- 
 tain the proper quantity ; but Vitriol itfelf, or 
 Alum, may be ufed with fafety, as thefe 
 will part with no more of their acid, in the 
 degree of heat by which vinous fpirits are 
 diitilled, than what the alcali abforbs. 
 
 (/) Proof fpirits from rectified fpirit and wa~ 
 
 Spirit 
 
 ter.] Proof fpirits are faid to be compofed of 
 equal parts of redified fpirit and water. If 
 the two liquors are taken by meafure, this 
 proportion will pretty nearly make a fpirit of 
 the ftrength commonly underftood by proof. 
 The exad proportions, by weight, are, one 
 hundred parts of pure fpirit, and eighty-fix 
 of water. 
 
Artificial Vegetable Productions. 453 
 
 Spirit of Wine diffolves all vegetable Refins and diftilled Oils, the fubtile Vinous 
 Oils of aromatic herbs, flowers, feeds and fruits, as Lavender, Balm, Mint, Spirits. 
 Marjoram, Citron- peel, very readily and plentifully, thofe of woods and roots, ' — — -v~- 
 as Rhodium and Saffafras, more difficultly and fparingly ; thole diftilled from 
 refinous lubftances, as Turpentine, and from mineral bitumens as Amber, ftiil 
 more difficultly. It diftolves empyreumatic Oils as well as the effential-, and by 
 diftillation and repeated cohobation, renders them extremely fubtile. Pure ex- 
 prefied Oils, and animal Fats, it does not unite with at all-, but thefe alfo are 
 rendered folublein it by combining them with fixed alcaline Salts into Sope. It 
 mingles with water, and produces a confiderable heat on being mixed with it. It 
 coagulates Blood, Milk, and whites of Eggs, and molt of the animal juices, ex- 
 cept Urine and Bile. It mingles with all acids, concentrated and diluted, of the 
 mineral or vegetable kingdom : On its mixture with the concentrated mineral acid 
 fpirits, a ftrong ebullition and heat enfue, the acidity is obtunded or deftroyed, 
 and the compound proves a fubtile, volatile, fragrant fluid («). It does not 
 a<ft in the lealt upon pure Sulphur ; but from Sulphur combined with fixed al- 
 caline 
 
 ( u ) Combination of vinous fpirits with mineral 
 acicls.] Spirit of Wine produces the greateft 
 heat and ebullition on mixture with the ni- 
 trous acid ; and the leak with the marine. 
 The conflict is confiderably more violent, 
 and the noxious fumes more copious, when 
 the vinous fpirit is dropt into the acid, than 
 when the acid is dropt into the vinous ; a 
 circumftance to be carefully attended to by 
 the operator in making thefe mixtures, efpe- 
 cially when the quantities are large. When 
 the two fpirits are intimately combined to- 
 gether into a fragrant liquor, in which no 
 acidity can be perceived, the acid is faid to 
 be dulcified. The union is promoted by di- 
 geftion ; but the dulcification is never per- 
 fect without a fubfequent diftillation. As 
 fome Angular phaenomena occur in thefe ope- 
 rations, it will be proper to conftder them 
 more particularly. 
 
 With the vitriolic acid.] Concentrated Oil 
 of Vitriol being dropt by degrees into an 
 equal quantity, or five or fix times its quan- 
 tity, of highly rectified Spirit of Wine, the 
 liquor becomes firftyellow and thenreddifh, 
 and exhales an agreeable, diffufive, pene- 
 trating fmell, which if freely taken in with 
 the breath, affedts the lungs : The tafte of 
 the liquor is confiderably acid. 
 
 On digefting the mixture for fome days, 
 and then committing it to diftillation in a 
 retort with a very gentle warmth, there 
 arifes a fubtile fpirit, more fragrant and pe- 
 5 
 
 netrating in fmell than the undiftilled liquor,, 
 very volatile, inflammable, in tafte not at all 
 acid, but of the aromatic kind. This is the 
 dulcified Spirit of Vitriol. It comes over in 
 thin invifible vapours, which condenfe upon 
 the Tides of the recipient in ftreight Arise. 
 
 This fpirit is fucceeded by one of a diffe- 
 rent kind ; which being caught in a feparate 
 receiver, is found to be fenfibly acid, and of 
 a pungent fuffocating fmell like the fumes 
 of burning Brimftone. Along with it comes 
 over a fmall quantity of Oil ; which fome- 
 times proves colourlefs and fwims on the 
 fulphnreous liquor, and fometimes appears 
 yellowifh or greenifh and finks to the bot- 
 tom, according as the vinous fpirit in the 
 mixture w'as in large or in fmall propor- 
 tion. 
 
 In all the diftillations I have made, this fu'- 
 phureous fpirit arofe in white fumes, which 
 either formed irregular ftriae, or were col- 
 lected into large round drops like Oil : The 
 appearance of thefe fumes conftantly gave 
 notice of the time for changing the receiver. 
 Mr. Hellot fays, that in perfectly clofe vef- 
 fels, thefe vapours are not to be diftinguifh- 
 ed, any more than thofe of the dulcified fpi- 
 rit ; that when the retort was made to fit 
 exactly into the receiver, the neck being 
 ground with Emery for that purpofe, they 
 were not to be feen till the juncture was 
 loofened a little ; and that on loofening, and 
 flopping it tight, they appeared and difap- 
 peared for feveral times fucceffively. 
 
 On 
 
45 4 
 
 Vinous 
 
 Spirits. 
 
 Artificial Vegetable Productions. 
 
 On continuing the diftillation, a black 
 froth begins haftily to arife, and prevents 
 our carrying the procefs further. The mat- 
 ter which remains in the retort, is of a dark 
 blackilh colour, and ftill highly acid. Treat- 
 ed with frefh Spirit of Wine, in the fame 
 manner as before, it yields the fame pro- 
 ductions, till at length, all the acid that re- 
 mains unvolatilized being fatiated with the 
 inflammable oily matter of the fpirit, the 
 compound proves a bituminous fulphureous 
 mafs ; which expofed to the fire in open 
 veffels readily burns, leaving a confiderable 
 quantity of fixed afhes ; in clofe ones, ex- 
 plodes with violence ; and with fixed alca- 
 ]ine Salts forms a compound fimilar in fome 
 refpedts to one compofed of alcalies and 
 Sulphur. 
 
 The author above-mentioned has difco- 
 vered a method of facilitating this procefs, 
 in regard to the preparation of the dulcified 
 fpirit. By the addition of powdered Potter’s- 
 earth, in the proportion of fix ounces to eight 
 ounces of the acid andfixteenof the vinous 
 fpirit, the fulphureous liquor and the Oil 
 that accompanies it are prevented, he fays, 
 from arifing ; and the diftillation may be 
 fafely performed even with a boiling heat, 
 and continued till the matter remains dry. 
 See the Memoirs of the French Academy 
 for the year 1 7 39 — It is probable, that the 
 only ufe of this addition is, to abforb the 
 fuperfluous acid ; for the author obferves 
 that greateft part of the Oil of Vitriol is 
 recoverable from the Clay, by diftilling it 
 with aftronger fire. Perhaps a fuitable di- 
 minution in the quantity of acid employed 
 might anfwer the fame end. Thus much 
 is certain, that when fix parts of the vinous 
 fpirit are’ taken to one of the acid, the 
 quantity both of fulphureous liquor and Oil 
 is confiderably lefs than when the two fpi- 
 rits are taken in equal proportions. 
 
 The Oil is of a ftrong, penetrating, a- 
 greeable fmell, refembling that of the dulci- 
 fied fpirit : It very readily and totally dif- 
 
 folves in rectified Spirit of Wine, and im- 
 pregnates a large quantity of the menftruum 
 with its own odour. To the tafte, it is 
 fenfibly acid, efpecially when a large pro- 
 portion of acid has been employed in the 
 procefs : On keeping for fome time, it be- 
 comes more remarkably fo, acquiring at the 
 fame time a reddifh hue. In this ftate, it 
 difcovers a fulphureous fmell, efFervefces 
 
 with and neutralizes alcaline Salts, and be- 
 ing thus freed from its acid, arifes in diftil- 
 lation more fubtile than before, and vaftly 
 diminifhedin quantity. 
 
 The dulcified lpirit alfo has frequently 
 fome flight acidity, fufficient to alter the 
 fine green tindture, which in its perfedt ftate 
 it extradfs from the leaves of plants. It is 
 purified or redfified from this redundant 
 acid, by mixing it with a weak folution of 
 fixed alcaline Salt, and diftilling it over a 
 fecond time: For every pint of the fpirit 
 may be taken a folution of a dram of Alcali 
 in a pint of water. 
 
 If the fpirit, thus redtified, be mingled 
 again with an equal quantity of a like alca- 
 line folution, the mixture fhaken together, 
 appears milky: On ftanding for a little 
 time, there arifes to the furface an extremely 
 fubtile fluid, called by the chemifts ./Ether, 
 or /Ethereal Spirit of Wine. A confider- 
 able quantity of dulcified fpirit may ftill be 
 feparated from the remaining liquor by di- 
 ftillation ; and this fpirit, mixed with freih 
 alcaline folution, affords more /Ether. 
 
 The /Ether is the lighteft, moft volatile, 
 and moft inflammable of all known liquids. 
 It fvvims on the moft highly redtified Spirit 
 of Wine, being lighter than that fpirit in 
 the proportion nearly of 0,730 to 0,830. 
 Dropt on the warm hand, it almoft inftantly 
 exhales, diftufing a penetrating fragrance, 
 and leaving no moifture behind. On the 
 approach of a candle, it takes fire, and goes 
 oft' in a flafh like lightening. It does not 
 mingle with water, with acid, or with alca- 
 line liquors ; but diflolves fome undtuous 
 and refinous bodies. Among metallic fub- 
 ftances, it difcovers a remarkable attradtion 
 to Gold, but feems to have no effedt on any 
 of the others : Mixed with a folution of 
 Gold made in acids, it imbibes the Gold 
 from the acid, carries it to the furface, and 
 keeps it there diffolved into a yellow liquor ; 
 hence its ufe for difcovering Gold in liquids. 
 See page 39. 
 
 The only perfon we know of, who has 
 given any plaufible theory of the produdtion 
 of this fubtile fluid, is Mr. Macquer---Spirit 
 of Wine confifts chiefly of an Oil, exqui- 
 fitely attenuated by fermentation, and inti- 
 mately combined with water. According to 
 Mr. Macquer, the /Ether is no other than 
 this fubtilized Oil, extricated by the vitriolic 
 acid ; which acid, having a ftrong affinity 
 
 or 
 
Artificial Vegetable ProduSUons . 
 
 or attraction to water, abforbs the watery 
 element of the fpirit, and thus fets the oily 
 one at liberty. 
 
 In the Svenjka vetenjkaps academiens handlin- 
 gor , dr. 1 740, there is a remarkable experi- 
 ment on the dulcified vitriolic fpirit (or per- 
 haps the ./Ether, for the author expreffes 
 himfelfa little ambiguoufly) by J. G. Wal- 
 lerius. Some Salt of Tartar being mixed 
 wich the fpirit, the full bottle ftopt with a 
 cork, tied over with bladder, and laid on its 
 fide ; on Handing for four months, greateft 
 part of the fpirit v/as found to have efcaped, 
 and the Salt was fhot into hexangular prif- 
 matic cryftals like Nitre. It tailed ftrongly 
 of the fpirit, but had no other particular 
 tafte : Laid on a burning coal, it crackled 
 and exploded with a bright flafh, and flew 
 with violence into the air. He afterwards 
 found, that by adding to the fpirit a drop or 
 two of any acid, the Salt cryftallizes the 
 fooner ; that in this cafe it proves of a fou- 
 rifh tafte, but in other refpefts is the fame 
 as that made without the acid. This Salt- 
 peter, fays the author, promifes, from the 
 violence of its explofton, to make the 
 ftrongeft Gunpowder in the world, but a 
 very dear one : Though the experiment 
 
 fhould not be applicable to any ufe in this 
 way, it will probably contribute to illuftrate 
 the generation of Nitre, as it palpably fliews 
 Nitre (that is the acid or charadteriftic part 
 of Nitre) produced from the vitriolic acid 
 and phlogifton. 
 
 With the nitrous acid.] Strong Spirit of 
 Nitre being dropt by little and little into 
 three or four times its quantity of redtified 
 Spirit of Wine ; and the mixture, after di- 
 geftion for fome days, diftilled by the heat 
 of a water-bath, there arifes a fragrant fpi- 
 rit, in fome degree refembling the dulcified 
 Spirit of Vitriol ; but which, when rectified 
 in the fame manner, does not, fo far as I 
 have obferved, afford any Oil or iEther. 
 The fpirit is to the tafte gratefully pungent, 
 not at ail aciTlike the one ingredient, nor 
 hot like the other : Mixed with clean Malt 
 or Melaffes fpirits, it communicates a fla- 
 vour like that of French Brandy. It is 
 confiderably lefs inflammable than Spirit of 
 Wine, and leaves on burning an acidulous 
 phlegm. 
 
 It is obfervable, that the vitriolic acid, in 
 the foregoing procefs, difcovers itfelf in moll 
 
 of the produdts by its ufual charadters, Vi 
 plainly in the fulphureous diftilled liquor and g pi 
 in the Oil that diftils along with it, and ftill t __ 
 more plentifully in the refiduum ; whilft 
 the whole of the nitrous acid, in theprefent 
 procefs, feems to be deftroyed or to change 
 its nature. To deflagrate with inflammable 
 fubftances in burning, is the ftrongeft cha- 
 racter of the nitrous acid ; but neither the 
 dulcified fpirit, nor the acidulous liquor re- 
 maining after it has been burnt, nor the 
 matter left in the retort after the diftillation, 
 have been obferved to produce any defla- 
 gration. 
 
 Mr. Pott, in a differtation on this fubjedt, 
 has given fome curious experiments on the 
 oleaginous refiduum of the diftillation— Di- 
 ftilled by a ftronger fire, it gave over a yel- 
 low acid flightly empyreumatic fpirit; which 
 being laturated with fixed alcali, the liquor 
 evaporated, and the dry neutral Salt laid on 
 burning coals, no deflagration enfued. Af- 
 ter this fpirit, arofe a red empyreumatic 
 Oil ; and in the bottom of the veffel re- 
 mained a fhining black mafs like Soot, 
 which burnt in a crucible left a white fixed 
 earth, convertible by a vehement fire into 
 Glafs---Ancther parcel of the above refi- 
 duum was evaporated to the confiftence of 
 Pitch: In this ftate, it gave a yellow tinc- 
 ture to Spirit of Wine, flamed vividly and 
 quietly on burning coals, and at laft fwelled 
 up like Bitumens — Another portion was 
 laturated with alcaline Ley (with winch it 
 immediately effervefced) and then evapo- 
 rated as the former : It gave as before a 
 
 yellow tindture to rectified Spirit of Wine, 
 and a much deeper yellow to the dulcified 
 Spirit of Nitre; and in the fire difcovered 
 no footftep of detonation — Mr. Macquer, 
 who mentions fome of thefe experiments 
 without giving them their full force, lufpedts 
 that the acid obferved in them was not the 
 nitrous changed in its quality, but the acid 
 of the Spirit of Wine extricated by the ni- 
 trous. But what is become then of the 
 nitrou&scid, of which fo large a proportion 
 was made ufe of ? 
 
 Though the nitrous acid does not fepa- 
 rate any sethereal Oil from Spirit of Wine, 
 by diftillation in a gentle heat, as the vitrio- 
 lic does ; it feparates one by fimple mix- 
 ture, and digeftion without heat, which the 
 vitriolic does not. Equal parts by meafure 
 of Spirit of Nitre and Spirit of Wine being 
 
 mixed : . 
 
4 56 Artificial V ° get able Productions. 
 
 Vinous caline Salts, it receives a deep yellow tin&ure, and a notable tafte and finell. 
 
 Spirits. It has been faid to dififolve no folid Salts ; but on trial it is found to diflolve 
 -v- — J perfectly the Sal diureticus, nitrous Sal ammoniac, the Salt called fixed Sal am- 
 moniac, the cryftals of Silver made with the nitrous acid, and combinations of 
 Iron, and fome other metallic bodies with the marine; and more difficultly 
 Sugar, Saccharum faturni, and Salt of Amber: It takes up a little alfo, about 
 one fixth, of green Vitriol, and of Borax. Added to watery folutions of Salts, 
 it in fome cafes occafions an inftantaneous precipitation of the Salt, by render- 
 ing the water incapable of keeping it difiblved : With fome folutions it pro- 
 duces a coagulum : From fome it precipitates the earthy or metallic bafis of 
 
 the Salt, the acid being abforbed by the fpirit, It revives Gold from its folu- 
 tions in form of fine Gold-leaf, and precipitates Mercury in its running form : 
 It precipitates alfo Tin and Lead. It does not ad, or at lead: not confiderably, 
 upon pure alcaline Salts, either fixed or volatile, nor mingle with folutions of 
 them made in water: It abforbs the water from folutions of volatile alcaiies, 
 and thus precipitates the Salt; but on folutions of fixed alcaiies it has no 
 effed, the fpirit fwimming diftind upon the furface of the alcaline liquor, and 
 quickly feparating from it, though they be ftrongly lliaken together, as Oil 
 does from water. 
 
 tartar. 
 
 Tartar. T II L grofs Salt, or Tartar, contained in Wines, does not difiolve at all in 
 
 v_ j fpirit, and very fparingly in watery liquors : By age. Wines become more 
 
 Its produdh- anc j m0 re fpirituous, and the Tartar proportionably feparates and incruflates on 
 the fides and bottom of thecafk. It proves of a whitifh, yellowiih or reddifh 
 colour according to that of the Wine; and more or lefs foul according as the 
 Wine abounded more or lefs with grofs unduous matter. The white is purer 
 than the red ; and that which feparates after the Wine has been long kept, than 
 fuch as is thrown off immediately after the fermentation. 
 
 This 
 
 mixed together, the bottle clofely ftopt, and 
 fet in a cool place; the aethereal Oil, in fe- 
 ven or eight days, arifes to the furface, a- 
 mounting to upwards of one fourth the 
 quantity of the mixture. This Oil contains 
 a part of the nitrous acid unchanged : From 
 which it is purified by diftillation from alca- 
 line liquors, and is then called rectified ni- 
 trous aether. This experiment was firft 
 difeovered by Mr. Navier, and communi- 
 cated in the Memoirs of the French Aca- 
 demy for the year 1742. It adocs not re- 
 quire the two fpirits to be very ftrong, and 
 is performed with the greateft fafety to the 
 operator when they are but moderately fo : 
 When both of them are highly concen- 
 trated, there fometimes happens, during the 
 digeftion, a violent explofion. 
 
 With the marine acid J The marine acid 
 unites with vinous fpirits very difficultly and 
 imperfeCtly: When combined with them 
 by long digeftion and diftillation, it mani- 
 fefts its own fpecific characters, and feems 
 to be only diluted by the inflammable li- 
 quor. The fpirit, diftilled in the heat of a 
 water-bath from one part of fmoking Spirit 
 of Salt and three or four of highly rectified 
 Spirit of Wine, after twenty 1 days digeftion, 
 effervefees with fixed alcaiies, forms with 
 them a regenerated Sea-falt, and precipi- 
 tates Silver from its folution in Aqua fortis 
 into Luna cornea. The matter left after 
 the diftillation yields, on being urged with 
 a greater heat, a weak marine fpirit, flightly 
 empyreumatic, a pitchy or coaly matter re- 
 maining, which by calcination turns to 
 white allies. 
 
Artificial V egetable ProduSlions. q_ c - 
 
 This Salt is the direct produce of fermentation, and is never to be obtained Tartar. 
 from liquors which have not undergone that procels. The rich fweet Wines —v — — j 
 
 afford lead ; not, as Boerhaave l'uppofes, from the oiiy matter preventing its 
 reparation, but from their really containing lead, as having been lead perfectly 
 fermented. The Rhenifh, Franconia and Mofelle Wines yield the mod of any. 
 
 Tartar is always the fame Salt, whatever Wine it be produced from; the Purifications, 
 only difference that arifes from the Wine being in the quantity of foul matter 
 depofited along with it. It is purified by boiling it in water till the faline part 
 is diffolved, and clarifying the drained folution with whites of Eggs : The li- 
 quor being then removed into a cool place, the Salt foon begins to concrete 
 into very fmall white crydals. 
 
 Tartar is refined in large quantity at Venice, Montpelier, Tripoli, and in 
 fome parts of Germany : The crydals we are fupplied with from thole works 
 are fomewhat whiter, and much larger, than any I have been able to prepare ; 
 and at the fame time of a cheapnefs fcarce confident with the troubiefome oro- 
 cefs of diffolving and clarifying the Tartar by itfelf. Some of the chemifts of 
 the French Academy have taken great pains to difcover the method of ma- 
 nagement in the Tartar refinery at Montpelier ; and report, that the fecret 
 conlids in employing a chalky earth, which promotes the folution of the Tar- 
 tar. I have never been able to fucceed with chalky or with other earths, nor 
 with any of the additions I have made trial of. Chalk and abforbent earths in 
 general do indeed promote the folution of the Tartar, but they unite with it 
 into a new compound of a quite different nature ; whereas the common Cry- 
 ftals were found on all trials the fame with Tartar purified by itfelf, 
 
 Tartar is a manifedly acid Salt : It does not, however, change the colour ofits general 
 Syrup of Violets to a red, the oily matter, with which it abounds, covering its properties, 
 acidity. Diffolved in water, it effervelces with fixed alcalineSalts, and forms with 
 them a neutral one, much eafier of folution than the Tartar alone. It likewife 
 effervefces with and dilfolves abforbent earths, and with thefe alio forms a neu- 
 tral foluble compound, from which the tartareous acid may be expelled by the 
 more powerful ones of the mineral kingdom. It diffolves the metallic fub- 
 fiances that other vegetable acids do, as Iron, Copper, Lead, CtV. (*). 
 
 Tartar, 
 
 (x) Tartar .] The acid of Tartar has been 
 fuppofed by fome to be fimilar to that of 
 Vinegar, but is found upon experiment to 
 be notably different. It does not, like the 
 acetous acid, render fixed alcalies foluble in 
 Spirit of Wine, nor form a faccharine con- 
 crete with Lead. When combined with 
 alcaline Salts, or with abforbent earths, into 
 a neutral Salt ; Vinegar, as well as the mi- 
 neral acids, added to a folution of this Salt, 
 precipitates the Tartar in its original form, 
 and unites with the alcali or earth in itsftead. 
 
 It is obfervable, that all the fubftances, 
 which unite with Tartar, form with it com- 
 pounds eafier of folution than the Tartar 
 
 N 
 
 by itfelf; thofe of the metallic kind not 
 excepted. Thus if Tartar andiron-filings 
 be boiled together in water, the liquor foon 
 acquires a dark colour and a ferrugineous 
 tafte : On cooling, fuch part of the Tartar 
 as is but (lightly impregnated with the Iron, 
 falls to the bottom in a cryftallir.e form, 
 the part which is fully faturated remaining 
 diffolved in the cold : If the fluid be now 
 evaporated, it leaves a faline mafs, fo eafy 
 of folution, that it runs into a liquor on be- 
 ing expofed to the air. The addition of al- 
 caline Salts to this folution does not feem to 
 precipitate the Iron from the tartareous acid \ 
 but on adding any other acid, the Tartar is 
 n n preci- 
 
458 Artificial Vegetable ProduSUons . 
 
 Tartar, Tartar, expofed to the fire in clofe veffels, gives over a fetid acidulous fpi- 
 — v- — rit, and an ernpyreumaticOil: The remaining coal, elixated with water, yields 
 Refolucion by a j ar g e proportion of fixed alcaline Salt, whiift no fuch Salt is producible from 
 2lt * other vegetable ma ters without burning them to white or whitifh allies in the 
 
 open air. From a pound of Tartar were extracted about four ounces of fpirit 
 and phlegm, and one of Oil: The re fid uu 111 weighed ten ounces and a half, 
 and yielded four ounces ol alcaline Salt. This is the alcali which has been 
 chiefly made ufe of in chemical experiments, by the name of Salt of Tartar : 
 It is not different in quality from the alcalies obtained from other vegetables, 
 though it feems to have been looked upon by fome as participating of the na- 
 ture of the Tartar itfelf; whence compound Salts in which it is an ingredient 
 are called by the name of Tartar, as vitriolated Tartar, tartarized Tartar, &c. 
 
 It is remarkable, that when four parts of powdered Tartar and three of pow- 
 dered Quick- lime are mixed together, and thoroughly calcined in a crucibie, 
 the product has neither fmell nor talle, and being thrown into water, lies, im- 
 aged on, like a done : On digefting the mafs in water for a little time, it grows 
 hot, and yields an exceeding throng cauftic alcali. 
 
 Its ufes. Tartar is ufed in medicine as a mild cooling purgative. Its principal con- 
 
 fumption is in the chemical arts, particularly dying, glafs-making, metal- 
 lurgy, in making Vinegar, Nitre, &c. 
 
 VINEGAR. 
 
 Vinegar 
 V- J 
 
 Its produc- 
 tion. 
 
 \T I NEG AR is the produce of the fecond ftage of fermentation. If Wines 
 or vinous liquors be expofed to a gentle continued warmth, the acetous 
 fermentation fpontaneoufly lucceeds : A grofs tartareous and undtuous matter 
 
 falls 
 
 precipitated, the Iron which made it foluble, 
 being abforbed from it by the acid fuper- 
 added. Nearly the fame phenomena are 
 oblerved on treating Tartar with Copper, 
 Lead, Zinc, andRegulus of Antimony, ex- 
 cept that the combinations with thefe me- 
 tals are lefs difpofed to deliquiate. 
 
 Tartar faturates about one third its 
 weight of fixed alcaline Salt, but more than 
 equal its weight of abforbent earth. If the 
 Tartar be diflolved in boiling water, and 
 the proper quantity of the alcali or earth be 
 gradually thrown into the boiling liquor; 
 the whole of the Tartar will be faturated at 
 ouce, fo as to yield on cryftallization a Salt 
 perfedfly neutralized and eafily foluble. Me- 
 tallic bodies on the other hand, though long 
 boiled with a folution of Tartar, faturate 
 only a part of it, and commonly but a fmail 
 one : The Cryftals which feparate firft from 
 the liquor are little other than Cryftals of 
 Tartar; thofe which fucceed are more and 
 more impregnated with the metal ; the part 
 which is fully faturated remaining diffolved 
 
 to the lad. This property of Tartar ought 
 to be well attended to, in the proceffes of 
 impregnating it with metallic bodies, as 
 particularly with the reguline part of Anti- 
 mony, for medicinal ufe. See page 137. 
 
 Borax, a Salt very difficult of folurion 
 by itfelf, has a remarkable effedi on Tartar. 
 Two ounces of Borax and four of Cryftals 
 of Tartar diflblve, (without the effervefcence 
 which Tartar always excites with alcaline 
 Salts and earths) in twelve ounces of water; 
 which is no more than about one fixth part 
 of the quantity that would be neceflary to 
 diflhlve them feparately. On evaporating 
 the liquor, the Salts concrete into an aci- 
 dulous, vifeous, tenacious mafs, like Glue, 
 which refufes to cryftallize, and which if 
 exficcated by heat, deliquiates again in the 
 air. 
 
 In all thefe combinations of Tartar, its 
 acid continues united with its grofs Oil and 
 earth : Nor do we know of any method of 
 extricating or feparating it from them, or of 
 transferring it into any other body. 
 
Artificial Vegetable ProduElions . 
 
 459 
 
 falls to the bottom ; the inflammable fpirit is refolved or deftroyed, and per- Vinegar. 
 haps a part of it efcapes ; rhe liquor gradually lofes its confidence, its fweetnefs 
 and its vinous flavour, and becomes a thin acid Vinegar. The acetous fer- 
 mentation naturally follows the vinous, but is not necefiarily preceded by it ; 
 
 Vinegar being producible without any intermediate ftate of vinofity. 
 
 When Vinegar has run a little beyond the acetous ftate, and begun to enter Recovery 
 on the putrefactive, it is ftill in the power of art to recover it. The putrefac- from 
 tion may be ftopt by quenching a red-hot Iron in the liquor; and the aad, r 
 which has been loft or deftroyed, may in fome meafure be reftored, by the ad- 
 dition ot a little Spirit of Wine, Rye-bread, Muftard-feed, &c. The putre- 
 faction of Vinegar is prevented in the fame manner as the fretting or acetifica- 
 tion of Wine ; by racking it off from the feculencies, and keeping it in a clofe 
 ftopt vefiel in a cool place. Such as has once fullered a confiderable heat, can- 
 not long be preferved from corruption. 
 
 Vinegar is compofed of phlegm or water, the proper acetous acid, a groflerlts principles, 
 acid approaching to that of Tartar, and an unCtuous or oily matter. In diftil- 
 lation with a gentle fire, the phlegm and the acetous acid arife, with fome of 
 the finer parts of the Oil, the tartareous acid, and the groffer Oil, remaining 
 at the bottom. The Vinegars made from Malt-liquors contain more unCtuous 
 matter than thofe from Wine, and give out their acid more difficultly. Vine- 
 gar feems to contain aifo a fmall portion of the vinous fpirit, that has not been 
 changed or fubdued by the fermentation. 
 
 The diftillation of Vinegar in retorts, recommended by fome, is very trouble -Diftillation of 
 fome and incommodious. The belt apparatus is a glafs body ora pewter ftill, Vinegar, 
 fitted with a glafs or ftone- ware head. The compilers of the Brandenburg 
 Difpenfatory have judicioully ordered the diftillation to be performed in a water- 
 bath, but fubjoin a very needlefs caution of guarding againft an empyreuma: 
 
 The very advantage of the water-bath is, that we may lately draw over all that 
 will arife, without danger, and even without a pofiibility, of giving any em- 
 pyreumatic tafte or fmell to the fpirit. The phlegmatic part, which cl i ft i 1 s at 
 firft, may be thrown away; and the weaker acid, which comes over next, kept 
 apart from the ftronger acid that follows. 
 
 The matter remaining after the diftillation, urged with a ftronger fire in aFurther exa- 
 retort, yields an empyreumatic Oil, and an extremely acid tartareous fpirit, j?' nat i° n by 
 tainted with the burnt flavour of the Oil, from which it may be in good mea- 4 
 fure treed by repeated diftillation. From the coal left in the bottom of the re- 
 tort, may be obtained, by burning it in the open air, a fixed alcaline Salt more 
 lubtile and penetrating than the common alcalies. If Vinegar be drawn over 
 from Quick-lime, and the remaining mafs diftilled in a retort, there arifes a 
 ftrong volatile alcaline fpirit, which ads notably on fome metallic bodies. Thus 
 is a part at leaft of this acid liquor convertible by Ample procefles into alcalies 
 both fixed and volatile. 
 
 The ancients mixed Vinegar with different kinds of fubftances for medicinal Preparations, 
 ufe, and diftinguifhed the mixtures by different names expreffive of the ingre- 
 dients : Their Oxycraton or Pojca was compofed of Vinegar and Water ; Oxe- 
 leum, of Vinegar and Oil ; Oxalme , of Vinegar and Salt-water ; Tkymoxalme , of 
 Vinegar and Salt-water impregnated with Thy me ; Qxylepus, of Vinegar and- 
 
 N n n 2 , the 
 
460 
 
 Vjneg ar. 
 
 ■■■ ■ — * 
 
 Medicated 
 
 Vinegars. 
 
 Vinegar as 
 jnenffruu-m. 
 
 Artificial Vegetable Produ&ions. 
 
 the Cortex f alarum \ Oxyrrhodinum , of Vinegar and Oil of Rofes or Rofe- water ; 
 Oxyfaecharum , of Vinegar and Sugar; and Oxyglyci, or Oxymel, of Vinegar and 
 Honey. Oxyfacchara and Oxymels are (till retained in practice : They are pre- 
 
 pared by diffolving Sugar or Honey in a proper quantity of Vinegar, with or 
 without the addition of other ingredients, and boiling down the mixture to the 
 confiftence of afyrup : They are, in eflfedt, no other than fyrups, made with 
 Vinegar inftead of water. 
 
 Medicated Vinegars are infufions of different vegetable fubftances made in 
 this acid liquor. If the Vinegar is digefted with the herbs, flowers, feiV. in a 
 glafs body or other convenient veflfel, with a gentle heat, it becomes impreg- 
 nated with their virtues much more fpeedily and effectually than by the expo- 
 fure to the fun generally directed. Vinegar may likewife be medicated or fla- 
 voured by adding the fubjeCt to the Wine or to the Muft at firft : There are 
 many vegetables whofe fmell and tafte refill both the vinous and acetous fer- 
 mentation, and remain ftrong in the Vinegar. 
 
 1 Vinegar diffolves all the earths that the mineral acids diffolve, and feveral of 
 the metallic bodies. Lead is corroded by its vapour into Ceruffe or white 
 Lead : Ceruffe, or the calces of Lead made by fire, diffolve in Vinegar, and 
 on infpiffation flioot intoCryftals called Saccharum faturni. From Iron and 
 Steel are prepared, by this acid, Chalybeate tinCtures and extracts. Copper 
 is corroded by it (or by the acefcent preffings of Grapes) into Verdegris. See 
 the leveral metals in the firft part of this work {y). Saturated with volatile 
 alcalies, it forms a neutral faiine liquor, which in diftiilation totally arifes in a 
 
 fluid 
 
 ( y) Vinegar as a menflruum for metallic bo- 
 dies. i] This acid differs remarkably in its 
 action on different metallic bodies, accord- 
 ing as they are in their perfeCt metallic 
 ftate, or changed by fire or by other men- 
 ftrua, into the ftate of a calx or crocus. 
 
 It diffolves Zinc very eafily, and Bifmuth 
 more difficultly, in both ftates. It diffolves 
 Iron-filings very readily, but fcarce has any 
 aCtion on the caices of Iron. Filings of 
 Lead on the other hand are very difficultly 
 acted on, but the calces diffolve more eafily : 
 Vinegar boiled even with the glafs of Lead, 
 or in the common glazed earthen-veffels, 
 in whofe glazing this metal is a principal 
 Ingredient, extracts a notable quantity, fo 
 as to become ftxongjy impregnated with the 
 pernicious qualities of the Lead, and to 
 yield on evaporation a true Saccharum faturni . 
 The antimonial Regulus aJfo, both in the 
 form of Glafe and in its metallic ftate, gives 
 a ftrong impregnation to V inegar, whilft its 
 calces, made by deflagration with Nitre, 
 feem to be unaffected by it. 
 
 The habitude of Tin to the acetous acid 
 has been difputed. Our author finds (page 
 
 88.) that this metal does not diffolve in it ; 
 and on the other hand Mr. Marggraf af- 
 firms (in the Berlin Memoirs for the year 
 1747) that it diffolves with eafe. On trial 
 I obferved, that plates of pure Tin, put 
 into common Vinegar, begun in a few 
 hours to be corroded, without the applica- 
 tion of heat: By degrees a portion of the 
 metal was taken up by the acid, but did not 
 feem to be perfeftly diffolved, the liquor 
 appearing quite opake and turbid, and de- 
 pofiting great part of the corroded Tin to the 
 bottom in form of a whitifh powder. A part 
 of the Tin, if it is not truly diffolved, is ex- 
 quifitely divided in the liquor ; for after 
 ftanding for many days, and after paffing 
 through a filter, fo much remained fufpend- 
 ed, as to give a whitilhnefs and opacity to 
 the fluid. Acid juices of fruits, fubftituted 
 to Vinegar, exhibited the fame phenomena. 
 Thefe experiments are not fully conclufive 
 for the real folubility of Tin in thefe acids, 
 with regard to the purpofes for which the 
 chemifts have wanted fuch a folution ; but 
 they prove what is more important, that 
 Tin or tinned veffels, however pure the 
 
 Tin 
 
Artificial Vegetable Productions . 461 
 
 fluid form, without yielding any concrete Salt, as the combinations of the fame Vinegar. 
 alcalies with the mineral acids always do. Combined with fixed alcaiies, it forms — v — * 
 
 a fubtile neutral Salt, foiuble both in water and in Spirit of Wine, commonly 
 called Terra foliata or Arcanum tar tar i : The fame alcalies, combined with other 
 
 acids into a neutral Salt, are not adted upon in the leaft by vinous fpirits 
 
 For this and other like purpofes, diftilled Vinegar is made choice of, not only 
 as being ftronger, but purer from Oil and grofs matter, than Vinegar undi- 
 ftslied. 
 
 To prepare th & Terra foliata tartari in perfection, requires fome nicety. Neutral Salt 
 The alcaline Salt is diffolved in Vinegar, the mixture fet over the fire in a from Vinegar 
 glafa veffel, and more and more Vinegar gradually added during the evapora- and alcali * 
 tion, till a frefh addition occafions no further efifervefcence, and the vapour 
 difcovers an acid fmell. The matter is ftirred during the infpiflation till it be- 
 gins to grow dry when the fire being railed a little, it affumes the foliated ap- 
 pearance from which it receives its name. The colour of the Salt is brown or 
 biackifh : If required white, itmuft be further purified, by folution in Spirit of 
 Wine, or by gently and warily calcining it, then diffolving it in water, and 
 filtering and infpiflating the folution : If the Salt does not yet prove fufficiently 
 white, the calcination and folution in water are to be repeated. During this 
 depuration, it isneceflary to examine whether the Salt continues perfectly neu- 
 tral : If it changes Syrup of Violets green, or a folution of green Vitriol tur- 
 bid, we may be lure that the alcali prevails-, in which cafe, fome more diftil- 
 led Vinegar muft be added. There is no danger of exceeding in the quantity 
 of acid : For though an over-proportion of this has been ufed, whatever there 
 is more than fufficientto neutralize the alcali will be difTipated in the calcination. Concentrated, 
 
 In the Terra foliata , Saccbarum faturni and Verdegris, the pure acetous acid 
 is retained, without much phlegm. Ondiftilling thefe concretes in a retort, a 
 ftronger and more concentrated acid lpirit arifes, than can be obtained by di- 
 ftilling Vinegar by itfelf : This is called Acetum concentration and radicatum. 
 
 Vinegar may be concentrated alfo to a great degree by congelation, the aque- 
 ous part freezing, whilft the acid remains fluid (2), The highly concentrated Dulcified, 
 
 “ ’ fpirit 
 
 Tin be, will give a metalline impregnation 
 to light vegetable acids fuffered to hand in 
 them for a few hours. 
 
 Gold, Platina, Silver, and Quickfilver • 
 are not affedted by Vinegar in their metallic 
 date ; and thefe are the only metallic bo- 
 dies that perfectly refill it. Gold and Pla- 
 tina have not been obferved in any Hate to 
 be affedled by it : Silver precipitated from 
 the nitrous acid and thoroughly edulcorated 
 with water, and Mercury treated in the 
 fame manner or changed by fire into a red 
 powder, ilowly and fparingly diffolve in it. 
 
 Of the affinities of this acid to different 
 metals, or its forfaking one to unite with 
 another, few experiments have been made. 
 
 I have obferved only, that it depofites Lead 
 
 and Copper upon adding Iron. When 
 Copper is diffolved in Vinegar, though in fo 
 fmall a proportion as fcarce fenfibly to dif- 
 cover itfelf by the reputedly moll rigid of all 
 trials, ftriking a blue colour with volatile 
 alcalies ; a polilhed Iron laid in the liquor 
 contrails a cupreous pellicle, in the fame 
 manner as from a folution of Vitriol of 
 Copper (See page 177.) I havefeen vege- 
 table acids, at table, give the firfl notice of 
 their having received a pernicious impreg- 
 nation from Copper veffels, by leaving a 
 copper-coloured ffain upon the knife. 
 
 (%) Concentration of Vinegar. ] The concen- 
 tration of Vinegar by freezing fucceeds bet- 
 ter than that of Wines or vinous liquors. 
 
 We 
 
4.62 Artificial Vegetable Produ&ions. 
 
 Vinegar, fpirit may be dulcified, like the mineral acids, by digeftion and diftillation with 
 — v — equal or twice its quantity of rectified Spirit of Wine. 
 
 Method of The degree of ftrength or acidity of Vinegar may be determined, as that of 
 eilimating its other acids, by neutralizing it with fixed alcaline Salt, and exficcating the 
 ilrength. compound : As the alcali retains only the acid part, the increafe which it has 
 now gained in its weight will give the quantity of acid contained in the Vine- 
 gar. In the following experiments, eight drams, or 480 grains, of each of the 
 Vinegars were employed. 
 
 Table of the Spirit of Pale-beer Vinegar 
 Ilrength of Spirit of Brown-beer V inegar 
 different ine ~ Spirit ot Wine Vinegar - 
 Spirit of Verdegris 
 Concentrated Vinegar - 
 
 CLASS II. 
 
 Products from Vegetables by Fire. 
 
 Saturated of 
 fixed alcali. 
 
 Weight of the 
 neutral Salt. 
 
 Grains. 
 
 Grains. 
 
 1 6 
 
 24 
 
 1 6 
 
 24 
 
 26 
 
 38 
 
 7 2 
 
 120 
 
 270 
 
 437 
 
 Hence the 
 Acid. 
 
 quantity of 
 Phlegm. 
 
 Grains. 
 
 Grains. 
 
 8 
 
 472 
 
 8 
 
 472 
 
 12 
 
 468 
 
 48 
 
 43 2 
 
 1 67 
 
 3 i 3 
 
 T H E effedl of fire upon vegetable fubftances differs greatly, according 
 as the air is excluded or admitted. On diftillation in ciofe veflels, 
 all vegetables give over an Oil, not fuch as it exifted in the original fubjedt, 
 but highly fetid and empyreumatic. Previous to the Oil ariles a portion of 
 phlegm, and from molt vegetables an acidulous, from fome a volatile alcaline 
 
 fpirit. 
 
 We have formerly feen that thofe liquors, 
 whilft their watery part freezes, fuffer a 
 notable alteration in their other principles : 
 The acid of Vinegar is not hurt by the 
 freezing of its phlegm. 
 
 By the operations above propofed, the 
 acetous acid may be concentrated to a de-‘ 
 gree of ftrength, in regard to acidity, greater 
 than even the mineral acid fpirit ofSea-falt 
 can eafily be brought to. It ftill however 
 retains its fpecific properties, and continues 
 as different from any of the mineral acids, 
 as they from one another. Its peculiar 
 tafte and odour, its refufing to cryftallize 
 with volatile alcalies, its forming with fixed 
 ones a neutral Salt which deliquiates in the 
 air and diffolves in Spirit of Wine, its part- 
 ing from the fixed alcali in a moderate fire 
 without any addition, and in fome degree 
 volatilizing the alcali, its being expelled 
 from alcalies, earths and metals by all the 
 
 mineral acids, its effeefts on fome of the me- 
 tallic bodies, are flunking characters of the 
 acetous acid in all its ftates of ftrength. 
 
 Some have been accuftomed to increafe 
 the acidity of weak Vinegar, by the addi- 
 tion of a certain proportion of the acid of 
 Vitriol. The acid of Vitriol is fo different, in 
 its effects upon many bodies, from that of 
 Vinegar, that a moft minute proportion of 
 it is very readily difeovered. Drop into the 
 liquor a little folution of Chalk made in 
 Aqua fortis or Spirit of Salt : If the Vine- 
 gar was pure, no change will enfue : If it 
 contained any vitriolic acid, the mixture 
 will become milky in proportion to the 
 quantity of that acid ; the vitriolic acid unit- 
 ing with the diffolved Chalk into a com- 
 pound no longer diffoluble, and which on 
 Handing lubfides in form of a felenitic 
 powder. 
 
 1 
 
Artificial Vegetable Produ&ions. 463 
 
 fpirit, tainted with the burnt tafte and fmell of the Oil. In the bottom of the By Fire. 
 diftilling veffel remains a black coal, which, fo long as the air is excluded, 
 buffers no further alteration or diminution in the molt intenfe fire, but on ad- 
 mitting the air burns into white afhcs with a notable decreafe of its weight (a). 
 
 Vegetables burnt at firft in the open air, emit a copious fmoke, which is 
 maniteftly impregnated with an acid, and of which a confiderable part may be 
 colledled and condenfed into a black Soot. The afhes which remain give out 
 to water a portion of fixed alcaline Salt ; thole vegetables excepted which yield 
 any confiderable quantity of volatile alcali in the diftillation, for the afhes of 
 thefe fcarcely afford any fixed Salt. 
 
 Intothefe principle s all vegetables and their parts, and all the fubftances ex- 
 tradited from vegetables, are reidluble ; but with fome differences in regard to - 
 the quantities. Thus Gums and Mucilages yield very little Oil, but Refins 
 abundance: From Gums, Mucilages, Refins and Oils we obtain very little 
 alcaline Salt j but from the acid efiential Salts, as that of Sorrel, a large pro- 
 portion. 
 
 EMPY- 
 
 (0 Coal, not alterable without air.] Upon 
 this principle, the method of making Char- 
 coal depends. A quantity of wood, cut in 
 pieces, is piled in a large heap, which is fet 
 on fire, and lightly covered with Turf, to 
 prevent its burning too violently. When 
 the finokeis diffipated,and the wood reduced 
 mto a clear red-hot coal, the whole is im- 
 mediately covered clofely over with earth, 
 which, by excluding the external air, pre- 
 vents the coals from being any farther con- 
 iumed. When the procefs is (kilfully ma- 
 naged, the coals exaftly retain the figure of 
 the pieces of wood : Some have been fo 
 dextrous as to char an arrow, without 
 
 altering the form even of the feather 
 
 Pitcoal alfo is for fome purpofes advantage- 
 oufly charred ; as for the drying of Malt, 
 and the fmelting of metals ; the fuliginous 
 and fulphureous parts, which would give a 
 taint to the one and brittlenefs to the other, 
 being thus diiiipated, whilft the more pure 
 and fixed ignefcible matter is left. 
 
 There are confiderable differences in the 
 coals of different vegetables, in regard to 
 their habitude to fire. The very light coals 
 of Linen, Cotton, fome Fungi, &c. readily 
 catch fire from a fparlc, and foon burn out : 
 The more denfe ones of woods and roots, 
 are fet on fire more difficultly, and burn more 
 flowly. The coals of the black berry-bearing 
 Alder, of the Hazel, the Willow, and the 
 Lime-tree, are faid to anfwer belt for the 
 making of Gunpowder and other pyrotech- 
 
 nical compofitions ; perhaps from their be- 
 ing eafily inflammable. For the reduction 
 of metallic calces, thofe of the heavier 
 woods, as the Oak and the Beech, are pre- 
 ferable; thefe feeming to contain a larger 
 proportion of the phlogiftic principle, and 
 that perhaps in a more fixed ftate. Confi- 
 dered as common fuel, thofe of the heavy 
 woods give the greateft heat, and require the 
 mod plentiful fupply of air to keep them 
 burning : Thofe of the light woods preferve 
 a glowing heat, without much draught of 
 air, till the coals themfelves are confirmed : 
 The bark commonly crackles and Hies about 
 in burning, which the coal of the wood it- 
 felf very feldom does. 
 
 Coals are indifpofed to putrefy : Hence 
 the ends of wooden pofls, to be fixed in the 
 earth, are charred on the outfide to preferve 
 them from rotting. Neither water, vinous 
 fpirits, Oils, acid or alcaline liquors, difiolve 
 or extradt any tindfure from them. In burn- 
 ing, they are fuppofed to emit a peculiar va- 
 pour, which, confined and accumulated in a 
 clofe room, proves poifonous to animals : 
 There are indeed too many examples of fa- 
 tal confequences from the burning of Char- 
 coal in clofe places ; not however from the 
 Charcoal giving out any pernicious matter, 
 but from the quality of the air of the room 
 being altered by the fire. Air that has 
 patted through burning fuel is no longer ca- 
 pable of fupporting either nre or the life o£ 
 animals* 
 
464 
 
 Artificial V egetable ProduElions . 
 
 EMPYREUM ATIC OILS. 
 
 Emp. Oils. 'Y'H E diftillation of empyreumatic Oils is performed in earthen retorts or 
 — _j long-necks, or in coated glafs ones. The fire muft be ftrong, but (lowly 
 Diftillation of ra jf e( ] . an d the jundture of the retort and recipient but (lightly luted. Vege- 
 er ° Oils U m a_ ta, °^ e f u bft ances ' n general, urged haftily by a ftrong fire, emit an aerealelaftic 
 vapour, which, if no exit is allowed it, throws off or burfts the receiver. Re- 
 finous iubflances (well and boil up in the fire: It is cuftomary to mix with 
 thefe a quantity of Sand or other earthy matters to prevent their boiling over, 
 though by carefully regulating the heat, the diftillation may be commodioufly 
 performed without any fuch addition. The Oil which arifes at firft is com- 
 monly fluid, and fwims upon the phlegm and fpirit that preceded it : That 
 
 which follows proves more and more thick and heavy, and fuch as is forced out 
 at laft by the greateft vehemence of fire afiumes a pitchy confidence. 
 
 Their general The Oils obtained from vegetables by this procefs differ remarkably from the 
 properties, efiential ones diftilled with water. Even after their feparation from the fub- 
 cc^ from^ef j e< ^» they do not ar '* re * n the heat foiling water, or at mo ft only the finer 
 fential Oils. and more fubtile parts are elevated by that heat. They have a very difagree- 
 able burnt fmell and tafte, and a great degree of acrimony, without any thing 
 of the peculiar flavour or other qualities of the vegetable they were drawn from. 
 The moll inodorous and infipid exprefied Oils, as Oil Olive and Oil of Al- 
 monds, diftilled by a ftrong fire, become in like manner fetid and acrimoni- 
 ous ; and efiential Oils t'nemfelves, by a like treatment, lofe their fpecific fla- 
 vours, and contrail an empyreumatic taint. 
 
 Empyreumatic Oils difiolve in Spirit of Wine rather more eafily than the 
 efiential [b ) ; they are likewife more difpofed to unite with water, probably from 
 
 their 
 
 (b) Solubility of Oils in Spirit of IVine.] It is 
 obfervable, that the efiential Oils obtained 
 from different vegetable matters, dilfolve 
 with different degrees of facility in Spirit of 
 Wine : That all of them, as firft diftilled, 
 diffolve more eafily than after they have 
 been rectified; and that on every rectifica- 
 tion, or rcdiftillation, they become lefs and 
 lefs diffoluble, whilft the refinous refiduum 
 dilfolves more eafily than the Oil at firft. 
 Exprefied Oils, on the other hand, in their 
 natural date, are not foluble in vinous fpi- 
 rits at all : Diftilled, or rendered empyreu- 
 matic by fire, they acquire a degree of foiu- 
 bility ; and on repeated diftillations they 
 become eafier and eafier of folution. Thefe 
 Oiis are likewife made foluble in fpirit, by 
 being combined with alcaline Salts into Sope, 
 and afterwards feparated from the alcali by 
 the addition of any acid. 
 
 Mr. Macquer, in the French Memoirs 
 
 for the year 1745, endeavours to account 
 for thefe different phenomena— Spirit of 
 Wine, as we have formerly feen, confifts of 
 a fubtile attenuated Oil combined with wa- 
 ter: It contains alfo an acid principle, and 
 poffibly it is by means of this acid that the 
 Oil is combined with the water. The fo- 
 luble efiential Oils are found to participate 
 of an acid ; and the admixture of Oil of 
 Vitriol or Spirit of Nitre renders thofe Oils 
 foluble in fpirit which of themfelves are not. 
 Mr. Macquer is hence led to fuppofe, that 
 Oils are more or lefs foluble, in proportion 
 as they contain more or lefs of a manifeft 
 acid. Efiential Oils, rectified, become lefs 
 foluble by lofing a part of their acid; and 
 the refiduum proves more foluble, by retain- 
 ing the acid which the Oil has loft. Ex- 
 prefled Oils are indiftoluble, becaufe their 
 acid is latent, or too intimately combined 
 with the other principles to exert its acti- 
 vity : 
 
Artificial Vegetable ProduSHons . 465 
 
 their participating more of an acid principle. By careful rediffcillations theyEiwp. Oirs, 
 become more fubtile and volatile, and lofe much of their fetid fmell, a large ^ — rv — 
 proportion of grofs matter being left behind : I have rectified an empyreuma- Re ^ lficatl0IU 
 tic Oil to fuch a degree, that one could not eafily determine what kind of fub- 
 ftance it was : It mingled with aim oft all forts of liquors, with exprefted 
 Oils, diftilled Oils, Spirit of Wine, Vinegar, and Water. 
 
 The fedtification of thefe Oils is ufually performed with the addition of 
 Allies, burnt Hartlhorn, Quick-lime, fixt alcaline Salts, and other fubftances, 
 which are fuppofed to make the purification more perfedl by detaining the groffer 
 matter. There is no occafion for any afliftances of this kind : It is futficient 
 
 to walk the Oil with warm water, put it into a retort with frelh water, diftil 
 by a gradual fire till the fluid part is come over, and repeat the lame procefs 
 with the Oil that diftils : Every repetition renders it more and more fubtile, 
 and proportionably diminilhes its quantity. The water, which arifes before the 
 Oil, is impregnated with a part of it — -—When fixed alcaline Salts are em- 
 ployed in the rectification, a portion ot volatile alcali is generated : When 
 Quick-lime or calcined Hartlhorn, the Oil, by repeated diftillations, is totally 
 deltroyed. 
 
 S O O T. 
 
 Hp HOUGH the fmoke of wood is apparently acid, the Soot has no acidity": Soot 
 1 Inftead of yielding an acid in diftillation, as wood itfelf does, it yields a 1 _» 
 
 volatile alcali ; together with an empyreumatic Oil like that obtained from Its differences 
 vegetables entire. Oils themfeives, whether empyreumatic, eflfential or ex- from vegeta- 
 prefled, afford a Soot in burning-, and this foot is refoluble into the fame pri n - andVrom ch«£r 
 ciples as that of wood. The coal remaining after the diftillation of Soot burnsf mo ke. 
 into v/hite allies, from which may be obtained a fixt alcaline Salt, as from other 
 vegetable allies. Some of the chemifts have ranked Oil as one of the elemen- 
 tary 
 
 fome diredl evidence, that an acid is really 
 extricated from exprelfed Oils, by making 
 them into Sope, or by fire j for the fila- 
 ments of the torn edges of blue paper being 
 ftained of a reddifh-yellow colour by the 
 fumes of boiling Oil, can fcarcely be de- 
 pended on as a teft of acidity. There is 
 wanting more particularly fome proof that 
 thefe Oils are capable of being made diffo- 
 luble in fpirit by the admixture of any vege- 
 table acid ; for their being fo by the concen- 
 trated mineral acids does not feem to be fuf- 
 ficient, efpecially as thefe acids, at the fame 
 time that they render the Oil diffoluble, 
 change its nature, and convert it into a fub- 
 ftance of a different kind. It feems hard to 
 admit that animal Oils contain an acid ; and 
 yet thefe Oils diffolve as well as the vege- 
 table, in Spirit of Wine. 
 
 O Q 
 
 vity : Fire makes them folutrle, and more 
 and more fo, by extricating this acid, and 
 by extricating more and inore of it in every 
 diftillation : Alcalies alfo call forth their la- 
 tent acid and on adding to this compound 
 any other acid, the Oil with its acid fepa- 
 rates (in the fame manner as Sulphur dif- 
 folved in alcalies) and of courfe diffolves in 
 fpirit. The fame theory is applied alfo to 
 refinous fubftances, for all Refins yield a 
 little acid in diftillation : Where he finds a 
 Refin that diffolves eafily in Spirit of Wine, 
 its acid is manifeft or but loofely combined : 
 In thofe which diffolve difficultly, the acid is 
 latent, or enveloped in the other matter. 
 
 This theory is plaufible and ingenious, 
 but a competency of experiments is as yet 
 wanting to enable us to determine how far 
 it is juft. There is wanting, for inftance, 
 
4-66 Artificial Vegetable Productions. 
 
 Soot, tary parts of bodies •, but it cannot furely be looked upon as an element, when 
 i— * v — — > it is convertible or refoluble into an aqueous or acid vapour and Soot, and this 
 Soot further rei'oluble into Water, Oil, volatile Alcali, fixed Alcali and Earth. 
 Differences in The Soots produced from different vegetable fubftances, from green and dry 
 •Soots. ones, from open and more confined fires, differ in regard to the proportion, 
 Analyfis by but not in the quality, of the principles they afford. Sixteen ounces of the 
 fire. common Wood-foot of Berlin yielded a dram of volatile alcaline Salt, feven 
 
 drams of Oil, and a dram and a half of fixed Alcali : The fame quantity of 
 
 French Wood- foot gave upwards of two ounces of Oil, a dram of volatile AI- 
 cali, and four drams of fixed. The volatile Salt is very difficultly purified 
 from the fetid Oil, more fo than thofe of animal fubftances. It is faid that the 
 Oil, rectified with Hartffiorn or Vinegar, acquires a fmell like that of Cam- 
 phor •, but I have not been able, on careful trial, to perceive any fuch fmell. 
 It is obfervable that a mixture of Soot and Salt of Tartar, digefted for fome 
 months with the juice of the Birch-tree, that is, the liquor which iffues upon 
 boring the tree early in the fpring, yields on being diftilled a liquor of a beauti- 
 ful, but not very durable purplifh-red colour: With common water no fuch 
 colour is produced. 
 
 Analyfis by The bitter matter of Soot, and that part in which its ill fmell refides, are 
 menitrua. diffolved and extradfed both by watery and by fpirituous menftrua. On di- 
 
 gefting fixteen ounces of Soot in redtified Spirit of Wine, and evaporating the 
 tindlure, the dry extract amounted to four ounces : The fame quantity, treated 
 in the fame manner with water, yielded juft as much. The Soot remaining 
 after the adtion of either of thefe menftrua, yields with the other about two 
 ounces and five drams. 
 
 Ufes. Soot is employed fometirnes medicinally as an antihyfteric, ific. and in ope- 
 
 rations on fome metallic bodies. It is to the adtion of a footy flame, that the 
 red colour of Minium is owing : From a footy flame, the ruby and fome other 
 glaffes receive their colour. [See pag. 38, 51.] The finer parts, feparated by 
 means of water, are ufed as a Pigment, under the name of Biftre. Boiled with 
 woollen cloth, it communicates a brown dye, and in this intention is fometirnes 
 employed by the dyers. The fubftance called Lamp-black is no other than a 
 vegetable Soot, produced in the burning of Refins. 
 
 F I X T ALCALINE SALTS. 
 
 Ft XT 
 Alcali. 
 
 preparation 
 of fixt alca- 
 Iks. 
 
 1 X T alcaline Salts, called alfo Lixivial falts, are extradled from the affies 
 of vegetables, by macerating or boiling them in water, {training or filtering 
 the Ley, and evaporating it till the Salt remains dry. If the allies have not 
 been thoroughly burnt, the Salt appears brown coloured and foul : By calcina- 
 tion, and rediffolution it becomes pure and white (c). If the folution be eva- 
 porated 
 
 (r) Preparation of fixed Alcahes . ] The moft 
 commodious method of preparing fixed al- 
 caline Salts in the large way feems to be 
 that directed by Kunckel in his Art of 
 Glafs. The afhes of wood or the woody 
 parts of vegetables, either burnt on purpofe 
 
 or as common fuel, are to be put into a 
 large tub or vat, whofe bottom is covered 
 with pieces of fplit wood and flraw to pre- 
 vent the afhes from flopping up the cock. 
 So much water is to be poured on the allies 
 as may totally cover them 1 After Handing 
 \ for 
 
Artificial Vegetable ProduSlions. 
 
 467 
 
 for a night, the liquor, impregnated with 
 their faline part, is to be let off by the cock 
 at the bottom into another veffel ; and the 
 elixation repeated with frefti water fo long 
 as the Ley has any faline tafte. The eli- 
 xated afhes may be ufed, like common 
 wood-afhes, for manure; and the weak 
 Leys may be rendered ffronger, by pouring 
 them, inftead of plain water, upon 3 frefh 
 quantity of afhes. Thus from every parcel 
 of afhes we obtain a ftrong Ley, with a 
 weaker one to be returned on the next. 
 Where the Ley is to be kept in its liquid 
 ftate, wooden veffels (according to him) are 
 more commodious than earthen ones how- 
 ever glazed ; thefe laft being foon corroded 
 and penetrated by the acrid liquor. 
 
 For procuring a folid Salt, the Ley is to 
 be evaporated in an iron pan fixed in 
 brick-work ; frefh Ley being continu- 
 ally fupplied during the evaporation, in a 
 very flender ftream, from a calk placed on 
 the brick-work, till the quantity of Salt is 
 as large as can be conveniently dried in the 
 veffel. This impure brown or blackifh 
 Salt is to be calcined, in a furnace built for 
 that ufe, with a red heat juft not ftrong 
 enough to melt it, and every now and then 
 turned up and ftirred, for fix or feven hours, 
 or till fome of the larger pieces, taken out 
 and broke, appear internally white. Thus 
 we obtain an Alcali fufficiently pure for all 
 the bufinefles in which thefe kinds of Salts 
 are employed : If for particular purpofes a 
 further purification fhould be required, it 
 may be diflolved, infpiflated, and calcined 
 afrefh. The rough Salt lofes, in the firft 
 calcination, commonly about one tenth of 
 its weight. 
 
 Some foak in the Ley a quantity of Straw, 
 Bean-ftalks or other like lubftances, fuffi- 
 cient to imbibe it ; and by drying, and burn- 
 ing thefe, obtain the Salt of the Ley, with- 
 out the trouble of boiling it down. The 
 earthy matter left by the Straw is, in quan- 
 tity inconfiderable, and for many pur- 
 pofes, of no injury to the Salt, particularly 
 for lope-boiling, bleaching, &c. where the 
 Salt is diflolved, and confequently purified 
 from indilToluble earthy admixtures, before it 
 is ufed. There is neverthelefs one great 
 inconvenience in the procefs ; the Straw, 
 when loaded with the Alcali, being very dif- 
 ficultly made to burn. Vegetable fubftances 
 in general, when fully impregnated with 
 
 fixed alcaline Salts, never flame ; and do 
 not burn at all without a continuance of ex- 
 ternal heat; infomuch that fome have pro- 
 pofed the impregnating of wood, for build- 
 ings, with Salts, as an effedlual means for 
 preventing its receiving or communicating 
 fire. 
 
 The ftrength of Leys, or the quantity of 
 Salt diflolved in them, may be eftimated by 
 the weight of a certain meafure of them, 
 compared to the weight of an equal meafure 
 of water ; or more commodioufly, and per- 
 haps as accurately, by means of an hydro- 
 meter graduated from adtual trials with 
 Leys of known ftrength. 
 
 I have made feveral experiments for de- 
 termining the ratio in which alcaline Salts 
 increafe the gravity of water ; with a view 
 to enable the workman to judge with fome 
 precifion, from the weight of the Ley, the 
 quantity of Salt that may be expected from 
 it on evaporation. I diflolved in pure water 
 different proportions of fixed alcaline Salt, 
 and weighed very carefully equal meafures 
 of the feveral folutions, in a narrow-necked 
 glais, which held Sixteen ounces of water : 
 A mark was made in the neck with a dia- 
 mond at the part where this quantity of wa- 
 ter arofe to, and the bottle filled to the fame 
 height with each of the other liquors. The 
 refult of the experiments was as follows. 
 
 When 1 6 ounces 
 of the liquor, 
 by weight, con- 
 tained of Salt, 
 
 The meafure of the liquor 
 weighed more than 16 ounces, 
 or more than an equal mea- 
 fure of water, by 
 
 Oz. 
 
 Dr. 
 
 Oz. 
 
 Dr. 
 
 Gr. 
 
 0 
 
 4 
 
 0 
 
 1 
 
 40 
 
 1 
 
 0 
 
 0 
 
 3 
 
 30 
 
 1 
 
 4 
 
 0 
 
 5 
 
 00 
 
 2 
 
 0 
 
 0 
 
 7 
 
 3 ° 
 
 2 
 
 4 
 
 1 
 
 1 
 
 3 ° 
 
 5 
 
 0 
 
 1 
 
 3 
 
 3 ° 
 
 3 
 
 4 
 
 1 
 
 5 
 
 00 
 
 4 
 
 0 
 
 1 
 
 7 
 
 20 
 
 4 
 
 4 
 
 2 
 
 1 
 
 22 
 
 5 
 
 0 
 
 2 
 
 3 
 
 2 S 
 
 5 
 
 4 
 
 2 
 
 5 
 
 02 
 
 6 
 
 0 
 
 2 
 
 7 
 
 30 
 
 6 
 
 4 
 
 3 
 
 1 
 
 30 
 
 7 
 
 0 
 
 5 
 
 3 
 
 28 
 
 7 
 
 4 
 
 3 
 
 5 
 
 01 
 
 8 
 
 0 
 
 3 
 
 7 
 
 3 ° 
 
 8 
 
 4 
 
 4 
 
 1 
 
 3 ° 
 
 The weights here made ufe of were the 
 Troy, of iixty grains in the dram, and 
 eight drams in the ounce, 
 o z 
 
 Fixt 
 Alcali. 
 k , — ~J- 
 
 Thefe 
 
4 6S 
 
 Artificial V ege table ProduElions. 
 
 Fjxt porated only till a pellicle begins to concrete upon the furface, then put into 
 Alcali. a glafs body, covered lb as to prevent the falling in of duft, and fet by in a 
 ■ ■— v“— ^ moderately warm place, part of the Salt will fhoot into cryftals ; and if the re- 
 maining liquor be further evaporated to a pellicle, and fet by as before, more 
 cryftals will be obtained. Some have held thefe cryftallized Salts to be more 
 pure than fuch as are diredtly inlpiflated to drynefs : But in reality they are 
 
 more impure; fixed alcalies never affuminga cryftaliine form, but in propor- 
 tion as they participate of an acid. If a perfect Alcali is required, we fhould 
 rejedt the cryftals, and employ only the Salt procured by infpiffation from the 
 liquor remaining after the cryflallization. 
 
 FiXt alcaline Salts were originally prepared from the afhes of the plant Kali, 
 and from hence they are fuppofed to have received their name. Kali or Soda 
 is a maritime plant ; and its afhes contain, befides the truly alcaline Salt, a 
 portion of Sea-falt (d). It has been found that fixed alcalies are conftantly the 
 fame, whatever fubject they have been produced from : Hence at prelent, they 
 
 are 
 
 Different 
 
 forts. 
 
 Soda, 
 
 Thefe experiments agree very nearly in 
 the fame ratio. We may draw from 
 them this general rule, that the weight, by 
 which any meafure of Ley exceeds the fame 
 meafure of water, is fomewhat lefs than one 
 half (or about five twelfths, of the quan- 
 tity of Salt contained in a meafure of the 
 Ley. 
 
 (A Soda.] Soda, the impure Salt of Kali 
 or Glafswort, fometimes brought to us from 
 Spain, appears to contain no acftual marine 
 Salt, or only an inconfiderable proportion. 
 The faline part however, when purified 
 from the earthy matter which is ufually in 
 large quantity, approaches in fome refpefts 
 to the nature of that Salt, and differs re- 
 markably from all the other known vege- 
 table alcalies. 
 
 On gently evaporating folutions of it, the 
 Salt concretes into cryftaliine maffes, which 
 do not liquefy, nor foon grow moift in the 
 air. The cryftals change Syrup of Violets 
 green, render Sulphur and Oils foluble in 
 water, effervefce with all acids, precipitate 
 earthy and metallic bodies diffolved in them, 
 and unite with the acid into a neutral Salt ; 
 proofs, that notwithftanding their cryftal- 
 line appearance, they are truly alcaline. 
 
 When this Alcali is combined with the 
 acetous acid, the neutral compound is found 
 to be nearly fimilar to that compofed of the 
 fame acid and the common alcalies ; but in 
 combination with the mineral acids, the cafe 
 is different. With the vitriolic it forms, 
 
 not like other alcalies a vitriolated Tartar, 
 but a Sal mirabile ; with the nitrous, not 
 common Nitre, but a Nitre which cryftal- 
 lizes into cubes ; with the marine, a perfect 
 Sea-falt; proofs, that the Alcali of Soda is 
 the fame with the alcaline bafis of Sea-falt, 
 hut wants its acid. (See the refpective 
 Saks in the firft part). 
 
 The Kali itfelf appears to contain aftuai 
 Sea-falt. Stahl informs us, that its tafte is 
 manifeftly brackifh, and that in fome places 
 it is ufed inftead of common Salt. HenckeJ, 
 inthe Appendix to his Flora J'aturnizam , gives 
 a more convincing proof : By boiling the 
 herb in water, and evaporating and cryftal- 
 lizing the decodtion, he obtained a true ma- 
 rine Salt, and in confiderable quantity. 
 
 The laft mentioned author difcovered a 
 pretty remarkable phenomenon in treating 
 both the Spanifh Soda, and the Salt elixated 
 from the afhes of the German jointed Kali, 
 with the mineral acids. On faturating 
 either of thefe Salts with any of the acids, a 
 deep blue powder fell to the bottom, fimilar 
 to Pruffian-blue, and which anfwered equal- 
 ly in painting. He obferves, that the quan- 
 tity of this powder is very final] , amounting 
 only to about five grains from an ounce of 
 the Salt; and that it is largeft when the vi- 
 triolic acid is ufed: That with diftilled Vi- 
 negar there was no precipitation ; with dul- 
 cified Spirit of Nitre, only a brownifh one. 
 
 The Spanifh Soda was formerly in great 
 requeft for making Glafs. Kunckel ob- 
 ferves, that when duly purified, it proves. 
 
 for 
 
Artificial V egetable Productions. 469 
 
 are made chiefly from fuch fubjedts as are moft plentiful, and afford them Fixt 
 in greatelt purity and in greateft quantity. A Salt is dill indeed in form- Alcai.i. 
 
 places prepared from Kali, and employed by the glals makers, dyers and — .4; j 
 
 lope-boilers; but thofe commonly met with in the Ihops, under the name of 
 Pot-afli, are obtained from the allies of different kinds of wood, particularly pot-afli. 
 the hard ones : Tfiey are made chiefly in the woody countries, Mufcovy, Po- 
 land, Courland; &c., 
 
 The common Pot-afli is not a pure alcaline Salt, any more than the Salt of 
 Soda. It contains a conliderable portion of mere earth, feparable by dillblv- 
 ing the Salt in water (e). It contains alio a neutral Salt, whole acid is mani- Contain a 
 feltly the vitriolic, for on being melted with powdered Charcoal, it produces a neutra l Sait, 
 true Sulphur. Did this acid exill originally in the wood ? Was it communi- 
 cated, during the burning, by the air, whole palfage through the fuel is ablo- 
 lutely neceffary to the fupport of fire, and of which immenfe quantities muft 
 
 be 
 
 for'that purpofe equal, but not fuperior to 
 other alcaline Salts ; that Glals made with 
 Soda in the impure ftate in which it is 
 brought over, is exceeding apt to crack or 
 fly in cooling, and has likewife a bluilh call, 
 which, if we endeavour to clear it by the 
 additionofManganefe, changes to a blackilh 
 or a greenilh — Stahl on the other hand, 
 gives the preference to Soda. He admits 
 that Pot-afli yields a finer Glafs ; but fays 
 the Glafs prepared with Pot-alh has this ca- 
 pital defedt, that if it has not been kept in 
 the fire till the Salt is burnt dead as he calls 
 it, velfels made of it crack after they have 
 been wetted, and large pieces fly out of 
 them ; the unmortified or unconfirmed Salt 
 beginning to dilfolve, fo as to deftroy the 
 cohelion of the Glafs. W e apprehend that 
 this imperfedtion proceeds rather from a re- 
 dundance in the quantity, than from any 
 particular quality of the Salt made ufe of. 
 
 ( e ) Pot-aJh.~\ There are two principal forts 
 of thefe Salts brought chiefly from Ger- 
 many, Pearl-afh, and Pot-afh. The Pearl- 
 alh is either of the whitifh Pearl colour 
 from which it receives its name, or exter- 
 nally of a bluifh call, which thefe kinds of 
 Salts are apt to receive in- calcination from 
 the contadt of any inflammable matter. 
 Both the Pearl-allies are tolerably pure al- 
 caldes : Diflolved in water, or deliquiated 
 in the air, they leave only a fmall quantity 
 of earthy matter, fcarcely more than every 
 alcaline Salt does upon repeated folutions- 
 and calcinations. They are fometimes, 
 .however adulterated with heterogeneous fa- 
 
 line matters, particularly Sea-fait. The 
 purity of Pearl-alh from fubftances of the 
 earthy kind points out the method in which 
 it has been prepared, namely, evaporating 
 a Ley of vegetable allies till the Salt re- 
 mains dry. 
 
 Pot-alh is a much more impure faline 
 mafs : That called Ruffia or Mufcovy Pot- 
 alh is accounted the heft. This is of w 
 dark colour, confiderabiy hard, and does not 
 eafily grow moift in the air : On boil- 
 ing it in water, a quantity of earth remains 
 undilfolved, much larger than that of the 
 Salt which is extradted. It is neverthelefs 
 found to be ftrongly alcaline, to be more 
 * pungent to the tafte,. to faturate more acid, 
 and more powerfully to dilfolve Oils, than 
 the purer alcaline Salts : Plence it is pre- 
 ferred by the So'pe-boiler. 
 
 This Salt is faid to be prepared, by burn- 
 ina: wood with a clofe fmotherinp; heat ; 
 making a Ley from the coarfer part of the 
 allies, and moiftening therewith the finer 
 part into the confiftence of a pafte, ftratify- 
 ing this pafte with fome of the more inflam- 
 mable kinds of wood, and fetting the pile 
 on fire — It is not improbable, that the fa- 
 line and earthy part of the allies would thus 
 run together into- hard lumps'; but a mafs 
 pofielling the adtivity of RuffiaPot-alh is not 
 to be obtained by any procefs of this kind. 
 For the difeovery of the ingredient on which: 
 that quality depends, we are obliged to Dr. 
 Home, who, in his eliay on bleaching, has 
 proved, by a number of curious experi- 
 ments, that Ruftia Pot-alh contains a large, 
 admixture of Quick-lime.. 
 
4?o 
 
 Artificial Vegetable Productions. 
 
 Fixt 
 
 ALC ALT. 
 
 Purification 
 
 Differences in 
 the common 
 alcalies. 
 
 All fimilar 
 when pure. 
 
 be confumed by the large piles ufually burnt at once for the making of Pot- 
 afh ? Or was it imbibed from the water employed for the elixation of the 
 Salt ? Perhaps it may proceed in part from all the three iources. 
 
 The neutral Salt in Pot-afh, whatever be its origin, is fimilar in its proper- 
 ties to vitriolated Tartar. (See page 190.) Itisfcarcely abled upon by cold 
 water, diffolves difficultly in hot water, and in great part feparates again as the 
 foiution cools. Hence the alcaiine Salt may be purified from the neutral, by 
 folution in hot water, and after evaporation to a pellicle, fetting the liquor to 
 fhoot ; or more effectually, by employing cold water, which will diffolve the 
 alcaiine, and leave the neutral Salt behind. The purification will ftillbemore 
 perfect, if the infpiffated Salt be run per deliquium, for no part of the neutral 
 Salt will deliquiate in the air. 
 
 It is owing to the admixture of this vitriolic or other neutral Salts, or to a 
 part of the inflammable or oily principle of the fubjeCt being retained in the 
 Salt, from the allies not having been perfectly burnt ; that different alcaiine 
 Salts, exhibit in fome experiments, different phenomena. Hoffmann obferves," 
 that when Oil of Vitriol is poured upon Salt of Tartar, the liquor acquires a 
 blackifh fkin on the furface, appears itfelfalfo blackifh, and emits a particular 
 fetid fmell ; but that nothing of this happens when Pot-afh is ufed ; that Salt 
 of Tartar, melted with fand, does not form a clear and tranfparent Glafs, which 
 Pot-afh does 5 and that Salt of Tartar gives a tinClure to highly rectified Spirit 
 of Wine, which Pot-afh does not. Thefe experiments prove, not that the two 
 Salts differ from one another as alcalies, but that one retains a part of the Oil 
 of the fubjeCf, and the other not. When Tartar is deflagrated with a due pro- 
 portion of Nitre, its Oil is wholly burnt out, and the alcaiine Salt thus ob- 
 tained, equally with Pot-afh, forms a clear Glafs with fand, produces no black- 
 nefs with Oil of Vitriol, and gives no tinClure to rectified fpirit. The fame 
 author finds however that there is now another difference •, that Pot-afh, and 
 the Salt made from Tartar alone, on being melted with Charcoal powder, form 
 a fulphureous compound, whilft the Salt from Tartar and Nitre has no fuch 
 effeCt: The caufe is obvioufly this, that the two former contain a portion of 
 the vitriolic Salt above-mentioned, and the latter not. 
 
 In (hr rt all the alcaiine Salts, when perfectly pure, are one and the fame 
 thing : From one vegetable we obtain Salts as different, according as the allies 
 have been more or leis calcined, elixated with hot or with cold, with a large 
 or a fmall quantity of water, &c. as we do from different ones •, the differences 
 obferved in the Salts, where any differences are obferved in them, depending 
 upon the manner in which the procefs has been managed, and not upon the 
 qualities of the fubjeCt. No art can diflinguifh the fixt alcaiine Salts of the 
 fweet plants from thofe of the bitter or the four ; of the purgative from the 
 aftringent; of the highefl: cordials and aromatics from thofe of the molt deadly 
 poifons (/). 
 
 Fixt 
 
 (/) Identity of fixed alcaiine Salts. ] In re- mon ufes, by incinerating the plant, elixat- 
 gard to this point, fixed alcaiine Salts are to ing the Salt from the afhes, and evaporat- 
 be confidered in two ftates ; that in which ing the Ley ; and that of their ultimate pu- 
 they are prepared by the workman for com- rity, obtained by repeated calcinations with 
 
 a ftrong 
 
Artificial V egetable Productions . 
 
 47 1 
 
 Fixt alcaline Salts feern to be produced from a combination of the grofier acid 
 and a part of the earth of the fubjeft, and perhaps a little of the more fixed inflam- 
 mable principle, effected by the fire. The effential Salt of Sorrel is a truly acid Salt, 
 totally foluble in water. An ounce of this Salt, diftil led in a giafs retort, gave 
 over about a fcruple of Oil, and three drams of phlegm (lightly impregnated with 
 a volatile acid, certainly not all the acid that the Salt contained : The refiduum 
 weighed four drams twenty grains, and from this were obtained three drams of 
 perfedt alcaline Salt, If fixed alcalies be calcined, deliquiated in the a;r, the 
 liquor infpiflated, and the deliquiation and infpiffation ieveral times repeated, 
 a quantity of earthy matter will feparate every time, till at length nothing but 
 earth is left. The perfect infpiffation, however, cannot be continued long: 
 After a number of repetitions, the liquor cannot be reduced to a dry ftate, but 
 retains nearly the confiftence of Oil of Vitriol: Expoled to the fire in a cru- 
 cible, it diffolves or penetrates it. 
 
 Vegetable fubftances which abound moft with acid, are thofe which yield 
 moft fixed Alcali; and thofe from which no acid is feparable by diftillation, 
 are thofe which yield no fixt alcaline Salt. When vegetables that do abound 
 with acid are burnt with a dole fmothering heat, greateft part of the acid is 
 
 gradually 
 
 Ft XT 
 
 A 1 . C A I. f . 
 
 Their pro- 
 duction.. 
 
 a ftrong fire, and deliquiations in the air. 
 In this laft frate, all fixed alcaline Saits (the 
 marine alcali excepted) are perhaps one and 
 the fame thing ; at leaft the experiments 
 hitherto made difcover no diverfity in them. 
 But in the firft ftate, the Salts of different 
 plants exhibit, on i'undry trials, differences 
 too confiderable to be overlooked by the 
 artift or by' the philofopher. 
 
 Mr. Gmelin has given a great number of 
 experiments on this fubject in the fifth vo- 
 lume of the Commentaria Petropolitana. The 
 Salts of the feveral plants examined were 
 prepared with great care, and all of them 
 exacfly in the fame manner, each vegetable 
 being burnt, in a feparate crucible, with the 
 fame degree of fire, till no remains of coaly 
 matter could any longer be perceived ; and 
 the allies elixated in giafs veffels, with cold 
 diftilled water. The Salts, thus obtained, 
 were found to produce different colours on 
 mixture with certain liquors, and to effer- 
 vefce in very different degrees with acids : 
 Certain metallic folutions were by fome 
 precipitated, by others only rendered thick, 
 by others both precipitated and thickened, 
 whilft others occafioned neither one or the 
 other of thefe changes, and left the liquor 
 fluid and tranfparent. Thus, with the vi- 
 triolic acid, the Salts of Southernwood and 
 Sage ftruck a pale brown colour thofe of 
 Pine-tops and Rue, a yellow ; that of Fern, 
 a reddifh-yellow j and that of Sanicle, a 
 
 dark Leek green: That of Dill wielded a 
 Leek green Precipitate, with elegant green 
 flakes floating in the liquor. This laft Salt 
 gave a greenifh Precipitate alfo with the ma- 
 rine acid, and a red one with the nitrous. 
 Solution of corrofive Sublimate was changed 
 yellow by Salt of Southernwood ; of a 
 brownifh Saffron colour by that of Coitf- 
 foot ; of a deep red by that of Wormwood ; 
 and of a Pitch colour by that of Dill : That 
 of Fern threw down an opal coloured, of 
 Sage a Sulphur yellow, of Elder-flowers a 
 Citron yellow, of Sanicle a Saffron colour- 
 ed, and of Milfoil a deep red Precipitate. 
 From folution of Silver, Salt of Carduus. 
 benediftus threw down a white, of Camo- 
 mile a grey, of Hyffop a brownifh, of Dill 
 a blackifh-brown, of Scabious a yellovvifh^ 
 and that of Pine-tree tops a Sulphur yellow 
 Precipitate. Solution of Vitriol of Copper 
 was changed by Salt of Southernwood to a 
 bright fea-green, by that of Dill to an un-» 
 lightly green, of Agrimony to a greemfh- 
 blue, and by that of Milfoil to a bright fky- 
 blue: The Salt of Pennyroyal made the 
 liquor thick as well as blue, and that of 
 Feverfew made it thick and green: The 
 Salt of Hyffop threw down a green Precipi- 
 tate, that of Scurvygrafs a blue one, and 
 that of Fumitory a greenifh blue; whilft 
 the Salt of Fern made fcareely any change; 
 either in the colour or corJuftency of the 1.L 
 cquor. 
 
472 Artificial Vegetable Productions. 
 
 Fixt gradually diffipated, and very little Alcali is produced : In a quick open fire, 
 Alcali. the acid is intimately coagitated with the earth before the diffipation can hap- 
 u.— - v— — > pen, and the produce of Alcali is vaftly larger : What a minute proportion 
 does Charcoal yield, compared to that obtainable by burning the wood at firft 
 in an open fire ! Rotten wood affords little or none. 
 
 That the oily matter of the fubject contributes alfo to the formation of the 
 Alcali, either by furnifhing a material principle to the compound, or by ferv- 
 ing, when on fire, as a medium for the coagitation and combination of the 
 acid with the earth, appears from hence, that no alcalies are producible but 
 from fubftances that contain Oil, and by feparating their Oil we diminiffi their 
 produce of Alcali, though not fo much as by feparating their acid. From 
 ftxty- four ounces of dry Wormwood were obtained about two ounces and a 
 half: The fame quantity, digefted in Spirit of Wine fo long as the menftruum 
 continued to extraft any tindure, yielded but one ounce ; and when digefted in 
 water as well as in fpirit, only nineteen or twenty grains. 
 
 Whether ob- Tachenius and feveral others affirm, that plants burnt whiift frefh, afford 
 tained in much more Salt than if they are previoufly dried : Rivinus, on the other hand, 
 greatetlquan-f oun d from experiment, that the yield was in both cafes the fame. Both thefe 
 or 'd r y 0 plants- ° b fe r v a t i o n s are in certain circumftances juft, but neither of them univerfally 
 fo. In fome vegetables, the acid principle is of a iubtile volatile kind, or 
 loofely blended with the other parts, fo as to exhale in drying : In others, it 
 is grofter or more intimately combined, and fuffers no wafte in the exficcation. 
 The firft yield moft Alcali if burnt frefh ; the latter yield juft as much when 
 
 dried Some vegetables, however carefully burnt, lofe their acid in the pro- 
 
 cefs, and afford very little Alcali : Guaiacum wood for inftance. Neverthelefs, 
 if an extraft be made from Guaiacum with water, and this extraft gently burnt 
 along with the remaining wood, the affies thus obtained will yield on elixation 
 a confiderably larger quantity (g). 
 
 Their diftin- Fixed alcaline Salts are diftinguiffied from faline fubftances not alcaline, by 
 guifhing cha- thejr effervefeing with all acids, forming with them neutral Salts, precipitating 
 rafters . folutions made in acids, and changing Syrup of Violets green. They are di- 
 
 ftinguiffied from volatile alcalies by their fixity (b) and fufibility in the fire, by 
 
 their 
 
 (g) More Alcali from the extraU^ &e.] Mr. 
 BourdelLne informs us (in the Memoirs of 
 the French Academy for the year 1730) that 
 this experiment fucceeded with him in a 
 different manner. Six pounds, he fays,, of 
 {havings of Guaiacum gave one hundred 
 and thirty grains of fixed alcaline Salt : 
 The fame quantity, after having been boil- 
 ed in water for twelve hours, gave feventy- 
 eight grains; the decoAion, infpiifated and 
 calcined, only forty- feven grains; fo that 
 here, the extraA and the remaining wood 
 did not yield fo much as the fame quantity 
 of the wood burnt direAly. But it muff 
 be obferved, that our author requires the 
 ■extra A and the remaining wood to be burnt 
 1 
 
 together , whereas Mr. Bourdeline burnt them 
 fieparately. The fire is required alfo to be 
 gentle ; a circumftance which does not a little 
 influence the produce of the Salt, and which 
 in this experiment was not perhaps attended 
 to. I cannot however take upon me to de- 
 termine whether the yield is largeft in one 
 or the other cafe. 
 
 ( h ) Fixity in the fire.'] Though thefe Salts, 
 by themfelves, bear a confiderably ftrong 
 fire, without any remarkable diffipation, 
 and give over nothing on being diftilled in 
 clofe veffels, they are far from being abf'o- 
 lutely fixed. They evaporate plentifully in 
 the giafs-houfe furnace; and by the admix- 
 ture 
 
Artificial Vegetable ProduSUom. 473 
 
 their deliquiating in the air and never afluming a cryftalline form, changing Fjxt 
 folution of Mercury-fublimate not white but of an orange-yellow, producing Alcalt. 
 no blue colour with Copper or its folutions, railing no vifible cloud when v— 
 placed near an unftopt bottle of Spirit of Nitre, occafioning no coldnefs but 
 rather heat on being difiolved in water. Pure fixed alcalies, difiolved in water, 
 mingle with a folution of any other pure Alcali, without the leaft precipitation, 
 turbidnefs, or fenfible change. 
 
 Fixt alcalies difiolve Sulphur, Oils, Fats, and refinous bodies. By Quick- Co n fid ere d as 
 lime their activity is increafed ( i ), and in this fiate they difiolve fome metallic menftrua, 
 fubftances, as Calces or filings of Lead, fine filings of Copper, Copper preci- 
 pitated 
 
 ture of certain other fubftances they are in 
 part volatilized in a very gentle heat ; in a 
 heat no greater than that in which rectified 
 Spirit of Wine diftils, and the volatile Al- 
 cali of Sal ammoniac fublimes. In effect, 
 when Spirit of Wine is rectified by diftilla- 
 tion from fixed alcalies, it always carries up 
 with it a portion of the Alcali ; and when 
 the volatile Salt of Sal ammoniac is extri- 
 cated from its acid by the fame interme- 
 dium, it elevates in fublimation a much 
 larger quantity: See page 221. 
 
 (z) Activity increafed by .^htickAimeJ] For 
 this purpofe, equal parts of Quick-lime and 
 fixt alcaline Salt are gradually fprinkled 
 with fo much water as will flake the Lime : 
 More water is then added, the whole ftirred 
 together, and fuftered to Hand for a day or 
 two. The liquor, poured oft* clear from the 
 undifiolved Lime, is the common Sope-ley. 
 The College of London direct their Ley, 
 for making their Almond Sope, to be of 
 fuch a ftrength, that an exadt wine-pint 
 may weigh juft fixteen ounces troy : If it is 
 heavier, for every dram that it exceeds this 
 weight, an ounce and a half of water, by 
 meafure, is to be added to each pint of the 
 liquor : If lighter, it is to be boiled till the 
 like quantity is wafted, or poured upon frelh 
 Lime and afhes. The Sope-boilers make 
 their Ley confiderably ftronger : A wine- 
 pint commonly weighs above feventeen 
 ounces, or about one eighth more than a 
 pint of water. 
 
 As thefe Leys are much more acrimoni- 
 ous, and more active menftrua, than foluti- 
 ons of fixed alcaline Salts by themfelves ; 
 they retain alfo a proportionably greater de- 
 gree of a&ivity, when evaporated to a dry 
 Salt. The Salt is fo corrofive, as not to be 
 
 P 
 
 fafely touched with the tongue : Applied to 
 the fkin, it quickly produces a folution of 
 continuity, and hence is commonly made 
 ufe of as a Cauftic. Some prepare the Cau- 
 ftic by adding a quantity of Lime in fub- 
 ftance towards the end of the evaporation 
 of the Ley : This addition renders it lefs 
 apt to liquefy and fpread upon the fkin, but 
 at the fame time lefs fpeedy in its effedt. 
 
 Experiments have not difcovered, that the 
 cauftic Salt retains any part of the Lime 
 made ufe of in the preparation of the Ley : 
 The Alcali does not gain, but on the con- 
 trary fufFers a notable diminution of its 
 weight j as if the increafe of its activity was 
 owing not to any thing fuperadded by the 
 Lime, but to fome particular matter being 
 leparated by it. 
 
 Some imagine that the Lime extricates a 
 grofs earth from the Alcali, and in the room 
 thereof fubftitutes its own more fubtile and 
 acrimonious matter. The earth, which 
 precipitates upon mixing a purified folution 
 of fixed alcaline Salt with Lime-water, is 
 alleged in proof of this opinion : But that 
 earth appears to be the Lime precipitated by 
 the Alcali, and not a part of the Alcali pre- 
 cipitated by the Lime : Calcined by a ftrong 
 fire, it returns into Quick-lime. 
 
 Dr. Black, in the phyfical and literary 
 efiays publifhed by a fociety at Edinburgh, 
 has advanced a new theory, which he hat- 
 endeavoured to eftablilh by a number of 
 experiments Fixed alcaline Salts, ac- 
 
 cording to this gentleman, contain a large 
 quantity of air fixed or imprifoned in them : 
 The effervefcence, whiph arifes upon mixing 
 them with acids, is no other than a tumul- 
 tuary difcharge of this air. Cauftic alca- 
 lies, he finds, make no effervefcence with 
 acids, a proof that thefe alcalies have loft 
 3 p their 
 
474 
 
 Fixt 
 
 Alcali. 
 
 V *- ' 
 
 Combinati- 
 ons of them 
 with acids. 
 
 Artificial V egetable ProduEHons. 
 
 pitated from blue Vitriol, the Copper in Verdegris, Tin, andRegulus of An- 
 timony : This laft they corrode into a calx, which by force of fire may be 
 melted into an amber-coloured Glafs. There are two ways of obtaining i’olu- 
 tions of Iron in thefe Salts : One, by dropping a folution of the metal made in 
 Aqua fortis into a ftrong alcaline Ley, the acid will be abforbed and neutra- 
 lized by a part of the Alcali, and the Iron remains dilTolved by the reft : The 
 other is, by deflagrating Iron-filings with Nitre; the acid of the Nitre will be 
 diflipated in the deflagration, and great part of the Iron will diffolve in water 
 along with the remaining Alcali. (See page 73.) Thefe Salts, combined 
 with Sulphur, diffolve almoft all the metals and femimetals, Gold itfelf not 
 excepted. When made fluid by a ftrong fire, they diffolve Flint, Sand, and 
 other earthy bodies, and on cooling concrete with them into a mals, which 
 proves diffoluble in water or an indiffoluble Glafs, according as the propor- 
 tion of the earth is large or fmall. Added to phlegmatic fpirits, either 
 of the inflammable or volatile urinous kind, they imbibe the redundant 
 phlegm, and thus render the fpirit more concentrated. In pure vinous fpirits 
 they do not diffolve, or only in very fmall quantity, fufficient however to give 
 a fenfible acrimony or alcaline impregnation to the fpirit. If both the Spirit 
 and the Salt are pure, the liquor receives no colour; but if any oily or refin- 
 ous matter be previoufly diffolved in the fpirit, or if the Salt be impregnated, 
 though (lightly, with inflammable matter of any kind, a confiderably deep 
 tin&ure will be produced. Fixt alcalies in general heighten the colour of ve- 
 getable and animal tinctures, whether drawn with water or with fpirit ; but 
 they commonly vary the tafte, and often debafe the fmell of the preparation. 
 
 They form with acids different neutral Salts according to the nature of the acid 
 employed ; with the vitriolic, a bitterifh Salt, very difficult of folution in water, 
 and not fufible in the fire, commonly called vitriolated Tartar, the alcaline 
 Salt made from Tartar being that which has chiefly been employed for thefe 
 purpofes ; with the nitrous acid, they form a perfedl Nitre ; with the marine, 
 a Salt greatly refembling Sea lair, but not perfectly the fame, the alcaline bafis 
 of Sea-lalt being in fome refpe<fts different from the common vegetable alca- 
 lies. They readily cryftallize with any of the mineral acids, and with Tartar; 
 with which laft they compofe a neutral Sait, much eafier of folution than the 
 Tartar itfelf, and hence called foluble Tartar. They do not eafily cryftallize 
 with the acid of Vinegar or Lemon juice; thefe mixtures, if by careful ma- 
 nagement reduced to a cryftalline form, foon deliquiate again in the air. 
 
 There 
 
 their air ; and from the lofs of this princi- 
 ple he deduces their caufticity. Expofed 
 long to the atmofphere, they become latu- 
 rated with air afrefti, and are now found to 
 be mild again and to effervefce like the plain 
 alcalies. The cafe is the fame in regard to 
 Quick-lime: Chalk and other calcareous 
 earths abound with air, and effervefce 
 flrongly with acids : By whatever means 
 this air is expelled, they become Quick- 
 lime (which makes no effervefcencej and by 
 whatever means their natural quantity of 
 
 air is reftored, they return to their natural 
 inactivity. Quick-lime abforbs air from 
 fixed alcaline Salts : Hence in the prefent 
 procefs, the Salt is acuated, and the Lime 
 rendered inert. When Chalk, diffolved in 
 acids and thus diverted of its air, is precipi- 
 tated by Cauftic alcalies which have no air 
 to communicate, he finds the Precipitate to 
 be a true Quick-lime ; whereas, when the 
 precipitation is made by plain alcalies, the 
 Chalk, imbibing their air, returns to an 
 indolent earth. 
 
Artificial Vegetable ProduSlions . 475 
 
 There are different ways befides immediate mixture, of obtaining combina- ^ IXT 
 tions of fixt alcalies with acids, depending upon their great affinities with one -A-Lcalt. 
 another. Thus, (i.) When any metallic body is diffolved in an acid, the add i- 
 tion of an alcalineSalt precipitates the metal: If the remaining liquor be fil- t j es wit k 
 tered and evaporated, it leaves a neutral Salt compofed folely of the acid and acids, 
 the Alcali. Some of the metals fuffer a notable alteration in this procefs : 
 
 Thus the calx oflron precipitated from the vitriolic acid in making vitrioiated 
 Tartar, is fcarce at all revivable into malleable Iron again. (2.) When acids 
 are combined with volatile alcalies into ammoniacal Salts, and this compound 
 mixed with a fixt Alcali ; on expofing the mixture to the aCtion of a moderate 
 fire, in a retort or other convenient veffel, the volatile Alcali ariles, and the 
 acid remains combined with the fixed: If it was not for the intervention of the 
 fixt Alcali, it would fublime in conjunction with the volatile. (3.) In like 
 manner, when Sulphur, or Oils, or Refins, are diffolved by a fixt Alcali, the 
 addition of any acid will feparate the fubftance before diffolved, the acid and 
 the Alcali uniting together; and even when both of them are previoufly fatu- 
 rated, the Alcali forinftance with Sulphur, and the acid with metal, on mix- 
 ing the two folutions together both the Sulphur and the metal fall, leaving only 
 the Alcali and the acid combined in the liquor. (4.) When the Alcali is pre~ 
 vioufly combined with one acid, the addition of a more powerful acid will 
 break the union and difengage the Alcali from the firfl acid. On the neutral 
 Salt compofed of fixed Alcali and Vinegar, pour fome Spirit of common Salt : 
 
 The acetous acid will inftantly begin to exhale, and on applying a moderate 
 heat will be totally diffipated, leaving the Alcali combined with the marine 
 acid. Add to this combination a due proportion of the nitrous acid, and 
 the marine will be expelled, and a perfect Nitre remain. The vitriolic in 
 like manner expels the nitrous, and takes poffeffion of the Alcali in its place : 
 
 This being the molt powerful acid, is not to be diflodged by any other. 
 
 When this acid is combined with inflammable matter into Sulphur, it lofes 
 its great affinity to alcalies. If the neutral Salt, compofed of the vitriolic acid 
 and fixed Alcali, be melted with powdered Charcoal, the refult is a mixture of 
 Alcali and Sulphur. On diffolving this compound in water, the flighteft even 
 of the vegetable acids precipitates the Sulphur and unites with the AdcaJi. 
 
 Stahl, who firfl difcovered the production of Sulphur by melting vitrioiated 
 Tartar with Charcoal, propofed a problem to me, “ to feparate the acid of 
 “ vitrioiated Tartar, inflantaneoufly, and in the palm of the hand.” Being 
 at Paris in 1715, I propofed the fame problem to the elder Geoffroy, and two 
 years after appeared his Memoir, in which he endeavours to give a folution of 
 it. He has not however hit the point, his procefs being no other than that 
 publifhed by Stahl for making Sulphur, namely fufion in a crucible and precipi- 
 tation with acids. The true folution is this : Lay on the hand a coal not tho- 
 roughly ignited ; drew upon the burning part fome vitrioiated Tartar, blow it 
 a little, and the acid will inftantly feparate and leave the Alcali (k). 
 
 Fixt 
 
 (k) Problem of Jeparatitig the add of vitrioiated author’s folution given above, the fepara- 
 Tartar.] Another folution of this problem tion, though it cannot be fa id to be per- 
 il as been mentioned in page 17 2. In the formed immediately on the palm of the 
 
 P p p 2 ' hand, 
 
476 Artificial V egetable Produ&ions . 
 
 Fixt Fixt alcalies combined with a little Oil, have their pungency proportionably 
 
 Alcali. covered (k) : With a larger quantity, they form Sope. Impregnated by calcina- 
 
 ' tion with an empyreumatic animal Oil (/), they acquire Angular qualities which 
 
 With inflam- have not hitherto been fufficiently examined : Thus, from a folution of green 
 
 mable fu - Vitriol and Alum, they precipitate the fine blue Fecula called Pruffian-blue. 
 ltances. ' * *■ 
 
 S O P E S. 
 
 Sop es. X HE fi ne hard white Sopes are made with Oil Olive, and an Alcali acuated 
 «_ ' \ with Quick-lime, which promotes the aftion of the Salt upon the Oil, and at 
 
 the fame time difpofes the Sope to a hard and dry confidence, which it does not 
 eafily affume when made with plain Alcali. I have tried to prepare Sope with 
 alcaline Ley alone, and with Lime-water alone : With the firft, the Sope 
 turned outfoftifh and un&uous : With the latter, I obtained, not a true Sope, 
 but a hard brittle compound, from which the Oil feparated on trying to 
 dififolve it in water. A quantity of common Salt is generally added in the 
 procefs, but it does not enter the compofition of the Sope : The ufe of this 
 Salt is, when the Oil has been incorporated, by boiling, with the alcaline Salt 
 of the Ley, to promote the feparation of the faponaceous concrete from the 
 water: It is only at this period that the Sea-falt is added. The Sea-falc may 
 be recovered from the remaining liquor by cryftallization •, if any part of it 
 happens from unlkilful management, to be retained in the Sope, it feparates in 
 little cryftals as the Sope dries. 
 
 The 
 
 hand, is the moft perfect and apparent, only 
 the acid being diflipated, and the Alcali 
 left by itfelf pure. 
 
 (/ 5 ) Pungency covered by Oil.] Hence fome 
 have endeavoured to improve the prepara- 
 tion of fixed alcaline Salts for medicinal ufe. 
 Inftead of burning out all the Oil of the 
 vegetable by thorough calcination of the 
 afires in an open fire, fo as to obtain a pure 
 Alcali ; they endeavour to retain in the 
 Salt as much as poffible of the Oil, by 
 flowly incinerating the fubjedt with a clofe 
 fmothering heat. Thefe oily alcalies, or 
 medicated Salts, as they are called, are of a 
 brown colour, and in tafte much lefs acri- 
 monious than the purer white alcalies. 
 
 (/) Fixt alcaldes impregnated with animal Oil.] 
 This impregnation is effected by mixing 
 pure fixt alcaline Salt with twice its weight 
 of ox-blood evaporated to drynefs and re- 
 duced into powder ; and calcining the mix- 
 ture in a crucible, till it ceafes to flame. 
 The Salt is then pulverized and thrown, 
 whilft hot, into twice its quantity or lefs of 
 
 water, and the Lixivium palled through a. 
 filter. 
 
 The properties of this Lixivium, hitherto 
 obferved are thefe. Mixed with a folution 
 of Alum and Vitriol of Iron, it precipitates 
 green and blue Feculae : See page 72. 
 Added to a folution of Gold made in Aqua 
 regis, or of Silver, Quickfilver, or Zinc in 
 Aqua fortis, in fuch proportion as to fatu- 
 ratethe acid, it precipitates the metals like 
 fimple alcalies : But if a larger quantity of 
 the Ley is afterwards added, all the Preci- 
 pitates are rediffolved by it. Mr Margraff 
 relates ( Metnoires de T Acad. de Berlin, 1745) 
 that even when the Precipitates have been 
 carefully edulcorated, or wafhed from their 
 faline matter by hot water, they Hill rea- 
 dily difiolve in the Lixivium ; and this, 
 whether the precipitation has been made 
 with the Lixivium itfelf, or with common 
 alcalies. Lead and Tin refill: this men- 
 ftruum : After they have been thrown down 
 by it from their folutions in acids, they are 
 not taken up again by a larger addition. 
 
 Cauftic alcalies, applied in the fame 
 manner, are not found to difiolve any of 
 the above metals. 
 
Artificial Vegetable Produ&ions, 477 
 
 The greateft quantities of Sope are made in Spain, Portugal, France and S o p n. 
 Italy; Oil Olive being in thofe countries mod plentiful. The mod common 
 and the cheapeft, of the foreign Sopes, is that of Venice. I have feen the pre- 
 paration of this fort: It is made from three parts of good Oil Olive, and two 
 of a cauftic Ley ; which Ley is drawn from two parts ofSpanifh Soda and one 
 of Quick-lime, with a fuitable quantity of water. No metalline veflels are 
 made ufe of : The boilers are compofed of building done, joined by a particu- 
 lar cement, and fecured with iron cramps : In thefe the Oil and Ley, to the 
 quantity of fome hundred weights at a time, are kept gently fimmering for 
 feveral days and nights. The Venetians prepare alfo a green Sope, from old 
 Oil, the Mother-ley of the white Sope, and other refufe matters, adding a cer- 
 tain portion of thejuice of Beet-leaves, which communicates the green colour : 
 
 The juice is preffed out by a horfe-mill confiding of an horizontal done, with a 
 perpendicular one turning upon it, as in the Gunpowder-mills The com- 
 
 mon coarfe Sopes are made with Tallow; and the foft, blackilh and greenilh 
 forts with Train-oil. 
 
 Fixed alcalies unite much more difficultly with effential Oils than with the Sope with ef- 
 exprefled. f or making a Sope with Oil of Turpentine, formerly celebrated as fenhal Oils, 
 a medicine under the names of Sope of Tartar, the Univerfal Corredtor, £sV. 
 
 Different precedes have been purfued, and all of them tedious or defective. 
 
 Some mix the Oil of Turpentine with a well calcined Salt of Tartar, and dir 
 them together every day for half a year or longer, till the union is completed : 
 
 Some dry the mixture occafionally, as often as it is found to have imbibed 
 moidure from the air. Some have fecured the mixture in a drong glal's fixed 
 to the clapper of a mill or the fail of a windmill, that by this means it might be 
 kept in condant agitation; but fimple agitation is not fufficient. Some boll 
 the Oil with a caudic Ley, keeping the whole continually dirring, nearly in the 
 fame manner as for making Sope with exprefftd Oils. Others pulverize the 
 Salt, drongly heated, in a mortar, and pour upon it whild very hot; the Oil 
 of Turpentine likewife heated : By this method a Sope is mod expeditioudy 
 
 obtained, but the more fubtile parts of the Oil are diffipated. The bed way is, 
 to mix the Oil and Salt together moderately hot, and diged them in a low 
 glafs body for a day, then grind and diged them again (m). It is not of much 
 importance to be curious about the proportions: If the Salt predominates, the 
 Oil will the more readily and more perfectly unite with it, and when the union 
 is obtained, the fuperfluous Salt may be feparated by deliquiation : The pro- 
 
 cefs 
 
 ( m) Combination of fixed alcalies with effien- 
 tial Oils.} Stahl has difeovered an eafy me- 
 thod of obtaining this union, by the media- 
 tion of Spirit of Wine— If fome fixt alcaline 
 Salt be put. into a vial, a phlegmatic Spirit 
 of Wine poured upon it, and above this a 
 light diftilled Oil ; the feveral matters, 
 fhaken together, feparate again, and form 
 four diftin£t fubftances, which fome of the 
 fanciful fons of chemiftry have refembled to 
 the four elements feparating from the chaos; 
 the Alcali at the bottom reprefen ts earth ; 
 
 the phlegm of the fpirit, imbibed by a part 
 of the Alcali, represents water ; the fpirit it- 
 felf ftands for air; and the diftilled Oil for 
 fire. Thefe phaenomena having been two 
 or three times exhibited, and the mixture, 
 two days after, being fhaken a third time, 
 no feparation enfued, the Alcali and Oil 
 uniting into a thick, faponaceous mafs, 
 the product here required. To fucceed in 
 this experiment, the quantity of Oil fhould 
 be fmall. 
 
 5 
 
47 8 Artificial Vegetable ProduEllons . 
 
 S o p e s. cels may be finifhed by drawing over feveral times from the Sope fome rectified 
 Spirit of Wine, by which, if there is any redundant Oil, it will be in good 
 meafure feparated. The other effential Oils are ftill more difficultly combin- 
 able with alcalies than that of Turpentine; but empyreumatic Oils unite more 
 eafily. Volatile alcalies do not form a Sope with any kind of Oil : They only 
 thicken exprdfed Oils into the confiftence of a liniment ; and it is only the 
 Spirit of Sal ammoniac made with Quick-lime that does this. 
 
 Common hard Sope dilfolves in water (though not perfectly) by virtue of its 
 alcaline Salt. But it diffolves alfo, and that in a more perfect manner, in rec- 
 tified Spirit of Wine, though this menftruum has no adtion either on the Oil 
 or the Salt by themfelves : It is oblervable, that a fmall proportion of Sope 
 gives a quite thick confiftence to a very confiderable quantity of the fpirit. On 
 adding any acid to a folution of Sope, its ingredients feparate from one ano- 
 ther, the Alcali being abforbed by the acid, and letting go the Oil («). 
 
 Sope is ufed medicinally as a detergent and deobftruent : It diffolves tenacious 
 mucus, and promotes the natural excretions. If there are any medicines capable 
 of diffolving the calculus in the bladder, Sope is one of the principal (o), 
 
 PART 
 
 (n) Solubility of Sope."] This concrete dif- 
 folves Hill more perfectly, and in larger 
 quantity, in pure proof-fpirit. Sixteen 
 ounces of rectified fpirit fcarcely dilTolve one 
 ounce of Sope ; but the fame quantity of a 
 mixture of equal parts of rectified fpirit and 
 water, diffolves with eafe above five ounces 
 into a colourlefs tranfparent liquor. This 
 folution is commonly called liquid Sope — 
 It is obfervable that the Oil, feparated from 
 folutions of Sope by means of acids, dif- 
 folves, like effential Oils, in Spirit of Wine. 
 See page 464. 
 
 (0) Additional Article. 
 
 VEGETABLE EARTH. 
 
 'T' HE earthy parts of vegetables are not 
 to be feparated, in a tolerably pure 
 ftate, but by diffipating or deftroying the 
 other principles. There are two general 
 means of effecting this ; putrefying, and 
 burning the fubjeCt. 
 
 The earths procured by thefe two pro- 
 ceffes, from one and the fame plant, are in 
 all their obvious properties, remarkably dif- 
 ferent from one another ; but in thofe ob- 
 tained by one procefs from different plants, 
 no diverfity has been obferved. All vege- 
 tables feerrt to be refolved by putrefaction 
 into one fimilar earth, and by fire intq ano- 
 ther. 
 
 The earth produced from vegetables by 
 
 putrefaction, of which common black mould 
 is principally compofed, approaches fome- 
 what to the nature of the lefs tenacious 
 kinds of clayie Earths or boles : Like them, 
 it readily imbibes water, extends a little 
 when moiftened, proves in fome fmall de- 
 gree duCtile, and is not aCted upon (in the 
 cold or in a moderate warmth) by acid li- 
 quors : It differs from them in being lefs 
 coherent, and acquiring no additional hard- 
 nefs in the fire. Calcined by a very fixong 
 fire it does not become fimilar, either in ap- 
 pearance or in its chemical properties, to 
 the earth procured by burning the plant at 
 firft---Some have fearched in mould for the 
 immediate pabulum or nutrimental matter 
 of vegetab’es, but the enquiry has hitherto 
 been fruitlefs : The richnefs of mould as a 
 foil for plants, does not feem to depend on 
 its having any particular faline or other im- 
 pregnation, but on its property of imbibing 
 and retaining humidity more effeCtually than 
 any other earth. 
 
 The earth prepared by fire, or the afhes 
 of vegetables freed from their faline parts, 
 diffolves readily and plentifully in all acids, 
 and appears to be fimilar to the mineral earth 
 called Magnefia, or the earthy bafis of the 
 bitter purging Gaits of mineral waters : (See 
 page 190.) It forms the fame compounds 
 with acids ; and like that earth alfo, it 
 acquires no acrimony nor any change of its 
 quality, from fire. By the procefs of putre- 
 faction, 
 
Artificial Vegetable Productions. 
 
 479 
 
 fa£fion, in mixture with putrefcible fub- 
 ftances, it fuffers no change, the incinerated 
 earth being recoverable from that which 
 the putrefadfion produced, by means of 
 acids ; and afterwards from the acids, by 
 precipitation with alcaline Salts and by cal- 
 cination ; and proving (till, on all the trials 
 that have been made, the fame earth as at 
 firft. 
 
 The vitrification of the mineral Mao-- 
 nefia has not been tried. The vegetable 
 incinerated earth, mixed with a very mode- 
 rate proportion of fixed alcaline Salt, vitri- 
 fies with eafe, and forms a greenifh hard 
 Giafs. The common green Glafs-bottles 
 are made chiefly of vegetable afh.es, that 
 have not been freed from the Salt produced 
 in the burning ; the proportion of which is 
 often fufficient for the fufion, not only of 
 the earthy part of the afhes themfelves, but 
 likewife of an additional quantity of Sand or 
 other mineral Earths. The warm imagi- 
 nation of fome of the chemifts has wantoned 
 in airy fpeculations about this green Giafs, 
 imprefled with the indelible character of the 
 verdant kingdom, tinged with an unfubdu- 
 able green anima of plants. 
 
 In fome chemical operations, where re- 
 torts or other vtlfels of green Giafs are ex- 
 pofed for a confiderable time to the action 
 of a ftrong fire in a Sand-bath, the bottom 
 of the Giafs that had been in contadf with 
 the Sand, is often found tinged in part with 
 an opake whitifhnefs. From this obferva- 
 tion I was induced to cement pieces of 
 Giafs in a crucible, with Sand and many 
 other powdery matters : In thefe experi- 
 ments, the Giafs frequently buffered a re- 
 markable change in its whole fubftance, be- 
 ing converted throughout into a body more 
 refembling a fine kind of earthen-ware than 
 Giafs. Mr. Reaumur was led to the fame 
 difeovery by analogical reafoning: From 
 the efFe£fs of Bone-afh, Charcoal, Soot, &c, 
 in foftening caft Iron, and turning forged 
 Iron into Steel, (Seepage 78.) he fufpedt- 
 ed, that the fame fubltances might produce 
 alfo fome notable alterations in Giafs; and 
 accordingly firft made trial of thofe pow- 
 ders, and afterwards of others — The fol- 
 lowing is the general refult of the experi- 
 ments made upon this fubjeCb by him *. 
 An account of our own will follow this to 
 
 the prefs, in a work which I have longVF. getabls 
 promifed to the publick. Earth. 
 
 Green Giafs, furreunded with white 1 — . — -» 
 
 earthy matters, as white Sand, Gypfum or 
 Plafter-of-Paris, &c. and expofed to a con- 
 fiderable heat not ftreng enough to alter 
 its figure, - as that of a potter’s furnace, 
 acquires different fhades of blue, and by de- 
 grees begins to grow white. On breaking 
 the Giafs, the white coat appears to be com- 
 pofed of fine, glofty, fattin-like fibres, run- 
 ning tranfverfely and parallel to one ano- 
 ther ; the Giafs in the middle being*fcarcely 
 altered. On continuing the cementation, 
 the change proceeds further and further, till 
 at length the white fibrous parts from both 
 fides meet in the middle, and no appearance 
 of Giafs remains. By this procefs entire 
 velFels of Giafs are converted into veflels of 
 Porcelane. 
 
 The fubftance, into which the Giafs is 
 thus converted, is opake, compadf, inter- 
 nally of great whitenefs, equal to that of 
 the fineft China-ware, but externally of a 
 much duller hue. It is confiderably harder 
 than Giafs, much Jefs fufible in the fire, 
 and fuftains alternations of heat and cold 
 without injury. Veflels of it, cold, beat- 
 boiling liquors, and may be placed on the 
 fire at once, without danger of their crack- 
 ing. I have put a veflel of this Porcelane, 
 fays the author, into a forge, furrounded it 
 with coals, and kept blowing vehemently 
 for near a quarter of an hour : I have 
 melted Giafs in this veflel, without its 
 having buffered any injury in its figure. 
 
 If means could be found of giving the 
 outfide a whitenefs equal to that of the in- 
 ternal part, Giafs veflels, might thus be 
 converted into a valuable kind of Porce- 
 lane fuperior to all that have hitherto been 
 made. Chemiftry may receive from this 
 difeovery in its prefent ftate, fuch veflels 
 as have long been wanted ; veflels, which 
 with the compadtnefs and impenetrability 
 of Giafs, are free from its inconvenien- 
 cies. 
 
 1 his difeovery has not as yet been 
 brought to the degree of perfection which 
 the author thinks it capable of being brought 
 to. Many other experiments remain to be 
 made, with different kinds of Giafs, as well 
 as with different cementing materials. 
 
 * In the Memoirs of the Royal Academy of Sciences for the year 1739. 
 
 Ths 
 
480 
 
 Vegetable 
 
 Earth. 
 
 Artificial Vegetable Productions. 
 
 The common green glafs bottles yielded 
 a Porcelane of tolerable beauty ; window 
 glafs and drinking glafles a much inferior 
 one ; whilft the finer cryftalline glafles 
 could not be changed into Porcelane at all. 
 Whence it is natural to prefume, that there 
 may be fome forts of Glafs more proper 
 than any that have yet been tried. It may 
 perhaps be found neceflary to prepare a 
 coarfe kind of Glafs on purpofe. 
 
 7 With regard to the cementing materials, 
 he finds white Sand and Gypfum, or rather 
 a mixture of both, to anfwer the belt of 
 any that have been tried. Coloured earths 
 generally m|ke the external furface of a 
 
 lighter or deeper brown colour ; Soot and 
 Charcoal, of a deep black; the internal 
 part being always white. Thefe external 
 colours may be fo managed as to prove in 
 fome cafes an embellilhment. The glaz- 
 ing and vitreous colours, commonly ap- 
 plied upon other Porcelanes, he finds may 
 be equally applied upon this. 
 
 Mr. Reaumur fuppofes (agreeably to the 
 theory by which he was led to the difeo- 
 very), that the converfion of Glafs into Por- 
 celane is owing to the fulphureous or un- 
 vitrefcible particles of the matters with which 
 it is cemented, being forced into it by the 
 heat. 
 
 PART 
 
Wit{ * fic-% * fn* * jHnnj jam* *kk* ^ * j*”M * F'*\ * 
 
 k.k * kjtf * k.Js * k.j^ kj^ **^3*> k.4 kJ* * kjn( * k.ji * k>? 
 
 PART III. 
 
 / 
 
 CHEMICAL HISTORY 
 
 OF THE 
 
 ANIMAL KINGDOM. 
 
 SECTION I. 
 
 Of ANIMAL SUBSTANCES in general , and their 
 
 Native Principles. 
 
 NIMALS are nourifhed, mediately or immediately, by vege- Animals^ 
 
 tables. The alimentary lubftance, of whatever kind, is changed v , - v — 
 
 in the body, by a power of which we know only the effedt, into 
 two kinds of matter; (i.)An excrementitious one, which palTes 
 off through the inteflines ; and (2.) A fluid which is the direcft pa- 
 bulum of the animal ; which is tranfmitted, though not without new changes, 
 through all the veffels ; from which are fecreted and elaborated, by different 
 organs, all the animal juices deftined to different purpofes in the oeconomy, 
 and all the excrementitious fluids ; from which the folid parts alfo receive 
 their nutriment and increafe. 
 
 How widely do thefe fubftances differ from one another, as well as from every 
 thing that pre-exifted in the alimentary fubjedt ! We have no where more 
 ftriking examples of the converfion of matter into new forms, than in the 
 bodies of animals -, changes effected by a natural procefs, which art has at- 
 tempted in vain to imitate or account for. 
 
 Q.q q 
 
 Different 
 
482 Of Animal Substances in general. 
 
 Animals. Different alimentary fubftances are not by this procefs equally changeable: 
 k«— w— — ' They differ obvioufly in regard to the facility of their being digefted or aftimi- 
 lated in the body : Perhaps alfo there are differences in the quality of the ani- 
 mal juices elaborated from different aliments. The common experience of 
 the tables fhews differences in animal flefh, which may in great part be 
 afcribed to the food. 
 
 There are many fubjedts, of the vegetable as well as mineral kingdom, (ex- 
 clufive of the diredtly noxious ones), whofe adtive principles appear to be un- 
 fubduable by the digeftive organs of animals, and which tranfmit their own 
 fpecific qualities to the blood, and to fluids fecreted from ir. Thus Rhubarb 
 communicates its purgative virtue to the milk of the breaft, and its deep yel- 
 low colour to the urine ( a ). 
 
 Animal Animal Substances, chemically examined, are found to contain, be- 
 SuBSTANCEs.j- ic j es ^ g enera [ principles Water and Earth, 
 
 i A gelatinous matter, more or lefs tenacious, foluble in Water, indiffo- 
 luble in redtified Spirit of Wine. This principle appears to be of two kinds •, 
 one which diffolves in boiling water more readily than in cold; and another, 
 which though eaflly foluble in the cold, is by boiling water coagulated and 
 rendered indiffoluble. The gelatinous matter of the folid parts is of the firft 
 kind j that of fome (perhaps of all) of the fluids, of the laft. 
 
 2. A fubftance diffoluble in Spirit of Wine, and which remains behind upon 
 evaporating the fpirit, containing oftentimes the tafte, particular flavour, 
 medicinal adtivity, or colour, of fuch fubjedts as are eminently poffeffed of thofe 
 qualities, as Cantharides, Caftor, Cochineal, &V. 
 
 3. An undtuouS or fat matter, of different degrees of confiftency, eaflly 
 liquefiable by heat, not diffoluble in water or in fpirit, but for the mod part 
 mifcible with cauftic alcaline Lixivia intoSope. 
 
 4. A volatile principle, which exhales in the heat of boiling water, and 
 which may fometimes be colledted by diftillation in the form of an effential 
 Oil {b). 
 
 <5. An acid ; which feems to be more frequent in the animal kingdom than 
 thechemifts have commonly imagined ; for beffdes the manifeft acid of cer- 
 tain infedfs, experiment has difcovered that there is a latent acid principle in 
 snoft kinds of animal fubftances. 
 
 THESE 
 
 (a) Qualities of vegetables unfuldued in ani- 
 mal bodies.] Many other examples of this 
 kind might be mentioned ; among which 
 perhaps there is none more remarkable than 
 the experiments formerly related (p. 387.) 
 of the bones of animals being ftained of a 
 deep red by a red drug (Madder) taken 
 with the food. 
 
 (. b ) Effential Oil.] Our author appears to 
 be the firft who difcovered any truly effen- 
 tial Oil in the animal kingdom ; fee the exa- 
 mination of ants In the following fedtion. It 
 
 is faid that fome of the ftrong-fcented animal 
 fubftances alfo, as Caftor, yield on being di- 
 ftilled with water, when large quantities are 
 fubmitted to the operation at once, a fmall 
 portion of adtual Oil containing the whole 
 fmell of the lubjedh From hence fome 
 have prefumed, that animal odours in gene- 
 ral refide, like thofe of vegetables, in a prin- 
 ciple of this kind, though the proportion of 
 Oil, in animal as well as in many odorife- 
 rous vegetable fubftances, is too fmall to be 
 collected on diftilling moderate quantities 
 of the fubjedt. 
 
Of An imal Substances in general. 48 3 
 
 THESE may be looked upon as the native principles of animal matters ; Animal 
 all the confident parts of animals being refoluble into more or fewer of thefe. Substances.' 
 without deftroying the original qualities of thefubjedl; which qualities are 
 ufually preferved in one or other of the parts feparated. There are however 
 fome particular animal juices, whofe principles cannot eafily be referred to any 
 of thefe. 
 
 The foregoing principles are in fome degree analogous to the Gums or Mu- 
 cilages, the Refins, the expreflible and efiential Oils, and the effential Salts, 
 of the vegetable kingdom. But notwithftanding the agreement of the reipec- 
 tive principles of the two kingdoms in fome of their general properties, their 
 internal conftitution appears to be eflentially diftind. How different is an ani- 
 mal gelly, thrown in the fire, from a vegetable Gum, in its inflammability 
 and in its ftench ! 
 
 The foft and fluid parts of animals (c) are in general much more difpofed to 
 putrefy than thofe of vegetables ; and when putrefied, prove more acrimonious 
 and more offenfive : Compare a rotten apple with cadaverous flefli, and how 
 different will putrefadion appear to be in the two kingdoms! Vegetables by 
 putrefadion approach in fome meafure to the nature of animal fubflances in 
 their perfed date ; not indeed in. regard to their native principles, but in re- 
 gard to thofe into which they are ultimately refoluble by the dedrudive adion 
 of a drong fire. 
 
 A degree of putrefadion oftentimes takes place in the bodies even of living 
 animals: Thus, after long abdinence from food and liquors, the juices are 
 found to be thin, faline, acrimonious, and fetid. From fuch a date of the 
 juices, brought on by various caufes, arile many diforders of the animal machine, 
 which have in vain been attempted to be counteraded or explained upon me- 
 chanical principles ( d ). 
 
 Many 
 
 (<:) Soft parts difpofed to putrefy .] The folid 
 parts alfo, and even thofe which have very 
 little of the animal principles befides the 
 earth, are found, when reduced into fmall 
 parts and kept moift, to be greatly difpofed 
 to run into putrefadion. I have feen the 
 common abforbent powders, as Crabs-eyes 
 and Crabs-claws, when levigated with water 
 and fet by moift, in large quantities toge- 
 ther and in hot weather, become in fome 
 degree putrid in a few hours. 
 
 (d) Animal putrefaction .] The dodrine of 
 putrefadion, both in living and in dead ani- 
 mals, has lately received great light from 
 the curious experiments and obfervations of 
 Dr. Pringle, many of which are interefting 
 to the chemift as well as the phyfician. See 
 the appendix to his Obfervations on the Dif- 
 eafes of the Army . 
 
 He obferves, that during putrefadion, a 
 quantity of air is generated, all the humours 
 become gradually thinner, and the fibrous 
 parts more lax and tender ; that the crafla- 
 mentum of human blood changes by putre- 
 fadion to a dark livid-coloured liquor, 
 which tinges a large quantity of ferum of a 
 tawny hue like Ichor, CSV. and recent urine 
 of a flame colour, like that in fevers and the 
 feurvy ; that this laft mixture, on Handing 
 an hour or two, gathers a cloud like that of 
 the crude water of acute diftempers, with 
 fome oily matter on the furface like the 
 feum on fcorbutic urine ; that the ferum of 
 blood depofites, in putrefadion, a fediment 
 refembling well digefted pus, and changes 
 to a faint olive-green 5 and that the green 
 colour of falted meats is owing to this caufe, 
 and not, as is commonly luppofed, to the 
 brine. 
 
 Q.q ft 2 
 
 He 
 
4 8 4 
 
 Animal 
 
 Substances. 
 
 V m il l — 1 ^ III 1 
 
 Of An i m a l Substances in general. 
 
 Many animal juices are difpofed likewife to coagulate and grow thick, and 
 to change in part into hard concretions, without any manifeft evaporation of 
 the fluid. By this property they are fitted tor augmenting, and repairing the 
 waftes of the folids. Thus the thells of fundry fifhes receive annually a new 
 incruflation ; and thofe of others are annually thrown off and fupplied by new 
 ones produced from the juices of the animal. 
 
 It has been fuppofed, that the teftaceous, calculous, and other folid animal 
 concretions, are only a bare feparation and coalefcence of the earthy particles 
 previoufly diffolved or held fufpended by the fluids ; but a chemical examina- 
 tion thews that they are more. Evaporate the watery part of any animal juice, 
 and by a fuitable fire burn off the combuftible principles, that only the earth 
 may remain : Procure alfo, by the like means, the pure earth of any of the 
 hard parts of animals j and the two earths will be found effentially different 
 from one another ( e ). 
 
 He finds that putrefaction is prevented or 
 retarded by all faline fubftances, even by 
 fixed and volatile alcaline Salts, which have 
 been commonly fuppofed to produce a con- 
 trary efFedt, by vinous fpirits, aromatics, 
 many gummy-refins, the bitter, aftringent, 
 acrid herbs, dsY. . .That Sea-falt, the com- 
 mon feafoning of our provifions, is one of 
 the weakeft in antifeptic power; that vi- 
 triolated Tartar for inftance is twice as 
 ftrong ; Sal ammoniac thrice, Nitre up- 
 wards of four times, fixed and volatile al- 
 ealies as much, Borax above twelve times. 
 
 Salt of Amber above twenty times, Alum 
 above thirty times, and the foluble part of 
 Camomile-flowers not lefs than one hun- 
 dred and twenty times, as flrongly antifep- 
 tic as common Salt . . . That animal fub- 
 ftances already corrupted are capable of be- 
 ing recovered and made fweet again : A 
 ftnall piece of putrid flefh, fteeped two or 
 three days in an infufion of Camomile re- 
 newed every day, loft its oftenfivenefs ; and 
 being then put into a frefti infufion,. was 
 kept a twelvemonth in the fame liquor, and 
 ftill remained firm and uncorrupted . . That 
 Sea-falt in fmall quantity, as ten grains to 
 two drams of flefh and two ounces of wa- 
 ter, inftead of refilling, both haftens and 
 heightens the putrefadlion . . And that fome 
 
 of the foluble earths alfo, as Chalk, promote 
 putrefaction ; whilft others, as egglhells, 
 i'eemed to retard it. 
 
 It is remarkable, that notwithftanding 
 the ftxong tendency of animal matters to 
 putrefadtion, yet broths made from them 
 with the admixture of vegetables, inftead of 
 putrefying, turn four. Dr. Pringle finds 
 that animal flefh in fubftance being beat up 
 with bread or other farinaceous vegetables, 
 and a proper quantity of water into the 
 confiftence of a pap, this mixture likewife, 
 kept in a heat equal to that of the human 
 body, grows in a little time four, whilft the 
 vegetable matters without the flefh fuffered 
 no fuch change. He obferved that in a 
 fmaller degree of heat, the change was 
 more flow, and that the matter before it 
 became acid yielded a vinous fmell like that 
 of fermenting liquors. 
 
 (e) Earths from the foft and hard parts diffe- 
 rent.^ The principal difference I have ob- 
 ferved is this ; that the earths of the foft 
 parts of animals, at leaft of thofe which 
 were examined, diffolved with eafe in the 
 vitriolic acid, whilft thofe of the hard parts 
 did not diffolve at all, any more than the 
 mineral calcareous earths. See the article 
 of animal earths at the end of next fedtion. 
 
 SECT. 
 
[ *8 5 1 
 
 SECT. II. 
 
 Products from Animal Subjlances by Fire . 
 
 A NIMAL Subftances (a few excepted) on being diftilled in clofe vef- 
 fels by a ftrong fire, give over, not a manifefi: acid liquor as vege- 
 tables do, but an urinous or volatile alcaline one, and commonly more 
 or lefs of a concrete volatile alcaline Salt; together with an empyreumatic Oil, 
 more fetid than the Oils of vegetables, and ot a different kind of fetor. On 
 calcining the remaining coal in open veffels, and elixating the afhes with water, 
 we fometimes obtain a portion of a kind of fixed faline matter, but very rarely 
 a perfeCt alcali like that extracted from the afhes of vegetables (/). 
 
 Before we proceed to examine Animals and their parts in particular, it will 
 be proper to give an account of the preparation and properties of the general 
 products obtained by this operation. 
 
 Animal 
 
 Substances. 
 
 I. Volatile Animal Salts and Spirits. 
 
 W E have formerly feen that the alcaline Salt procurable from vegetables Volatile 
 is wholly a child of art. The volatile alcalies obtained from animals Salts 
 are in like manner artificial productions, never found toexift naturally in any ■_ > 
 
 animal fubftance in its perfeCt flate : They are generated by the aCtion of fire, 
 and by putrefaction ; and not by any known power befides. 
 
 So foon as an animal fubftance begins to putrefy, it begins to difcover an 
 alcaline quality ; and this volatile fubftance, now produced in it, may be fepa- 
 rated by diftillation in a very gentle warmth (g). Hence in the bodies of ani- 
 mals 
 
 (f) Salt from the ajhes .] The afhes of 
 truly animal fubftances, are never obferved 
 to yield any perfeCt alcaline Salt like that 
 produced from vegetables. Wherever we 
 obtain a fixed Alcali of this kind, the fub- 
 je£t is judged, in fo far as it affords that 
 Salt, to be of a vegetable nature or to par- 
 ticipate of a vegetable impregnation. 
 
 The fmall portion of faline matter, ex- 
 tracted from the afhes of fome animal fub- 
 ftances, appears to be chiefly of the marine 
 kind. Our author himfelf finds, in exa- 
 mining bones and horns, that a Salt of this 
 kind is obtainable from them in their crude 
 ftate, by boiling them with water. If the 
 acid of this Salt fhould be diffipated in the 
 burning, fo as to leave the. Alcali behind ; 
 
 this Alcali may be eafily diftinguifhed from 
 thofe of the vegetable kingdom by its form- 
 ing with the vitriolic acid a bitter neutral 
 Salt, eafily foluble in water and fufible in 
 the fire, called Sal mirabile, (See page 193.) 
 whilft the vegetable Alcali forms with the 
 fame acid a Salt lefs bitter, very difficult of 
 folution, and not at all fufible, called vitrio- 
 lated Tartar. (See page 190). 
 
 (g) Putrid fubjlances alcaline ---yield their Al- 
 cali in gentle warmth .] This is the general 
 doCfrine of the chemifts, but it does not ap- 
 pear to be ftri&Iy juft. They feem to have 
 been milled by applying to all animal fub- 
 ftances what they had found to obtain in 
 one, but what a further examination fhews 
 
 too 
 
486 VroduEls from Animal Subfances by "Fire. 
 
 Volatile mals themfelves, thejuices arefomedmes found to be alcalefcent; more or lefs 
 Salts, fo, in proportion to the degree to which the putrefaction has arifen. 
 
 ^ — -v - — > From thofe fubftances on the other hand, which have not buffered putrefac- 
 
 tion, no Alcali is obtainable without a ftrong heat ; the formatiqn of the 
 Alcali, when effected by fire alone, not taking place till the fubjeft is in a ftate 
 / of ignition. The Alcali itfelf, when once produced, whether by fire or by 
 putrefaction, is always of the fame volatility. 
 
 Di/Ullation. I N order to the preparation of volatile Saits, the folid parts of animals, 
 which are little difpofed to putrefy, as Horns, Bones, Hoots, Hair, &c. are 
 diftilledin earthen or coated glafs retorts placed in a reverberatory orotherfur- 
 nace, capable of giving a confiderably ftrong heat : In the large way of bufi- 
 nefs, an iron pot is ufed for the diftilling veffel. The fire being increafed by 
 degrees, there arifes firft a phlegmatic liquor, in greater or lefs quantity ac- 
 cording as the fubjeCt was lefs or more dry : In the progrefs of the operation, 
 the liquor that diftils proves more and more alcaline and urinous, and is now 
 called Spirit : Soon after, a concrete Salt appears in the recipient, together 
 with a yellow Oil which is fucceeded, on increafing the fire to the utmoft, 
 by a dark coloured thick Oil. 
 
 Liquid fubftances, as Urine and Blood, are previoufiy putrified, and then 
 diftilled in a fand-bath. In regard to the putrefaction, the fubjeCt fhould be 
 completely putrid, but the procefs muft not be carried too great a length ; for 
 if it is, the volatile Salt will be difiipated in the air, and nothing will arile in 
 the diftillation but a little fetid Oil. The diftilling veffel fhould not be above 
 one half filled, thefe kinds of liquids being extremely apt to froth up and run 
 over: Nor fhould the junctures be very clofely luted, left the expanfive va- 
 pours which arife from thefe fubjeCts fuddenly and in great abundance, burft 
 the veffels or blow off the head or receiver. This laft caution is equally ne- 
 ceffary to be obferved in the foregoing diftillation of folid fubftances by a re- 
 verberatory or naked fire. 
 
 The liquor which in thefe proceffes is called Spirit, is no other than a por- 
 tion of the volatile Salt diffolved in the water or phlegm, and tainted with the 
 fetid Oil. The Salt itfelf alfo, which concretes in a folid form about the fides 
 and in the upper part of the recipient, is ftrongly impregnated with the fame 
 fetid fmell, and with the unfightly yellow or brownifh colour of the Oil. 
 
 Reification. I N order to feparate and purify the feveral produCls, the Salt may be walked 
 down by fhaking about the liquid matters in the receiver, and the whole 
 poured into a wide- mouthed glafs: On Handing, the Salt falls to the bottom, 
 the Spirit fwimming above it, and the Oil on the top. The liquor may then 
 
 be 
 
 to obtain in very few, if any, befides, at 
 Jeaft in any confiderable degree. 
 
 Putrefied urine gives plain marks that it 
 contains a volatile Alcali already generated: 
 But putrid blood and flefh are not fenfibly 
 alcaline, and yield no Alcali in diftillation 
 till after the phlegm has arifen. 
 
 We have formerly feen that volatile alca- 
 
 Jies are powerfully antifeptic. Perhaps, as 
 Dr. Pringle obferves, it is owing to this 
 Alcali in putrefied urine, that its fteams are 
 fo little prejudicial to health ; whilft thofe 
 of other putrid animal matters, which want 
 that corrector of putrefaCtion, are often 
 productive of dangerous difeafes. 
 
ProduSls from Animal Suhfiances hy Fire . 
 
 be poured off from the Salt, and the Oil and Spirit parted from one another by Volatile 
 a funnel or otherwife (h). Salts. 
 
 After this grofs feparation, the fpirit is to be diftilled over again, in a glafs v — -v— 
 retort, with a very gentle heat; and the fire difcontinued, or the receiver 
 changed, as foon as its fetid Oil is perceived to arife. By repetitions of this 
 procefs, it iofes its offenfive fmell, though it cannot be totally diverted of 
 its Oil. 
 
 The Salt is rectified or purified by repeated fublimations ; with the addition 
 of animal or vegetable afhes, fine white Clay, or other like earthy powders, 
 which abforb and keep down a portion of the Oil. Great part of the Oil may 
 be feparated alfo by digeftion with highly rectified Spirit of Wine; this men- 
 ftruum diftolving and extracting the Oil, without being able to dirtolve any 
 confiderable quantity of the Salt : The little of the Salt which it does take up, 
 may be feparated by diftillation in a tall glafs with a gentle heat ; the Salt ariles 
 firft, and afterwards the Spirit, greateftpart of the Oil remaining behind. 
 
 The Salt contained in the volatile Spirit may in like manner be recovered in 
 its folid form by gentle diftillation. For this purpofe, the procefs is to be 
 ftopt as foon as the Salt has arifen, before any phlegm comes over to diffolve 
 it; whereas, in rectifying it for Spirit, the diftillation is continued till phlegm 
 enough has arifen to diffolve the whole of the Salt (i). 
 
 Volatile Salts can fcarcely by the above methods of rectification be rendered 
 perfectly pure. Though when newly rectified, they appear fufficiently white, 
 and difcover only their own pungent odour, yet in long keeping they contract 
 a brown colour and an ill fmell, and thus betray how imperteCtly they had 
 been freed from the Oil. 
 
 The molt effectual method of purifying them, though tooexpenfive an one 
 for common purpofes, is, to combine them with mineral acid fpirits, that of 
 
 Sea-falt for inftance When volatile alcalies are faturated with the acid, they 
 
 form a neutral Salt of a middle degree of volatility ; if the filtered liquor be 
 fet to evaporate, the water totally exhales long before the Salt begins to arife. 
 
 Some of the chemifts, anxious when they had Salts that were fixed, to make 
 them volatile, and when they had volatile ones to make them fixed, imagined 
 
 they 
 
 (h) Spirit and Oil parted.] The Spirit may 
 be commodioufly feparated from the Oil by 
 filtration through wet paper, which will re- 
 tain all the Oil that is not intimately com- 
 bined or diffolved in it. 
 
 (i) Phlegm enough to diffolve the Salt.] The 
 diftillation ftiould be ftopt as foon as ever 
 the Salt appears to be all diflblved ; for the 
 phlegm drawn off after this period can ferve 
 only to weaken and dilute the Spirit in pro- 
 portion to its quantity. The author of the 
 Pharmacopoeia refer mata advifes the operation 1 
 to be difcontinued a little before the total 
 diffolution of the Salt, and it were to be 
 wiftied that this method was received in 
 praffice. The ftrength of volatile fpirits,., 
 
 at prefent very vague and uncertain and not 
 eafily to be judged of, would then be al- 
 ways nearly of one ftandard ; for if a little 
 of the Salt remains undiffolved at the bot- 
 tom of the liquor, we may be fure that the 
 fpirit is faturated, or impregnated with as 
 much as it can take up. This method 
 would likewife prevent the frauds that have 
 been praCtifed in regard to thefe kinds of 
 preparations ; for a little folid Salt remain- 
 ing at the bottom (provided this Salt be 
 found to be a volatile alcaline one, which is 
 very eafily determined) would be a certain 
 mark that the fpirit is not only ftrong, but 
 free from the fophiftications mentioned ini 
 page 490. 
 
488 Produ&s from Animal Subfiances by Fire. 
 
 VoLATiLEthey had here a curious fixation of the volatile Alcali, and expected from it 
 Salts, uncommon effedts, not confidering, that the compound is by no means an ai- 
 , — u caline, but a neutral Salt, and no other than plain Sal ammoniac ; for com- 
 mon Sal ammoniac is an artificial neutral Salt, compofed of volatile Alcali 
 and marine acid. (See pag. 21 6,feqq.) If this compound be mixed with 
 fixed Alcali or with Chalk, and fet to fublime in a retort or other proper vef- 
 fel, the acid will be abforbed by the fixed Salt or the Earth, and the volatile 
 Salt will arife pure. 
 
 Theiridentity THE volatile Salts and Spirits, obtained from different animal fubftances, 
 and diflimila-have been fuppofedto poffefs ipecific medicinal virtues, correfponding to thofe 
 nt y- of the fubjed they were produced from. But fire and putrefadion, the agents 
 
 by which thefe produds are procured, deftroy the fpecific qualities of all ani- 
 mals and vegetables ; and the volatile matters, that arife in the diftillation, 
 have no more refemblance to the original fubjeCt than the coal that remains be- 
 hind. The Salt and Spirit of Cantharides have no greater acrimony than thofe 
 of Hartfhorn-gelly : Thofe of the mod poifonous and loathfome animals, the 
 Tarantula, the Scorpion, the Afp, the Spider, and the Toad, are neither lefs 
 innocent nor more offenfive, than thofe of the Partridge, the Lark, and the 
 Ortolan. 
 
 Though thefe preparations, however, poffefs nothing of the properties of the 
 fubjed which afforded them, it does not follow, that in their ordinary ftate 
 they are all perfedly the fame, as fome have too haftily concluded. When 
 brought to their ultimate degree of purity, their identity is not to be denied : 
 But fo long as they participate of Oil, which they always do as prepared in the 
 common manner for medicinal or other ufes, thofe Oils may vary their quality ; 
 for though pure animal Salts appear all to be one and the fame, yet animal 
 Oils are not fo. The Salts of different animal fubftances exhibit, by virtue of 
 their diflimilar Oils, very different phenomena in the precipitation of certain 
 metallic folutions, as thofe of venereal Vitriol and corrofive Sublimate. 
 
 The pure volatile Salt or Spirit of Sal ammoniac may be rendered perfedly 
 fimilar to thofe of any particular animal matter, by adding a fmall portion of 
 the Oil of the fubjed whofe Salt or Spirit is to be imitated, and combining 
 them together by digeftion, fublimation, or diftillation. 
 
 Their eneral WITH regard to the properties of volatile Salts, they pofiefs the general 
 properties, charaders of alcalefcence in common with the fixed alcalies, as changing Syrup 
 of Violets green, effervefcing with adds, and precipitating fubftances diffolved 
 in them (k). 
 
 They 
 
 (/■) Volatile alcalies precipitate fubjlances difi- when only a certain quantity of the Al- 
 Johed in acids like the fixed .] This rule is cali has been added, equally as by the 
 much lefs general, and the effeds of vola- fixed ; yet on adding a larger quantity of the 
 tile and fixed alcalies are in thefe refpeds, volatile Alcali, great part of the precipitated 
 at leaf! in regard to metallic folutions, more Gold is taken up again, whilft the fixed, 
 different from one another, than has been in whatever quantity it is employed, redif- 
 commonly fuppofed. folvesnone: The Precipitate made by vo- 
 
 Thus though Gold, diffolved in Aqua latile alcalies fulminates with violence on be- 
 regis, is precipitated by volatile alcalies, ing expofed to a fmall degree of heat, whilft 
 
 5 that 
 
ProduEts from Animal Siibftaitces by Fire. 489 
 
 They form with the acid a neutral Salt, which readily concretes upon duly Volatile 
 evaporating the liquor, into a cryftalline form, and which requires a confider- Salts. 
 able heat to make it fublime, whilft the volatile alcalies by themfelves exhale i — 
 even on the warm hand. Thefe neutral compounds are called by the general 
 name of Ammoniacal Salts ; common Sal ammoniac being the principal of them, 
 or that which has been themoft generally known. Of the ammoniacal Saks 
 compofed of volatile alcalies and the different mineral acids, an account has 
 already been given in the firft part of this work, pag. 194. 197, 216. 
 
 Volatile alcalies have lefs affinity or attraflion to adds than fixed, alcalies 
 have; fixed alcalies abforbing the acid from them, on which the volatile Al- 
 cali, now fet at liberty, arifes with a gentle warmth and on this principle de- 
 pends the common method of extrafting the volatile Alcali from ammoniacal 
 Salts. 
 
 Chalk 
 
 that made by the fixed (unlefs there was 
 previoufly a volatile one in the menftruum, 
 as is the cafe when the Aqua regis is pre- 
 pared with Sal ammoniac), bears to be ig- 
 nited, and melted into Gold again, without 
 the leafl: explofion. 
 
 In like manner, Silver and Bifmuth dif- 
 folved in Aqua fortis, and Copper in all 
 acids, are totally and permanently precipi- 
 tated by fixed alcalies ; but either not pre- 
 cipitated at all, or readily diflolved again by 
 the volatile. Solution of Platina in Aqua 
 regis is not precipitated totally, and folution 
 of Zinc in Aqua fortis is fcarcely precipi- 
 tated at all, by either Alcali. 
 
 expofed to the air . . That Silver does not 
 feparate from the liquor on fuch expofure, 
 but that upon the exhalation of the fuper- 
 fluous moifture, it fhoots into fine cryfials, 
 which diflolve, by the afliftance of heat, in 
 rectified Spirit of Wine; from which they 
 again concrete in the cold, into elegant cry- 
 ftallizations . . . That Sea-falt or its acid 
 throws down Silver from its volatile alcaline 
 folution, in form of a white Precipitate, but 
 that the vitriolic acid produces no change . . 
 That Mercury, added to this folution, unites 
 with the Silver, and forms with it in a fhort 
 fpace of time, the efflorefcences called Arbor 
 Dianes. 
 
 Mr. Marggraf has given fome curious 
 experiments on this fubjeck, in the Memoirs 
 of the Academy of Sciences of Berlin for the 
 year 1745. He finds that volatile fpirits 
 (it was the common Spirit of Sal ammoniac 
 he made ufe of) not only rediflolve fundry 
 metallic bodies after having precipitated 
 them, but diffolve even the calces thrown 
 down by fixed alcalies, after they have been 
 feparated from the liquor, and freed as much 
 as poffible from their faline matter by ablu- 
 tion with hot water. 
 
 The calces of Gold, Silver, and Bifmuth, 
 he fays, diflolved with eafe : Thofe of Tin, 
 Lead and Quicknlver feemed to refill; thefe 
 menftrua ; the volatile fpirit having no 
 effedt when added in over-proportion to the 
 liquor after precipitation, any more than 
 when digefted on the edulcorated Precipi- 
 tates. 
 
 He obferves, that the folution of Gold in 
 volatile fpirits depofites the Gold on being 
 
 R 
 
 We have formerly feen (page 476.) that 
 fixed alcalies impregnated by calcination 
 with the inflammable principle of animal 
 fubftances, diflolve thofe metals nearlv in 
 the fame manner as the volatile ; and per- 
 haps it is on the fame principle that the dif- 
 folving power of both alcalies in good mea- 
 fure depends, for volatile alcalies, however 
 purified, are always found to participate of 
 inflammable matter. . Gold and Silver feem 
 to be adted on almofl: equally by both kinds 
 of Alcali : Zinc diflolves mod readily in the 
 fixed, and Bifmuth in the volatile : Quick- 
 filver, though it refills the volatile, diflolves 
 in the fixed, whilft Lead and Tin feem to 
 refill; both. There are fome remarkable 
 differences in the folutions made by the two 
 kinds of Alcali : Thus the marine acid, 
 which precipitates Silver from the volatile, 
 occafions no change in the folution of that 
 metal made in the fixed Alcali. 
 
 r r 
 
49 g ProduBs from Animal Subjlances by Fire. 
 
 Volatile Chalk and other calcareous earths likewife abforb the acid from them when 
 Salts, the mixture is expofed to a confiderable heat, the acid feeming to have a 
 Wronger attraction to the earth than to the volatile Alcali already combined 
 with it. On varying the manner of application, the affinity feerns to be juft 
 the reverfe : Diffolve the Chalk firft in any acid, and the addition of a volatile 
 Alcali will precipitate it ; as if the acid had the greateft affinity to one by dry 
 mixture in the fire, and to the other in the way of humid folution. The re- 
 markable habitude of thefe Salts to Quick-lime has been examined in another 
 place. (See page 222.). 
 
 Volatile Salts diffolve in about four times their quantity of water, and make 
 the liquor fenfibly colder ; whereas fixed alcalies render it fomewhat warmer. 
 On diftilling the folution, the Salt condenfes about the fides of the recipient in 
 a cryftalline form, ufually arranged into different ramifications, which fome of 
 the chemifts have fancifully refembled to the original horns of the Hart from 
 which thefe kinds of Salts have been principally prepared. 
 
 Rectified Spirit of Wine has very little aCtion on thefe Salts. If this Spirit be 
 added to a faturated folution of volatile Salt made in water, it weakens the dif- 
 folving power of that menftruum, and a proportionable quantity of the Salt 
 precipitates (/). Oils and Balfams unite with volatile alcalies by agitation into 
 a femifaponaceous liquid; efienrial Oils eafily, the expreffed difficultly. 
 
 Volatile fpirits, or folutions of volatile Salts in water, diffolve fome metallic 
 bodies, particularly Copper. Added to a folution of this metal made in acids, 
 they precipitate a part, but foon take it up again, and render the liquor of a 
 beautiful fapphire-blue colour. Added to a folution of Mercury-fublimate, 
 they throw down the Mercury in form of a white powder. This laft property 
 
 is 
 
 (/) Volatile alcalies precipitated from water ly 
 Spirit of Wine. ] This property affords a 
 commodions method of diftinguiftiing an 
 abufe, which has been often praftifed in 
 trade, in regard to volatile fpirits ; namely, 
 that of diluting them with a large quantity 
 of water, and fupplying the pungency, thus 
 weakened, by the addition of a little of the 
 penetrating cauftic fpirit made from Sal am- 
 moniac or Urine with Quick-lime. 
 
 On mixing re&ified Spirit of Wine with 
 a genuine volatile fpirit faturated with Salt, 
 a part of the Salt inftantly feparates in form 
 of fmall cryftalline concretions; whereas 
 the fophifticated fpirits, containing little or 
 no actual Salt, can exhibit no fuch appear- 
 ance. 
 
 Some have praAifed an impofition, which 
 though of a groffer kind, eludes this method 
 of trial. A folution of crude Sal ammoniac 
 being mixed with a folution of Pot-afh, the 
 Pot-afh abforbs the acid of the Sal ammo- 
 niac, and fets its volatile Alcali at liberty ; 
 and thus the liquor (efpecially if acuated 
 with a little of the fpirit made with Quick- 
 
 lime) acquires the fame pungent fmell with 
 that of the pure diftilled volatile fpirits. 
 
 As this liquor contains a quantity of re- 
 generated Sea-falt (compofed of the Pot-afh 
 and the marine acid of the Sal ammoniac) 
 and as this Salt is not diffoluble in Spirit of 
 Wine ; it is plain that the counterfeit, on 
 being mixed with that fpirit, will iuffer the 
 fame precipitation that the genuine volatile 
 fpirits do. 
 
 This abufe may be difcovered by evapo- 
 ration, the genuine totally exhaling, whilft 
 the counterfeit leave a fixed Salt behind ; or 
 more readily, by adding to a little of the fu- 
 fpeAed fpirit, a drop or two of a folution of 
 Silver made in Aquafortis. This folution, 
 as I have found on trial, mingles uniformly 
 with pure volatile fpirits, without producing 
 the leaft precipitation or turbidnefs, or un- 
 tranfparency ; whereas, if the fpirit contains 
 the fmalleft portion of Sal ammoniac, or 
 Sea-falt, or regenerated Sea-falt, the two li- 
 quors grow white and milky the inftant they 
 are mixed. The foundation of this expe- 
 riment is obvious from the foregoing note. 
 
\ 
 
 ProduBs from Animal Subfiances by Fire. 491 
 
 3s one of the common criteria for diftinguifhing a volatile Alcali in liquors from Volatile 
 a fixt; the latter throwing down from the folution of Sublimate, not a white, Salts. 
 but an orange-yellow or reddifh Precipitate. ? 
 
 Volatile fpirits are lefs adive menftrua for fundry vegetable and animal fub- 
 ftances, and for Sulphur in the mineral kingdom, than fixe alcaline Lixivia. 
 
 This may be aferibed in great part to their volatility ; which renders them in- 
 capable of bearing the boiling heat that is in many cafes necefifary for enabling 
 fixt alcalies to ad eifedually. 
 
 Volatile Salts, mixed with Nitre and injeded into a red-hot crucible, defla- 
 grate and are deft royed. This experiment, which fucceeds with the pure vo- 
 latile Alcali of Sal ammoniac, as well as with thole which have a manifeft im- 
 pregnation of Oil, evinces that thefe Salts contain an adual inflammable mat- 
 ter as one of their eflfential principles 5 and agreeably to this, it may be obferved, 
 that no volatile Alcali is producible but from fubftances that participate of 
 phlogifton. They apparently contain alfo an earth ; but what other principle 
 or principles enter their compofition, experiment has not hitherto determined. 
 
 II. LATENT ANIMAL ACID. 
 
 # ‘T n H IS acid, which has efcaped the enquiries of many of the chemifts, and Acid. 
 
 whofe exiftence has even been denied, Mr. Homberg has fhewn two v_— y— j 
 ways of procuring. 
 
 One way is, by concentrating the phlegm which arifes firft in the common 
 diftillation of animal fubftances for their volatile Salt and Oil. This phleg- 
 matic liquor being colleded by itfelf, and rediftilled with a gentle heat till only 
 a fmall portion remains, he finds the acid in this refiduum ; which acid he has 
 fometimes concentrated fo far, that it feemed as ftrong as common Vinegar. 
 
 If the quantity of phlegm obtained in the firft diftillation is fmall, it gives when 
 concentrated only flight marks of acidity; where the quantity is greater, the 
 acidity alfo is ftronger, though in either cafe it is fufficiently fenfible. 
 
 The other method of collecting this latent acid is, by mixing earthy mat- 
 ters with the animal fubjeeft at firft, and urging the diftillation after all the 
 alcaline Salt and Oil have arifen. In this cafe, the acid does not come over 
 with the phlegm, but in the liquor forced out at laft by the greateft vehemence 
 of fire. 
 
 The nature and properties of this animal acid we do not know ; nor is is 
 certain that the acids obtained by the two precedes above-mentioned are en- 
 tirely the fame. Perhaps this acid may be no other than a part of the vegetable 
 acid of the food, which has efcaped the digeftive powers of the animal ; for it 
 is difeovered mod remarkably in the blood, bones, &?r. of thofe animals who 
 feed immediately on vegetables (m). 
 
 III. A N I- 
 
 (m) Latent add.] Mr. Pott informs us (in 
 the MiJ'cellanea Berolinenfia , tom . vi. Ann. 
 1740.) that the faline empyreumatic fpirit, 
 which comes over laft in the common di- 
 ftillation of animal fubftances by an intenfe 
 
 R 
 
 fire, leaves, on being rectified, an ammonia- 
 cal liquor, and that the liquor which arifes 
 in the rectification is alfo ammoniacal : For 
 on the addition of a fixt Alcali, it diffufes a 
 ftrong urinous fmelf,* which was difeover- 
 r 2 able 
 
Products from* Animal Subflances by Fire , 
 
 HI. ANIMAL OILS. 
 
 h T s H E Oils which arife in the diftillation of animal fubftances have a ftrong 
 peculiar ftench. Diftil led a fecond time in glafs retorts, by a gradual fire, 
 they leave behind a thick, black, pitchy matter, and thus become more fluid 
 and lefs fetid. By repeated diftillations, either by themfelves or with the addi- 
 tion of Quick-lime or other earthy powders to detain more effectually the grofs 
 fubftance, their quantity is more and more diminifhed, and their empyreu- 
 matic fmell more and more deftroyed ; they become thin, colourlefs, of a fweet 
 tafte, and a grateful penetrating odour. 
 
 It is obfervable that thefeOils diflolve in Spirit of Wine, both when fubti- 
 lized by thefe operations, and in their grofs fetid ftate, though the animal fub- 
 jedt that affords in diftillation a large quantity of the Oil, if treated at firft with 
 fpirit gives out little, or fcarcely any thing, to that menftruum. We fhall fee 
 hereafter that it is ftriCtly the gelatinous matter of animals that yields thefe 
 often five Oils ; and of this matter the proper difl'olvent is not fpirit but 
 water. 
 
 Dippel, who firft difcovered the purification and fubtilization of empyreu- 
 matic animal Oils by repeated diftillations, recommends the Oils fo rectified as 
 medicines of great virtue. Thefe Oils, in effeCt, appear to pofifefs a high degree 
 of medicinal activity : Hoffmann relates, that two drops being diflolved in half 
 an ounce of rectified Spirit of Wine, and the folution given to four men, (that 
 is, only half a drop to each) this fmall quantity procured in them all a copious 
 fweat (»). 
 
 The empyreumatic Oils diftilled from different animal fubftances are not 
 entirely the fame like the volatile Salts : Of many of them, the fmell is very ob- 
 vioufly different, not only in degree but in kind. Their particular properties 
 have as yet been very little examined, few experiments having been made upon 
 thefe fetid fubftances, except by thofe who have bufied themlelves infearching 
 for alchemical myfteries in the excremental parts of animals. Whether by 
 redification they all become perfedly fimilar, as volatile Salts do, is unknown. 
 
 Animal 
 
 (n) Animal Oils cf great medicinal activity.'^ 
 It is in confequence of the virtue of the Oil, 
 that volatile animal fpirits differ as medi- 
 cines from the pure Spirit of Sal ammoniac. 
 In the redification of animal fpirits for me- 
 dicinal ufe, the intention is not to purify 
 them wholly from the Oil, but to feparate 
 the groffer part, and fubtilize the reft, and 
 thus bring it towards the fame ftate as when 
 the Oil is redified by itfeif. I have re- 
 peated the redification of Spirit of Hartf- 
 horn twenty times fucceftively, and found it 
 ftill to participate of Oil, but of an Oil very 
 different from what it was in the firft did il- 
 lations. 
 
 able only in a low degree before ; and the 
 Alcali fhoots into cryftals, a mark that it 
 has abforbed an acid. By this method, he 
 fays, an acid principle may be demonftrated 
 in all the parts of animals. He obferves 
 likewife, that the Caput mortuum or coal 
 remaining after the diftillation of blood, 
 yields on being diftilled with Vitriol or Bole, 
 an acid fpirit agreeing in all refpeds with 
 that of common Salt ; and this though the 
 animal ufes no common Salt in its food. 
 
 May it not be prefumed, that the acid 
 difcoverable in animal fubftances by thefe 
 kinds of operations, is really no other than 
 the acid of the marine Salt which we have 
 elfewhere feen that thofe fubftances partici- 
 
Produ&s from Animal Subjlances by Fire. 
 
 Animal Oils differ greatly and obvioufly from the vegetable ; and even the 
 inflammable matter which remains fixed in the black coal left in the diftilla- 
 tion, after the expulfion of all the Oil that the greateft vehemence of fire is 
 capable of expelling in clofe veffels, appears to be different in the two king- 
 doms. Fixed alcaline Salts, calcined with coals, extradt a part of this inflam- 
 mable matter, and render it foluble along with themfelves in water : Animal 
 coals have this particularity, that when the Alcali has been calcined with thefe, 
 the folution precipitates from a folution of green Vitriol the pigment called 
 Pruffian-blue, and has different effe&s on other metallic folutions alfo from 
 other kinds of alcaline Ley. 
 
 IV. ANIMAL EARTH. 
 
 IM A L fubftances, or the black coal remaining after the diftillation of E a r t h. 
 
 them, on being burnt with a ftrong fire in open veffels, are diverted of all i — / 
 
 their volatile and combuftible matter, and reduced into a white earth. The 
 hard parts, as bones and horns, ftill retain their original figure; and inftead 
 of falling into afhes like vegetable matters, preferve l'ome degree of hardnefs : 
 
 Hence their thorough calcination is more difficult than that of vegetables, the 
 external part of the mafs defending the internal from the air. 
 
 The properties of the earths obtained by this procefs from animal and vege- 
 table fubrtances have been little examined. Thus much however, the experi- 
 ments that have been made upon them, are fufficient to demonftrate, that the 
 earths of the two kingdoms are of a quite different nature from one another. 
 
 Their differences are raoft remarkable in their habitude to vitrification. 
 
 The vegetable earth vitrifies with eafe, and gives a green tinge to its glafs, 
 which fometimes is very beautiful. The animal earth is extremely re- 
 fractory, and is fcarcely at all to be brought into perfeCt fufion, in the common 
 furnaces at Jeaft, by the moll aCtive fluxes : When mixed with the vegetable 
 earth, or with different vitreous fluxes, in fuch quantity as not to prevent the 
 fufion of the flux, it gives an opake milkinefs to the glafs, like that of fine 
 porcelane or white enamel ; the animal calx feeming to be only diffufed* 
 through the mafs without alteration of its form, juft as it would be diffufed 
 through water by agitation. From this property of animal earths, they are 
 employed in the compofition of milk-white or porcelane-like glaffes (o'). 
 
 SECT. 
 
 When previoufly diffolved in other acids, it 
 is precipitated on the addition of the vitrio- 
 lic, into a concrete no longer diffoluble in 
 any, and which is found to be fimilar to the 
 Selenitse which the mineral calcareous earths 
 produce upon the fame treatment. This 
 earth is extremely refractory in the fire : It 
 does not perfedtly vitrify (at lealt if its 
 proportion is confiderable) either with Salts 
 or with metallic glaffes ; and in this refpeCt 
 it differs from the calcareous earths of the 
 mineral kingdom, 
 
 2, The 
 
 (o) Animal earths.) In the animal king- 
 dom we meet with three kinds of earth, 
 apparently diftinCt from one another. 
 
 i. The Earth of the Shells of Jea-fifhes ap- 
 pears to be nearly of the fame kind with 
 Chalk and the mineral calcareous earths. 
 By calcination, it is changed into a true 
 Quick-lime, in fome refpeCts ftronger than 
 the mineral Limes. It diflolves readily and 
 perfedily in the nitrous, marine, and vege- 
 table acids ; but not at all, or only in an 
 inconftderable quantity, in the vitriolic. 
 
 493 
 
 Oils. 
 
[ 494 3 
 
 V 
 
 SECT. III. 
 
 INSECTS. 
 
 A MONG the infinite variety of infedts, generated fo abundantly in the 
 different parts of nature, on vegetables, on the bodies of larger ani- 
 mals, in putrid vegetable and animal fubftances, and in the earth $ 
 there are few which have hitherto been chemically examined, or applied to 
 any confiderable ufes, in medicine or in arts. The principal are, Canthavides, 
 Ants, Earth-worms, Millepedes, and Cochineal. 
 
 I. 
 
 Cantha- 
 
 RIDES. 
 
 CANTHARIDES are a beautiful kind of fly or winged i n fe<5t, of a 
 bright, fhining, greenifh-golden colour, with fome admixture of bluiffi. 
 They were formerly brought from Spain, and hence are ftill commonly called 
 Spanilh flies. They are not, however, peculiar to that kingdom : France, 
 fome parts of Germany, and other countries, produce abundance. It is prin- 
 cipally in the fpring, and on poplar and alh-trees, that they are met with. 
 
 The 
 
 2. The Allies of Bones and Horns agree 
 with the preceding in being eafily foluble in 
 the nitrous, marine and vegetable acids, and 
 not in the vitriolic ; and in their being pre- 
 cipitated by the latter from other acids 
 into a felenitic concrete. They agree alfo 
 in their refiftance to vitrification : I have 
 tried in vain to vitrifythem by the addition of 
 other earths, as well as of Salts and metallic 
 glaffes : Fufible earthy mixtures (See the 
 firft part of this work) by which all the 
 earthy and ftony bodies I know of in the 
 mineral kingdom except the precious ftones, 
 would in certain proportions have been 
 brought into fufion, were by the fame and 
 by fmaller proportions of calcined Hartlhorn 
 and of calcined Bones, either prevented 
 from melting at all, or rendered opake and 
 milky .... The difference of thefe earths 
 from the preceding, and the only difference 
 I have obferved, is, that they are not 
 changeable by fire into Lime : How ftrongly 
 foever the earth of Bones and Horns be cal- 
 cined, it continues infipid, and gives no ma- 
 nifeft impregnation to water. 
 
 3. The Allies of Blood , Skin , and Flejh, 
 
 differ from the earths of the firft kind in not 
 being convertible into Lime ; and from 
 both the firft and fecond in being diffbluble, 
 readily and perfectly and plentifully, in the 
 vitriolic acid as well as in the nitrous and 
 marine. In both thefe refpedls they agree 
 with the incinerated earth of vegetables: 
 
 # O 
 
 They differ from that earth in the nature of 
 the compound which they form with the 
 vitriolic acid ; the animal earth diilolving 
 into an auftere aftringent liquor approach- 
 ing to an aluminous nature ; the vegetable 
 into a bitter purgative one fimilar to the 
 purging mineral waters. The habitude of 
 this fpecies of animal earth to vitrification, I 
 have not tried. 
 
 The earth into which animal fubftances 
 are refolved by putrefablion appears to be one 
 and the fame whateverfubjecff itwas produced 
 from ; and not to differ fenfibly from vege- 
 table mould. It is indifloluble in acids, 
 fomewhat tenacious when moiftened with 
 water, friable when dry, and acquires no 
 additional hardnefs in the fire. The habi- 
 tude of either the vegetable or animal mould 
 to vitrification is not known. 
 
Insects. 493 
 
 The ufual way of killing them is by the fleam of flrong or diftilled Vine- Cantha- 
 gar (p). The flies are put into a clean pot, which is covered with a hair- rides. 
 cloth, and then inverted upon another pot containing the Vinegar warmed by 'w— -v— — * 
 a little lire made underneath ; the jundure of the two pots being clofely luted, 
 to coniine the Hearn. The flies are afterwards thoroughly dried, and packed 
 up fecure from the air. In long keeping, they fall by degrees into a greyilli 
 or brownifh light powder, and in this Hate are unlit for ufe, their intrinfic 
 qualities perifhing with their external form. The wings are the mo ft perma- 
 nent part, thefe remaining entire after the body of the fly has mouldered into 
 duff. 
 
 Cantharides, when frefh, have a flrong fetid lfnell : Tafled, they make at 
 firfl no impreffion upon the tongue, but in a little while they difcover a degree 
 of acrimony and a kind of pitchy flavour. Applied to the fkin, they raife a 
 blifler on the part. The ufual bliflering plafters are compofed of powdered 
 Cantharides and fome common plafter, in the proportion of one part of Can- 
 tharides to two, fix, eight or more of the plafter, according as the compofition 
 is required to be more or lefs adive. 
 
 Taken internally, in the dofe even of a few grains, they generally occafion 
 violent irritation and inflammations. They ad in a peculiar manner upon the 
 kidneys, and the urinary and feminal veflels : When applied only externally as 
 a blifler to remote parts, they often aflfed the bladder, and bring on a difficulty 
 and pain in making water. They are neverthelefs given inwardly in final! 
 dofes, both with fafety and advantage, in fome refradory diforders, which 
 baffle the force of medicines of lefs adivity. Dr. Groeneveld, who was impri- 
 foned, in England, for having ventured to exhibit them, publifhed a treatifein 
 defence of his pradice and of the utility of the medicine. He employs Cam- 
 phor for correding the virulence of the Cantharides ; but for my own part, I 
 fhould have little dependance upon that corredor : The befl remedies againfl 
 the ill effeds of this, as of other {Emulating drugs, are, Milk and exprefled 
 Oils, 
 
 The {Emulating power of Cantharides is afcribed by many to an acrimoni- 
 ous cauftic Salt. But experiment difcovers in them no faline principle of any 
 kind, till they have undergone the deftrudive adion of fire. By the adion of 
 a flrong fire, a volatile alcaline Salt is producible equally from all animal fuh- 
 ftances ; the fame Salt, and no other, is obtained from Cantharides. It is pretty 
 remarkable, that thole who deduce the virtue of this infed from an imaginary 
 Salt, employ, for extrading its virtue, not water which is the dfred and pro- 
 per menftruum of Salts, but vinous fpirits ; and thus, in their pradice, con- 
 tradid their own theory. 
 
 Others, 
 
 [p) Killed by the Jleam of Vinegar. ] Vinegar 
 fhould feem not to be very proper for this 
 ufe, for the fleam which arifes from it in a 
 gentle heat can fcarcely ad any otberwife 
 upon the infed than as a watery vapour. 
 Vinous fpirits, ufed among us for the cura- 
 tion of millepedes, appear to be the befl 
 
 calculated for the eurafion of Cantharides 
 alfo, and of other infeds, as the colouring 
 ones Kermes and Coccus Polonicus ; the 
 fleam of Spirit of Wine, or the liquor itfelf 
 fprinkled upon them, not only foon killing 
 the infeds, but embalming as it were, and 
 preferring them from decay. 
 
49 6 
 
 Insects. 
 
 Cantha- Others, in order to account for the fingular qualities of this infedt, have had 
 rides, recourfe to its mechanic ftrudlure ; to its fharp, pointed, needled, fword-like 
 V— "V*-— ' particles, lacerating the parts of animal bodies which they come in contadt 
 with. The microfcope indeed difcovers fome fine pointed filaments on the 
 belly of the fly: But thefe are only hairs, too foft and flexible to wound or 
 injure the fkin. Cantharides communicate all their adlivity to vinous fpirits, 
 without lofing any thing of their form : Bare pulverization deftroys their fpi- 
 cular appearance, without abating their acrimony or caufticity. It is not by 
 virtue of their mechanic ftrudlure, but of their intrinfic properties, that they 
 ftimulate, lacerate and corrode. 
 
 If we may be allowed, in analogy to the vegetable kingdom, to apply the 
 name of rejinous to that principle in animal fubftances which redlified Spirit of 
 Wine difiolves ; the native principles of Cantharides are, a refinous, gelatin- 
 ous, and earthy matter; and the principle, in which their adlivity folely and 
 wholly refides, is the Refin. 
 
 Four ounces of the flies, boiled in water, gave two ounces, all but two 
 fcruples, of gelatinous extradf ; after which, redlified Spirit extracted twenty- 
 eight grains of Refin, the indiffoluble earthy refiduum weighing two ounces 
 and one fcruple. The fame quantity of the flies, treated firft with fpirit, 
 yielded fix drams two fcruples of refinous extradl ; and afterwards with water, 
 three drams twelve grains of a gelatinous one : The refiduum amounted here 
 to fix drams more than in the former way of extradlion (q). 
 
 The refinous extradl is acrid and naufeous to the tafte, and blifters the fkin 
 like the fly in fubftance; whilft the gelatinous matter, freed from the refinous, 
 proves like the earthy parr, infipid and inadlive (r). In diftillation, redlified 
 fpirit brings over little or nothing : The diftilled water has a confiderable fliare 
 of tafte and fmell, but exhibits no appearance of Oil. 
 
 Three ounces of Cantharides diftilled in a retort in an open fire, gave over one 
 ounce of urinous fpirit, twodrams of empyreumaticOil, and two drams ten grains 
 of volatile Salt. The Caput mortuum weighed ten drams; and on being cal- 
 cined and elixated, yielded fcarcely a grain of faline matter It is plain 
 
 from 
 
 (q) Cantharides with water and fpirit.'] This 
 infedl communicates nothing of its fine 
 green colour to either of thefe liquors. The 
 watery tindlure is of a muddy yellowifh or 
 brownifh, and the remaining fly appears to 
 have loft confiderably of its beauty. The 
 fpirituous tindlure is of a bright yellow, but 
 leaves the Cantharides of brighter and more 
 beautiful colours than they were at firft. 
 
 There are many other animal fubftances, 
 that glow with fuperficial colours, which 
 chemiftry has not been able to feparate or 
 extradl. The coloured fhells and furs, and 
 the plumage of birds, give out nothing of 
 their colours to any known menftruum. 
 
 (r) Gelatinous part inactive.] Though the 
 
 adlivity of the Cantharides may be properly 
 faid to refide in that part which Spirit of 
 Wine difiolves ; yet this matter feems to be 
 totally extradled by water, as well as by fpirit, 
 the gelatinous fubftance rendering the other 
 foluble in water, in the fame manner as the 
 gummy parts of vegetables do the refinous. 
 An extradl made by water, an extradl made 
 by fpirit, and the flies remaining after both 
 procefies reduced into fine powder, were 
 applied at the fame time to the arm of the 
 fame perlbn : The two extradls bliftered, 
 fo far as could be judged, equally, and as 
 effedlually as Cantharides in fubftance : 
 The two refidua were equally inadlive ; 
 they did not inflame, or irritate, or fenfibly 
 aftedl the fkin, in twenty-four hours. 
 
Insects. 497 
 
 from this analyfis, that the acrimony and medicinal activity of Cantharides can Cantha- 
 have no dependence on the volatile Salt ; for we fihall fee hereafter, that much rides. 
 larger quantities of Salt are obtainable from fubftances entirely infipid and in- 
 aftive, as raw Silk, Hair, Feathers, 
 
 TH E Ant, noted by the naturalift for its agility and induftry, and its ex- II. 
 traordinary care of its eggs as they are called, in conveying them into the fun Ants. 
 fo often as he fhines, and as diligently carrying them off upon his' difappear- v— 
 ance or on the approach of rain ; affords likewife fome remarkable phenomena 
 to the chemical obferver. 
 
 On turning up an Ant-hill in fpring or fummer, the fir ft thing perceived is Volatile acid 
 a ftrong volatile fmell, affeifting the nofe nearly in the fame manner as Spirit of^ me1 ^ 
 Hartfhorn or of Sal ammoniac. This vapour is not, however, as fome have 
 toohaftily affirmed, fimilar in quality to thofe alcaline fpirits : It is truly of an 
 acid nature, and like the other fubftances of that clafs, changes the colour of 
 blue flowers, as Violets, Borage flowers, Lffc. to a red. 
 
 Onfearching the Ant-hill, we commonly find pieces of a refinous fubftance.Refm In Ant- 
 This was fuppoled formerly to poffefs peculiar virtues, and diftinguifhed by hiiJs - 
 the names of wild Frankincenfe, Suffimentum fylvejlre , thus Germanicum , majlix 
 & eleftrum formic arum. It looks, taftes, and fmells, like the common Refin of 
 the Fir-tree, and in effedt it is no other. It is about the roots of old Fir-trees 
 that Ants principally lodge-, and it is in fuch lodgments, that the Refin is 
 principally met with. For what purpofe they colledl it, I do not pretend to 
 know. 
 
 I examined, in June, above thirty Ant-hills, but did not at that feafon findTIieir food, 
 any of the corn or grain which they are laid to lay up fo plentifully for winter 
 provifion. It is not indeed on grain, but on the fweet juices of vegetables, 
 and the flefhy parts of animals that they feem to feed. A little Honey or 
 Cheefe, placed near them, will loon collect a fwarm of Ants, and by this me- 
 thod they may be catched in great numbers. They deftroy fome kinds of 
 Caterpillars on trees and on culinary plants. If a Moufe, Frog, or other like 
 animal be placed in an Ant-hill, he will be devoured in a few days to the 
 bones and ligaments. 
 
 Hence we are furnifhed with a method of obtaining fkeletons of thofe ani-Exquifite de- 
 nials, exquifitely beautiful and perfect, far furpaffing any thing that can be^F^° flmali 
 executed by artificial anatomy. The fubjeft is for this purpofe to be inclofed" 
 in a wooden box, and properly diftended, to prevent the parts from collapfing 
 or being crufhed together by the earth : The box is to be perforated with a 
 number of holes, through which the infects will prefently find their way. 
 
 The pungent vapour obferved on ftirring up an Ant-hill, does not proceed Acid of Ants, 
 from any heterogeneous fubftances, but from the Ants themfelves. If a parcel 
 of clean, live, vigorous Ants beftirred with a rod, fo as to greatly irritate and 
 exafperate them, they difcharge a fimilar acid juice, which may be plainly 
 fmelt and tafted upon the ftick. If they are thus agitated and irritated in a 
 veflel of water or of Spirit of Wine, they impregnate the liquor with their acidity. 
 
 A part of this acid is fubrile and volatile, a part grofier and more fixed. 
 
 The firft arifes in diftillation with rectified Spirit of Wine, the latter not: 
 
 S f f Thus, 
 
o • 
 
 49^ Insect 
 
 Ants. Thus, it a confiderable quantity of the fpirit be gently drawn off from the fpi- 
 i — — J 1 rituous infufion, the diftilled liquor will givefenfible marks of acidity, but will 
 not be near fo ftrongly acid as the remainder ; and hence we are enabled to con- 
 centrate this animal acid. Water aifo brings over at firft only the more fubtile 
 part, but if the diflillation be protracted, the whole of the acid arifes at length 
 along with the water, as appears from the following experiment. 
 
 Analyfis. I diftilled in a retort without addition two parcels of Ants ; one confided of 
 Ants from which water had been previoufly abftradted in balneo maria , and 
 which had afterwards been exficcated i the other of frefh Ants. Twenty-four 
 ounces of the firft yielded four ounces and a half of empyreumatic Oil, three 
 ounces and a half of urinous fpirit, two drams and a halt of concrete volatile 
 Salt, one dram of fixed alcalefcent Salt, and eight ounces of earth, without 
 giving any mark of acidity throughout the whole procels. The fame quantity 
 of frefh Ants on the other hand, gave over firft of all eleven ounces and two 
 drams of an acid fpirit, afterwards fix ounces fix drams of an urinous one, one 
 ounce and a half of empyreumatic Oil, and a dram and a half of concrete vola- 
 tile Salt : The remaining earth weighed nearly three ounces, and yielded half a 
 
 fcruple of fixed Salt It is plain from hence, that the acid of Ants is 
 
 capable of being wholly elevated by diflillation with water even in balnea 
 maria. 
 
 The grofs acid is as ftrong as good Vinegar : It changes Syrup of Violets 
 red ; effervefces with alcaline Salts and precipitates fubftances diffolved by 
 them ; diffolves abforbent Earths, Iron, and feveral other metallic bodies. 
 
 Mr. Hook obferves that fome other infedts which are furnifhed with ftings, 
 as Bees, Walps, Hornets, are furnifhed alfo with an acid juice, which they dif- 
 charge upon being irritated ; but none yield fo large a quantity as Ants. Ants 
 in their chryjalis or maggot ftate have no acid ; no marks of any having been 
 difcovered on diftilling a quantity of the eggs. 
 
 I Hernial Oil Another very extraordinary phenomenon occurred in a chemical examina- 
 tion of this infedt. Having diftilled off fome redtified Spirit of Wine from a 
 quantity of Ants, and cohobated the fpirit upon two or three frefh parcels, I 
 found fwimming upon the diftilled liquor, a fine, clear, effential Oil. 
 
 Effential Oils are extreme rarities in the animal kingdom : There are only 
 
 fome fubftances of the undhious kind that yield any thing like one : The Oils 
 
 obtained from thefe are rather thin Fats than true Oils •, and fuch as they are, 
 they do not arife without a confiderable fire, whilft this Oil came over with highly 
 redtified fpirit in the heat of a water-bath. I fufpedted therefore that it was no 
 animal Oil ; that it proceeded from fome fmall bits of wood or of the refinous 
 fubftance above-mentioned, from which the Ants had not been fufficiently 
 cleanfed. The fmell and tafte feemed likely to determine this ; and here again 
 I was furprized, to find that it had nothing of the pungency or heat which 
 accompanies the Oils of Refins and Woods. For further certainty in this 
 point, I made a frefh diftillation from Ants very carefully picked, and well 
 vvafhed with fpirit : I diftilled alfo fome ounces of the Refin with Spirit, in the 
 heat of a water- bath, after the fame manner as the Ants. The Ants yielded as 
 before an effential Oil, whilft the Refin gave over fome flavour to the fpirit, 
 but no vifibie Oil. It was now evident, that the Oil did not proceed from 
 
 hetero- 
 
Insects, 499 
 
 heterogeneous matters adhering to the Ants : But there was (till a poffibility Ants. 
 
 that it did not pre-exift: in the infedt. When Spirit of Wine is diftiiled with 1 — ^ 
 
 the vitriolic acid, an Oil is extricated from the fpirit : It was polhble that the 
 acid of Ants might have here produced a fimilar eftedf. I therefore diltilled 
 another parcel of well cleanfed Ants, with pure water inftead of Spirit : The 
 
 experiment was fully decifive : 1 Hill obtained the fame Oil, a truly animal 
 effential Oil (j). 
 
 Ants 
 
 (9 EJfential Oil and acid of Ants.'] Mr. 
 Marggraf, in the Berlin Memoirs for the 
 year 1749, has given fome further obferva- 
 tions on thefe fingular products, and difco- 
 vered alfo another principle in the Ant, no 
 lefs rare in the animal kingdom, an Oil of 
 the expreffible kind, fimilar to the exprefled 
 Oils of vegetables. 
 
 A quantity of live Ants was put into wa- 
 ter, and diftiiled in a glafs retort with a fire 
 gradually railed to ebullition : In the recei- 
 ver was found an acidulous liquor, with an 
 eftential Oil fwimming upon it, as difco- 
 vered by Neumann. This Oil had a pecu- 
 liar fmell, but no burning tafte : Mixed and 
 digefted with Salt of Tartar, and with iron 
 filings’, it gave no mark of acidity : It totally 
 diflolved the folid Phofphorus of Urine, but 
 without becoming luminous: It united with 
 Spirit of Wine that had been diftiiled from 
 fixed alcaline Salt, but did not mingle with 
 a fpirit rectified per fe. 
 
 The acid decoftion, which remained in 
 the retort, being prefled out from the Ants, 
 there appeared upon its furface an oily mat- 
 ter ; the quantity of which was found, in 
 repetitions of the experiment, to be at leaft 
 an ounce and a half or two ounces from fix 
 quarts of Ants. This Oil was of a reddifh- 
 brown colour, and fmelt a little of the in- 
 fe£t : In a temperate air it appeared fluid 
 and tranfparent, but in a moderate froft it 
 became thick and opake : Like other ex- 
 prefled Oils, it burnt with a wick ; fwum 
 on water, and refufed to mingle with it ; 
 did not unite with the moft highly rectified 
 Spirit of Wine ; did not arife in diftillation 
 with water ; diflolved Sulphur by boiling ; 
 formed a pi after with calx of Lead, and a 
 perfedt Sope with alcaline Salts. 
 
 The acid decodtion, freed from the Oil, 
 was diftiiled in a retort placed in fand : The 
 receiver was changed as foon as the drops 
 came over very acid ; and the procefs dif- 
 
 continued as foon as they became empyreu- 
 matic. By this means was obtained a li- 
 quor both in fmell and tafte highly acid; 
 the thick black Caput mortmain remaining 
 alfo confiderably fo. 
 
 Properties of the acid of Ants. 
 
 QpHE acid of Ants eftervefces with alca- 
 A line Salts, both fixed and volatile. 
 With volatile alcalies it forms a neutral 
 liquor, which (like that compofed of the 
 fame alcalies and Vinegar) yields no con- 
 crete Salt in diftillation. 
 
 With fixed alcalies it concretes, upon 
 proper exhalation, into oblong cryftals, 
 which deliquiatc ill the air. The cryftals, 
 or the faturated neutral liquor uncryftailized, 
 on being diftiiled with a fire increafed till 
 the retort begun to melt, yielded a liquor 
 fcarce fenfibly acid, and afterwards a fmall 
 quantity of an urinous and partly ammonia- 
 cal liquor. The remaining black matter, 
 diflolved in diftiiled water, filtered and eva- 
 porated, fhot into large cryftals, of a parti- 
 cular figure, and which did not liquefy in 
 the air, though they were in tafte ftrongly 
 alcaline, effervefced with acids, and had all 
 the other properties by which fixed alcalies 
 are diftinguifhed. 
 
 This acid diftolves, with great efferve- 
 scence, Coral, Chalk, and Quick-lime ; 
 and concretes with them all into cryftals, 
 which do not deliquiate in the air. 
 
 It does not precipitate Silver, Lead or 
 Mercury from the nitrous acid ; nor Quick- 
 lime from the marine. Hence it appears to 
 have no analogy to the marine or vitriolic 
 acids ; the firft of which conftantly precipi- 
 tates the metallic Solutions, and the other 
 the earthy. 
 
 It does not act upon filings of Silver ; but 
 (like vegetable acids) it totally diftolves, by 
 the afliftance of heat, the calx of Silver pre- 
 f 2 cipitatetf 
 
5 °° 
 
 Insects. 
 
 A n t s. Ants have been employed medicinally as an ingredient in baths for weaknefs 
 — V-— — ' of the nerves, rheumatic, paralytic, and other like complaints. Vinous fpi- 
 rits, impregnated by diftillation with their volatile parts, have been applied 
 externally to the fame purpoles, and likewile taken internally, as attenuants, 
 corroborants, and aphrodifiacs. Many other preparations oPthis infe£t for the 
 like ufes are defcribed in the old books of pharmacy. 
 
 Deftroyed. Ants are deftroyed by ftrewing a good quantity of unflaked Lime about their 
 hills: Some make ufe of Quickfilver, as a general poifon to infeds. It is faid 
 that they fly from Chalk, and from Ants that have been burnt ; but on trial, 
 I could not find that they did. 
 
 jip EARTH-WORMS are inhabitants of moift fat grounds, and are rarely 
 Earth- or never feen in dry kinds : After rains, they come up to the furface, to enjoy 
 worms, the moifture, and there they often fall a delicious prey to different kinds of 
 <_ — „ — ._■» birds (t). It is only when the lurface of the earth is moiftened by artificial 
 watering, by rain, or the dew in fummer-evenings, that we catch them: Some 
 employ for watering the ground a decoition of Hemp-feed or of Walnut leaves : 
 The Worms have great lenfibility of any motion of the earth about them from 
 a rude approach, and in the twinkling of an eye are funk into their holes again. 
 They can fcarcely bear any faline fubltances, except thofe of the nitrous and 
 urinous kind : A folution of Vitriol, or of common Salt, or alcaline Ley, 
 
 poured 
 
 cipitated from Aqua fortis by Salt of Tartar. 
 
 It does not dilTolve calces of Mercury, (as 
 vegetable acids do) but revives them into 
 running Quickfilver. 
 
 It a£ts very weakly upon filings of Cop- 
 per, but perfectly difiolves Copper that has 
 been calcined. The folution yields beauti- 
 ful, compact, green cryftals. 
 
 It difiolves iron filings with violence. 
 The folution, duly evaporated, fhoots into 
 cryftals, more readily than that made in di~ 
 ftilled Vinegar. 
 
 It fcarcely a£ts at all upon calces or filings 
 cf Tin. 
 
 It dees not, according to Mr. Marg- 
 graf, corrode filings of Lead ; but difiolves 
 by the affiftance of heat, the red calx of 
 Lead. The folution cryftallizes into a Sac- 
 charum faturni . . . In Mr. Ray’s philolophi- 
 cal letters it is faid, that Lead put into 
 “ the acid fpirit, or fair water together with 
 “ the animals themfelves being alive, makes 
 “ a good Saccharum faturni,” and that this 
 Saccharum on being dificilled “ will afford 
 “ the fame acid fpirit again, which the Sac- 
 “ charum faturni made with Vinegar will 
 “ not do, but returns an inflammable Oil 
 “ with water, but nothing that is acid : 
 “ And Saccharum faturni made with Spirit of 
 
 “ Verdegris doth the fame in this refpeCt 
 “ with Spirit of Pifmires.” 
 
 It difiolves Zinc with vehemence; and 
 fhoots, upon duly evaporating the folution, 
 into elegant cryftals, not at all like thofe 
 produced with diftilled Vinegar. 
 
 It feems to have little efteCt upon Bif- 
 muth or Regulus of Antimony, either in 
 their metallic form, or when reduced into 
 calces. 
 
 From thefe experiments it appears, that 
 this acid has a great analogy with that of 
 Vinegar, though in fome refpe&s it is dif- 
 ferent. 
 
 (/) Earth-worms as food for birds f Mr. de 
 Reaumur propofes the collecting of Earth- 
 worms for feeding domeftic fowls, in the 
 room of grain. He computes, that the 
 quantity of Worms lodged in the earth is 
 greater than the fum total of every kind of 
 grain reaped by men. He oblerves, that 
 during the whole courfe of the year they 
 make greateft part of the food of numerous 1 
 kinds of birds, many of which have in win- 
 ter fcarcely any other refource ; and that 
 there would ftill remain enow for the wild 
 birds, if we were to give all our domeftic 
 fowls no other aliment. 
 
Insects. 501 
 
 poured into their holes kills them •, but that nitrous and putrid matters are not 
 offenfive to them, appears from their loving dunghills. Their food is the 
 young and the corrupted roots of plants. 
 
 Earth-worms are cleanfed, for medicinal ufe or chemical experiments, by 
 wafhing, and then fuffering them to creep through coarfe woollen cloths. Un- 
 lefs haftily dried, by the heat of the fun or of common fire, they are very apt to 
 putrefy, on account of their copious flimy juice, Moiftened with Wine or 
 with vinous fpirits to prevent their putrefa&ion, and fet in a cellar in a wide- 
 mouthed glafs, they are almoft wholly refolved in a few days, into a flimy 
 liquor. Stahl fuppofes that they are impregnated with a nitrous Salt, which 
 they receive from the putrid matters they live among : When the liquamen or 
 dilfolution of the Worms is mixed with a little fixed alcaline Salt, and after due 
 evaporation fet by to fhoot, the crydals are no other than Saltpetre. 
 
 On digeding dried Earth-worms in frefh parcels of rectified Spirit of Wine, 
 fo long as they communicated any tinge to the mendruum, and then infpif- 
 fating the tindfures together by a gentle heat ; I obtained, from four ounces of 
 the Worms, fix drams of extradt: The refiduum dried and treated with water, 
 gave out three drams and a fcruple. The fame quantity of the dry Worms, 
 treated at firfl with water, yielded one ounce fix drams and a fcruple ; after 
 which, rectified fpirit extracted two fcruples. So that the quantity extracted 
 by water is not only greater than by redtified fpirit, but the colledtive quantity 
 extradled by both menftrua is greater when water than when fpirit is applied 
 fird. 
 
 Thirty-two ounces of dried Earth-worms, diddled in a retort without addi- 
 tion, by an open fire, yielded thirteen ounces and a half of volatile urinous 
 fpirit, one ounce of concrete volatile Salt, and four ounces and a half of em- 
 pyreumatic Oil : The remainder, burnt in the open air, and elixated with wa- 
 ter, gave an ounce and a half of fixed alcaline Salt : The earthy part weighed 
 fix ounces and a half. If the infects be putrefied previous to the didillation, 
 they give over almoft mere phlegm, or only a very little Oil and volatile Salt. 
 
 Earth-worms are fuppofed by fome phyficians to be antifpafmodic and diu- 
 retic : In cafes where inch medicines are required, they have been given in 
 
 powder, from fifteen grains to a fcruple. What medicinal virtues they really 
 poflefs, it is not my province to enquire ; but whatever thefe virtues may be, it 
 is in the fixed and not in the volatile parts that they refide : The diddled water 
 and fpirit, though greatly recommended by fome, are entirely infignificant, as 
 having no impregnation from the Worms, 
 
 Earth-worms burnt to blacknefs in aclofe veflfel, are faid to be more lervice- 
 able in nervous cafes, than in their natural date, or than fuch preparations of 
 them as have not iuffered a like change from fire ; and fundry other animal 
 fubdances, prepared in the fame manner, are fuppofed to acquire fimilar an- 
 tepileptic virtues. Thefe kinds of preparations are not to be confidered as pof- 
 fefiing any of the fpecific qualities of the fubjedt from which they were made ; 
 but as an animal coal, not diveded of thofe principles which a longer continu- 
 ance of the fire would have more completely formed and extricated from it. 
 
 The medicinal efFetfts of fuch a coal, in which the volatile Salt is jud as it were 
 a forming, are not perhaps much known, any more than its chemical properties, 
 
 MIL- 
 
 Earth- 
 
 worms. 
 
2 J 
 
 5 °2 
 
 Insects. 
 
 iv. 
 
 ILLEPED 
 
 — *"% *»*'- 
 
 MILLEPEDES or Woodlice are oblong infeCts, commonly as long 
 s ; again as they are broad ; flat and whitifh on the belly ; fomewhat convex, and 
 J of a paler or darker brown colour, on the back; and indented about the Tides 
 like a Taw. The number of feet, though their ufual Latin name Millepedes ex- 
 prefies their having a thoufand, is only fourteen, feven of which are on one 
 fide, and as many on the other. The back is compofed of joints, like a Lob- 
 fter’s tail ; by means of which, the animal contrails itfelf into a globular form 
 on being touched, or on the apprehenflon of any danger. The eggs are white 
 and gliftening, like little Pearls. 
 
 They are met with in moil! places, as in cellars, about old rotten wood, 
 about water troughs, under timber and itones that have lain long on the 
 ground unmoved. Their fize is different in different places and countries : 
 Thofe found about houfes are larger than in the cavities of trees in woods, 
 and thofe of France larger than thofe of Germany: The largeft are the belt. 
 
 Snakes, Lizards, Frogs and Toads devour them. 
 
 Watery liquors extraCt from this infeCb, as from the foregoing, confiderably 
 more than fpirituous ones ; though the quantity of matter, foluble in either, is 
 not near fo large in the Wood-loufe as in the Earth-worm. From an ounce of 
 Millepedes I obtained by water four fcruples and fffteen grains of extract, whilft 
 the fame quantity, treated with rectified fpirit, gave but two fcruples and 
 twelve grains. After the fpirit would extract no more, water took up two 
 fcruples and five grains : But the Millepedes that had been firff digefted with 
 water, gave out to fpirit only half a fcruple. The indifloluble matter, re- 
 maining after the aCtion of both menffrua, weighed when fpirit was applied firff, 
 fix drams four grains ; when water was firff applied, five drams and a half. 
 
 Four ounces of Millepedes, diftilled in a retort with an open fire, gave 
 over ten drams and a half of urinous fpirit, three drams and a half of empy- 
 reumatic Oil, and a fcruple of concrete volatile Salt : From the remaining 
 
 coal, burnt in the open air, and elixated with water, were obtained three fcruples 
 and a half of fixed alcaline Salt, and two ounces of earth. A little more vola- 
 tile Salt may be feparated from the fpirit : But the quantity does not, in all, 
 amount to near fo much as Lemery makes it : If no miftake was made in his 
 experiment, the Millepedes of France muff be different in quality from thofe of 
 Germany which I examined. 
 
 It is commonly fuppoled that this infect contains a nitrous Salt, from its liv- 
 ing in cellars, and other places imagined to be impregnated with Nitre. No 
 luch Salt, however, is to be difcovered by experiment, either in the Millepedes 
 themfelves, or in the earths where they are found. 
 
 Millepedes are celebrated medicinally as relolvents and diuretics ; and fup- 
 pofed to have tins peculiar advantage, that whilft they effectually promote urine 
 and attenuate vifcid juices, they occafion no immoderate heat or exagitation of 
 the humours: It may be queftioned, perhaps, whether this quality is deduced 
 Irom fair experience, or Irorn the conceit of their being impregnated with a 
 nitrous Salt. 
 
 The powder of Millepedes is faid to be lefs efficacious than the freffi infeCt, 
 or its juice, or an infufion of it in Wine or in vinous fpirits. Whatever the 
 
 Mil- 
 
Insects. 503 
 
 Millepedes may lofe in being dried and powdered, it is pretty clear that nothing MuiIfED,, i 
 of their virtue arifes in diftillation ; for neither the diddled water nor fpirit f—-* 
 have any fmell or tafte. 
 
 C O C H I NEAL is a fmall, irregular, roundifh body, internally of a red V. 
 colour. It is brought chiefly from New Spain, and there colledted from aCocmNEAL. 
 plant, which is now common in the botanic gardens of Europe, called Opuntia — v— 
 
 or prickly Pear-tree. history. 
 
 It was formerly fuppofed to be the entire fruit or berry of the tree, wrinkled 
 and fhrivelled by drying : When the Pear itfelf became known, Cochineal was 
 fuppofed to be its feeds •, but it differs greatly from thefe alfo, as well as from 
 the entire Pear. It is now known with certainty, to be not a vegetable but an 
 animal fubdance •, to be a particular fpecies of infedt, produced upon the tree. 
 
 Acofta was one of the firft eye-witneffes of its being an infedt ; and Sir Hans 
 Sioane, Plunder, and all the later travellers into America, confirm his 
 
 account. 
 
 To what clafs of infedts Cochineal belongs, has been difputed ; fome affirm- 
 ing that it has fix feet, and no wings, and refembles a Bug; others, that it 
 has four wings, and is a fpecies o i Scarab reus or Lady-bird ; others, that like 
 feveral kinds of Caterpillars and Worms, it has neither wings nor feet; and 
 others, that it is an infedt in its imperfedt or chryfalis date, inclofed in a pellicle 
 or hulk. All thefe opinions are in part true : The Cochineal infedt, like many 
 others, goes through a variety of forms; though the rich red colour, for which 
 it is valued, it poflelfes only in one of them. On examining carefully feve- 
 ral hundred weights of Cochineal as brought to us, I have feen fome grains in 
 all the dates above-mentioned. 
 
 In its advanced date, it is a fmall fcarabasus, or fheath- winged infedt with 
 fix feet : The body is roundifh, hemifpherical on the upper part, flat under- 
 neath, full of circles or rings, of a blackilh-brown colour : The covers of the 
 wings are red, with a yellow fpot on each. The fcarabaeus depofites on the 
 leaves of the Opuntia, fmall eggs, from each of which comes forth a little in- 
 fedt, refembled to a Flea or Tick. When this increafes, it looks like a Worm 
 or Caterpillar, with fix fmall feet, fcarcely to be feen, on the forepart of its 
 body: It crawls among the leaves, and chules fuch fituations, where it may 
 be bed fecured from rain and other inclemencies of weather. After thefe have 
 attained to their full growth, they contradt themfelves, and at the fame time 
 become redder and redder : A pellicle is formed all over them, and they ad- 
 here motionlefs, as if fixed with Glue, upon the leaves, which now look as if 
 covered with fine red berries. This date continues about ten or twelve days, 
 when the hufk opens, and difcovers a winged fcarabaeus again, which has very 
 little of the deep red colour of the Maggot or chryfalis. The fcarabaeus lays 
 its eggs, and then fucceed the fame transformations as before. 
 
 Great care is taken in the prefervation and curation of thefe valuable in- 
 fedts ; in defending them from rain, cold, heat, from being preyed on by 
 birds, fsk. in houfing them at certain feafons, and in colledting and drying 
 them for ufe : The particular methods, followed for thefe purpofes, are not 
 certainly known. 
 
 The 
 
5°4 Insects. 
 
 Cochineal. The infedt is doubtlefs collected in its red imperfedt Maggot- ftate ; and 
 hence the grains of Cochineal, as brought to us, have rarely any appearance 
 either of feet or wings : If taken whilft fome of them are ftill crawling about, 
 or if the colledtion is deferred till fome of them are transformed into winged 
 fcarabaei, the quality of the Cochineal is debafed in proportion to fuch admix- 
 ture. Some report, that the berries, as they are called, are taken off from the 
 leaves by means of certain inftruments •, but how the fkins or hulks are fepa- 
 rated, we have no account. In the Philofophical Tran factions, No 193, it is 
 faid, that a fmoky fire is made on the windward-fide of the tree ; and that the 
 infedts, killed by the fmoke, fall lpontaneoufly or are eafily fhaken off, upon 
 linen fheets lpread underneath, and are afterwards dried in the fun. Ruiefcher 
 mentions three ways of killing them ^ one by hot water, which renders them 
 brown on the outfide •, another, on hot iron fhovels, which fcorch them to a 
 blackifh hue; and the third in ovens, where they acquire afh-coloured varie- 
 gations. Others report, that after they have been killed by the fleam of hot 
 water, hot allies are ftrewed upon them, and that the white colour is owing to 
 thele: There is no probability of this; for I have myfelf taken feveral of the 
 grains out of their external involucrum or hulk, and found them naturally 
 ftreaked with white; befides that this whitcnefs is greater than that of allies, 
 and is not to be rubbed off, as allies externally adhering would be. 
 
 Frefh Cochineal lofes in drying about two thirds of its weight : I have made 
 the experiment with from three to four pounds, which by drying were reduced 
 to fixteen and eighteen ounces. 
 
 Different The dried Cochineal is forted into large entire grains, and fmall or broken 
 forts. ones : The firft are called by the Spaniards Gram, the latter Granilla. In trade 
 
 four forts are diftinguifhed, Mefieque , Campefchane , Tetrefchale , and Sylvejter ; of 
 which the firft is accounted the beft and the laft the worft : The three former 
 are named from the places where they are produced ; the latter, from its being 
 found wild, without any culture. The differences in the cultivated Cochineal 
 are very confiderable, depending partly upon the climate and feafon, partly 
 upon the curation, and partly upon the fpecies of plant. 
 
 The fruit of the Opuntia itfelf is of a red colour, and is faid, when eaten, to 
 tinge the urine red : Thofe forts, whofe fruit is of the deepeft red colour, are 
 oblerved to produce the fineft Cochineal. Sir Hans Sloane diftinguifhes the 
 beft fpecies by the name of Opuntia maxima , folio oblongo rotundo majore , fpinulis 
 obtufis mollibus & innocentibus obfito , flore finis rubris variegato , the very large 
 Opuntia, with an oblong roundifh large leaf, befet with foft blunt harmlefs 
 fpines, and a flower variegated with red ftreaks. In the Memoirs of the 
 French Academy for the year 1714, another fpecies is preferred, namely, that 
 called by Tournefort Opuntia major validijfimis fpinis five aculeis muni t a, the 
 greater Opuntia armed with very ftrong fpines or prickles. 
 
 The beft Cochineal is fomewhat heavy, or at leaft not very light, moderately 
 compadt, clean, dry, of a gloffy furface, of a dark blackilh red colour on the 
 outfide, with white filver-like ftreaks. Chewed, it tinges the fpittle of a deep 
 brownifh-red colour, and impreffes a kind of faint not agreeable tafte. When 
 thoroughly dry, it has no l'mell ; when moift, a fomewhat mufty one. 
 
 A tine- 
 
Insects. 505 
 
 A tincture drawn from powdered Cochineal by digeftion with water, was Cochineal. 
 very gelatinous : Out of four drams of Cochineal, one dram remained undif- 
 folved, and the extract obtained by evaporating the liquor weighed three drams. 
 
 The fame quantity, digefted with redified fpirit, yielded two drams two fcruples 
 and a half of extrad, or half a fcruple lefs than with water-, the refiduurn be- 
 ing half a fcruple more. The fpirit, drawn off by difcillation, was found to 
 have received no change the difrilled water had greateft part of the mufly 
 fmell of the in fed. 
 
 The tindure of Cochineal by itfelf is of a much weaker red colour than when Colour ex- 
 certain faline additions are employed : Volatile alcalies in particular not only traded and 
 render the colour deeper and richer, but at the fame time incline it rather to a ini P roveci - 
 purple than to a pure red -, whilft acids brighten, and if their quantity is large, 
 deftroy it. The fpirituous tindure is of a finer red than the watery. I have 
 made eighteen other experiments with different faline liquors and folutions, 
 but as nothing very remarkable was obferved, I fhall not relate them here. 
 
 An ounce of Cochineal, diftilled in an open fire very gradually and cauti- Anatyfis by 
 oufly increafed, gave over firft two fcruples and three grains of mere phlegm, fire, 
 then four fcruples of an urinous fpirit, and fifteen drops of an oily fpirit, fol- 
 lowed by twenty- two grains of volatile Salt, and five fcruples two grains of 
 empyreumatic Oil : The Caput mortuum weighed two drams two fcruples, 
 and yielded five grains of a fixt lixivial Salt. 
 
 Cochineal has been fuppofed to poffefs fome medicinal virtues, but its prin-jjp es 
 cipal ufe is as a colouring drug. It is with this infed, that feveral of the red 
 tindures, waters and fpirits of the (hops are tinged ; that fcarlets and fiery reds 
 are dyed upon (ilk and woollen ; that Spanifh wool ufed for a fucus, and 
 fome kinds of the red Turnfol rags, are ftained ; that Carmine, and fome other 
 fine red lakes, are prepared for the painter. The preparation of Carmine is 
 defcribed by Homberg in the Hiftory of the French Academy publifhed by du 
 Hamel, pag. 345. but th tChouan and Autour , mentioned there, are now omit- 
 ted — —This drug is extremely rich in colour: Boyle informs us that a fingle 
 grain, extraded by Spirit of Urine, gave a red tindure to 125000 times its 
 quantity of water (u). 
 
 SECT. 
 
 [u) Hiftory of Cochineal as a dying drug.] 
 Cochineal, infufed or boiled in water, im- 
 parts a crimfon tindure, inclining to purple. 
 After the more foluble parts have been 
 got out by light infufion or codion, the 
 tindures extraded from the remainder by 
 fucceffive frelh parcels of water, have more 
 and more of a purple hue. Woollen cloth, 
 prepared by boiling with a little Alum and 
 Tartar, acquires a crimfon dye on being 
 boiled with a proper quantity of Cochineal 
 in fine powder. 
 
 The beauty of crimfon, as Mr. Hellot 
 obferves, (from whofe Art deteindre , great 
 Dart of the remainder of this article is ex- 
 
 T 
 
 traded) is to incline as much as poflible to 
 the gridelin, or to be extremely deep. Fixed 
 alcaline Salts give the defirable deepnefs, 
 but tarnifh the colour and diminifh its hi ft re. 
 Volatile alcalies have the fame good effed 
 as the fixed, without their bad one ; but the 
 great volatility of thefe Salts occafions them 
 to be fo plentifully diffipated from the hot 
 liquor, that a very large quantity would be 
 neceffary to effedually anfwer the purpofe. 
 Mr. Hellot, however, has difcovered a me- 
 thod of applying them to good advantage : 
 The cloth, dyec! crimfon in the ufual man- 
 ner, is dipt in a folution of a little Sa! am- 
 moniac ; and as foon as the liquor grows 
 t t moderately 
 
5°6 
 
 Insects. 
 
 Cochineal, moderately warm, a quantity of Pot-afh, 
 v—— ^ equal to that of the Sal ammoniac, is 
 thrown in: The volatile alcali of the Sal 
 ammoniac is inftantly extricated, and com- 
 municates to the cloth the brilliancy and 
 deepnefs required. 
 
 A fmall quantity of the vitriolic acid, 
 dropt into a decoction of Cochineal, changes 
 it to a purple : On adding more and more 
 of the acid, the liquor becomes flefh-co- 
 Joured, and at laft colourlefs. Spirit of 
 Nitre, in like manner gradually dropt in, 
 fiift inclines the colour to yellow, then turns 
 it quite yellow, and at laft almoft deftroys 
 it ; the acid cliftolving or attenuating the 
 colouring particles, fo as to render them 
 indiftinguifhable by the eye. 
 
 Solution of Tin in Aqua regis heightens 
 the colour into a fcarlet, more or lefs fiery, 
 that is blended with more or lefs of a yel- 
 low hue, in proportion to the quantity of 
 the folution : The liquor, thus heightened, 
 communicates its own fcarlet colour to 
 woollen cloth prepared by boiling with 
 Tartar. 
 
 Other metallic folutions have not this 
 effecft. Zinc difTolved in Spirit of Nitre 
 changes the led of Cochineal to a flaty vio- 
 let : Solution of Bifmuth in Spirit of Nitre, 
 diluted with an equal quantity of water, and 
 dropt into a deception of Cochineal, pro- 
 duced on prepared cloth dipt therein a very 
 beautiful and lively turtle-grey : A folution 
 of Copper in Spirit of Nitre, undiluted, gave 
 a dirty crimfon : Solution of cupelled Silver, 
 a fomewhat tawny Cinnamon colour : So- 
 lution of Gold, a kind of marbled chefnut, 
 the cloth appearing as if compofed of Wool 
 of different colours : Solution of Mercury 
 in Spirit of Nitre, nearly the fame : Tinc- 
 ture of Bifmuth -ere in Spirit of Nitre, a 
 purple almoft violet, as beautiful as if the 
 Cochineal had been applied upon cloth pre- 
 vjoufly dyed of a fky-blue. Vitriolated Tar- 
 tar deftroyed the red colour of the Cochi- 
 neal, and produced a grey, though the in- 
 gredients of that Salt, feparately, have a 
 different effedb. 
 
 The dyers are faid to prepare their feta- 
 tion of Tin for fcarlet, by pouring upon the 
 metal a quantity of Aqua fortis diluted with 
 water ; with the addition fometimes of a 
 little Nitre, which is fuppofed to contribute 
 fomewhat to the uniformity of the colour. 
 We have foimerly feen (page 87.) that 
 
 Aqua fortis does not perfectly diflblve this 
 metal ; and what it does diflblve at firff, it 
 foon depofites again, in form of a thick 
 Mucilage ; the clear liquor retaining fcaicely 
 any thing of the metal. The proper men- 
 ftruum of Tin is Aqua regia, or a mixture 
 of the nitrous acid either with the marine, 
 or with neutral Salts containing it, as com- 
 mon Salt and Sal ammoniac. If eight 
 ounces of Spirit of Nitre be diluted with an 
 equal quantity of water, and half an ounce 
 of Sal ammoniac and two drams of Nitre 
 difTolved in the mixture; the menftruum fo 
 prepared will difiolve, and keep difTolved, 
 about an ounce of Tin, provided the metal 
 be previoufly reduced into grains or fmall 
 parts, and very leifurely dropt into the li- 
 quor, grain by grain, waiting till one is 
 difTolved before another is put in. This fo- 
 lution depofites no Mucilage : It becomes 
 indeed opake and milky in the great heats 
 of fummer, but, in cold weather it refumes 
 its limpidnefs and tranfparency ; and even in 
 its milky ftate, Mr. Hellot fays, it is found 
 to anfwer as well in every refpedl for dying 
 fcarlet as when it is transparent; whilft the 
 folutions made in the common manner, 
 when once they have grown thick or opake, 
 which they do in a day or two or lefs, can- 
 not be employed at all for that ufe. 
 
 Woollen cloth requires, for being dyed 
 fcarlet, about one fixteenth its weight of 
 Cochineal ; a part of which is ufed along 
 with the Tartar in the preparatory liquor, 
 from which the cloth receives a lively flefn- 
 coJour ; and the reft for finifhing the dye ; 
 a fuitable quantity of the folution of Tin 
 being added in both decodlions. 
 
 1 lie copper vefiels, employed for the dy- 
 ing of other colours that require boiling, are 
 lefs proper for fcarlet ; the acid liquor be- 
 ing apt to difiolve a part of the Copper, 
 which precipitates a proportionable quan- 
 tity of the Tin, and deadens the colour and 
 flams the cloth. 1 in vefiels are commonly 
 made ufe of, and are undoubtedly the moft 
 fafe and certain : Their expenfivenefs how- 
 ever, and the great precaution neceflary to 
 keep them from melting, have induced 
 feme of the French dyers to fearch for 
 means of making the procefs fucceed in 
 Copper ones : By keeping the coppers ex- 
 tremely clean, and confining the cloth in 
 a net fo as not to touch the fides, they are 
 faid to have produced fcarlets fcarcely, if at 
 
 all 
 
C T S. 
 
 I N S E 
 
 5 ° 7 
 
 at ail inferior to thofe dyed in Tin vef- 
 fels. 
 
 The fcarlet proves darker or of a more 
 fiery orange colour, according as the folu- 
 tion of Tin is ufed in fmalJer or larger 
 quantity. Hence too great darknefs is ea- 
 fily remedied by adding more of' the; folu- 
 tion ; the cloth being previoufty taken out, 
 and the additional acid mixed thoroughly 
 with the liquor before it is put in again. 
 Scarlet which has too much fire is darkened 
 by palling it through warm water ; and if 
 the excels is greater than this can remedy, 
 by diflolving in the water a little Alum ; 
 out the injury which an over-proportion of 
 the acid folution does to the cloth, is irre- 
 mediable. 
 
 Some of the French dyers give fire to 
 their fcarlets, without any injurious quan- 
 tity of the acid, by the addition of a yellow 
 drug, Turmeric; but the luftre which the 
 Turmeric gives, like the dye of Turmeric 
 by itfelf, foon perilhes. It is obfervabie 
 that the fcarlet dye is' only fuperficial, the 
 internal part of the cloth being white ;When 
 yellow drugs are added, they do not make 
 the fcarlet fink, but fink themfelves through 
 the whole fubftance of the cloth, and thus 
 are readily difcovered upon cutting. 
 
 All urinous and alcaline fubftances ftain 
 fcarlet to a crimfon, by deftroying the effect 
 of the acid : If fcarlet cloth be boiled in al- 
 caline Ley, it becomes firft crimfon, then 
 purplifh, and on continuing the codtion 
 gives out the whole of its colour to the li- 
 quor; from which the colouring matter 
 may be precipitated, by adding a folution of 
 
 Alum, into a crimfon lake. Hence in 
 
 pure country air, fcarlet retains its luftre 
 much longer than in large cities where alca- 
 line and urinous vapours are more abun- 
 dant. The dirt of roads, and fundry fub- 
 ftances of the acrid kind, leave no ftain in 
 fcarlet, if the part be wafhed immediately 
 with pure water and a white linen cloth. If 
 the dirt is fullered to dry, a blackifh violet 
 fpot will remain, which can be taken out 
 only by mild vegetable acids, as Vinegar, 
 Citron-juice, a warm dilute folution of 
 white Tartar, or four bran-water : If thefe 
 acids, however, be not applied with a good 
 deal of addrefs, whiift they take out the 
 blackifh ftain, they leave a yellow one, by 
 difiolving the colouring particles of the 
 Cochineal itfelf. 
 
 T 
 
 It is obfervabie, that if a piece of fcarlet 
 be boiled in the liquor by which cloth is 
 prepared for receiving this dye, it lofes im- 
 mediately great part of its colour ; which, 
 if frcfh pieces of white cloth are boiled 
 along with it, will be imbibed by them, and 
 equally diftributed among them ali. After 
 the boiling has been continued about an 
 hour, it will be difficult to diftinguifh that 
 which had been fcarlet from thole which 
 were white. 
 
 After all the common procefles of dying 
 with Cochineal, there is found at the bot- 
 tom of the vefiels a confiderable quantity of 
 a deep brown-coloured fediment. This is 
 found, when folution of Tin has been ufed 
 in the dye, to contain a calx of Tin, front 
 which the Tin may be recovered, though 
 fomewhat difficultly, by fufion with inflam- 
 mable fubftances. 
 
 The reft of the fediment appears to con- 
 fift of the impurities of the Tartar, and the 
 grofier parts of the powdered Cochineal. 
 The lighter animal matter being wafhed oft’ 
 with water, dried, ground on a marble with 
 an equal quantity of cryftals of Tartar into 
 an impalpable powder, and then put into 
 water with a little Alum ; a piece of white 
 cloth, boiled in this liquor for three quarters 
 of an hour, acquired a very beautiful crim- 
 fon dye. 
 
 This experiment evinces, that by reduc- 
 ing Cochineal into a powder of moderate 
 finenefs as commonly pradtifed, we do not 
 gain all the advantage, which this valuable 
 commodity is capable of yielding. If the 
 Cochineal, after the ufual pulverization, be 
 mixed with one fourth its weight of pure 
 dry cryftals of Tartar, and the mixture le- 
 vigated into a powder really impalpable ; 
 the faving, in the Cochineal, whether for 
 the crimfon or the fcarlet dye, will be, ac- 
 cording to Mr. Heliot, about one part in 
 four. Though no Tartar is ufually em- 
 ployed in the red or dying liquor, the quan- 
 tity here directed does no injury; it ap- 
 peared on trial, that the colour was rather 
 the more folid for it. In the preparatory li- 
 quor, the quantity of Tartar may be di- 
 miniftied proportionably to that contained in 
 the powder. 
 
 The wild Cochineal or Sylvefter is greatly 
 inferior to the fine fort called limply Cochi- 
 neal : Four parts of the former have no 
 greater efte£I in dying than one ol the lat- 
 t t 2 ter. 
 
 Cochineal. 
 
r w 
 
 C T S. 
 
 508 
 
 ERMES 
 
 - — r 
 
 In.se 
 
 . ter. Nor does the Sylvefter anfwer, in ge- 
 j neral, fowell as the other in regard to the 
 beauty of the colour, particularly for fcarlet. 
 
 VI. K E R M E S. 
 
 f^Frmes grains, fo called, are roundifh 
 ^ bodies about the fize and fhape of a 
 pea, containing under a firm reddilh-brown 
 fkin, a great number of fmall particles of a 
 deeper red colour ; found adhering in the 
 fouthern parts of Europe, to the branches 
 and leaves of the fcarlet Oak, ilex aculeata 
 cocciglandifera C. B- A fmall infeft, lefs 
 than a Millet feed, fixes itfelf upon the tree 
 in the beginning of March, and is by de- 
 grees diftended into this form : The body 
 of the infe£! becomes the hulk or nidus, and 
 the red particles are its eggs. 
 
 The Kermes grains are cured for expor- 
 tation, by drying them on linen cloths ; 
 fome ftrong Vinegar being previoufly 
 fprinkled upon them, to prevent the exclu- 
 fion of the eggs, or kill fuch of the infeds 
 as may be already hatched. In drying, the 
 eggs and young animalcules fall into a red 
 powder, which in fome places, particularly 
 in Spain, is feparated from the hulks by a 
 fieve : The hulks are then formed into balls, 
 and a proportionable quantity of the powder 
 put into the middle of each. 
 
 Frefh Kermes yields upon expreffion a 
 red juice, of a light pleafant fmell, and a 
 bitterilh, roughilh, fomewhat pungent tafte: 
 This, made into a fyrup with Sugar, is 
 brought from the South of France for me- 
 dicinal ufe, and held to be mildly reftrin- 
 gent and corroborant. 
 
 The dry grains impart the fame fmell 
 and tafte, and a deep red colour, both to 
 watery and fpirituous liquors : Both tinc- 
 tures retain their colour on being inlpiiTated' 
 to the confifcence of extracts; nor do they 
 lofe any thing confiderable of their tafte, 
 but the watery lofes all its fmell. 
 
 Woollen cloth, prepared with Alum and 
 Tartar, acquires, on being boiled with dry 
 Kermes berries, a durable deep red colour, 
 called fcarlet- in grain from the Kermes hav- 
 ing been formerly fuppofed to be the grain 
 or feed of the tree, and Venice fcarlet from 
 the greateft quantities having been dyed 
 there. This colour wants the luftre and 
 fire of the Cochineal fcarlet now in vogue, 
 but in return is far more permanent, not 
 
 fubjed to be ftained by dirt or acrid liquors, 
 and when fpotted with greafe may be clean- 
 ed again without injury to the colour. 
 
 Mr. Hellot obferves, that the figured 
 cloths to be feen in the old tapiftries of 
 Bruflels and the other manufactures of Flan- 
 ders, which have fcarce loft any thing of 
 their livelinefs in Handing for two hundred 
 years, were all died with this ingredient: 
 That neverthelefs Kermes is at prefent en- 
 tirely in difufe among the European dyers, 
 though faid to be commonly employed in 
 the Levant, and exported thither from Mar- 
 feilles in conliderable quantities : That when 
 the Ivermes fcarlet (now called an ox-blood 
 colour) is wanted for tapiftries, &c. our 
 dyers endeavour to imitate it with Cochi- 
 neal ; that as the colour is difficultly hit 
 with Cochineal alone, they generally add a 
 portion of Brazil-wood ; and that the dyes 
 thus produced, though at firft more vivid 
 than they ought to be, often lofe their luftre 
 before a year is at an end, and turn white 
 and grey in an extraordinary manner: That 
 Kermes might be again introduced to very 
 good advantage, as its colour is of the moft 
 durable kind, and as fundry Blades are ob- 
 tainable from it with lefs trouble and ex-r 
 pence than from other drugs. 
 
 The fame author has given a great num- 
 ber of experiments upon Kermes, with dif- 
 ferent Saks and metallic Elutions. The 
 principal of thefe are as follows. 
 
 On adding to decodion of Kermes a 
 fmall quantity of folution of Tin, the dark 
 colour of the liquor is immediately bright- 
 ened, and prepared woollen dyed therein in- 
 clines more to the orange than with the 
 Kermes alone. With this improvement of 
 the colour, it receives the imperfedions, 
 though not all the beautv of the Cochineal 
 fcarlet ; all aicalefcent fubftances ftaining 
 the doth, that is deftroying the eflFed of the 
 acid Elution. 
 
 Kermes with Creme of Tartar and as 
 much of the folution of Tin as is employed 
 for the Cochineal fcarlet, (without any 
 Alum,) dyed unprepared cloth of an ex- 
 tremely vivid Cinnamon colour. " On dip- 
 ping the cloth in a Elution of Alum, a part 
 of the red reappeared, but was not beau- 
 tiful. 
 
 With Creme of Tartar, folution of Tin, 
 and Alum in larger quantity than the Tar- 
 tar, this drug gives purplilh colours, which 
 
 vary 
 
C T S. 
 
 I N S F, 
 
 5 ° 9 
 
 vary according to the proportions of the in- 
 gredients. 
 
 If vitriolated Tartar be fubflituted to the 
 Alum and Tartar ; and if after the Kermes 
 has been boiled in a folution of a fmall 
 quantity of this Sait, the Huff be boiled in 
 this mixture for about an hour, the dye 
 proves a beautiful kind of grey, in which the 
 red is little perceived. 
 
 Glaubers Salt employed along with Ker- 
 mes entirely deflroys its rednefs, and gives 
 an earthy grey colour. This dye is very 
 perifhuble, on account of the particular na- 
 ture of the faline fubflance by means of 
 which the tinging particles are applied ; for 
 Glaubers Salt diffolves eafily in cold water, 
 and falls into a powder in the fun’s heat. 
 This obtains equally in all dyes ; thofe 
 drugs which afford moll durable colours 
 with Tartar and vitriolated Tartar, give 
 very perifhable ones with the more diffo- 
 luble and calcinable Salts. 
 
 Green and blue Vitriol, fubflituted fepa- 
 rately to Alum, but taken in conjunction 
 with Creme of Tartar, deflroy likewife, or 
 conceal the red colour of Kermes, which in 
 thefe two experiments has the fame effedl 
 with Galls, for it precipitates the Iron of 
 the green Vitriol which tinges the cloth of a 
 bright grey, and the Copper of the blue 
 which gives a kind of olive dye. It like- 
 wife gave an olive dye with folution of Cop- 
 per made in Aqua fortis ; a certain mark, 
 that it poffeffes, like Galls, an aflringent 
 precipitating quality. It is probably the 
 aflringency of Kermes that renders its dye 
 fo durable ; for all the barks, woods, roots 
 and other fuhftanees that are aflringent, 
 yield permanent colours. 
 
 White Vitriol, employed with cryflals of 
 Tartar, changes the red colour of Kermes 
 into a violet. A tinCture of Bifmuth-ore 
 in Spirit of Nitre, and a folution ofBifmuth 
 itfelf made leifurely in four times its weight 
 of Spirit of Nitre diluted with an equal 
 quantity of water, gave alfo a violet dye 
 upon white cloth. 
 
 VII. COCCUS POLONICUS. 
 
 <oOccus Polonicus is the egg of an infeft, 
 ^ about the fize of a Coriander feed, of a 
 purple-brown colour on the outfide and full 
 of a blood-red juice ; found adhering to the 
 upper part of the roots of a fpecies of Knot- 
 
 grafs called Polygonum coccferum , Pofonian 
 knawel. It is met with in great abundance 
 in walle fandy grounds in different parts of 
 Poland, particularly in the Ukrain. 
 
 According to Bernhardus a Bernitz (in 
 the Ephemerules natures curioforum. dec. i . an. 
 3.) the peafants take up the plant about 
 midfummer, by means of a final! concave 
 fpade or dibble, and having picked off the 
 berries as they are called, replace it in the 
 ground, with furprizing celerity and ad- 
 drefs. The Coccus, cleaned from the earth 
 by lifting, is dried in a warm room or by 
 the fun’s heat ; fome Vinegar or very cold 
 water be 
 
 Co 
 
 ecus. 
 
 emg fprinkled on, 
 
 to 
 
 — prevent the 
 
 exclufion of the in feels. Sometimes the 
 
 red matter is feparated from the (kins and 
 formed into balls by gentle preffure, fo as 
 not to fired or wafle the colouring juice. 
 
 The fame author relates, that the Turks 
 and Armenians, who purchafe the Coccus 
 from the Jews in Germany, employ it for 
 flaining wool, hair, leather, and the manes 
 and taiis of their horfes, red : That the 
 
 juice mixed and extracted with Citron or 
 Pomegranate-juice, or with Wine, is in 
 daily ufe among theTurkifh ladies, for 
 flaining the ends of their fingers and toes : 
 That formerly the Dutch dyers mixed their 
 Cochineal with one half of Coccus Polo- 
 nicus both for fcarlets and for crimfons : 
 That a tincture of the Coccus extracted 
 with Citron-juice, or a certain Lixivium, 
 with Alum and a little Gum arable, was 
 ufed by the painters, particularly inRuffia : 
 That with whiting it yields a crimfon lake 
 equal to that prepared from Cochineal or 
 fcarlet cloth : That he faw an excellent 
 Carmine made from it by a particular per- 
 fon at Paris, which was fold for three 
 guineas ( tribus aureis ) a dram : And that the 
 red Spanifh paper and wool, fo much in ufe 
 at the toilettes of the French and Spanifh: 
 ladies', receive their colour from the juice of 
 this drum 
 
 The trade in this commodity has never- 
 thelefs been for a long time very inconfl- 
 derable : Among us, the Coccus is at pre- 
 fent fcarcely otherwife known than by name. 
 Mr. Plellot informs us, that having pro- 
 cured fome from Dantzick, for trial as a 
 dying drug, it came dearer than Cochineal, 
 as it did not afford one fifth fo much colour 
 as that American infedl does ; and that he 
 never could by any means obtain from it a 
 
 fcarlet 
 
5 10 
 
 Coccus. 
 
 I N S E 
 
 fcarlet dye, nor any other than Mas, flefh- 
 colours and crimfons, more or lefs lively. 
 Mr. Marggraf obferves, in the Berlin Me- 
 moirs, that this infedt contains, like Ants, 
 an expreffible Oil ; that this principle is the 
 caule of the failure of thofe who have em- 
 ployed it in dying ; and that means may be 
 found of preventing the ill effects of the 
 oily matter. For rny own part, I have had 
 no experience of it. 
 
 VIII. PURPLE FISH. 
 
 ^TpPIE precious Tyrian purple of the an- 
 -*■ cients was procured from a fhell-fifh of 
 the Buccinutn or Whilk kind : A fmall vein 
 found in the body of the animal, though 
 colourlefs itfelf, communicated the admired 
 dye. 
 
 Towards the end of the laft century, the 
 fame fort of fifh was difcovered in plenty on 
 fome of the fhores of Ireland, on thofe of 
 Somerfetfhire, and the oppofite ones of 
 South Wales ; and fome perfons made con- 
 fiderable profit by marking linen with its 
 juice, of a fine durable crimfon colour. 
 
 The fhell, which is confiderably hard, 
 is broke by a fmart blow, with care not to 
 crufh the body of the fifh within. After 
 picking off the broken pieces, there appears 
 a white vein or refervoir, lying tranfverfely 
 in a little furrow near the head. This be- 
 ing carefully taken out, and characters 
 drawn with it, or its vifcid juice fqueezed, 
 upon linen or filk, the part acquires imme- 
 diately on being expofed to the fun, a pale 
 yellowifh-green, which quickly deepens into 
 an emerald green, then changes to a blue, 
 and at laft to a finepurplifh red. If the cloth 
 be now wafhed with fcalding water and 
 Sope, and laid again in the fun, the colour 
 changes to a beautiful crimfon, which buf- 
 fers no further alteration from fun or air, 
 cr Sope, or Alum, cr a’caline Leys, or any 
 
 C T S. 
 
 of the fubftances ufed for efiaying the per- 
 manency of colours. 
 
 The juice of the Purple Fifh receives no 
 colour itfelf, and communicates none to 
 filk or linen, without expofure to the fun. 
 It feems to be the light, and not the heat 
 of the fun, that calls forth the tindture ; for 
 when the cloth is covered with thin opake 
 bodies, which tranfmit heat without light, 
 no colour is produced, while tranlparent 
 ones give no impediment to its production. 
 The juice itfelf, in clofe glafs vefiels, be- 
 comes prefently purple in the fun. The 
 light of culinary fire, concentrated by con- 
 vex glaffes and concave mirrors, has no ef- 
 fedt. The fucceffion of colours is beft ob- 
 ferved when the fun is low and his adtion 
 weak ; at noon in fummer they are io 
 quick as not to be eafily diftinguifhed. See 
 the Philofophical Tran factions, N° 178, 
 and the Memoirs of the French Academy 
 for the year 1 736, and 1 7 1 r . 
 
 Mr. Reaumur informs us, in the Memoirs 
 for the year laft mentioned, that on fome 
 of the French coafts he found great num- 
 bers of fmall elliptical ipheroidal bodies ad- 
 hering to the rocks by a fhort fern like 
 fruits, and that the purple fifties were com- 
 monly accumulated plentifully about thefe. 
 On examining thefe bodies, he found them 
 to be vehicles filled with a liquid of the fame 
 quality with thejuiceof the fifh, but lefs vifcid, 
 and of confequence more readily fpreading 
 upon the linen. He fufpedts them to be the 
 eggs of fome fea fifh, perhaps of the Purple 
 Fifh itfelf, though he never could obferve any 
 thing like them on difiedting that fifh, nor 
 any animal produced from the vehicles. He 
 fays they are in perfection only in autumn ; 
 and that when any are met with in fummer, 
 they have either loft their colouring juice, 
 or the juice has’ loft its power of becoming 
 purple in the fun. 
 
 SECT. 
 
C 5 11 ] 
 
 SECT. IV. 
 
 \ 
 
 Horny Parts of Animals, 
 
 B Y horny parts we underhand thofe, which are dry and hard, in fome de- Horns. 
 degree flexible, very confiderably fo when heated, and fo cohefive as i_ - v j 
 not to be at all pulverable in a mortar ; whether produced upon the fore- 
 head, or on the feet of animals. The general name of the clafs might be taken 
 indeed with greater propriety from the productions of the feet; for the hoofs 
 and claws and nails ol all animals are of this kind, but fome horns are not. 
 
 The horns of the Rhinoceros and the Ox are of the truly horny kind, but 
 thofe of Hart are of the bony. 
 
 THE Rhinoceros is fo called from fiv a nofe, and xspxs a horn ; the horn I. 
 or horns being placed, not where thofe of other animals are, but immediately Rhinoceros’s 
 above the nofe, betwixt the eyes. The Rhinoceros is a very large, fierce qua- , HoRN - t 
 druped of prey ; an inhabitant of woods and defarts in different parts of Afia 
 and Africa. He has very little hair, but the Akin is remarkably tough and 
 ftrong, above half an inch thick, and full of wrinkles, fo as to look, when he 
 moves, like fcales. He is fwift of foot, though the legs are fhort ; and of an 
 extraordinary quick fcent : The fight is weak, and the eyes deep ; fo that he can- 
 not fee fidewife, nor turn quick. The figures of this animal, given by natural 
 hiltorians differ from one another : The fkin, preferved in the Mulasum of the 
 Royal Society of London, comes the nearefl to thofe of Bontius and Pifo. 
 
 This animal has been generally iuppofed to have only one horn, but ap- 
 pears to have often two, a large and a fmali one ; of which there are fpecimens 
 in many collections in Europe, particularly in that of his Daniih majefty. 
 
 The horn is at firft white ; by age it grows grey, and at length blackifh on the 
 outfide, its internal whitenefs continuing : Its length is from a quarter of 
 an ell to an ell, according to the age of the animal: It is always fome- 
 what crooked, remarkably thick at the bottom, and not equably taper or of 
 a regular pyramidal figure, but drawn in fiender a good way below the tip : 
 
 It is folid throughout, except a little hollownefs at the bafis, where it is alfo 
 externally rough, chapt, full of fmali holes, and befet with fliff hairs, of 
 which in the horns brought to us, only the roots generally remain : The upper 
 partis fmooth. Its texture is very compaCt; and in thin pieces it has fome 
 degree of tranfparency. It is ufed for fundry mechanic purpofes, as for mak- 
 ing fword-hilts, knife-handles, cane-heads, fnuff-boxes and other toys. It 
 was formerly of great efteem for drinking vefiels, from an idle notion of its 
 refilling poifon. 
 
 Half an ounce of Rhinoceros’s horn, finely rafped, gave with rectified Spirit 
 of Wine only four grains of extraCl, which had a rancid take, without any 
 i fmell : 
 
Horny Substances. 
 
 Rhinoceros’s f me u . The remaining horn looked reddifh. The lame quantity, boiled 
 t ° RS ' , ftrongly with water, yielded two fcruples of gelatinous extract, of a brown 
 colour, and fomewhat faline tafce : The refiduum was grey. The mineral 
 
 acid fpirits, and cauflic alcaline Lixivia, almoft totally diflblve it : Thefolu- 
 tions made in the nitrous and vitriolic acids are yellow ; in the marine, colour- 
 lefs. Weaker faline menftrua, as Oil of Tartar per deliquium, Spirit of Sal 
 ammoniac, and the vegetable acids, have no effedt on it. We may judge 
 from hence, that this horn can have no great claim to any medicinal virtue, as 
 it is not diffoluble in the fluids of animal bodies. 
 
 Two ounces of the rafpea horns, diftil led in a retort with an open fire, yielded 
 half an ounce and a fcruple of urinous liquor, two drams of fetid Oil, and 
 three drams and a fcruple of volatile alcaline Salt : The Caput mortuum, 
 which weighed fix drams, afforded a fmall portion of fixed lixivial Salt. The 
 phlegm which arofe at firft, amounting to about two drams and a fcruple, was 
 confiderably fetid, and had fomewhat of a volatile imel!. 
 
 There are fome other animals which have received the name of Rhinoceros, 
 from their being furnifhed with a horn fituated nearly in the fame manner. One 
 is the fcarabrfus cornutus or horned chafer, found about tan-pits and where lea- 
 ther is buried in the ground. Another is the Rhinoceros bird, or horned 
 Indian Crow: Its beak, and the upper part of the horn, is red like mi- 
 nium, the middle yellow, and the margin {freaked with black : An entire 
 
 head is preferved in the Mu feu m of the Royal Society. Willoughby and 
 others mention alio an Indian horned fifh. 
 
 II T HE horns of Oxen and Cows are Iefs compact than thofe of the Rhino- 
 
 Qx-horn. ceros > hut more tranfparent. They are ufed for tobacco and fnuff- boxes, for 
 
 powder-horns, the horns of lanthorns, imitations of tortoifefliell, TV. as alfo 
 for hardening Iron by cementation, TV. 
 
 Half an ounce of thefe horns, digefted with rectified Spirit of Wine, gave 
 five grains of extract, or one grain more than I had obtained from an equal 
 quantity of the Rhinoceros’s horn. Boiled in water, they yielded lefs extract 
 than the horn of that animal; only five and twenty grains being obtained from 
 half an ounce, whillt the fame quantity of the other gave forty grains. The 
 watery extract was of a yellowifh-brown colour and lahne tafte, and the refi- 
 duum grey : The fpirituous extradt was the fame with that of the Rhinoceros’s 
 horn, but the remainder had acquired no rednefs or change of colour. 
 
 Spirit of Nitre difiblves thefe horns totally. Spirit of Salt diffolves them 
 only in part •, the folution is of a reddifh-yellow colour. Spirit of Vitriol alia 
 only partially diffolves and corrodes them, acquiring a flight yellow tinge. 
 Spirit of Sal ammoniac and Oil of Tartar extract exceeding little : The li- 
 
 quors, however, become yellowifh, and the horn brown. Cauflic alcaline 
 Lixivia totally dificlve the horn into a yellow liquor. 
 
 Sixteen ounces of Cows-horn, cli {billed in an open fire, gave over in all 
 nine ounces and a half of mixed matter : Of volatile Salt I had two ounces 
 three drams ; of urinous fpirit five ounces and a half-, and of empyreumatic 
 Oil one ounce five drams the Caput mortuum weighed five ounces and a half ; 
 and in calcination to whitenefs loft an ounce : From the white calx I extracted, 
 by elixation with water, fix grains of a fixed faline matter. In 
 
Horny Substances, 513 
 
 In another diftillation of Cow’s-horn, I obtained, from two ounces of the Ox-horn. 
 horn, half an ounce and half a dram of urinous liquor, a dram and a half of 
 fetid Oil, and three drams and a half of volatile Salt (x ) : The Caput mortuum 
 weighed fix drams and a half, which probably would not have yielded a Tingle 
 gram of fixed Salt, as in the foregoing experiment I had obtained but fix 
 grains of that Salt from fixteen ounces of the horns. 
 
 THE beautiful fhell of the Tortoise belongs alfo to this clafs. The III. 
 Tortoife is an oviparous four-footed animal, whofe body is inclofed in ewoTortoise- 
 Thelis joined together along the Tides, into which it can likewife occafionaliy shell. 
 draw in both the feet and the head : The upper fhell is convex, the lower fiat. 
 
 There are many different kinds of Tortoifes in America and the Eaft-Indies, 
 fome living almoft wholly on the land, others almofc wholly in waterq and 
 others equally in both fome of an oval and others of an angular figure y of 
 various colours on the upper fhell, as yellow, black, brown, white, purple, 
 greenifh, with different clouds and variegations ; fome fmall, weighing a few 
 pounds, and others of enormous fizes. 
 
 The upper fhell of the Tortoife is compofed of two diffimilar fubftances : 
 
 That which immediately inverts the back of the animal is of the bony kind, 
 and almort as hard as rtone : The outer lamina is horny, flexible, here and 
 there tranfparent. It is oniy this laft that is called Tortoife- fuel 1, and in which 
 the beautiful colours and variegations refide. The horny fhell conflfts of feve- 
 ral pieces, whofe Teams and junctures with one another, and with the bony 
 part underneath, are fufficiently diftinguifhable. The workmen fplit them 
 afunder by certain inftruments, and employ the elegant horn for a variety of 
 toys and utenflls, combs, fword-hilts, clock-cafes, boxes, coverings for mufi- 
 cai inftruments, perfpe&ive-glaflfes, ific. &c. I have often been iurprized at 
 their dexterity in working and polifhing this fhell, but particularly at the neat 
 manner in which they unite two pieces together, the union being fo curioufly 
 performed, that it is fcarce poflible to diftinguifh the junhlure. They have 
 likewife methods of embellifhing it with fundry beautiful colours, befides thofe 
 which it receives from nature (y). 
 
 Half 
 
 (x) Volatile Salt. ] The proportion of vola- 
 tile Salt in thefe two experiments is confi- 
 derably different, being in one two ounces 
 three drams , and in the other three ounces four 
 drams, from fixteen ounces of the horn. 
 Whether this has happened through any 
 miftake, or from different pieces of horn 
 affording quantities of Salt really fo diffe- 
 rent, or from more of the Salt having been 
 diffolved by the fpirit in one experiment than 
 in the other, I cannot determine. Per- 
 haps, as the two analyfes appear to have 
 been made at diftant times, and with fome- 
 what different views ; in the former the pu- 
 rified Salt , and in the latter the rough Salt 
 may be meant. 
 
 U 
 
 (y) TVorking and joining of Tortoife -Jh ell. 
 Tortoife-fhell and horn become foft in a 
 moderate heat, as that of boiling water, fo 
 as to be preffed, in a mould, into any form, 
 the fhell or horn being previoufly cut into 
 plates of a proper fize. 
 
 Plumier informs us, in his Art de tourner, 
 that two plates are likewife united into one 
 by heating and preffing them ; the edges 
 being thoroughly cleaned, and made to fit 
 clofe to one another. The Tortoife-fheli 
 is conveniently heated for this purpofe by 
 applying a hot iron above and beneath the 
 jundfure, with the interpofkion of a wet 
 cloth to prevent the fhell from being fcorch- 
 ed by the irons : Thele irons fhoultf be 
 u u pretty 
 
5 / 4 H o r n y Substances. 
 
 Tortoise- Half an ounce of Tortoife-kiell, digeked with Spirit of Wine, yielded four 
 shell. ^ grains of extract, which knelt like the newly diddled water of Cow -dung {Aqua 
 * omnium fiorum) and tailed fornewhat 1'aline. Another half ounce, boiled in 
 water, gave fifteen grains of ex trad, of a brown colour and faline take. The 
 fuel] remaining after the action of both menkrua, was in appearance un- 
 changed. 
 
 Spirit of Vitriol diffolves greatcfl part of it into a reddifh-brown liquor: Spi- 
 rit of Nitre and Spiritof Salt diffolve the whole ; both thefe folutionsare fome- 
 what yellowifh. Spirit of Sal ammoniac corrodes it a little, but receives no 
 colour. Fixt alcaline Lixivia likewile corrode a little of the fhell, and acquire 
 a yellowifh tinge : Cauftic alcalies corrode more of it, and become yellower. 
 
 Two ounces of Tortoife- fhell, diitilled in an open lire, yielded a dram and 
 a half of phlegm, of an urinous fmell ; a dram and a half of a pretty fetid 
 urinous fpirit ; half an ounce oi empyreumatic Oil, which knelt likewile very 
 volatile, but lefs fetid than the fpirit ; and three drams and a half of volacile 
 Salt extremely fetid. The Caput mortuum weighed five drams and a half. 
 
 IV, AS the hoof of the Elk has been celebrated for fome extraordinary quali- 
 Elks-hoof. ties, it was thought proper to examine it chemically, and compare it with that 
 U- — — •> of the ox. 
 
 The Elk is a wild quadruped, of the Stag kind, but fornewhat larger* ex- 
 tremely fearful of men, an inhabitant of woods in the cold countries, as Poland, 
 Ruffia, Lithuania, Couriand, Sweden, Norway, Rulka, &c. It is a great 
 rarity if any of them krays into Silelia, Pomerania, Hungary or our neigh- 
 bourhood [Berlin.] Moil of us however have feen the animal, as his majeky 
 has often had young ones brought from Pruffia. The male fheds his horns 
 annually like the common Stag, but the female has no horns. The fiefh is 
 laid to be equal to venifon. 
 
 The fkin of this animal is one of the thickek, krongek, and finek kind of 
 leather in the world. The bones are faid to be not inferior to ivory, and to have 
 one advantage above it, that they are not fo apt to turn yellow. The hoof is 
 made into boxes, bracelets, rings and other toys. 
 
 The hoof of the Elk is commonly fornewhat longer and larger than that of 
 the Stag, of a black colour on the outfide and whitiki within. The outer pare 
 is very compsdfc, firm and horny; the inner white part is tranfparent; and 
 within this is another whitifh fubkance. On each foot there are two large clo- 
 ven hoofs, and above thefe two imaller ones. 
 
 It is faid that the Elk is fubjedt to epileptic fits ; and that he effectually cures 
 them by fcratching behind his right ear with his left hinder hoof, or behind his 
 left ear with the hinder hoof of the right fide; for the hoof of the fame fide, 
 or the hoof of the fore foot will not do : From lienee ElkVhoof has been ce- 
 lebrated as a fpecific in epilepfies, being taken internally, or worn as an amulet, 
 if one could be ferious on fuch a ridiculous occafion, we might afk, how it 
 
 comes 
 
 pretty thick, that they may not lofe their the colouring drugs commonly ufed in dy- 
 foeat before the union is effedted. ing, and by certain metallic folutions. See: 
 
 Both Tortoife-fhell and horns may be the ar tide Bones in the following fe&ion, 
 Drained cf a variety of colours, by means of 
 
Horny Substances. 515 
 
 comes that the Elk fhould ever be troubled with an epilepfy, when he carriesELK’s-HooF. 
 the Amulet conftantly about him: Whether a man will be affedted in the 
 lame manner by fwallowinga piece of the hoof in powder, as the animal was 
 by lcratching himfelf with it : Whether it is anywife poflible for the Elk to get 
 his hinder hoof up to his ears; and if it was, whether the fcratching might not 
 be more rationally attributed to another caufe. According to fome accounts, 
 a kind of flinging fly attacks and lodges in his head, and occafions fuch un- 
 eafinefs, as might very well warrant his fcratching himfelf, without any thing 
 epileptic in the cafe. 
 
 Half an ounce of rafped Eik’s-hoof, digefled with rectified Spirit of Wine, 
 gave fix grains of extradl, which had no remarkable fmell or tafle : The refi- 
 duum looked reddifh. Water extracted from the fame quantity two fcruples : 
 
 The infpiffated extradl had a faline tafle, but no fmell : The refiduum looked 
 
 greenifh. 
 
 Spirit of Vitriol partly diffolved and partly corroded it: Of the corroded 
 matter, partfwum on the furface, and part funk to the bottom: The folution 
 
 was reddifh- brown. Spirit of Nitre totally diffolved it into a Citron yellow li- 
 quor. Spirit of Salt partly diffolved and partly corroded it, and acquired a 
 richer yellow tindlure. Spirit of Sal ammoniac had no effedt: Solution of fixt 
 Alcali extradled a flight yellowifh tinge : Solution of cauflic Alcaii totally dif- 
 folved it, and became likewife yellowifh. 
 
 On diddling two ounces of Elk’s- hoof in an open fire, I obtained fird two 
 drams of a phlegmatic liquor which lmelt like Sope ; afterwards a dram and a 
 half of a dinking fpirit, three drams of empyreumatic Oil, and half an ounce of 
 volatile Salt. The Caput mortuum weighed five drams and a half. 
 
 T El E hoofs of Oxen and Cows differ very iittle from that of the Elk, and V. 
 have commonly been fubdituted to it in the fhops. It is faid that Ox’s-hoofOx-HOOF. 
 ilinks in rafping, whild that of the Elk emits an agreeable fmell. On trial, 
 the fmell of both was found to be difagreeable : That of the Cow’s-hoof was 
 mod fo, not however from any peculiar quality of the hoof itfelf, but from the 
 dung and urine in which this kind of cattle fo often dands. When the hoofs of 
 Cows or Oxen are thoroughly cleaned, their fmell does not prove remarkably 
 different from that of the Elk’s. 
 
 From half an ounce of rafped Ox’s-hoof I obtained fix grains of fpirituous ; 
 and from the fame quantity, half a dram of watery extract. The refidua were 
 of the fame colour as thole of the Elk’s-hoof ; but there was this difference in 
 the fpirituous extract, that it fmelt and taded a little like Cow-dung. Spirit of 
 Vitriol partly diffolved and partly corroded Ox’s-hoof, in the fame manner as 
 the Elks, but the folution was more of a brownifh colour. Spirit of Nitre 
 diffolved this equally with the other: The folution had lefs of the Citron hue. 
 
 Spirit of Salt, which partially diffolved the Elk’s, almod totally diffolved the 
 Ox’s-hoof into an orange-yellow liquor. Spirit of Sal ammoniac, and folution 
 of fixed alcaline Salt, extradled a flight yellowifh tinge : Solution of cauflic 
 Alcali almod totally diffolved it into a yellowifh. liquor. 
 
 Two ounces of rafped Ox-hoof, diddled in an open fire, gave over four 
 drams and a half of urinous fpirit, which fmelt fomewhat like A fa ietida ; one 
 
 U u u 2 dram 
 
516 Bony Substances. 
 
 Ox-hoof, dram and a half of empyreumatic Oil •, and half an ounce of volatile Salt r 
 The Caput mortuum weighed fix drams. The Oil and Salt had the ufual em- 
 pyreumatic fmell. 
 
 In another diftillation of Ox-hoof, I obtained from fixteen ounces of the 
 hoof, feven ounces fix drams of urinous fpirit, one ounce two drams of volatile 
 Salt, and two ounces of empyreumatic Oil. The Caput mortuum weighed 
 three ounces, and was reduced by calcination to two ounces two drams, which 
 yielded on elixation with water twelve grains of a fixed faline matter. 
 
 VI. THE flexible horny fubftance, called Whale-bone, arms the gums of 
 Whale- the common Whale, in the room of teeth. In the mouth of one WhaJe there 
 eone. are five hundred pieces of this bone, fome of which are five or fix ells in 
 
 Two ounces of Whale-bone, boiled with water, yielded four fcruples of ex- 
 tract-, arid afterwards with rectified lpirit, half a dram : On inverting the order 
 of applying the two menftrua, I got from the fame quantity, one dram and 
 four grains of fpirituous, and afterwards a dram of watery extract. The indif- 
 foluble part weighed in the firft cafe one ounce fix drams eight grains, in the 
 latter one ounce fix drams thirty grains. 
 
 On diddling fixteen ounces of Whale-bone in an open fire, there arofe five 
 ounces of urinous lpirit, two ounces of empyreumatic Oil, and a volatile Salt, 
 which when rectified weighed ten drams. The Caput mortuum weighed five 
 ounces, and on being burnt in open veffels to whitenefs loft juft one half : From 
 the allies were extracted, by means of water, fifteen grains of faline matter. 
 
 SECT. V. 
 
 Bony Parts of Animals. 
 
 B .ON Y fubftanc.es are the hardeft and firmed: of all the parts of animals ; 
 more or lefs brittle ; either not at all, or in a very fmall degree flexible, 
 and not capable of being foftened by heat like horn, fo as to receive 
 figures or impreftions. Under this head are comprehended not only bones 
 ftrictly fo called, but fome kinds of horns and other animal productions : The 
 horns of the Hart and the Elk are, chemically confidcred, of the bony kind, 
 whilftthe bones of many forts of fifties, particularly of fmall ones, are horny or 
 cartilaginous. 
 
 Clean found bones are white, and of a clofe compact texture : Such as are 
 difeafed, look yellow, brownifh or blackifh, and porous or corroded : I have 
 feen, in England, the fkeleton of a perfon who died in the laft ftage of the ve- 
 nereal difeafe, whofe bones were all carious and corroded, not a Angle one in 
 the whole body being found. It is matter of common obfervation, that Sugar, 
 
 too 
 
Bony Substances. 517 
 
 too hot and too cold liquors, fmoking Tobacco, &c. make the teeth yellow, Bones. 
 black, and carious. Two procefies are delcribed in the Act a Hoffnienfia for v # 
 whitening bones : Frofeffor Rau had a method of giving them a great degree Whitened, 
 of whitenefs. By bareexpofure to the air, fun, and rain, for a length of time, 
 they become notably white ; but the whited: bones, kept in rooms tainted with 
 fmoke or fuliginous vapours, grow in a little time yellowifh, brownifh, and 
 unfightly. It is cuftomary for the purification of bones, to boil them in alca- 
 line liquors; which by difTolving and extrading the fuperfluous fat, improve 
 their whitenefs. 
 
 Boerhaave obferves, that alcaline Salts render bones harder and firmer; and Hardened 
 that acids make them fofter and more flexible (2). Thefe effeds fucceed in anc * 
 certain circum dances, but not univerfally ; for bones may be hardened and 
 foftened both by acids and by alcalies, according to the quantity of the faline 
 matter employed, and the manner in which it is applied. 1 have made bones 
 harder and more comp-ad, by treating them with the ftrongeft of the mineral 
 acids ; though, when the acid is in fufficient proportion, it deflroys or diflolves 
 them. In Papin’s digeftor (a ftrongclofe vefiel, in which the fleam of boiling 
 liquors is confined, and rhe fluid by this means made to undergo a greater de- 
 gree of heat than it could otherwife fuftain,) the hardeft bones are reduced, in 
 a fhort time, by the adion of Ample v/ater, into a fuft pap or gelly ; and alca- 
 line liquors produce this effed frill fooner. 
 
 In open vefifels, entire bones are difficultly, if at all, to be boiled foft by wa- 
 ter; but fuch as are rafped, or otherwife reduced into Anal! parts, give out to 
 that menftruum greatefl fhare of their oily, gelatinous and faline matter. What Calcined., 
 remains is almofl a mere alcaline earth : Urged with an open fire, it difcovers 
 but a flight fetid fine!! ; and in mixture with Nitre, it occafions very little de- 
 flagration. Rafped bones in fubftance, mixed with Nitre and injeded into a 
 red-hot crucible, deflagrate flrongly, and are very quickly calcined and re- 
 duced into a pure white earth. 
 
 Large entire bones are difficultly calcined to whitenefs throughout, a part 
 in the middle remaining black and coaly, unlefs the fire is very flrong and long 
 
 continued. 
 
 (z) Bones foftened by acids.'] In the hiftory 
 of the French Academy for the years 1742 
 and 1743, there is an account that Mr. 
 Geoffroy produced before the Academy a 
 fmall ivory fpoon, which by lying long in 
 Muftard was become flexible and transpa- 
 rent like horn : That Mr. Fouchy faw an 
 ivory fpoon, which by lying for a conlider- 
 able time in Milk was become fupple like 
 Leather ; and that Mr. Hunauld produced 
 bones which had been foftened by keeping 
 in Vinegar, afterwards hardened to their 
 natural ftate by keeping in water, and foft- 
 ened a fecond time by Vinegar. 
 
 I have obferved that the nitrous and ma- 
 rine acids diluted, and the acetous acid, 
 make bones flexible and tough like leather ; 
 but that the diluted vitriolic acid, though it 
 
 renders them notably foft, makes them at 
 the fame time brittle. It feems as if great 
 part of the earthy matter, which is the bafis. 
 of the bone and on which its hardnefs de- 
 pends, was dikolved and extracted by the 
 three firk, whilk the latter, incapable of 
 difTolving this kind of earth into a liquid 
 form, only corrodes it into a kind of fele- 
 nitic concrete (See page 494.) which re- 
 mains intermixed in minute particles among 
 the gelatinous matter. 
 
 I have not found that the foftened bones,, 
 whatever acid they were foftened by, reco- 
 vered their hardnefs by keeping in -water.. 
 Slips of foftened Ivory, after lying above a 
 month in water, continued nearly as foft as 
 when they were taken- out of the acid li- 
 quor. 
 
518 Bony Substances. 
 
 Bones, continued. It is obfcrvable, that Ample calcination does not reduce bones, as 
 «v—— it does vegetable Jubilances, to allies ; the bone (till retains its original figure, 
 but becomes brittle and crumbly. Boerhaave reports, that bones thus rendered 
 brittle recover their priftine hardnefs on being foaked in water ; but on trial, 
 this did not happen : And indeed I could not expedl that it fhould happen, as 
 the bone loles in calcination its conglutinating, oily, and faline parts, which 
 Ample water cannot pofiibly reftore to it. 
 
 Their ufes. Bones are a very ufeful article, not only for making different kinds of toys, 
 but likewife in feveral of the chemical arts ; as for making caff Iron malleable 
 (See page 76.)-, for abforbing the Sulphur of fulphureous ores ; for forming 
 tefts and cupels, or vefifels for refining Gold and Silver with Lead, burnt bones 
 compofing a mafs of a porous texture, which abforbs the vitrified Lead and 
 other metals, whilft the unvitrefcible Gold and Silver remain entire behind; 
 for the preparation of milky glafifes and porcelanes ; for the rectification of vo- 
 latile Salts, and empyreumatic Oils ; and for making Glue. The bones of 
 different animals are not equally fit for different ufes : Even the Glue or gela- 
 tinous part of the bones of one animal is notably different, both in quantity 
 and cohefivenefs, from that of another, as we fhall fee hereafter. 
 
 Artificial We often find in the earth petrified bones, greateft part of their gelatinous 
 
 Turcois. matter being extraCled by the moifture, and a ftony one introduced in its 
 room. In fome parts of France, petrified bones are met with, which have an 
 impregnation of Copper : Hence on being calcined a little in an open fire, a 
 volatile Salt is produced from the remains of their gelatinous principle, and 
 the bone is tinged throughout of a fine greenifh-blue colour, Copper always 
 Irriking a blue with volatile alcalies. The French Turquoile ftones are no 
 other than thefe bones prepared by calcination : They are very durable, and 
 
 bear to be worked and polifhed nearly in the fame manner as Glais ; without 
 the imperfection, infeparable from glafiy bodies, of being brittle {a). 
 
 We 
 
 as Cryftal, and that they have a peculiar 
 imperfection of changing, on being long 
 kept, to various {hades of green, whilft the 
 colours of other precious ftones are unalter- 
 able: That the methods directed by authors 
 for reftoring their beauty do not perfectly 
 fucceed ; a Perfian Furcois, which had be- 
 come green, being fteeped in Aqua fords 
 for twenty-four hours, the green colour dif- 
 appeared indeed, but the blue which the 
 {tone acquired was fo faint thac it was not 
 of more value than when it was green : And 
 that the French Turcois is totally diftolved 
 by Aqua fortis, and gives out its colour to 
 diftilled Vinegar .... This diftolubility of 
 the French Turcoifes in acids which have 
 no aCtion on the oriental, thews that the 
 bafts of the one is a different kind of earth 
 from that of the other, and affords a ready 
 method of diftinguiftftng the two.. 
 
 Colouring 
 
 (a) French Turco'jes .] Mr. de Reaumur 
 has given a paper on this fubjeCt in the Me- 
 moirs of the French Academy for the year 
 1715. He informs us that the mines which 
 afford Turcoifes are chiefly in the lower 
 Languedoc, near the village Simore : That 
 the ftones, as taken out of the mine, re- 
 femble different bones, teeth, LV. of vari- 
 ous ftzes, and are in colour whitifh, grey, 
 or yellowifh, like the ftones commonly ufed 
 in building : That they receive their blue 
 colour on being flowly heated to ignition ; 
 and that if the fire is continued after they 
 have acquired the colour, they lofe it irre- 
 coverably : That the colour, when in per- 
 fedfion, is an opakeblue, inclining to green, 
 but without any fenftble admixture of that 
 colour; and that he has fe'en fome of them 
 equal in hardnefs as well as colour to thofe 
 of Perfta : That the beft are fcarcely fo hard 
 
Bony Substances. q 19 
 
 We fhall now prcKeed to examine, more particularly, the bony fubftances of Bones. 
 different animals. And here it may be proper to obferve, that as a thorough 
 knowledge of the chemical ftrudture and principles ol the different Jubilances 
 ranked together in one general divifion, as horns or bones, can be obtained 
 only from an a&ual examination of a number of the particular fubftances be- 
 longing to each divifion-, I have chofen, tor the fubjeCts of this examination^ 
 thole lubflances to which fome confiderable medicinal virtues have been attri- 
 buted, or which are employed for mechanic ules. Thus the experiments an- 
 fwer a double end : At the fame time that they fhew, by particular examples, 
 the chemical conftitution of this or that kind of bodies, they enable us alfo to 
 form iome judgment about the medical ules of the particular bodies.. We fhall 
 find from them, that many of thofe fubftances, to which phyfieians have 
 aferibed great virtues, and on which they have had fome dependence even in 
 calcs of importance, contain fo much of a mere earth, give out fo little to the 
 force of boiling water or fpirit, and this little of lo infignificant qualities, that 
 their virtues may very juftly be queftioned. 
 
 OF the thigh-bone of an Ox, four drams, finely rafped, were thoroughly j 
 boiled in diftilied water . The decoblion, evaporated, lei t four fcruples of a Ox -bone 
 yellowifh extract, which was found to be little other than Sea-falt. Rectified ■_ 
 
 Spirit of Wine, long digefted and boiled upon the rafped bone, extracted from 
 four drams, no more than half a grain. The bone, remaining after the action 
 of water, appeared unchanged in colour; but that which had been boiled in 
 fpirit, looked reddifn. 
 
 The acid fpirits of Vitriol, Nitre and Sea- fair, totally diftblved it: The fo- 
 lution made in the vitriolic acid was yellowifh, and ftiot into fine white cry - 
 ftals-: Thofe made in the nitrous and marine were colourlefs. Alcaline liquors 
 
 had. 
 
 Colouring and hardening of bones.\ Bones 
 and horns may be ftained of a variety of co- 
 lours, by fteeping or boiling them in decoc- 
 tions of the vegetable and animal fubftances 
 by which woollen and filk are dyed. See 
 the refpedtive colouring drugs. 
 
 They are ftained alfo, without heat, by 
 metallic fclutions ; and by means of thefe 
 may be fpotted or variegated at pleafure. 
 Thus folution of Silver in Aqua fortis gives 
 a brown or a black according to its quan- 
 tity ; folution of Gold in Aqua regia or in 
 Spirit of Salt, a fine purple ; folution of 
 Copper in the acetous acid, a fine green ; 
 and folutions of the fame metal in volatile 
 alcalies, a blue, which at firft is deep and 
 beautiful, but changes, upon expofure to the 
 air, into a green or a bluifh-green. If the 
 bone or horn is but touched with the two 
 firft: folutions, and expofed to the air, it 
 does not fail to acquire the colour in a few 
 hours : In the two latter, it requires to be 
 fteeged for a day or longer in order to its. 
 
 imbibing the colour. In thefe and other 
 cafes where immerfion for fome time is ne- 
 ceftary, the bone may be variegated by co- 
 vering fuch parts as are intended to remain 
 white, with Wax or any other matter that 
 the liquor will not diftolve or. penetrate. 
 
 There is a fingular induration of bones, 
 produced by fire; theeftedls of which agent 
 are here remarkably different, according to 
 its degree and the circumftances of its ap- 
 plication. Bones eXpofed to a moderate 
 fire, either in open veffels or in contadl with 
 the burning fuel, become opake, white and; 
 friable throughout ; and an increafe of the 
 fire, after they have once fuffered this, 
 change, renders them only more and more 
 friable.. But if they are urged at firft with; 
 a ftrong fire, fuch as that in which Copper 
 or Iron melts, they become hard, femitran- 
 fparent, and fonorous like the hard mineral; 
 ftones. • This curious experiment deferves; 
 to be further grofecute.d,. 
 
520 Bony Substances. 
 
 Ox-bone, had little effedt : Spirit of Sal ammoniac had none at all; and fixed alcalies, 
 
 ■ — * v — -J and cauftic Ley, did but (lightly corrode the bone : The volatile fpirit received 
 no colour; the cauftic Ley, a yellowifh one. 
 
 Two ounces of Ox-bone, diftilled in a retort, in an open fire, gave over two 
 drams of an empyreumatic phlegm, one dram of volatile urinous fpirit, two 
 fcruples of volatile Salt, and two fcruples of fetid Oil: The Caput mortuum 
 weighed one ounce three drams and two fcruples. 
 
 In another diftillation of Ox-bone, I obtained, from fixteen ounces of the 
 bone, eight ounces and a half of diftilled matter ; of which the urinous fpirit 
 made up four ounces fix drams and a half, the volatile Salt half a dram; 'and 
 the empyreumatic Oil three ounces five drams. The Caput mortuum weighed 
 fix ounces feven drams, and loft in calcination three drams: From the calx 
 were elixated by water twenty-feven grains of fixed Salt. 
 
 II. TH E branched horns of the Hart or male red Deer (the female has none) 
 
 Harts- are on their firft appearance quite foft, and covered on the outfide with a 
 horn, woolly matter : By degrees they contradt a ikin, which as the horn grows dry 
 U— v — — > and hard, peels off. This animal fheds his horns every year ; not as fome fup- 
 pofe, from their mere weight, fince they fall regularly at a certain feafon ; nor 
 from want of nourifhment, fince the moft plentiful lupply of food does not 
 prevent it ; nor from the young horns pufhing out the. old, for when the horns 
 are tawed over (liort, the flumps never fall off; but folely, as Stahl has ob- 
 ferved, from the adlion of cold, for young Harts, kept in warm (tails in the 
 winter, do not lofe their horns. 
 
 Sixteen ounces of Hartfhorn, boiled withw'ater, gave three ounces and three 
 drams of ftrongfirm gelly or gelatinous extract : From the refiduum, rectified 
 fpirit extradited nothing. Spirit applied at firft took up about four fcruples 
 from fixteen ounces ; this extradt confifts not wholly of oily, but of oily and 
 gelatinous matter. 
 
 From twenty-eight pounds of Hartfhorn, diftilled in an open fire, were ob- 
 tained near five pounds and a half of a fomewhat oily and urinous phlegm, 
 thirty ounces of a volatile Salt, and above a pound of empyreumatic Oil'(^) : 
 The remaining Coal or Caput mortuum weighed near feventeen pounds. The 
 coal burnt to whitenefs, diffolves both in the nitrous and marine acids, and is 
 precipitated from them by the vitriolic : An ounce of Spirit of Salt diffolved, 
 without much effervefcence, two drams twenty-one grains; and an ounce of 
 good Spirit of Nitre, three drams twenty-eight grains. 
 
 " The 
 
 ( b ) Produce of Salt , &c.] The author’s ex- 
 periments were made upon the cortical part 
 or tips of the horns, which contain more 
 gelatinous matter, and yield a larger quan- 
 tity of volatile Salt, than the internal me- 
 dullary fubftance. On diftilling a quantity 
 of fragments of Hartfhorn, confiding chiefly 
 of pith, I found the proportion of volatile 
 Salt to be only about half as much as in 
 our author’s experiment ; five hundred and 
 
 three pounds of the horns having yielded only 
 fixteen pounds of rough Salt, with ninety- 
 two pounds of rough Spirit and Oil. 
 
 The rough Salt o( Hartfhorn lofes in 
 rectification between one third and one half 
 of its weight. Two pounds three ounces, 
 on being rectified with Spirit of Wine, were 
 reduced to one pound four ounces and a 
 half. 
 
Bony Substances. 521 
 
 The Jelly, volatile Salt, Spirit, and rectified Oil of Hartfhorn, are of more Harts- 
 frequent ufe in medicine than thofe of any other animal fubftance. Hartfhorn horn. 
 has been a particular favourite among the pharmaceutical chemifts : Even its — •* — ■■ J 
 
 dead, fixed, indolent earth, deprived of all the aCtive principles of the horn, 
 has been celebrated as a medicine of extraordinary virtue. 
 
 Some prepare this earth, by fufpending the tips of the horns in the head of 
 a ftill during repeated diftillations of fimpie waters, till the aqueous vapour has 
 extracted the gelatinous parts, and rendered the horn puiverable; in which 
 ftate it is called Hartlhorn philcfophi catty prepared, or prepared without fire. 
 
 Others boil the horn in water direCtly ; and thus obtain, more expeditioufly, a 
 preparation juft as philofophical, and juft as ufelels. 
 
 The horn calcined to whitenefs in an open fire, and levigated into a fine 
 powder, called fimply prepared Hartfioorn, is ftill more perfectly diverted of its 
 gelatinous parts, and reduced to a pure earth : This is fometimes made an in- 
 gredient in powders for cleaning the teeth : It may likewife be of ufe for ob- 
 tunding acid humours in the rtomach, like other abforbent earths; but on 
 what pretence can we afcribe to it cordial, diaphoretic, alexipharmac, or anti- 
 febrile powers? Some endeavour to improve the medicine, by grinding the 
 earthy powder with Gold-leaf, and calcining the mixture tiil it acquires a purpie 
 colour: This preparation was formerly kept a fecret*, and if it was now for- 
 gotten, medicine would fuffer no lofs. 
 
 HALF an ounce of the Cranium humanum rafped, gave, with reclined Spi- III. 
 rit of Wine, two grains of an extraCt, which had no fmeil, and no particular Cranium 
 tafte. The fame quantity, treated with water, gave a dram of gelatinous ex- HUMANUM 
 traCt, inodorous like the other, but in tafte fomewhat faline. Spirit of Vitriol, 
 and Spirit of Sea-falt, totally diftblved the bone ; but Spirit of Nitre left a 
 fmall portion undiftolved : All the folutions were colourlels ; that made in the 
 vitriolic acid fhot into fine fmall white cryftals. Spirit of Sal ammoniac had no 
 effeCt*, folution of fixed Alcali corroded a little*, and cauftic Ley diftblved al- 
 raoft the whole : Thefe alcaline liquors received no tinCture any more than the 
 acids. 
 
 By gradual diftillation in a retort, I obtained from two ounces of the Cra- 
 nium , of urinous liquor three drams and a half, of empyreumatic Oil half a 
 dram, and of volatile Salt half a dram : The Caput mortuum weighed eleven 
 drams and a half. 
 
 This bone, the natural defence of the feat of fenfation and perception in the 
 nobleft animal, has been recommended medicinally as a cure for epilepfies, de- 
 liria, and all diforders of the fenfes . . . from the fame philofophy, which 
 afcribed antiafthmatic virtues to the lungs of the long-winded Fox ; and ex- 
 pected, becaufe fowls are faid to digeft even fmall ftones, that the fkin of the 
 gizzard, dried and powdered, would produce a fimilar effect in the human 
 
 rtomach To fuch lengths of extravagance have the fons of phyfick been 
 
 carried by the blind fuperftition of former ages ! 
 
 HALF an ounce of the Tusk of the Wild-Boar, digefted and boiled in 
 rectified Spirit of Wine, gave three grains of excraCt, of a rancid tafte. The 
 
 X x x fame 
 
 Boar’s 
 
 T USK. 
 
522 Bony Substances. 
 
 Boar’s fame quantity yielded with water half a dram •, this extract gave out marine 
 Tusk, vapours on the affufion of Oil of Vitriol, and Was found to confift chiefly of 
 common Salt. The bone, after boiling in fpirit, looked reddifh ; but water 
 made no change in the colour. 
 
 This bone was totally diffolved by Spirit of Vitriol and Spirit of Nitre, and 
 almoft totally by Spirit of Salt-, to the firft it communicated a yellowifli tinge, 
 to the two latter none j from the firft it cryftallized, in form of a fubtile Salt. 
 Spirit of Sal ammoniac had no adtion on it ; folution of fixed alcaline Salt cor- 
 roded a little of it, without acquiring any colour ; cauftic Ley corroded almoft 
 the whole, and appeared of a pale Rofe-red. 
 
 From two ounces of the Tufk, diftilled in an open fire, there arofe five 
 drams and a half of urinous liquor, two fcruples of empyreumatic Oil, and a 
 dram and a half of volatile Salt : The refiduum weighed one ounce and a 
 fcruple. 
 
 y o TH E Hippopotamus is an amphibious quadruped, inhabiting chiefly the 
 
 Hippopo- Iar g e rivers of Africa and Afla, as the Nile, the Niger, the Bamboth, the 
 T ;iJ S Zaire in the kingdom of Congo, He is called Hippopotamus or river -horfe 
 
 t _> from the fhape of his head, Bupotamus or river-rw from the hinder part of the 
 
 body, and the river -elephant from the fize of his fore-teeth. Bochartus endea- 
 vours to prove that this animal is the Behemoth mentioned in Job. When full 
 grown, he is thirteen feet long, and twice as thick in the body as an Ox ; the 
 legs are fhort and thick ; the head is three feet in length and very thick, the 
 mouth above a foot wide : The fkin is remarkably ftrong, being half an inch 
 in thicknefs when dry, and hence it is ufed in fhields for defence : A piece of 
 the fkin, and fome other parts of the animal are preferved in the Mufeum of 
 the Royal Society. 
 
 The fore-teeth of the River-horfe are for the moft part bent femicircularly, 
 ftriated longitudinally on the furface, with a deeper furrow in the curvature. 
 They are hollow internally, but lefs and lefs fo towards the extremity, which is 
 pointed nearly like the tufk of the wild Boar. They are of different fizes : The 
 iargeft weigh four pounds. They are extremely compadt; fo hard as to ftrike 
 fire with good Steel externally of a yellowifh-white colour, unlefs tarnifhed by 
 age, or filth adhering to the unequal furface \ internally of a fine white, which 
 is lefs apt to change to a yellow than that of other bones. From their com- 
 padtnefs and durable whitenefs, they are employed like Ivory, for fundry me- 
 chanic ufes. 
 
 This bone contains little oily or inflammable matter. From hair an ounce, 
 rafped into powder, I obtained, by digeftion and boiling with Spirit of Wine, 
 no more than one grain of extradl, which was of a blackifh- brown colour, and 
 had very little tafte or fmell. The fame quantity being boiled with water, and 
 the decodtion evaporated, there remained thirty grains of a yellowiih mafs, te- 
 nacious like Glue, and to the tafte quite faline. The bone remaining after the 
 adtion of both menftrua appeared unchanged in colour. 
 
 Spirit of Vitriol totally diffolved it : Spirit of Nitre and Spirit ofSea-fak 
 left a little flaky matter : The folutions in the vitriolic and marine acids looked 
 yellowiih, that in the nitrous, colourlefs : From the firft, a fmall quantity of 
 
 5 faline 
 
Bony Substances. 523 
 
 faline matter cryftallized. Spirit of Sal ammoniac, ftrong alcaline Ley, andHippopo- 
 cauftic Ley, corroded a little of the bone, and acquired a yellowilh tinge. tamus. 
 
 Two ounces diddled in a glafs retort, at firft with afand-heat and afterwards v — -v — -J 
 with an open fire gradually increafed, yielded four drams and a half of a volatile 
 urinous empyreumatic liquor, and half a dram of a reddifh-black empyreu- 
 matic Oil : The remaining coal weighed ten drams two fcruples. During the 
 didillation, an adlual volatile Salt concreted about the fidesof the receiver, but 
 on continuing the procefs it was diffolved and waffled down, its quantity being 
 too fmall to be collected in its folid form. 
 
 THE tooth of the Sea-horse has been generally confounded with that of VI. 
 the River-horfe, and fubdituted to it in the (hops. The Sea-horfe, Rofmarus, Sea-horse. 
 equus marinus , ieo marinus , elephantus marinus , is a large amphibious marine 
 quadruped, found in the northern leas, about the coads of Greenland, Iceland, 
 and Nova Zembla: It is called by the Germans the Horfe-whale. The teeth 
 of this animal are naturally of a fine white, though we commonly meet with 
 them tarnifhed to a yellowilh : They are very hard and compact, more or Ids 
 bent, pointed at the end like thole of the River-horfe, but lefs hollow, the bol- 
 lownefs reaching only a little way from the root: The larged weigh three 
 
 pounds and a half. The fkin of one of thefe animals has been known to weigh 
 five hundred pounds. The tooth is ufed as Ivory, not only by the northern 
 nations, but likewife among the Turks, Cofiacks, Ferfians, £br. for fword-hilts, 
 hafts of knives, and a variety of toys. The teeth both of the Sea and River- 
 horfes are made alfo into rings, necklaces, bracelets, from a whimfical 
 conceit o* their being good againd cramps. 
 
 From half an ounce of the fine rafpings of the tooth of the Sea-horfe, 1 
 obtained, by digedion and codlion in Spirit of Wine, only half a grain of ex- 
 trad ; and this feemed to proceed rather from fome extraneous foulnefs adher- 
 ing to the bone, than from the bone itfelf; it was of a brownifli colour, and 
 had neither tade nor fmell. Another half ounce, boiled with diddled water, 
 yielded twenty-five grains of a glutinous tenacious mafs, of a yellowilh- white 
 colour and faline tade. The bone itfelf differed no change in its colour either 
 from water or fpirit. 
 
 All the mineral acids diffolved it •, with this difference, that the nitrous and 
 marine left a fmall quantity of flaky matter, whilff the vitriolic took up the 
 whole : From the vitriolic folution a little white cryffaliine fubdance feparated, 
 as from the dilutions of other bones made in that acid. The nitrous dilution 
 looked yellowilh. Alcaline mendrua had no effect, except that a dilution of 
 fixed Alcali made the powder grey and blackfill. 
 
 From two ounces of the rafped bone, diddled in a giafs retort, at nrft in 
 fandand afterwards in an open fire gradually railed, were obtained a dram and 
 a half of clear water, two fcruples and a half of urinous, oily, empyreumatic 
 liquor, two fcruples of reddifh-black fetid Oil, and a dram and a half of fine 
 cryffaliine volatile Salt : The Caput mortuum weighed one ounce three drams 
 and a half. 
 
 This tooth differs therefore, chemically, from that of the. Hippopotamus, in 
 giving out lefs to water and to fpirit, and nothing to alcaline liquors 3 in being 
 
 X x x 2 changed 
 
524 Bony- Substances. 
 
 Sea-horse, changed to a blackifh grey colour by folution of fixed Alcali ; tinging the 
 u**~,/«***J nitrous acid yellow, and not the vitriolic ; yielding in diftillation lefs 
 urinous liquor, more Oil and Caput mortuum, and much more volatile Salt, 
 and not only an aftual fetid fait, but what is remarkable, a cryftalline one. 
 
 VII. IVORY is a tufk, or tooth of defence, growing at each fide of the jaw 
 Ivory, of the male Elephant •, the female has only the fmaller grinding teeth. The 
 I - Elephant is diftingui fhed from other animals by its fize, its tufks, its trunk or 
 
 fnout, (which it lengthens, fhortens, and bends at pleafure, and ufes as a 
 hand,) and its thick roundifh hoofs. It is the largeft of all land animals, and 
 remarkably docile. In Afia and Africa, its native climates, great numbers 
 are tamed and trained up by the grandees, for war, for carriage, for amufe- 
 ment, and for fhow. Du Verney diffedted an Elephant at Paris in 1681, and 
 an abftradt ol his obfervations is publifhed in Du Hamel’s hiftory of the Aca- 
 demy of Sciences ; but a much better and more particular anatomical defcrip- 
 tion of this animal may be feen in Ray’s hiftory of Quadrupeds. 
 
 The Elephant’s tufk is accounted by fome not to be a tooth but a horn* 
 becaufe, fay they, it foftens in the fire, which horns do and teeth do nor. 
 Ivory, however, does not grow foft like common horn, but continues brittle, 
 and by degrees calcines : Of horns, in the common fenfe of the word, it is 
 no character to grow foft in the fire •, for thofe of leveral animals, as the Hart 
 and the Elk, do not. Ivory is a true and perfedt tooth, and the largeft tooth 
 in the world. Sometimes it grows to an enormous fize : Vartomannus faw two 
 in Sumatra which weighed together three hundred and thirty-fix pounds; and 
 Einfchott mentions a fingle one which weighed above two hundred pounds. 
 The moft common fize, however, in trade, is from four to fifteen pounds, 
 the very large ones being kept as curiofities. 
 
 The entire tooth is of a yellowifh, brownifb, and fometimes a dark brown 
 colour on the outfide, internally white, hollow towards the root, and fo far 
 -as was inferted into the jaw of a blackifh brown colour. The fineft, whiteft, 
 fmootheft, and moft compadt ivory, comes from the ifland Ceylon. The 
 grand confumption of this commodity is for making ornamental utenfils, ma- 
 thematical inftruments, cafes, boxes, balls, combs, dice, and an infinity of 
 toys. There are many exquifite pieces of workmanship, as medals and chains, 
 curious fpinning-wheels, &c. made entirely out of one tooth. In his Pruffian 
 Majefty’s dolledlion, there is a chair, a pair of chefs tables, and fundry other 
 curiofities of ivory. The workmen have methods alio of tinging it of a variety 
 of colours. 
 
 Four drams of rafped ivory yielded, with redtified Spirit, three grains of 
 extradt, in tafte fomewhat rancid, but of no fmell : the remainder inclined a 
 little to reddifh. On boiling four drams in pure diftilled water, and infpif- 
 lating the decodtion, I obtained fix drams of jelly or a gelatinous extradt; but 
 as the dried refiduum weighed three drams and a fcruple, it is plain that in the 
 fix drams of jelly there were only two fcruples afforded by the ivory, all the 
 reft being water ; and hence we learn, what a large proportion of water is re- 
 tained in jellies. The jelly tailed manifeftly faline; the remaining ivory 
 proved confiderably brittle and earthy. 
 
 Spirit 
 
Bony Substances. 525 
 
 Spirit of Vitriol totally diftolved rafped ivory : from the foliation there fe- Ivor y. 
 parated an elegant, white, Iparkling, filky, cryftalline mixt, in appearance J 
 
 refembling a fait, but neither faline to the tafte, nor difToluble in water-, of 
 the fame kind alfo are the cryftals obtained by this acid from the other folid 
 parts of animals : the liquor, floating above the cryftals, is apt to become 
 yellowifh, and at length brown. 
 
 Spirit of Nitre and Spirit of Salt likewife diffolved the whole of the ivory, 
 but received no colour, and yielded no cryftals. Spirit of Sal ammoniac had 
 no effed: Alcaline Ley corroded a little of the ivory, without acquiring any 
 tinge : Cauftic Ley totally corroded it, and became fomewhat yellowifh. 
 
 Lemery lays that ivory contains much Oil, volatile Salt and Earth, but 
 little Phlegm : I have found on the other hand, that the Oil is in the fmalleft 
 quantity of all thefe principles, and that the Phlegm is in larger quantity 
 than either the Oil or Salt. From two ounces, diftilled in a retort, I obtained 
 three drams and a fcruple of liquor, of which the firft two drams fmelt like 
 fope, and the reft empyreumatic and urinous : This was fucceeded by two 
 fcruples of fetid Oil, and two drams of volatile Salt. The remaining coa! 
 weighed ten drams. 
 
 The coal of Ivory is of a fine deep black colour 5 and hence is tiled as a ivory-black, 
 pigment by the painters under the name of ivory-black ; as alfo by the lapi- 
 daries, as a foil for precious ftones; and by the japanners and varnifh makers, 
 as an ingredient in their black compofitions There are particular machines 
 and contrivances for burning the Ivory for thefe purpofes by which the co- 
 lour is rendered more beautiful than that of the coal which remains in the 
 diftil iation . 
 
 If the Ivory-black be calcined in the open air, it changes into an earth of 
 extreme whitenefs : By deflagrating two parts of rafped Ivory with three of 
 Nitre, it is quickly reduced into a fimilar white powder, without any inter- 
 mediate ftate of blacknefs. 
 
 THE Carp-Stone, Lapis carpionum , is found in the head of a fifh, VIII. 
 which is not the common carp, but the gilt chart, the cyprinus of Ronde- Carp-stone. 
 letius. It is not, what Lemery calls it, the os hyoides , but a bone lodged in v-”—' 1 
 the acetabulum , at the juncture of the backbone with the head. When frefh, 
 it is moderately tranfparent, like horn, in colour whitifh or yellowifh by keep- 
 ing it becomes more and more yellow and brown. In figure it is flat, and 
 irregularly triangular, 
 
 Half an ounce of this bone, rafped final!, yielded with rectified Spirit of 
 Wine five grains of extrad, which tafted and fmelt quite rancid, like old dry 
 fifh. From the fame quantity , boiled in water, I obtained a dram of extrad, 
 of a yellow colour, in tafte purely faline, without any fmell. The bone re- 
 maining after the adion of Spirit, looked like tranfparent yellow amber; that 
 which had been boiled in water looked grey. 
 
 Spirit of Vitriol corrodes only a little of the bone, and by that little is ren- 
 dered turbid : Spirit of Nitre aiffclves' nearly the whole, and acquires a yellow 
 colour : Spirit of Salt diftblves a little, and becomes likewife yellow. Spi- 
 rit of Sal. ammoniac has no effedr, Alcaline Ley corrodes a little, reeives no 
 
 colour 
 
526 Bony Substances. 
 
 Carp-stone. colour itfelf, but makes the bone black: Cauftic Ley diffolves and corrodes a 
 part, and acquires a yellow tinge. 
 
 Two ounces of the bone, diftilled in a glafs retort, in an open fire gradually 
 railed, gave over half an ounce of liquor, of which the firft three drams had 
 an extremely ill fmeil, but the fourth the common urinous empyreumatic one; 
 Thenarofe a dram and a half of fluid Oil, three drams of a thicker one, and 
 three drams and a half of volatile Salt : The remaining coal weighed half an 
 ounce. 
 
 THE Perch-stone, Lapis per carum, is a fmall fiat oval bone, hollowed 
 a little at one fide, in figure fomewhat refembling a flatted grain of Rice, of a 
 gloffy whiteneis ; found in the head, near the origin of the back-bone, not of 
 the common Perch ( Perea major) but of the ruff" ( Perea minor , cernua , afpredo.) 
 
 Half an ounce of this bone, reduced to powder, yielded with rectified fpirit 
 only half a grain of extract, which had neither fmeil nor tafte. The fame 
 quantity gave with water two fcruples and a half of a yellowifh mafs, which was 
 almoft mere Salt. The bone itfelf fuffered no change in' its appearance from 
 either menftruum. 
 
 Spirit of Vitriol and Spirit of Salt, totally diflblved the bone ; Spirit of Nitre 
 left a fmall matter undiflolved : The firft acquired a yellowifh colour and de<- 
 
 pofited elegant cryflals ; the two others received no tinfture, and yielded no 
 cryftals. Spirit of Sal ammoniac, alcaline Ley, and cauftic Ley, corroded 
 very little, and were not fenfibly tinged. 
 
 In thefe experiments, the Perch-ltone difeovers no confiderable differences 
 from other bony fubftances ; but its analyfis by fire is very Angular and re- 
 markable. Two ounces diftilled in a glals retort, at firft in a fand-heat, and 
 afterwards in an open fire, gave over bare half a dram of a clear liquor, juft 
 verging to yellowifh, in fmeil only (lightly volatile and empyreumatic : The 
 greateft force of fire would raife nothing more : There was neither Oil, nor vo- 
 latile Salt, nor hardly any marks of an animal nature. The Caput mortuum 
 however was a black coal, like that of other bones; it weighed two ounces as 
 at firft, wanting only the half dram of phlegmatic liquor. 
 
 X. THE Pike is a frefh water filli of prey, with teeth only in the lower jaw. 
 
 Jaw of the^d t0 be of great longevity, and to grow by age to a prodigious lize : I have 
 Pike. ^ een f° me of thirty and thirty-two pounds weight. There are none of thefe 
 
 t j fillies in Spain ; nor any name for them in that language. 
 
 Half an ounce of the lower jaw-bone of the Pike, reduced into powder, 
 yielded with rectified fpirit five grains of extradr, of a rancid tafte, without any 
 imell ; the remaining powder looked reddifh. From the fame quantity were 
 obtained by water three fcruples and a half of a greenifh-yellow mafs, confid- 
 ing of a glutinous fubftance mixed with a large proportion of common Salt; 
 the refiduum appeared unaltered. 
 
 1 he vitriolic and nitrous acids totally diflblved the bone; the marine left a 
 fmall portion undiffolved : The folutions made in the two laft were colourlefs ; 
 that in the firft was yellowifl), and depolited a little cryftalline matter. Spirit 
 
 of 
 
 IX. 
 
 Perch- 
 
 stone. 
 
Bony Substances. 527 
 
 Sal ammoniac, common alcalineLey, and cauftic Ley, corroded only a little, Jaw of the 
 and received no colour. Pike. 
 
 From two ounces, diftilled in a glafs retort in an open fire, there arofe a dram C— — v — 
 and a half of liquor of a lixivial fmell, four fcruples of liquor of the ufual em- 
 pyreumatic fmell, a dram of empyreumatic Oil, and a dram and a half of vola- 
 tile Salt : The Caput mortuum weighed ten drams and a half. 
 
 THE Manati or Sea-cow is a large animal, of a peculiar kind. It is XI 
 ftridtly an inhabitant of the l’ea, but cannot live long without frefh water, and Lapis 
 feeds on grafs and other vegetable matters; hence it is never leen but near the Manati. 
 mouths of large rivers. It is met with in various parts of Afia, Africa and ' — — — > 
 America ; but in none of the European feas. It has two very fhort legs, 
 which ferve rather as hands than as feet, for though called amphibious, it never 
 comes entirely on fhore. It is very harmlefs, and eafily caught. The female 
 is viviparous, fuckles her young like thofe of the human fpecies, and carries 
 them conftantly in her paws •, hence it is called by the Spaniards and Portuguefe 
 la Donna. The flefti is faid to be much efteemed in America, and the ftrong 
 Ikin to be ufed as a defence againft the arrows of the Indians. 
 
 Certain bones found in the head of this animal, called Lapides manati , are 
 expedted to be kept in the flops for medicinal ufe; and the druggifts do not 
 fail to fupply us with a great variety of bony fubftances under this name, very 
 different from one another both in figure and in fize, and none of them the ge- 
 nuine bones of the Manati : Hence the different accounts of the Lapis manati 
 given by authors ; fo-me defcribing it as of the fize of a Hazel-nut, and others 
 as large as a child’s head. The Dutch put off' cod’s-head bones for thofe of 
 the Manati, and allure us that they come from America. 
 
 A S the true Lapis manati is not in this country to be procured, I examined 
 the fubffance which is moll generally fubffituted for it, namely the ear- bone of 
 the Whale. 
 
 From half an ounce of this bone, by digeftion and codlion in redtified fpirit, 
 
 I obtained only one grain oi an extradt which had neither fmell nor talte : From 
 the fame quantity, treated with diftilled water, I got a dram of a yellowiffi 
 mafs, which had no fmell but a very faline tafte, and which in effedt was little 
 other than mere common Salt. The powder fuffered no change in colour 
 from either menftruum. 
 
 Spirit of Vitriol totally diffolved the bone, depofited a fine white cryftalline 
 matter, and became yellowiffi. Spirit of Nitre and Spirit of Sea-falt diffolved 
 nearly the whole, without receiving any colour. Spirit of Sal ammoniac had 
 no effedt. Common alcaiine Ley, and cauftic Ley corroded a little of the 
 bone, but continued colourlefs : The powder, remaining after the adtion of 
 the plain Ley, looked blackifli. 
 
 From two ounces of the bone, diftilled in an open fire, I obtained a dram 
 of phlegm of a lixivial fmell, a dram of volatile fpirit or empyreumatic urinous 
 liquor, half a fcruple of fetid Oil, and half a dram of volatile Salt: The re- 
 maining coal weighed thirteen drams and a fcruple. 
 
 HALF 
 
5 2 8 
 
 Bony Substances. 
 
 XII. H A L V an ounce of the Ancle-bone of the Hare, Talus leporis , yielded 
 Talus 'with redtified ipirit fifteen grains, or one fixteenth its weight, of an undtuous, 
 Leporis. yeilowifti brown, tranfparent extract, of a rancid tafte and fmell. Another 
 half ounce, treated with water, gave a dram of a yellowifh matter, which had 
 no fmell, and was almoft mere Salt. Both the refidua were of the fame colour 
 as at firft. 
 
 By Spirit of Vitriol it was corroded ; a part feparated in a cryftalline form, 
 and the red was reduced into a white powder. The lpirits of Nitre and Sea- 
 fa k totally difib! ved it ; the folutions were clear, with an undtuous matter on 
 the furface, which in the nitrous acid was white, in the marine of a brownifh- 
 yeliow. Spirit of Sal ammoniac had no effedl, except that it acquired a flight 
 yellowin'! tinge, with a kind of cloudinefs towards the furface, as if a fine pow- 
 dery fubftance was fufpended in it. Strong alcaline Ley took up more of the 
 bone, and became yellower : Cauftic Ley did not feem to diflolve fo much. 
 
 Two ounces diftilied in a glals retort, at firft in land and afterwards in an 
 open fire, gave over two drams of a liquor of a quite fopy' fmell, one dram of 
 an empyreumatic urinous liquor or fpirit, four fcruples of empyreumatic Oil, 
 and two drams of volatile Salt : The Caput mortuum weighed nine drams two 
 fcruples. 
 
 THE Unicorn is not a land animal of the Horfe kind, as fome have re- 
 Unicorn’s Patented it, but a lpecies of Whale common in the northern Teas, called by the 
 Horn. Icelanders Narhual or Narwal , that is the Carrion-whale, its food being the 
 i_ ' carcafies of men and fifties. The horn, as it is called, is a large tooth fixed in 
 
 the upper jaw : As the tufks of the Sea-horfe are bent downwards, and thofe of 
 the Elephant, the Boar, and the oriental Wild-boar called Babyroufla, up- 
 wards ; that of the Narwal ftands horizontally, and in this refpedt only it dif- 
 fers from the fangs of thofe animals. 
 
 The tufk of the Narwal is very large ; fome have been feen of the length of 
 nine or ten feet. It is pointed at the end, fometimes irregularly crooked, in 
 colour more or lefs white, generally wrinkled and undulated as if the bone was 
 twifted, fometimes, but very rarely, of a fmooth poliflied furface. The part 
 that had been inlerted into the jaw, is commonly of a yellower or browner co- 
 lour, and more unfightly, than the reft. Towards the root, there is often a 
 confiderable part hollow : I have been afiured by the mafter of a Greenland 
 veftfel that the hollow teeth are decayed ones which the animal has fhed, and 
 that the found ones, taken immediately from the Whale, are folid throughout. 
 This tooth, like other bones, is made into various toys and utenfils : The 
 
 Greenlanders ufe the tips for pointing their hunting weapons. 
 
 Half an ounce of this bone, rafped into powder, yielded with rectified fpi- 
 rit, two grains of an infipid and inodorous extract. From the fame quantity 
 were obtained by water three fcruples and a half of a browniih-yellow, tenaci- 
 ous, -undtuous mafs, of a faline tafte without any fmell. The refiduum, in both 
 cafes, was of the fame appearance as at firft. 
 
 All the mineral acids totally diflolved the bone, without receiving from it 
 any colour ; from the folution made in the vitriolic, a little cryftalline matter 
 
 feparated. 
 
Earthy Parts of Animals. 
 
 5 2 9 
 
 feparated. Spirit of Sal ammoniac and alcaline Ley had no effect ; cauflic Unicorn’s 
 Ley corroded a little of the bone. Horn. 
 
 By diftillation in a retort, in an open fire, I obtained from two ounces of 
 the bone, of urinous fpirit four drams, of an empyreumatic Oil half a dram, 
 and of volatile Salt two fcruples and a half : The Caput mortuum weighed ten 
 drams two fcruples. 
 
 SECT. VI. 
 
 XL 
 
 fs of Animals, 
 
 ORN S and bones confift in great part of an earth, but are neverthelefs Earth 
 
 very diftind: from the bodies of the prefent divifion. The earthy parts 
 of animals, more ftridtly fo called, are of a much lefs compact texture 
 than the horny and bony, and want not only the flexibility of the one but the 
 hardnefs of the other. They break far more eafily by a blow, and are re- 
 ducible in the mortar into powder. They yield in general lefs oily and faline 
 matter in diftillation, and contain in their natural ffate lefs gelatinous matter-, 
 whence they diffolve, not only in the ftrong mineral acids, but in the milder 
 acids of the vegetable kingdom, the gelatinous parts being infufficient to cover 
 and defend the earth from the adtion of the acids. 
 
 Of this kind are moft of the teftaceous and cruftaceous coverings of animals, 
 and many calculous concretions. The pure earthy part is not in all thefe fub- 
 flances the fame, nor are the particular differences fufficiently known. The 
 only confiderable difference that has been obferved, is, that fome are converted 
 by fire into a ftrong Quick-lime, whilft others buffer no fuch change. [See 
 page 4 93-J 
 
 Vo 
 
 CLASS I. 
 
 Earthy Sitbjlances not convertible by Fire into Quick-lime ; and whofe 
 Earth feems to be fimilar to that of Bones and Horns. 
 
 F all the fubftances of this clafs, and indeed of all the earthy parts of p E ARLs 
 animals, the moft valuable and remarkable is the Pearl •, which from 
 its beauty and luftre is ranked among the precious ftones, though it has no- 
 thing of their diftinguifhing hardnefs. 
 
 Pearl is no other than a calculus, or morbid concretion, produced in a certain 
 fhell-fifh of the Qyfter kind, and fometimes in common Oyfcers and Mufcles : 
 
 It is fometimes formed upon the infide of the fhell, and fometimes in the body 
 of the animal. Shells in general appear to proceed from peculiar nutritious 
 juices, regularly fecreted and indurated; and Calculi, from a redundance of 
 
 Y y y thole 
 
53° Earthy Parts of Animals. 
 
 Pearl, thofe juices, or a ffagnation and unequal diftribution of them occafioned by an 
 ^ obftrudtion of the veffels. 
 
 Pearl-£fhery. The Mother- of- Pearl fifh, or Pearl oyfter, is an inhabitant of the bottom 
 of the fea : There it abides fixed, and is not to be come at but by diving. A 
 number of fmall fhips is generally engaged together in this dangerous bufinefs, 
 on fuch particular fpots as have been found to be rich in the Pearl-fifh, and ac 
 certain feafons of the year. The divers are let down by ropes, and immedi- 
 ately drawn up again upon their pulling a bell as a fignal for that purpofe. 
 Machines have been contrived for enabling them in fome degree to breathe at 
 the bottom, by means of pipes reaching above the furfaceand communicating 
 with the external air, or by a quantity of air included and carried down with 
 them : See fome papers upon this fubjeft in the Philofophical Tranfadtions. 
 Suffocation however is not the only danger to which the divers are expofed : 
 They are fubjedt to ruptures of fome of the veffels from the vaft preffure of the 
 water at great depths, and to be wounded or devoured by fifhesof prey, which 
 fome of the rich beds of Pearl-fifh are fo much infefled with, that fcarcely any 
 one can venture down at all. 
 
 After the Pearl-oyfters have thus been got up, there ftill remains a procefs, 
 not a little prejudicial to health, and extremely offenfive. If the fhells were 
 opened diredtly by any violent means, the Pearls, faid to be at this time in a 
 fomewhat folt date, would be liable to be injured, and become of little value. 
 The whole are therefore laid in heaps, till the fhells open fpontaneoufly, and 
 the fifh putrefies ; after which the corrupted cadaverous matter is fearched di- 
 ligently for the Pearls, which are often too few to pay the expence of the pro- 
 prietors, much lefs to make any recompence to the workmen for a fervice fo 
 loathfome and fo hazardous. 
 
 Different forts Pearls areufually divided into oriental and occidental ; the firft produced in 
 and places of A fia and Africa, the latter in America and Europe. The principal oriental 
 produdbon. p ear ] ft fineries are in the Perfian gulf and on the coafts ofPerfia and Arabia, 
 of which a chart may be feen in Kaempfer’s Amanitates Exotica ; near the 
 iflands Ceylon, Manaar, Sumatra, Java and Borneo; on fome of the coafts of 
 Japan ; between Banana and Cochin, off Cape Comorin, and in other parts 
 along the Malabar coaff, as particularly at Tutogrin or Tutocoryn, where 
 there is an excellent Pearl bank in poffeffion of the Dutch. The mod remark- 
 able Pearl fifheries of America are in the gulf of Mexico, along the coaff of 
 New Spain, off St. Margarite or the Pearl-ifland, in the Rio de la Hacha, at 
 the iflands St. Martha, Quibo, Gorgonia, (s?c. In Europe, Pearls are now 
 and then met with on the coafts of Scotland, Livonia, Courland,. in the river 
 Iks in Bohemia, in the Regen in Bavaria, in certain lakes near Augfburg, and 
 in fundry other places. 
 
 The oriental Pearls are accounted the beft; and, confidered colledfively, 
 they certainly are fo, though this fuperiority by no means extends to all the 
 individuals r There are fome, among the occidental, of exquifite luftre and 
 great value; and many millions, among the oriental, coarfe and unfightly. 
 
 Even among the better kinds of oriental Pearls, there are very confiderable 
 differences ; Borneo affords the largeft, and Ceylon and Manaar the whiteft : 
 Thofe of Sumatra* Java, Panana, Cochin, and the Malabar coaft, are for the 
 
 moft 
 
Earthy Parts of Animals. 531 
 
 mod part fmaller and Iefs fine : Thofe of the Perfian gulf have generally fome- 
 what of ayellowifh caff, but as they conftantly retain this tinge, and have an 
 excellent luftre, they are accounted the beft, and fome confine the name of 
 oriental to thefe alone. 
 
 There are Pearls of various colours, figures, and magnitudes; of an ex* 
 quifite Silver-like brightnefs, femitranfparent, opake, opal-coloured, yellow, 
 greemik, bluifh, greyilk, redd ilia, brownifh, blackifh, rainbow-coloured ; 
 round, oval, conical, cylindrical, angular; from the fize of a Millet-feed or 
 lefs, to that of a Hazel-nut and more : It is obfervable that the large ones ap- 
 proach generally to the figure of a Pear. The larged Pearl hitherto known is 
 defended by Tavernier, and is in the poffeffion of the King of Perfia; it was 
 found atCatifa in Arabia, and cod 1,400,000 French livres. Some years ago, 
 there were two very large ones to be difpofed of at Leipzick, weighing toge- 
 ther above ninety carats: The author above-mentioned had one that weighed 
 fifty-five carats : A carat is three grains* and a half. I have feen a Pear! in the 
 Engliih crown, which is faid to be worth ten thoufand pounds deriing. Sir 
 Robert Sibbald fays in his Scotia lllujlrata, that Pearls have been found in Scot- 
 land of a very large fize. 
 
 Pearls are valued from their roundnefs, their fize, and their water, that is Their valua- 
 their ludre and purity. Their weight is edimated in Europe by carats ; in tion - 
 Perfia by abas' s, and in Golconda and Vifapour by ratis, each abas and rati be- 
 ing one eighth part lefs than a carat. 
 
 The weight of round Pearls is expeditioufly judged of, by means of a fmall 
 inftrument compofed of feveral flips of Brafs full of holes of diderent fizes : 
 
 The fmallefl hole receives a Pearl of one or two grains ; and the larged, one of 
 ten carats ; and thus the weight of any given round Pearl is known from the 
 hole which it fits. 
 
 Small irregular ones are valued from the number that goes to an ounce : If a 
 hundred make an ounce, they are valued at an hundred rixdollars ; if the 
 number is lefs, the price is greater; and if the number is greater, the price is 
 lefs: Two hundred to the ounce cod but feventy rixdollars; three hundred, 
 fifty; nine hundred, ten; two thoufand, three; four thoufand, two and a half: 
 
 Of the very fmall fort called Seed-pearls, ufed in medicine, an ounce contains 
 ufualiy eight or ten thoufand, and cods, if the Pearls are of the oriental kind, 
 two rixdollars, if occidental one rixdollar and twelve grofchen(c). 
 
 Attempts have been made to take out dains from Pearls, and to render thecieaned. 
 foul, opake, coloured ones equal in beauty and ludre to the oriental. Abun- 
 dance of procefles are given for this purpofe in books of fecrets and travels ; 
 but they are very far from anfwering what is expected from them. Pearls may 
 be cleaned indeed from any external foulnefs, by walking and rubbing them with 
 a little Venice Sope and warm water, or with ground Rice and Salt, with 
 Starch and Powder-blue, with Plader-of-Paris, with white Coral, with white 
 Vitriol and Tartar, with Cuttle-bone, Pumice-done, and other like fubdances ; 
 but a dain that reaches deep into the fubdance of the Pearl is impoffible to be 
 taken out. Nor can a number of fmall Pearls be united, as fome pretend, into 
 a mafs fimilar to an entire natural one. 
 
 There 
 
 {c) Rixdollar.'] A rixdollar is equal to 4;. 6 d. A grolTchen about id. Y y y 2 
 
Earthy .Parts of A n i u a l s . 
 
 There are however methods of making artificial compofitions, equally orna- 
 mental with the natural Pearls, and difficultly if at all to be diftinguifhed from 
 them by the eye. Mofl of thefe are prepared in France and Italy, and Ibrne in 
 Spain: The belt confift of a hollow glafs ball, blown by a lamp, and filled 
 with Wax : Some pour in fir ft a Solution of a certain Amalgam, and then (ill 
 up the ball with Wax : Others ufe Wax without Glafs, anci by certain additi- 
 ons communicate a Pearl colour on the out fide. This curious art is kept a 
 fecret in the hands of the workmen {d). 
 
 Powdered Pearl gives out nothing to water or to rectified fpirit, by long di- 
 ■geftion orcoftion. It difiolves in the. mineral acids, totally in the vitriolic, 
 and almoft totally in the nitrous and marine, without communicating to them 
 any perceptible tinge: From the folution in the vitriolic acid there fepa- 
 rates a cryftalline matter, in appearance refe-mbling a Salt. It is not abled upon 
 by Spirit of Sal ammoniac orcauftic Ley : By plain alcaline Ley a little of the 
 Pearl was corroded into a flaky fubftance. 
 
 Four drams of Pearl, diftilled in a glafs retort with an open fire gradually 
 increafed, gave over fourteen grains of an empyreumatic urinous liquor, of a 
 volatile fmell, with feme footfteps of an empyreumatic Oil in the neck of the 
 retort. The Caput mortuum was of an afh-grey colour, and weighed three 
 drams twofcruples fix grains : This being further calcined in an open vefiel, 
 then elixated with water, and the Lixivium filtered and evaporated, I obtained 
 five grains of a fixed Salt, which appeared of a fine white colour, had a warm 
 not very faline tafte, eftervefeed with Oil of Vitriol, and during the effervefcence 
 difeharged in vapour a little marine acid. 
 
 All thefe experiments were performed both upon oriental and occidental 
 Pearls-, and no difference could be obfervea betwixt the two, either in the quan- 
 tity or quality of the products, excepting that the occidental Pearls yielded in 
 diftiilation four grains more of liquor than the other, and that the Caput mor- 
 tuum of courie weighed four grains lefs. 
 
 STONY concretions are formed in many land animals; in the ftomach 
 of Goats, Hares, Horfes, AiTes, Cows, as well as in the urinary and gall- 
 bladder of the human body ( e ). Several of thefe fubftances were by the cre- 
 dulity 
 
 (d) Artificial Pearls.'] The ingredient em- 
 ployed for giving the colour is a fine Silver- 
 like fubftance found upon the under-fide of 
 the feales of the Blay or Bleak-fifh. The 
 feales, taken off in* the ufual manner, are 
 waftved and rubbed with frefh parcels of fair 
 water, and the feveral liquors fuffered to 
 fettle : The water being then poured off, 
 the pearly matter remains at the bottom, of 
 the confiftence of Oil, called by the French 
 EJJence d'orient. A little of this is dropt into 
 a hollow bead of bluifti Glafs, and fhaken 
 about fo as to line the internal furface ; after 
 which, the cavity is filled up with Wax, to 
 
 give folidity and weight. By this means 
 Pearls are imitated in fuch perfection, as 
 not to be.diftinguifhable by the eye from the 
 natural, or to be diftinguiftiable only by 
 their having fewer blemifhes. See a Me- 
 moir on this fubjeCt by M. de Reaumur, in 
 the Mem. de t Acad. Royale de Sciences ( de 
 Paris ) pour I'ann. 17x6. 
 
 (e) Human calculus.] This concrete varies 
 greatly in confiftence : Sometimes it is of a 
 loofe texture, and almoft friable betwixt 
 the fingers ; fometimes very hard and corn- 
 pad, and capable of receiving a confider- 
 
 able 
 
Earthy Parts of A n i m a l s. 53^ 
 
 dulity of former times celebrated as medicines of extraordinary virtue, and di- Bezoars. 
 ftinguifned by an oriental name, Bezoar, which is laid to fignify a fubduer : w— -v -*—- > 
 of poifons or a lord over poifons ; hence Bezoardic is become a common ap- 
 pellation [in Germany, &c.] for all medicines fuppoled to be poifdled of alexi- 
 pharmac powers. The Bezoar of the Ape, and that of the Porcupine called 
 Piedra del pore 0 have been valued mo ft : Single (tones have been fold for fix ty 
 and eighty pounds fterling. 
 
 There are two Bezoars kept in the (bops, diftinguiflied from the countries 
 whence they are brought, by the names of oriental and occidental. 
 
 THE oriental or beft Bezoar is found in the ftomach of an animal, which Orient aj, 
 is faid to bear a refemblance both to the Goat and the Stag, to the former in Bezoar. 
 the horns, beard, and tail •, to the latter in the body, feet and hair ; called by 
 fome Cervicapra and by others Capricerva , by Ray Gazella indica cornubus redlh 
 longiffmis nigris prope caput tantum annulatis. 1 he animal is deferibed and 
 figured by Kmmpfer, in his Amanitates, and faid to be met with in different 
 parts of Perfia, China and the Eall-Indies. Thole who feed upon mountains, 
 on aromatic herbs, are fuppofed to afford abetter Bezoar than thofe on plains 
 and vallies. 
 
 The Bezoar- ftone is generally obferved to be formed about fome vegetable 
 matter which tire animal has fwallowed, and which is often found in the 
 middle of theftone upon breaking it ; as a bit of draw, wood, ftalk or rind of 
 plants, f£c. This nucleus is gradually covered with fuccdlive incruftations, 
 one over another, which, by conrtant motion in the ftomach are rendered ex- 
 ternally iinootn and poliflied. Such at leaft is the common opinion of the 
 production of Bezoar. 
 
 There 
 
 able pofifa. In either ftate, particularly in 
 the latter, it is difficult of folution even in 
 the ftrong mineral acids. The defirable 
 point, a menftruum that (hall difTolve it and 
 at the fame time be innocent to the body, 
 has hitherto been fought for in vain. 
 
 There are, however, fubftances held to 
 be inoftenfive, which though they do not 
 make a perfect folution of the Calculus, are 
 neverthelefs found to foften and corrode it 
 by degrees into a kind of mucous or pow- 
 dery matter; and which, when freely taken 
 into the ftomach, have feemed to carry 
 their virtue through the organs ofdigeftion, 
 and impregnate the urine with fome degree 
 of this lithontriptic power. 
 
 Such particularly are L'me-water and 
 Sope ; of which the former appears to 
 be the molt efficacious. According to 
 Dr. Whytt’s experiments, the power of 
 Stone-lime-water is near one third greater 
 than that of folutions of Sope in common 
 
 water ; and that of Oyfter and Cockle- (hell 
 Lime-waters, above double to that of Stone- 
 lime-water. Fie finds that the, activity of 
 the Shell-lime-water aifb may be almoft 
 doubled, by pouring upon the calcined 
 (hells a ftrong folution of Sope in (lead of 
 common water. 
 
 Alcaline Ley madecauftic by Quick- lime, 
 and the cauftic volatile fpirits diftilled with. 
 Quick lime from Sal ammoniac or infpif- 
 fated urine, corrode the Calculus very plen- 
 tifully. According to the author above- 
 mentioned, the ftrength of a cauftic Ley, 
 made from only an ounce of Pot-afh and 
 two ounces and a half of Quick-lime to 
 a pound and a half of water, was about fix 
 times greater than that of Oyfter~£helI 
 Lime-water. The plain volatile fpirits are 
 far lefs aftive ; and plain alcaline Ley, 
 though loaded with the Salt, has fcarce any 
 effect at all upon the Calculus. 
 
534 Earthy Parts of Animals. 
 
 Oriental There are Bezoar-ftones of various figures, colours, and magnitudes ; Tome 
 Bezoar. round or oval, others long, flat, kidney- fhaped ; fome compofed of very 
 
 ' *~‘— i thin, and others of thicker incruftations; fome greenifh, verging more or lefs 
 
 to yellow or blackifh, others of a brownifh, greyifh, or blackifh colour with- 
 out any greenness. The largeft are about the fize of a frnall Hen’s egg : 7'he 
 Emperor Rudolphus II. had a Bezoar-ftone larger than a Goofe-egg ; but 
 Boetius de Boot fays it was white and light, and diffolved eafily upon the 
 tongue; from whence it appears plainly not to have been a natural (lone but 
 an artificial compofition. The large, compact, fmooth and fhining ones, are 
 prelerved as curiofities : For medicinal ufe, we mu ft be fatisfied with the 
 fmaller and coarfer •, and even thefe are at prefent fcarcely to be purchafed for 
 money. 
 
 The marks ufually laid down forjudging of the genuinenefs of Bezoar are, 
 that it be of middling fize, about that of a Pigeon’s egg, compact, even, 
 foft or fmooth to the touch, of a fhining furface, and a brownifh, greyifh, or 
 olive colour: That on fucceffively taking off the feveral incruftations, the in- 
 ner ones be all of polifhed furfaces like the outer : That when reduced into 
 
 powder, it appear of a fine green colour: That it have a cavity in the middle, 
 without any vegetable or other matter enclofed : That a red-hot needle do not 
 pierce into it : That it neither gain nor lofe any weight by foaking in warm 
 
 water: That when the moift ftone is rubbed upon dry Time or on a wall 
 white-wafhed with Lime, or the dry ftone rubbed upon moift Lime, it ftain 
 the Lime green; fome make a purple, others a chelhut-brown, and others a 
 yellow ftain, the mark of its genuinenefs : That in like manner it give a green 
 ftain to paper rubbed with Chalk: That it make a ftrong effervefcence with 
 Spirit of Nitre, and tinge the menftruum of a dark red colour: That it do 
 
 not diflolve in Spirit of Wine; and that it be neither very heavy nor very 
 light. Thefe are all the characters of the true natural Bezoar, mentioned 
 by authors, and it w'ere eafy to fhew that they are all imitable by art. 
 
 The Indian writers, and many perlons of good credit who have been in 
 Perfia and the Indies, affirm, that the greater number of Bezoar-ftones are no 
 other than artificial compounds made there ; that fome prepare them from fmall 
 Bezoar ftones reduced into fine powder and made up into a mafs ; but that 
 thefe are very rare, the common ones being made of different ingredients with- 
 out any thing of the true Bezoar. Kaempfer fays, that the genuine Bezoar is 
 in Perfia itfelf fo rare and fo dear, that he cannot believe that a Angle ftone 
 comes into Europe. Many others agree in this account; and indeed the 
 Bezoar-ftone carries in itfelf ftrong marks of art, but hardly any traces of its 
 being formed by nature. 
 
 It is principally in the urinary and gall-bladders, in the kidneys and in the 
 ftomach of animals, that Calculi are produced ; it is very rare to meet with any 
 in the inteftines, the lungs or other parts. The ftones of the kidneys and uri- 
 nary bladder are commonly compofed of different ftrata or incruftations, often 
 fmooth and heavy like mineral ftones, but oftener rough, fpongy, light, and 
 full of inequalities or protuberances : Chemically anaJyfed, or diftilled in an 
 
 open fire, they yield nearly the fame principles as urine itfelf, or at leaft anem- 
 pyreumatic volatile urinous matter : They never have, and cannot have, any 
 
 i vegetable 
 
Earthy Parts of Animals. 
 
 vegetable matter, grafs, pieces of roots, fruits, feeds, iftc. for a nucleus Or 
 
 The gall (tones are commonly yellow, orange-coloured, green, of a blackifh- Be 
 greeniflh-brown, or a colour compofed of green and yellow : They are often ' — * 
 made up of incruftations, feldom compact, but rather brittle and fpongy, and 
 without any foreign matter within : In didillation, they yield the fame princi- 
 ples as gall The balls, or Hones as they are called, formed in the domach, 
 
 confid of fuch matters as the animal has fwallowed, hair, draw, hay, herbs, 
 roots, rinds &c. imperfectly or not at all digefted, and held together by the 
 mucus or flimy juices of the part : Thefe rarely have any incruftations ; ex- 
 ternally they are fometimes fmooth, and fometimes not-, they are ufually the 
 lighted: of all the calculous concretions, and of the ftronged fmell, which in 
 
 fome is offenfive, and in others agreeable When Hones are found in the 
 
 intedines, they generally contain fome indigeded matters, and fmell of the 
 place they were lodged in. 
 
 Now where could the Bezoar-done have been formed ; a done compofed of 
 fuch fine, equal, regular, polifhed incrudations, with a cavity or extraneous 
 body in the middle ? It cannot be produced in parts where thofe bodies do non 
 enter, becaufe they are oftentimes actually found in it : It cannot be produced 
 in thofe parts where they do enter, becaufe then they would be intermixed 
 through its whole fubdance as in the balls found in the domach. How uni- 
 form are all the drata in one Bezoar done! how equal throughout in hardnefs, 
 brightnefs and pcliture! and yet how different are different Hones in ail thefe 
 refpeCts from one another ! Such a regularly-formed concrete is not furely the 
 refult of a fortuitous accumulation and induration of matter tumbling in the 
 paunch of an animal. 
 
 Oriental Bezoar-dones, chemically confidered, may be divided into two 
 claffes ; thofe which are fuppofed to be genuine, and thofe which are acknow- 
 ledged to be counterfeit. T he fird are compounded of Plader-of-Faris, Chalk 
 or other earths, impregnated with a vegetable green tinClure: The latter are 
 made chiefly of refinous fubdances, didinguifhable by their liquefying in the 
 fire, and diffolving in Spirit of Wine. I have examined feveral of both forts, 
 but never could difcover any mark of an animal nature; though an animal 
 fubdance, where or whatfoever it be, cannot efcape difcovery in a chemical 
 enquiry. If fome Hones, however, fhould give out an urinous empyreumatic 
 matter in the fire, it would not follow that they are natural productions, as an 
 animal Glue may be ufed, and according to fome accounts often is ufed for the 
 conglutinating ingredient. 
 
 We may add to the foregoing a third clafs of Bezoars, made up with gums, 
 with extracts, or with infpiffated juices : Thefe are very rare ; they are didin- 
 guifhed by their diffolving in great part in water. I have feen and faded fome 
 of this kind at Frankfort upon the Maine and at Leghorn, but could not pro- 
 cure any for examination. 
 
 A fine, choice oriental Bezoar-done, of the genuine kind (that is, of thofe 
 compounded of earths) being reduced into fine powder, and a fcruple of the 
 powder digefled in a glafs body with a fuitable quantity of rectified Spirit of 
 Wine, the fpirit acquired a greenifh-yellow colour, and on being evaporated, 
 
 left 
 
536 Earthy Parts of Animals. 
 
 Oriental left behind a minute portion, fcarce amounting to one grain, of a blackifti ex- 
 Bezoar. tradt, of no remarkable fmell or tafte. 
 
 On foiling another fcruple of the powder in diftilled water, the event was 
 the fame : The water acquired a green tinge, and left on evaporation, fcarcely 
 one grain of an extradf fimiiar to the former. The powder remaining after the 
 adfion of both liquors appeared unaltered. 
 
 A fcruple of the counterfeit refmous Bezoar digefted in rectified fpirit, 
 yielded feventeen grains of extradf, only three grains remaining undifTolved : 
 The extradf was of a yellowiftmgreen colour, refmous, ftuck to the teeth, tailed 
 bitterilh, and ffnelt difagreeably. 
 
 With water, I could fcarcely get half a grain of extradf from a fcruple of 
 this kind of Bezoar, though the powder was long digefted and boiled in the 
 liquor : The extract had a bitterilh tafte, without any fmell : The refiduum 
 was in fmell, tafte, and colour unaltered. 
 
 T!se powder of the earthy Bezoar was not adted on by Spirit of Vitriol. To 
 Spirit or Nitre, it inftantly communicated a red colour, and raifed an efterve- 
 fcence : The liquor continued of a dark red folong a it was kept in the cold, 
 but on applying heat, it prefently became or a bright yellow, and diffolved all 
 the Bezoar, excepting a very fmall quantity of flaky matter. Spirit of Salt 
 acquired a fine yellow colour, and the undifTolved powder appeared of a greenifh 
 yellow. Spirit of Sal ammoniac extradfed a brownilh-yellow tincture, and left 
 the powder reddifh at top and afh-coloured underneath. Alcaline Ley was 
 tinged of a bright brown; the powder unaltered : Cauftic Ley, of a dark red- 
 difh-brown ; the powder of a Sulphur yellow. 
 
 The refmous Bezoar fwam upon Spirit of Vitriol, like other refmous bodies, 
 and was not fenfibly adted on. About one half of it diffolved in Spirit of 
 Nitre, and tinged the liquor yellowifh, the reft melting together and fwimming 
 on the furface. Spirit of Salt received no colour ; as loon as it was poured on, 
 the powder melted all into one mafs and rofe to the top. In Spirit of Sal am- 
 moniac, it fell to the bottom, unadted on. In alcaline ley, it Boated, and 
 appeared curdly like Sope ; the liquor looked yellowirh. Cauftic ley difloived 
 greateft part of it, and became in like manner fopy, and thick like Muci- 
 lage. 
 
 Two drams of the earthy Bezoar were diftilled in a glafs retort, in a well gra- 
 duated open fire. So long as the heat was continued gentle, the powdered 
 ftone retained its original colour, and the liquid which came over proved co- 
 lourlefs as water. As the heat was increaled, the drops grew yellowifh, and 
 at laft of a deep yellow the powder at the fame time acquiring a Sulphur yel- 
 low colour on the furiace; a little Sublimate of the fame colour arifing into 
 the neck of the retort: There now appeared at the bottom, at one fide, where 
 perhaps the heat was greateft, a confiderable lump of curious faline fpicula, 
 exadfly refembling flowers of Benzoine. When the matter became red-hot, a 
 fmoky vapour arofe, which changed the upper part of the yellow Sublimate to 
 a footy blacknefs. The diftilled liquor amounted in all, to three fcruples and 
 a half ; it had an empyreumatic fmell and tafte, like Spirit of Tartar, without 
 
 any 
 
Bezoar.. 
 
 I — . — »J 
 
 Earthy Parts of A n x m a l s. 537 
 
 any thing of the volatile urinous fmel! produced from animal fubftances. The Oriental 
 yellowifh Sublimate weighed three grains, fmelt like old frnoky tobacco-pipes, 
 and tafted fomewhat faline. The footy Sublimate weighed but one grain-, it 
 was partly fhining, very light, of no fmell or tafte. The Caput mortuum 
 weighed two fcruples fix grains, was very black, light, and had not melted 
 or run together. 
 
 Two drams of the refinous Bezoar being treated in the fame manner, the 
 powder flowed thin in a gentle heat, like Wax or Refin. On increafing the fire 
 there arofe a fcruple of yellowifh empyreumatic liquor, and afterwards a dram 
 and thirty-two grains of a blackifh- brown empyreumatic Oil, in fmell exactly 
 refembling the fetid Oils obtained from other Refins. In the bottom of the 
 retort there remained but eight grains of a black, fpongy, friable coal. 
 
 TH E occidental Bezoar is faid to be found in the ftomach of an animal of Occide 
 the fame genus with that which affords the oriental. This fort of Bezoar is 
 not nearfo beautiful, fo finooth, or fo polifhed as the other : It is commonly 
 
 of a whitifh, afh, or dark- grey colour ; fometimes brownifh or blackifh ; and 
 fometimes of a greenifh-yellow. 
 
 A fcruple of occidental Bezoar, digefted with rectified Spirit of Wine, gave 
 only half a grain of extract, of a yellowifh- green colour, a fomewhat rancid 
 tafte, and no fmell : The remaining powder appeared unaltered. Diftilled wa- 
 ter extracted alfo but half a grain from a fcruple : This extrad was of a 
 ereenifh-brown colour, and had neither tafte nor fmell. 
 
 Spirit of Nitre and Spirit of Sea- fait diffolved greateft part of the Bezoar, and 
 Spirit of Vitriol the whole : All the folutions were yellowifh : From that made 
 in the vitriolic acid, a little cryftalline matter feparated. 
 
 Spirit of Sal ammoniac, common alcaline Ley and cauftic Ley did not dif- 
 folve any fenfible quantity of the powder, but acquired from it a yellowifh 
 tinge the cauftic Ley gained the deepeft yellow. 
 
 On diftilling two drams in an open fire, there arofe twenty-tv/o grains of 
 a brownifh-yellow liquor, of an empyreumatic and fomewhat volatile fmell j 
 on the furface of which fwum two little drops of an empyreumatic Oil : The 
 Caput mortuum weighed one dram and thirty-eight grains ; it was quite 
 black, and continued a fubtile powder like the Bezoar employed. 
 
 From thefe experiments it appears, that the occidental Bezoar is more likely 
 to be an animal production than the oriental, as it yields in diftillation fome 
 fmall portion of volatile urinous matter. It is neverthelefs much inferior in 
 value, as being lefs beautiful, and fcarceiy ever made ufe of in medicine. If 
 the oriental and occidental Bezoars were both genuine, or true animal calculi, 
 they would probably be equal in virtue to one another, though afifuredly not 
 equal to Oyfter-fhefls and other common abforbents. 
 
 CRABS-EYES, improperly fo called, are neither eyes, nor the produce III. 
 of the Crab j but Calculi found in the ftomach of the Craw-fifh or Aftacus fin- Oculi 
 mat Hi s. Cancror. 
 
 The Craw-fifh cafts its fhell every year, and it is only during the little time ^ 
 that the new fhell continues fofc, that the animal can increafe in bulk : As the 
 
 Z z z fhell 
 
Earthy Parts of Animals. 
 
 Oculi (hell hardens and confines the fifh, a white nutritious juice, fecreted in two 
 Cancror. portions of the ftomach, forms by degrees a foft calculous fubftance, of a cru- 
 
 ftaceous texture from fuccefiive appofitions of the juice. Before the calling of 
 the (hell, the (turned animal grows weak and fick, and for fome days lies al- 
 moft dead : It does not take food till fome days after, and in this period, the 
 Calculi feem to ferve for its aliment. Hence we meet with Crabs-eyes (for fo 
 we muft call them "in compliance with cuftom) both in young and in old Crabs 
 before they lofe their (hells, and for a few days afterwards, and not in one or 
 the other for a confiderable time after that period. 
 
 Crabs eyes are of different fizes, hemifpherical or convex on one fide, flat 
 or concave on the other, of a bluifh, white or reddifh-white colour, of a leafy 
 ftruCture, moderately firm and compaCt : There are fmall Arise upon the con- 
 vex part, and irregular impreflions in the concavity. 
 
 Some prefer the blue ftones, taken from the live fifh, on a ridiculous prin- 
 ciple, t at they are impregnated with the animal fpirits, which by boiling are 
 diflipated. Thus much however it is proper to oblerve, that the blue colour is 
 deftroyed by boiling the fiih, and that fait water inclines it more to reddilh than 
 frefh water. They lofe their bluenefs alfo by long keeping. When the bluifh. 
 tinge is fo pale as not to be diftinguifhed in the dry (lone, it becomes percep- 
 tible on pouring hot water upon them; when long kept, they exhibit no blue- 
 nefs either moift or dry. 
 
 Crabs-eyes have been often counterfeited with artificial compofitions of diffe- 
 rent earths, particularly Chalk, Plafter-of-Paris and tobacco-pipe Clay, form- 
 ed in moulds. Thefe are commonly whiter and lighter than the genuine, im- 
 bibe more water, adhere more ftrongly to the tongue, and have lefs diverfity 
 of figures or characters in the concave part. But the more certain criteria are, 
 that they want the leafy texture of the genuine, and are affeCted in a different 
 manner by acids. A counterfeit Crabs-eye, put into diluted Aqua fortis, dif- 
 f'olves either wholly, or by piece-meal, or not at all, whilft the genuine, though 
 great part of it is diffolved, retains its figure, its earthy bafis being extracted 
 by the acid, and the gelatinous conglutinating matter left entire, but porous 
 like a fponge. 
 
 This experiment does not fucceed with undiluted Aqua fortis ; for the con- 
 centrated acid, adting more violently on the (lone, whilft it diflblves the 
 earthy matter, divides and difunites the gelatinous, of which we can now di- 
 ftinguifh only a few flakes. 
 
 The nitrous acid diffolves a larger quantity of Crabs-eyes than any of the 
 others: An ounce of good Spirit of Nitre takes up four drams; the lame 
 quantity of Spirit of Salt, only three drams. The vitriolic acid, whether con- 
 centrated or diluted, diffolves exceeding little ; an ounce either of the Spirit or 
 Oil of Vitriol extracting but five or fix grains. The mild vegetable acids. 
 Vinegar, Lemon-juice, &c. take up about as much. Neither water nor rec- 
 tified fpirit extraCt any thing at all. 
 
 Sixteen ounces of Crabs-eyes, diftilled in an open fire, give over three ounces 
 and a half of liquor, (lightly urinous and empyreumatic : The remaining coal, 
 burnt to white aihes, yields on being elixated with water a fcruple of fixed. 
 Sale 
 
 THE 
 
Earthy Paris of Animals 
 
 J39 
 
 T H E Cuttle-bone, fo called, has nothing of the hardnefs or texture of IV. 
 bones : It is a white brittle fubftance, fo light and fungous that the Dutch call Cuttle- 
 it Z ee-fehuym, Sea-fcum. It is produced on the back of the Cuttle-fifh, and bone. 
 has on its upper furface a cruft harder and more compact than the reft. \ 
 
 The Cuttle-fifh, Sepia , is met with chiefly in the Mediterranean fea, near 
 the fhores : The bone is often thrown on fhore by ftorms, and there picked up •, 
 
 I have feen feveral along the coaft of the Adriatic, in travelling from Loretto 
 by the way of Ancona, Pefaro, Rimini, &c. This fifh is one of thofe, whofe 
 flefli lies bare, without any fkin the others of that clafs are, the Polypus and 
 Loligo. It is furnifhed with a certain liquor of an inky blacknels, which it is 
 faid to throw out upon being purfued, and thus to efcape or conceal itfelf by 
 rendering the water muddy. This liquor, infpiffated, is faid to be the princi- 
 pal ingredient in the Indian ink ufed in drawing. 
 
 Half an ounce of the loft fpongy part of Cuttle-bone, digefted in rectified 
 Spirit of Wine, gave fix grains of extradt, of a fifty fmell, a faline tafte, and 
 cryftalline appearance. Another half ounce, digefted and boiled with water, 
 gave a fcruple of extradt, in colour whitifh-brown, in tafte quite faline. The 
 powder remaining after the addon of both liquors appeared unaltered. 
 
 The powdered bone, fprinkled by little and little into Spirit of Vitriol, to- 
 tally dillolved, and foon cryftallized again upon the furface, without commu- 
 nicating any tinge to the liquor. The nitrous and marine acids likewife to- 
 tally dilfolved it, without receiving any colour. The folution in the marine 
 acid was in tafte extremely bitter: This acid forms indeed a bitter compound 
 with all the animal and other abforbent earths ; but with none fuch an intenfe 
 bitternefs as with Cuttle-bone. Spirit of Sal ammoniac had no effect upon 
 this bone. Common alcaline Ley and cauftic Ley corroded a little ; the firft 
 acquired no tindture, the latter a yellowifh one. 
 
 Two ounces of the powder, diftilled in a glafs retort in an open fire, gave 
 over two drams of an urinous liquor, of a flightly volatile fmell mixed with the 
 common empyreumatic one ; cn its furface there was alfo a little actual empy- 
 reumatic Oil. The Caput mortuum weighed one ounce fix drams. 
 
 I repeated the fame experiments upon the upper hard cruft or lhell. Half 
 an ounce of this yielded with rectified fpirit four grains, and with water a fcruple 
 of extradt : Both the extracts agreed exadtly with thofe made from the fpongy 
 part, except that the watery extradt of thefhell was of a darker brown colour : 
 
 Both the refidua were unchanged. 
 
 The powdered (hell totally diffolved in Spirit of Vitriol, tinged the men- 
 ftruum reddifh, and feparated again in part in a fine white cryftalline form, ft 
 totally diffolved alio in Spirit of Nitre and Spirit of Sea-fair, without imparting 
 any colour. By Spirit of Sal ammoniac, it was nor. fenfibiy adted on. Com- 
 mon alcaline Ley corroded a little into flakes, without acquiring any tinge : 
 
 Cauftic Ley received from it a yellowifh hue, but difeovered no further action. 
 
 On diddling two ounces in an open fire, I obtained four fcruples of urinous 
 liquor, of a volatile empyreumatic fmell, and half a fcruple of empyreumatic 
 Oil the Caput mortuum weighed one ounce fix drams and a half. 
 
 Z Z Z 2 
 
 It 
 
54© Earthy Parts of Animals. 
 
 Cuttle- It appears from this andyfis, that the difference betwixt the two fubftances, 
 bone, in regard to the principles they are compofed of, is not very great : That the 
 
 V— v- — -> fhell contains mod oily matter, and confequently that the fpongy part is the 
 pureft earth and the ftrongeft abforbent. 
 
 This earth is fuppofed to differ, medicinally, from the other animal ab- 
 forbents, in having a mild aftringency. It is fometimes ufed, by thofe who 
 call metals in the imall way, for forming a mould. 
 
 CLASS II. 
 
 Earthy farts of Animals reducible by Fire into Quick-lime. 
 
 Calcareous ^TT^H I S clafs comprehends the {hells of fea- fifties; a fubjedt which, by the 
 v— — v'——' 1 Jl_ multiplicity and diverfity of colours and figures, is both extenfive and 
 delightful to the naturalift, but affords little variety to the chemift. All thefe 
 fubftances confift of the fame calcareous earth, blended with more or lefs of 
 the conglutinating animal principles. They burn into a Quick-lime, more 
 acrimonious* which impregnates water with a greater degree of activity, and 
 which, when tempered into mortar, proves more durable and more compadc 
 than the Limes made from mineral ftones or earths (/). The Dutch have no 
 other Lime for building, than calcined fea-lhells, particularly thofe of Mufcles. 
 
 HALF an ounce of Muscle-shells digefted and boiled in rectified Spirit 
 of Wine, yielded one grain of extradt, which tafted and fmelt rancid. Ano- 
 ther half ounce, treated with water, gave a fcruple of a yellowifh mafs, in 
 tafte faline. The remaining powders had the fame appearance as at firft. 
 
 This fhell totally diffolved in Spirit of Vitriol, tinged it a little yellowifh, 
 and in great part feparated again from the folution in a white cryftalline form. 
 It diffolved totally alfo in Spirit of Nitre, and almoft totally in Spirit of Salt, 
 without giving any colour to either : The fmall matter that was left by the 
 marine fpirit, on being fhaken up, rendered the liquor white, yellow and 
 orange-coloured. Spirit of Sal ammoniac has no effedt. Common Ley eats 
 off a little flaky matter, and acquires a yellowifh tinge : CaufticLey becomes 
 alfo yellowifh, and renders the powder blackifh underneath, and of a fine 
 hoary whitenefs on the upper fur face. 
 
 From 
 
 (f) Shell-Time Jlronger than Stone-lime-wa- 
 ter.'] We have formerly feen that Qyfter- 
 fhell Lime-water adls much more power- 
 fully on the human calculus than that of 
 Stone-lime : Dr. Home informs us from 
 experiment, that it is likewife the moll effi- 
 cacious in the bleaching of linen ; that it 
 whitens more, weakens more, and extracts 
 more out of the cloth ; that it ought to be 
 looked upon as the moll expeditious, but at 
 the fame time the moft dangerous material 
 for bleaching, that is yet known. 
 
 His experiments on this fubjedt afforded 
 
 one remarkable phaenomenon .... Lime 
 and Lime-water preferve many animal fub- 
 ftances in a found entire ftate ; but Lime 
 and alcalies mixed together, yield a Ley 
 which, in regard to animals, is extremely 
 corrofive. The effedts of thefe fubftances 
 on linen are juft the reverfe ; Lime-water 
 being here highly corrofive, and alcalies 
 weakening its power in proportion to their 
 quantity, infomuch that he judges a mixture 
 of one part of Lime with four of pure A1- 
 cali might be ufed in bleaching with fafety.. 
 
Earthy Parts of Animals. 541 
 
 From two ounces, diftilled in a retort, were obtained two fcruples of liquor. Muscle- 
 of a confiderably volatile empyreumadc fmell, with iome drops of adtual Oil shells. 
 fwimming upon it : The Caput mortuum weighed one ounce feven drams and 
 a fcruple. 
 
 Calcined Mufcle-fhells, confidered as a Lime, bind ftrongly and quick. A 
 certain phyftcian prefcribed, in his Majefty’s Apotheca, a draught compofed 
 of calcined Mufcle-fhells, vitriolated Tartar, Syrup of Citron-juice, deception 
 of Hartfhorn, and fome fimple waters. Accordingly the burnt fhells and vi- 
 triolated Tartar were well rubbed together, the Syrup mixed with them, and 
 the decodtion and waters added by degrees: But inftead of forming a liquid 
 mixture, the powder, fo foon as it was moiftened, concreted into a mals of a 
 ftony hardnefs, which required violence to get it out of the mortar. 
 
 OY S T E R-S H E L L S contain lefs oily matter than thofe of Mufcles. Iff 
 Hoffmann reports, that neither one nor the other difcover in diftillation any Ovster- 
 mark of Oil at all ; but the fir ft yield an adtual Oil, and the latter fufficient shells. 
 marks of one. From two ounces of Oyfter-ftiells, cleaned from the outer J 
 
 rough part, there arofe half a dram of liquor, of a (lightly volatile and empy- 
 reumatic fmell : and in the neck of the retort there appeared fome fine oily and 
 faline fcrias. If the quantity of fhells employed, both in Hoffmann’s experi- 
 ment and mine had been larger, we fhould probably have had a more vifible 
 proof that they are not deffitute of Oil. The Caput mortuum was of a footy 
 black colour, and weighed one ounce feven drams and a half. 
 
 Half an ounce of powdered Oyfcer-fhells yielded, with redlified fpirit, one 
 grain of extradf, of a rancid taffe and fmell. From the fame quantity were 
 obtained by water twenty-five grains of a yellowifh mafs, to the taffe quite fa- 
 line. The remaining powders were in appearance unaltered. 
 
 The powdered fhell diflblved totally in all the mineral acids, and communi- 
 cated no colour to any of them •, from the folution made in the vitriolic acid, 
 there feparated a fine white cryffalline matter. Alcaline liquors had no effect, 
 excepting that alcaline Ley feemed to corrode a little of the powder, as it ren- 
 dered it lomewhat flaky. 
 
 THE oriental Pearl-fish has a great affinity with the common Gyfter ; ]jj 
 being a fiattifh bivalvous fhell-fifh, rough on the outfide, generally about the|yf 0XHER „ 
 fame fize, though feme are much larger, and continuing fixed upon the fpot 0 f_p EARLj 
 ■where it is formed. It is flatter than the Oyfter, and the. internal part of the t ,i 
 
 fhell of a fine Pearl colour, with a reddiffi or greenifh caff, or more or lefs of a 
 rainbow appearance. The lower fomewhat concave fhell is more beautiful 
 than the upper flat one; and hence the former is that brought into Europe, for 
 ornamental ufes, under the name of Moiher-of- Pearl, Mater Perlarum. Both 
 this and the common Oyfter- fhell are compofed of ftrata laid regularly on one 
 another; a new incruffation being formed every year on the infide of the fhell. 
 
 It feerns to be one and the fame juice, which regularly fecreted forms the fhell, 
 and which unequally diftributed or ftagnating in particular parts concretes into 
 Pearls; notwithftanding the chemical differences obferved in the two con- 
 cretes. 
 
 3 
 
 Half 
 
54 2 Earthy Parts of Animals. 
 
 Mother- Half an ounce of Mother-of Pearl, reduced into powder, yielded with rec- 
 oI-Pearl. tided Spirit one grain of extraff, of a fifby fmell, and faline tafte, The fame 
 quantity, treated with water, yielded a fcru'ple of extradf, in colour yellowifh- 
 brown, in tafte quite faline. The powders, remaining after the aftion of both 
 menftrua, were of the fame appearance as at firft. 
 
 Saline liquors had the fame action on Mother-of- Pearl as on other fhells. 
 All the mineral acids diffolved it, without receiving any tinge, except that the 
 marine acid left a fmall portion undiffolved, winch when fhaken up into the 
 liquor, appeared compofed of white, yellowifh and reddifh particles floating di- 
 ftindt from one another. Spirit of Sal ammoniac and cauftic Ley had no ef- 
 fect : Plain alcaline Ley corroded a little into flakes, but acquired no colour. 
 
 Two ounces of powdered Mother-of- Pearl being diftilled in aglafs retort in 
 an open fire gradually increafed, there came over two fcruples of an urinous 
 liquor, which fmelt a little volatile and empyreumatic : On its furface were 
 obferved fo me drops of an empyreumatic Oil. The Caput mortuum weighed 
 one ounce feven drams and a fcruple. 
 
 Dr. reports, that if this fhell be laid in whites of eggs well beat up, 
 
 and fet in the fun or in a warm place, and this procefs feveral times repeated, 
 the fhell will become foft enough to receive impreflions ; and that it recovers 
 its hardnefs on being laid in water wherein Tartar has been feveral times boiled. 
 1 have tried the experiment, without being able to fucceed. Perhaps the 
 author has delivered it without having made trial himfelf, or perhaps he has 
 concealed fome particular management that may be neceflary to the fuccefs. 
 
 CLAWS. 
 
 -jY THE black tips of the claws of the common fea Crab, Cancer marinus , 
 
 q , ’ B s _ levigated into a fubtile powder, are frequently employed in medicine as an ab- 
 forbent. Half an ounce of this powder yielded with rectified fpirit two grains 
 of extradf, of a black colour and faline tafte : With water, the fame quantity 
 yielded ten grains, in colour brownifh, in tafte very faline: Both the refidua 
 appeared unaltered. 
 
 Spirit of Vitriol diffolved a confiderable quantity, and cry ftallized as with 
 the other animal earths : Spirit of Nitre and of Sea-falt diffolved nearly the 
 
 whole; and like that of Vitriol, received no colour. Spirit of Sal ammoniac 
 diffolved a little, without acquiring any tinge : Common and cauftic Ley were 
 tinged yellow, without difeovering any remarkable folution. 
 
 Four ounces of the powder, diftilled in an open fire, gave over half an 
 ounce of liquor, of an empyreumatic and flightly volatile fmell, with fome 
 drops of an empyreumatic Oil upon the furface : During the diftillation, there 
 was an appearance of an abtual volatile Salt, but in the progrefs of the opera- 
 tion it was diffolved and waffled down by the liquor. The black Caput mor- 
 tuum weighed three ounces and a half. 
 
 Y TOthisclafs maybe referred the Shells of He-ns-ec-gs, and perhaps 
 
 Egg-shells. thofe of the eggs of other birds. Half an ounce of the Shells of Hens-eggs, 
 cleared from the inner fkin and reduced into powder, yielded with rectified 
 Spirit of Wine, a grain and a half of lol id extract, which in tafte and 
 fmell was quite rancid. From the fame quantity 1 obtained, by means of 
 
 water, 
 
Earthy Parts of Animals. 
 
 water, twenty grains : This extra# appeared of a yellowish colour, and whatEcc- 
 is pretty remarkable, proved faline to thetafte. The remaining powders had ^ — 
 the fame appearance as at firft. 
 
 Among acids, Spirit of Nitre ads upon Egg- fhel Is the mofb powerfully and 
 mod readily. An Egg, laid in Spirit of Nitre, had its fhel 1 entirely eaten off 
 in two hours, the liquor continuing clear. Spirit of Salt like wile diffolves 
 nearly the whole of the (hell, but requires fix or eight hours : The folution is 
 
 colourlefs ; and of a bitter tafte, which thofe made in other acids are not. Spi- 
 rit of Vitriol corrodes, difficultly, nearly all the fhell, and forms with it, as- 
 with the other animal earths, fine cryftalline concretions of a faline appearance, 
 without receiving any tinge. 
 
 Vinegar, diftilled and undiflilled, diffolves the whole in about twelve hours •, 
 the folution is fomewhat flimy and glutinous. The action of the acid may be 
 promoted by cautioufly taking out the Egg from time to time, and fcrapingofF 
 the flimy corroded matter with a fine knife. Towards the end of the procefs, 
 the Egg feems to expand, as if air, or a part of the menftruum had penetrated 
 through the pores of thefkin; or perhaps from the included air dilating itfelf, 
 on the removal of the folid matter which held it in confinement. The Egg 
 thus freed from its fhell is confiderably loft, but does not admit of its figure 
 being much altered, much lefs ot being rolled out fo Gender as to enter a nar- 
 row-mouthed bottle, as reported in books of lecrets r Laid in water, it be- 
 comes a little harder, but is very far from refuming the hardnefs of the fhell 
 which it has loft. 
 
 Solution of Tartar, which diffolves, like other acids, fundry abforbent earths, 
 had no effect on the fhell of an Egg, though digefted with a heat gradually 
 raifed to ebullition. Nor did alcaline liquors, as Spirit of Sal ammoniac, 
 common Ley and cauftic Ley, feem to have the leaft action on it, except that 
 the common Ley eat off a little flaky matter. 
 
 On diftilling two ounces of powdered Egg-ffiells, in a glafs-retort in an 
 open fire, I obtained two fcruples and a half of urinous liquor, which had a 
 volatile empyreumatic finell, with feveral drops of empyreumatic Oil upon the 
 furface ; after this arofe ten grains of volatile Salt, and one ounce feven drams 
 of black coal remained behind in the retort. Hoffmann in his Objervationes 
 j ■phyfico-chemica , and Boeder in his Materia medico, , report, that Egg-ffiells yield 
 an uncommonly large quantity of volatile Salt but ten grains upon two ounces 
 is very far from being a large yield. 
 
 Egg-ffiells are employed by the wine-coopers for curing Wines upon the 
 fret : Added in a fuitable finall quantity, they obtund the acidity, and render the 
 liquor fit for drinking and fufficiently wholfome : An over-proportion occafions* 
 the Wine to grow in a very little time vapid, by ablbrbing pot only the preter- 
 natural acid, but that which is efifential to it as a vinous liquor. For medi- 
 cinal ufe, fome previoufly calcine the fhell : In this ftate, it is more acrid and 
 aftringent than before, and imbibes water more readily and with fome degree 
 of ebullition. Various images and figures are formed of this calx mixed up 
 with ftrong Glue. 
 
 543 
 
 IHHLLSo 
 
 THE. 
 
544 Earthy Parts of Animals, 
 
 T HE. marine produdions, Coral, Coralline, and Sponge, tjfually ranked 
 among vegetables, differ greatly in their chemical analyfis from land-plants 
 and their parts, and agree with fubftances of the animat kingdom (£•). Their 
 prevailing principle is an earth; but to what clafs this earth belongs, has not 
 hitherto been determined. 
 
 I. CORAL, ( Corallum , ccralium , quafi xopy daughter of the fea) is a hard 
 
 Coral, ftony fubftance, refembling in figure the ftem of a plant, divided into branches. 
 
 It is of different colours, black, white, and red : The red is the fort empha- 
 tically called Coral, as being the moft common, and moft valuable, and em- 
 ployed in the way of ornament ; it is of a fine uniform red colour throughout 
 its whole fubftance. 
 
 The greateft quantities of Coral are met with in the Mediterranean fea, as 
 on the coafts of Tufcany, Sicily, Sardinia, Catalonia, Corfica, Majorca, Mi- 
 norca, CM It is fifhed for by means of a large wooden crofs, furnifhed with a 
 weight of Lead in the middle to fink it, and with net-work between the arms, 
 which being drawn by ropes, backwards and forwards among the rocks, en- 
 tangles the Coral : Oftentimes divers are let down, to dired the ends of the 
 arms into cavities of the rocks. 
 
 The Coral is produced upon the rock, and on different extraneous bodies in 
 the fea, and hangs with its branches downwards. It has no appearance of any 
 root like vegetables ; and adheres only fuperficially, to the body on which it 
 is formed, by a bafis which has the exact imprelTion of the part which it ad- 
 heres to ; a mark of its having been, at its firffc formation, in a foft ftate. 
 
 When Coral is newly taken up, the fmall protuberances on its furface are 
 foft, and yield, on being prefied, a milky juice, which effervefces with Spirit 
 of Salt and with Spirit of Nitre, but not with any Alcali. 
 
 Count Marfigli has made fome curious obfervations on this fubjed. 
 Branches of frefh Coral being put into a veffel of fea-water, the protuberances, 
 after Handing for fome time, opened ; and there came forth from each a fine 
 white body, in form of a ftar with eight rays : On taking the fprigs out of the 
 water, thefe white bodies immediately finrunk in again, and in their place ap- 
 peared red protuberances as at firft : On putting the Coral fprigs a fecond time 
 in water, the protuberances opened again, and the white flowers, as he fup- 
 pofes them, [but more probably animalcules of the polypus kind] came forth 
 as before. After thefe bodies had kept expanded in the water for fome days, 
 they contraded into yellow balis, which dropt off and fell to the bottom, and 
 on being opened were found to contain only a glutinous matter, not any fruit 
 or feed as wasexpeded. The cortical part of the Coral had now grown foft, 
 and fell oft in pieces, which formed a foft earth like fine Red-bole. At the 
 fame time, a milky juice, lodged betwixt the cortical part and the inner fub- 
 ftance 
 
 D -Agree animal fubftances.} Some rine polypi. See the late volumes of the 
 
 late obfervations afford reafon to believe, philofophical Tranfadions, and a paper by 
 that thefe bodies are really animal prcduc- Mr. Juffieu in the French Memoirs fur the 
 tions; the work, and the habitation of ma- year 1742. 
 
Earthy Parts of Animals. 545 
 
 ftance of the Coral; was communicated to the water, and made it putrefy ; C o r a l. 
 but in lefs than a month, there appeared upon the furface a white gelatinous f -~~~~v* a **** 
 fkin, about the thicknefs of the back of a knife, and the water recovered its 
 original fmell and take. 
 
 The cortical part which the Coral is all over coated with, is not near lo 
 compact and hard as the internal, and may be eafily taken off whilft frefh; 
 
 The Coral is commonly freed from this bark before it is brought to market. 
 
 The greatek Coral trade is in Genoa and Leghorn. The fmall lprigs, unfit 
 for ornamental ufes, are in the fbops levigated into a fubtile powder, which is 
 given medicinally as an abforbent and mild refcringent. ' 
 
 Coral is not unfrequently imitated by artificial compofitions ; fome of which 
 exactly refemble the natural in weight, hardnefs, politure, colour and appear- 
 ance, are equally reduced, by (having with a knife, into a flefh-coloured 
 powder, make the fame grating noife betwixt the teeth, equally effervefce with 
 Spirit of Nitre, and yield a like yellowifh magma. The abufe is belt difco- 
 vered by fire, the counterfeit not affording the alcaline earth which the genuine 
 Coral does. The colouring ingredients in the artificial maffes are Cinnabar 
 and Minium, both which are eafy to be difcovered. 
 
 The natural Coral feems to receive its colour from Iron ; for Spirit of Vi- 
 triol acquires from it a ferrugineous take; and on calcining the Coral, fome 
 ferrugineous particles are attracted by the magnet from among the afhes. 
 
 Sixteen ounces of Coral, dikilled in an open fire, yield commonly about fix 
 fcruples and a half of a volatile urinous liquor impregnated with volatile alca- 
 line Salt and Oil, together with two or three grains of an actual empyreumatic 
 Oil: From the Caput mortuum, calcined, five fcruples and a half of fixed 
 Salt may be extracted. The quantities of thefe products vary, according as 
 the Coral is frefher, or longer kept : Once I obtained, from fixteen ounces, 
 three drams of urinous fpirit, and three drams of fixed Salt; another time, I 
 got fcarce two fcruples and a half of fpirit, and no Oil, the proportion of fixed 
 Salt being nearly the fame as before. 
 
 The fine red colour of Coral moved the credulity of former times to expedl 
 from it extraordinary medicinal virtues ; and accordingly various folutions, 
 magikeries, Salts, and other preparations have been made from it in this 
 view. The principal aim has been, to extract its colouring matter in the form 
 of fpirituous tindlure : Red tinftures have indeed been prepared with it, but* 
 they owed their colour to the menkruum or to other ingredients ; the colour of 
 the liquor turning out the fame, when white Coral is ufed as when the red, 
 and even when no Coral is ufed at all. 
 
 It is obfervable however that in fome of thefe proceffes the Cora! lofes its 
 colour. One of the tindlures is prepared by diffolving a pound of Sugar in a 
 little water, adding half a pound of Wax, boiling a pound of Coral in this 
 mixture till it lofes its rednefs, and then digeking the Wax and Sugar in Spirit 
 of Wine. The Coral, deprived of its colour by this procefs, is found to be 
 in other refpebts unaltered, and to have lok nothing of its weight. I have not 
 been able to rekoreits colour, by baking it in a loaf of bread, hanging it in a 
 privy, or the other means recommended by authors for recovering and calling 
 forth its latent rednefs. . 
 
 4 A 
 
 Lemery 
 
54-6 Earthy Parts of A n i m a l s. 
 
 Coral. Lemery relates, that by treating red Coral with white Wax, and afterwards 
 — v — — ' digefting the Wax with tartarized Spirit of Wine, he has transferred the tinc- 
 ture of the Coral out of the Wax into the Spirit. On repeating this experi- 
 ment, I obtained no tindfure, but only a quite thick folution of the Wax, 
 though trial was made with both kinds of tartarized Spirit of Wine, that pre- 
 pared by folution, and that by diftillation. 
 
 Among all the tindtures of Coral, Langelott’s (defcribed in the Ephemerides 
 natura curioforwn ) is the mod; remarkable, though it is at the fame time not a 
 little fufpicious. Pieces of red Coral, digefted for a month with a perfedtly 
 white diddled Oil, are faid to have become redder and fofter ; and on continu- 
 ing the heat, to have been refolved into a deep red Mucilage {Mucilago rubicun- 
 dijfima ); the Oil remaining colourlefs, and not mitcible with the Mucilage. 
 This Mucilage, feparated from the Oil, and digefted a little in tartarized Spi- 
 rit of Wine, is faid to have been refolved into a deep red tindlure. 
 
 II. CORALLINE, Corallina, (fo called from its having been fir ft obferved 
 Coralline, upon Coral) is a branched fubftance, refembling iome of the moffes, compofed 
 
 1 - v— of a number of articulations, found adhering to different bodies, in the Medi- 
 terranean and other feas. It is of various colours, redd iff), yellowifh, green, 
 greenifti and whitifb ; among which the green and whitifh are the moll com- 
 mon. It is friable betwixt the fingers, gritty like land betwixt the teeth, of a 
 fomewhat faline tafte, and a ftrong fifhy fmell. Phyficians luppofe it to be 
 anthelmintic. 
 
 Half an ounce of powdered Coralline, boiled with water, gave two fcruples 
 ofextraft; and afterwards with redtified fpirit, ten grains; Spirit, applied at 
 firft, extracted from the fame quantity thirty grains; and water, afterwards, 
 juft as much: The earthy refiduum weighed, in the firft cafe three drams ten 
 grains, in the latter only three drams. Spirit of Nitre diffolved a confiderable 
 portion of the Coralline. On diftillation in an open fire, there arofe an urin- 
 ous and empyreumatic liquor. 
 
 III. SP ONGE is a foft, tough, compreftible fubftance, full of pores, found, 
 Spon g E.i'ke the two foregoing, adhering to different bodies in the fea. It is of vari- 
 
 ous fizes and colours, yellowifh- white, yellow, reddifh-yellow, brown, grey iff-, 
 C pc. The middling pieces, of a yellowifh colour, with fmall pores, free from 
 ftones, {hells, &c. are the beft. 
 
 The great compreffibility of Sponge, and its property of {baking up water, 
 makes it ufeful, mechanically, on many occafions. From the fame property, 
 it is fometimes employed by the furgeons for dilating the orifices of wounds 
 and ulcers : A piece of Sponge, dipt in melted Wax, may be preffed Into a 
 very little cornpafs, and is prevented from expanding again by the induration 
 of the Wax-, a piece thus prepared, put into the orifice, imbibes the moifture 
 of the part, and is proportion ably dilated. 
 
 Burnt Sponge is fometirnes employed in powders for cleaning the teeth, and 
 likev/ife given by phyficians in fcrophulous diforders. It muff be oblerved that 
 in this ftate, it is a fubftance of an entirely different kind from the crude 
 Sponge. Seepage 501. 
 
 Half 
 
Earthy Parts of A N. i m a l s. 547 
 
 Half an ounce of choice Sponge, cut in fmall pieces, being digefted and Sponge, 
 boiled in water, and afterwards in rectified fpirit, the watery decoctions left on 
 being evaporated thirty grains of extract, and the fpirituous three grains ; three 
 drams twenty-feven grains remaining undiffolved. On inverting the order of 
 applying the two menftrua, the proportions turned out fomewhat different : 
 
 For the fame quantity being treated firft with fpirit and then with water, 1 ob- 
 tained of fpirituous extradl five grains, and of watery twenty-five ; the reft- 
 duum weighing three drams and a half. 
 
 The watery extracts tailed faline, and fmelt of the Sponge : The fpirituous 
 had a fweet kind of fmell, and a (lightly faline tafte ; that made by fpirit after 
 water had a degree of bitternefs, which the others difcovered nothing of. In 
 evaporating the tindlure made by fpirit at firft, the matter which the fpirit had 
 diffolved, began to feparate, and formed a yellowiili-green tranfparent (lime 
 upon the furface ; which in the progrefs of the evaporation, fell to the bottom, 
 and conftituted t’neextradl. In diftillation, the fpirit arofe unaltered; but the 
 diddled water had a ftrong fmell like that of fea-weeds or frefh Coralline. 
 
 All the mineral acids totally diffolved Sponge, by the affiftance of a gentle 
 heat, but with different degrees of facility: The nitrous acid diffolved it moil 
 readily, the vitriolic more (lowly, and the marine the mod (lowly of the three. 
 
 Spirit of Sal ammoniac. Oil of Tartar per deliquiurn, and Lime-water, had 
 little or no effect, though the Sponge was boiled with the two laft, for a confi- 
 derable time. 
 
 Sponge, analyfed by fire, gives indubitable proofs of an animal nature, 
 which is much more ftrongly marked in this fubftance than in the Corals or 
 Corallines. Laid on burning coals, it yields the lame fetid fmell that horns, 
 bones or feathers do : Diddled in clofe veffels, by a ftrong fire, it gives over a 
 larger quantity of a concrete volatile Salt, than thofe bodies themfelves, agree- 
 ing in this refpedt with Silk. 
 
 Mr. Geoftroy informs us, in the Memoirs of the French Academy of 
 Sciences, t at fixteen ounces of Sponge were reduced by drying to eleven 
 ounces; that from thefe he obtained one ounce four drams and a half of 
 phlegm, one ounce and a half of urinous fpirit, one ounce four drams and a 
 half of volatile Salt, and half an ounce of empyreumatic Oil ; and that the 
 Caput mortuum, calcined and elixated with water, gave half an ounce of a 
 fixed Salt, not purely alcaline, but of the marine kind. 
 
 Count Marfigli diddled five ounces of Sponge, and obtained from this quan- 
 tity, half an ounce of phlegm, one ounce two drams of firft fpirit, leven drams 
 of a fecond oily fpirit, two drams fen grains of volatile Salt, and thirty-feven 
 grains of fixed Salt : See his Hiftoire phyftque de la mer , Partie iv. 
 
 I fubmitted to the fame operation four ounces of Sponge, well waffled and 
 dried and cut in pieces. There arofe two ounces and a half of liquor phleg- 
 matic and urinous, one dram of empyreumatic Oil, and feven drams of vola- 
 tile Salt. The Caput mortuum, which weighed one ounce fix drams, being- 
 incinerated in the open air, and elixated with water ; the Ley, on (landing for 
 fome time, depofited twenty-feven grains of a cryftalline Salt, and the remain- 
 ing liquor, infpiflated, left eighteen grains more of faline matter. The pure 
 earth weighed two drams two fcruples and five grains. 
 
 4 A 2 
 
 S E C T. 
 
[ 548 ] 
 
 SECT. VII. 
 
 HAIRS, FEATHERS, &c. 
 
 Hair,C?c. ^T^HESE kinds offubftances give out very little to watery or to fpiritu- 
 «_ — ^ | ous menftrua ; but are powerfully afted upon by acid and by alcaline 
 
 liquors aftifted by a boiling heat. Hair diftolves totally in Spirit of 
 Nitre, into a yellow liquor, which if faturated with the Hair, in a boiling heat, 
 depofites a part in cooling, in form of a whitifh mucilaginous fubftance. 
 Cauftic alcaline Ley likewife dififolves, by a boiling heat, Hair, Feathers, and 
 Wool. How thefe bodies may be dyed of a variety of colours, we have for- 
 merly feen under the heads of the colouring materials. I fhall here relate the 
 analytical experiments I have made upon them by fire : The quantity em- 
 
 ployed in each of thefe experiments was fixteen ounces. 
 
 Sixteen ounces of human Hair, diftilled with afire gradually increafed, gave 
 over in all eleven ounces and five drams. On feparating the feveral diftilled 
 matters from one another, I had five ounces fix drams of urinous fpirit; two 
 ounces one dram of volatile Salt ; and three ounces fix drams of empyreumatic 
 Oil. The Caput mortuum weighed four ounces three drams, and on being 
 calcined in an open fire loft five drams : From the white afhes I extradted, by 
 elixation with water, twenty-one grains of a fixed Salt. 
 
 From fixteen ounces of Cows-hair there diftilled eleven ounces and a half : 
 The urinous fpirit weighed feven ounces four drams ; the volatile Salt one 
 ounce fix drams •, and the empyreumatic Oil two ounces two drams. There 
 remained in the bottom of the diftil ling vefiel four ounces four drams of a black 
 coal ; which in calcination to whitenefs loft four drams. From the white calx 
 were extracted twenty- feven grains of faline matter. 
 
 The total of the diftilled matter from Horfes hair was two ounces lefs than 
 from Cows hair. There were of urinous fpirit fix ounces four drams, of con- 
 crete volatile Salt one ounce fix drams, and of empyreumatic Oil one ounce 
 two drams. The Caput mortuum weighed five ounces feven drams, and loft 
 feven drams on being calcined: On elixation it yielded fix grains of fixed fa- 
 
 line matter. 
 
 Hogs briftles yielded more volatile Salt (the mod important product in thefe 
 kinds of experiments) than the Hair of Cows and Horfes, but a little lefs than 
 human Hair. From fixteen ounces there arofe in ail eleven ounces and a half, 
 and the remaining coal weighed four ounces and a half. The urinous fpirit 
 
 amounted 
 
Hairs, Feathers, ©V. 
 
 amounted to feven ounces and a half, and the Salt to two ounces ; the quantity 
 of Oil was the fame with that of the Salt. The Caput mortuum weighed, 
 when calcined to whitenefs, three ounces fix drams ; and gave out to water 
 twenty-four grains of fixed Salt. 
 
 Sheeps Wool gave juft as much volatile Salt as the Hogs Briftles, but a little 
 lefs fpirit, and a little more Oil. The whole of the diftilled matter weighed, 
 as in the former experiment, eleven ounces and a half; the fpirit, feparated 
 from the reft, weighed feven ounces, and the Oil two ounces and a half. The 
 quantity of Caput mortuum was three ounces fix drams, which loft in calcina- 
 tion only two drams. From the calx were obtained by water thirty grains of 
 fixed faline matter. 
 
 Feathers may not improperly be ranked in this clafs of bodies — —The Fea- 
 thers of poultry yielded more volatile Salt than any of the lubftances above- 
 mentioned. From fixteen ounces there arole in all nine ounces and fix drams; 
 from which, by the ufual method of feparation, I had fix ounces two drams of 
 fpirit, two ounces two drams of Salt, and one ounce two drams of Oil. The 
 Caput mortuum weighed fix ounces and a half, and loft in calcination juft an 
 ounce. Twenty-fix grains of faline matter were eiixated from the calx. 
 
 Of all the animal fubftances I have examined, there are very few that yield 
 near fo much volatile Salt as Silk does. From fixteen ounces of Silk there 
 arofe in diftillation nine ounces of mixed matter : On feparating the diftilled 
 matters, I had four ounces two drams of urinous fpirit, three ounces fix drams 
 of volatile Salt, and one ounce of empyreumatic Oil. The Caput mortuum 
 weighed feven ounces, and loft an ounce on being calcined to whitenefs. By 
 elixating the calx, I obtained forty grains of fixed faline matter. 
 
 It may here be obferved, that as all thefe infipid fubftances, poffeffed of no 
 medicinal powers, yield neverthelefs a notable quantity of volatile Salt, and 
 even more than fome of thole that are medicinally the rnoft acftive; it follows, 
 that the theory cannot be juft, wnich makes the medicinal activity of animal 
 matters to depend upon the volatile Salt producible from them, and afcribes 
 particular virtues to particular bodies in confequence of their affording even an 
 mconfiderable quantity of this Salt. If Cochineal for inftance yields a volatile 
 Salt on being analyled by fire, can this be any foundation for its ufe as a me- 
 dicine, when Hair, and Wool, and Feathers, yield twice or thrice as much. 
 
 TO the foregoing analyfes it may be proper to fubjoin that of Leather. 
 The feveral kinds of Leather are the fkins of different animals, differently pre- 
 pared ; macerated for a length of time with Lime and water, to promote the 
 leparation of the Hair or Wool and of the fat and fiefhy parts ; then tanned by 
 maceration with certain aftrin gent fubftances, particularly Oak-bark {h ) ; and 
 
 afterwards 
 
 [h) Tanned by Oak-bark.~\ The ufe of Oak- aftringent quality, by which it contracts 
 bark in tanning depends wholly upon its the fibres of the fkin, makes the texture 
 
 more 
 
Animal Flesh. 
 
 Leather, afterwards fuppled and ftained by oily and certain colouring drugs. Both fkins 
 v — - v — and prepared Leather give out, on being boiled with water, a large quantity of 
 a ftrong Glue ; in which refpedt they differ confiderably from the fubftances 
 above-mentioned, to which, in their analyfis by fire, they bear a great refem- 
 biance. 
 
 From fixteen ounces of cuttings of Leather, there diftilled in all nine ounces 
 and a half : The urinous fpirit weighed fix ounces and a half ; the volatile Salt 
 one ounce fix drams; and the empyreumatic Oil, one ounce two drams. The 
 Caput mortuum weighed five ounces feven drams, and when calcined to white- 
 nefsfive ounces ; the faline matter extracted from it, fix grains. 
 
 SEC T. VIII. 
 
 ANIMAL FLESH. 
 
 T HE nutritious matter of animal Flefh is a lubftance of the gelatinous 
 kind; which water by long boiling diffolves and extradls, from fome 
 forts of Flefh more readily and more completely than from others. If 
 the codtion is performed in dole veffels, and the liquor fkilfully exhaled to a 
 due confidence, it yields a folid extract, which on fome occafions may be a fer- 
 viceable preparation ; as when thoroughly dried it keeps well, and may be 
 again diffolved by warm water into a liquor approaching in quality to a frefh 
 decodtionof the animal fubjedt. 
 
 I analyfed, by diftillation in an open fire, dry Vipers Flefh from Italy, and 
 frefh Beef and Fifh: And to fee how far blood differs from Flefh in the fub- 
 
 ftances into which it is by this procefs refoluble, I made a like analyfis of Ox’s 
 blood ; employing in all thefe experiments, as in thofe of the foregoing fedtion, 
 fixteen ounces of each of the fubjedts. 
 
 Sixteen ounces of dry Vipers gave over in all eight ounces and fix drams : 
 The urinous fpirit weighed four ounces and five drams ; the volatile Salt two 
 ounces two drams ; and the empyreumatic Oil one ounce feven drams. The 
 remaining black coal weighed fix ounces feven drams and a half; and when 
 calcined to whitenefs, fix ounces three drams. From the white calx were ex- 
 traded by water forty-eight grains of fixed Salt. 
 
 The frefh Beef, as containing its native moifcure, yielded a much iarger 
 quantity of phlegmatic fpirit, and a fmaller one of concrete Salt. The whole 
 
 diftilled 
 
 more denfe and clofe, and the Leather of bark : All the vegetable affringents, thkt 
 conlequence lefs pervious to water and more give out their aftringency to water or ftrike 
 durable. There are many other vegetable a black colour with folution of Chalybeate 
 fubftances, which produce the fame effects, Vitriol, are fit for this ufe, more or lefs fo 
 and which might be iubftituted to Oak- in proportion to their degree of aftringency. 
 
A N I M A L F L E S H, ejtjx 
 
 diftilled matter weighed fourteen ounces two drams and a half; of which theF l e s h,- 
 fpirit made up thirteen ounces five drams and a half, the volatile Sait only one — t 
 
 dram, and the empyreumatic Oil four drams. The Caput mortuum weighed 
 one ounce four drams and a half, loft in calcination one dram and a half, and 
 gave out to water eighteen grains of faline matter. 
 
 The total quantity of diftilled matter from the Fifh was exactly the fame as p 
 from the Beef, but the volatile Salt was in larger proportion : Of fpirit I had 1 s H ‘ 
 
 thirteen ounces two drams and a half, of concrete Salt five drams, and of Oil 
 three drams. The Caput mortuum weighed, as that of the Beef, one ounce 
 four drams and a half, and loft a dram and a half in calcination : The faline 
 matter, extracted from the calx by elixation, amounted to twenty- five grains. 
 
 The Ox blood I infpiffated to drynefs, previoufly to the diftillation. Six- 3 L 0 0 D 
 teen ounces of frefh Blood were reduced by the evaporation to three ounces and , _ _ >■ 
 
 a half; and the vapour that exhaled, being caught, was found to be mere 
 water — —The three ounces and a half of dried Blood being committed to di- 
 flillation in an open fire, there arofe two ounces and a half, and one ounce re- 
 mained. Of urinous fpirit I had one ounce, of concrete Salt fix drams, and 
 of Oil fix drams. The Caput mortuum loft in calcination one dram ; and 
 water extradited from the calx ten grains of faline matter (i). 
 
 HUMAN bodies embalmed, called Mummies (a word faid to be of orien- 
 tal origin, and to fignify pijfafphaltum or Bitumen mixed with Pitch) have been 
 
 brought 
 
 Mummy. 
 
 (/) Further experiments on Blood .] Recent 
 Blood is equably fluid, and in tafte fome- 
 what faline. V iewed by a microfcope, it 
 appears compofed of numerous red globules 
 fwimming in a tranfparent fluid. 
 
 On (landing for a little time, it feparates 
 into a thick crajfamentum , and fluid ferum. 
 By agitation, it continues fluid : A con- 
 fiftent polypous matter adheres to the ftir- 
 rer, which by repeated ablution with water, 
 becomes white. 
 
 Received from the vein in warm water, 
 it depofites a quantity of tranfparent fila- 
 mentous matter, the red portion continuing 
 diffolved in the water. On evaporating 
 the fluid, a red powdery fubftance is left. 
 
 It congeals by 'fro ft, and becomes fluid 
 again by warmth : After the liquefadlion it 
 quickly putiefies. Fluid and florid Blood, 
 expofed to a temperate air, putrefies fooner 
 than fuch as is more denfe. 
 
 Infpiffated to drynefs, it leaves a dark- 
 coloured mafs, amounting at a medium to 
 about one fourth the weight of the Blood, of 
 a dark colour, and a bitter faline tafte, eafily 
 inflammable, burning with a bluifh flame. 
 The exuccated Blood is not diifoluble in 
 
 acid or in alcaline liquors, but gives fome 
 tindiure to water and to Spirit of Wine, and 
 is more powerfully added upon by dulcified 
 Spirit of Nitre. 
 
 Recent Blood is coagulated by the mi- 
 neral acids, and by moft of the combinati- 
 ons of them with earthy and metallic bodies. 
 With vegetable acids and with folutions of 
 neutral Salts, it mingles equably without 
 coagulation. Alcalies both fixed and vola- 
 tile, render it more fluid,, and preferve it 
 from coagulating. 
 
 The ferum of Blood is more faline than 
 the crajfamentum , and does not fo fpeedily 
 putrefy. It freezes fomewhat more diffi- 
 cultly than pure water, and its aqueous 
 part evaporates, by a gentle warmth, fome- 
 what more readily, leaving about one 
 twelfth the weight of the ferum of a folid 
 yellowifn pellucid matter. Expofed to a* 
 heat a little greater than that of the human- 
 body, it coagulates into a folid mafs, with- 
 out any coniiderable evaporation. Both 
 this coagulum, and the infpiffated ferum, 
 are readily inflammable in the fire, not dif- 
 foluble in water or in Spirit of Wine, in 
 acid or in alcaline liquors. 
 
55 2 
 
 Mummy. 
 
 ^ — i — 
 
 Jellies. 
 
 Gelatinous Animal Substances. 
 
 brought from Egypt, counterfeited in Europe, and recommended by the fuper- 
 ftition of former times for medicinal ufes. Some dilpenfatories have received 
 Mummy as an officinal-, and many who have difclaimed the ufe of it as a pre- 
 paration of perhaps difeafed human flefh, have neverthelefs been prejudiced in 
 its favour by the balfamic and aromatic ingredients with which it is prepared. 
 How ridiculous a pretence ! Have we not balfams and aromatics in abundance, 
 free from the difguftful mixture which makes, or is fuppofed to make the bafis 
 of Mummy ? And how much more prudent is it to ufe known fubftances, 
 mixed in knov/n proportions, than an unknown medley, of which perhaps we 
 fnall not meet with two parcels alike P 
 
 The Mummy I examined, contained a large proportion of earthy matter, 
 and of a bituminous one of the Afphaltum kind. Four ounces diftiiled in an 
 open fire, yielded three drams of phlegm, two drams and a half of urinous fpi- 
 rit, and at leaft nine drams of a thick Oil of the confidence of balfam : The 
 
 Caput mortuum, calcined and eiixated, yielded one dram of fixed Salt 
 
 From four ounces of the fame Mummy I obtained, by Spirit of Wine, two 
 ounces and two drams of refinous extract: From the remainder I obtained, by 
 water, five fcruplesof a gummy extradf; one ounce and fix drams remaining 
 
 undiflolved Four ounces of the fame Mummy, treated firft with water, 
 
 gave five drams and a fcruple of gummy extradt ; and afterwards with recti- 
 fied fpirit one ounce three drams and a fcruple of a refinous one ; the indiflb- 
 
 luble part amounting to two ounces all but two fcruples Spirit of Wine, 
 
 diftiiled over from the Mummy, received little alteration in its fmell or tafte ; 
 water, a confiderable one. 
 
 SECT. IX. 
 
 Gelatinous Animal Substances. 
 
 T HEfolid parts of animals, whether horny, bony, or earthy, contain 
 more or lels of gelatinous matter *, which is extracted by long boiling 
 in water, and recovered in a folid form by evaporating the decodtion. 
 It is chiefly on this gelatinous principle, that their folidity and firmnefs depend ; 
 for all of them, by the feparation of it, are rendered friable. 
 
 The earthy bodies contain the leaft of this conglutinating matter; the harder 
 bones, more ; and the more flexible horns, more than apy of thefe. The fkins 
 of animals generally contain more than any of the other parts. 
 
 The oily principle of the fubjedt either makes an eflential ingredient in the 
 compofition of the jelly, or is extradted along with it by the water, being by 
 its mediation rendered foluble in water, in the fame manner as the Oils and 
 Refins of vegetables are by their Gums or Mucilages. For the jelly extradted 
 from bones, &c. detonates very ftrongly with Nitre, and yields in diftillation a 
 large quantity of Oil and volatile Salt ; whilft the remaining bone detonates 
 
 very 
 
Gelatinous Animal Substances. 553 
 
 very languidly, and affords little or no Salt or Oil. It feems to be the gela- Jellies. 
 tinous matter, univerfally, that is the direbt matrix or feat of tbofe particles of 
 which the volatile Salt is formed. 
 
 From two ounces of ordinary Glue, that is, the jelly of Mutton bones (£), I 
 obtained, by diftillation in an open fire, two drams of a colourlefs phlegmatic 
 liquor, of a fopy fmell, two drams of a volatile urinous fpirit, and two drams 
 and a half of empyreumatic Oil. 
 
 The Glues or Jellies, extracted from different animal fubftances, differ no- 
 tably fromoneanotner, not only in quantity, but in their degree of tenacity and 
 purity. Thegreateft difference is betwixt thofe of water and of land animals. 
 
 The Glue of fifhes is in general much the hardeft, and lead eafily penetrated 
 by water-, that of many kinds of fea-filhes acquires a hardnefs approaching to 
 that of done. 
 
 THE fine Glue called Ichthyocolla, Ifinglafs, Fifh-glue, is extraded Fish-glue. 
 
 from a large fifh, which is common in the Ruffian feas, and often comes up v — — ^ 
 
 into large rivers, as theWolga, the Danube and others, in Ruffia, Walachia, 
 
 Hungary, fife. Many waggon loads of this fifh are brought to Vienna, in 
 autumn, every Friday afternoon, and fold next morning by the pound. I 
 have never feen any there above nine or ten feet long, though they are com- 
 monly deferibed as being twenty-four feet in length ; nor is the mouth re- 
 markably wide ; nor have they any of the feales reprefented in Pomet’s figure : 
 
 The Cachelot or Spermaceti-Whale of that author refembles them more (ex- 
 cepting in the teeth and the organs for {pouting) than the figure which he gives 
 as that of the Ichthyocolla fifh. They have no bones, nor any griftles, ex- 
 cept a few about the head. 
 
 Ichthyocolla is prepared only in Mufcovy. It is faid to be made from the 
 fkin, tail, fins, flomach, inteftines and bladder of the fifh by boiling or di- 
 gefting them in water, draining off the liquor, evaporating it to a due con- 
 fidence, then pouring the matter upon a plate rubbed with Oil orGreafe to 
 prevent its adhering, and cutting the cake into dices, which are twided or 
 coiled up while foft into different forms, and afterwards thoroughly dried. 
 
 The thin, clear, white pieces are the bed : The large thick ones are commonly 
 moid and fetid in the infide. 
 
 Ichthyocolla diffolves totally in water, excepting a fmall quantity of impure 
 or filamentous matter, which had been cafually mingled or paffed through the 
 coarfe drainer with it. For fome purpofes, it is directed to be diffoived in 
 Spirit of Wine: Rectified fpirit does not a be upon it in the lead; proof-fpirit 
 diffolves it by virtue of its phlegmatic part. 
 
 By 
 
 [k) Glue. J Bones and finews, faid to be begins to grow thick, when it is drained 
 ufed for this purpofe in Germany, France, through bafkets, fuftered to fettle, and then 
 &c. do not afford near fo ftrong a Glue as further evaporated, till on being poured into 
 fluns ; from which laft the Englifh Glue is flat moulds it concretes in cooling into foiid 
 prepared by the tanners. The cuttings -or cakes, which are cut in pieces, and dried 
 parings are fteeped and wafhed with water; on a kind of net. 
 then boiled with frefh water till the liquor 
 
 4 B 
 
554 Gelatinous Animal Substances, 
 
 Fish-glue. By diftillation in an open fire I obtained, from eight ounces of Ichthyocolla, 
 “■*' — " — ' four ounces two drams of urinous fpirit, half an ounce' of concrete volatile 
 Salt, an ounce and a half of empyreumatic Oil, half a fcruple of fixed Salt, 
 and nine drams of earth. 
 
 Ichthyocolla is employed chiefly for ceconomical and mechanic pfes, as a 
 fine Glue, for Mouth-glue, for joining cracked Porcelane and Glafs, for ftif- 
 feningSilk and Gawze, for making artificial Pearls, &c. but more particularly 
 for fining turbid Wines, in which bufinefs the greateft quantities of it are con- 
 fumed. For this purpofe, fome throw an entire piece, about a quarter of an 
 ounce, into a Wine cafk by degrees the Glue diffolves, and forms a fkin upon 
 thefurface, which at length fubfiding, carries down with it the fecujent matter 
 that floated in the Wine : Others previoufly diifolve the Ifinglafs, and having 
 boiled it down to a fiirny confidence, mix it with the liquor, roll the cafk 
 flrongly about, and then fuffer it to (land to fettle. 
 
 That Wines thus clarified, are quite wholefome, is a little queftionable. It 
 is certain, that a portion of the Ifinglafs remains diffolved in them ; and though 
 this fhould feem to be no unfalutary ingredient, as being oftentimes ufed me- 
 dicinally for obtunding and incrafi’ating acrimonious thin humours, and reftrain- 
 ing immoderate excretions, yet it is not perhaps in Wines entirely innocent. I 
 have. been allured by a gentleman of good experience in thefe matters, (Pur- 
 veyor of the cellar to his Britannic Majefty) that Wines fined with Ifinglafs, 
 efpeciaily if drank a little too foon, occafion feveral ill confequences. I was 
 once myfelf, after drinking only a few ounces of Sack which had thus been 
 clarified but had not fettled quite fine, feized in a little time with a ficknefs and 
 vomiting, followed by fuch a vertigo that I could not Hand upright fora mi- 
 nute together j the giddinefs continued, with a naufea and want of appetite, for 
 feveral days. 
 
 Eggs. WHITES of EGGS may be ranked among gelatinous fubftances, as 
 poffefiing their vifcous glutinous quality, fo as to be ufed in cements for 
 Glafs and Earthen-ware, though they differ remarkably from the other bodies 
 of this kind, (at lead, from thofe extracted from the folid parts of animals,) 
 in being not diffolved, but hardened by boiling water. Hence their ufe for 
 clarifying boiling liquors : Beat up into a froth, and mixed with the liquor, 
 
 they unite with and entangle the impure matters that floated in it, and pre- 
 fently growing hard by the heat, carry them up to thefurface in form of fcum 
 no longer diffoluble in the liquid. 
 
 Whites of new laid Eggs, expofed to the fun in dimmer for fome weeks, in 
 a large glafs veffel, gradually loft their fluidity, and became at length quite 
 dry and hard : In this ft ate, they did net ill refemblein colour, confidence and 
 iranfparency, yellowifh gum Arabic or fine Amber: They ftill diffolved in 
 
 cold water, and formed a vifcous fluid as at firfb. Ten drams were reduced by 
 the drying to two drams and a halfj in another trial, the fame quantity weighed 
 when dry two drams tv/o fcrupJes.. 
 
 When the white is hardened by boiling, it ftill lofes a very large proportion, 
 of its weight on being dried : A white of an Egg boiled hard, weighing fix 
 drams twenty-five grains, weighed when dry only fifty-five grains : Another* 
 
 which 
 
Gelatinous Animal Substances, 
 
 which weighed fix drams forty-feven grains, was diminifhed to fifty-two E 
 grains. 
 
 White of Eggs in its liquid Hate, expofed to a gentle warmth, grows by 
 degrees thinner and thinner, in no long time putrefies, and when putrefied 
 greatly refembles urine both in its appearance and qualities. 
 
 When beaten up into froth and buffered to fettle, it divides into two parts ; 
 a thick one which falls to the bottom, and a thin fluid which floats above. 
 
 Mixed with rectified Spirit of Wine, it is coagulated or hardened, nearly in 
 the fame manner as by heat; this effefit lee ms to fucceed beff, when the two 
 liquids are taken in equal quantities. It mingles uniformly with cold water, 
 or fuch as is juft warm ; and with Vinegar and other vegetable acids. 
 
 By the acids of the mineral kingdom it is coagulated, but fomewhat diffe- 
 rently by the different acids. Spirit of Nitre afits on it the raoft powerfully: 
 When gradually mixed with this, it becomes firft white, then of a Sulphur- 
 yellow colour, thickens more and more, fwells up into blifters, and at laft 
 grows quite tenacious and confident, fo as not to run out upon inverting the 
 glafs. With Spirit of Salt, it turns firft white and curdly; on fhaking the 
 mixture, it looks much like fkimmed Milk. Oil of Vitriol renders it fiimy 
 and tenacious ; but on Handing, the mixture grows thin and fluid, and at the 
 fame time yellow. 
 
 Solutions of Alum, white Vitriol, and green Vitriol, mingle equably with 
 white of Eggs, excepting that a very fmall portion of flaky matter feparates : 
 Solution ol blue Vitriol partly coagulates and renders it (limy : By ftrong agita- 
 tion continued for fometime, all thefe mixtures in forne degree coagulate. 
 
 Cauftic Ley mixed with white of Eggs feemed at firft to coagulate it, efpe- 
 cially when the white was previoufly beat up into froth ; but on Handing for a 
 little time, the whole became fluid again. Common Ley and Spirit of Sal 
 ammoniac mingled without coagulation, only a little flaky matter appearing 
 at laft to float about in the liquor. 
 
 Sixteen ounces of whites of Eggs, diftilled in a glafs retort, at firft in a fand- 
 heat and afterwards in an open fire very gradually increafed, gave over thir- 
 teen ounces fix drams and two fcruples of phlegm which had neither frnell nor 
 tafte ; five drams and half a fcruple of a volatile urinous empyreumatic fpirit; 
 three drams of fetid Oil ; and three drams and a half of volatile Salt : The 
 Caput mortuum was black, fpongy, bliftery, and very light, and weighed five 
 drams twenty grains. 
 
 I diftilled alfo in the fame manner two ounces of the whites boiled hard : 
 There arofe two drams and a half of inodorous-and- infipid phlegm, half an 
 ounce of volatile urinous fpirit, thirty-five grains of empyreumatic Oil, and 
 fifteen grains of volatile Salt : The remaining coal weighed two fcruples : The 
 Caput mortuum calcined white, was reduced to an infipid earth, entirely defti- 
 tute of Salt. 
 
 It is obfervable that boiled whites of Eggs partly liquefy on being kept in a 
 moift cellar ; and that powdered Gummy- refins, as Myrrh, inclofed in the 
 white, partly diffclve or deliquiate along with it. 
 
 It is commonly fuppofed, that the pure Refiihs alfo, as Maftich and Ben- 
 zoine, are diffoluble in the fame manner; and feveral preparations of this 
 
 4 B 2 * kind 
 
556 Gelatinous Animal Substances, 
 
 Eggs, kind have been kept in the (hops for medicinal ufe. But experiment has 
 — * — -J (hewn that thefe Oils per deliquium , as they are called, receive no impregnation 
 from the pure Refins-, that when Gummy-refins areufed, it is (Iriblly only the 
 gummy part of the drug that is dilfolved by the aqueous liquid afforded by the 
 Egg-, and that by the mediation of the Gum, a portion of the Refin is ren- 
 dered foluble in this liquid as in common water. All that deliquiates with the 
 white of Egg, will drffolve at leaft equally in fimple water. 
 
 Yolk of YO L KS of Eggs mingle uniformly with water, but on (landing feparate 
 Eggs, again and fall to the bottom: Mixed with Oils, Balfams, Refins, or animal 
 *■— “V— Fats, they render thefe alfo diffoluble in water. 
 
 They contract no union with rectified Spirit of Wine, howevever agitated 
 with it, but are in feme meafure coagulated or thickened. 
 
 Spirit of Vitriol and Spirit of Salt coagulate them into a butyraceous con- 
 fidence-, Spirit of Nitre renders them (limy and gluey ^ Vinegar and alcaline 
 Ley dilfolve or dilute them -, Spirit of Sal ammoniac and caultie Ley thicken 
 them, with this difference, that the mixture with the former grows thinner on 
 (landing, whild that with the latter continues longer thick. 
 
 Yolk of Eggs, dried, does not become tranfparent and horny like the white, 
 but epake and hard : Nor does it lofe near fo much in the exficcation ; a boiled 
 yolk, weighing four drams thirty-fix grains, was reduced only to two drams 
 thirty grains. An expreffed Oil is obtained from the hard-boiled yolks, by 
 beating them fmall, keeping them dirring over a gentle fire till the fuperfiuous 
 humidity is evaporated, and then committing them to a warm prels. 
 
 Sixteen ounces of frefh yolks, diddled in aglais retort with a well graduated 
 fire, gave over five ounces of phlegm which had no fmell or tade, two ounces 
 and a half of a very (lightly empyreumatic phlegm, one ounce fix drams of a 
 volatile empyreumatic fpirit, one dram of a thin empyreumatic Gil, and five 
 ounces half a dram of a thicker, groifer, heavier and darker-coloured Oil t 
 The Caput mortuum was black, compact and ponderous and weighed an 
 ounce and a half. 
 
 From two ounces of yolks boiled hard, there arofe two drams of infipid and 
 inodorous phlegm, feven drams of empyreumatic phlegm, a fcruple of vola- 
 tile fpirit, and five drams ten grains of empyreumatic Oil : The Caput mor- 
 
 tuum weighed a dram and a half, and in appearance refembled the foregoing. 
 In both thefe cJiftill ations, a little volatile Salt begun to concrete about the 
 fides, but the liquor that followed, diffolved and w a fired it down. 
 
 Eggs. OF an Egg which entire weighed 960 grains, the white amounted to 587 
 ^ > grains, the yolk to 249, and the (hell with its fkin to 124 : Of another Egg, 
 
 weighing 1015, the white weighed 640, the yolk 250, and the fhell 125. 
 
 An Egg weighing 800 grains loft, in being boiled hard, 20 grains. In 
 keeping there is alfo a fenfible diminution of weight j a part of the iubflanceof 
 the Egg tranfpiring through the pores of the (hell : When a confiderable va- 
 cuity is thus formed within the (hell, the Egg begins to putrefy. 
 
 Eggs are commonly preferved by packing them up clofe in bran, faw-du(l, 
 or other like fubftances. I kept one in fait- water from May to November ; 
 
 3 and 
 
Gelatinous Animal Substances. 
 
 and notwkhftanding the warmth of the feafon, and that of a fire occafionally, E 
 it continued perfectly fweet; but the yolk was a little harder than that of a u 
 frefh Egg, and the white had received a flight faltifh take, a proof of the 
 porofity of the fhell (/). 
 
 SECT. 
 
 (/) Eggs — perfpiration , &c.] Mr. tie Reau- 
 mur has difcovered that Eggs may be pre- 
 served perfectly fweet for years, ,by rubbing 
 them, as foon as laid, with fats, oils, or 
 other unctuous lubftances, which by pre- 
 venting their perfpiration prevent their cor- 
 ruption. See his Hi/lory of Infers , vol. 2. 
 the Memoirs of the French Academy of Sciences, 
 for the year 1735, and his Practice of the art 
 of hatching and bringing up domejiic Birds. 
 From fome experiments I have made on 
 this fubiedl it appears, that folid fats impede 
 the Perfpiration greatly, but foft Fats and 
 Oils not near fo much. The principal of 
 thefe experiments are as follows, 
 
 New laid Eggs , Perfpired in 
 
 three months. 
 
 Steeped twenty hours in re£li- 
 fied Spirit of Wine, then 
 hung up in a dry room - 
 Kept in bran 
 
 Kept in fand - - - 
 
 Dipt in Oil, and kept in a^ 
 
 Tin-box clofely covered - 3 
 Dipt in melted fat, and kept 
 in bran - 
 
 Kept immerfed in redfified 
 Spirit of Wine - - 
 
 THE author above-mentioned obferves, 
 in his treatifes of hatching and bringing up 
 domeftic fowls, that Eggs perfpire in incu- 
 bation between one fixth and one fifth of 
 their fluid contents ; and thatwhen perfpira- 
 tion is prevented by undtuous fubftances, the 
 Egg produces no embryo, and continues 
 fweet through the whole procefs of incuba- 
 tion. 
 
 It may be added, that too copious a per- 
 fpiration, though the heat be no greater than 
 under the hen, deftroys the embryo ; and 
 that this is the principal caufe of the ill fuc- 
 cefs complained of by thofe who have at- 
 tempted the artificial hatching of birds in 
 England. 
 
 Thofe who have employed for this purpofe 
 ©yens warmed by culinary fire, have been 
 
 folicitous only, with Mr.de Reaumur, about 
 keeping the heat within proper limits, or 
 as nearly as poflible to that of the human 
 body, marked 32 on Reaumur’s thermome- 
 ter, and 95 or 96 on Fahrenheit’s ... I had 
 a fmall oven, fupplied with warm air from 
 an athanor furnace in which a conftant fire 
 was kept up for other purpofes : I contrived 
 for it a regulating thermometer, which, as 
 often as the heat exceeded but a very little 
 that of the human body, ftopt the aperture 
 by which the warm air was admitted ; arid 
 which, as often as the heat fell a little be- 
 low the human, opened it again, fo as to 
 let in more warm air. A more equable or 
 favourable heat could not be wifhed for : 
 The chickens neverthelefs perifhed in the 
 fhell, and not a fingle one lived to the 
 time of hatching. After many fruitlefs re- 
 petitions of the experiment, an excefs of 
 perfpiration occurred as the moll probable 
 caufe of the failure : Accordingly a quan- 
 tity of Eggs was weighed from day to day, 
 both in the oven and under a hen : Thofe 
 in the oven loft daily about T H of their 
 weight, and thofe under the hen only , 3 0 . 
 
 Mr. Cederhielm, (in a paper on the arti- 
 ficial hatching of Eggs, in the Swedifh 
 Tranfadtions for the year 1748) finds that a 
 degree of moifture is neceffary as well as 
 heat. He obferves, that the hen, befides 
 her natural perfpiration, often wafhes her- 
 felf in water, and goes immediately to cover 
 her Eggs. Hence he was led to moiften his 
 egg-boxes every day. 
 
 Reaumur’s principal experiments were 
 made in cafks fet in hot-beds of dung; the 
 egg-bafkets being fupported at proper heights 
 in the cask,* a thermometer placed comrno- 
 dioufly to be confulted from time to time in 
 regard to the heat, and a number of holes 
 made in the cover, to be opened or clofed 
 according to the excefs or deficiency of 
 heat The copious moift, fetid va- 
 
 pours, to which the Eggs are here expofed, 
 prove often fatal to the embryo ; and a good 
 deal of care is requifite to fecure them from 
 thefe vapours. This Mr. Reaumur very 
 
 often 
 
 Nothing. 
 
 557 
 
 G G S. 
 
 — \ 
 
[ 558 ] 
 
 SECT. X. 
 
 Unchious Parts of A N 1 M A L S. 
 
 F a t ^ ^ * 3 an un & uous fubftance, fecreted from the blood, and lodged chiefly 
 
 \ p in the Membrana adipofa. Strong exercife, preternatural heat, an acri- 
 monious ftate of the juices, and other like caufes by which the oily 
 parts of the blood are attenuated, refolved, or evacuated, prevent the genera- 
 tionof fat : Labours of the mind alio have this effect, as well as labour or in- 
 temperature of the body. Hence relt and plentiful food are fufficient to fatten 
 brutes, but in men it is often otherwife. It is furprizing how foon fome birds 
 grow fat; Ortolans in four and twenty hours, and Larks ftill fooner. 
 
 Fats maybe divided, from their confidence, into three kinds; (i.) The 
 foft and thin, which grow perfectly liquid in a very final 1 heat ; (2.) The 
 thick or confiftent, which liquefy lels readily; and (3.) The hard and firm, 
 which require a Fill ftronger heat to melt them. The firft is called Pinguedo ; 
 the fecond Axungia ; and the third Adeps as taken from the animal, and Sebum 
 or Sevum when freed from the fkins, &c. This ufe of the names is not how- 
 ever conftant, fome applying them differently. 
 
 In birds, reptiles, and fifhes (the very large fillies excepted) we find only the 
 firft kind, or the thin fat, in quadrupeds chiefly the twolaft, in fome mcft of 
 the one, and in others of the other. 
 
 A great number of fats have been kept in the fhops, for making ointments, 
 plafters, and other medicinal compolitions ; as Llog’s Lard, the fat of the 
 Boar, the Fox, the Hare, Dog, wild Cat, Alpine Moufe, Beaver; of Hens, 
 Ducks, Geefe, Storks; of the Whale, Pike, -Serpents, Vipers, &c. as alfo 
 human fat. 
 
 Purification. In regard to all thefe kinds of fubftances, much depends upon the manner 
 of purifying or trying, and of keeping them, for they are very apt to fpoil and 
 grow rancid. Diofcorides diredts them to be barely melted in a gentle warmth : 
 Some previoufly wafh them in hot and cold water, or in Wine, but either of 
 thefe liquors do more harm than good. Simple fufion in a w'ater-bath or other 
 gentle heat is fufficient ; the fkins, fibres, and blood-veffels, being previoufly 
 leparated, and the melted? fat further purified by palling through a ftrainer. 
 If any ablution is thought neceffary, rectified Spirit of Wine is the moft pro- 
 per liquor; lor this, if any of it fhould be retained in the fat, will be diffipated 
 in the melting. For the more curious and uncommon fats, the beft way is, 
 to clear them from {kins, &c. then wafh them with rectified fpirit, and keep 
 
 them 
 
 often experienced ; and it is by this he feems of dung, he thought it a grand advantage, 
 to have been miffed. Having fo often feen in ovens warmed by culinary fire, to have 
 the ill effebls of the redundant moift vapours no moifture at all. 
 
UnEtuous Parts of Animals. 55c 
 
 them covered with frefh fpirit, in a clofe veffel, in a cool cellar : A little may Fat. 
 be foon melted, occafionally, in a glafs, and drained off for ufe. u 
 
 Fats taken freely as food, are difficult of digeftion, relax and weaken the 
 tone of the ftomach and inteftines, and are fuppofed likewife to render the 
 juices tenacious, and to increafe Bile. They are ufed in external applications 
 for foftening and fuppling, for abating pains and fpafms, and for promoting, 
 maturation : But it is proper to obferve, that in inflammations, recent wounds, 
 in defenfive plafcers, for varices, or where the bones are carious or laid bare, 
 they do harm. The great number of fats which the flops have bebn accu- 
 ftomed to preferve, do not appear to be all needful: Dr. Cyprianus, who prac- 
 tifed furgery in London, fcarcely employed in his own practice any fats' at ail. 
 
 Formerly human fat was held in great estimation, and incredible virtues 
 wereafcribed to it. Some endeavoured to fubtilize, and prepare a quintelfence 
 from it, by diftillation from bricks, allies, and other additions : Agricola, to 
 make the ingredients more homogeneous, diftils it ’from human bones. When 
 thus iubtilized, it is faid to be of inexpreffible adtivky and penetration, info- 
 much that when rubbed on the palm of the hand, it is felt, in the twinkling of 
 an eye, at the back-bone : So great is the efficacy, of a diftempered imagination. 
 
 T FI O U G H fats differ from one another not a little in their obvious pro- Analyfas of 
 perties, and probably alfo in their medicinal and dietetic qualities; they afford, Fats, 
 upon a chemical analyfis, produdts fimilar in quality, and differing but incon- 
 fiderably in quantity. They all yield a large proportion of Oil, and no volatile 
 Salt ; in which la ft refpedt they differ from the other fuhftances of the animal 
 kingdom. 
 
 T W O ounces of the fat of a Goofe being diftilled in a glafs retort, at firftp A T 0 r a 
 in a fand-heat and afterwards in an open fire; there arofe one dram of a (lightly Goose. 
 empyreumatic liquor, and one ounce fix drams fifty grains of a clear brown 
 coloured Oil of a volatile fmell fomewhat like that of Florfe-radifn. The 
 Caput mortuum was of a fhining black colour, and weighed ten grains. 
 
 Two ounces of Hog’s Lard gave two drams of empyreumatic liquor, and K o g’s 
 one ounce five drams fifty grains of Oil, of the fame volatile fmell with the Lard. 
 foregoing; the Caput mortuum was alfo of the lame black colour, and nf i 
 the fame weight; fo that this fat differs from the foregoing, only in yielding a 
 dram more of empyreumatic liquor or phlegm, and a dram lefs of Oil. 
 
 I examined Lard with different menftrua, as well as by fire ; namely, recfti- 
 fied Spirit of Wine, Water, the acid Spirits of Vitriol, Nitre, and Sea-falt, 
 
 Spirit of Sal ammoniac, common alcaline Ley, and cauftic Ley : None of 
 
 thefe liquors diflolved, or had any effect upon it, in the coid or when affifted by 
 a moderate heat, except that the Spirit of Sal ammoniac feemed, by its turbid- 
 mefs, to have taken up a little of the fat. By boiling, it unites perfectly, like 
 other fats, with cauftic Ley, and forms with it a faponaceous maf's. 
 
 T A L L O W, of common ufe for making Sope 
 as the two foregoing fats, I obtained from two 
 
 and Candles, being diftilled Ta 
 ounces of the Tallow, of 
 empyreumatic 
 
 LLOW. 
 
560 Un&uous _ Paris of Animals. 
 
 Tallow, empyreumatic liquor rwo drams; and of a clear brown Oil, which fmelt like 
 ' Horfe-radifh, one ounce fix drams twelve grains. The remaining coal was 
 of a diming black colour, and weighed eighteen grains. 
 
 Mutton 7’ W O ounces of Mutton-fuet yielded one dram and a half of empyreumatic 
 Suet, liquor, and one ounce fix drams fourteen grains of Oil : The fhining black 
 — v— — ' Caput mortuum weighed fixteen grains. 
 
 Thus we fee how little differences there are even in the proportion of the 
 principles, into which different fats, hard and foft, are relbluble by fire. 
 
 Marrow. THE Marrow of bones differs a little from the dired fats, in its chemical 
 *\ — ■— ' analyfis, as well as in its pleafanter tafte. 
 
 Four ounces of the frefh Marrow of the leg-bone of an Ox, committed to a 
 warm prefs, paffed nearly all through the bag, in form of a fine liquid fat, 
 which hardened in cooling like other fats; only one dram of fine fibres and 
 membranes was left. 
 
 The drained Marrow, digeded in redified Spirit of Wine, differed no change, 
 and communicated nothing to the fpirit : By boiling four drams or the Mar- 
 row in diddled water, and evaporating the decodion, I obtained three grains 
 of an extrad, which had neither tade nor fmell : The three mineral acids, and 
 Spirit of Sal ammoniac, had not the lead adion on it: Strong alcaiine Ley 
 feerned to corrode it a little; and caudic Ley formed with it a confiderably 
 faponaceous compound. In thefe refpeds, it agrees diffidently with other 
 fats: The principal difference is in the didillation. 
 
 Four ounces, diddled in the ufual manner, gave over three drams and a 
 fcruple of a liquor which fmelt like Tallow, two fcruples and a half of a liquor 
 which had more of an empyreumatic and a fouriffi lmell, two ounces and a 
 half of a yellowiffi- brown butyraceous Oil which fmelt like Horfe-radifh, and 
 fix ounces and a half of a blackifh- brown Oil of the fame fmell: The Caput 
 mortuum weighed four fcruples. 
 
 Brains. THE Brains of land animals differ dill more from the dired fats, and 
 — v— — ^ agree nearly with the deffiy parts. They yield in didillation an adual volatile 
 Salt ; and an empyreumatic Oil, fimilar to that obtained from fleffi, bones, dV. 
 without any thing of the peculiar Horfe-radifh fmell of the diddled Oils of fats. 
 
 From fixteen ounces of Oxes brains, cleared as much as poffible from the 
 membranes, there arofe fix ounces two drams two fcruples of a colourlefs phleg- 
 matic liquor, which fmelt nearly like hung beef; four ounces four fcruples of 
 a volatile urinous empyreumatic liquor or fpirit ; and four ounces and a half 
 of empyreumatic Oil. The urinous fpirit yielded on redification two fcruples 
 of a concrete volatile Salt. The Caput mortuum, which weighed one ounce, 
 on being burnt to whitenefs andelixated with water, gave twenty-five grains of 
 fixed Salt, though Hoffmann reports that no fixt Salt is procurable from ani- 
 mal brains. 
 
 Sperma- 
 
 ceti. 
 
 THE brain of a fpecies of Whale, purified from the oily matter, affords a 
 fatofa Angular kind, known in the ffiops by the improper name of Sperma- 
 ceti. The 
 
Unchious Parts of A n i m a l s. ^6r 
 
 The Spermaceti Whale, called Cetus dent at us and Orca, and by the Englifh Sperm a- 
 failors employed in the Greenland-fifhery Trump, Jubart , or Gibbart, is fmaller ceti. 
 than the common Whale, but the head is proportionably much larger, amount- y— 
 ing to above one third the bulk of the whole body. He is furnifhed with teeth,, 
 which the other is not; and wants the flexible bones in the mouth, called 
 Whale bone, which the other has. The throat is alfo remarkably wider. 
 
 One of thele fifties affords fome tuns of brains ; which are firft grofsly freed 
 from the Oil by draining and preffmg, and afterwards more perfedtly purified 
 by fteepingthem in a Ley of alcaline Salt and Quick-lime, which difiolves the 
 remains of the oily matter into a faponaceous liquid. The brains, being then 
 wafhed with water, appear of a Silver whitenefs, and nothing more is required 
 to complete the preparation, than to cut them in fhivers with wooden knives, 
 and fpread them abroad to dry. Such is the Ample procefs, by which this 
 profitable commodity is prepared. It has been faid that Spermaceti is a natural- 
 concrete, found floating on the furface of the northern leas; but this is plainly 
 a falfe report, perhaps calculated to prevent enquiry into the manner of its 
 preparation. 
 
 Good Spermaceti is in fine white flakes, gloffy and fern itranfpa rent, foft and 
 undtuous to the touch, yet dry and eafily friable, in tafte fomewhat like But- 
 ter, of a faint lmell like that of Tallow. 
 
 It is apt in keeping, if not carefully fecured from the air, to grow yellowift, 
 and contradt a rancid fifhy fmelh The more perfectly it has been purified at 
 firft, the lefs fufceptible it is of thefe alterations ; and after it has been fb- 
 changed, it may be rendered white and fweet again, by fteeping it afrefh in a 
 Ley of alcaline Salt and Quick-lime. 
 
 It melts in a fmall degree of heat, and congeals again as it cools. Laid on 
 burning coals, it emits a fetid fmell, like that of the fnuff of a candle. The 
 contadt of flame does not fet it on fire, but wfith a wick it burns equally with 
 common Tallow-candles. 
 
 In diftillation, it totally arifes, leaving no coal or Caput mortuum behind : 
 
 From four ounces were obtained three ounces and a half of Oil, and a dram 
 and a half of phlegm; the other two drams and a half having been wafted or 
 dilTipated in the procefs. The Oil is not a brown or black fetid empyreumatic 
 one, like thofe of other animal lubftances ; but clear, yeilowifti, of a butyra- 
 ceous confiftence, in fmell like Oil of Wax, like which alfo it coagulates in 
 the cold. 
 
 Redtified Spirit of Wine, digefted and boiled with Spermaceti, takes up 
 about half a dram out of half an ounce : Greateft part fettles to the bottom, 
 and the finer particles float in the liquor, in appearance like flowers of Ben- 
 zoine. 
 
 Water, long digefted or boiled with it, extradfs nothing. By grinding it 
 with Sugar or Almonds, it becomes mifcible with water, but not near fo per- 
 fedtly as the vegetable Refins do by the fame treatment ; on Handing for a little 
 time, the Spermaceti feparates and floats on the furface. Yolks of eggs unite 
 it more thoroughly with watery liquors; but when diffolved by thefe alfo \i 
 foon feparates, and falls to the bottom. 
 
 4 C 
 
 Even 
 
5&2 UnEiuous Parts of Animals. 
 
 Sperm a- Even cauflic alcaline Ley does not dilfolve, nor unite with it into Sope, as 
 ceti. it does withal! other fats-, and hence the uie of this Ley in its preparation and 
 v— — ' purification. It mingles fufficiently with Oils, Fats, Balfams, Refins, Butter, 
 Wax, UV. 
 
 Train THE common Whale contains an immenfe quantity of foft fat, which li- 
 O i l. quefies in a gentle warmth : Hence the animal cannot live in feas that are but 
 ^ moderately warm, and is found only in the cold northern ones, about Green- 
 
 land, Iceland, &c. 
 
 Common Train-oil is the fat of the Whale, melted out from the flefby parts. 
 The French extract it in Greenland from the frefh Blubber ; whereas the Eng- 
 li Ha, Dutch, &c. bring home the fifh itfelf, cut in pieces, which putrefying by 
 the length of time, give a more offenfive Oil. 
 
 Sixteen ounces of Train-oil yielded in diftillation an ounce of phlegm, and 
 twelve ounces and a half of empyreumatic Oil : The remaining coal weighed 
 one ounce and a half. 
 
 ODORIFEROUS undluous juices are fecreted in the inguinal region of 
 certain animals, and depofited in particular bags. Civet, ufed in perfumes, 
 is collected betwixt the anus and the organs of generation of a fierce carnivor- 
 ous quadruped, met with in China and the Eaft and Weft-Indies, called a civet 
 Cat, but bearing a greater refemblance to a Fox or a Martin than a Cat. 
 
 Several of thefe animals have been brought into Holland, and afford a con- 
 fiderable branch of commerce, particularly at Amfterdam. The Civet is 
 fqueezed out, in fummer every other day, in winter twice a week-, the quan- 
 tity procured at once is from two fcruples to a dram or more. The juice thus 
 colleded is much purer and finer than that which the animal flieds againft 
 fhrubs or ftones in its native climates. 
 
 Good Civet is of a clear yellowifh or brownifb colour; not fluid, nor hard, 
 but about the confiftence of Butter or Honey, and uniform throughout -, of a 
 very ftrong fmell, quite offenfive when undiluted, but agreeable when only a 
 imall portion of Civet is mixed with a large one of other fubftances. 
 
 This commodity is rarely or never to be met with genuine, notwithftanding 
 the fealed bottles in which it is purchafed at Amfterdam. Nor have we any 
 certain criteria for diftinguifhing its adulteration. Some look upon it as ge- 
 nuine, if when rubbed on paper, it links in, without leaving any thing upon 
 thefurface; and if, when melted in hot water, it totally fwims atop: But 
 
 Lard and Butter, the fubftances principally mixed with it, have both thefe pro- 
 perties, equally with the Civet itfelf. 
 
 Civet unites eaflly with Oils, both exprelfed and diftilled, but not at all with 
 Spirit of Wine, nor with water : Nor is it rendered mifcible with water by the 
 mediation of Sugar. Boeder relates, that Sugar and rectified Spirit are its two 
 beft menftrua -, but he has certainly never made the experiment with either. 
 The yolk of an Eggfeems to difpofe it to unite with water; but in a very little 
 while, the Civet feparates from the liquor and falls to the bottom, though it 
 does not prove of fuch a refinous tenacity as when treated with Sugar and Spi- 
 rit of Wine. 
 
 It 
 
TJnBuous Farts of Animals. 
 
 It communicates however fome fhare of its fmell both to watery and fpiritu-C 
 ous liquors : Hence a fmall portion of it is often added in odoriferous tinctures, 
 and fufpended in the ftil 1-head during the diftillation of odoriferous waters and 
 fpirits j as thofe of Lilies of the valley, Rofes, Rhodium-wood, Orange- 
 flowers, Orange-peel, Yellow-faunders, f jc. The Italians make it an ingre- 
 dient in perfumed Oils, and thus obtain the whole of its fcent; for Oils dlf- 
 folve the whole fubftanceof the Civet. 
 
 MUSK is a concrete juice, collected in a bag, which is fituated under the 
 belly of an oriental quadruped, called by fome a Goat, by others a Stag, but 
 differing confiderably from the animals of both thofe claffes ; for I have feen 
 both the dried fkin and the animal alive. Of all the figures I have met with 
 in books, Pomet’s comes the neareft to it. The Mufk-bag has no external 
 opening like that of the Civet Cat ; and hence the Mufk is not to be got at 
 till the bead is killed. I obferved however, that the apartment in which he 
 was kept, fmelt exceeding ftrongly of Mufk •, and that on the whited walls, 
 where he rubbed himfelf, there was an undtuous matter of the fame fcent. 
 
 Two forts of Mufk are diftinguilhed in trader one inclofed in the bags, and 
 the other taken out of them •, and each of thefe is fubdivided, from the coun- 
 tries whence it is brought, into Tunquin or Eaft-Indian, and Mufcovy or Per- 
 fan Mufk. The Tunquin bags have commonly lmall brownifh hairs-, the 
 Perfian, larger white ones. The former are accounted the belt; but the diffe- 
 rence feems to be only in the quantity, and not in the quality, of the Mufk ; 
 the thinner and lefs hairy ones containing more, in proportion to their weight, 
 than the others. 
 
 As Mufk is one of the deareft of the drugs, it is for the moft part grievoufly 
 adulterated. Some think to avoid being impofed on by buying the entire bags : 
 But the more ingenious artifts have contrived means of opening them, taking 
 out great part of the Mufk, filling them with bafe materials, and clofing 
 them up again fo as not to be diftinguilhed fometimes pieces of Lead are in- 
 troduced, to increafe the weight : Some bags are entirely counterfeit, the bag 
 being made of the fkin of other animals, and its contents only fcented with Mufk. 
 
 Sundry criteria of the genuinenefs of Mufk are mentioned by authors, but 
 as none of them are anywife to be depended on, they need not be enumerated 
 here. The only way of judging whether it is genuine or good, is, to compare 
 it with fpecimens known to be fo. 
 
 With regard to its appearance, it is either of a brownifh-black or a rufty 
 reddifh colour, fometimes clotty like coagulated blood, dry, with a kind of 
 undtuofity to the touch. Its tafte is fomewhat bitterifh ; its fmell extremely 
 ftrong, difagreeable when fmelt near to, or in large quantity, but to moft: 
 people very agreeable at a diftance, or when diluted with a very large admix- 
 ture of other matters. 
 
 Of all the natural fubftances I know, Mufk has the ftrongeft fmell ; and 
 great care is requifite in keeping it, to prevent the diffipation of this vo- 
 latile principle, in which its virtue confifts. The ufual way is, to fecure it 
 in a clofe ftopt glafs ; to inclofe this in a leaden canifter to tie a piece of 
 bladder round the juncture ; and place the whole in a cool dry cellar : Warmth 
 
 4 C a would 
 
564 UnEiuoiis Parts of A N I M A L S. 
 
 Musk, would promote the exhalation, and moifture would occafion the Mufk to fpoil 
 v — — t and grow mouldy. 
 
 The fmell of Mu fie is remarkably diffufive, and remarkably tenacious : 
 Every thing in , its neighbourhood becomes prefently infected with it; andwhac 
 has once received, retains it long : A filver cup, that has had Mufk in ir, does 
 not eafily part with the fcent, though other fmells are in general very readily 
 difcharged from metalline bodies. Some report that Mufk which has loft its 
 fmell recovers it again on being hung in a privy ; and that this is the common 
 practice among the perfumers. 
 
 Thirty grains of Mufk, digefted with water, gave twelve grains of extraft : 
 The fame quantity, treated with rectified fpirit, only ten grains. The Mufk 
 remaining alter the action of water gave out four grains to fpirit; and that re- 
 maining after the action of fpirit gave fix grains to water. 
 
 Spirit of Nitre and Oil of Vitriol totally diifolve it; the former deftroys the 
 whole of its fmell, and the latter greateft part of it. The diluted acid or Spirit 
 of Vitriol has noeffedt; and Spirit of Salt, and diftilled Vinegar fcarcely any. 
 
 Spirit of Sal ammoniac diffolves a little; the dulcified Spirit of Sal ammo- 
 niac, lels. Oil of Tartar per deliquium fcarcely acquires any tinge from the 
 Mufk, but extricates in digeftion a volatile urinous lmell, as if Mufk contained 
 an ammoniacal Salt, whole acid being abforbed by the fixed alcalineLey its 
 volatile Alcali is let at liberty. 
 
 Oils feem to have no adlion on it; for Mufk being triturated with the ex- 
 prefted Oil of Almonds, with the diftilled eflential Oil of Lavender, and with the 
 undiftilled efiential Oil of Citron peel, it did not diftblve, or unite with any 
 of them. 
 
 Laid on a burning coal, it emits the fame fetid fmell as urine does. On di- 
 ftilling a little in a retort, I obtained the fame produdfs as from other animal 
 fubftances, namely an empyreumatic Oil, and a volatile Spirit and Salt. 
 
 The principal ufe of Mufk is as a perfume, for clothes, fcented Sopes, bal- 
 fams, waters, fpirits. Some diredt it in odoriferous compolitions for burning ; 
 but for thefe purpofes it is manifeftly improper, as the fmell which it yields 
 when feton fire is, like that of other animal fubftances, very fetid and offenfive. 
 
 A fmall portion of it, included in a linen-cloth, is commonly hung in the 
 ftill-head, in the diftillation of odoriferous waters and fpirits ; the vapours of 
 both liquors extradling its fcent. If put into the ftill along with fpirit, the 
 fpirit which diftils has nothing, or exceedingly little, of its fcent ; but water di- 
 ftilled over from it in the fame manner, is extremely ftrong both in the fmell 
 nr.d tafte of the Mufk ( m ). 
 
 This drug is fometimes given by phyficians as an antifpafmodic and corro- 
 borant ; but there are many, particularly women, who cannot bear its fmell. 
 
 IN 
 
 [in) Mufk in perfumed waters.] The waters portion of Mufk ; the Mufk, when em- 
 and fpirits, diftilled from odoriferous vege- ployed in very fmall quantity, heightening 
 tables, as Lavender and Rofemary-flowers, the fmell of other odoriferous ingredients, 
 have their fragrance notably improved by without communicating to the compound 
 flcilfully impregnating them with a minute any of its own diftinguiftfimg fmell. 
 
 The 
 
UnBuous Parts of Animals. 
 
 IN the inguinal region of the Beaver are found four oval bags, a large Castor. 
 and a fmall one on each fide. In the two large is contained a foftifh, greyifh- <— » ^ 
 yellow or light brown fubftance •, which, in a warm dry air, grows by degrees 
 hard and brittle, and of a darker and browner colour, efpecially when dried, 
 as it ufually is, in chimneys : This is the Castor of the (hops; when rrefh, it 
 has a very drong, difagreeable fmell, which is greatly weakened by drying. 
 
 The two fmaller bags contain a fofter and more unctuous fat, of the lame kind 
 of fmell with the Cador, and which is ufed by huntfmen (or rubbing on their 
 toils, as a decoy for Foxes, Martins, and other beads of prey, who purfue the 
 Beaver by his fcent. 
 
 The Beaver is an^ nphibious quadruped; in the fore-part like land ani- 
 mals ; the two hindf 0J .eet fomewhat like thofeof water-fowls ; the tail like that 
 of hfhes : lienee v^ome countries the hinder-part is permitted on fall-days, 
 
 and the fore-part forbidden. His habitation is curioufly conftrudted in the 
 banks of rivers or lakes, and divided into dories at diderent heights for retiring 
 to when the water is high or low. He has two kinds of hair, a long coarfe, 
 and a fine diort foft one underneath : The entire fkin is made into muffs, and 
 the lhort hair into hats, &c. 
 
 There are Beavers inPrulda, Mufcovy, Poland, and other parts of Europe, 
 but the greated numbers are in America, particularly Canada. All the Euro- 
 pean Beavers- are of a brown or blackifh-brown colour: Of the American, 
 there are feveral fallow, draw-coloured, and feme quite white. 
 
 It is fuppofed, in Germany, that England produces Beavers ; a fort of Cador 
 being didinguifhed in trade by the name of Englilh Cador. This is not, how- 
 ever, originally an Englirh but an American drug, being brought from Ame- 
 rica into England, and from thence to us. TheEnglifh themfelves rarely 
 make ufe of it, preferring that of Prulda, which they receive from Dantzick. 
 
 The Pruldan is undoubtedly the bed; and next to it is that of Mufcovy. 
 
 The Cador of the full-grown Beaver is fuperior to that of the young; and 
 hence the large cods are to be preferred to the fmall. The bed are moderately 
 heavy, of a blackilh-brown colour, of a drong penetrating fmell, well filled 
 with a brownifh, hard, brittle fubdance, of a naufeous bitterilh talte, inter- 
 mixed with fine fkins or membranes. 
 
 We feldom meet with any confiderable quantity of this commodity free from 
 adulteration. Some open the cods, and having emptied them of their contents, 
 fill them with other matters, and glue up the flit with Ifinglafs fo dextroufly 
 that no mark of it can be perceived. The more fubtile mailers of deceit em- 
 ploy for filling the cods a compofition greatly refembling the Cador itlelf, 
 made of blood, dried and powdered, Gum ammoniacum, Galbanum, Mummy, 
 
 Refin, Wax, £sV. with a little powdered Cador, and the inguinal fat of the ani- 
 mal. 
 
 The bed method of managing it for thefe 
 perfumed liquors feems to be, to make a 
 tinedur'e from the Mufk in reedified Spirit of 
 Wine; and drop this tinedure into the li- 
 quor in fuch quantity as lhall be found ne- 
 ceifary. This appears likewife to be the 
 
 mod certain way of judging of the goodnefs 
 of Mulk ; for the fpirit extraids all its fmell, 
 and the quantity of liquor that may thus be 
 fenfibly impregnated by a certain quantity 
 of Mufk, will bethemeafure of the drength 
 of the Musk, 
 
ALL. 
 
 566 A N I M A L G 
 
 Castor, mal. Some make a imall hole in the lighter cods, and introducing fine fkotor 
 -V'—— ' other ponderous materials, artfully glue it up again. 
 
 An ounce of Caftor digefted with redtified Spirit of Wine, yielded two drams 
 and a fcruple of a tenacious extradl:: Another ounce, treated with water, gave 
 exactly the fame quantity of a brittle extradl:. The Caftor, remaining after 
 the adlion of each of thefe menftrua, being treated with the oppofite one, the 
 quantities now taken up were different; fpirit, applied after water, extracting 
 only a fcruple, and water after fpirit four fcruples. 
 
 The two laft extradts have hardly any fmell or tafle. The extradl made by 
 water at firft retains the ungrateful bitternefs of the Caftor, but has little or no- 
 thing of its fmell, the odoriferous principle arifing with ( .the water in evapora- 
 tion or diftillation : The diftilled water ffnells exceeding S’ ongly of the Caftor, 
 and probably if a large quantity of the drug was fubmitt ^ '"o the operation at 
 once, an adtual effential Oil would be obtained («), though on diftilling a fmall 
 quantity I could not feparate any Oil. Redtified fpirit brings over nothing in 
 diftillation, the fmell as weli as the tafte of the Caftor remaining entire in the 
 extradl;. Hence we learn how unfit this drug is for an ingredient in diftilled 
 fpirits, and in watery extradts ; in both which it is ftill diredted in [foreign] dif- 
 penfatories. 
 
 Caftor has been greatly celebrated by phyficians as an antifpafmodic and 
 antibyfteric medicine ; the ancients accounted it likewile a corredtor of Opium ; 
 perhaps rather from prejudice, than from fair experience of its virtue. When 
 given by itfelf, it is not found to produce any of thole mighty effedts, which 
 have been ufually attributed to it. 
 
 A N 
 
 s 
 
 E C 
 
 T. 
 
 XI. 
 
 M 
 
 A 
 
 L 
 
 GALL 
 
 Gall. A L L or Bile is a bitter fluid, fecreted from the blood in the liver, and 
 
 _ __ 1 I colledted in a particular receptacle ; from whence it is gradually emptied 
 into the alimentary canal, lor promoting the refolution of the aliment 
 and the produdtion of chyle, and for {Emulating the inteftines to difcharge the 
 feces. The Galls of different animals do not feem to differ confiderably from 
 one another : The following experiments were made on that of the Ox. 
 
 GalLftones. THE gall-bladder of an Ox contains commonly from eight to twelve 
 ounces of Gall. There are frequently found in it one or more calculi, fome 
 
 as 
 
 («) Probably would yield an effential Oil . ] Oil 44 is fo fubtile, that a fingle drop re- 
 This fufpicion has been confirmed by ex- “ folved into vapour, is capable of filling a 
 periment, an actual Oil having been ob- “ large extent of air with the fpecific fmell 
 Gained on diftilling large quantities of Caftor 44 of the Caftor.” Fund. Mat. Med. Sefl, 
 at once. Dr. Cartheufer obferves that this xii. cap. 48. 
 
Animal Gall. 567 
 
 as large as a Pigeon’s or fmall Plen’s egg, of a yellow colour like Gamboge, G a l l. 
 and compofed of ftrata or incruftadons like Bezoar ; whence they have been 
 called Bezoar of the Ox. Thefe ftones are partly diflbluble, by the a (lift a nee 
 of a boiling heat, both in water, and in rectified Spirit of Wine. 
 
 The frefhGall is in part yellowifh, in part of a brownifh-greenifh colour, in Mature of 
 confiftence fomewhat thinner than the whites of eggs, of a very bitter tafte,GaU. 
 and little imell. On keeping it grows thicker and more tenacious, at length 
 appears turbid and cloudy, depofites a fediment, and putrefies. 
 
 Gall is fuppofed by fome to be an acid, by others an alcaline, and by others 
 a fopy liquor ; but it does not appear to be any one of thefe. Nothing alcaline 
 can be difcovered in it, till it has undergone the aClion of fire or of putrefaction, 
 by which an alcali is generated in this as in other animal fubftances: And no 
 acid can be dil’covered in it in any ftate. As it contains no alcaline Salt, it 
 cannot be fopy •, for Sope is a combination of alcaline Salt and Oil. Gall is a 
 fluid of a peculiar kind, for we know of no other fubftance in nature that can 
 be ranked in the fame clafs with it. 
 
 Spirit of Vitriol, Oil of Vitriol, Spirit of Nitre, Spirit of Sea-falt, and di- Examined by 
 (tilled Vinegar being dropt into feparate quantities of frefli Gall, each drop coa- acids, GY. 
 gulated the part where it fell, and rendered it thick, tenacious and whitifh (o). 
 
 None of thefe acids occafioned any effervefcence, except the nitrous fpirit; 
 which in a little time after it was added, raifed a flight kind of commotion, 
 with an emiflion of fome vapours. 
 
 It is chiefly from this appearance of effervefcence, with the nitrous acid, 
 falfely extended to the other acids, that Gall has been fuppofed to be alcaline ; 
 but admitting the conflict to be far greater than it is, the conl'equence would 
 by no means be juft: Spirit of Nitre produces a violent ebullition with eflfential 
 Gils, which are fo far from being alcaline, that if they contain any faline mat- 
 ter it is an acid. 
 
 The coagula which Gall forms with the above acids, difiolve on (landing, 
 and at length depofite a little Precipitate, excepting the mixture with the ni- 
 trous acid, which after the reaction is over becomes clear again. 
 
 Oil of Tartar per deiiquium added to Gall, throws down likewife a fmall 
 quantity of coagulated macter. Spirit of Sal ammoniac dilutes or uniformly 
 mingles with it, without occafioning the lead alteration. Rectified Spirit of 
 Wine alfo icarcely makes it cloudy. 
 
 Gall diftilled in the gentle heat of a water-bath, gives over a large quantity By diftilla- 
 of an aqueous fluid. Some report, that when the Gall is previoufly digeftedjtion, 
 the diftilled liquor fmells like Mufk ; and others, that the firft runnings are 
 inflammable: But I have never obferved any degree either of a mufky (cent, or 
 
 of 
 
 (0) Bile with adds, &c.] Though Bile fluid feeming to have very little action upon 
 is oftentimes made whitifh by acids, Ba- the Salt: The Bile neverthelefs had its bit- 
 glivi relates, that human Bile, and that of ternefs increafed by the Alcali to fuch a de- 
 an Ox and a Sheep, were changed by acids gree as to occaiion vomiting on being 
 to a green colour : Hence it is fuppofed that (lightly tailed. Acids on the other hand 
 a green colour of the inteftinal feces proceeds weakened the bitternefs, and volatile fpirits 
 from acid juices mingled with the Bile, rendered it not ungrateful. See Baglivi 
 Salt of Tartar, drope into Bile, remained in Dijfertationes varies, DijJ. iii. dt Bills mtura. 
 great part undifTolved at the bottom, this 
 
5 6S 
 
 Gal 
 
 c 
 
 Its ufes. 
 
 Animal Gall. 
 
 l. of inflammability : When Gall is digefted in a gentle warmth, it begins to 
 — > putrefy, and the liquor that diftils from it is no other than an urinous one, 
 having the common fetid urinous fmell, and changing Syrup of Violets green 
 for though recent animal fubflances require a ftrong fire for generating and 
 extricating an urinous Alcali from them, yet when the Alcali is once produced 
 by putrefaction, it arilts in a gentle heat. 
 
 FreihGall infpiflated and freed from its phlegm in a water-bath, yields on 
 being diftilled in an open fire, an urinous fpirit, a volatile alcaline Salt, and an 
 ernpyreumatic Oil •, and from the Caput mortuum may be obtained a confi- 
 derable proportion of a true fixed alcaline Salt. Eight ounces of Gall yielded 
 fix ounces and a half of phlegm or water, including the phlegm of the fpirit ; 
 half a dram of volatile Salt, including the Salt in the fpirit, and nearly four 
 l'cruples of ernpyreumatic Oil. The Caput mortuum, which weighed two 
 drams and a half, on being urged with a ftronger fire, gave over a little thick 
 oily matter, and a fmall portion of yellow Sublimate : From the reliduum 
 were extradited, by calcination and elixation, twenty-one grains of fixed Alcali 
 the remaining white earth weighed, when dry, one dram and fix grains. 
 
 1 afterwards repeated the experiment with a larger quantity of Gall : From 
 the Galls of feven Oxen I obtained no lefs than half an ounce and a fcruple of 
 pure fixed alcaline Salt ; a produdt the more remarkable, as animal fubflances 
 in general afford exceeding little fixt Alcali, and moft of them fcarcely any 
 at all. 
 
 Ox’s Gall has been made an ingredient in external applications for cutaneous 
 deformities, and fometimes alfo directed by phyficians to be given internally. 
 In the fhops it has been cuftomary to infpiflate the Gall in a water- bath, and then 
 extradt a tindture from it with Spirit of Wine; after the infpiflation it almoft 
 totally diflblves again both in fpirit and in water. 
 
 In France, it is made the bafis of a cofmetic mixture : The ingredients 
 added to it are, Alum,. Sandiver, Porcelane reduced into a fubtile powder, di- 
 ftilled Vinegar, Borax, Spermaceti, Sugar-candy, Camphor, Mercurius dulcis; 
 a ftrange medley of difcordant matters: One of the French academicians, in 
 the Memoirs of the Academy for the year 1709, gives the following prepara- 
 tion of Gall for taking out freckles and lunburn : Sixteen ounces of Ox’s Gall 
 are to be well beat up with half an ounce of powdered Alum, and the mixture 
 fuffered to ftand in the fun for two or three months ; a fediment falls to the 
 bottom, amounting to more than the weight of the Alum employed ; and an 
 undtuousfat matter arifes to the fur face ; from both which the clear reddifh li- 
 quor in the middle is to be ieparated : The cofmetic confifts of one dram of 
 this liquor, the fame quantity of Oil of Tartar per deliquium, and eight drams 
 of river water, with which mixture the part is to be touched feven or eight 
 times a day. 
 
 Un&uous and refinous bodies, triturated with Gall, become foluble in water: 
 Hence Gall is employed in preparing certain fubflances of that clafs for paint- 
 ing in water colours ; for fcouring, taking out fpots, OV. 
 
 1 
 
 SECT. 
 
[ S 6 9 ] 
 
 SECT. XII. 
 
 MILK. 
 
 T he nutritious parts, extracted from vegetable aliments by the powers Milk. 
 
 of digeftion, appear firft in the form of a whitifh liquid called Chyle, * ^ 
 
 which is but little removed from a vegetable nature. On drawing 
 blood from a vein of a healthy animal, four or five hours after feeding, a por- 
 tion of chyle is often found floating on its furface. Soon after this period, the 
 chyle is animalized, and in its place only a thin ferum is to be feen. 
 
 Milk is the chylous part of the blood, fecreted by organs adapted to that its nature and 
 ufe, and fomewhat more afllmilated to an animal nature, but not as yet com- differences, 
 pletelyfoj the fpecific qualities of fundry vegetable fubftances, both alimen- 
 tary and medicinal, remaining unfubdued in the Milk. 
 
 Thus Milk, and the Butter made from it, are found to differ greatly, in co- 
 lour, confidence, tafte and fmell, according to the food of the animal (p). The 
 human Milk is made yellow by taking Saffron, bitter by Wormwood, and im- 
 pregnated with a Garlic fmell by eating that root : A purgative given to a 
 nurfe purges the child at the bread •, and the inebriative power of fermented 
 liquors is in like manner communicated by the Milk. The fweet faccharine 
 fubftance parable from Milk by infpiflfation and cryftallization, and the inflam- 
 mable fpirit by fermentation and diftillation, proceed folely from its vegetable 
 part. 
 
 That it participates alfo of an animal nature, appears from its butyraceous 
 fat matter, and from its analyfis by fire. If retained long in the bread or ud- 
 der, without being recruited by frefh aliment, it changes more and more to an 
 animal date, and becomes a thin, faline, putrid, urinous ferum. The more 
 animal matter is ufed in the food, the more does the Milk participate of the 
 qualities of animal fubdances, and the more it is difpofed to putrefaction. 
 
 The 
 
 (/>) Milk altered by the food .] The Milk of 
 Cows, and the Butter made from it, are ob- 
 ferved to receive an ill flavour from many 
 kinds of vegetables ; from all the plants of 
 the Garlic kind, from many of the umbelli- 
 ferous plants, from the Horfe-mints, Cab- 
 bages, Turneps, autumnal leaves, tiff. This 
 ill tafte may in fbme meafure be diflipated 
 from the Milk by a fcalding heat. 
 
 Dr. Hales has difcovered an ufefu! and 
 fimple method of promoting the diflipation 
 of the more volatile parts of fluids, in a 
 very high degree, by blowing ftreams of 
 
 4 
 
 air through the liquor. Stinking water, by 
 ventilation for a little time, becomes per- 
 fectly fweet and potable ; the air carrying 
 off the offenftve corrupted matter. By the 
 fame means Mijk is effectually freed from 
 its ill fmell, efpecially if made of a fcalding 
 heat whilft the air is blown through it : It 
 
 may be fweetened by ventilation in the 
 cold, but not fo readily nor l'o perfectly as 
 when heat is called in acid. See his 
 Account of a ufeful dijcovery to di/lil double the 
 ufual quantity of fea-watei\ by blowing Jhowers 
 of air up through the dijUlhng liquor. 
 
 D 
 
570 
 
 Milk. 
 
 MILK. 
 
 The Milks of different animals differ, in their perfect date, notably from one 
 , . another. Ic is remarkable of that of the A fs, that it contains more than any 
 
 the 3 Milk* of ot ^ er t ^ iat ^ as ^ een exarr) i nec ^ °f a ferous fluid, and lefs of a butyraceous and 
 different an i_c a feous matter ; an d that when coagulated, the curd is not denfe and heavy, 
 mals. like that of other Milks, but rare and light. 
 
 Hoffmann evaporated eight ounces of Affes Milk by a gentle heat, and had 
 only fix drams remaining, of a whitifh fweet fubdance. He let by twelve 
 ounces in a clofe vefiel, to curdle,; and having feparated and dried the curd, 
 found it to amount fcarcely to two drams, whilft that produced from the fame 
 quantity of Cows Milk weighed ten drams. 
 
 Twelve ounces of Cows Milk fet to evaporate in a tin veffel, left one ounce 
 five drams of a yellow clotty powder: The fame quantity of Goats Milk left 
 one ounce four drams and a half; of human Milk, one ounce ; and of Affes 
 Milk, fcarcely an ounce. 
 
 The powder left in the evaporation by Cows Milk being boiled with twelve 
 ounces of rain water, and the liquor paffed through a drainer, there remained 
 one ounce three drams and a half undiffolved, the water appearing to have dif- 
 folved one dram and a half; on infpiffating the liquor, however, only a dram 
 of folid matter was obtained. The powder of Goats Milk gave out to water 
 the fame proportion ; but that of Affes Milk a much larger one : An ounce of 
 this being digeded with two pounds of water, there remained upon the drainer 
 only a dram and a half, fo that the water had diffolved fix drams and a half, 
 and accordingly upon evaporating the liquor, the refiduum amounted to above 
 fix drams. The fubdance thus extradited by water from infpiffated Affes Milk 
 was white, and of a faccharine fweetnefs ; and that obtained from human Milk 
 was nearly fimilar to it: That of Cows and Goats Milk was not only in lefs 
 quantity, but far lefs fweet. 
 
 I have obtained from Cows Milk a larger proportion of folid matter than 
 Hoffmann did ; a pint, evaporated to drynefs, left two ounces and two drams. 
 The Milk of one and the fame animal is, at different times, very fenflbly diffe» 
 rent in confidence, and confequently in its quantity of folid contents. But it 
 mud be obferved, that though the quantity of folid matter is very variable, 
 that of the faline fubdance which water extradite from it is much lefs fo ; the 
 proportion of this fubdance in Cows Milk never being near fo large, any more 
 than its tade fo fweet, as in Affes and Bread-milk. 
 
 Homberg diddled twelve ounces of Bread-milk in a glafs body, and having 
 drawn over the phlegm by a gentle fire, found ten drams remaining. This 
 refiduum, urged with a dronger heat, gave over two drams and half a fcruple 
 of fetid Oil, and fomewhat more than half an ounce of an acid oily liquor: 
 There was no appearance of any volatile Salt, either in a concrete or liquid 
 form ; but the Caput mortuum, calcined and elixated, gave a fcruple of fixed 
 Alcali, with a dram and a half of a white earth. 
 
 He repeated the experiment with Cows Milk, and found that this contained 
 ids phlegm, and of confequence more folid matter. He obferves that Goats 
 Milk agrees very nearly with that of the Cow ; and that Affes Milk has this 
 remarkable particularity, of yielding a much more fetid fmell in the fire than 
 any of the others. 
 
 Idi- 
 
M I L K. 57 ; 
 
 I diftilled twelve quarts of Milk, in balneo-maria , and obtained at lead nine Milk, 
 quarts of phlegm ; the liquor which now arofe was acidulous, and by degrees \-**~y**=~* 
 grew fenfibly mere and more acid as the diftillation was continued. After this 
 came over a little fpirit, and at laft an empyreumadc Oil. The remaining fo- 
 lid matter adhered to the bottom of the retort in form of elegant fhining black 
 flowers, and feemed in part to have penetrated and united with the Glafs, and 
 changed it into a fubftance refembling Porcelane (q). This refiduum, calcined 
 apd elixated, yielded a portion of alcaline Salt. 
 
 In du Hamel’s Hijloria academia feientiarum , it is faid that the fixed Salt ob- 
 tained from the Caput mortuum of Milk is not alcaline : I am pretty certain 
 that mine was, for it turned Syrup of Violets green, and threw down a raddifh 
 Precipitate from folution of Mercury-fublimate. 
 
 MILK, fet in a warm place, throws up to the furface an undluous creme ; Butts r 
 from which, by agitation, the diredUy undtuous part feparates in the form of » — 
 Butter. 
 
 The addition of alcaline Salts prevents this feparation, not as fome have fup- 
 pofed, by abforbing an acid from the Milk, but by virtue of their property of 
 intimately uniting oily bodies with watery liquors. Sugar, another grand 
 intermedium betwixt Oils and water, has this effedt in a greater degree, though 
 that concrete is by no means alcaline, or an abforbent of acids. 
 
 Butter is not adted upon in the leaft by water, though ftrongly digefted orAnalyfisof 
 boiled with it. Redtified Spirit of Wine extradts a lmall portion, which gives Gutter, 
 no tafte or colour to the fpirit, but difeovers itfelf by rendering the liquor 
 white on the admixture of water. 
 
 From fixteen ounces of frefh Butter, diftilled in a retort, at firft in fand and 
 afterwards in an open fire, there arofe one ounce of liquor of no remarkable 
 fmell or tafte ; one ounce and half a dram of a reddifti acidulous liquor, which 
 fmelt like burnt Butter ; five drams of a brownifh-yellow Oil, three ounces three 
 drams of ajellow Oil, one ounce fix drams of a white, and five ounces and a 
 half of a yellowifh- brown one, all of a thick butyraceous confidence, and a vo- 
 latile fmell like that of Horfe-radifh ; and one ounce fix drams of a thin em- 
 pyreumacic Oil, which fmelt like the Oleum philofophor urn ^ that is Oil Olive di- 
 ftilled over from bricks. There was not the leaft mark of any volatile Alcali 
 in the whole procefs. The Caput mortuum weighed three drams and a half. 
 
 CHEESE is the curd of Milk, prefixed from the whey, and dried : It differs Cheest 
 in quality according as it is made from new or from fkimmed Milk, from the 
 curd which forms fpontaneoufly upon Handing, or that which is more fpeedily 
 
 produced 
 
 (q) Glafs changed into a fubftance like Porce- 
 lane .] Our author appears to be the firft 
 who obferved this extraordinary change of 
 Glafs. ■ It was not owing however, as he 
 feems to imagine, to any particularity of 
 the earthy matter of the Milk ; the fame 
 effeft being produced by all the earthy 
 
 4 D 
 
 bodies I have tried, as Sand, powdered 
 Flint, Plafter-of-Paris, Clay, burnt Clay, 
 &c. and by inflammable bodies, as Soot 
 and Charcoal. Of this remarkable change 
 an account has been already given in 
 page 479. 
 
are 
 
 572 MILK. 
 
 Cheese, produced by certain additions, as the runnet of a Calf. Salt and fpices 
 'w— v - — J often added, and fometimes theCheefe is tinged green, red or yellow, by ve- 
 getable juices. Creme alfo affords a kind of Cheefe, but quite fat and buty- 
 raceous, and which does not long keep. 
 
 Analyfis of An ounce of Cheefe, digefted with water, yielded a dram and a half of ex- 
 Cheefe by tra< cj., which tailed of theCheefe, and had likewife a conliderably faline tafte. 
 mer< ua, Rectified Spirit of Wine extracted very little: During the digeftion with the 
 fpirit, the unCtuous matter of the Cheefe feparated, and arofe to the furface in 
 form of an Oil. 
 
 Spirit of Nitre, digefted with Dutch Cheefe, totally diffolved it into a lim- 
 pid liquor, excepting that a little butyraceous matter floated on the furface, 
 which liquefied on applying heat, and congealed again as it cooled. Spirit of 
 Vitriol diffolved it only in part-, the folution was quite dark- coloured, and 
 threw off an unctuous matter to the top, and fine capillary cryftallizations to 
 the bottom. Spirit of Sea-falt likewife proved only a partial menftruum ; the 
 folution was yellow, and like the two foregoing had an unctuous fubftance on 
 the furface. 
 
 Spirit of Sal ammoniac corroded the Cheefe totally ; and Oil of Tartar per 
 deliquium corroded it partially •, both liquors were turbid, and had an Oil at 
 top. Cauftic alcaline Ley diffolved the whole ; the folution was clear whilft 
 hot, but grew turbid on cooling-, a little powdery matter feparated to the 
 
 bottom, and a very little Oil to the furface It is obfervable that the Cheefe 
 
 funk in Spirit of Salt and in Spirit of Sal ammoniac, but floated upon Spirit of 
 Vitriol, Spirit of Nitre, Oil of Tartar, and cauftic Ley. 
 and by fire. On diftilling in a retort fixteen ounces of Dutch Cheefe, there arofe feven 
 ounces one dram and ten grains of urinous phlegm, two ounces thirty grains 
 of volatile urinous fpirit, fix drams and a half of volatile urinous Salt, and 
 three ounces three drams and a half of empyreumatic Oil : The Caput mor- 
 tuum weighed two ounces fifty grains. 
 
 How different is this analyfis from that of Milk or Butter ! Inftead of a fmall 
 portion of acid which thofe fubftances yield, we have here a large one of vola- 
 tile Alcali ; a mark that the Cheefe has fuffered a degree of putrefaction, or of 
 a procefs analogous to that by which vegetable fubftances are converted into 
 an animal nature. 
 
 Milk. 
 
 Sugar of 
 Milk. 
 
 THE sweet saccharine part of the Milk remains diffolved in the 
 Whey after the feparation of the curd or cheefy matter, and may be collected 
 from it in a white cryftalline form, by boiling the Whey till all remains of the 
 curdled fubftance have fallen to the bottom, then filtering, evaporating it to a 
 due confiftence, fetting it to fhoor, and purifying the cryftals by folution in 
 water and a fecond cryltallization. Much has been faid of the medicinal vir- 
 tues of this Sugar of Milk, but it does not feem to have any confiderable 
 ones : It is from Cows-milk that it has been generally prepared j and the cry- 
 ftals obtained from this kind of Milk have but little fweetnels. 
 
 Whey. 
 
 When Milk is fuffered to coagulate fpontaneoufly, the Whey proves acid, 
 and on Handing grows more and more fa till the putrefactive ftate commences. 
 
 5 Sour 
 
MILK. 573 
 
 Sour whey is ufed as an acid, preferably to the diredlly vegetable or the mine- Milk. 
 
 ral acids, in fome of the chemical arts as for diffolving Iron in order to the ' — J 
 
 ftaining of Linen and Leather (r). 
 
 It is obfervable that Affes-milk is greatly difpofed, on Handing for a little Thick Milk 
 time, to become thick and ropy. In theBreflau colle&ions for the year 1720, 
 there is a remarkable account of Milk (which probably was that of the Afs) 
 grown fo thick and tenacious as to be drawn out into long firings, which when 
 dried were quite brittle (s). 
 
 The 
 
 (r) Sour-milk .] This acid is commonly 
 made ufe of in the bleaching of linen, for 
 diflolving and extra&ing the earthy particles 
 left in the cloth by the alcaline Salts and 
 Lime employed forcleanfing and whitening 
 it. Butter-milk is preferred to plain Sour- 
 milk or Sour-whey : This laft is fuppofed 
 to give the cloth a yellow colour . . . Dr. 
 Home, in his ingenious treatife on this fub- 
 je<St, recommends water acidulated with Spi- 
 rit of Vitriol (in the proportion of about 
 half an ounce, or at moll three quarters of 
 an ounce, to a gallon) as preferable in many 
 refpefts to the acid of Milk, or of the more 
 diredfly vegetable fubftances. He obferves 
 that the latter are often difficultly procur- 
 able, abound with oleaginous particles, and 
 haften to corruption ; whilft the vitriolic 
 acid is cheap, and pure, and indifpofed to 
 putrefy : That Milk takes five days to per- 
 form its office, whilft the vitriolic acid does 
 it in as many hours, perhaps in as many 
 minutes : That this acid contributes alfo to 
 whiten the cloth, and does not make it 
 weaker though the cloth be kept in it for 
 months. He finds that acids as well as al- 
 calies extract an oily matter from the cloth, 
 and lofe their acidity and alcalicity. 
 
 (j) Milk— -thick , tenacious .] New Cows- 
 milk, fuffered to ftand for fome days on the 
 leaves of Butterwort ( Pinguicula ) or Sun- 
 dew, becomes uniformly thick, flippery, and 
 coherent, and of an agreeable fweet tafte, 
 without any feparatioxkpf its parts. Frefti 
 Milk, added to this, is thickened in the 
 fame manner, and this fucceffively. In fome 
 parts of Sweden, as we are informed in the 
 Swedifh Memoirs, Milk is thus prepared for 
 food. 
 
 New Milk has a degree of glutinous 
 quality, fo as to be ufed for joining broken 
 
 ftone-ware. There is a far greater tenacity 
 in cheefe properly prepared. 
 
 Sweet cheefe, fhaved thin, and ftirred 
 with boiling hot water, changes into a tena- 
 cious {lime, which does not mingle with 
 the liquor. Worked with frefh parcels of 
 hot water, and then mixed, upon a hot 
 ftone, with a proper quantity of unflaked 
 Lime, into the confidence of a pafte, it 
 proves a ftrong and durable cement for 
 wood, ftone, earthen-ware and glafs. When 
 thoroughly dry, which it will be in two or 
 three days, it is not in the leaft added upon 
 by water. Cheefe barely beat with Quick- 
 lime, as diredfed by fome of the chemifts 
 for luting cracked glafies, is not near fo te- 
 nacious. 
 
 Cheefe, prepared as above, is recom- 
 mended in the Swedifh Memoirs to be ufed 
 by anglers as a bait. It may be made into 
 any form, is not foftened by the water, and 
 is liked by the fifhes. 
 
 Further experiments on Milk . ] Examined 
 by a microfcope, it appears compofed of 
 numerous globules fvvimming in a tranfpa- 
 rent fluid. 
 
 It boils in nearly the fame degree of heat 
 with common water ; fome forts rather 
 fooner, and fome a little later : After boil- 
 ing, it is lefs difpofed to grow four than in 
 its natural ftate. 
 
 It is coagulated by acids both mineral and 
 vegetable, and by alcalies both fixed and 
 volatile: The coagulum made by acids falls 
 to the bottom of the ferum, that made by 
 alcalies fwims on the lurface, commonly 
 forming, efpecially with volatile alcalies, a 
 thick coriaceous fkin : The ferum, with 
 alcalies, proves green or famous ; with 
 acids, it differs little in appearance from the 
 Whey that feparates fpontaneoufly. The 
 
 coagulum 
 
574 
 
 Animal Excrements. 
 
 Milk. The dietetic ufes of Milk and its produdts are well known. Milk itfelf is 
 v ' one of the molt nutritious and falubrious aliments. Cheefe is a ftrong food, 
 Ufes ofMilk. harc j 0 f digertion. Butter foftens and relaxes, obtunds acrimony, and if taken 
 liberally blunts the adtivity of the gaftric liquor, and weakens the digeftive 
 powers-, Binetus calls it “ Gold in the morning. Silver at noon, and Lead at 
 night.” Where poifonous fubftances, as Arfenic, have been fwallowed. 
 Milk and Butter, taken immediately and in large quantity are the belt remedies 
 for obtunding their force. 
 
 SECT. XIII. 
 
 ANIMAL EXCREMENTS. 
 
 Urine. 
 
 Its remark- 
 able produds. 
 
 f I A H E faline Lixivium, fecreted from the blood in the kidneys and thence 
 conveyed into the bladder, is a liquor of a very lingular kind. That 
 human Urine ftiould participate of the common alimentary Salt, is not 
 extraordinary; but the Urine of brutes, who feed on mere vegetables, contains 
 the fame marine Salt : Whence does it proceed, or from what principle is it 
 produced ! 
 
 Urine contains alfo a peculiar faline fubftance, nowhere difcovered but in 
 Urine itfelf, feparable in a cryftalline form, eafily fufible on a burning coal, 
 and running into a round drop like melted Glafs (/). Diftilled by a ftrong 
 fire, it yields not only the volatile Salt and Spirit, and empyreumatic Oil, 
 common in the animal kingdom, but a peculiar luminous and highly inflam- 
 mable concrete called Phofphorus of Urine. 
 
 There 
 
 coagulum formed by acids is dilTolved by al- 
 calies, and that formed by alcalies is redif- 
 folved by acids ; but the Milk does not in 
 either cafe refume its original properties. 
 
 It is coagulated by moft of the middle 
 Salts, whofe bafis is an earth or a metallic 
 body, as folution of Alum, fixed Sal ammo- 
 niac, Sugar of Lead, green and blue Vi- 
 triol ; but not by the Chalybeate or purg- 
 ing mineral waters, nor by the bitter Salt 
 extracted from the purging waters. 
 
 Among the neutral Salts that have been 
 tried, there is not one that produces any 
 coagulation. They all dilute the Milk, 
 and make it lefs difpofed to coagulate with 
 acids or alcalies : Nitre feems to have this 
 eftedt in a greater degree than the other 
 neutral Salts. 
 
 It is inftantly coagulated by highly recti- 
 fied Spirit of Wine, but fcarcely by a phleg- 
 matic fpirit. 
 
 It does not mingle with exprefied Oils. 
 
 All the coagula are dilTolved by Gall. 
 
 (i) Peculiar Salt from Urine.'] This Salt, 
 called by the chemifts the native , ejjential , or 
 fufible Salt of Urine, or the Microcofmic Salt , 
 is moft commodioufly prepared, by putre- 
 fying a large quantity of Urine, and then 
 flowly evaporating it to the confidence of a 
 thin Syrup ; which being fet in a cold place 
 will yield, in three or four weeks, foul 
 brown-coloured cryftals, containing the mi- 
 crocofmic Salt mixed with the marine or 
 other Salts of the Urine. Thefe cryftals 
 are to be dilTolved in hot water, the folution 
 
 filtered 
 
Animal E : 
 
 filtered whilft it continues hot, and fet to 
 cryftallize again ; and the folution, filtra- 
 tion and cryftallization repeated, till the 
 Salt becomes pure and white : In all the 
 cryftaliizations, the microcofmic Salt Ihoots 
 firft, and is eafily diftinguifhed and feparated 
 from the others. If the Urine which re- 
 mains after the firft cryftallization, be fur- 
 ther evaporated and fet in the cold, it will 
 yield more cryftals, but browner and more 
 impure than the former, and which are 
 therefore to be purified by themfelves. From 
 twenty gallons of Urine may be obtained 
 about four ounces of pure Salt; a confider- 
 able part is ftill left in the thick refiduum. 
 
 In all thefe operations, the heat Ihould be 
 moderate, and the veftels either of glafs or 
 com pa£l ftone ware. The microcofmic Salt 
 is a neutral ammoniacal one, compofed of a 
 peculiar acid united with a volatile Alcali : All 
 other ammoniacal Salts fublime entire on 
 applying heat ; but this fingular Salt parts 
 only with its Alcali, the acid remaining 
 fixed, and incapable of concreting, by itfelf, 
 into a cryftalline form. Having once eva- 
 porated the putrefied Urine by a boiling 
 heat in a copper vefiel, I obtained only a 
 green folution of the Copper in the micro- 
 cofmic acid ; from which I could never 
 afterwards recover the ammoniacal Salt 
 fought for. 
 
 The pure microcofmic Salt impreffes on 
 the tongue a fenfe of coolnefs. It neither 
 deliquiates in a moift air, nor becomes pow- 
 dery in a dry and warm one. Laid upon a 
 burning coal, it does not decrepitate like 
 common Salt, but bubbles and melts 
 like Borax, and runs into a colourlefs pel- 
 lucid fubftance refembling fine Glafs : This 
 apparent glafs difiolves eafily in water, and 
 proves on all trials notably acid ; faturated 
 with volatile Alcali, it cryftallizes into mi- 
 crocofmic Salt again. On mixing either 
 the neutral Salt or the vitreous acid with 
 inflammable fubftances, and diftilling the 
 mixture with a ftrong fire, a phofphorus 
 arifes, fimilar to that obtained direCdy from 
 infpiflated Urine. 
 
 We are obliged to the induftry of Mr. 
 Marggraf for a more particular examination 
 of this very extraordinary Salt. The fub- 
 ftance of his experiments, communicated in 
 the Berlin Memoirs for the year 1746, is as 
 follows. 
 
 Sixteen ounces of die Salt, diftilled in 
 
 i C R E M E N T S. 
 
 a glafs retort, in a fand-heat gradually U 
 railed, gave over eight ounces of a volatile 
 urinous ipirit, refembling that made from Sal 
 ammoniac by Quick-lime. The refiduum 
 was a porous brittle mafs, weighing eight 
 ounces : This, urged with a ftronger fire in 
 a crucible, bubbled and frothed much, and 
 at length funk down into the appearance of 
 Glafs, without feeming to fufter any further 
 diminution of its weight in the molt vehe- 
 ment heat. 
 
 The vitreous matter diffolved in twice or 
 thrice its quantity of water, into a clear 
 tranfparent acid liquor, fomewhat thick, not 
 ill refembling in confiftence concentrated 
 Oil of Vitriol. This liquor totally corroded 
 Zinc into a white powder, which being di- 
 luted with water appeared in great part to 
 to diflolve, fixed alcalies occafioning a plen- 
 tiful precipitation. It a£ted powerfully upon 
 Iron, with fome effervefcence, and changed 
 the metal into a kind of muddy fubftance, 
 inclining to bluilh, in part foluble in water 
 like the preceding. It diflolved likewife a 
 portion of Regulus of Antimoqy, and ex- 
 tracted a red tindure from Cobalt. On 
 Lead and Tin it had very little aCtion : 
 Copper it corroded but flightly: On Bif- 
 muth, Silver, and Gold, it had no efreCt at 
 all, either by ftrong digeftion or a boiling 
 heat. Nor did the addition of a conftder- 
 able portion of nitrous acid enable it to a£t 
 upon Gold. 
 
 The vitreous Salt in its dry form, melted 
 with metallic bodies by a ftrong fire, a£ts 
 upon them more powerfully. In each of 
 the following experiments, two drams of 
 the Salt were taken to two fcruples of the 
 metal reduced into final] parts. (1.) Gold 
 communicated a purple colour to the vitre- 
 ous Salt ; on weighing the metal, however, 
 its diminution was not confiderabie. (2,) 
 Silver loft four grains, or one tenth, and 
 rendered the Salt yellowilh, and moderately 
 opake. (3.) Copper loft only two grains, 
 or one twentieth, though the Salt v/as 
 tinged of a deep green colour. It feemed 
 as if a portion of the Salt had been retained 
 by the metal, which after the fufton was 
 found to be whiter and more brittle than 
 before. (4.) During the fufion with Iron, 
 fiafhes like lightning were continually thrown 
 out, a phofphorus being generated from the 
 combination of the acid of the Salt with the 
 inflammable principle of the Iron. Great 
 
 part 
 
5 7 6 
 
 Urine 
 
 v— ■ 
 
 Animal Ex 
 
 part of the mixture rifes up in Froth, which 
 j when cold appears a vitreous fcoria, covered 
 on the furface with a kind of metallic skin, 
 which on being rubbed changes its green 
 colour to a yellowifh. The reft of the Iron 
 remains at the bottom of the crucible, half 
 melted, half vitrefied, and fpongy. (5.) Tin 
 loft eighteen grains, or near one half its 
 weight, and rendered the Salt whitifh ; the 
 remaining metal being at the fame time re- 
 markably changed. It was all over leafy 
 and brilliant, very brittle, internally like 
 Zinc: Laid on burning coals, it firft begun 
 to melt, and then burnt like Zinc or Phof- 
 phorus. (6.) Lead loft fixteen grains, and 
 gave the fame whitifh colour to the fcoriae 
 that Tin does. The remaining Lead was 
 in like manner inflammable, but burnt lefs 
 vehemently than the Tin ; from which it 
 differed alfo in retaining its malleability. 
 (7.) Mercury precipitated from Aqua fortis 
 and well edulcorated, being treated with the 
 Salt in a glafs retort with a fire raifed to the 
 utmoft, only twelve grains of Mercury fub- 
 limed, twenty-eight remaining united with 
 the Salt into a whitifh femi-opake mafs. A 
 folution of this mixt in diftilled water de- 
 pofited a quantity of a yellowifh powder, 
 which by diftillation in a glafs retort was in 
 great part revived into running Mercury : A 
 part of the Quickfilver remained diffolved 
 alfo in the clear liquor ; for a drop, let fall 
 on polifhed Copper, inftantly whitened it. 
 (8.) Regulus of Antimony, melted with the 
 vitreous Salt, loft eight or nine grains, 
 (about one fifth) : Hie Regulus affirmed a 
 fine brilliant ftriated appearance ; the fcorise 
 were fomewhat opake. (9.) Bifmuth loft 
 eight grains : The fcoriae were like the pre- 
 ceding, but the Bifmuth itfelf fuffered little 
 change, (to.) Zinc mixed with the Salt, 
 and diftilled in a glafs retort, yielded a true 
 Phofphorus, which arole in a very moderate 
 heat. The refiduum was of a grey colour, 
 a little melted at tfie bottom, in weight not 
 exceeding two drams, fo that two fcruples 
 had fublimed. This refiduum, urged iur- 
 ther, in a 1 mall Heffian crucible, to perfedt 
 fufion, emitted an infinity of phofphorine 
 flafhes, with a kind of detonation : T he 
 
 matter, grown cold, looked like the grey 
 fcorise which arife in the fufion of common 
 Glafs. (if.) White Ar fen ic, mixed with 
 this Salt, feparated in the fire, greateft part 
 of it fubliming, and only fo much remaining 
 
 CREMENTS. 
 
 behind as increafed the weight of the Salt 
 eight or ten grains. This compound ap- 
 peared at firft tranfparent, but on beins; ex- 
 pofed to the air became moift, and of an 
 opake whitenefs, much refembling cryftal- 
 line Arfenic. (12.) Cinnabar totally fub- 
 limed, fuffering no change itfelf, and occa- 
 fioning none in the Salt. Sulphur did the 
 fame. (13.) One part of the Salt mixed 
 with ten of Manganefe, and melted in a 
 clofe veffel, gave a femitranfparent mafs, 
 fome parts of which were bluifh. The cru- 
 cible was lined with a fine purple glazing, 
 and the edges of the mafs itfelf appeared of 
 the fame colour. 
 
 The vitreous Salt diffolved alfo, in fufion, 
 metallic calces and earths. Chalk, with 
 one third its weight of the Salt, formed a 
 femitranfparent vitreous mafs : Calcined 
 
 marble, with the fame proportion, flowed fo 
 thin as to run all through the crucible: Gyp- 
 fum likewife run moftly through the cruci- 
 ble; what remained was femitranfparent : 
 Lapis fpecularis ( Marien-glas ) run entirely 
 through the veffel : Spanilh Chalk gave a 
 femitranfparent mafs, which fparkled on 
 breaking; and fine white Clay, a fimilar 
 one : Saxon Topaz and Flint were changed 
 into beautiful opal-coloured maffes ; the 
 earth of Alum into a femitranfparent, and 
 Quick-lime into an opake white one. The 
 mafs with Flints imbibed moifture from the 
 air ; the others not. 
 
 Oil of Vitriol, poured upon one fourth its 
 weight of this Salt in a retort, raifed an ef- 
 fervefcence, acquired a brownilh colour, 
 and afterwards became turbid and white. 
 On raifing the fire, the Oil of Vitriol diftil- 
 led, and the matter in the bottom of the re- 
 tort melted. In the neck was found a little 
 Sublimate, which grew moift in the air ; as 
 did likewife the remaining Salt, which was 
 opake and whitifh— Concentrated fpirit of 
 Nitre, diftilled with this Salt in the above 
 proportion, came over unchanged ; no Sub- 
 limate appeared ; the refiduum looked like 
 Glafs of Borax. The diftilled fpirit did not 
 abt in the leaft upon Gold even by coition — 
 Strong Spirit of Sea-falt being diftilled in 
 the lame manner, no feniible change was 
 made either in the Spirit or the Salt. 
 
 Equal parts of the vitrified microcofmlc 
 Salt and of Salt of Tartar being urged with 
 the ftrongeft fire that a Glafs retort would 
 bear, nothing fenfible came over, nor did 
 
 the 
 
Animal Excrements. 577 
 
 There are confiderable differences in Urine, from the feafon, aliments, or Urine. 
 temperature of the body. It is generally paler and more dilute in winter th ^ n I '^ 7 U 7 ^' 
 
 the mixture appear in thin fufion. Dif- 
 folved in water, filtered, and fuitably eva- 
 porated, it afforded, very difficultly, oblong 
 cryftals, fomewhat alcaline, the quantity of 
 Alcali having been more than enough to fa- 
 turate the microcofmic acid. A whitiffi 
 matter remained on the filter, amounting to 
 feven or eight grains from two drams of the 
 mixture : This, after being wafhed and 
 
 dried, melted before a blow-pipe; as did 
 likewife the cryftals. 
 
 Th is Salt feems to extricate in part the 
 acids of vitriolated Tartar, Nitre, and Sea- 
 falt. ( i.j On diftilling a mixture of it with 
 an equal quantity of vitriolated Tartar, there 
 came over fome ponderous acid drops, which 
 laturated with fixed Alcali formed a neutral 
 Salt greatly refembling the vitriolated Salt. 
 The refiduum readily diflolved in water, 
 and difficultly cryftallized. (2.) Nitre treat- 
 ed with the fame proportion of the Salt be- 
 gun to emit red vapours. The refiduum 
 was of a peach-bloffom colour, appeared to 
 have melted lefs perfectly than the preced- 
 ing, and diffolved more difficultly in water. 
 The folution depofited a little earthy mat- 
 ter, and on being flowly evaporated, fhot 
 into cryftals, which did not deflagrate in the 
 fire. (3.) Sea-falt diftilled in the fame man- 
 ner, manifeftly parted with its acid. The 
 refiduum was whitilh, readily diflolved in 
 water, and afforded fome cubical cryftals. 
 (4.) Sal ammoniac fuffered no change. Bo- 
 rax, with an equal quantity of the vitreous 
 Salt, run all through the crucible. 
 
 Solutions of this Salt precipitated the 
 earthy part of Lime-water, of folution of 
 Alum, of Flint diffolved in fixed Alcali, 
 and the liquamen falis ammoniaci Jjxi, or con- 
 centrated folution of Chalk or Quick-lime 
 in the marine acid. The Precipitate ob- 
 tained from this laft liquor is tenacious like 
 Glue, and does not diffolve even in boiling 
 water : Expofed to a ftrong fire, it froths 
 prodigioufly, and at laft melts into a thick 
 icoria. 
 
 Solutions of this Salt precipitate alfo fun- 
 dry metallic folutions, as Butter of Anti- 
 mony ; folutions of Silver, Copper, Lead, 
 Iron, Mercury, and Bifmuth, in the nitrous 
 acid ; and of Tin in Aqua regis. The 
 
 4 
 
 Precipitate of Iron from Spirit of Salt is a 
 tenacious mafs : That of Silver from Aqua 
 fortis, fometirnes a white powder, fometirnes 
 tenacious : Copper from Aqua fortis is 
 
 fometirnes thrown down in form of a white 
 powder, and fometirnes in that of a green 
 Oil, according to the proportions and di~ 
 lutenefs of the liquor. Silver is not preci- 
 pitated at all by this acid from its folution in 
 Vinegar, nor Gold from Aqua regis. 
 
 An ounce of the vitreous Salt well mixed 
 with half an ounce of Soot, and committed 
 to diftillation, yielded a dram of fine Phoff- 
 phorus. The black refiduum being elixated 
 with boiling water, and the liquor palled 
 through a filter ; there remained upon the 
 filter eight fcruples of black matter, and on 
 evaporating and cryftallizing the liquor, 
 about feven drams were obtained of oblong 
 cryftals, which did not deliquiate in a moift 
 air, but became powdery in a warm one. 
 Thel’e cryftals, treated afrelh With inflam- 
 mable matter, yielded no Phofphorus. Be- 
 fore a blow-pipe, they melted into a tran- 
 fparent globular mafs, which on cooling be- 
 came turbid and opake. Diffolved in wa- 
 ter, they precipitated folutions of Silver, 
 Mercury, Copper, and of Chalk, though 
 they did not act upon the latter fo power- 
 fully, nor produce with it a gluey mafs, as 
 before they had been deprived of their phof- 
 phorine acid. 
 
 The author from whom we have taken 
 thefe curious experiments, fuppofes, that 
 the origin of the microcofmic Salt is in the 
 vegetable kingdom ; that it actually exifts, 
 all but its volatile alcaline part, in fundry 
 vegetable fubftances, and is thence com- 
 municated to the Urine of animals. He 
 finds that the feeds of Rocket, Creffes, Mil- 
 liard, and even Corn, on being urged with 
 a vehement fire, afford a true Phofphorus, 
 and of confequence muft contain the phof- 
 phorine acid : And that human Urine yields 
 more of the microcofmic Salt in fummer, 
 when vegetable foods are uled moft freely, 
 than in winter: This difference, however, 
 may depend, not upon the difference of food* 
 but upon the Urine being more dilute in 
 one feafon than in the other. 
 
 E 
 
578 Animal Excrements. 
 
 Urine, in fummer, and in young perfons than adults. By difeafes, it is fo much in- 
 
 V' - 1 — ,y -7 J fluenced, that in many cafes the appearance of the Urine is an ufeful afiiftance 
 to thephyfician in forming a judgment of the diftemper. Such as is voided in 
 the morning, or many hours after eating or drinking, is for obvious reafons the 
 mod faturated. 
 
 How far its quality is affeCled by particular aliments or liquors, is not clear : 
 There are fubftances which communicate to it a manifeft impregnation ; thus 
 Alparagus gives a fetid fmellfand Turpentine a violet one •, Rhubarb and Tur- 
 meric a deep yellow colour, and the pulp of Cafia fiftularis, a greenilh or 
 blackifh one : But that the drinking of Wine or Beer occalions any remarkable 
 difference, as the ancients fuppofed, there is little ground to prefume. 
 
 Its nature, Recent perfeCl Urine is not fenfibly alcaline or acid ; but in keeping, it foon 
 begins to putrefy and acquire an alcaline quality; and this change it fometimes 
 undergoes before its difcharge from the body. By putrefaClion, its marine 
 Salt is in part deftroyed or volatilized; and hence after diddling putrefied 
 Urine, we obtain from the Caput mortuum much lefs of that Salt than when 
 frefh Urine is ufed, and this in proportion as the putrefaction has been carried 
 to a greater or lefs length. 
 
 and ufes. Urine is made ufeofin fundry chemical arts ; as in dying, fcouring, making 
 Alum, Sal ammoniac. Nitre, UV. It has fometimes been employed in the 
 fhops as a precipitant for certain folutions : A Lac or white Precipitate is thrown 
 down by it from a dilution of Sulphur made by boiling Sulphur in water along 
 with Quick- lime ; and a rofe-coloured Precipitate, from a dilution of Quick- 
 filver in the nitrous acid. 
 
 Diftillation of The volatile fpirit and Salt of Urine are ufually prepared, by putrefying the 
 
 Urine-. Urine in large wooden tubs, and then diddling it with a gentle heat gradually 
 increafed. If the fire is railed a little too haftily, it fwells up and boils over : 
 This inconvenience may be prevented by rubbing the upper part of the veflei 
 all round with Tallow. 
 
 Some dephlegmate the putrefied Urine in open veffels, and then proceed to 
 the diftillation of the remaining thick matter ; but in this procefs, a good deal 
 of the fubtile fpirit is loft. The Urine may however be advantageoufly de- 
 phiegmated before putrefaClion, either by lire, or what is ftill more commodi- 
 ous where the feafon will permit, by freezing; for only the aqueous parts con- 
 geal, and by the feparation of thefe, the remainder becomes proportionably 
 more faturated. 
 
 By adding Quick-lime to the infpiffated Urine a cauftic volatile fpirit is ob- 
 tained, without putrefaClion, fimilar to that prepared by the fame intermedium 
 from Sal ammoniac : By this addition, the volatile fpirit is extricated without 
 the application of any external heat; the infpiffated Urine growing hot when 
 mixed with the Quick-lime, and this heat being fufficient to elevate a confider- 
 able part of the volatile penetrating fpirit. 
 
 The rectification of the Spirit, Salt, and Oil of Urine, is performed in the 
 fame manner as of thofe of other animal lubftances. I have had an Oil of 
 Urine, which tafted as fweet as Sugar. From the Caput mortuum is obtained, 
 by elixation with water, the Sea-falt; and by calcining and then elixating it, a 
 fixed alcaline one. I have prepared from this fubjeCt two fixed alcalies, differ- 
 
 in g 
 
Animal Excrements. 579 
 
 mg from one another ; one grofier, and the other more fubtile. The marine U r i n e. 
 Salt alfo is more fubtile than common Sea-falt : QndiHilling the entire Caput i- ■ — Y 
 mortuum with the addition of fuch fubftances as extricate the acid of Sea-lalt, 
 there arifes an acid fpirit, fimilar in its general properties to the marine, but in 
 fome refpebls different from it. 
 
 THE Phofphorus of Urine, called emphatically Phofphorus, by fome Phof- Phofphorus: 
 phorus ure'ns, phofphorus glacyilis, nofliluca glacialis, noEliluca aerea y was caiuaily Its Pillory, 
 dilcovered, about the year 1669, by one Krafft, a German cbemifl. Soon 
 after, Kunckel prepared it-, and one Brand, having procured fome pieces, 
 though unacquainted with the method of making it, went into England, 
 
 France, &c. and arrogated to himfelf the honour of the difcovery. Ac length 
 Mr. Boyle and Mr. Homberg found out the fecret; and Godfrey Hanckwitz, 
 then operator to Boyle, improved, refined., and perfected the Phofphorus. 
 
 The Phofphorus is obtained by diftilling in a Hrong fire either infpiffatedp re P a r at iofi. 
 Urine, or the Caput mortuum remaining after its diffilJation in the common 
 manner. Some additional matters are generally mixed with the infpiffated 
 Urine-, Homberg ufes red Bole ; Boyle, white Sand; and Boerhaave, pow- 
 dered Charcoal. An account of the manner of conducing the procefs may be 
 feen in the Memoirs of the French Academy and other books. If we have a 
 good furnace, and a retort that will Hand a fierce fire, there is no difficulty in 
 obtaining the Phofphorus in fmall grains, like Millet-leed or Lentils : But in 
 preparing it into fine large white Hicks, like pieces of tobacco-pipes, no one has 
 hitherto lucceeded like Mr. Godfrey. It congeals, at the bottom of the reci- 
 pient, like the ice of dirty water in kennels, and requires a further purification 
 from its brown and blackifli matter («). 
 
 A good 
 
 («) Procefs for Plxifphorus .] Mr. Hellot, in 
 the Memoirs of the French Academy for 
 the year 17375 has given a very particular 
 account of the molt luccefsful manner of 
 conducting this operation. If his directi- 
 ons are carefully followed, it will be im- 
 poffible, he fays, to mifcarry. 
 
 A large quantity of Urine, after {landing 
 to putrefy for at lealt five or fix days, is to 
 be evaporated in an iron kettle, till the mat- 
 ter grows thick and black: It is then to be 
 kept conftantly flirring, to prevent its form- 
 ing a hard incruftation upon the veflel, till 
 it is reduced into a Ihining, black, clotty, 
 powdery fubftance, like Soot. 
 
 This dry refiduum is to be calcined in an 
 iron pot, by five or fix pounds at a time, 
 with a fire fufficient to make the veffel red- 
 hot. The calcination is to be continued, 
 and the matter kept flirring, till it has loit 
 almoft all its volatile Salt and fetid Oil, that 
 is, till it ceafes to frnoke, and acquires a 
 fmell like that of Peach blofloms. 
 
 4 
 
 The calcined matter is to be freed from 
 the fuperfluous marine Salt of the Urine 
 (which feparating and melting in the diftil- 
 lation, would corrode the retort) by elixation 
 with water. To every pound, put a pint 
 and a quarter ot water ; ftir them together, 
 and let them ftand for twenty-four hours ; 
 then decant oft' the faline liquor, and dry 
 the remaining powder. 
 
 Sixty gallons of Urine leave on evapora- 
 tion about ten pounds of dry matter. This 
 lofes in the calcination about one third its 
 weight, and in the elixation about one half 
 of the remainder ; and thus is reduced to 
 three pounds or three and a half ; a quantity 
 fufficient for one diftillation, and which will 
 yield an ounce or more of Phofphorus. 
 
 Three pounds of the elixa'ced powder are 
 to be mixed with a pound and a half ot 
 coarle Sand, and four or five ounces of 
 powdered Charcoal. The Sand Ihould not 
 be that of rivers, for this crackles and flies 
 about when ftrongly heated ; nor the Char- 
 E ^ coal 
 
5 8 ° 
 
 U R I N 
 
 L i 
 
 Animal Ex 
 
 E. coal that of Oak, which is accompanied 
 
 „j w ith the fame inconvenience. The mix- 
 ture is to be moiftened with about half a 
 pound of water, and made into a mafs, to 
 be put into a Helfian retort of fuch a fize 
 that one third of it may remain empty. The 
 common earthen-retorts or long-necks are 
 incapable of (landing the intenfe firerequi- 
 fxte for this operation. 
 
 Before we proceed to the diftillation, it 
 will be proper, for the greater fatisfailion 
 and fecurity, to make an aflay of about an 
 ounce of the mixture in a fmall crucible 
 made gradually red-hot. If it has been 
 duly prepared, it will fmoke and crack, 
 without (welling or rifing ut> : White or 
 
 bluifh undulating flames will arife impetu- 
 oufly from the cracks : On placing upon 
 the crucible, when thefe difappear, a large 
 piece of lighted Charcoal, the true Phof- 
 phorus will difcover itfelf in a fteady, lumi- 
 nous, fomewhat violet-coloured vapour, co- 
 vering the whole furface, and fmelling 
 (Irongly of Garlic. When this vapour is 
 diflipated, pour the hot .matter upon an 
 iron plate : If no particle of Salt can be feen 
 in it, we have nothing to fear ; but if 
 any drop of Salt has melted out and ap- 
 pears diftinil, the elixation with water muft 
 be repeated or the retort will be in danger. 
 
 The retort, charged with the mixture, is 
 to be placed in a reverberatory furnace, fo 
 conftruiled as to be capable of giving as 
 fierce a heat as that of the glafs-houfe fur- 
 naces. Adapt to the retort a large glafs 
 receiver filled to one third with water; and 
 fecure the junilure with a mixture of to- 
 bacco-pipe Clay and drying Oil, over which 
 is to be fpread fome common lute moiftened 
 With a (olution of Glue. 
 
 It is mdifpenfibly necefiary that the junc- 
 ture be perfeilly tight ; but it is equally ne- 
 ceflary that an exit be allowed to the elaftic 
 vapours, which otherwife would infallibly 
 burft the veffels. If we endeavour to give 
 them vent by an upright tube inferted in the 
 luting, as is cuftomary in other operations, 
 the heat of this part of the veflel would fire 
 the fubtile phofphorine vapours that arife 
 firft, and thefe would kindle the true Phof- 
 phorus which fucceeds. An aperture is 
 therefore to be made in the further part of 
 the receiver itfelf, about four or five inches 
 above the furface of the water: This is the 
 grand fecret in the whole procefs. It will 
 
 CREMENTS. 
 
 be eafy to contrive means of grinding a 
 fmall hole through the glafs with Emery ; 
 which hole is to be fitted with a little birchen 
 plug furnifhed with a knob to keep it from 
 flipping in. 
 
 The apparatus having flood for three or 
 four days, till the luting is dry ; and the 
 cracks, if any have happened, being repaired; 
 proceed to the diftillation. This Tafts com- 
 monly four and twenty hours. Mr. Hellot 
 begins at two in the morning, by putting 
 an unlighted coal into the a(h-hole, and a 
 lighted one at the door, which kindles the 
 other. By gradually fupplying a little more 
 fuel in the afh-hole, the furnace and luting 
 become thoroughly dry, and the phlegm of 
 the mixture diftils. At fix, fome coals are 
 laid on the grate ; which being (oon 
 kindled by the fire underneath, the receiver 
 grows warm, and is filled with white fetid 
 vapours. At ten, thefe vapours difappear, 
 the receiver grows cool, and the fire is to be 
 increafed and fteadily kept up. About 
 noon, a faline fubftance, different from the 
 common volatile Salt of Urine, begins to 
 concrete in elegant ramifications all over 
 the internal furface of the recipient, and is 
 by degrees diflolved and wafhed down by 
 the fleam of the water in that veflel. About 
 three after noon, the receiver is filled with 
 frefh vapours, which fmell like Sal ammo- 
 niac thrown on burning coals, and which 
 condenfe into faline ftriae not difloluble by 
 the fteam of the water. Thefe are the 
 forerunners of the Phofphorus, and towards 
 the end of their diftillation they lofe the am- 
 moniacal and acquire a phofphorine or Gar- 
 lic fmell. As they come over with great 
 rapidity, the aperture in the receiver muft 
 now be frequently unftopt ; and if the va- 
 pour hides forth impetuoufty, the heat muft 
 be diminifhed by clofing up the air-draughlts 
 of the furnace. Thefe white vapours con- 
 tinue about two hours ; after which the fire 
 is to be railed, and kept up moderately 
 ftrong. About fix, the more volatile phof- 
 phorine fumes beginning to arife, the 
 birchen peg rubbed upon any warm part of 
 the furnace leaves a luminous trail; and 
 foon after, there darts through the aperture 
 in the receiver a ftream of bluifh light, which 
 does not burn, but renders the hands lumin- 
 ous. On unftopping the aperture from time 
 to time, the luminous ftream is obferved 
 gradually to lengthen to feven or eight 
 
 inches $ 
 
Animal Excrements. 
 
 5 8i 
 
 inches ; and afterwards to grow fhorter, to 
 crackle, fparkle and burn. In about two 
 hours from the firft appearance of this vola- 
 tile Phofphorus, the (mall jet of light con- 
 trails to the length of one or two twelfths 
 of an inch: There is now no danger of 
 the veffel’s burfting ; pu(h the fire boldly 
 to the utmoft extremity, and for fix or (even 
 hours keep up fuch a white heat, that the 
 retort cannot be diftinguifhe '. In this ex- 
 treme degree of heat, the true Phofphorus 
 comes over, in the form of Oil or melted 
 Wax, partly fwimming upon the water in 
 the receiver, and partly finking to the bot- 
 tom. At length the upper part of the reci- 
 pient, where the volatile Phofphorus had 
 condenfed into a black film, begins to grow 
 red ; a mark that the Phofphorus is there 
 burnt, and that the operation is finifhed. The 
 furnace is now to be fhut up clofe, and the 
 aperture in the receiver llopt with Fat, 
 Lute, or melted Wax. All the empty 
 part of the receiver appears luminous till the 
 vefiels are grown cold. 
 
 When the whole is become thoroughly 
 cold (not before, left the Phofphorus fhould 
 take fire) feparate the receiver, and expedi- 
 tioufly wipe out the black matter about its 
 mouth, which mingling with the Phofpho- 
 rus would injure its tranfparency. A quan- 
 tity of cold water is to be poured into the 
 receiver, to wafti out and promote the fet- 
 tling of the Phofphorus ; and the whole 
 poured into a clean earthen pan. The cold 
 water being decanted off, fome boiling wa- 
 ter is to be added to melt the Phofphorus, 
 which now forms a mafs of a (late colour, to 
 be broke in pieces, when cold, in frefh cold 
 water. 
 
 The Phofphorus is purified and formed 
 into (licks, by melting it in boiling water in 
 glafs tubes. The neck of a matrafs, having 
 its mouth or lower aperture ftopt with a 
 cork and greateft part of its body cut off", 
 forms a convenient veftel for this purpofe. 
 T he tube being filled v/ith the boiling li- 
 quor, throw in the pieces of Phofphorus, 
 which foon liquefy and fink to the bottom: 
 Stir the liquid matter with an iron wire, to 
 promote the feparation of the impurities, 
 and keep the water boiling till, on taking 
 out the tube, the Phofporus appears clear 
 and tranfparent. The tube being then 
 cooled a little in the air is to be plunged in 
 cold water, to make the Phofphorus con- 
 
 geal. The flick is to be pufhed out at the Ur i n e* 
 wider end of the tube, and the impure part t — - > 
 
 at top cut off. 
 
 Mr. Hellot lays, that from three pounds 
 and a half of the calcined and elixated mat- 
 ter he obtained fix flicks of Phofphorus, 
 each four inches long, weighing in all nine 
 drams and fome grains, at leaft equal in 
 quality to that made by Mr. Godfrey ; and 
 that he was informed that Mr. Godfrey 
 ufed a receiver with a vent-hole, and inftead 
 of infpiffated Urine the fettlings procured 
 from the dyers. In cafe of accidents from 
 the Phofphorus taking fire, he finds nothing 
 to extinguifh it but Urine. 
 
 There is one ftep in this procefs, which 
 requires further examination, and which, fo 
 far as I can judge from the experiments 
 that have as yet been made, is rather preju- 
 dicial than ufeful. We have formerly feen 
 that Urine contains a certain fixed acid Salt, 
 of a peculiar kind ; and that the Phofpho- 
 rus confifts of this acid combined with in- 
 flammable matter. Now as this Salt dif- 
 folves eafily in water, it fhould feem that 
 the elixation of the calcined Urine could not 
 fail to feparate a great part of this effential 
 ingredient, as well as the marine Salt of the 
 Urine; and in effect, the faline liquor dif- 
 covers, upon trial, plain marks of the mi- 
 crocofmic or phofphorine Salt. 
 
 More than double the above quantity of 
 Phofphorus has been obtained, in lets time 
 and with lefs fire, by adding certain (aline 
 fubftances to the infpiffated Urine, inftead of 
 feparating any of its native Salts. This dis- 
 covery was firft made by Henckel, in treat- 
 ing calx of Lead with Sai ammoniac, Salt of 
 Tartar, and dale Urine, in a view to the re- 
 folution or mercurification of the metal. 
 
 Mr. Marggraf has re-examined and profe- 
 cuted the experiment, and found J'aturnus cor~ 
 neus , or a combination of Lead with the 
 marine acid, to be the bed addition. 
 
 Saturn us corneus is mod commodioufly 
 prepared bv mixing Sal ammoniac with 
 twice its weight of Minium, and expofing 
 them to a moderate heat : The volatile Al- 
 cali of the Sal ammoniac is extricated, and 
 its marine acid remains combined with the 
 faturnine calx into a brittle reddifh mafs. 
 
 Nine or ten pounds ot infpiffated Urine, 
 about the confidence of thin Honey, were 
 fet to evaporate further in an iron pot ; three 
 
 pounds 
 
5 82 Animal Excrements. 
 
 Urine. A good deal of caution is requifite in all operations with this inflammable 
 C. — . — 1 concrete: Mr. Godfrey himfelf, notwithftanding his large experience, was 
 once in danger of his life from it, his hand being burnt fo terribly, that 
 for a time he was out of his fenfes, and for three days lay in exquifite pain, as if 
 his hand had been conftandy in a fire. 
 
 This Phofphorus is fet on fire by rubbing as well as by the application of 
 tics pr ° l,C1 ' actual heat-, and burns far more vehemently, and with a more piercing heat, 
 than any other known fubftance. Expofed to a temperate air, it appears lu- 
 minous like a burning coal, and emits a continual offenfive fmoke, till the 
 whole quantity is diffipated. Characters drawn with it on paper or other fub- 
 ftances, appear alfo, in the dark, as if they were on fire. It is very flowly 
 confumed ; a fingle grain diftufing a feemingly burning light for fifty hours 
 together. 
 
 Though this concrete takes fire fo readily when rubbed by itfelf, it does not 
 fire at all by grinding it with other inflammable bodies, as Camphor, Gun- 
 powder, or efiential Oils. In grinding it with Nitre, lome luminous ftafhes 
 are obferved, but the mixture never burns, unlefs the quantity of Phofphorus 
 be large in proportion to the Nitre. Rubbed pretty hard on a piece of Paper 
 or Linen, it fets them on fire if they are rough, but not if they are fmooth : 
 It fires written Paper more readily than fuch as is white, probably from the 
 
 former 
 
 pounds of the above Saturnus corneus in 
 powder, and half a pound of powdered 
 Charcoal, gradually mixed in ; and the 
 whole kept llirring, till reduced into a dry 
 blackifh powder. This, urged with a red 
 heat, gave over a fmall portion of urinous 
 fpirit and an ammoniacal Sublimate ; after 
 which it was pulverized afrefh, in order to 
 the more perfedi mixture of the ingredients. 
 A little of it, being examined on burning 
 coals, gave inftantly an arfenical or phof- 
 phorine fmell, and an undulating blue flame. 
 
 With the powder thus prepared, were 
 charged, to three fourths of their capacity, 
 fix earthen pint retorts; the fire adling to 
 better advantage upon a number of fmall 
 vefiels, than on a large one equivalent to 
 them. To each retort was luted a glafs re- 
 ceiver, fomewhat more than half filled with 
 a pint of water, which was made almoft to 
 touch the end of the neck of the retort. 
 The fire being gradually raifed, and kept 
 up ftrong for an hour and a half, the Phof- 
 phorus came over in drops which being col- 
 leiSied and purified, amounted in all to two 
 ounces and a half of as fine Phofphorus as 
 can be made. The whole continuance of 
 the diftillation was but four hours and a 
 half. 
 
 Luna cornea had much the fame effect as 
 
 Saturnus corneus. With Calamine alfo the 
 quantity of Phofphorus was larger than the 
 Urine by itfelf would have afforded. 
 
 The acid of Phofphorus agrees in fome 
 of its properties with the marine acid, and 
 is fuppofed by the chemifts to be at bottom 
 no other than the marine, altered a little by 
 the admixture of fome other matter. 
 
 As the vitriolic acid forms with inflam- 
 mable matter common Sulphur, and the ni- 
 trous a compound which deflagrates in the 
 clofeft veffels the very inftant it is formed ; 
 fo the marine is held to produce, with the 
 fame inflammable principle, this Angular 
 fpecies of Sulphur, more inflammable than 
 the one, and lei's fo than the other. 
 
 This theory, firft advanced by Stahl, is 
 countenanced by the p’nofphorine flame 
 which arifes from common Salt thrown 
 on burning coals. Hence trials have been 
 made for procuring Phofphorus without 
 Urine, from common Salt or its acid and 
 vegetable or animal inflammable matters ; 
 but hitherto without fuccefs. And indeed 
 the acid feparated from Phofphorus, as we 
 fhall fee’hereafter, is in many of its proper- 
 ties extremely different from the marine, 
 and from all other known acids or combi- 
 nations of acids. 
 
Animal Excrements. 583 
 
 former having more afperities. On grinding it with iron filings it prefently Urine. 
 takes fire. t — — v — — > 
 
 Oils, ground with Phofphorus, appear like it feif luminous in a temperately 
 warm place, and thus become a liquid Phofphorus, which may be rubbed on 
 the hands, &c. without danger. Liquid Phofphorus is commonly prepared, 
 by grinding a little of the folid Phofphorus with Oil of Cloves, or rubbing it 
 frirfb with Camphor, and this mixture with the Oil. A luminous Pomatum is 
 obtained in the fame manner, by tiling common Pomatum inftead of the di- 
 ftilled Oil. A luminous amalgam, as it is called, is prepared by digefting a 
 fcruple of the folid Phofphorus, reduced into fmall bits, with half an ounce of 
 Oil of Lavender; and when the Phofphorus begins to diffolve, and the liquor 
 to boil, adding a dram of pure Quickfilver ; then brifkly fhaking the glafs for 
 five or fix minutes, till they unite. 
 
 Rectified Spirit of Wine, digefted on Phofphorus, extracts a part of it, foas 
 to emit luminous fiafhes on being dropt into water: It is computed that one 
 
 part of Phofphorus will communicate this property to fix hundred thoufand 
 parts of fpirit : The liquor has never been obferved to appear luminous by it- 
 felf, nor in any other circumftance than that above-mentioned. By digeftion 
 for fome months, the undilfolved Phofphorus is reduced into a transparent Oil, 
 which neither emits light, nor congeals in the cold: By wafhing with water, 
 
 it is in fome meafure revived ; acquiring a thicker confidence, and becoming 
 again luminous, though in a lefs degree than at firft. The operator ought to 
 be on his guard during the digeftion, as the glafs is very apt to burft. No 
 menftruum is as yet known, that readily and perfectly diflblves this concrete. 
 
 Dr. Cyprianus hit once on luch a menftruum, but never could fucceed 
 again [x). 
 
 With 
 
 ( x ) Solubility , &c. of Phofphorus.'] This 
 concrete diflblves partially in exprelfed Oils, 
 and totally or almoft fo in efiential Oils and 
 ./Ether : When efiential Oils are fatu- 
 
 rated with it by heat, a part of the Phof- 
 phorus feparates on Handing in the cold, in 
 a cryfialline form. 
 
 Concentrated Spirit of Salt has no affion 
 on it ; in diftillation, the fpirit arifes firft, 
 and the Phofphorus after it, unchanged. 
 
 Spirit of Nitre diflblves it : The abtion of 
 this acid is accompanied with great heat and 
 copious red fumes, infomuch that great part 
 of the fpirit diftils without the application of 
 any external heat, and the Phofphorus at 
 laft takes fire, explodes, and burfts the 
 veflel. 
 
 Oil of Vitriol likewife diflblves Phofpho- 
 rus, but not without a heat fufficient to 
 make the acid diftil : The diftilled liquor is 
 thick, white, and turbid ; therefiduum is a 
 whitifh tenacious mafs, which deliquiates, 
 but not totally, in the air. Phofphorus it- 
 
 felf is refolved into an acid liquor on being 
 expofed for two or three weeks to the air, 
 its inflammable principle feeming by degrees 
 to be diflipated. 
 
 Phosphorus has been reported to pro- 
 duce extraordinary effects in the refolution 
 of metallic bodies ; but from the experi- 
 ments that have been made in this view, it 
 does not appear to have any remarkable 
 affion on them, at leaft on the precious 
 ones Gold and Silver, for the refolution or 
 fubtilization of which it has been chiefly re- 
 commended. The following experiments, 
 were made bv Mr. Marggraf. 
 
 1. A fcruple of filings of Gold was di- 
 gefted with a dram of Phofphorus for a 
 month, and then committed to diftillation. 
 Part of the Phofphorus arofe, and part re- 
 mained above the Gold, in appearance re- 
 fembling Glafs : This grew moift on the 
 
 admiflion of air, and diftolved in water, 
 leaving the Geld unaltered. 
 
 2. Half 
 
5 8 + A nimal Excrements. 
 
 Urine. With regard to the compofition of this Phofphorus, one of its principles is 
 
 — ' apparently the concentrated inflammable fubftance of the animal Oil of the 
 
 Urine : The other is the concentrated acid of the marine Salt of the Urine. 
 The water, in which the Phofphorus has been long kept, (for it is commonly 
 kept in water to preferve it from diflipation,) is manifeftly acid to the tafte, 
 and on mixture with different lubftances is found to poflefs the general proper- 
 ties of acid liquors : On burning the Phofphorus in a Silver veflel, a quantity 
 of acid remains behind (jy). 
 
 IT 
 
 2. Half a dram of fine Silver precipitated 
 by Copper being digefted with a dram of 
 Phofphorus for three hours, and the fire 
 then increaled to diftillation, greateft part 
 of the Phofphorus arofe pure, and the Silver 
 remained unchanged. 
 
 3. Copper filings being treated in the 
 fame manner, and with the fame quantity of 
 Phofphorus ; the Phofphorus fublimed as 
 before, but the remaining Copper was found 
 to have loft its metallic brightnefs, and to 
 take fire on the contadf of flame. 
 
 4. Iron filings fuffered no change. 
 
 5. Tin filings run into granules, which 
 appeared to be perfect Tin. 
 
 6. Filings of Lead did the fame. 
 
 7. The red calx of Mercury, called Pre- 
 cipitate per fe, treated in the lame manner, 
 was totally revived into running Quickfilver. 
 
 8. Regulus of Antimony fuffered no 
 change itfelf, but occafioned a change in 
 the confiftence of the Phofphorus, which 
 after being diftilled from this femimetal, re- 
 fufed to congeal, and continued, under wa- 
 ter, fluid like Oil Olive. 
 
 9. With Bifmuth, there was no altera- 
 tion. 
 
 10. A dram of Phofphorus being diftilled 
 and cohobated with an equal quantity of 
 Zinc ; greateft part of the Zinc fublimed in 
 form of very light, pointed flowers, of a 
 reddifh-yellow colour : Thefe flowers, in- 
 je£ted into a red-hot crucible, took fire, and 
 run into a glafs, refembling glafs of Borax. 
 
 11. White Arfenic, fublimed with Phof- 
 phorus, arofe along with it in form of a 
 mixed red Sublimate. 
 
 12. Sulphur unites readily with Phofpho- 
 rus, into a mafs which fmells like Hepar 
 fulphuris. This does not eafily take fire 
 upon being rubbed ; but expofed to a mo- 
 
 derate dry heat, it flames violently and e- 
 mits a ftrong fulphureous fume, 
 
 (y) Acid of Phofphorus.] The properties of 
 this extraodinary acid, fo far as they have 
 hitherto been difcovered, are thefe. 
 
 1. It is the moft fixed of all acids, and is 
 not volatilized by flame, fince it remains 
 after the burning of the Phofphorus, and 
 may be collected in notable quanticy even 
 in an open veflel. If a veflel is placed over 
 the burning Phofphorus, a quantity of light 
 flowers concretes in it, which diflolve in 
 the air into an acid liquor fimilar to that 
 which remains in the lower veflel. 
 
 2. On diftilling ofF the phlegm of the 
 acid liquor in glafs veflels, a folid faline fub- 
 ftance remains ; which on raifing the fire 
 melts into the appearance of Glafs. The 
 vitreous matter, urged with a blow-pipe on 
 a piece of Charcoal, runs into a round bead, 
 which rolls about like Silver in the cupel. 
 Expofed to the air, it foon grows moift, 
 and by degrees runs into an acid liquor 
 again. 
 
 3. This acid, faturated with pure fixed 
 alcaline Salt, fhoots into cryftals ; which, 
 before a blow-pipe, do not crepitate like 
 marine Salt, but bubble and boil like Bo- 
 rax, and then fink into a pellucid vitreous 
 bead. 
 
 4. Saturated with volatile Alcali, it 
 fhoots into oblong fpicular cryftals, which 
 melt in nearly the fame degree of heat that 
 Lead does, and in a ftronger fire part with 
 their volatile Alcali, a femivitrefied fub- 
 ftance remaining. 
 
 5. It totally diflolves Zinc, Iron, Calx 
 of Copper, and white Arfenic. Lead, Tin, 
 and Copper filings, it diflolves only par- 
 tially. Silver and Gold it has no action 
 upon at all,. 
 
 4 
 
 6. Mixed 
 
Animal Excrements. 
 
 5 6 7 8 S 
 
 I T was in fearching for alchemical fecrets, that the Phofphorus of Urine Alvine 
 was difcovered. The alchemifts have fearched alfo in the Alvine feces, but Feces. 
 nothing of much importance has refulted from the fulfome labour. Horn- i — — * 
 berg obferved that the fecal matter calcined with Alum proves a fpecies of 
 Phofphorus, which takes fire on being expofed to the air ; but the fame pro- 
 du£t is found to be equally parable from Alum and any other animal or vege- 
 table inflammable matter. In fome proceffes, the human fecal matter has 
 yielded a fmell like that of Mufk or Civet : A tindmre made from it in fweet- 
 fcented waters or rather vinous fpirits, evaporated by a gentle heat to a thick 
 confidence, is called by fome occidental Civet. 
 
 The dungs of different animals have been employed in medicine •, not only 
 for external purpofes; but likewife internally, in the form of infufion, fpiri- 
 tuous tindlure, and fometimes of powder. As one of thefe differs remarkably 
 from the other fubftances ofthisclafs, I fhall give an account of the experi- 
 ments I have made upon it. 
 
 Album-gr cecum , or the white dung of a dog that feeds upon bones, feems to Album- 
 confifl chiefly of the earthy part of the bones, and to have very little of a fter-cR^cuM. 
 coraceous nature. u— — v"— ^ 
 
 Half an ounce, digefted with rectified Spirit of Wine, gave three grains of 
 a blackifh extract, which had neither fmell nor tafte : The fame quantity, 
 boiled in frefb parcels of pure diftilled water, gave twenty grains of extract, 
 in colour blackifh, in tafte quite faline like the watery extract of bones. The 
 remaining powders had the fame appearance as at firfl ; In diflillation, the 
 fpirit arofe unaltered ; and the diftilled water had only a very flight kind cf 
 unpleafant fmell. 
 
 Spirit of Vitriol diffolved a little of th t Album- gr tecum, and acquired from it 
 a yellowifh tinge; but there was no appearance of the cryftalline concretions, 
 
 which 
 
 6. Mixed with a folution of Gold, it oc- 
 cafions no turbidnefs or precipitation. Af- 
 ter the liquor has flood for fome time, a 
 little of the Gold is depofited in its bright 
 metallic form. Mr. Marggraf relates, that 
 upon diftilling the mixture by a ftrong fire, 
 fome obfeure yellow drops appeared ; that 
 the reliduum was of a purple colour, and 
 lightly covered with reduced Gold, and 
 that before a blow-pipe it run with eaie into 
 an opake glafs-like fubflance. 
 
 7. Silver, diffolved in volatile Alcali, is 
 precipitated by this acid of a yellow colour, 
 not white as by the marine acid. The 
 fame metal, diffolved in fixt Alcali that has 
 been impregnated with animal inflammable 
 matter, is precipitated by the phofphorine 
 
 acid of a red colour, whilfl the marine acid 
 makes no precipitation at all. 
 
 8. Solution of Mercury in Aqua fortis is 
 copioufly precipitated by the phofphorine 
 acid, but on {landing greateil part of the 
 Precipitate is taken up again ; what re- 
 mains undiffolved is a ponderous black pow- 
 der. In diflillation, a notable quantity of 
 white Ihining matter is left, which before a 
 blow-pipe melts into a pellucid glafs : Oa 
 continuing the flame greateft part of the 
 vitreous matter finks into the coal and 
 fmokes away. 
 
 9. Solution of Lead in Aqua fortis depo- 
 fites on the addition of the phofphorine' 
 acid a white powder, which on {landing is 
 not rediffolved. The matter which re- 
 mains upon diftilling this mixture, melts by 
 a blow-pipe into a beautiful pellucid glafs 
 drop, without fumes, and without any revi- 
 val of the Lead. 
 
 4 F 
 
5 86 
 Album- 
 
 CR/5ECUM. 
 
 Animal Excrements. 
 
 which ufually feparate from folutions of other animal earthy bodies made 
 in this acid. Spirit of Nitre diflolved nearly the whole, and Spirit of Salt 
 about one half ; both thefe became likewife yellowifh. Spirit of Sal ammo- 
 niac, common alcaline Ley, and cauftic Ley, extracted alfo a yellowifh tinc- 
 ture, without difcovering any further a&ion. 
 
 Two ounces, diddled in a retort, gave over two drams and a half of clear 
 water which had no fmell or tafte, then one dram and a half of a yellow em- 
 pyreumatic liquor, and afterwards half a dram of an empyreumadc Oil of a 
 volatile fmell : The Caput mortuum weighed one ounce three drams. 
 
 INDEX. 
 
1 'he Letter n refers to the Notes , 
 
 A. 
 
 /(C 1 DS in general, p. 159 
 
 Their characters, ib. 
 
 Diffolve the afhes of vegetables, 478, n. 
 and of the foft parts of animals, 494, n. 
 Unite with alcalies into neutral Salts, 
 V. Neutral. 
 
 To change the colour of blue flowers to 
 red, not peculiar to acids, 187, n. 
 
 nor common to all acids, 164, n. 
 
 Subftances diffolved in alcalies, not uni- 
 verfally precipitated by acids, 194,0. 
 
 488, n. 
 
 precipitated by fubftances void of aci- 
 dity, 5, n. 
 
 Method of determining their ftrength, 162 
 Strength, power, and activity, diftind 
 properties, 162, n. 
 
 Order of their affinity to different bo- 
 dies, 172 
 
 Of different kinds, 159 
 
 Converfion of one kind into another, 195 
 Acid, Animal , 482 
 
 Latent, in blood, &c. 491 
 
 how feparated, ib. 
 
 of the marine kind, 492, n. 
 
 Manifeft in Ants, &c. 497. 
 
 how collected and concentrated, 497, 498 
 its habitude to different bodies, 499, n. 
 its analogy with vegetable acids, ib. 500, n. 
 Acid , Marine , 207 
 
 Its characters, ib. 
 
 how diftinguifhed in mixture, 253, n. 
 Exhales in white fumes, 208 
 
 As a menftruum for earths, 225 
 
 As a menftruum for metals, 208 
 
 made to diffolve Gold, ib. 33, n. 
 
 combinable with all metallic bodies, 208 
 diffolves metallic calces, ib. 
 
 Its affinities with different metals, 209 
 anomalous affinities, ib. 
 
 Strongly detained by calcareous earths, 1 6 
 adheres ftrongly to metals, and volatilizes 
 
 them. 
 
 208 
 4 
 
 Acid, Marine , feparable from fixt alcalies 
 by fire and water, p. 211, n. 
 
 Expelled from alcalies and earths by the 
 nitrous and vitriolic acids, 207 
 
 expels thofe acids from fome metals, 209 
 expels vegetable acids from all the bodies 
 it aCts on, 163, n. 207 
 
 Renders bodies combined with it fu- 
 fible, 20S 
 
 Unites with vinous fpirits more imper- 
 feCIly than other acids, 456, n. 
 
 Renders calcareous earths foluble in 
 vinous fpirits, 16, n. 
 
 as alfo moll metals, 34, n, 
 
 not volatile alcalies, as the nitrous acid 
 does ; nor fixed alcalies as the acetous. 
 Increafes the coldnefs of ice, iefs than 
 the nitrous, 196 
 
 Sea-fa! t in fubftance produces greater 
 cold with ice, and much lefs with 
 water, than Nitre in fubftance. 
 
 Acid, Nitrous, 195 
 
 Its characters, 253, n. 
 
 how diftinguifhed in mixture, ib. 
 
 Exhales in red fumes, 195 
 
 As a menftruum for earths, 8, 17 
 
 As a menftruum for metals, 19A 
 
 made to diffolve or corrode all metallic 
 bodies, ib. 
 
 ads moft violently on thofe which have 
 moft phlogifton, 197 
 
 diffolves not metallic calces, 196 
 
 Produces heat and fumes in diffolving 
 metals, ib. 
 
 not in diffolving earths, 8 
 
 Its affinities with different bodies, 197 
 Volatilizes calcareous earths, 17, n„ 
 
 difunited by fire from metals, 47, 134 
 From alcalies and earths expelled by the 
 vitriolic, 162 
 
 expels the marine, 207 
 
 From fome metals expels the marine, 197 
 from others, expelled by it, ib. 
 
 Its combination with vinous fpirits, 455 
 F 2 Add, 
 
index. 
 
 Acid, Nitrous , makes volatile Alcali fo- 
 luble in vinous fpirits, p. 197 
 
 Burfts into flame on being haftily mixed 
 with Oils, _ 195 
 
 Deflagrates in the fire with all inflam- 
 mable matters, *9^ 
 
 Inereafes the coldnefs of ice more than 
 any other acid, 196, n. 
 
 Volatilized, and tinged blue, 142 
 
 Artificially produced, I 95»455 
 
 changed into vitriolic, 195 
 
 deftroyed, 196, 203, 455 
 
 Add, Phcfphorine , 
 
 How obtained from Phofphorus, 584 
 Contained in fome vegetables, 577, n. 
 Suppofed of the fame nature with the ma- 
 rine, 582, n. 
 
 Differences from the marine, ib. 
 
 A flumes a vitreous form by dephlegma- 
 tion, 584* n> 
 
 Its effedts on metals and metallic folu- 
 tions, 585? n - 
 
 Its combination with alcalies, 584, n. 
 
 Acids , Vegetable. 
 
 Do not coagulate blood, 551 
 
 nor whites of Eggs, 555 
 
 Lefs powerful than the mineral, 163, n. 
 Their different kinds : 
 
 Cryftalline acid Salt from juices of acid 
 fruits, 4 2 3 > n * 
 
 from juices of herbs, 278,423 
 
 general properties of thefe Salts, ib . 
 Cryftalline acid Salt from fweet juices by 
 fermentation, 456 
 
 V. Tartar. 
 
 Acetous acid by fermentation, 440 
 
 V. Vinegar. 
 
 Acid fpirit from moft vegetables by diftil- 
 lation, 462 
 
 collected to advantage in making Pitch, 
 
 288 
 
 Add, Vitriolic , 160 
 
 Its charafters, ib- 
 
 diftinguifhed in mixture, 253,11. 
 
 In what bodies contained, 160 
 
 Does not exhale in the air, ib. 
 
 Imbibes moifture from the air, ib. 
 
 Its phlegm fuppofed different from com- 
 mon water, 162 
 
 By dephlegmation in clofe veflels, be- 
 comes folid, 161 
 
 Experiments with it on earths, 184 
 does not, like other acids, diflolve cal- 
 
 careous earths, 
 
 Its faturation with fixt alcalies in different 
 circumftances, 19 1 
 
 As a menftruum for metals, 172 
 
 Its general relation to different bodies, 162 
 Does not, like other acids, promote fu- 
 fion or volatility, ib. 
 
 Cryftallizes with all the bodies it dff- 
 iolves, 162 
 
 thecryftalsnot deliquiable in a moiftair,/A 
 
 calcine in a warm air, 
 
 J 79> 193 
 
 184 
 
 ©r the alhes of bones and horns, 494, n. 
 united with calcareous earths into Sele; 
 nitae, 8, n. 19, 
 
 or difficultly diflolve in water, 190 
 
 Difunited by fire from metals, 178 
 
 and from the earth of Alum, 188 
 
 not from alcalies, 160 
 
 nor from calcareous earths. 
 
 Diffipated from fixt Alcali by contact of 
 burning fuel, 475 
 
 and from calcareous earth, 19, n. 
 
 Expels other acids from alcalies and earths, 
 
 162 
 
 expelled by the marine from fome metals, 
 
 ^2,98 
 
 Its affinity to different metals, 1 78, 172, n. 
 anomalous affinities, 172 
 
 Transferred from phlogifton into alcaline 
 Salts, 167,168 
 
 from alcalies into calcareous earths, 
 
 176, n. 
 
 from alcalies into metals, 173, n. 
 from phlogifton into metals, ib. 
 
 Becomes coloured from inflammable mat- 
 ter, 163 
 
 colour how difcharged, 180 
 
 Its habitude to vinous fpirits, 164, 4535^7. 
 
 to Oils, 164 
 
 How it influences fermentation and putre- 
 fadtion, 163 
 
 Produces heat with water and ice, 161 
 Volatilized, 164 
 
 properties of the volatile acid, ib. 
 
 Changed into nitrous acid, 455 
 
 Acidula , 252 
 
 /Ether , its preparation, 454 
 
 Whence it proceeds, 454, 455 
 
 Its chemical characters, ib. 
 
 Nitrous , _ 455 
 
 /Ethiops , Antimonial, 96 
 
 Mineral, ib. 
 
 Agallochum wood, its chemical hiftory, 420 
 yields a concrete Oil, 421 
 
 Agaric of the Larch- tree, 349 
 
 its chemical hiftory, 350 
 
 yields a glutinous fubftance not foluble in 
 water or fpirit, ib. 
 
 Agates 
 
I 
 
 N D E X. 
 
 A gate > ftained black, p. 47, n. 
 
 See Stones. 
 
 Air , fixed in bodies, 473, n. 
 
 extricated from them, 473,474,0. 
 
 transferred from one body into another, ib. 
 Its influence in vegetation, 261, n. 
 
 in fermentation, 441 
 
 in precipitation, 176? n. 
 
 in the production of colours, 63. n. 438, 
 
 510 
 
 in the change of colours, 430,^7. 
 in the deftrucftion of colours, ib. 434 
 Means of changing and renewing in hot- 
 houfes, &c. 262 , n. 
 
 Deftroyed by pafling through fire, 462,0. 
 by fermenting liquors, 440 
 
 Album gracum , 585 
 
 chemical examination, 585, 586 
 
 differences from other ftercora, ib. 
 
 Alcaheji , or univerfal menftruum abfurd, 103 
 Alcohol , fee Spirit of Wine rectified. 
 
 Alcaiies in general, 159 
 
 Their characters, ib. 
 
 Are not the only fubftances which change 
 blue flowers green, s6, n. 
 
 Do not always eftervefce with acids, 47 3, n. 
 Do not always precipitate metals diffolved 
 in acids, 488, n. 
 
 Of different kinds, 159 
 
 Alcaiies , Vegetable fixed , 466 
 
 Produced by fire, 265 
 
 Theory of their production, 471 
 
 Obtained moft plentifully from the moll 
 acid vegetables, 47 1 
 
 from Vinegar, 459 
 
 Method of preparing, 467 
 
 How purified, 467, 470 
 
 Different forts, 468 
 
 differences of the Salts of different plants, 
 
 47 1 , n. 
 
 Their identity in their pure ftate, 470 
 Their general characters, 472 
 
 Ratio in which they increafe the gra- 
 vity of water, 467 
 
 Imbibe vitriolic acid from air, 160 
 
 Combination with different acids, 474 
 Their affinities with acids, 475 
 
 Confidered as menftrua, 473 
 
 Promote the vitrification of earths, 3 ^Jeq. 
 not univerfally, 6, n. 
 
 Contain marine acid, 5 
 
 Diffipated in ftrong fire, 4, n. 
 
 Volatilized in gentle fire, 221, 472, n. 
 Changed into earth and an uninfpiffable 
 fluid, 471 
 
 Alcali, Mineral fixt } p, 159 
 
 Where found, 226, n. 
 
 Obtained from fome vegetables, 468, n. 
 
 from fome animals, 48*5,0. 
 
 Is the bafis of Sea-falt, 215 
 
 Differences from the common vegetable 
 alcaiies, ib. 468. n. 
 
 Alcaiies fixt , caujlic , 
 
 From Antimony and Nitre, 139 
 
 From common fixt alcali and Quick - 
 lime, 473 
 
 Whether they retain any of the Lime, 
 
 191,473,0. 
 
 Their caufticity probably owing to lois of 
 air, ib. 
 
 Corrode fome bodies lefs than fimple 
 Lime-water, 540) n. 
 
 Alcaiies fixt , calcined with animal coals, 476 
 Properties acquired thereby, 476, n. 
 
 Become lefs alealine. 
 
 Precipitate a blue fecula from folution of 
 Iron, ib. 
 
 RedifTolve fundry metals after precipita- 
 tion, ib. 
 
 their agreement and difagreement in this 
 refpecffwith volatile alcaiies, 489, n. 
 
 Alcaiies , volatile , 485 
 
 Produced from vegetable fubftances by 
 putrefaction, 440 
 
 by fire, 463 
 
 from animals by fire, 485 
 
 not in general by putrefaction, 485, n. 
 from fome mineral fubftances, 216,74,65V. 
 How prepared from different animal fub- 
 ftances, 486 
 
 Different ways of purifying them, 487 
 Method of extracting from ammoniacal 
 Salts, 489, 220 
 
 How recovered in a concrete form from 
 their folution or fpirit, 487 
 
 Their identity and diffimilarity, 488 
 Their general properties, ib. 
 
 Not diffoluble in vinous fpirits, 490 
 Solutions in water coagulate with vinous 
 fpirits, ib. 
 
 Precipitate fixt alcaiies from vinous fpi- 
 rits, 224 
 
 Precipitate earths from fixt alcaiies, 5, n. 
 Do not precipitate fome metals from 
 acids, 488, n. 
 
 Rediffolve feveral metals after precipita- 
 tion, 489, n. 
 
 differences from fixt alcaiies as precipi- 
 
 tants for metals, 488, n. 
 
 Alcaiies - 
 
N D E X. 
 
 .Alcalies, volatile, agreement and difagreement 
 with fixt alcalies calcined with phlogi- 
 fton, p. 489, n. 
 
 Contain phlogifton, 491 
 
 Deftroyed by Lime- water, 16, 223 
 
 Do not form a Sope with Oils, 478 
 Alcalies volatile caujlic , their differences from 
 plain alcalies, 222, feq. 
 
 Obtained from Sal ammoniac with me- 
 tallic fubftances, 223 
 
 from Sal ammoniac with Quick-lime, 222 
 from Urine with Quick lime. 578 
 Experiments for determining the phyfical 
 effebt of Lime, 222 
 
 Caufticity, &c. probably owing to their 
 air being abforbed by the Lime, 474, n. 
 By long keeping become fimilar to the 
 plain alcalies, 223 
 
 Alkanet root, 338, n. 
 
 Its hiftory as a colouring drug, 337, n. 
 Its red matter chemically different from 
 all other reds, ib. 
 
 Almonds , fweet , 388 
 
 roafted, a fuccedaneum to Coffee, 378 
 Bitter , 389 
 
 their chemical hiftory, ib. 
 
 their flavouring matter poifonous, ib. 
 Aloes , Gummy-refin, 305 
 
 Chemical hiftory, 306 
 
 Medicinal preparations, ib. 
 
 Glafs ftained by their tinbture, 307 
 
 Althaa , roots and leaves, 335 
 
 Chemical hiftory of, ib. 
 
 Alum , 185 
 
 Hiftory of its ores, ib. 
 
 How prepared in different places, 186 
 Artificially produced, 185, n. 
 
 Its chemical properties, 187 
 
 Analyfis, 188 
 
 Its acid abforbed by vinous fpirits, ib. 
 Its ufes, 189 
 
 Colouring parts of vegetable infufions 
 precipitated by it, 266, n. 
 
 Vegetable colours changed by it, 187, 
 
 43 U/?- 
 
 Amalgamation of metals with Mercury, 93, n. 
 Different methods of effecting, 103 
 
 Of Copper, 65, n. 
 
 Of Regulus of Antimony, 131 
 
 The metals feparated by triture and di- 
 geflion, 93, n. 
 
 Whether any changes produced in the 
 Mercury or metal, ib. 
 
 Amber , a bitumen, 232 
 
 Artificial imitations of, ib. 
 
 5 
 
 Amber , produced from Petroleum and vitrio- 
 lic acid, 233 
 
 Probably generated inftantaneoufly, ib. 
 Different lorts, ib. 
 
 Sophifticated with a vegetable Refin, ib. 
 Coloured and embellifhed by art, 234 
 Clarification of opake forts, ib. 
 
 Hardnefs improved,- ib. 
 
 Its habitude to differentmenftrua, 234,235 
 not totally foluble in any, ib. 
 
 Its analyfis by diftillation, 235 
 
 Salt, how purified, 236 
 
 enquiry into its nature, 236, 237 
 various experiments on, 237, n. 238 n. 
 its acid analogous to vegetable acids, ib. 
 Oil rectified, 238 
 
 made rmfcible with water, &c. 239 
 
 Quantity of Salt and Oil from different 
 forts of Amber, ib. 
 
 Amber varnifh, 235, 236 
 
 Ambergris, a bitumen, 239 
 
 Its chemical characters, 240 
 
 Sophiftications diftinguiftied, ib. 
 
 Totally foluble in Oils, ib. 
 
 in vinous fpirits, 241 
 
 Analyfed by diftillation, ib. 
 
 yields the fame products as Amber, ib. 
 difputes about its analyfis, reconciled, 242 
 Ametbyjl , lofes its colour in the fire, 6, m 
 Amianthus , a fpecies of Talc, 30 
 
 how formed into incombuftible cloth and 
 paper, 30, n. 
 
 Ammoniacal Salts, what, 216 
 
 See Salts. 
 
 Ammoniacum Gummy-refin, 312 
 
 Its chemical hiftory, ib. 
 
 Amomum of the Germans, V. Pimento. 
 Anatomical injections, metallic, 112,95 
 Angelica root, its chemical hiftory, 393 
 Wormeaten roots, their ufe, ib. 
 
 Anil plant, 435 
 
 Method of preparing Indigo from it, ib. 
 See Indigo. 
 
 Animals , chemical hiftory of, 480 
 
 Putrefaction of the juices in living ani- 
 mals, 483 
 
 Production of fat, how promoted and im- 
 peded. 558 
 
 Changes of the aliment in the body, 480 
 Concretion of the fluids into Calculi, 484 
 Milk altered by the aliment. 569 
 
 as alfo Urine. 578 
 
 and the folid parts, 387, 482 
 
 Elegant fkeletons of fmall animals obtain- 
 ed by means of infeCts, 497 
 
 Animal 
 
N D E X. 
 
 Animal fubftances, their natural principles, 
 
 p. 482 
 
 Differences from vegetable fubftances, 483 
 Their difpofttion to putrefy, ib. 
 
 Preferved by Salts, 484, n. 
 
 by camphor, ib. 320 
 
 by vinous fpirits, 484 
 
 by aromatics, bitters, &c. ib. 
 
 by Sugar, 330 
 
 in vitriolic mines, i 82, n. 
 
 Sweetened after putrefa&ion, 484, n. 
 
 Difpofe vegetable fubftances to acid or 
 
 vinous fermentation, ib. 
 
 Their analyfts by fire, 485 
 
 Fats yield different products from the 
 other parts. 559 
 
 Soft parts yield different earths from the 
 hard, 484 
 
 Whether they yield any fixt Alcali, 485,0. 
 Contain acid, 491 
 
 Anime , its chemical hiftory, 296 
 
 Anifeeds , chemical hiftory of, 393 
 
 peculiarities of their effential Oil, 394 
 Anife , Stellated . , ib. 
 
 Chemical hiftory, ib. 
 
 Chemical differences from the common, /A 
 Annotto , how prepared, 433 
 
 Its hiftory as a colouring drug, ib. 
 
 Perifhablenefs of its colour, 434 
 
 Its preparation improved, ib. 
 
 Antihebticum Poterii, 89, 138 
 
 Antimony , its natural hiftory, 1 28 
 
 Compofed of Regulus and common Sul- 
 phur, 129 
 
 Methods of feparating the Regulus, 130 
 Chemical properties of the Regulus. See 
 Regulus. 
 
 Its ufe in purifying Gold, 129 
 
 Its general medical hiftory, 128 
 
 Differences of its medical qualities in dif- 
 ferent ftates, 131 
 
 Extemporaneous vitrification withCawk, 
 
 ib. 
 
 Its Butter, 133 
 
 Calces* 136, 1 37 
 
 Ceruffe, 137 
 
 Cinnabar, 135 
 
 inferior to common Cinnabar, ib. 100 
 Flowers, 135, 220 
 
 Glafs, 136 
 
 Hepar, ib. 
 
 Reguli, 138, 139 
 
 Sulphur, golden, 133 
 
 Ants , obfervations on, p. 497 
 
 How deftroyed, 500 
 
 A Refin found in Ant-hills, 497 
 
 Yield an Oil on expreffion, 499 
 
 Yield an effential Oil, 498 
 
 Yield an acid, 497 
 
 examination of the properties of the acid, 
 
 499, n. 
 
 its analogy with vegetable acids, 500, n. 
 Apples , a fuccedaneum to, in fpring, for cu- 
 linary ufe, 361, n. 
 
 Their juice as a rnenftruutn for Iron, 423 
 Aqua chryfulca , 225 
 
 forth , 206 
 
 How purified, ib. 
 
 napheSy 400 
 
 pugilum , 22 5 
 
 regis, 220 
 
 fapphirina , ib. 
 
 Aquila alba r 99 
 
 Arabic gum t 2 8 2 , n . 
 
 Arbor dianee , 47 
 
 Arcanum tartari, 46 r 
 
 Arcanum duplicaturn , 193, 202 
 
 Archil mofsy a blooming purple prepared 
 from, 438 
 
 A like colour from European moftes, 439 
 Method of trying moftes for purple, ib. 
 Archil prepared , its ufe in dying, - 438 
 
 Its colour, on cloth, deftroyed by air, ib. 
 in liquors, deftroyed by exclufion of air, 
 and recovered by its admiffion, ib. 
 Changed to a durable demifcarlet, ib. 
 Argillaceous earths , their general characters, 
 and habitude to other bodies, 21 
 
 Vitrifications with Salts, 22, n. 
 
 Vitrify with arfenic and microcofmic fait, 
 
 22, n. 
 
 with Chalk, 9, n. 
 
 with calx of Iron, 23, n. 56,11. 
 
 not with Chalk and calx of Iron 
 mixed together, 23, n> 
 
 with Gypfum, 22, n. 
 
 difficultly with calx of Lead, 56, n„ 
 
 As the bafis of earthen wares, 21, n. 
 
 Arnica , leaves and flowers, 356 
 
 Their chemical hiftory, ib. 
 
 Arnica Schweedenfis , 361 
 
 Aromatics , chemical hiftory of, 393 
 
 Their fmell and flavour refide in effential 
 Oil, 268 
 
 The tafte and pungency, of fome, in the 
 
 oil, 
 
 Tinctures, 
 Antopkyllus , 
 
 39 0 ) f e y? 
 
 139 
 
 4!4 
 
 of others, in a fixt gummy-refinous' 
 matter, 4®6, feq. 
 
 Arfenic 3 
 
INDEX. 
 
 Arfenic, its general properties, p. 140 
 
 Diftinguifhed from other bodies by a 
 garlic fmell in the fire, 147 
 
 Not fulphureous, 14° 
 
 Whether l'aline or metallic, ib. 
 
 Made to affume a metallic form, ib. 156 
 DifTolved by water, 14° 
 
 by aetds, fparingly, 14 1 
 
 by alcaline ley, plentifully, ib. 
 
 Phaenomena with different acids, 141 
 with various faline liquors, and metal- 
 lic folutions, ib. 
 
 with Mercury-fublimate, 142 
 
 Extricates the nitrous acid from alcalies 
 and earths, ib. 
 
 not the marine, 143? n - 
 
 the acid, extricated by it from nitre, blue 
 and volatile, ib. 
 
 forms with the alcali of the nitre a neu- 
 tral fait, ib. 
 
 Neutralizes alcaline earths, ib. 
 
 Not expelled from alcalies or earths by 
 ffrong fire in clofe vefTels, ib. 
 
 expelled from them by contadf of burn- 
 ing fuel, ib. 
 
 Fixed, 143, 147 
 
 Vitrified, ib. 
 
 Its effedts on different metals, 143 
 
 Affinity to different metals, 145 
 
 Mechanic ufes, ib. 
 
 Effedts on animals, 145, feq. 
 
 Remedies againft its poifon, 146 
 
 Natural hiffory, 147 
 
 Contained in ores, 148 
 
 Its proper ores, 1 47 
 
 White, how prepared, ib. 
 
 Yellow, 153 
 
 Red, 154 
 
 Arum root, chemical hiffory of, 426 
 
 Its ufe in whitening linen, ib. 
 
 Afa dulcis , fee Benzoine, 
 
 Afa fetida , chemical hiffory of, 312 
 
 Afarum root , 358 
 
 AJbcJlos , 30 
 
 AJhes of animal fubffances, 493 
 
 Of hard parts different from thofe of foft, 
 
 484, n. 
 
 Not vitrefcible, 493 * 494j n* 
 
 AJhes of vegetable fubffances, 478, n. 
 
 Differences from thofe of animals, 494, n. 
 Similar to the earth of purging mineral 
 waters, 478, n. 
 
 Melt into green glafs, 479 
 
 Afphaltum , a bitumen, 242 
 
 Different forts and Sophiffications, 243 
 
 Experiments on, 243 
 
 Its ufes, 244 
 
 Affaying , V. Ores, 
 
 Afrringent vegetables, chemical hiffory, 362 
 Are antifeptic, 484, n. 
 
 Aftringency of fome vegetables extradfed 
 by water and fpirit, 362, 318 
 
 of fome, by fpirit only, 339 
 
 of fome, by water only ; as Acacia. 
 Thofe whofe aftringency is foluble in 
 
 water ftrike a black with chalybeate 
 
 vitriol, 72 
 
 others a green, 72, n. 
 
 Their ufe in tanning, 549, n. 
 
 Give durable dyes, 434 
 
 Ufe in fixing dyes, 386 
 
 Atmojphere , contains water; which is im- 
 bibed by many falts, 160, dsV. 
 
 Contains vitriolic acid, 160 
 
 Contains no nrtre, 198 
 
 nor fulphur, 172 
 
 Diffolves, as a menftruum, the odours of 
 vegetables, 274 
 
 and adtive parts which are not volatile, ib. 
 V. Air. 
 
 Atr amenta, 1 8 r 
 
 Auripigment , 154 
 
 See Orpiment. 
 
 Aurum fulminans , method of preparing, 36 
 Made of a purple colour, 37 
 
 Caufe of its fulmination, 36 
 
 Its fulminating quality deftroyed and re- 
 covered, lb, 
 
 Aurum mofaicum , its preparation, 88 
 
 B. 
 
 T)Alfams, refinous juices, 265 
 
 Their general properties, 283 
 
 How made foluble in water, ib. 
 
 Of Copaiba , 285 
 
 its chemical differences from other 
 balfams, ib. 
 
 yields a blue oil, 285, n. 
 
 Of Gilead, 283 
 
 its chemical hiftory, 283, 284, n. 
 its ufe as a cofmetic, ib. 
 
 Qi Peru, 285 
 
 different forts, 286 
 
 chemical hiftory and difference from 
 other refins, ib. 
 
 not mifcible with expreffed oils. ib. 
 yields an effential fait by d iff illation, ib. 
 Of Tolu, 284 
 
 chemical hiftory, 285, n. 
 
 yields an effential fait by diftillation, ib. 
 
 Balfams, 
 
N D E X. 
 
 Balfams odoriferous, 
 Spirituous, 
 
 Of Sulphur, 
 
 with diftilled oils, 
 Barbadoes tar, 
 
 404 
 267 
 168, 169 
 169 
 231 
 
 Barks , fometimes more odorous than the 
 wood, 418, 419 
 
 fometimes lefs fo, 417 
 
 fometimes their odour confined to a thin 
 membrane next the wood, 402 
 
 Made into cloth, 428, n. 
 
 Baurach, 227 
 
 Bdellium , chemical hi (lory of, 313 
 
 Bee- glue, 332 
 
 Beef, analyfed, 550 
 
 Beesy fubftances agreeable to, 330 
 
 Subftances offenfive to, ib . 
 
 Said to fly from the herb feverfew, 421 
 Contain an acid juice, 498 
 
 Beet roots, fugar extraded from, 328, n. 
 Ben nuts, their oil, 323 
 
 Its excellence for perfumes, ib. 278 
 
 Bell-metal , 66 
 
 Benzoine, refin, 292 
 
 chemical hiftory, ib. 
 
 Its flowers or efiential fait how prepared, 
 
 293 
 
 A fimilar fait from other fubftances, 285, 
 
 n. 286, 291 
 
 Its ufe in perfumes, and as a cofmetic, 
 
 29 3> 2 94 
 
 Berg-gruriy 11"] 
 
 Betony , chemical hiftory of, 398 
 
 Bezoar, occidental, 537 
 
 Oriental, 533 
 
 Its fuppofed produdion, ib. 
 
 Not a natural concrete, 534 
 
 Different faditious forts, 535 
 
 Analyfed by menftrua and fire, 535,_/ry. 
 Bezoar dies, 533 
 
 Bezoardic fpirit of nitre, 1 34 
 
 Bezoar dicum j aviate, 89 
 
 Minerale, &c. 1 34 
 
 Bile , its ufe in the body, 566 
 
 Its qualities, 567 
 
 See Gall. 
 
 Birthworty different forts, 406 
 
 Chemical hiftory, 407 
 
 Bifmuthy its general properties, 106 
 
 Its great fufibility and vitrefeibility, ib. 
 Its calces eafily revived, 107 
 
 Solution in aqua fortis, ib. 
 
 turns the red dye of madder to crimfon 
 and purple, 388 
 
 Magiftery, its preparation, 107 
 
 various obfervations and experiments 
 on, ib.feq. 
 
 inconveniences as a cofmetic, 108 
 ftains hair of a dark colour, ib. 
 
 Combination with the marine acid, 109 
 pearl coloured powder, ib. 
 
 Its habitude to other acids, 109 
 
 Diflolved in alcalies, 107, n. 
 
 Effeds of fulphur on it, 109 
 
 remarkable habitude of fulphurated bif- 
 muth to other metals, no 
 
 Effeds of pure bifinuth on different me- 
 tals, no 
 
 Its ufes, nr 
 
 Medical hiftory, 112 
 
 Counterfeited, 113 
 
 Its ores, ib. 
 
 method of allaying and fmeltmg, ib. 
 experiments on, 114 
 
 yield a blue glafs, ib. 
 
 a variable-coloured tindure, ib. 
 
 Bifire , 466 
 
 Bittern of fea-water, 211, n. 212 
 
 Salt extraded from it, ib. 
 
 See Salt, bitter purging. 
 
 Bitter vegetables, chemical hiftory of, 363, 
 
 407 
 
 Bitternefs extraded both by water and 
 fpirit, ib. 
 
 does not arife in diftillation, 274 
 
 freed from fmell by codion with water, 
 
 280, 364 
 
 covered by acids, 449 
 
 Bitumens , 2 30 
 
 Whether of vegetable origin, 283, n. 
 
 General hiftory of, 230 ,fcq. 
 
 Liquid, ib. 
 
 Solid, 231 
 
 A white marine Bitumen, 242, n. 
 
 its chemical hiftory, ib. 
 
 Specific gravities of feveral, ib. 
 
 Their ufes as Pitch, Mor ter, £sV. 231, 244 
 Bitumen Babylonicum , 242 
 
 fudaicum , ib. 
 
 Black, from vegetable aftringents and Cha- 
 lybeate Vitriol, 72 
 
 Dye, 18 1 
 
 improved, 385 
 
 Stain for wood, &c. ib. 
 
 for hair, ftones, &c. 46 
 
 Ivory-black, 325 
 
 Lamp-black, 289 
 
 Bleaching , ufe of Arum root in, 426 
 
 Effeds of Ley and Lime-water, 540 
 Effed of acids. 
 
 G 
 
 Vitriolic 
 
I N 
 
 D 
 
 Vitriolic acid fubftituted to the acid of 
 
 Milk, 573, n. 
 
 Blood, experiments on, 551, n. 
 
 Separation into diffimilar parts, ib. 
 
 Analyfis by fire, 551 
 
 Contains marine Salt, ib. 492 
 
 Blue colour of flowers perifhable, 430 
 
 of fome, extradited by water, ib. 
 
 of none, by fpirit, ib. 
 
 of fome, by no menftruum, 431 
 
 Changed red by acids, ib. 
 
 by fome compound Salts, 187, n. 
 
 White by volatile vitriolic acid, 164, n. 
 Green by alcalies, 431 
 
 by fome compound Salts, 16, n. 
 
 by Lime-water, ib. 
 
 Blue from fubjeCLs of other colours. 
 
 Feculae from green leaves by putrefaction, 
 
 435> 438 
 
 their colour permanent, ib. 
 
 See Indigo and Woad. 
 
 Infufion of brown Nephritic-wood, 385 
 bluenefs deftroyed by acids, ib. 
 
 recovered by alcalies, ib. 
 
 Oils, effential from Milfoil, 409 
 
 from Camomile, 408 
 
 from Pimpinella nigra, 409 
 
 of Thyme digefted with volatile fpirits, 
 
 439 
 
 Oils ernpyreumatic, from Galbanum,3i4 
 from balfam of Copaiba, 285, n. 
 
 their colour perifhable in the air, 408 
 Precipitate of Iron by animal phlogifton, 
 
 72 
 
 See Pruffian-blue. 
 
 Vinous fpirit, diftilled, from Pimpinella 
 nigra, 409 
 
 Blue Dye, with Indigo, 435 
 
 with W oad, 438 
 
 with Pruffian-blue, 73, n. 
 
 Saxon, 437 
 
 Stain for Linen, 436 
 
 for Leather, ib. 
 
 for Glafs ; from Copper, 67 
 
 from Cobalt, 150 
 
 from Iron, 69, n. 
 
 Boar's-tufk anaiyfed, 521 
 
 Boiling heat , the greateft that liquids are fu- 
 fceptible of, 255 
 
 differs according to the weight of the at- 
 
 O <0 
 
 mofphere, &c. 255, n. 
 
 Bole Armenic, 21 
 
 Red, 24 
 
 White, ib. 
 
 experiments on, ik. 
 
 19 
 
 20 
 ib. n. 
 
 516 
 387 
 
 517 
 ib. 
 
 5J9> n- 
 5G 
 519, n. 
 33»n. 
 66 
 
 518 
 ib. 
 
 E X. 
 
 Bolognian ffone, 
 
 Bhofphorus, 
 
 Artificial, 
 
 Bones , carious, whence, 
 made red by aliment. 
 
 Bone, hardened. 
 
 Softened, 
 
 Made fonorous like ffone, 
 
 Whitened, 
 
 Stained black, 
 
 Purple, 
 
 Green, 
 
 Petrefied, 
 
 Ufes, 
 
 Calcination, 
 
 General analyfis, ib. 
 
 Examination of different bony fubffances, 
 
 5 J 9 
 
 Wherein different from horn, 51 r, 516 
 Borax, hiftory of, 226 
 
 Enquiry into its origin and compofition, 
 226, n. 227, n. 
 Confiffs of mineral Alcali and fedative 
 Salt, 227, n. 
 
 See fedative Salt. 
 
 Refining of, 227 
 
 Artificially producible, 227, 228 
 
 Its chemical characters, 228 
 
 Precipitates fundry acid folutions, ib. 
 and fome alcaline ones, ib. 
 
 Tinges flame green, 228, n. 
 
 Appears glutinous in diffolution, 227, n. 
 Habitude to fire, 228 
 
 Ule as a flux, &c. 229 
 
 Makes coloured metals pale, ib. 
 
 Brains, anaiyfed, 560 
 
 Chemical differences from fats, ib. 
 
 Brandy , French , ftrikes a blue colour with 
 Chalybeate folutions, 73 
 
 Other fpirits made to give the fame ap- 
 pearance, ib. 
 
 Its flavour imitated, 455 
 
 Brafs, how made, 65, 123 
 
 Obfervations on the procels, 65, n. 
 
 Its general properties, and differences 
 from Copper, ib. 
 
 Brazil wood, 386 
 
 Its chemical differences from Red-faun- 
 ders, ib. 
 
 Hiftory as a colouring drug, ib. 
 
 Made to afford durable colours, ib. 
 
 Brick earths, 23, n, 
 
 Brimjlone , fee Sulphur. 
 
 Bronze , 1 20 
 
 Its duCtility improved, 121 
 
 Brown 
 
I 
 
 N 
 
 D E X. 
 
 Brown dye from Soot, 466 
 
 Bryony root, 35 1 
 
 Chemical hiftory of, 352 
 
 Buckthorn berries, , 433 
 
 Pigments obtained from, ib. 
 
 Their ufe in dying, ib. 
 
 Burdock root, chemical hiftory of, 383 
 
 Burnet Saxifrage root, chemical hiftory of, 
 
 341 
 
 Butter, examined by menftrua, 571 
 
 Analyfed by fire, ib. 
 
 Butter of Antimony, 133 
 
 Of Arfenic, 142 
 
 Of Bifmuth, 109 
 
 C 
 
 B B A G E red , a faccharine fubftance 
 from, 328, n. 
 
 Cadmia fornacum, 123 
 
 botryites , zonites, & c. 1 27 
 
 Calamine , its hiftory, 123 
 
 Preparation for making Brafs, ib. 
 
 An ore of Zinc, ib. 
 
 Quantity of Zinc contained in it, 124, n. 
 Various experiments on, by menftrua, 124 
 by diftillation, 125 
 
 Medical hiftory, 128 
 
 Calamus aromaticus root, 4 1 0 
 
 Chemical hiftory of, ib. 
 
 Calcareous earths , animal, 540 
 
 Differences from the mineral, ib. 493, n. 
 Afford a ftronger Lime, 540 
 
 Not vitrefcible, 493, n. 
 
 Calcareous earths , mineral, 8 
 
 Their characters, ib. 
 
 Lots of weight in calcination, 10 
 
 Vitrification, 9 
 
 with fome Salts vitrefy more eafily than 
 the cryftaBine, 9, n. 
 
 with others more difficultly, ib. 
 
 vitrefy with Clay, 9, n. 
 
 with ftony matters of ores, 10, n. 
 
 Yield a Phofphorus with marine acid, 
 
 16, n. 226 
 
 with the nitrous, 9 
 
 Volatilized by the nitrous acid, 17, n. 
 
 by volatile Salts, 221, n. 
 
 Not Voluble in the vitriolic acid, 8 
 
 precipitated by it from others, ib. 
 
 form with it Gypfum or Selenites, ib. 
 
 i9» n * 
 
 Calcination of metals, 53 
 
 Increafe of weight in calcination, 56 
 
 Calculi animal, their production, 484 
 
 Different kinds, 534 
 
 Calculus humannsy 332, n. 
 
 Enquiry into fol vents for it, t;33> n. 
 
 Callico , fee Linen. 
 
 Calomel, 99 
 
 Camomile flowers, 408 
 
 Their chemical hiftory and analyfis, ib. 
 Contain a faline matter, ib. 
 
 Yield a blue Oil, ib. 
 
 Their great antifeptic power, 484,0. 
 Campeachy wood, fee Logwood. 
 
 Camphor , 3 * 8 
 
 Obtained from different plants, 277 
 
 Method of preparing, 3 1 9 
 
 How refined by fublimation, ib. 
 
 by folution in fpirit, 320, n. 
 
 Its general properties, 319 
 
 How diftinguiihed from coagulated Oils, 
 Reffns, (Ac. 
 
 Its folution in different menftrua, 
 
 Oils by diftillation, 
 
 Ufe in varnifhes, (Ac. 
 
 Fitted for medicinal exhibition, 
 
 Cancamum , Refin, 
 
 Cantharides , chemical hiftory of, 
 
 Analyfis, 
 
 Their aCtive principle. 
 
 Carat weights. 
 
 Cardamom-feeds , lejfer , 
 
 Analyfis of the feeds and hulks, 
 
 Larger , how they differ from the 
 Carduus benedidius , its analyfis. 
 
 Its eflential Salt, 
 
 Car line thijlle, chemical hiftory of, 
 
 Carob, its chemical hiftory, 
 
 Carp-Jlone , analyfed, 
 
 Carpobalfam, 
 
 Carthamus , 
 
 V. Safflower. 
 
 Cafe - bar deni ng of Iron, 
 
 Cafia fiflularis, its chemical hiftory, 
 
 Lignea , its agreement and difagreement 
 with Cinnamon, 403 
 
 Caffidony flowers, their chemical hiftory, 372 
 
 Caflor , hiftory of, 565 
 
 Its fophiftications, ib . 
 
 Analyfed, 566 
 
 Cauflic Alcali with Quick-lime, 473 
 
 Alcali from Nitre and Antimony, 139 
 Antimonial Butter, 133 
 
 Lunar, 47 
 
 Cawke, 131,11. 
 
 Extemporaneous vitrification of Anti- 
 mony with it, ib. 
 
 Celeri , Sugar from, 328, n. 
 
 Cements , - 14, n. 
 
 4 G 2 Cement r. 
 
 265 
 
 320 
 
 321 
 320 
 
 322 
 296 
 
 494 
 
 496 
 
 ib. 
 
 41 
 
 401 
 
 402 
 fmal ],ib. 
 
 3 6 5 
 
 366 
 
 405 
 
 424 
 
 525 
 
 284 
 
 43 2 
 
 79, n. 
 424 
 
N D E X. 
 
 Cements, for water-works, 
 Bituminous, 
 
 58, n. 
 244 
 
 A [Irons; one for earthen- ware, &c. 573, n. 
 Centaury , herb, 365 
 
 Its chemical hiftory, ib. 
 
 Ceruffe, how made, 58, n - 
 
 Ceruffe of Antimony, 1 37 
 
 Chalcanthum , 1 8 1 
 
 Chalcedony , ftained black, 46, n. 
 
 ■Chalk , its hiftorv and ufes, 8, 1 r 
 
 Various experiments on, ib. 
 
 Experiments on ftones found in Chalk- 
 pits, 1 1 
 
 Chalk , French , 26 
 
 Charcoal , its preparation, 463, n. 
 
 D iu'erences as fuel, and for other ufes, ib. 
 Pernicious effeCts when burnt in clofe 
 
 ib. 
 
 572 
 
 ib. 
 
 rooms, whence, 
 
 Cheefe , examined by menftrua, 
 Analyfed by fire, 
 
 Has more of an animal nature than But- 
 
 ib. 
 
 573 » n - 
 282 
 
 398 
 18, n. 
 381, 382 
 381 
 227 
 
 ter, 
 
 Forms a ftrong cement, 
 
 Cherry- tree (Jum, 
 
 Chervil, its chemical hiftory, 
 China-ware , its ingredients, 
 China-root, its hiftory, 
 
 Dutch method of fophifticating it 
 Chryfocolla , 
 
 Cicnta aquettioa, its refemblance to fmallage. 
 
 How diftinguilhed. 
 
 395 
 
 396 
 
 Its poifouous nature. 
 
 ib. 
 
 Remedies, 
 
 ib. 
 
 Analyfis, 
 
 397 
 
 Cinas fernen , 
 
 3°6 
 
 Cinnabar , of Antimony , 
 
 i 35 
 
 how it differs from factitious, 
 
 1 01, 135 
 
 Factitious , manner of making. 
 
 xoo 
 
 made without fublimation. 
 
 101 , n. 
 
 ground by the Dutch with additions, 102 
 Native, its different kinds, 105 
 
 purified by fublimation, ib. 
 
 method of improving the colour of 
 blackifh forts, 106 
 
 proportion of Mercury and Sulphur, ib. 
 W hitened by Oil of V itrioi, 1 c6 
 
 Revival of Mercury from, 1.05 
 
 fucceeds better with metals than with 
 
 Alcali, 
 
 Cinnamon , its chemical hiftory, 
 Gijlus laclanifera,. 
 
 Civet, its hiftory and properties, 
 
 95 
 402 
 
 2-95 
 562 
 
 How ufed to advantage in perfumes, 563 
 Clarification of liquors with eggs,. 554 - 
 
 554 
 211, 328 
 23, n. 
 22, n. 
 ib. 
 
 Clarification with Ifinglafs, 
 
 With blood. 
 
 Clay, its different kinds, 
 
 Its vitrification with Salts, 
 with other earths. 
 
 Its habitude to different earths with re- 
 gard to making veffels, 21, n. 
 
 Cloth , from different vegetables, 428, 429 
 Differences of vegetable and animal in 
 receiving colours, 429 
 
 in beingcorroded by certain liquors, 540 
 Incombuftible from Afbeftos, 30 
 
 Clouds, artificial, jg^ 
 
 Cloves, natural and chemical hiftory of, 412 
 Their effential Oil, mild, 413 
 
 Pungency refides in the Refin, ib. 
 
 Clyfji of Antimony, 134 
 
 Coagulation of liquids by mixture, 4, q, 226 
 Coal of animal fubftances, its difference 
 from that of vegetables, 493 
 
 Differences of thofe of different vege- 
 tables, 463^ n. 
 
 Cobalt , its general hiftory, 148 
 
 Saxon, 149, n. 
 
 Englifh, ib. 
 
 Chinefe, ib. 
 
 Method of manufacturing in Saxony, 150, 
 
 151 
 
 Its riebnefs how eftimated, 152 
 
 Its chemical hiftory, ib. 
 
 Flow diftinguifhedfrom other minerals, ib. 
 Is an ore of a peculiar femimetal, fee Re~ 
 gulus of Cobalt. 
 
 Smalt from Englilh Cobalt, 152 
 
 Coecognidium , its chemical hiftory, 344 
 Cocadus Indus , its chemical hiftory, 345 
 Coccus Polonicus, 309 
 
 Its hiftory as a colouring drug, ib. 
 
 Cochineal , general hiftory of, 503 
 
 Different forts, 504 
 
 Its hiftory as a colouring drug, 505 
 See Crim/on , Scarlet. 
 
 Refiduum after dying with it, applied to 
 
 _ ul D . 507 
 
 Coffee, its chemical hiftory, 378 
 
 receives its flavour from roafting, 379 
 Subftitutes, 378 
 
 Cohobation of diftilled waters, enquiry whe- 
 ther ufeful, 276, n. 
 
 Cold, artificial production of, 196, 218, 255 
 in certain tircumftances expands me- 
 tals, 69, n. 
 
 Colophony 287 
 Coloquintida, its hiftory, 351 
 
 Colours, produced by mixture, 63,11.. 181, &c. 
 
 Colours 3 
 
N D E X. 
 
 Colours, changed by mixture, 431, feq. 
 
 deftroved by mixture, 63, n. 194, n. 
 produced by air, 639, n. 438, 5x0 
 
 changed by air, 430, f e <l- 
 
 defiroyed by air, ib. 434 
 
 Of one liquor different when cold and 
 warm, 1 14, 153. 
 
 Different ones fucceffively in one liquor 
 after fhaking, 81,11. 
 
 Colouring. Matter , of vegetables and ani- 
 mals, 430, Or. 
 
 Soluble in fpirit and in water, 384 
 
 in 1 pint, not in water, 
 in water, not in fpirit, 
 iiirno menftiU tm, 
 
 434? 299 
 43° 
 43 1 
 
 Recovered from folutious in form of an 
 indifloluble lake 266 
 
 See Blue, Red, OV. 
 
 Comfry , chemical hiftcry of, 335 
 
 Contraction , of Metals by heat, 69, n. 
 
 Contrayerva , chemical hifiory, 367 
 
 Contrefait , x 1 5 
 
 Coped, its characters, 299, n. 
 
 Solution for vurnithes, ib. 
 
 Copper, its general characters, 61 
 
 phenomena in the fire, ib. 62 
 
 tals, 
 
 How granulated 
 Vitrification in the tolar heat, 
 not vitrefcible by culinary fire, 
 vitrifies with certain earths, 
 Amalgamation, 
 
 Habitude to different Metals, 65, 66 
 
 57? n - 
 
 made yellow by zinc, 120 
 
 whitened by arfenic, 66, 145 
 
 white Japan copper, 66, n. 
 
 reduced into red, ib. 
 
 Its fpecific gravity increafed by mixture 
 of a lighter Metal, ib. 
 
 Solubility in different liquors, 62 
 
 phaenomena with different acids, ib. 
 diffolved by volatile alcali, 62, n. 63 
 contained in waters, 
 
 leaft deftruCtible of the imperfect Me- 
 
 6r, n. 
 62 
 ib. 
 ib. 
 6, n. 
 6 5 
 
 Ui'es in painting and itaining, 
 colours it communicates to gla 
 heightens the colour of gold, 
 
 and filver brittle, 
 Its ores, 
 
 Copperas , 1 g r 
 
 Copperas Stones, their chemical hifiory, 174 
 Coral, an animal produ&ion, 544 
 
 Artificial imitations of, 554c 
 
 difiinguilhed, ib. 
 
 Solubility in acids, ib. 
 
 Extraction of the red colour, 545, 546. 
 Coralline, an animal production, 546 
 
 Analylis, tb 
 
 Cork , its chemical hifiory, 427 
 
 Colours it communicates to different li- 
 quors, 428 
 
 Cofmetic , preparation of Gall, 568 
 
 White preparations of Tin, 88 
 
 Magiftery of Bifmuth, 107 
 
 ill confequences of its uie ic8 
 
 Milky folution of opobalfam, 284 
 
 of benzoine, 294 
 
 Cotton , hifiory and analyfi?, 428 
 
 different kinds, 430 
 
 Flax made to referable it, 428, n. 
 
 Crab's Claws , analyfed, 542 
 
 Crab's Eyes , chemical hifiory of, 538 
 
 Cranium humanum, analyfed, 521 
 
 Crimfon , dye, with cochineal, 505, n. 
 
 improved, ib. 
 
 with Madder, 388 
 
 Lake from Brazil wood, 386 
 
 Tranfparent for water colours, ib. 
 
 Crocus metdllorum, 137 
 
 Crucibles , Heffian and black Lead, their 
 different qualities, 22, n. 
 
 Principles for making, 21, n. 22, n. 
 Ufe of lining them with borax, 229 
 
 Cryjlal, 6 
 
 Experiments on, 7 
 
 How tinged of various colours,"' ib. 
 
 Cryjlalline Earth , its characters, 2 
 
 Diffolved in alcaline ley, 4 
 
 Precipitated from fixt alcalies by volatile, 
 
 5,11. 
 
 Made foluble in acids, ib. 
 
 Its vitrification with Salts, 3 
 
 with earths, 6, n. 
 
 68 
 
 promoted by fome metallic calces, as 
 
 1, n. 
 
 iron, 
 
 56, n. 
 
 66 
 
 impeded by others, as lead, 
 
 ib. 
 
 7? n. 
 
 CryJlalli%atlon of Salts, 
 
 2^6 
 
 43 
 
 by cold, 
 
 ib. 
 
 gold 
 
 by heat, ib. 279, 
 
 329, n. 
 
 :? 51 
 
 promoted by vinous fpirits, 
 
 258 
 
 67 
 
 Cryjlallus mineralis , 
 
 202 
 
 ore, 
 
 Cubebs , their chemical hifiory, 
 
 417 
 
 , 68 
 
 Cupels ,, 
 
INDEX. 
 
 Cupels , - 40. n. 
 
 Cupellation of Gold and Silver with Lead, 41 
 Advantages of Bifmuth above Lead, 106, 
 
 1 12 
 
 Cuttle bone , hiftory and analyfis, 539 
 
 Gyanus flowers, chemical hiftory of their 
 colour, 
 
 Not extra&ed by any menftruum, 
 
 Cyperus root , oriental and European, 
 Analyfed, 
 
 Genuine diftinguifhed, 
 Its charafters, 
 
 Its ufe in ftaining, 
 Drajiic vegetables, made 
 
 431 
 
 ib. 
 
 410 
 
 ib. 
 
 D 
 
 A M P S, in mines, artificial vapour 
 fimilar to, 70, n. 
 
 Deco A ions, 267 
 
 General obfervations on, ib. 
 
 Alterations made by long boiling, 268 
 
 Depilatories, i 55 > 158 
 
 Dew, 248 
 
 Diamonds, alterations they undergo in the 
 fire, 6, n. 
 
 Digejlor, 517 
 
 Diphryges, 127 
 
 Diftillation of liquors, expedited, 251, n. 
 
 Of fimple waters and fpirits, 273, 277 
 W ater elevates the odorous parts of Ve- 
 getables, 268 
 
 and of animals, 482 
 
 the acrimony of fome vegetables, 390 
 
 Jeq. 
 
 not of others, p ) \o,feq. 
 
 the warmth of fome aromatics, 393, feq. 
 not of others, 41 1, feq. 
 
 Spirit elevates the odorous parts of fome 
 vegetables,, 277 
 
 not of others, ib. 
 
 nor of animal fubftances, 564, 566 
 Greater heat required for the diftillation 
 of odours, than for their exhalation in 
 open air, 274, n. 275, n. 
 
 Principles exhalable in the air, not di- 
 ftiliable, ib. 
 
 Diftillation of folicl parts of animals per fe,486 
 of vegetables, 462 
 
 Extrication of elaftic vapours in the 
 procefs, 486, 464 
 
 Danger of burfting the veffels, how pre- 
 vented, ib. 
 
 Dittany of Crete, its hiftory, 399 
 
 White , its hiftory, 364 
 
 Its effluvia inflammable, ib. n. 
 
 j Doromcum, its hiftory, 370 
 
 Draco fortifcaius, 20 1 
 
 Mitigatus, 99 
 
 Dragon’s Blood, its forts and preparation, 299 
 
 299 
 ib. 
 
 299, 300, n. 
 mild by boiling, 
 268 
 
 Inconveniences thereof, 268, n. 
 
 Ductility of metals into wire, not propor- 
 tionable to their extendibility into 
 leaf, 85, n. 
 
 Dyes, of aftringent fubftances durable, 434 
 Perifhable ones fixed by aftringents, 386 
 Dying, fee Blue, Red. &c. 
 
 Tft A R T HY fubftances, common divi- 
 •*—* fions of them fuperficial, 1 
 
 Chemical diftribution of them, 2 
 
 All unfufible when pure, ib. 
 
 Mixtures of two or more fufible, ib. 
 
 494, n. 
 
 except of animal earths. 
 The more fimple earths : 
 Argillaceous and aluminous , 
 Calcareous , mineral, 
 animal, 
 
 Cryftalline , 
 
 7 alky. 
 
 Vegetable and magnefta, 2 04, 
 AJhes of foft parts of animals, 
 AJhcs of bones and horns. 
 Vegetable and animal mould, 
 Gypfeous earthy concretes, 
 
 21, 185 
 8 
 
 540 
 
 2 
 
 27 
 
 203, n. 478 
 494, n. 
 ib. 
 
 ib. 475, n. 
 18 
 
 See Argillaceous , Calcareous, &c 
 Earth from water, 259 
 
 From rectified fpirit of wine and mineral 
 
 acids, 454, 455 
 
 Earth, as a foil for vegetables, 261, n. 
 
 Its different kinds, ib. 
 
 each adapted to peculiar plants, ib. 
 
 Its office to vegetables, 262, n. 
 
 Earthquakes, artificial, 73 
 
 Earth-worms, as food for birds, 500, n. 
 
 Chemical hiftory of, 500 
 
 Efflervefcence of alcalies with acids, to what 
 owing, 473, n. 
 
 Alcalies prepared fo as to make no effer- 
 vefcence, ib. 
 
 Effluvia of vegetables, are their adfive parts 
 diffolved in air, - 274, 275, n. 
 
 Contain principles incapable of arifing in 
 diftillation, ib. 
 
 Their diffolution in air promoted by hu- 
 midity, 274, n. 
 
 Inflammable from certain vegetables, 365 
 Eggs, experiments of coroding and difi’olving 
 the fhell, 543 
 
 Per- 
 
D E X. 
 
 N 
 
 Perfpirability of the Ihell, 556 
 
 Lofs of weight in keeping, in different 
 circumftances, 557, n. 
 
 Prefervation, ib. 
 
 Hatching by artificial heat, ib. 
 
 unheeded caufes of failure, ib. 
 
 Proportion of the white, yolk, lAc. 556 
 White, its nature, 554 
 
 how aft’eCted by different admixtures, 555 
 changed into a lubltance like Amber,554 
 lofs of weight in drying, &c. ib. 
 
 boiled hard, liquifies in the air, 555 
 analyfed, 554 
 
 Yolk, how affeCted by different admix- 
 tures, _ 556 
 
 lofs in drying, &c. ib. 
 
 boiled hard, yields an oil on expref- 
 iion, ib. 
 
 renders refinous fubftances foluble in 
 water, 283 
 
 analyfed, 556 
 
 Shells, analyfis and ufes, 542, 543 
 
 Elceofacchara , 409 
 
 Elecampane root, its chemical hiffory, 420 
 Yields a concrete effential oil, ib. 
 
 Elemi , refin, 296 
 
 Chemical hiftory, ib. 
 
 Elixirs , 267 
 
 Elkshoof, analyfed, 514 
 
 Emerald , lofes its colour in the fire, 6, n. 
 Tinges the flame bluifh, ib. 
 
 Stained black, 46, n. 
 
 Emery , 80 
 
 Different forts and ufes, 80, 81 
 
 Various experiments on, 81, 82 
 
 Spanifh, ufed for augmenting Gold, 82 
 fufpeCtec! to be, or to contain, platina, 
 
 44 
 
 Emulfions , 389 
 
 Enamels , or glaffes femivitrified, 85, n. 
 
 Their bafis, unfufible calx of Tin, ib. 88 
 Colours for, V. Glafs, 
 
 E (fences from vegetables, 267 
 
 Ether , V. /Ether. 
 
 Evaporation promoted by blowing air through 
 the liquor, 251, n. 
 
 Euphorbiv.m plants, 30 x 
 
 Gummy-refm , its hiftory, 302 
 
 Excrements- animal , 585 
 
 Expanfion of metals from cold, 69, n. 
 
 Extracts, watery and fpiritous, 268 
 
 Watery, how obtained free from refin, ib. 
 
 fpirituous, free from gum. 
 
 ib. 
 
 method of preserving evaporable parts, 
 
 275, n. 
 
 F 
 
 Jf'A B A St . Ignaiii, chemical hiftory of, 
 
 _ 346 
 
 Farina , yellow, of the flowers of plants, 
 peculiarity of its colouring matter, 432 
 Eats, their production, 558 
 
 Different kinds, ib. 
 
 Prefervation, ib. 
 
 Purification, ib. 
 
 Habitude to menftrua, 559 
 
 Analyfis of feveral forts, ib. 
 
 Feathers ftained purple, 33, n. 
 
 See Bone , 
 
 Analyfed, 549 
 
 Febrifnguni Craanii , 138 
 
 Fennel, common and fvveet, 397, 398 
 
 Chemical differences of the feeds* 398 
 Analyfis of the feeds and leaves, 397 
 Seeds give green tincture to Spirit, ib. 
 Fenugreek feed, hiftory and analyfis,. 335 
 Fermentation, its phenomena, 440 
 
 Its three ftages, and their produCts, ib. 
 Subjedts of vinous fermentation, vege- 
 table fweets, 448 
 
 How impeded and promoted, 441 
 
 Vinous *and acetous excited by animal 
 matters, 484, n. 
 
 promoted by jalap, 353 
 
 Variations produced by different ferments, 
 
 448 
 
 and by other aditions, 449 
 
 ACtive powers of l'ome vegetables inde- 
 ftruCtible by fermentation, 460 
 
 increased by fermentation, 449 
 
 Feverfew leaves, chemical hiftory, 421 
 Figivort root, its chemical hiftory, 370 
 Filings of metals may abrade and retain 
 fomewhat from the file, 117 
 
 Fining of liquors by blood, 21 1, 328 
 
 By Ichthycolla, 554 
 
 By whites of Eggs, ib. 
 
 Fire , produced from the mixture of cold 
 liquors, 195 
 
 Supported without air, 201 
 
 Does not always expand bodies, 69, n. 
 Fifo, a bait for, 573 
 
 Pellets for ftupifying, 345 
 
 Analyfed, 551 
 
 Fifh-glue , fee Ichtbyocolla. 
 
 Fixed-bodies volatilized : 
 
 Earth by water, 259 
 
 Vitriolated tartar by water, 247 
 
 Fixed alcaline Salt by fpirit of wine, 451 
 by volatile alcali, 221 
 
 Calcareous 
 
I N D 
 
 Calcareous earth, by volatile alcali, 
 
 222, n. 
 
 by nitrous acid, 17, n. 
 
 Metals by marine acid, 208 
 
 Flame , from mixture of cold liquors, 195 
 'Finged green, 227 , 228 
 
 Tinged blue and green, 62 
 
 Whitened, 68, n. 
 
 Making the face like a corps, 1 15 
 
 Flax made to referable cotton, 428, n. 
 
 Subftitutes for it, ib. 429, n. 
 
 Flejb, its nutritious matter, 550 
 
 how extracted, ib. 
 
 Preferved from putrefaction, 484 
 
 Made red by nitre, 201 
 
 Sweetened after putrefaction, 484 
 
 Analyfed, 550 
 
 Fliegenjlein , 149 
 
 Flint , 2 
 
 Various experiments on, 3, feq. 
 
 Made foluble in water, 4 
 
 Made foluble in acids, 5, n. 
 
 Contains vitriolic acid, ib. 
 
 Made luminous in the dark, 3 
 
 Vitrification, 3, 4 
 
 Affords clearer glafs than fand, 4, n. 
 
 Flint glafs, ufe of Lead in its compofition, 4 
 Lead reviv’d from, 55, n. 
 
 Penetrated by vapours, ib. 
 
 Flores martiales , 71, 219 
 
 Flowers of Antimony, 135, 220 
 
 Bifmuth, 1 13 
 
 Cobalt, 149 
 
 Copper, 220 
 
 Steel, 219 
 
 Flowers of Vegetables, chemical hiftory of their 
 
 colours, 
 
 43 © 
 
 Blue, 
 
 ib. 
 
 Orange, 
 
 432 
 
 Purple, 
 
 431 
 
 Red, 
 
 lb. 
 
 White, 
 
 432 
 
 Yellow, 
 
 43 1 
 
 See the refpedlive colours. 
 
 Their fmell tometimes confined 
 
 to the 
 
 cups, 400 
 
 Flux, biack, 203 
 
 Foils for Specula, 88, 95, 1x1 
 
 French berries, 433 
 
 Fruits , chemical hiflory of their colour, 432 
 
 Cryftalline fait from the juices of acid 
 
 ones, 423, n. 
 
 Fumes condenfing in the air into a cloud, 
 
 195 
 
 E X. 
 
 Inflammable in the diffolution of Metals, 
 
 70, 11 7 
 
 Fumus rubeus alchemjlarum , " 134 
 
 Furnaces , commodious portable ones from 
 black-lead pots, or other earthy com- 
 pofitions, • 22 
 
 Fufibility , of two fubftances mixed, greater 
 than of either feparately, 1 1 1 
 
 lefs than of either feparately, 57 
 
 Subftances unfufible feparately, fufible 
 in mixture, 9, n. 
 
 Fujlet, 384, n. 
 
 Its qualities as a dying drug, 284, 28 c 
 Fujlick wood, 384; n. 
 
 Its ufe in dying, ib. 437 
 
 1 '1 1 
 
 412 
 
 ib. 
 
 ib. 
 
 3*3 
 
 3 H 
 
 566 
 
 567 
 
 566 
 
 567 
 
 A L A N G A L root, larger, 
 
 ^ Smaller, 
 
 Its chemical hiftory, 
 
 Galbanum , its chemical hiftory, 
 
 Yields a blue oil, 
 
 Gall, animal, 
 
 Its nature and properties, 
 
 Its ofKcein the body. 
 
 Soluble in water and fpirit, 
 
 Renders refmous fubftances fojuble in 
 water, 568 
 
 Analyfed, ' ib. 
 
 Its ufes, ib. 
 
 Galls, excrefcences of the oak, 362 
 
 their chemical hiftory, ib. 
 
 Gamboge , its hiftory, 300 
 
 Its ufe as a colouring drug, ib. 
 
 Garlic, its chemical hiftory, 39 x 
 
 Peculiarities of its fmell, ib. 
 
 Its adlive principle an oil, 392 
 
 Garnet Jlone , melted into a hard black mats, 
 
 6 n. 
 
 Contains Iron, ib. 
 
 Gcllies of animal fubftances, 352 
 
 Differences from one another, 482 
 
 Are the matrix of the nutritious matter, 
 
 55 ° 
 
 and of that which forms volatile fait, 
 Contain the oil of the fubjedi, 532 
 
 Contain a large quantity of water, 524 
 
 Analyfed, 533 
 
 Gems, changes which they undergo from 
 
 fire, 6, n. 
 
 Made fufible, ib. 
 
 Conjecture about their formation, ib. 
 
 Imitations of, V. Glafs, 
 
 Gentian root, its chemical hiftory, 363 
 
 Diltin- 
 
 1 
 
I N D E 
 
 X. 
 
 Diftinguifhed from a poifonous root, 
 
 364, n. 
 
 A fuccedaneum to it, ib. 
 
 Ginger , brown and white, 411,4x2 
 
 their chemical hiftory ib. 
 
 Glades maria , 1 8 
 
 Gla/s, may be made from all mineral earths 
 by faline or metallic additions, 2 ,/eq. 
 and from vegetable allies, 479 
 
 not from the afhes of animal fubftances, 
 
 493 
 
 the lefs fait, the harder, 4, n. 
 
 imperfection of borax as a flux, 229, n. 
 differences in alcalies, 468, n. 
 
 made with lefs fait than ordinary, 9, n. 
 made without faline or metallic matter, 
 
 9, &c. 
 
 toughened by clay, 22 * n. 
 
 Malleable, whence the notion, 50, n. 
 Tranfparency promoted by manganefe, 
 
 80, n. 
 
 Coloured by metallic fubftances : 
 blue, by iron, 70, n. 
 
 by copper, 67 
 
 by cobalt, 150 
 
 green, by iron, 70, n. 
 
 by copper, 67, n. 
 
 red, by iron, 70, n. 
 
 by copper, 67, n. 
 
 by manganefe 80, n. 
 
 ruby coloured by manganefe, 38, n. 80,11. 
 
 by calx of Gold, 37, 
 
 yellow, by iron, 70, n. 
 
 by Silver, 51, n. 
 
 Made opake by calx of tin, 85, n. 
 
 by animal earths, 493 
 
 Metallic colours changed by long con- 
 tinuance of fire, 67, n. 70, n. 
 
 heightened or called forth by fmoky 
 flame, 38, n. 
 
 by nitre, ib. 
 
 by Sal ammoniac, ib. 
 
 Coloured without metallic matter : 
 green, 479 
 
 fine greenifh, of great luftre and hard- 
 nefs, 29, n. 
 
 greenilh like beryl, 26, n. 
 
 purple, 4, n. 
 
 yellow, 26, n. 
 
 topaz yellow, 29, n. 
 
 Gla/s, penetrated by fumes, 55, n. 
 
 Stained by metallic preparations, by igni- 
 tion without fufion, 51, n. 
 
 Varnifhed red by tin&ure of aloes, 307 
 
 Metals revived from, by fufion with phlo- 
 gifton, 55,11. 
 
 Earth recovered by fufion with alcali, and 
 folution in water, 4 
 
 Changed to a femivitreous flate like por- 
 celane, 479 
 
 Gla/s -gall, V. Sandiver 
 Glazing for earthen ware, black, 80, n. 
 blue, 149, n. 
 
 yellow, 51, 11. 
 
 Glue , how prepared 553, n. 
 
 Differences in its quality according to the 
 Subject 553 
 
 Changed into a vifcid mafs like birdlime, 
 
 125 
 
 Analyfed 
 
 Fifh-glue, V. Ichthyocolla 
 Glutinous matter not diffoluble in water or 
 fpirit 350 
 
 Gold, its charadters 32 
 
 Penetrated by water 254 
 
 Fixity in the fire, 33 
 
 Phaenomena in fufion, 32, n. 
 
 Habitude to other metals, 33 
 
 Changes of its properties by art 34 
 made brittle, ib. 
 
 made pale, 43 
 
 made white, 35, n- 
 
 made red, 43, n. 
 
 colour heightened, ib. 
 
 volatilized, 34 
 
 degraded by an antielixir, 34, n. 
 
 Whether its tinging matter feparable, 38 
 Diflolved in aquaregis, 33, 35, 
 
 in aqua fortis, 33, n. 
 
 in Spirit of Salt, ib. 208 
 
 by a preparation of vinegar, 1 1 9 
 
 by aether, 39 
 
 by effentia! oils, ib. 
 
 in fufion, by hepar Sulphuris, 35 
 
 r.ot by pure Sulphur, ib. 
 
 How made potable by Mofes, 35 
 
 Precipitation and redifl'olution by alcalies, 
 
 3 6 > n - 
 
 Fulminating precipitate, ib. 
 
 Does not fulminate without volatile alcali, 
 
 489, n. 
 
 Precipitation by inflammable Subftances, 
 
 39, n. 
 
 by metallic Subftances, 37 
 
 Cryftals, 34, n. 37 
 
 with aether, 455 
 
 Red ftain from its folutions, 33, n. 
 
 Ruby glafs from its precipitates, 37 
 4 H Methods 
 
I N D 
 
 Methods of diftinguifhing in liquors, 37, 
 
 39 > n - 
 
 Meta!* in imitation of it, 121 
 
 how diftinguifhed, 42, 43 
 
 Its medical hiftory, 39 
 
 Natmal hiftory, 39 
 
 Extraction from its matrices, 39, 40, n. 
 Contained in Sands, ib. 
 
 Methods of extracting, ib. 
 
 Standard gold, 41 
 
 Purification from Silver, 41, 42 
 
 from platina, 43 
 
 from imperfeCt metals, 4 C 43 
 
 from emery, 1 1 2 
 
 from all metallic Subftances, 37, n. 
 Purification by antimony, 129 
 
 whereon it depends, • ib. 
 
 Retains lead in cupellation, 41, n. 
 
 Its remarkable affinities with lead, copper 
 and filver, ib. 
 
 Recovered from Sweepings, £sV. by amal- 
 gamation, 95 
 
 Taken from gilt Silver, 219 
 
 Augmentation of it by the alchemifts, 44 
 Gold, white, V. Platina, 
 
 Grafting of trees, its ufe and effeCt, 261, 
 Graine d’ avignon , 433 
 
 green dye from it, ib. 
 
 Gram cnidia , chemical hiftory of, 344 
 Grand paradift , their chemical characters, 
 
 417 
 
 Granulation of metals, 55,62,117 
 
 Grapes , their differences from expofure to 
 Sun, &c. 441, 442 
 
 Gravity , Specific , infufficient for determining 
 the proportions of two bodies in a given 
 mixt, 66, n. 
 
 Dimimfhed by mixture, 45, n. 41, 11. 
 Tncreafed by mixture, 66, n. 430, n. 
 Of metallic mixts, feldom anfwers to the 
 mean gravity of the ingredients, ib. 
 
 ill 
 
 Of an ore, greater than of the metal it 
 contains, 89, n. 
 
 Difference in Summer and winter, 254 
 Green leaves , hiftory of their colouring mat- 
 ter, 434 
 
 Give out their colour to Spirit of wine, ib. 
 to dulcified acid Spirits, 454 
 
 and to oils, 434 
 
 not to water, ib. 
 
 in greateft perfection to Spirit after the 
 aCtion of water, 399 
 
 Give a yellow dye to woollen, 434 
 differences in the colour according to 
 fijhe fajts in the preparatory liquor, ib,. 
 
 E X. 
 
 Some faid to give a green dye, 434 
 Some yield by putrefaClion a blue fecu] a 
 
 435 
 
 Their green fuppofed to be compounded 
 of blue and yellow, ^8 
 
 Variations of the colour by different ad- 
 mixtures, ^24 
 
 Green lake by lime water, t b. 
 
 Green colour of dried berries, foluble in 
 water, 433 
 
 foluble in fpirit, not in water, 4,16 
 
 Of feeds, extracted by fpirit, not by 
 water, 397 
 
 G, rJ Dyc ’ +37. 43 + 
 
 f akes, f k «„ 431.433.434 
 
 Stain for bones, 6 7 n 
 
 Glafs, See Glafs. 
 
 Guqiacum gum , its chemical hiftory, 298 
 
 wood, o 40 
 
 bark, 3^ 
 
 Gums , their characters, 264 
 
 exueding from vegetables fpontane- 
 
 266 
 
 extracted by art, 2 6^ 
 
 how obtained pure from refin, 268 
 Agreement and difagreement of different 
 
 g ums > 282, and n. 
 
 Their ufes, ^ 
 
 Render oils and refins mifcible with 
 water, 283 
 
 Are the medium by which oily and refi- 
 nous juices of vegetables are ex- 
 tracted by water, ib. ibj. 
 
 Chemical hiftory ot gummy vegetables, 
 
 335 
 
 Gummy-refms , their characters, 265, 300 
 Hiftory of concrete gummy-refins, ib. 
 of gummy-refinous vegetables, 355 
 Gun ponder, its difcovery, j - Q 
 
 its compofition, 
 
 Gypfeous earths, their characters, 18 
 
 melt with clay, 22, n> 
 
 bake femitranfparent with fritt, 18, n. 
 promote the fufion of forged iron, 78. n. 
 in contact with burning fuel, emit ful- 
 phureous vapours, become luminous 
 in the dark, burn into lime, 19, m 
 compofed of calcareous earth and vi- 
 triolic acid, ib , 
 
 artificial production of, ib. 8, 
 
 Gypfu?n, its qualities and ufes, ig^ n= 
 
 difference in quality according to de- 
 gree of calcination,. ib. 
 
 made more durable in the air, ib. 67 
 tinged of different colours, iq, n 
 
 HeEMJTJTEi 
 
I 
 
 N D E X. 
 
 H 
 
 T T/E M AT IT E S, an iron ore, 80, n. 
 Its characters, ib. 
 
 Hair , ftained black, 47, n. 58, n. 108 
 Depilatories, 155, 158 
 
 Prevented from growing, 158 
 
 Analyfed, 548 
 
 Hartjhorn , analyfis, 520 
 
 Preparations of, 521 
 
 Hatching of eggs by artificial heat, 557, n. 
 
 unheeded caufe of failure, ib. 
 
 Heat , produced from cold liquors, 1 61 
 See Eire, 
 
 does not always expand bodies, 69, n„ 
 Hedercc-gum , uncertainty of its origin, 311 
 chemical hiftory, ib. 
 
 Heliotropium tricoccum , 433 
 
 turnfol how prepared from, ib. 
 
 Hellebore , black, 348 
 
 White, 347 
 
 Their chemical hiftory ib. 
 
 Hepar fulphur is, 1 6 7 
 
 Gives a golden tinCture to fpirit of wine, ib. 
 The fulphur imbibed from it by certain 
 oils, 169 
 
 Unites with moft metals in fufion, and 
 renders them foluble in water, ib. 
 HermodaStyl root, its chemical hiftory, 354 
 Remarkable differences from applying 
 water or fpirit firft, ib. 
 
 Hickery tree, preparation of fugar from, 327 
 Hippopotamus tooth, chemical hiftory of, 
 
 522 
 
 Honey, collected from vegetables, 330 
 
 Whether different in different flowers, ib. 
 Chemical hiftory and ufes, 341 
 
 Agreement with other vegetable fweets, ib. 
 Made to affume a folid cryftalline form, 
 
 34 1 5 n. 
 
 Soluble in water and fpirit, 341 
 
 Produce of fpirit by fermentation, 242 
 Hoofs , of animals, their characters, 511 
 Elks analyfed, 5 14 
 
 Cows analyfed, 515 
 
 Hops, their ufe in malt-liquors, 449 
 
 Hop/lalks , cloth made from, 429 
 
 Horehound leaves, their hiftory, 366 
 
 Hornet infeCt, contains acid, 498 
 
 Horns , their characters, 5x1 
 
 Differences from bones, 511, 516 
 
 How figured and joined, 513, n * 
 
 Cows, analyfed, 5x2 
 
 Harts , analyfed, 5 20 
 
 Rhinoceros’ s, analyfed, 51 1 
 
 Horfe-radijh, its analyfis, jgo 
 
 its activity in an eflential oil, ib. 
 
 Hot-beds , ? renewals of air how procured 
 
 Hot-houfes, 5 in them, 262,263 
 
 Huile de pumicin, 324 
 
 de Senegal , ib. 
 
 Hyacinth Jlone, contains iron, 6, n. 
 
 melted per fe into hard black mafs, ib. 
 Hypericum, its hiftory, 371 
 
 HyJJop , its hiftory, 421 
 
 I. 
 
 J ALAP, its hiftory, 352 
 
 worm-eaten, what ufes fit for, 353 
 Promotes fermentation, ib. 
 
 Japan- earth , infpiflated juice, 317 
 
 its chemical hiftory, ib. 3x8 
 
 fafper, ftained black, 47, n. 
 
 Ice, 255 
 
 Excites heat with the vitriolic acid, 16 r 
 cold with the marine, 196, n. 
 
 greater cold with the nitrous, ib. 
 
 lefs cold with nitre in fubftance than 
 with fea-falt. 
 
 Ichthyocolla , account of its preparation, 553 
 Chemical hiftory, ib. 
 
 Analyfis and ufes, 554 
 
 Whether wines fined by it wholefome, ib. 
 
 Z et ’ . , 245 
 
 Jews pitch , 242 
 
 Ignatius’s bean , 346 
 
 Ignis frigidus, 20 
 
 Imperatoria root, chemical hiftory, 392, 393 
 Indian-wheat, fugar from the ftalks, 328, n. 
 Indigo , account of its preparation, 435 
 Different forts, 436 
 
 Diflolved by fixed alcali into a green li- 
 quor, ib. 
 
 Diflolved by vitriolic acid into a blue li- 
 quor, which in a boiling heat be- 
 comes green, 436, 437 
 
 Its habitude to other menftrua, ib. 
 
 How employed for dying blue, 436 
 for dying faxon blue and green, 437 
 for printing linen, 436 
 
 for ftaining leather, ib. 
 
 Inflammable principle : 
 
 Different from fulphur, 165 
 
 Enters the compofition of metals, 53 
 The fame in one body as in another, ib. 
 T ransferred from one body into another, ib. 
 Abforbed from one metal by another, 
 
 55 ’ n - 
 
 How diftinguifhed in bodies, 200 
 
 Infufums , general obfervations on, 267 
 4 H 2 Differ- 
 
INDEX. 
 
 Difference in the aftion of cold and hot 
 water, 267 
 
 Ink, Black writing , 1 8 1 
 
 improved, 385 
 
 ftain difcharged from linen, 423 
 
 Indian, whence prepared, 539 
 
 Printers, 290, n. 
 
 Sympathetic, made legible by palling a li- 
 quid over the invifible writing, 155 
 by the volatile vapour of a liquor, 168 
 by warmth, difappearing again in the 
 cold, 1 14, 152 
 
 Infefls, the various places of their production, 
 
 494 
 
 Their transformations, 503 
 
 Chemical hiftory of feveral, 494 ,/eq. 
 How cured and preferved from decay, 
 
 495 ) n - 
 
 Ipecacuanha., its hiftory, 35 7 
 
 Iris, common, 371 
 
 Florence, ib . 
 
 its chemical hiftory, ib. 
 
 Iron, its general characters, 68 
 
 Ignited by mechanic impulfe, ib. 
 
 Phaenomena in the fire, ib. 
 
 Obfervations on its property of welding, 
 
 69, n. 
 
 Fufion remarkably promoted by impulfe 
 of air, 76, 11. 
 
 Shrinks in fufion, and expands again in 
 
 fixing, 69, m 
 
 Preferved from ruft, 70 
 
 Its habitude to other metals, 69, n. 
 
 Malleable with regulus of cobalt, 1 52, n. 
 Attracted by magnet when mixed with 
 confiderable proportions of other 
 metals, 83 
 
 except regulus of antimony, ib. 
 
 Not mifcible with lead, or mercury, 69,11. 
 Some metals abforbed by it from melted 
 lead, ^ 57, n. 
 
 others abforbed from it by melted lead, 
 
 ib. 
 
 Vitrefied by a burning glafs, 70 
 
 Calces promote the vitrification of fotne 
 earths, 23, n. 
 
 prevent the vitrification of others, 56. n. 
 eafy of reduClion, 83, n. 
 
 colours they impart to glafs, 69 
 
 Its folubility in different liquors, 70 
 Phaenomena with different acids, 70, 71 
 Diffolved in alcalies, 71, 73, n. 
 
 Precipitated from fixed alcali by volatile, 
 
 73 ) n « 
 
 Volatilized, 71 
 
 Covered with a cupreous coat by folution 
 of copper, 177 
 
 with a golden one by folution of gold, 
 
 7 1 
 
 Diffolved in acids, ftrikes a black with 
 vegetable aftringents, 72 
 
 a deep blue with animal phlogifton, 
 
 72,11. 
 
 Ufes in ftaining, dying, &c. ib. 181 
 Made fufible by fulphur, 73 
 
 Heat and flame produced from a mixture 
 of it with fulphur, 74 
 
 retains the acid of the fulphur, 173 
 Its medical hiftory, 74 
 
 Contained in waters, 175 
 
 how dilcovered, 72, n. 
 
 In coloured earths and ftones, 76 
 
 In animal and vegetable fubftances, ib. 
 Its ores, 74, 75 
 
 Method of fmelting from the ore, 75 
 Smelted with foflil fuel, 75, n. 
 
 fufion promoted by calcareous earths, 
 
 18, n. 
 
 Differences in its quality from different 
 ores, 76. 
 
 Its goodnefs how judged of, 77 
 
 Cajl, Its different kinds and qualities, 76 
 Purified by fufion, ib. 
 
 Softened, fo as to be filed, &c. by ce- 
 mentation, 77, m. 
 
 more perfectly by forging, ib. 
 
 Manner of forging, 76, n. 
 
 Lofes its, fufibility by being made mal- 
 leable, 68, 77, m 
 
 Malleable melted iron, 78, n. 
 
 Forged, its quality diftinguiftied by texture, 
 
 77 ) n - 
 
 Cold-fhare and red-fhare, what and 
 whence, 78, n. 
 
 Heavier than the caft, ib. 
 
 Made fufible by gypfum, ib. 
 
 Changed into fteel, V. Steel. 
 Cafe-hardened, 79, n. 
 
 Iron-mould, difcharged from linen, 423 
 Juices of falirte plants contain their virtue, 
 
 280 
 
 of odoriferous herbs and flowers not, ib. 
 Ivory , its hiftory and analyfis, 524 
 
 ftained. See Bones. 
 
 Ivory-black, 525-: 
 
 ■white. . ib » 
 
 MALL 
 
N D E - X. 
 
 K. 
 
 jrAL I, its fixt fait diflerent from that 
 of other vegetables, 468, n. 
 
 fimilar to the mineral alcali, ib. 
 
 yields a blue fecula, ib . 
 
 Kaolin , an ingredient in china ware, what, 
 
 t8, n. 
 
 Kermcs , its hiftory as a colouring drug, 508 
 Its advantages in dying, ib. 
 
 Dying of different colours with it, ib. 509 
 Kermes mineral , 133 
 
 Kernels of fruits, which have bitternefs or 
 flavour, contain a poifonous principle, 389 
 
 L. 
 
 T AC Sulphuris , 1 67 
 
 changed into yellow fulphur, 167, n. 
 Lacca, what and how obtained, 333 
 
 Its chemical analogy with wax, 334 
 
 Its colour owing to infeCts, 333 
 
 Its habitude to various menftrua, ib. 
 Whether ufeful in varnifhes, ib. 
 
 Its colouring matter l’eparated in form of 
 lake, 333, n. 
 
 Method of dying fcarlet with it, ib. 
 Lacmus , 438 
 
 Ladanum, refin, different methods of collect- 
 ing, _ 295 
 
 Its qualities and analyfis, 295, 296 
 
 Labes, how prepared, 266, n. 435 
 
 Blue, from anil leaves, 435 
 
 from woad leaves, 437 
 
 probably procurable from leavesof other 
 plants, 438 
 
 Crimfon from Brazil wood, 386 
 
 from cochineal, 505, 507 
 
 Green, from blue flowers, 431 
 
 from green leaves, 434 
 
 from Buckthorn berries, 433 
 
 Purple from Buckthorn berries, ib. 
 
 Red, from fafflower, 432 
 
 from gum lac, 333, n. 
 
 from red woods, &c. 386 
 
 Yellow from Buckthorn-berries, 433 
 from fuftick and other yellow drugs. 
 Lamp-black, how prepared, 289 
 
 Lapis atramentarius, 18 1 
 
 Bononienfis , 1 9 
 
 Carpionum, Per car urn , 525 
 
 Hematites, 80, n. 
 
 Lazuli, 
 
 Lucidus, 20 
 
 Manat i, 527 
 
 Nephritkus 5 26 
 
 Qllaris, 26, n. 
 
 Specular is , .* 8 
 
 Lard, analyfed, 559 
 
 Lavender, French , its chemical hiftory, 42 i 
 Lead, its general characters, 54 
 
 Method of carting into large ftieets, 54, n. 
 Mechanic differences of cart; and milled, 
 
 c zb* 
 
 How granulated, 55 
 
 Made fonorous, 54, n. 
 
 Converted into diflerent forms by fire, 
 
 55 ’ 56 
 
 Emits. fumes ill the fire, 54 
 
 Increafes in weight, 56 
 
 Calces, their eafy revival, 55 
 
 abforb phlogifton from iron, 55, n 
 vitrification of, 56 
 
 ufe as an ingredient in glafs, 56, n. 4 
 inconvenience as a bafis for artificial, 
 gems, 56, n. 
 
 Habitude to other metallic bodies, 57, n. 
 
 not mifcible with iron, ib. 
 
 abfor.bs copper and filver in fufion from 
 iron, ib. 
 
 eliquated from copper, ib. 
 
 imbibes filver from copper, ib. 
 
 not gold, ib. 
 
 retained by gold in cupellation, 41, n„ 
 not by filver, 57, n. 
 
 Ufe in purifying gold and filver, 56 
 
 Suppofed convertible into filver, 57 
 Calcination with tin, ib. 
 
 Hyacinth -glafs with arfenic, 57 
 
 Made refractory by fulphur, ib. 
 
 Difl'olved in aqua fords, 58 
 
 in aqua regis, 58, n. 
 
 in fpirit of fait, ib. 
 
 in vegetable acids, 59 
 
 in oils, 58, n. 
 
 in alcaline liquors, ib.. 
 
 Corroded by the vitriolic acid, ib. 
 Extricates a cauftic volatile fpirit from 
 fal ammoniac, 22 
 
 Difl'olved freely, by human heat, in 
 menftruum inoffenfive to the body, 
 
 93 ’ n - 
 
 Its medical hiftory, 59 
 
 Method of diftinguifhing oils and wines 
 fophifticated with it, 155 
 
 Its ores, 60 
 
 Extradion from the ore, 60, n, 
 
 Contains copper, 60,61 
 
 Contains filver, 6r, n. 
 
 Purification from copper, 57, n-». 
 
 from all metallic bodies, 61, n. 
 
 Leather * 
 
 PI 
 
N D E X. 
 
 Leather , how prepared, 549 
 
 Preparation of glue from it, 553, n. 
 Its glue ftronger than that of folid animal 
 matters, ib. 
 
 Analyfed, 55O 
 
 Stained black, 47, 72 
 
 blue, 436 
 
 purple, 33 
 
 red, 333 
 
 Leaves , of different plants have their active 
 principles perfected at different pe- 
 riods of their growth, 264 
 
 Give out their green colour to fpirit and 
 oils, 434 
 
 not to water, ib. 
 
 Variations of their colour by different 
 mixtures, ib. 
 
 Their ufes as colouring drugs, ib. 
 
 Their herbaceous matter deftroyed, and 
 the filaments left in the original form 
 of the leaf, 428 
 
 Lemons , effential oil of the peel, 408 
 
 Cryftalline acid fait from their juice, 423 
 Lentifk-tree , 297 
 
 Leopards-bane , its hiftory 37O 
 
 Ary, method of determining the ftrength of, 
 
 467 
 
 Light , folar , its influence in vegetation, 
 
 261, n. 
 
 Its different effe£t on colours from that of 
 culinary fire 48, n. 510 
 
 Lignum aloes , 419 
 
 Nephriticum , 385 
 
 Rhodium , 417 
 
 Lime Jl ones, their different kinds, 14 
 
 Contain fulphur and marine acid, ib. 
 Diftinguifhed by diffolving in aqua fortis,8 
 See Calcareous. 
 
 Linen , its differences from woollen and filk 
 in fufceptibility of colours, 429 
 in corrofibility by certain liquors, 540 
 Bleached, See Bleaching. 
 
 Cleared from iron moulds and fpots of 
 ink, 423 
 
 Printed blue, 436 
 
 red, with madder. 
 
 yellow, 72 
 
 Stained purple, 510 
 
 Liquefaction, of folid bodies by mixture, 220 
 Liquid-amber, 2:91, n. 292, n. 
 
 Liquorice, its chemical hiftory, 425 
 
 Adulterations of its extradl, ib. 
 
 Analyfis of different extracts, ib. 
 
 Sweet matter of the extract feparated by 
 fpirit, ib. 
 
 I 
 
 Lithantrax , 244 
 
 Litharge, how made, 56 
 
 differences in colour, whence, 56, n. 
 
 purified, ib. 
 
 Litmafe , 438 
 
 Loadjlone, its natural hiftory, 82 
 
 Its attra£five power, 83 
 
 repulfive power, 84 
 
 directive pov/er, ib. 
 
 communicative power, ib. 
 
 attracts iron mixed with other metals, 83 
 a£ts not on calces of iron, ib. 
 
 a£fs not on feveral iron ores till roafted, 
 
 83, n. 
 
 Its power weakened and deftroyed, 84 
 Examined by fire and menftrua, ib. 
 Loams, 23, n. 
 
 Windfor , its qualities, ib. 
 
 melted, ib. 
 
 Logwood, chemical hiftory of its colouring 
 matter, 385 
 
 Its ufes in dying and ftaining, ib. 
 
 Luna, V. Silver. 
 
 Luna cornea, its preparation, 49, n. 
 
 Its fufibility and volatility, ib. 
 
 Soluble in volatile alcalies, ib. 
 
 Made of a glaffy appearance and malle- 
 able, 50, n. 
 
 Silver recovered from it without Jofs, 
 
 r 49 > n. 
 
 Lunar caujlic , 47 
 
 Lungwort, chemical hiftory of, 380 
 
 Lycopodium, its chemical hiftory, 427 
 
 M. 
 
 JlyfACE , its chemical hiftory, 405 
 ■LyL Madder, hiftory of, 387 
 
 Bones of animals tinged by taking it in 
 food, ib. 
 
 Chemical hiftory of its colouring matter, 
 
 3 8 7 
 
 Red dye from it, ib. 
 
 Does not form a purple with blue, 388 
 Purple and crimfon dyes from it, ib. 
 Magijlery of Antimony, 137 
 
 Of Bifmuth, 107 
 
 ftains hair black, ib. 
 
 its inconvenience as a fucus, ib. 
 
 Magnes arfenicalis, 147 
 
 Magnefia alba, from mother-ley of nitre, 204 
 from bitter purging fait, 190 
 
 from vegetables by incineration, 478 
 Diftinguifhed from other earths, 205, 
 
 190, n. 
 
 Maonet, fee Loadftone. 
 
 Malt 
 
I N D E X. 
 
 Malt, its preparation, 
 
 448 
 
 Malt liquors , 
 
 ib. 
 
 Differences of ferments, 
 
 ib. 
 
 of waters. 
 
 ib. 
 
 of their fermentability, 
 
 449 
 
 of the ufe of additions, 
 
 ib. 
 
 Analyfis of different forts, 
 
 ib. 
 
 Aianati lapis, analyfed, 
 
 ■ S 2 7 
 
 ManganeJ'e , not an iron ore, 80, n. 
 
 Various experiments on, ib. 81, n. 
 
 Tinges glafs of a ruby colour, 38, n. 
 Its ufe in making glafs tranfparent, 80, n. 
 in black glazing, 
 
 ib. 
 
 Manna , exuding from different trees, 324 
 
 328 
 
 3 2 5 
 ib. 
 
 326 
 ib. 
 ib. 
 99 
 
 Extracted from birch, 
 
 Common , whence, 
 
 Different kinds and fophiftications. 
 Purification, 
 
 Analytical experimenfs on. 
 
 Fermented into a vinous liquor, 
 
 Manna metallorum, 
 
 Maple tree, preparation of fugar from it, 
 
 3 2 7 > n - 
 
 Marble , ffained black, 47, n. 
 
 green, 66, n. 
 
 red, 299, n. 386, n. 
 
 violet, 33, n. 386, n. 439 
 
 yellow, 300? n. 384 
 
 Colours how prevented from fpreading, 
 
 439 
 
 Refinous colours, how applied, 299, n. 
 
 300, n. 
 1 10 
 ib. 
 560 
 ib* 
 
 335 
 
 219 
 
 Marcafita argent ea , 
 
 Aurea, 
 
 Marrow, analyfed. 
 
 Differences from fats, 
 
 Marjhmallow , chemical hiftory of, 
 
 Martial flowers , of Sal ammoniac, 
 
 Marygold flowers , wild yield a yellow dye, 
 
 43 1 
 
 Garden, of different quality, 432 
 
 Maflerwort root, its chemical hiftory, 392 
 Maflich re fin, 297 
 
 Its chemical hiftory and ufes, 298 
 
 Maflicot , ’ 55 
 
 Materia per lata, 1 37 
 
 Matricaria leaves, chemical hiftory of, 421 
 Mattalifla root, its chemical hiftory, 353 
 Matter , its converfton into new forms, 260, 
 
 " 481, See. 
 
 Meelbatz, 26, n. 
 
 Melafles, 329 
 
 Mercurius dulcis, 99 
 
 vita,. _ 134 
 
 Mercury, its general properties, 91 
 
 Its habitude to metals, 93 
 
 diffolves, by triture and heat, all but 
 iron, nickel, and arfenic, 93, n. 
 made to adhere to iron, 69, n. 
 
 made to difi'olve lead in gentle warmth, 
 
 93’ n. 
 
 diffolves calces of fome metals precipi- 
 tated by other metals, 103 
 
 not thofe precipitated by alcalies, ib. 
 nor calces made by fire, 93, n. 
 
 nor fulphurated metals, ib. 
 
 imbibes fome metals from their folu- 
 tions in acids diluted, 93, n. 
 
 and from their folutions in alcalies, 
 
 489, n. 
 
 carries fome metals through leather 
 with it, 93, n. 
 
 elevates metals in diftillation, 93, n. 
 
 94 ’ n * 
 
 Its indeftrudtibility, 92, 97 
 
 fallacy of proceffes for converting it 
 into water, 93, n. 
 
 fallacy of proceffes for coagulating and 
 fixing it, 103 
 
 Transformed into red and black powders, 
 
 91, n. 
 
 recovered without addition, 92 
 
 Congealable in fome degree by cold, 
 
 91, n. 
 
 Made to diftil by heat of human body, 
 
 a • • 93> n - 
 
 Animated or philofophic, 94, n. 
 
 Strongly retained by filver and vitriolic 
 a Dd, 50, n. 
 
 Fixed by gold, 92 
 
 Diffolved by nitrous acid, 97 
 
 by vitriolic acid, 97, n. 102 
 
 by marine acid, 98 
 
 by vinegar, 98, m 
 
 by fixt alcali, 9,7, n. 
 
 by water, - 98, n . 
 
 Medical hiftory, 95, 96 
 
 its fumes, perfedl mercury, unchanged, 
 
 . . 9D 95 
 
 various compohtions, 96 
 
 Chemical preparations, ib. feq. 
 
 Calx or precipitate per fe, 102 
 
 Cinnabar, factitious, 100 
 
 of antimony, ib. 
 
 Sublimate corrofive, 98 
 
 not adulterable with arfenic, 99, 142 
 Precipitates, 10 1 
 
 Turpeth mineral, 97, ioz 
 
 diffolved in water, 97 
 
 Its ores or mineral forms, 104 
 
 Ac- 
 
INDEX. 
 
 Account of its mines, 104 
 
 Extraction from the ores, zb. 
 
 Its purity how judged, 94 
 
 Methods of purifying, 95, 975 n- 
 
 How to be kept, 94 
 
 Its mechanic ufes, 95 
 
 .Metallic bodies : 
 
 Characters of metals, 31 
 
 and femimetals, zb. 
 
 Perfect, 32 
 
 and imperfect, 53 
 
 All contain an inflammable principle, 53 
 their phlogifton the fame with that of 
 vegetables and animals, zb. 
 
 conjecture about their other principles, 
 
 54 
 
 Mercury not an ingredient in them, 
 
 104 
 
 fallacy of a procefs by which mercury 
 is laid to have been extracted from 
 lead, 58, n. 
 
 Imperfect, deflagrate with nitre, 53 
 fome flame by themfelves, 85, 115 
 
 Converted by fire, in open veffels, into 
 calces, 53, &c. 
 
 emit fumes in calcination, 107, n. 
 
 yet increafe in weight, 106, & c. 
 
 Calces revived by phlogifton, 53, &c. 
 
 greater heat required for revival of calx 
 than for the fufion of the metal it- 
 felf, 1x7, xi. 
 
 except iron, 83, n. 
 
 a part unrevivable, 54 
 
 capable of being made totally irredu- 
 cible, . 54 
 
 Phlogifton extracted by folution in acids, 
 
 53 > &c. 
 
 inflammable vapour in fome diflolu- 
 tions, 70, 1 17 
 
 precipitates by alcali not revivable 
 without phlogifton, 53 
 
 phofphorus from fome metals and phof- 
 phorine acid, 576 
 
 Phlogifton imbibed from fome metals by 
 calces of others* 55, n. 
 
 Mixed with one another, form com- 
 pounds whole qualities are not the 
 mean of thofe of the ingredients : 
 new colour from their mixture, 120, 
 
 121 
 
 fufibility greater than of either ingre- 
 dient, hi 
 
 fpecific gravity greater, 66 
 
 diminution of fpecific gravity, 41, n. 
 increafe of calcinability, 57 
 
 increafe of fonoroufnefs, &c. 66, &c. 
 
 Thofe which are brittle when heated, 
 communicate the fame quality to thofe 
 which are not, 66, n. 
 
 Some not mifcible with others : 
 
 Iron with Lead, 57, n. 
 
 Silver with Nickel, 153 
 
 Bilmuth with Regulus of Cobalt, 152 
 Zinc with Nickel, 153 
 
 Mercury with Iron, 69, n. 
 
 Mercury with Arfenic, 93, n. 
 
 Mercury with Nickel, 153 
 
 Separations of metals from one another 
 by adding a metal repugnant to one of 
 
 the ingredients of the mixt, 57, n. 
 
 None mifcible, in their metallic ftate, 
 with vitreous fubftances. 
 
 All calces mifcible with vitreous fub- 
 ftances. 
 
 Sulphur the only unmetallic body that 
 mingles in fufion with metals, 
 gold, platina and zinc repugnant to 
 pure fulphur, 169, n. 
 
 All but zinc mifcible with fulphurated 
 alcali, ib. 
 
 made foluble by it in water, ib. &c. 
 All volatilized by marine acid, 34, 208 
 Volatile made more fixt by vitriolic acid, 
 
 102 
 
 Metals compound, in imitation of gold, i2r 
 In imitation of filver, 145 
 
 In imitation of fteel, ib. 
 
 Bell metal, 66 
 
 Brafs, 65 
 
 Bronze, 121 
 
 For Mirrors, 120, n. 
 
 For Organ pipes, 57, n. 
 
 Pewter, 89 
 
 For Printers types, 111 
 
 For Soldering, ib. 
 
 Spelter folder, 122 
 
 Meteors, fiery, whether owing to fulphur, 172 
 Metheglirz, 331 
 
 Microcofmic Salt, fee Salt Microcofmic. 
 
 Milfoil , its chemical hiftory, 409 
 
 yields a blue oil, ib. 
 
 Milk, its nature and differences. 569, 570 
 Affecfted by the food. ib. 
 
 By what fubftances diluted or coagulated, 
 
 ■ 574 > li- 
 lts coagula rediflolved. zb, 
 
 Preferved from coagulation, ib. 
 
 Made equally thick. 573 
 
 Analyfesof that of different animals. 570 
 Saccharine concrete obtained from it. 572 
 
 Rancid, 
 
I 
 
 N D E X. 
 
 Rancid, fweetened. 569, n. 
 
 Millepedes, chemical hiftory of, 502 
 
 Minerals , earthy, I 
 
 Metallic, 31 
 
 Saline, 159 
 
 Bituminous, 230 
 
 See the refpeCtive heads. 
 
 Mines , external marks of, 104 
 
 Damps in them, artificial imitations of, 
 
 70, 117 
 
 111 effeCis of mercurial ores on the mi- 
 ners, 96 
 
 how remedied, ib. 
 
 Minium , how made, 55, 56, n. 
 
 Its increafe, ib. 
 
 Lofs of weight on revival, ib. 
 
 Mirrours , compound metal for, 120, n. 
 
 Mjspickel , 149 
 
 Monks rhubarb , its chemical hiftory, 361 
 Morter , 14, n. 
 
 MoJJcs , elegant colours obtained from, 438, 
 
 439 
 
 Mother-ley , what, 204 
 
 Mother-of-pearl , its chemical hiftory, 541 
 Mould , vegetable, 478 
 
 animal, 494 
 
 Mucilage , 264 
 
 Mullein flowers, chemical hiftory of, 426 
 their fweetnefs extracted, ib. 
 
 Mummy, chemical examination of, 551, 552 
 Mufcle Jhells , analyfed, 540 
 
 yield a ftrong lime, ib. 
 
 Mujk , its hiftory and fophiftications. 563 
 Belt way of preferving. ib. 
 
 Great adhefivenefs of its fmell. 564 
 Gives over its fmell in diftillation with 
 water. ib. 
 
 not with fpirit. ib. 
 
 How ufed in perfumes. ib. 564, n. 
 
 MuJd, its differences from different manage- 
 ments, 442 
 
 enriched, ib. 
 
 preferved, without fermentation, by 
 boiling, 441, 442 
 
 by fume of Sulphur, 445 
 
 Myrrh, its chemical hiftory, 316 
 
 N 
 
 fsT-A PHT HA, 230 
 
 * Nardus Indica, its chemical hiftory, 420 
 Natron, 197 
 
 Nephritic Jlone, 26 
 
 Experiments on, 27 
 
 Its colour from Copper, 26, n. 
 
 A fpecies of fteatites, ib. 
 
 Nephritic wood, 3 g y 
 
 chemical differences from other woods, 
 
 ib. 
 
 lingular changes of colour in its infufion, 
 
 ib , 
 
 Nettle ftalks, cloth made from, 429 
 
 Neutral Salts, their characters, 159 
 
 Diftinguilhed from compound falts by alca- 
 lies making no precipitation in folu- 
 tions of them, 190, n. 
 
 Compofed of alcali and acid, 159 
 
 Vitriolic acid forms, with 
 
 vegetable alcali, Vitriolaied tartar, 190 
 mineral alcali, Glaubers Salt, 193 
 
 volatile alcali. Secret Sal ammoniac, 194 
 
 Nitrous acid forms, with 
 
 vegetable alcali, Nitre 197 
 
 mineral alcali, Cubic Nitre, ib. 
 
 volatile alcali, Ammoniacal Nitre , ib. 
 
 Marine acid forms, with 
 
 vegetable alcali, Regenet . Sea Sale, 215 
 mineral alcali, Sea Salt, 209 
 
 volatile alcali, Sal ammoniac, 216 
 
 Acetous acid forms, with 
 
 vegetable alcali, Sal diureticus , 461 
 
 mineral alcali, 468 
 
 volatile alcali, an uncryftaliizable fluid, 
 
 460 
 
 Tartar forms, with 
 
 vegetable alcali. Soluble Tartar, 457 
 
 mineral alcali, Seignettes Salt. 
 
 Nigella feeds, chemical hiftory of, 406 
 
 Nihil, Nihil album, 127 
 
 Nitre, never found native, 197 
 
 exifts not in waters or in the air, 198 
 
 where generated, 199 
 
 produced by putrefaction, 198 
 
 ferments for its production, ib. 
 
 Its imperfeCt ftate, 199 
 
 Extracted and made perfeCt, ib. 
 
 Purification, 200 
 
 Marks of its purity, ib. 
 
 Its characters, 200 
 
 melts thin as water, ib. 
 
 deflagrates with all inflammable fub- 
 
 ftances in a red heat, ib. 
 
 its acid deftroyed by deflagration, 20 r 
 a powerful flux for cryftalline earths, 
 
 9, n. 
 
 does not vitrefy calcareous earths, ib. 
 
 nor argillaceous ones, 22, n. 
 
 heightens the colour of Gold, 43, n. 
 
 heightens the colour of glafTes tinged by 
 fome metals, 38, n. 
 
 makes flefh red, 201 
 
 4 I preferves 
 
INDEX. 
 
 preferves animal fluids from coagulation, 
 enables inflammable fubftances to bum 
 without air, ib. 166, n. 
 
 Its chemical and mechanic ufes, 201 
 Commodious method of reducing it into 
 powder, ib. 
 
 Medicinal preparations, ib. 
 
 Fixt or alcalized nitre, by deflagration 
 with charcoal, 203 
 
 with tartar ib. 
 
 with metallic fubftances, 73, n. 139, 
 
 &c. 
 
 Spirit, different methods of preparing, 
 
 205 
 
 by vitriolic additions, ib. 
 
 by vitrelcible earths, 207 
 
 volatile and blue, by arfenic, 142, 207 
 Quantity of alcali it faturates, 195 
 
 Quantity of pure acid it contains, ib. 
 See acid, nitrous, 
 
 Nitrous Salt in vegetables, accidental from 
 the foil, 201, 262 
 
 Nilrum antimoniatum, 1 37, 2C2 
 
 cacheSlicum , 20 1 
 
 caujlicum , 1 39? 204 
 
 chalybeatum , 20 1 
 
 tubicum , 197 
 
 effentificatum, 20 1 
 
 fixurriy 203 
 
 fammans, 197 
 
 iufuccatum, 201 
 
 nitratum , ib. 
 
 regeneratum, 202 
 
 fulphuratum , 193 
 
 tabulation , 202 
 
 vitriolatum, 193 
 
 Nutmegs , 203 
 
 Activity confined to the coloured veins, 
 
 thefe not apt to be worm-eaten, ib. 
 
 Chemical hiftory, 404 
 
 their febaceous matter, ib. 
 
 Expreffed Oily its chemical hiftory, ib. 
 
 eflential oil extradted from it, 404 
 
 Nux vomica y its chemical hiftory, 346 
 
 o 
 
 /~\AK bark, its ufe in tanning, 549, n * 
 ^ Subftitutes to, 55 °? n. 
 
 Ochres, are ores of iron, 80, n. 
 
 worked as fuch, ib. 
 
 Odoriferous balfams, 404 
 
 Waters and fpirits, 564 
 
 Oils, 323 
 
 Odours , fee Smells . 
 
 Ofenbruch , 1 23 
 
 Off a alba, 224. 
 
 Oils , made mifcible with water, 283 
 
 Tinged of a fine red, 337, n . 
 
 Extra# the green colour of plants, 434 
 May be impregnated with all vegetable 
 colours except blue. 
 
 Oils, animal: 
 
 Expreffed from yolk of eggs. 556 
 
 from ants, 499? n. 
 
 fimilar in quality to the exprefled oils 
 of vegetables, ib. 
 
 Eflential, from Ants, 498 
 
 from odoriferous animal fubftances, 
 
 48.2 
 
 Empyreumatic, different from thofe of 
 vegetables, 493 
 
 and from one another, 492 
 
 Redtified, ib. 
 
 Their medicinal adtivity, ib. 
 
 Oih , mineral , native, 230 
 
 Extradted from bitumens, 235, &c. 
 Different from vegetable oils, 283, n. 
 Changed by acids into a bituminous con- 
 crete, ib. 
 
 Oils , Vegetable, 265 
 
 Expreffed or expreflible, ib. 
 
 method of extra&ing, 277 
 
 ufe and inconvenience of heat in the pro- 
 cefs, 278 
 
 Bring forth with them the flavour of aro- 
 matic fubjedis, 404 
 
 not any other principles, 278 
 
 Differences from one another, ib. 
 
 Lefs inflammable than eflential oils, ib. 
 Made foluble in fpirit of wine, 58, n. 
 
 478, n. 
 
 Made thick and dark coloured by boiling, 
 
 70, n» 
 
 Thickened without acquiring any colour, 
 
 ib. 
 
 Their drying, in paints, promoted, 184 
 Impregnated with lead, how difcovered, 
 
 59 
 
 Made into foap with alcalies, 476 
 
 Effential, 265 
 
 Principle on which their activity depends, 
 
 ib. 
 
 exhales from the oil in the air, 265 
 is imbibed by water, ib. 
 
 is commonly lefs volatile than fpirit of 
 wine, 277 
 
 Their analogy to refins, 269 
 
 changed into refins, ib. 
 
 Are the matrix of fmell of odoriferous 
 vegetables, 265 
 
 Not 
 
I N D E 
 
 Y 
 
 =A.o 
 
 Not obtainable from all odoriferous ve- 
 getables, 269 
 
 Thofe of fome aromatics contain their 
 warmth and pungency, 399, feq . 
 of others not, 41 1, feq. 
 
 Their feat, in foft fruits, the rind, 408 
 in feeds of umbelliferous plants, the 
 fhell, 278, 393 
 
 in other feeds, the kernel, 394, 402 
 Obtained by diftillation with water, 270 
 ufe of faline additions, ib. 271 
 
 difadvantage thereof, 271, n. 
 
 Some obtained by diftillation in balneo, 
 
 270 
 
 and with fpirit of wine, 277 
 
 advantages of thefe methods, ib. 
 
 Extracted from rinds of fome fruits by 
 fcarification, 271 
 
 by rubbing on fugar, 409 
 
 Obtained in greatest quantity, from dry 
 fubjeCts, 270 
 
 in greateft perfection, from frefta ones, 
 
 ib. 
 
 How to be kept, 272 
 
 Changes they undergo in long keeping, 
 
 269, 270 
 
 Rectified by a new diftillation, 273 
 Their adulterations how detected, 272, 
 . . . 273 , n - 
 
 Habitude to fire in different circum- 
 ftances, 273 
 
 Require ftronger heat for boiling than 
 water, ib. 
 
 Differences of thofe of different vegeta- 
 bles, 271 
 
 Gravity of different oils, 272 
 
 Light and ponderous from different parts 
 of one plant, 397 
 
 from one and the fame fubjeit, 398 
 Differences in their power as menftrua 
 for Sulphur, 394 
 
 for vegetable colours, 338 
 
 Differences in their folubility in fpirit of 
 wine, 464, n. 
 
 by rectification become more difficult 
 of folution, 464, n» 
 
 the refiduum more eafily foluble than 
 the oil. 
 
 Concrete oils from agallochum, 
 
 . from anifeed, 
 from elecampane, 
 from rue, 
 
 Slue oils from camomile, 
 from milfoil, 
 from pimpinella nigra. 
 
 of thyme digefted with volatile alcali, 
 
 , 439 
 
 Empyreumatic method of diftilling, 464 
 obtainable from all vegetables, 388 
 Exprefled and eflential made empyreu- 
 matic by heat, 273 
 
 Their difference from eflential, 464 
 Made limpid, and freed from their ill 
 - fmell, by rectification, 465 
 
 Soluble in fpirit of wine, 464 
 
 by rectification become more and more 
 foluble, 464, n. 
 
 the refiduum lefs fo, ib. 
 
 Blue from galbanum, 314 
 
 from balfam of copaiba, 285, n. 
 
 Oil from fpirit of wine by vitriolic acid, 454 
 Oils , medicated, 323 
 
 perfumed, ib. 
 
 Oil of almonds, 389 
 
 of Ben, 323 
 
 not lubjeCt to grow rancid in keeping, 
 
 279 
 
 of Bays, 324 
 
 Lin- feed, 278 
 
 Olive, 322 
 
 Rape-feed, 278 
 
 Oleum ecu a Of 324 
 
 de cedro. 271 
 
 de kerva, 324 
 
 kill) mm f ib. 
 
 palma, ib. 
 
 petra, 230 
 
 philofopharum, 231 
 
 pinif 288 
 
 terra, 231 
 
 teda, 288 
 
 Olibanum, , its chemical hiftory, 315 
 
 Onions, chemical hiftory of, 392 
 
 their aCtive principle an eflential oil, ib. 
 Opium, its preparation, 307 
 
 Chemical hiftory, 308 
 
 ACtive parts concentrated, 308, 309 
 diffipated, 309 
 
 Opobalfam, chemical hiftory of, 283, 284, n. 
 
 Ufe as a cofmetic, ib. 
 
 Opopanax, its chemical hiftory, 313 
 
 Orange Flowers , their aCtive principle an el- 
 
 ib. 
 
 fential oil. 
 
 400 
 
 420 
 
 exprefled oils impregnated 
 
 with their 
 
 393 
 
 odour, 
 
 323 
 
 420 
 
 Juice, its acidity concentrated 
 
 in form of 
 
 422 
 
 a cryftalline fait. 
 
 423, m 
 
 408 
 
 Peel , its eflential oil. 
 
 408 
 
 409 
 
 Ores , fulphureous, 
 
 n \ 
 
 ib. 
 
 Arlenical, 
 
 148 
 
 
 4 I ^ 
 
 fome 
 
INDEX. 
 
 fome do not part with their arfenic in 
 calcination without phlogifton, 143 
 Artificial imitations of, 60, 169 
 
 Their metal generally in a ftate of calx, 
 
 i5 2 » n - 
 
 Phlogifton neceffary for reviving it, ib. 
 Afl'ayed by fufton with phlogifton and 
 fufible falts, 113 
 
 General method of running down in 
 _ large, 75 
 
 Fufton of their ftony matter promoted by 
 calcareous earth, 9, n. 
 
 Slags left by former times found to con- 
 tain metal, 75, n. 
 
 Or lean y 433 
 
 Orpiment , its general hiftory, 154 
 
 Adel ted into a red mafs, 155 
 
 Compofed of fulphur and arfenic, ib. 
 Regulus of arfenic obtained from it, 156 
 Its habitude to different acids, 157 
 
 to mercury fublimate, 156 
 
 Whether poifonous, 158 
 
 Its ufes as a pigment, ib. 
 
 Orfeillc, 438 
 
 d’ Avignon , 439 
 
 Orris root , its chemical hiftory, 37 1 
 
 Ojleocolla , a petrified root, 12 
 
 Its production, 12, n. 
 
 Chemical examination, 12, 13 
 
 Calcined and vitrified, 13, n. 
 
 Divided, by wafhing, into calcareous 
 earth and fand, ib. 
 
 Oxymels , 460 
 
 Oxyjacchara , ib. 
 
 Oyfter Jhells, chemical hiftory of, 541 
 
 T) A l NT, fine yellow from vitriol and 
 quicklime, l8i, n. 
 
 Palm oil , 324 
 
 Panacea antimonii , 1 38 
 
 Holfatica , 1 93 
 
 Mercurialis , 1 00 
 
 Paper , incombuflible , from afbeftos, 30 
 
 Pareira brava , chemical hiftory of, 380 
 Parfneps , fugar from, 328, n. 
 
 Parting of gold and filver, 41, 48, n. 
 
 Pearfajh , how prepared, 469, n. 
 
 one of the pureft of the common alcalies, 
 
 ib. 
 
 Pearls , animal calculi, 529 
 
 Different forts and places of production, 
 
 53° 
 
 Their valuation, ' 5 :1 
 
 How cleaned, ib. 
 
 Counterfeited, 332 
 
 Chemical hiftory of, ib. 
 
 Pearl flfncry , 530 
 
 Pearl coloured powder, 109 
 
 Peat , 231 
 
 Different kinds and analvfis, 231, n. 
 
 Pellitory root, its chemical hiftory, 342 
 Peony roots and feeds, chemical hiftory of, 
 
 3 6 ? 
 
 Perfumed oils,- 323, 
 
 Waters and Spirits. 564. 
 
 Pepper black, its chemical hiftory, 416 
 
 JVhite , 4x7 
 
 Jamaica , 414 
 
 Perch-Jlone analyfed, 526 
 
 Per elk) 439 
 
 Peruvian bark) chemical hiftory of, 338, 339 
 Chemical differences from moft other af- 
 tringents, 339, n. 
 
 Petrification in waters, whence, 254 
 
 of vegetables in the earth, 12 
 
 of bones in the earth. 518 
 
 Petroleum) 230 
 
 Petuntfe , an ingredient in China ware, what, 
 
 18, n. 
 
 Pewter , 89, 90 
 
 Phlegm ) what, 247 
 
 Phlogiflon y fee Inflammable principle. 
 
 Phofphori ; luminous in the dark by percufflon ; 
 Flinty 3 
 
 Quicklime faturated with marine acid,, 
 
 226, 16, n. 
 
 Luminous in the dark after expofure to light ; 
 Chalk faturated with nitrous acid, 9 
 Bolognian ftone calcined with phlogif- 
 ton, 19 
 
 Gypfum calcined with phlogifton, ib. 
 Quicklime faturated with vitriolic acid, 
 calcined with phlogifton, 19, n. 
 
 Taking fire from contaSi of air ; alum cal- 
 cined with phlogifton, 188, 189 
 
 From orpiment, iron, and cryflals of 
 filver, 158 
 
 Luminous in the air ; from urine. 579 
 Phofphorus of urine, its difcovery. ib. 
 
 Method of preparing. 579, n.feq. 
 
 the procefs improved. 581, 
 
 How formed into fticks, and made trans- 
 parent. ib. 
 
 Its general properties. 582 
 
 Its flame how extinguifhed. 581 
 
 Renders liquids luminous. 583 
 
 Its habitude to different menftrua. ib. 
 
 to metallic bodies. 583, 584, n. 
 
 Its compofition. 582, n. 
 
 Refolved 
 
N D E- X. 
 
 Refolved into an acid liquor. 584. 
 
 Its acid fuppofed the marine. 582, n. 
 differences from all other acids. 5,84, n. 
 contained in fome vegetables. 577 
 Phofphorus , Balduins, 9 
 
 Black, 188, 189 
 
 Bononian, 19 
 
 Glacial. 579 
 
 Hermetic, 9 
 
 Hombergs, 188, 226 
 
 Scnitillansy 226, 16, n. 
 
 Urens. 
 
 Pifiurejque appearances on liquors, 73, n. 
 
 Pigments , refinous, made foluble, 568 
 
 Pike fifh, jaw bone analyfed, 526 
 
 Pimento , natural hiftory of, 414 
 
 Chemical hiftory, ' 415, 416 
 
 Yields an oil like that of cloves, 416 
 Gives a green tindture to fpirit, ib. 
 
 Pimpinella alba root, chemical hiftory of, 34 1 
 Nigra , 409 
 
 yields a blue oil, ib. 
 
 gives a blue colour to fpirit in diftilla- 
 tion, ib. 
 
 Pitch , how prepared, 288 
 
 various experiments on, 288, 289 
 
 Pitcoal, hiftory of, 244 
 
 Experiments on, 245 
 
 Ufes and inconveniences as fuel, 246 
 Ufe of coaking or charring, 463,11. 
 Plants , fee Vegetables. 
 
 Plajlers , from calx of lead and oils, 58 
 Plajler of Paris , 1 9, n. 
 
 Tinged of different colours, ib. 
 
 Made firmer and more durable, 19,11. 67 
 Makes forged iron fufible, 78, n. 
 
 Platina , chemical hiftory of, 43, n . Jeq. 
 Its agreement with gold, in gravity, in- 
 deftru&ibility, &c. 43, n. 
 
 Suppofed employed for augmenting gold, 
 
 44 
 
 Methods of feparating it from gold, 45 
 
 Its effects on different metals, 
 
 44 
 
 Habitude to acids, &c. 
 
 45 
 
 Plum-tree guniy 
 
 282 
 
 Polypody, chemical hiftory of, 
 
 370 
 
 Pompholyx, 
 
 127 
 
 Poplat-y a refin from, refembling 
 
 ftorax, 
 
 264, n. 
 
 Poppies , extraction of opium from, 307 
 Porce/ane, account of the qualities of different 
 earths in regard to the making of, 
 18, n. 21, n. 
 
 Ingredients of that of China, 18, n. 
 
 Made from green glafs, without change 
 of its figure, 479 
 
 qualities and ufes of this kind of por- 
 celane, ib. 
 
 Glazed black, 80, n. 
 
 blue, 149 
 
 yellow, 51, n. 
 
 Potajhy Rujfta t its differences from other alca- 
 lies, 4^9, n. 
 
 has a large mixture of quicklime, ib. 
 Potatoes , fugar from, 328, n. 
 
 Starch from, 426, n. 
 
 Vinous fpirit from, 450, n. 
 
 Pottery , principles of the art 21, n. 22, n. 
 Poudre des chartreuxy 133 
 
 Precipitates of mercury, 101, 102 
 
 Of metals made by other metals, different 
 from thofe by falts, 103 
 
 One metal revived by precipitation with 
 another, 177 
 
 Precipitation influenced by air, 176 
 Princes metal , 65, 121 
 
 Printers Inky 290, n. 
 
 Metal for types, 1 1 1 
 
 improved, ib. 
 
 Prufian blue , its preparation, 72, n. 
 
 Improved, ib. 
 
 Applied to dying, 73, n. 
 
 Is a calx of iron fuperimpregnated with 
 phlogifton, 72, n. 
 
 A fimilar powder from the afhes of fome 
 vegetables, 468, n. 
 
 Puff-bally chemical hiftory of, 427 
 
 Pulmonariay chemical hiftory of, 380 
 
 Pidvis algarothiy 134 
 
 Pumice Jloney chemical hiftory of, 30, 31, 
 Pungency , of fome vegetables refides in effen- 
 tial oil, 390 yfeq. 
 
 Of others, in a refinous matter, 340 , fcq. 
 
 4 1 1 , f'P‘ 
 
 Of others, in a principle unknown, 426 
 Purgative virtue of vegetables refides in re- 
 finous matter, 337? f e P 
 
 or in faline matter, 327 
 
 Does not arife in diftillation, 274 
 
 Deftroyed by long coction, 268 
 
 Commonly extracted mod perfectly by 
 fpirit, _ 337, feq. 
 
 in fome inftances by water, 360 
 
 Purple-fjhy hiftory of its colouring, matter, 
 
 5 10 
 
 Purple dye, from madder, 388, 
 
 Lake from buckthorn-berries, 433 
 
 Stain for animal fubltances, from folution 
 
 of gold. 
 
 33 ? ft- 
 Stain 
 
N D E X. 
 
 Stain for linen from a fhell-fifh, 510 
 
 Of the ancients, ib. 
 
 Putrefaction, the I ail ilage of fermentation, 
 
 440 
 
 in living animals, 483 
 
 Different in vegetables and animals, ib. 
 Promoted by air and moiffure, ib. 
 
 Prevented, 484, n. 
 
 Animal flefli made fweet after putrefac- 
 tion, ib. 
 
 Putrid fubilances whether alcaline, 485, n. 
 Putty , ... 88 
 
 Pyrethrum , its chemical hiilory, 342 
 
 Pyrites , 1 7 1 
 
 Chemical hiilory of, 174 
 
 Preparation of vitriol from, 175 
 
 white, 149 
 
 Pyrophorus, 158, 188 
 
 See Phofphorus. 
 
 % 
 
 (j\U I C I( L I M Ey its general properties, 
 
 14 
 
 Made into a paile with water, grows 
 hard in the air, ib. 
 
 with glutinous liquors, more than with 
 fimple water, ib. 
 
 mixed with coarfe hard powders, more 
 than by itfelf, 15, n. 
 
 A fingular fpirit in its extinction, 15 
 (perhaps the fame with lime-water,) 
 Quantity diifoluble in water, ib. 
 
 By repeated calcination, totally diifoluble, 
 
 1 5, n - 
 
 Diifolved in water, feparates by air and 
 heat, ib. 
 
 Volatile in diftillation, ib. 
 
 Agreement and difagreement with alca- 
 lies, 15 
 
 Dilfolves fulphur, 167 
 
 the fulphur precipitated by alcalies, 
 
 15 
 
 Corrodes the human calculus, 533, n. 
 Preferves fome animal fubilances. 
 Corrodes linen more than cauftic leys, 
 
 54 ° 
 
 Lofes its acrimony in the air, 15, n. 
 Retains its qualities long if kept moiil, ib. 
 Readily unites with vitrolic acid into 
 felenites, 16, n. 
 
 Diifolves perfedlly in the other acids, ib. 
 Volatilized by the nitrous, ib. 
 
 Extricates the volatile alcali of fal am- 
 moniac without heat, 16 
 
 Renders volatile alcalies permanently 
 fluid, 222 
 
 made to deilroy them, 16, 223 
 Pure contains no fait, 17 
 
 Does not totally precipitate metals from 
 acids, 15, n. 
 
 Does not abforb fulphur from copper and 
 iron ores, 17, 18, n. 
 
 Promotes the fufion of ores, ib. 
 
 Its ufes in the chemical arts, 17 
 
 Stronger from hard Hones than from foft, 
 
 14, n. 
 
 from fea ihells than from mineral Hones, 
 
 54 ° 
 
 Differences in the quality of different 
 limes, 222 
 
 Lofs of weight in calcination, 10, n. 
 
 The lofs fuppofed to be chiefly air, 474, n. 
 Theory of quicklime, and its eft'edls in 
 different experiments, 474? n - 
 
 R. 
 
 D A IN watery 248 
 
 “**■ Rats, deflroyed, 145 
 
 Realgar , 154 
 
 Rectification, of acid fpirits, 180, &c. 
 
 of vinous fpirits, 451 
 
 of eflential oils, 273, n. 
 
 of empyreumatic oils, 465, 492 
 
 Red colours , of flowers , periihable, 43 1 
 Chemical hiHory of, ib. 
 
 The colouring matter of deep red flowers, 
 of a different quality from that of 
 the brighter and rofe red, ib. 
 
 and from the red of orange coloured 
 flowers, 432 
 
 Of Fruits, analogous to that of flowers, 
 
 43 2 
 
 A deep red made yellow by dilution, 338 
 Red dye , from Madder, 387 
 
 Brazil, 386 
 
 Moffes, 439 
 
 Kermes, 508 
 
 Cochineal, 505 
 
 Lacca, 333 
 
 Red Stain on glafs, from iron, 70, n. 
 
 Manganefe, 38, n. 80, n. 
 
 Gold, 37 
 
 Reddle , an iron ore, 80, n. 
 
 Reflningy of gold by antimony, 129 
 
 by folution and precipitation, 45 
 
 of filver by folution and precipitation, 
 
 47, 49, n. 
 
 of Gold and Silver by cupellation, 41, 
 
 106, 112 
 
 Regulusy what, 1 icy 
 
 Regulus 
 
N D E X. 
 
 Regulus of antimony , method of extracting 
 from its ore (viz. from antimony) 1 30 
 Its general properties, ib. 
 
 Volatile in the fire, 13 1 
 
 Deftroys the magnetic power of iron, 
 which other metals only weaken, 
 
 83 
 
 Amalgamated with mercury, 131, n* 
 
 Prepared fo as to be eafily amalgamate* 
 
 ib • 
 
 Calcination and vitrification, 131, 136 
 Its calx not vitrefcible without inflamma- 
 ble matter, 136 
 
 Silver flowers with fal ammoniac, 135 
 Difl'olved in fpirit of fait, 133 
 
 Precipitation by water, vinous fpirit, ni- 
 trous acid, 134. 
 
 Regulus of cobalt , a femimetal fui generis , 152 
 Extrafted from cobalt, l'malt, zaffre, ib. 
 Changed into a deep blue glafs, ib. 
 
 Its habitude to other metallic bodies, ib. 
 How diftinguifhed in ores, ib. 
 
 Habitude to acids, 153 
 
 Changeable-coloured folutions, 152, 153 
 Re fins , their characters, 265 
 
 Exuding from vegetables fpontaneoufly, 
 
 266 
 
 How extracted by art, ib. 267 
 
 Obtained pure from gurnmy-matter, 267, 
 
 268 
 
 Made foluble in water, 283 
 
 Contain a large quantity of oil, 463 
 Are probably coagulated or indurated 
 oils, 269, 282, n. 
 
 Differences in the quality of Refins, 337 
 Are commonly the matrix of the purga- 
 tive and emetic virtues, and of the 
 pungency of fuch vegetables as do not 
 affect the organs of fmell, 337, feq. 
 Common refin, how prepared, 289, n. 
 Rex metallcrum , See Gold. 
 
 Rhapontic , its chemical hiftory, 361 
 
 Rhinoceros's horn , chemical hiftory of, 5 1 1 
 Rhodium wood , its chemical hiftory, 417 
 Rhubarb v differences of Turkey and Eaft 
 India, 360, n. 
 
 Chemical hiftory of its colouring matter, 
 
 36° 
 
 of its purgative virtue, ib. 361 
 
 Monks, 361 
 
 Rifgal, 154 
 
 Rocella, 438 
 
 Roots, feafonof their greateft perfection, 263, 
 
 264, n. 
 
 Rofe leaves , a fuccedaneum to tea, 375 
 
 Rofemary , leaves and flowers chemical hiftory 
 of, 399, 400 
 
 Smell of the flowers confined to the cups, 
 
 ib . 
 
 Rofmarus , tooth, 
 
 Roucou , 
 
 Ruby -glafs, its hiftory, 
 With gold, 
 
 With manganefe, 
 
 Ruby , of arfenic, 
 of fulphur, 
 
 Rue , its chemical hiftory, 
 
 523 
 
 433 
 
 37> 
 
 o 37 
 38, n. 8o, n. 
 
 154 
 171, n. 
 422 
 
 Ruf, prefervation of iron from, 70 
 
 Rye, roafted, a fuccedaneum to coffee, 378 
 
 59 
 
 ib. 
 
 500, n. 
 
 432 
 ib. 
 400 
 
 s. 
 
 O' ACC HA RU M faturni, 
 
 ^ Analyfed by diftillation, 
 the acid not recoverable, 
 
 Saffoiver y 
 
 Red lake from it, 
 
 Saffron , chemical hiftory of, 
 
 Odorous liquor collected in drying it, 401 
 Smell and colour remarkably concealed 
 by fpirit, ib. 
 
 Sagapenum, its chemical hiftory, 316 
 
 St. Johns wort , its chemical hiftory, 371 
 Salts, their general divifion and characters, 
 
 , . 159 
 
 See Acid, Alkali , Neutral. 
 
 Proportion of different falts foluble in 
 water, 256 
 
 Sal ammoniac , compofed of marine acid and 
 volatile alcali, 216 
 
 Whether native, ib. 
 
 Prepared in Egypt, ib. 
 
 Enquiry into the manner of its preparation, 
 
 216, 217 
 
 How purified, 219 
 
 Its chemical properties, 218 
 
 Volatizes metals, H. 
 
 Made fixt, ib. 
 
 Deflagrates with nitre, 218 
 
 Heightens the colour of gold, 43, n. 
 Calls forth the latent colours of glaffes 
 tinged by metals, 38, n. 
 
 Its acid extricated by fubftances which 
 abl'orb the alcali, 225 
 
 Alcali extricated by fubftances which ab- 
 forb the acid, 220 
 
 Volatile fait feparated by fixt alcali, ib. 
 by chalk, 22 1 
 
 its quantity, ib. 
 
 volatilizes a part of the intermedium, 
 221, 222, n. 
 
 the*' 
 
INDEX. 
 
 the pureft of the volatile falts, ib. 488 
 Volatile fpirit, with fixt alcali and water, 
 
 222 
 
 Cauftic fpirit, with quicklime, ib. 16 
 its peculiarities, ib. 
 
 a concrete fait recovered from it, 16 
 Cauftic fpirit with metallic fubftances, 
 
 223 
 
 Dulcified and oily fpirits, 224 
 
 advantage of the cauftic fpirit in thefe 
 compofitions, 16 
 
 Sal ammoniac , nitrous , X 9 7 
 
 Diffolves in fpirit of wine, ib. 
 
 Deflagrates without addition. 
 
 ib. 
 
 Sal ammoniac , vitriolic, fecret or pbilofophic, 194 
 Its chemical properties, 194, n * 
 
 Its action on different metals, ib. 
 
 Diftinguifhed from other ammoniacal 
 falts, ib. 
 
 Sal ammoniacum fixum , 226, 16, n. 
 
 Compofed of calcareous earth and marine 
 acid, ib. 
 
 Its general properties, ib. 
 
 Miflaken for an alcali, 16, n. 
 
 Solution coagulates with alcaline ley, 226 
 Sal antifebrile , i. e. Tart, vitriolat. 202 
 Sal aperitivum, i. e. Sal mar. regen. 225 
 
 Salt bitter purging , hiflory of, 189 
 
 Prepared from bittern of fea- water, 190, 
 
 2x1, n. 
 
 from purging mineral waters, 189 
 Its chemical properties, 1 90, n. 
 
 How diftinguifhed from fal mirabile, ib. 
 Compofed of vitriolic acid and magnefia, 
 
 ib. 
 
 Sal catholicum , i. e. Tart, vitriol. 202 
 
 Salt common , 209 
 
 Whether marine or foflil firft produced, 
 
 210 
 
 Quantity of fait in fea- waters, ib. 
 
 in faline fprings, 2i2, n. 
 
 Bay-falt, where and how prepared, 210 
 propofal for making in England, 210, n. 
 Method of making fait from fea- water by 
 fire, 2 l X 
 
 Sea-water concentrated by cold, ib. 
 Saline-waters concentrated by air, 213 
 Sal gem, account of its mines, 212 
 Chemical differences of fea, brine, and 
 foflil fal t, 2x3 
 
 Their general properties, ib. 
 
 Diiiolved as plentifully by cold as by 
 hot- water, 2ix,n. 
 
 Partof the acid diffipated in evaporation, /£. 
 Volatilized, ’ 213 
 
 Deftroyed, 213 
 
 Compofed of marine acid and mineral 
 a ^ ca fi> 215, 226, n„ 
 
 Regenerated with vegetable alcali, its 
 differences from common fait, 215 
 Different methods of extracting the acid 
 fpinC - 214 
 
 ufes of the fpirit, 21 5 
 
 Dulcified fpirit, ib. 
 
 Quantity of pure acid it contains, 208 
 Salts, compound, compofed of acid and an 
 earth or metal : 
 
 Diftinguifhed from neutral, by alcalies 
 precipitating their earth or metal, 
 
 190, n. 
 
 Vitriolic acid forms with, 
 
 Metals, Vitriols , 173 
 
 Magnefia, Bitter purging Salt , X90, n. 
 
 Argillaceous earth, Alum , 185, n* 
 
 Calcareous earth, Selenites , 8, n. 
 
 Marine acid forms with calcareous earth 
 Sal ammoniacum fixum, 226, 16, n. 
 
 Other combinations not diftinguifhed by 
 particular names. 
 
 Sal Digejlivum , 225 
 
 Sal Diureticus, or terra fol. tart. 46 x 
 
 Sal Ducts Haifa tire, i. e. Nitrum vitriolat. 193 
 Sal de Duobus , ib, 202 
 
 Sal Embryonatum, or Sal marin. regen. 225 
 Salts EJJential , of vegetables, 265 
 
 General method of preparing by cryftal- 
 lization, 278 
 
 The procefs improved, 279 
 
 Nature of the falts, 279, 423 
 
 Sweet falts from the afh tree, 325 
 
 from fugar-cane, 327 
 
 from celeri, 328 
 
 from beet- roots, &c. ib. 
 
 Acid falts, from orange-juice, 423 
 
 from forrel, &c. ib. 
 
 Volatile eflential falts from benzoine, 293 
 from balfam of Tolu, 285, n. 
 
 from balfam of Peru, 286 
 
 from Storax, 291 
 
 Sal Febrifiugum , i. e. Sal marin. regencr. 225 
 Sal Gemma:, 212 
 
 Salt, Glauber's, 193 
 
 Its chemical properties, 190 
 
 How diftinguifhed from the purging bitter 
 fait, ib. 
 
 Compofed of vitriolic acid and mineral 
 alcali, 190, 193 
 
 Sal Hypochondriacum, i. e. Sal marin. regener. 225 
 Sal Indum , of the ancients, 209 
 
 Salt Microcofmic , 574 
 
 Cryfta- 
 
1 
 
 N D E X. 
 
 Cryftallized from urine, 574 
 
 Compofed of volatile alcali, phofphorine 
 acid, (and perhaps fome other principle) 
 Gives out its alcali in the fire, the acid 
 remaining vitreous, 575 
 
 Crepitates not on coals, ib. 
 
 Bubbles and melts like borax, ib. 
 
 Acid does not cryftallize without alcali, ib. 
 Its habitude to metals. &c. 576 
 
 Extradls the phlogifton of fome metals, 
 and forms with it phofphorus, ib. 
 Sal Mirabile, See Salt Glaubers. 
 
 Salts , Neutral , See Neutral. 
 
 Sal Petra, See Nitre. 
 
 Sal P olychrejlum, 202, 1 93 
 
 Sal Prunella, 202 
 
 Sal Sapiential, i. e. Tartar, vitriolat. ib. 
 
 Salt, Sedative , 229 
 
 Its preparation from borax, ib. 
 
 Its properties, 227, n. 
 
 Difficult of folution in water, ib. 
 
 Soluble by heat in fpirit, ib. 
 
 Tinges flame green, 227, 228, n. 
 
 Fixt, vitrefcible, 227, n. 
 
 Volatilized by moifture, ib. 
 
 Not apparently acid, ib. 
 
 Unites with alcalies, and renders them 
 cryflallizable, ib. 
 
 Its compofition unknown. 
 
 Sal volatile narcoticum , 229 
 
 Sand, contains gold, 2, 40, n. 
 
 Extra&ion of the gold, 40, n. 
 
 Yields duller glafs than flint, 2, n. 
 
 red glafs with nitre, ib. 
 
 Sandaracha , 154 
 
 Sandivefy its production, 5, n. 
 
 Similar to Glaubers fait, ib. 
 
 Sanguis draconis , its hiflory as a colouring 
 drug, 299 
 
 Santonicum, 366 
 
 Sap-green, _ 4.13 
 
 Saponaria, chemical hiftory of, 383 
 
 Sapphire , lofes its colour in the fire, 6, n. 
 Sarcocolla , its chemical hiftory, 31 1 
 
 Sarfaparilla , its chemical hiftory, 382, 383 
 Succedaneum to it, 383 
 
 Sajfafras, chemical hiftory of, 418, 419 
 Saturation , what, 159 
 
 Saturnus corneus, 58, n. 
 
 Moft commodious preparation, 581 
 Ufe in the diftilling of phofphorus, ib. 
 Saunders , Red , chemical hiftory of, 337 
 Chemical differences from other red woods, 
 
 337> n. 338 
 
 Its colour by dilution becomes yellow, 338 
 
 Yellow, chemical hiftory of, 
 Scammony, Plant, its hiftory, 
 Railed in England, 
 Gunnny-refin, chemical hiftory. 
 Scarlet-dye , with cochineal, 
 
 Dyed in copper veflels, 
 
 Refufe matter applied to ufe. 
 Different fcarlets with kermes, 
 with Archel, 
 with Brazil, 
 with Gumlac, 
 
 Stains difeharged from, 
 Scordiurn , its chemical hiftory, 
 Schmeerjlein, 
 
 Scrophularia, 
 
 Seeds , green colour of, extradted 
 
 418 
 
 3°3> n. 
 304, n. 
 
 3°3> 304 
 506 
 ib. 
 
 5°7 
 508 
 
 438 
 386 
 334> n. 
 5°7 
 422 
 26, n. 
 
 370 
 
 by fpirit, 
 
 , 397 
 
 not by water, ib. 
 
 In thofeof umbelliferous plants, the fliell 
 
 moft adtive, 278, 393 
 
 in others themedullary part, 278, 394, 
 
 402 
 
 Selenites, 1 9 
 
 Artificial, 8 
 
 Contained in waters, 176 
 
 Semmetals, diftinguifhed from metals, 31 
 
 See Metal 
 
 Sena , qhemical hiftory of. 
 
 Senegal gum 
 Sepia os, 
 
 Shells of fea fifties, confift all of the 
 earth, 
 
 Their earth different from that 
 fifh, 
 
 Analyfis of feveral, 
 
 Shot, how made, 
 
 Silk, made glofly, 227, n. 
 
 Analyfed, 
 
 Silver , its general properties, 
 
 Fixity in the fire, 
 
 Volatilized, 47, n 
 
 Solution in aqua fords, 
 cryftallized, 
 
 precipitation by metals, 47 
 
 ftains it gives to ~ 
 
 358 
 282, n„ 
 
 539 
 
 fame 
 
 54® 
 of the 
 
 484 
 
 540 ,feq. 
 
 55 
 282 
 
 549 
 
 46 
 ib. 
 
 48 
 
 46 
 
 47 
 
 48 
 
 different fubftances, 
 46, n. 
 
 Combination with the marine acid, 48 
 with the vitriolic add, 50 
 
 Difi'olved in fixed alcali, 476, 11. 
 
 in volatile alcali, 489, n. 
 
 precipitated from the volatile by marine 
 acid, not from the fixt, ib. 
 
 Stained by fulphureous vapours, 50 
 
 by fubftances not fulphureous, 430 
 EfFedt of fulphur on it in fufion, „ 50 
 
 4 K ^ feparatiefi 
 
INDEX. 
 
 reparation of the Sulphur, 50 
 
 Changed into a deep blue mafs, by Spi- 
 rit of Nitre cohobated on Quick-lime, 
 
 17,11. 
 
 Its habitude to other metals, 51 
 
 ftrong att;a£fion to Lead, 51, n, 
 
 eliquated from Copper by Lead, ib. 
 abforbed from Iron by Lead, ib. 
 tin abforbed from it by Iron, 86, n. 
 a metallic body not mifcible with it, 
 and which abforbs Sulphur and acids 
 from it, 153 
 
 amalgamation with Mercury, 50 
 Stains Glafs yellow, 51, n. 
 
 Found native, 51 
 
 Its ores, 52 
 
 Extraction from the ore, 53 
 
 Contained in Lead-ores, 53, n. 
 
 Purification, 50 
 
 Receives a cupreous taint from Lead in 
 cupellation, 61 
 
 Made exquifitely pure, 49 
 
 Standard, 51 
 
 Cleanfed externally, 50 
 
 Recovered from fweepings, &c. by amal- 
 gamation, 95 
 
 Suppofed artificially produced, from 
 Lead, 57 
 
 from Pyrites and Chalk, 10 
 
 Imitated on wood by Bifmuth, 1 12 
 
 on Iron, hi, 1 12 
 
 Silvering , cold, 48 
 
 Skeleton!, of fmall animals, commodious way 
 of procuring, 497 
 
 Of the leaves of plants, 428 
 
 Skins of animals, abound with gelly, 552 
 Prepared into Leather, 549 
 
 Analyfed, 550 
 
 Skirret root. Sugar from, 328, n. 
 
 Smalt, method of preparing, 15 1 
 
 From Englifh Cobalt, 152 
 
 Its colour owing to a particular fernime- 
 tal, ib. 
 
 See Regulus of Cobalt. 
 
 Smallage, leaves, feeds, roots, chemical hi- 
 ftory of, 395 
 
 Diftinguifhed from a poifonous plant, 396 
 Smells, of the flowers of plants, often con- 
 fined to the cup, 400 
 
 of the feeds of umbelliferous plants, 
 to the fnell, 278, 393 
 
 of other feeds to the kernel, 278, 394, 
 
 402 
 
 of fome woods, to the heart,. 417 
 
 ©f others, to the bark, 402 
 
 Of vegetables in general refide in an 
 
 eflential Oil, 265 
 
 Of animal fubftances fuppofed to refide 
 alfo in Oil, 482 
 
 Extracted molt perfectly by Spirit of 
 Wine. 
 
 Often concealed by the fpirit, 267, 401 
 Smit, an Iron ore, 80, n. 
 
 Scpe , preparation of, 476 
 
 Tinged green, 477 
 
 With eflential Oils, ib. 
 
 eafy way of making, 477, n. 
 
 Its properties, 478 
 
 Menftrua, ib. 
 
 Sope-leys, 473, n . 
 
 Sope rock, its qualities and ufes, 26, n. 
 
 Sopeivort root, chemical hiftory of, 383 
 A fuccedaneum to Sarfaparilla, ib. 
 
 Soda, chemical hiftory of, 468 
 
 Differences from other vegetable alcalies, 
 
 468, n. 
 
 Blue Fcecula from it, ib „ 
 
 Whether preferable to other alcalies for 
 making Giafs, 469, n. 
 
 Solders , 1 1 j 
 
 Spelter, . 122 
 
 Solubility of bodies, increafed by mixture, 
 
 228, n. 
 
 Diminifhed by mixture, 190 
 
 Sonoroufnefs of metals increafed by mixture, 
 
 66, 85 
 
 i By figure, 54, n . 
 
 Soot , its chemical differences from fmoke, 
 
 4 6 5 
 
 Analyfis, 466 
 
 Ufes, ib. 
 
 Sorrel, its chemical hiftory, 423 
 
 Salt, preparation of, 278, 279 
 
 its differences from Tartar, 423 
 
 analyfis, 424 
 
 Soups , portable , 550 
 
 Spar, a tranfparent calcareous mineral earth. 
 Speckjlein, 26, n. 
 
 Speeularis lapis, _ 18 
 
 Spelter, 1 1 5 
 
 Solder, 122 
 
 Sperma ceti, preparation of, 560 
 
 Chemical hiftory, 561 
 
 Difference from fats, ib. 
 
 Rancid, recovered, ib. 
 
 Spices, whofe pungency is volatile, 400 feq. 
 whofe pungency is fixed, 41 1, feq. 
 
 The odour of all, volatile in boiling wa- 
 ter, ib. 
 
 Spikenard , chemical hiftory of* 420 
 
 Spirits , 
 
I N D E 
 
 X. 
 
 Spirits, Acid, give over their phlegmatic parts 
 firft in diftillation, 180, &c. 
 
 Method of determining their ftrength, 162 
 Spirits , akaline, differences of animal from 
 pure, 488 
 
 Animal fpirits imitated by pure Alcali 
 and Oils, ib. 
 
 Method of diftilling and rectifying, 486 
 How made of uniform ftrength, 487, n. 
 Sophiftications detected, 490, n. 
 
 Spiritus Miindi , 162 
 
 Spiritus nitri beZoardicus, 134 
 
 Spiritus nitri dulcis , its preparation and pro- 
 perties, 455 
 
 Spiritus Jalis dulcis , its preparation and pro- 
 perties, 456, n. 
 
 Spirit , J'moking , of Caff us, 87 
 
 Spirits vinous , differences in them as ffrft di- 
 ftilled, 449 
 
 Methods of determining their ftrength, 
 
 450 
 
 Method of rectifying, 451 
 
 Rettified , all fimilar, ib. 
 
 Criteria of highly rectified fpirits, 452 
 Confift of water, attenuated Oil, and 
 acid, ib. 
 
 Oil feparated from, 453 
 
 Confidered as menftrua, 452, 456, 464, n. 
 Extract all vegetable colours, except 
 blue, " 430, f e( l- 
 
 As vehicles for the active parts of vege- 
 tables in diftillation, 277 
 
 Tinged blue by diftillation from fome 
 vegetables, 409 
 
 Their combination with acids, 453 
 
 Proof. \ how obtained pure, 452 
 
 Their proportion of water and rectified 
 ipirit, 452, n. 
 
 Spiritus Vitrioli pbilofophicus , 1 34 
 
 Spiritus Vitrioli dulcis , its preparation and 
 properties, 453, 454 
 
 Becomes acid by keeping, ' 168 
 
 Oil feparated in the procefs, its qualities, 
 
 454 
 
 Sponge , an animal production, 547 
 
 Its chemical hiftory, 546, 547 
 
 Spurges , their milky juice, 301 
 
 Analogous to Euphorbium, ib. 
 
 Stains , difcharged from fcarlet, 507 
 
 Of Ink or Iron mould from linen, 423 
 Statues , made from foft ftones, and hardened 
 by fire, 26, n. 79, n. 
 
 Stavefacre feeds, chemical hiftory of, 343 
 Steatites, their qualities and ufes, 26, n. 
 
 Steel, is Iron faturated with phlogifton, 78 
 
 Is Iron in an intermediate ftate between 
 caft and forged, 79, n. 
 
 Made from caft Iron, ib. 
 
 from forged Iron, 78 
 
 Its qualities, 79, n. 
 
 Tempering, ib. 
 
 Colours it aflumes from heat, ib. 
 
 differences in quality depending there- 
 on, ib. 
 
 Changed into Iron again, ib. 
 
 Of the ancients, 79, n. 
 
 Sternutatory powders , 348 
 
 Stoechas yellow, its chemical hiftory, 372 
 Arabian, its chemical hiftory, 321 
 
 Stones , ftained of different colours, 46, n. 
 Penetrated by tinging fumes, 7 
 
 Artificial ftains diftinguifhed from natural, 
 
 46, n. 
 
 Hard graven ftones of antiquity, 79, n. 
 were probably in a fofter ftate when 
 cut, 80, n. 
 
 Storax, its chemical hiftory, 290 
 
 Whether factitious, ib. 
 
 A refin fimilar to, from Poplar buds, 264 
 Storax , liquid, its hiftory, 291 
 
 Stypticum heroicum, 182 
 
 Sublimate corrojive Mercury , 98 
 
 Not adulterable with Arfenic, 142 
 
 Fallacy of methods propofed for diftin- 
 guifhing adulteration, ib. 
 
 Suet , analyfed, 560 
 
 Sugar, how prepared, 327 
 
 Refined, 328 
 
 Candy, brown and white, 329, n. 
 
 Extracted from different European plants, 
 
 328, n. 
 
 Its chemical properties, 329 
 
 Ufe for colouring liquors, 
 
 ib. 
 
 Sulphur, compofed of vitriolic acid and phlo- 
 gifton, 164, 167 
 
 Its acid transferred into alcalies, 
 into earths, 
 into metals, 
 
 167 
 
 16 
 
 N3 
 
 Proportion of acid and Dhlogifton, 167, 
 
 168 
 
 Artificially produced, 
 
 164 
 
 Its acid feparated by burning. 
 
 166 
 
 methods of collecting. 
 
 ib. 
 
 collected in large quantity. 
 
 166, n. 
 
 obtained in a volatile ftate. 
 
 167 
 
 Its general properties, 
 
 i6 5 
 
 Sublimation, 
 
 ib. 
 
 Made fomewhat tranfparent, 
 
 125 
 
 Colour heightened, 1 6‘- 
 
 j, 107, n. 
 
 Habitude to acids. 
 
 167 
 
 4 K 2 
 
 
N D E X. 
 
 Diflolved in alcaline ley, 167 
 
 in volatile fpirits, 168 
 
 in Lime-water, 167,15 
 
 in Oils, 168 
 
 different diffolving power of different 
 Oils, ( 168, 169 
 
 Precipitated from alcalies by acids, 167 
 from Lime-water by fixtalcalies, 167, n. 
 Abforbed from fixt alcalies by fome Oils, 
 
 169 
 
 Its effeCls on different metals, 169 
 
 order of its affinity to metals, ib. n. 
 its adhefion to metals, ib. 
 
 Its ufes, 170 
 
 Natural hiftory, ib. 
 
 Contained in pres, 17 1 
 
 Whether contained in the air, 172, 
 Method of extracting from its proper 
 ores, 17 1 
 
 Red, 170 
 
 Sumach , Venice , 385 
 
 Its qualities as a dying drug, ib. 
 
 Swallow-wort root, its chemical hiftory, 367 
 Sweetnefs in vegetables, refides in a faline 
 matter, 425 
 
 Diffoluble by fpirit and by water, ib. 
 Obtained in greateft purity by fpirit, 
 
 280, n. 
 
 Sylvejler , its difference from Cochineal, 507 
 Sympathetic Ink. Vide Ink. 
 
 Powder , 182 
 
 T. 
 
 CTJcamahacca tree, railed in England, 294, n* 
 Fragrant balfam from its young buds, ib. 
 Refm, chemical hiftory of, 295 
 
 Talk , general characters of, 27 
 
 Diftinguifhed from fubftances refembling 
 it, 28, 18 
 
 Melted by a burning glafs, 28 
 
 Run with Salts and other earths into ele- 
 gant glaffes, 28, 29, n. 
 
 Solar, 29 
 
 Tallow analyfed, 5.59 
 
 Talus leporis analyfed, 528 
 
 Tanning , ufe of Oak-bark, 549, n. 
 
 Supplied by other vegetables, 550, n. 
 
 Tar , how prepared, 288 
 
 Additions for rendering it more durable, 
 
 289, n. 
 
 Tartar , contained in -Wines, 446 
 
 Produced by fermentation alone, 457 
 Leaft plentiful in Wines that have been 
 leaft perfectly fermented, ib. 
 
 Its feparation from Wines, 456 
 
 Purification,, 457 
 
 l 
 
 General properties, '4^7 
 
 Agreement and difagreement with native 
 acid vegetable Salts, 423 
 
 Differences of its acid from the acetous, 
 
 457, n. 
 
 Diflodged from alcalies by the acetous, /£. 
 Solubility promoted by all the fubftances 
 combinable with it, ib. 
 
 Its habitude to metals, ib. 458, n. 
 
 Analyfed by fire, 458 
 
 Extemporaneous alcaline Salt from it 
 with Nitre, 203 
 
 Tartarus emeticus , 137 
 
 Nitratus , 202 
 
 Tea , its culture and curation, 372 
 
 Chemical hiftory, 377 
 
 An extraCl retaining its flavour, ib. 
 
 Subftitutes, 37- 
 
 Terra Japonica , chemical hiftory of, 317 
 Foliata nitri , 205 
 
 Turtari, its preparation, 461 
 
 Tloerma, 252 
 
 Thermometers , do not meafure variable heat, 
 
 Hi 
 
 Thyme , its Oil made blue by digeftion with 
 volatile fpirits, ^3^ 
 
 Thymiama bark, chemical hiftory of, 292 
 Tin , its general characters, 85 
 
 Phsenomena in the fire, 85, n. 
 
 Calx unvitrefcible, ip, 
 
 the bafis of enamels, ib. 
 
 Its differences from Lead, 86 
 
 EffeCts on different metals, 85 
 
 Abforbed from Silver by Iren, 86, n. 
 Contains Arfenic, ib. 
 
 Its crackling probably owing to Arfenic, 
 
 87, n» 
 
 Habitude to different acids, 87 
 
 Aqua regia its proper menftruum, ib.. 
 Inquiry into its folubility by vegetable 
 acids, 88, 460, n. 
 
 Solution heightens many vegetable and 
 animal reds into fcarlet, 506, &c. 
 Permanent folution of it for the fcarlet 
 dye, 506'. 
 
 Recovered from the fediment of the 
 fcarlet dye, 50 7 
 
 Corroded by alcalies, 88 
 
 Medical hiftory, ib. 
 
 Account of its ores, 89 
 
 Manner of affayjng and fmelting them, ib. 
 Lead mixed with it, how diftinguifhed, 90 
 Tincal, 227 
 
 T.inftures of vegetables in vinous fpirits, 267 
 General obfervations on, ib. 
 
 The 
 
I N D E X. 
 
 The fmell of the fubjeCt often concealed 
 by the fpirit, ib. 
 
 Not purely refinous, 267 
 
 Colour heightened by alcalies, 474 
 Of Antimony , 1 40 
 
 Of Corals 545 
 
 Of Sulphur , 167 
 
 volatile , 168 
 
 Tobacco, its chemical hiftory* 355 
 
 Topaz, experiments on, 6, n. 
 
 Fufible with Borax, ib. 
 
 not with Alcali or Nitre, ib. 
 
 with calces of Lead and Copper, ib. 
 with Chalk, 6, n. 
 
 Torment'd root, chemical hiftory of, 362 
 Tortoifejhell , chemical hiftory of, 513 
 
 How figured, 513,11. 
 
 Stained, 5 * 4 > n * 
 
 Tragacanth Gum , its hiftory and ufes, 281 
 Differences from other Gums, 282, n. 
 Train-oil , chemical hiftory and analyfis, 562 
 Tripoli earth, 25 
 
 Various experiments on, 25, 26 
 
 Turbith mineral, 97, 1 02 
 
 Diifolved in water, 97, n. 
 
 Root, its chemical hiftory, 354 
 
 Turcois, artificial, 518 
 
 Diftinguifhed from natural, 518, n. 
 
 Turf, _ 231 
 
 Turmeric root, chemical hiftory of, 384, 388 
 Its qualities as a colouring drug, ib. 
 Tuirnfol, how prepared, 433 
 
 Turpentines , different forts, 280 
 
 Chemical hiftory of, 287,288 
 
 Turpeth. Vide Turbith. 
 
 Tutenag, 1 X 5 
 
 Tutty, enquiry into its origin, 125 
 
 Various experiments on, 127 
 
 U. 
 
 T rNicorrt s horn, its hiftory and analyfis, 
 C 7 528 
 
 Urine, its nature and ufes, 574, 578 
 
 Differences from temperature, aliments, 
 
 . 577 
 
 Contains marine Salt, 574 
 
 Diftillation of volatile fpirit and' Salt, 578 
 Microcofmic Salt how prepared from it, 
 
 575 
 
 Phofphorus how prepared from it, 579 
 
 V. 
 
 Y/' Adrian root, its chemical hiftory, 368 
 * Vapours, inflammable, 70,11.117 
 
 Forming a cloud in the air,, 195, 
 
 Varnijbes , deftroyed by weather, 257 
 
 Their drying promoted, 184 
 
 nnioer, black, 235, 236 
 
 Lac, 334 
 
 Orange coloured, 433 
 
 Hard, tranfparent, for metals, 70, n. 
 
 Camphorated, their ufe, 32c 
 
 Solution of Copal for, 299, 11. 
 
 Vegetables, their ftruCture, 260 
 
 Differences from foil, climate, ib, 
 
 and age, 263 
 
 Principles of their rational culture, 261 
 Their pabulum, 262, n. 
 
 Imbibe Salts from the foil, 262 
 
 Whether they imbibe metals, 263, n. 
 
 Contain Iron, ib. 
 
 Whether capable of imbibing colours, ib. 
 Seafon of the greateft perfection of their 
 different parts, 263, n. 
 
 Different kinds of juices in which their 
 qualities rcftde, 264 
 
 naturally extravafated, 266 
 
 extradfed by art, ib. 
 
 purified from one another, 266, 280 
 Their prefiding fpirit, 265 
 
 Their colours often altered or deftroyed, 
 in drying, by the fun’s light, 
 preferved in hafty exficcation by fire, 
 
 430 
 
 Their odorous parts generally not vola- 
 tile in the fun’s heat, 274, n.. 
 
 diffufed through the air by virtue of its 
 own diffolving power, ib. 
 
 The atmofphere impregnated with vege- 
 table principles net volatile in the heat 
 of boiling water, 274, 11 . 275, n. 
 Fragrance of flowers deftroyed by pref- 
 fure, 280 
 
 Their refolution by fire, 462- 
 
 different vegetables refolved into ftmi- 
 lar principles, 281 
 
 Vegetations, artificial, 177, 194, CSV. 
 
 Arbor Dianes, 47 
 
 Regular effiorefcences in piano, 47, n. 
 
 Verdegris , preparation of, 6 3 
 
 Purified by cryftallization, ib. 
 
 Divers experiments, on, 64 
 
 White metal from, 64, n. 
 
 Its ftrong acid fpirit, 64 
 
 Veronica , its chemical hiftory, 379 
 
 A fubftitute to Tea, ib. 375 
 
 Vincetoxicum root, chemical hiftory of, 367 
 Vinegar , its production, 458 
 
 Strongeft from the m oft fpirituous Wines, 
 
 44 e 
 S harpnefs-. 
 
N D E X. 
 
 Sharpnefs increafed by certain additions, 
 
 343 
 
 Method of determining its ftrength, 462 
 Table of the ftrength of different Vine- 
 gars, ib. 
 
 Its difcriminating characters, 462, n. 
 
 Recovered from flight corruption, 459 
 Its analyfis, ib. 
 
 Concentration, 461 
 
 As a menftruum for metallic bodies, 460 
 recovered from Copper in a concen- 
 trated ftate, 64 
 
 not from Lead, 500, n. 
 
 Medicated, 460 
 
 Vipers analyfed, 550 
 
 Virgins Milk , 294 
 
 Viride montanum, 227 
 
 Vitriols of different kinds, 173 
 
 Their production, ib. 
 
 Method of preparing them, 174 
 
 Native, 177 
 
 Confiff of Copper, Iron, Zinc, or mix- 
 tures of them, united with the vitriolic 
 acid, _ X 73, feq. 
 
 Copper how difcovered in, 181 
 
 Converfion of one kind into another, 177 
 Adhefion of the acid in different Vitriols, 
 
 178 
 
 Analyfis of different Vitriols, 180 
 
 Diftillation of the acid, ib. 
 
 its colour whence, ib. 
 
 rectification, 180 
 
 Of Iron, ox green, 179 
 
 Its preparation at Deptford, 175 
 
 General properties, 179 
 
 Changesproduced by repeated folution, ib. 
 Spontaneous feparation of the Iron, 179 
 Ufes in dying, &c. 181, 182 
 
 Of Copper, ox blue, 182 
 
 Manner of preparing, 183 
 
 Its properties and ufes, 182, 183 
 
 Of Zinc , or white , its preparation at Ram- 
 melfberg, 177 
 
 Analyfis, 183 
 
 Properties and ufes, - 184 
 
 Mixt, 173, 180 
 
 Vitriolated Nitre, X 9 3 
 
 Vitriolated Tartar , different methods of pre- 
 paring, J92 
 
 Its chemical characters, 190 
 
 Volatilized, 191, 247 
 
 Its acid transferred into other bodies, 
 
 172, n. 
 
 The acid difiipated, fo as to leave the 
 alcal.i pure, 475 
 
 Volatility of bodies, promoted, fee Fixed. 
 Diminished, 218 
 
 W. 
 
 JJ/’^fers, coloured with red Lead, 55, n. 
 
 Lead revived from them, ib. 
 
 IVafps, contain an acid, 498 
 
 Water , diffufed through all the kingdoms of 
 nature, 247 
 
 The bafts of all liquids, ib. 
 
 Conffant circulation of it, ib. 
 
 Carries off fixt bodies in its exhalation, ib. 
 
 259 
 
 Its fubtility, incompreflibility, porofity, 
 
 254 
 
 Fluidity not owing to particles of fire, 255 
 How influenced by cold and heat, ib. 
 Is the bafis of flame, ib. 
 
 As a menftruum for Salts, 255 
 
 Quantity of different Salts it diflolves,256 
 Superimpregnation with Salts, 257 
 
 As a menftruum for vegetable and animal 
 fubftances, 257, 267 
 
 Its aCtion on oils, varnifhes, &c. 257 
 
 Imbibes the aCtive principle of eflential 
 ods, 265, n. 
 
 Its aCtion on metals, 258 
 
 on ftones, ib. 
 
 By the mediation of other fubftances dif- 
 folves all bodies, ib. 
 
 Leaves an earth in diftillation, 258 
 
 Waters, Common , 248 
 
 At?nofpherical , ib. 
 
 Pond, 249 
 
 River , 248 
 
 Spring, ib. 
 
 Their differences, ib. 
 
 Differences in regard to brewing, 448 
 Hardnefs, to what owing, 249, n. 
 
 fmall degrees of, difcovered, ib. 
 
 cured, ib. 
 
 Gravity of different waters, 254 
 
 Marks of purity, 259 
 
 Impure corrected, ib. 
 
 Prefervation, ib. 
 
 Liquor for preventing putrefaCtion, 251 
 Which leaft difpofed to putrefy, 249, n. 
 Stinking, made fweet and potable, 269, n. 
 Waters Mineral, probably contain no vola- 
 tile fpirit, 176, 177 
 
 Experiments illuftrating their impregna- 
 tion, ib. 
 
 Hot, accounted for, 74 
 
 Tranfpofitions and new combinations of 
 their contents in the procefs by which 
 
 they 
 
INDEX, 
 
 they arc feparated, 176 
 
 Artificial imitations of, ib. 
 
 Method of inveftigating their contents, 
 
 252, 253, n. 
 
 fallacioufnefs of experiments by mix- 
 ture, ib. 
 
 Arfenical, 254 
 
 Bituminous, ib. 
 
 Chalybeate, 175 
 
 Petrifying, 254 
 
 Purging, _ _ ’ * 75 , i8 9 
 
 Water, fea, its general qualities, 249 
 
 Quantity of Salt in that of different feas, 
 
 210 
 
 Its bitternefs, from bitter purging Salt, 
 
 250 
 
 Methods of feparating' its Salts, 2 io,feq. 
 Made fweet and potable, 250, 251, n. 
 Waters , d'jiilled , manner of preparing them 
 from different kinds of vegetables, 
 
 - , 2 . 73 > fit- 
 
 Inquiry into the proccfs of diftilling wa- 
 ters by the heat of the fummer’s 
 fun, 274, n. 
 
 Inquiry into the ufe of cohob at ion, 
 
 276, n. 
 
 Wax , chemical hiftory of, 332 
 
 Whitened, ib. 
 
 Diffolved in Spirit of Wine, ib. 
 
 Analyfed by diftillation, ib. 
 
 Weld , as a dying drug, 434 
 
 Whalebone , analyfed, 516 
 
 Wheat , Indian, Sugar from its ftalks, 328,11. 
 Whey , Sugar from, 572 
 
 White flowers produce colours with different 
 mixtures, 432 
 
 IVhites of Eggs, chemical examination of, 554 
 Changed by drying into a fubftance like 
 Amber, ib. 
 
 Render oily and refinous fubftances mif- 
 cible with water,. 
 
 Boiled hard, liquefy in a moift air, 555 
 gummy-refins, added to them, diffolve 
 in the liquamen, 317 
 
 pure Reims not, ib. 
 
 Whiting , * 8 
 
 Whortleberry leaves, fubftituted to Tea, 375 
 
 Wines , 
 
 441 
 
 Dangerous fophiffications difcovered, 
 
 446, 60 
 
 Fined by Ichthyocolla, 554 
 
 whether wholefome, ib. 
 
 Grape Wines imitated by juices of other 
 fruits, 445? 44 2 
 
 Characters of good Wine, 446 
 
 Chemical analyfis, ib. 
 
 Account of the principal Wines drank in 
 Europe, 443 
 
 Table of the contents of different Wines, 
 
 44? 
 
 Altered irrecoverably by the reparation of 
 any of their principles, 447 
 
 Concentration by freezing,. ib. 
 
 whether advantageous, 448 
 
 Wood, its preparation, 437 
 
 Manner of dying blue with it, 438 
 
 Blue Fecula from it, analogous to Indigo, 
 
 ib. 
 
 Wood, vitriolefcent, 174 
 
 Prefervation of, 182 
 
 Preferved from taking fire, 
 Stained like Boxwood, 
 Stained black, 
 
 Woodlioe , chemical hiftory of, 
 Wool, analyfed, 
 
 Philofophic, 
 
 46 7 
 
 158 
 
 3^5 
 
 502 
 
 549 
 
 1 1 5, n. 
 
 Worms, Earth, chemical hiftory of, 500 
 Worms , prey firft on the gummy parts of ve- 
 getables, leaving the more adtive Refin, 
 
 353j 393 ’ 403 
 
 Wormfeed, chemical hiftory of, 766 
 
 Wonnwood, ' 407 
 
 Its bitternefs obtained free from its ill 
 fmell, 3164 
 
 y Y haloes, 
 Xylobalfam , 
 
 X. 
 
 Y. 
 
 n n. 
 
 420 
 
 284 
 
 Arrangement of, according to their fer- 
 mentation, 442 
 
 Colouring of Wines, 445, 329 
 
 Curation, flavouring, ib. 
 
 Obfervations on the keeping of them, 
 
 445 
 
 ' 'Y'Ellow colour of flowers durable, 431 
 Extraiffed by water and fpirit, ib . 
 
 Variations in the lhade from different 
 mixtures, 7^ 
 
 In orange-coloured flowers, of the fame 
 quality as in the pure yellow, 432 
 In flofeuli, the fame as in the petala, ib. 
 In the flarina, of a different nature, ib. 
 Yellow dyes, _ 434,431,384 
 
 Paint forhoufes, from Vitriol and Lime, 
 
 i8i,n. 
 
 otain for Glafs, from Silver, &c. See Glafs. 
 Yolk of Eggs. See Eggs. 
 
 Z. Yaffle , 
 
I N D 
 
 z. 
 
 *7 J ’ffre y hiftory of. 
 
 Method of preparing. 
 
 150, n. 
 150, 151 
 
 Its colouring matter a particular femi- 
 metal, 152 
 
 See Regulus of Cobalt. 
 
 Zarnichy 154 
 
 Zedoary , its chemical hiftory,. 41 1 
 
 Zincy its general properties, 1 1 5 
 
 Changes of colour from long fufion, 
 
 115, n. 
 
 Deflagration in the fire, ib. 
 
 Sublimation into flowers, 115,116 
 the flowers fixt, 115, n. 
 
 vitrified, ib. 
 
 An Oil extricated by them from Vine- 
 gar, 118,119 
 
 revived, 116, 117 
 
 E X. 
 
 Its effects on different metals, 120 
 
 Changes copper yellow, ft. 
 
 Deflagrates with and volatilizes metals, 
 
 1 21, n. 
 
 Amalgamation with Mercury, 120 
 Refills Sulphur, I2r, n. 
 
 Hepar Sulphuris, ib. 
 
 Antimony, 121, n. 
 
 Phenomena with Nitre, ib. 
 
 Soluble in all acids, 117, u8 
 
 Diflolvcdin alcalies, 118, 121, n. 
 
 Precipitates moft other metals from acids, 
 . 119 
 
 Extricates cauftic alcali and marine acid 
 from Sal ammoniac, 1 19, 120 
 
 Method of obtaining at Goflar, 1 22 
 Its ore. Calamine, Vide Calamine. 
 
 Medical hiftory, 128 
 
 FINIS, 
 

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