^%> 
 
 gotietn of ®votb$mi$*. 
 
 PRESENTED BY 
 
 
• 
 
 /• 
 
 
 ^ 
 
THE 
 
 Elaboratory laid open, 
 
 OR, THE 
 
 SECRETS 
 
 OF 
 
 modern*ch!mistry 
 
 AND 
 
 PHARMACY 
 
 REVEALED: 
 
 Containing many Particulars extremely neceffary to be known 
 to all PraSfitioners in Medicine. 
 
 
 ^ 
 
 LONDON* 
 
 Printed for J. Nourse at the Lamb oppofite Kathcrine-Stnet 
 in the Strand. MDCCLVIII. 
 
"f 
 
 
 • *••. 
 
PREFACE. 
 
 TH E particulars, which make the prin- 
 cipal contents of the following pages, 
 were known to me in confequence of fome 
 opportunities, that feldom happen to .any, 
 who are willing to impart to the pub- 
 lic, what they learn of this kind : a minute 
 knowledge of fuch matters being, almoft 
 wholly, confined to thofe, who are lucrative- 
 ly engaged in the bufmefs they relate to ; and 
 who, therefore, have very ftrong reafons 
 againft revealing them to the world ; as their 
 profits, in a great meafure, depend on keep- 
 ing the fecrets of this fort, in few hands. 
 Nor is there indeed, any individual, amongft 
 thofe moft verfed in the practice of chemiftry 
 and pharmacy, who can boaft of being ac- 
 quainted with more than a part of what I 
 have here colle&ed, or communicated; as 
 each has only a certain fhare of Arcana ; and 
 is, in general, even no further mafter of them, 
 than in barely being able to perform the pro- 
 cefles, by certain ftated means ; without any 
 deeper intelligence either of the nature of the 
 operation or fubje<fl : and fome of the very 
 material articles, moreover, have not, as far 
 A 2 as 
 
ii PREFACE. 
 
 as I am informed, been hitherto known to, or 
 pra&ifed by, any other perfon than myfelf ; 
 though, from a very fuffitient experience, I 
 am fully convinced of their utility. 
 
 It having happened to me, however, from 
 my indulging a great fondnefs for every branch 
 of medicinal knowledge, and fome peculiar 
 circumftances of lituation favourable in this 
 particular point to my defire, to become ap- 
 pnfed of a! moil all the more fecret practices, 
 ufed by thofe who prepare or vend medicines, 
 I conceived it might be beneficial to the pub- 
 lic to make them known ; and to give the 
 world a more juft and full view of the me- 
 thods, by which the gveateft part of the che- 
 mical medicines to be commonly met with 
 are prepared, than had been before done; 
 efpeclally, if the proceffes were illuftrated 
 with fuch obbfervations, on. the nature of 
 the feveral fubje&s, and manner of- oper- 
 ating, as might enable any, who would take 
 the pains to underftand what I have laid be- 
 fore them, to vary each procefs, in fuch man- 
 ner as mav fuit any particular purpofe or oc- 
 cafion ; or to judge with greater certainty of 
 the genuineness or perfection of any medi- 
 cines, they may receive from the hands of 
 thofe who prepare or fupply them. 
 
 Others have, indeed, frequently profefied, 
 to have done die fame in fome degree, both 
 in books, and courfes of lectures : but they, 
 who have been moft qualified to treat thefe 
 matters fpecuiatively, have feidom had any 
 
 2 very 
 
PREFACE. iii 
 
 very accurate information of the real methods 
 of management, in the elaborates of thofe 
 few great dealers, who almofl monopolize 
 the preparation of the grea'eft part of the 
 confiderable art'cles of the chem'cal cla r s of 
 medicines: while they, on the other hand, 
 who have been moft largely concerned in 
 the practice, have found themfelves very little 
 capable of extenfive fpeculation ; as it muft, 
 neceffarilyj be the refult of refearches, con- 
 ducted by more profound and abftrafted 
 principles than come within their cognizance. 
 I have therefore, availing myfelf of the 
 advantages, that have fain to my lot, with 
 refped: to both thofe kinds of knowledge, 
 effayed to give a juft and critical view of the 
 preicnt ftate of the operative pharmacy, efpe- 
 daily as it depends on chemiftry: and to 
 fhew, how the common preparation of me- 
 dicines, particularly thofe of the retail chemifts 
 and druggifts, who are furnifhed with almoft 
 every article they vend by the vdiolefale pre- 
 parers of, or dealers in them, as alfo nearly 
 the whole of what is fent into the country, 
 differs from the regular and orthodox pre- 
 fcriptions. That all the perfons, trading either 
 in a more extenfive or confined way in medi- 
 cines, being put on the fame level, with refpedt 
 to the arts ufed in the preparation of them, 
 may regulate their proceedings accordingly; 
 and not lye under a neceffity of repofing an im- 
 plicit confidence in others ; of which in general, 
 advantages, not very fair, however cuftomary, 
 are taken. A 3 In 
 
iv 
 
 PREFACE. 
 
 In the profecution of this defign, I found it 
 neceffary, in order to the rendering intelligible 
 what I would communicate, *to go further than 
 meerly giving a hiftory of the methods prac- 
 tifed for the more profitable preparation or fale 
 of medicines ; or detached obfervations on 
 them. I therefore have prefixed an introduc- 
 tory effay, on the improvements of the inftru- 
 ments and general methods fubfervient to the 
 intentions both of chemiftry and pharmacy : as 
 alfo an examination into the famenefs of the 
 real nature of feveral fubftances in the materia 
 medica, which go under different names, and 
 are fuppofed to have an eflential diverfity: that 
 it may be more readily underftood, on what 
 grounds, fubftitutions are deemed fit to be per- 
 mitted : and I flatter myfelf, that this part of 
 my work may have a further benefit, than the 
 bare elucidation of the fubfequent matter $ as 
 it may tend to inculcate a deeper knowledge of 
 principles, which, though extremely requifite 
 to all who concern themfelves with the prepa- 
 ration of medicines, is yet almoft univerlally 
 wanting in them. 
 
 Whatever fuccefs I may have, in attempting 
 to give new lights into the modern practice of 
 this part of pharmacy ; I {hall not, I am afraid, 
 be thanked by thofe, who are moft largely con- 
 cerned in the preparation, or fale of medicines, 
 for the whole of this work : as nothing can be 
 more difagreeable to any fuch body of men, 
 than to have the myfteries of their art, or trade, 
 difplayed to the world : but if they would re- 
 
 fleft 
 
PREFACE, v 
 
 fled what treatment any fpeculative perfon, 
 who had made the moft confiderable difco- 
 veries, would meet with from them, if he 
 endeavoured to reap a benefit from his ftu- 
 dies, in any way where they fhould be con- 
 cerned; they would find no room to compiain> 
 becaufe he gave himfelf the pleafure of im- 
 parting, to the public, the fruits of his labour 
 for the general good of mankind ; when all 
 other means of advantage were denied to 
 him, through their oppofition, or felfifh con- 
 dud, fhouldhe go about to feek any. I could 
 furnifh very ftrong inftances in fupport of the 
 truth of this fuggeftion, if the common maxims 
 of trade did not put it out of doubt. 
 
 However, the greater dealers in medicine (to 
 all of whom, I difclaim the leaft obligation, 
 and againft fbme of whom, I have the jufteft 
 caufe of refentment,) may take umbrage at the 
 liberty, I affume, of laying open the fecrets of 
 their trade, the more retail venders will, I am 
 certain, be greatly obliged to me : fince, I put 
 it in their power either to infift, in many cafes, 
 on a more perfect commodity j or to fave fixty 
 or eighty per cent, by preparing, themfelves, 
 the fame they are now fupplied with $ as well 
 as to diftinguifh, in other articles, how far the 
 prices, charged to them, correfpond with the 
 quality of what they buy. 
 
 But it was not for the benefit or pleafure, of 
 either the wholefale or retail preparers, or ven- 
 ders of medicines, I principally intended this 
 work : the whole body of praditioners in phy- 
 
 A4. fie 
 
vi PREFACE. 
 
 fie are greatly interefted in this kind of infor- 
 mation; and fome claffes have very litt e op- 
 portunity of furnifhing themfelves with it, how- 
 ever neceflary. It is, therefore, to thole who 
 prefcribe or admlnifter medicines, as well as to 
 thofe who prepare or fell them, Ideiign to make 
 thiscolle&ion ufeful : that knowing the ieal man- 
 ner of preparation of what they may generally 
 meet with, as well as the common fubftiturions 
 and adulterations, with the nature of each, and 
 meansof detecting them, they mayguard againft 
 material impofitions ; and yet not give them- 
 felves the unneceffary trouble, of combating de- 
 viations from meer forms, where there is no ef- 
 fential reafon for a ftrict compliance with them. 
 It may be faid, that feveral of the particu- 
 lars, I have introduced, are not difcoveries of 
 new matter; having been before mentioned, in 
 the works of others, though fomewhat dif- 
 ferently. I admit the cha ge ; but, in my 
 juftification, alledge, that few of thefe have 
 been treated of, in fo full and diftinft a man- 
 ner, as was*heceffary to render them ufeiul in 
 practice : as they have, for the moft part, been 
 only touched on (lightly, in f me of thefe vo- 
 luminous compilements of common proceffes, 
 and trite obfervations on them, which have 
 been fo multiplied, that both the time left in 
 perufing often the fame matter, and the 
 expence of purchafing fiich a number of 
 books, on the fame fubjefr, alike in the greateft 
 part of their contents, have prevented the 
 fmall portion of them, which, is new, from 
 
 being 
 
PREFACE. vii 
 
 being known to many. I hope, therefore, it 
 will be allowed, to be neither unfair or impro- 
 per, to have given a place here, in a more ex- 
 plicit view, to fuch of thefe particulars as may 
 be confidered real improvements ; even though 
 they have been before hinted at, in the coj ner 
 of fome other book ; and with regard to fuch 
 others as concern w r hat ought to be exploded 
 out of praftice, I have mentioned them, in 
 order to explain intelligibly the means, by 
 which they may be diftinguifhed. Some things, 
 indeed, I have round it unavoidable to take in, 
 though without any plea of novelty; becaufe 
 they were wanting to complete the fyftem, fo 
 far as was neceflary for the illuftration of the 
 other parts : as, particularly, I found it necef- 
 fary, in order to fhew clearly the comparative 
 advantage or impropriety of the private methods 
 of preparing the feveral medicines, with the re- 
 gular and authorized procefles, to infert the 
 latter; which, for the brevity of the work, I 
 fhould otherwife rather have chofen to have 
 left out. But, after all, I have been the greateft 
 plagiary againft myfelf ; the moft material part 
 of the theft, I have committed, being from my 
 own performances. 
 
 There are fome articles ufually prepared, by 
 thofe who pra&ife medicinal chemiftry, that 
 are chiefly ufed by the farriers ; as the crocus 
 metallorum, and white precipitate, as made 
 by the old procefles : and there are, alfo, 
 others, of which, the greateft or whole con- 
 fumption is in purpofes intirely foreign to me- 
 dicine 7 
 
iiiv Preface. 
 
 dicine ; as the oil of vitriol, aqua fcrtis, yellow 
 arfenic, &c. but I thought proper, to take 
 them all into my collection, where I could im- 
 part any material fecrets relating to them; fince 
 it may be of advantage to thofe, who, by 
 dealing in medicines, are fometimes almoft un- 
 avoidably led to deal in thefe preparations like- 
 wife : and, as the lights, I fhall give concern- 
 ing them, tend alfo to illuftrate the general 
 principles of chemical knowledge, and the 
 whole I fay of them does not occupy any great 
 part of the book, I hope others will excufe me. 
 It may, probably, be remarked, by thofe, 
 who are lefs interefted in that part of this 
 work, which regards the teaching how to 
 conduit the chemical procefles with extraor- 
 dinary profit and difpatch, that I have de- 
 fcended to too minute particulars ; and taken 
 up too much room in the detail of matters, 
 not univerfally inftrudtive : efpecially in the 
 obfervations, I have made, with refpeft to the 
 operations in general, and the directions for 
 the conftructing of furnaces, and other parts 
 of the apparatus. But thofe, who look into 
 this book with a more fpeculative tafte, muft 
 pafs over this part - y and excufe it for the fake 
 of others, who, having the advantages at- 
 tending the practice more immediately in 
 their regard, may greatly profit by it. And 
 I can venture to affirm, that many of thofe 
 cautions, which may feem moft trivial on a 
 flight view, will, on experience, be found of 
 very high confequence in the conduit of the 
 2 operations. 
 
PREFACE, m 
 
 operations, where large concerns come in 
 queftion : for the quantity of what is produced, 
 as well as the redu&ion of the expence, are 
 no lefs material, in a commercial light, than 
 the quality. Nor is there perhaps any, that 
 fhall have occafion to build or refit an elabora- 
 tory, but who may reap a benefit by con- 
 fidering the inftruftions I have laid down 
 with relation to the furniture of it : as they 
 are neither founded on conjectural reafon- 
 ings, nor an implicit confidence in the com- 
 mon ufage ; but on an experimental know- 
 ledge of the fubjeCt, they concern, acquired by 
 many expeniive trials of a variety of methods, 
 aided by a clofe ftudy of thofe principles which 
 lead to a juft theory. In giving fuch inftruc- 
 tions on this head, as can at all avail in prac- 
 tice, it is unavoidable to be very circumftantial 
 in every material point. For, from an igno- 
 rance of one neceflary part of what is to be 
 done, the whole may be found impracticable, 
 to thofe, who have no guide but the directions 
 before them : and I have, therefore, endea- 
 voured to lead fuch, as take upon them the 
 fuperintendance of this neceflary work, fo ftep 
 by ftep, to the right execution of it, that, with- 
 out previoufly conceiving what the whole ftruc- 
 ture maybe when finiihed, they may proceed, 
 in the due formation of the feveral parts, free 
 from the leaft perplexity or embarraflment. 
 
 I may probably, be, likewife, charged, with 
 not having intirely acquitted myfelf of the pro- 
 mife, implied in the title of this work, becaufe, 
 
 I 
 
x PREFACE. 
 
 I have concealed fome particular practices, in 
 the fophiftication of medicines, which, I ac- 
 knowledge myfelf to be informed of. But, 
 as the defign of this part of the book was, to 
 difcover and explode impofitions, and not to 
 introduce or propagate them, I thought it much 
 better, to fupprefsa few of thofe, which are moft 
 injurious, and moft likely to be perfued by per- 
 fbns now ignorant of them -, and, in ftead of fhew- 
 ing how they may be effectuated, to teach enly 
 the method of detecting them. For I am afraid, 
 a greater attention may be given, to what I 
 exhibit of this kind, by thofe, who are inquifi- 
 tive after fuch wicked arts, in Grder to reap a 
 perfonal benefit from adopting them, than by 
 thofe, who can have no other motives to feek 
 this fort of knowledge, but the good the pub- 
 lic may derive from their detecting them : and, 
 to the latter clafs, it is indeed fufficient, to un- 
 derftand what relates to this only. 
 
 I could have written a more methodical and 
 comprehenfive treatife, on the fubjeft I have 
 taken in hand, had I gone into a more general 
 difquifition of every thing relating to it : but 
 as my defign was to fupply only what feemed 
 hitherto wanting, I reduced my plan to fuch 
 a form, as might beft avoid the repetition of 
 what has been already frequently faid, and 
 confined my view to fuch particulars only, 
 as are either not to be found elfewhere, or 
 would yet well bear a further elucidation.- 
 This being the fole obje<ft of my perfuit, I 
 contented myfelf with the giving up the ele- 
 gance 
 
PREFACE. xi 
 
 gance of the compofition for the utility of 
 concifenefs \ and to place the merit of the 
 book, rather in the choice of the matter, than 
 the extenlivenefs of the plan : as I think I may 
 fafely give the readers, the fatisfadtion of this 
 afTurance ; that, if this book does not contain 
 every thing relative, in a general view, to the fub- 
 jeft, which is to be found in fome others be- 
 fore publifhed, it, neverthelefs, contains fome 
 very material articles, that are not to be found 
 in any. 
 
 CON- 
 
CONTENTS. 
 
 PART I. 
 INTRODUCTION. 
 
 FX P L A IN I N G the general matters pre- 
 , v^oufly neceffary to be known, both with 
 refpecl to the operations, and fubjeft of them, 
 in order to the more ready comprehenfion of 
 the fubfequent particulars. 
 
 SECTION L 
 
 Defcription of fever al improved parts of the che- 
 mical apparatus, conducing to the more quick 
 and expedite manner of performing many of the 
 proceffes. p. i. 
 
 SECTION II. 
 
 General obfervations, on the mojl eafy and profita- 
 ble methods of performing fever al of the opera- 
 tions of chemi/iry and pharmacy. 5 3 
 
 SECTION III. 
 
 Examination of the famenefs of fever al fubflances, 
 which make a part of the materia medica un- 
 der different denominations \ without any effen- 
 tialdiverfity: being neceffary for the determin- 
 ing, how far many fubjiitutions are allowa- 
 ble. 66 
 
 Of 
 
CONTENTS. 
 
 PART II. 
 
 Of the preparation of chemical medicines ; with 
 the feveral fubftitutions and adulterations 
 pra&ifed in regard to them j and the means 
 of their deteftion. 
 
 SECTION I. 
 
 Of the preparation ofthofe medicines , where f aline 
 fubjlances make the whole or principal part of the 
 Jubjetf. p. 85 
 
 SECTION II. 
 
 Of the preparation ofthofe medicines, where vege- 
 table fubjlances make the whole or principal part 
 ofthefubjeSl. 123 
 
 SECTION III. 
 
 Of the preparation of medicines, where fofjile fub- 
 jlances, not metalline, make the whole, or prin- 
 cipal part of thefubjeSl. 155 
 
 SECTION IV. 
 
 Of the preparation ofthofe medicines, where metal- 
 line fubjlances make the whole > or principal part 
 of thefubjeff. 208 
 
 SEC 
 
CONTENTS. 
 
 SECTION V. 
 
 Of dijiilkd waters and fprits. either not generally 
 known, or to be mcu \ by cheater or more cutn- 
 \fendioiu methods than ar$ direfted in ihrrcgu-* 
 lar py ejcnptionsjor them. P • 3 3 * 
 
 PART vi. 
 
 Of galenical preparations, where deviations arc 
 ufually made from the prefcriptions of the 
 college ; or .where iophiffcications -are fre- 
 quently pra&ifed. 
 
 PART IV. 
 
 XL 
 
 Of the fubflitutions and .adulterations, com- 
 monly praftiied with refpeft to the fimples ; 
 and the proper methods of detecting them 
 in each inflance. 351 
 
 i» *-* 
 
 ERRATA. . 
 
 Page 17, line 12, for it was therefore owing to thefe obfeure, read, 
 it was, therefore, to thefe obfeure. P. 1 3-, 1 16, for four 
 ounces, r. four pounds, P. 145, I/16, {ox f pint of alcohol, 
 r.fpirit or alcohol. P. 1 79, 1 4, for as well that, r. as well 
 as that. P. 197, 1. 6, for lacfalfhuris, r. lac fulp l uris. 
 P. 198, 1. 8, for falfulphuris, r lac/ulphuris. P. 246, 1. IO, 
 for ficlitious cinnabar, x. f adit I ous cinnabar. P 249. 1. 3. for 
 tile be laid over, r. tile being laid ever. P. 253, for jin 
 butter, r. cinnabar, and butter. P. 287, 1. II, for for the 
 folution, r. or the Joint ion, P. 304, for ficlitious Roman vitriol, 
 r. factitious Roman vitriol. 
 
 PART 
 
PART I. 
 
 INTRODUCTION, 
 
 Explaining the general matters previ- 
 pufly neceffary to be known, both 
 with refpedt to the operations, and 
 fubjedt of them, in order to the 
 more ready comprehension of the 
 fubfequent particulars, 
 
 SECTION I, 
 
 Defer iption of fever al improved parts of 
 the chemical apparatus \ conducing to 
 the more auick and expedite manner 
 of performing many of the proce/Jes. 
 
 THE fifft attention, neceffary to the 
 performing, with mpft e$fe and pn> 
 fit, the feveral operations of chemijk 
 try and pharmacy, is, the inftrurnents 
 employed in them : for, on the perfection of 
 thefe, depend not only the quick difpatch of 
 the bufinefs undertaken, but alfo considerable 
 favings in labour, fewel, and frequently the 
 produce of the operation. It is, indeed, to 
 happy inventions refpefting this point, that 
 gj-eat part of the advantage of the prefent prac^ 
 
 B tie* 
 
2 INTRODUCTION. 
 
 tice over the former lies ; and that fome few 
 particular perfons have been able to afford me- 
 dicines, even though duly prepared, at extreme 
 low prices. So that^ without being well inform- 
 ed of the inftruments, by which compendious 
 procefles may be performed, general directi- 
 ons, for the conducting them, would in many 
 cafes be of very little avail : and to defcribe 
 the ftrudiure of each of fuch as ferve for a va- 
 riety of purpofes, or to fhew the princi- 
 ples of its general utility, on every particular 
 occafion, would lead into a detail repetition, 
 tedioufly immethodical. I (hall, therefore, 
 here endeavour, to point out all thofe particulars, 
 relating to the beft conftruftion and formation 
 of the feveral parts of the apparatus, which give 
 any fuperiority over the common methods; as 
 well fuch as have been praftifed in a fecret way 
 by others, as thofe, which my own reafoning 
 and experience have led me to the knowledge 
 of 5 avoiding at the fame time as much as pof- 
 lible to dwell on any matters, which are com- 
 monly known, as my prefent bufinefs is not to 
 teach the whole art of pharmacy, but only to 
 impart thofe improvements, that have either 
 been intirely concealed hitherto, or well un- 
 derftood only by fome few. 
 
 But, however neceffary it may be to the com- 
 pletion of my purpofe, it is extremely difficult 
 to give fuch defcriptions in words, however 
 multiplied, of any new parts of an apparatus, 
 for purpofes of this kind, as may enable thofe, 
 who have never ken them, to conceive their 
 
 ftruc- 
 
INTRODUCTION. j 
 
 ftru&ure and ufe clearly enough, to introduce 
 them into practice ; nor do engraved defigns 
 greatly affift in this point \ for, though they 
 convey a general idea of the figure, yet they 
 help but little in teaching how to form or con- 
 ftrudl machines of a more complex kind. On 
 which account, I fhall endeavour, fit ft, to lead 
 to a diftinft notion of the improvements, I fhall 
 attempt to teach, by fhewing the defects and 
 impropriety of the fame fubjefts, according to 
 the methods at prefent in ufe : that, by thus 
 reafoning on what is already underftood, I may 
 facilitate the comprehenfion of the principles on 
 which a greater perfeftion may be founded : 
 and, having thus introduced a general notion of 
 what I would recommend, I fhall fubjoin par- 
 ticular dire&ions for the pra&ice of it. 
 
 Of furnaces in general, with the defers ofthofe 
 at prefent in ufe. 
 
 The principal, and moft critical, part of the 
 apparatus lubfervient to pharmacy is, the fur- 
 naces employed for the preparation of thofe 
 medicines, which come within the chemical 
 clafs : as the ftru&ure of thefe is more com- 
 plex, and the ufes they are applied to of a more 
 nice and difficult nature, by far, than any other 
 of the operations regarding this art. It is 
 therefore neceffary, that they fhould be well 
 defigned, and judicioully executed ; otherwife 
 their defeats greatly enhance the expenee, and 
 fruftrate the intention, of the operations they 
 
 B 2 arc 
 
4 INTRODUCTION. 
 
 are to perform ; befides their being extremely 
 liable to become, in a very fhort time, out of 
 repair and ufelefsJy ruinous. 
 
 It is proper, therefore, that careful and able 
 men fhould be employed in the fabrication of 
 furnaces ; though fuch are rarely to be found 
 among common workmen : but the moft likely 
 to fucceed are thofe, who have either been em- 
 ployed before in the fame bufmefs, or have 
 been accuftomed to fet coppers for houfhold 
 purpofes. When the beft qualified, however, 
 are fet to work, they fhould be continually fu- 
 perintended by the operator, or fome perfon 
 capable of judging, both of their adherence to 
 the plan given, and general performance of 
 the work. For, if the parts of furnaces, that 
 are expofed to much heat, be not made ex- 
 tremely compa<ft; but are patched up of mor- 
 tar and bricks, that are not fitted in every part 
 to each other, (as bricklayers are very apt to do 
 from the habits they acquire by being employed 
 in coarfer buildings) the mortar will very loon 
 calcine, and fhrink, in fuch faulty places ; and 
 make fuch vacuities and inlets to the air, as 
 render the furnace incapable of doing properly 
 its office, to the great delay and, fometimes, 
 deftrudlion of the procefs. 
 
 The materials are the next obje£t of atten- 
 tion ; and they ought to be well chofen, and 
 perfed: of their kind. Common bricks, with 
 good mortar made with lime and coal afhes, 
 well mixt and beaten together, will ferve for 
 thofe parts, which are not liable to be heated 
 
 red 
 
INTRODUCTION. 5 
 
 red hot; but: where that degree, or a greater, 
 may happen, Windfor bricks and Windfor 
 loom, or Sturbridge clay, and lime, or, where 
 the fire may be very violent, the compofition, 
 called the fire lute, (hereafter mentioned) fhould 
 be ufed. And as the Windfor bricks are of a 
 texture, which admits of it, they fhould be fo 
 worked to fit each other, as to form one corn- 
 pad: body with fcarcely any joints at all. 
 
 Particular care fhould be likewife taken, in 
 the drying of furnaces. For the beft defigned 
 or conftru&ed may be eafily fpoiled by any 
 mifmanagement in this point ; as is very fre- 
 quently the cafe, where the ufe of them being 
 wanted, as generally happens, before they are 
 ready, they are not allowed a proper time. 
 The interior part fhould be, therefore, fuffered 
 to fettle and dry, for fome days, before the ca- 
 vity be clofed in by finifhing the upper : and, 
 after that part alio be become pretty firm, they 
 fhould be gradually warmed by a fmall char- 
 coal fire, made, either in the body of the fur- 
 nace itfelf, or in the afh-hole under it. After 
 this has been fome time continued, and the 
 mortar appears hard in the interior furface, a 
 coal or wood fire may be made, of a gentle de- 
 gree at firft 5 and increafed flowly, as the fmc- 
 king of the furnace may indicate to be proper. 
 But the more leifurely this proceeds, the more 
 durable and perfed: will be the furnace. 
 
 Notwithftanding the great importance of 
 commodious furnaces to the practice of the 
 chemical pharmacy, the methods, in general 
 
 B 7 ufed 
 
6 INTRODUCTION. 
 
 ufed for their conftru<5tion, are furprizingly de- 
 fective: and in purfuance, therefore, of the 
 defign, I have propofed, of illuftrating the di- 
 re&ions, for the execution of the improvements 
 I offer, by pointing out the faults in the fame 
 fubjefls according to the manner now in prac- 
 tice, I will endeavour to (hew the feveral er- 
 rors committed with regard to them ; and hint 
 on what principles they may be avoided : re- 
 ferring, however, the more particular explana- 
 tion of the proper remedy, in each cafe, till I 
 come to give the improved plan for the con- 
 ftru<5lion of the feveral particular kinds. 
 
 The firft and mod obvious fault is the dif- 
 pofing the fireplace in the midft of the fur- 
 nace, inftead of putting it under the center of 
 the obje£t, intended to be heated. By which 
 means, the fire exerts its greateft force on the 
 column of brick over it ; calcining and deftroy- 
 ing all that part of the furnace, without an e- 
 quivalent effect on what it is intended to aft 
 upon. This improper difpofition of the fire 
 may, however, be eaiily avoided, and a right fi- 
 tuation fubftituted, if the worm flew be omit- 
 ted ; and the other methods followed, which I 
 have given in the particular plans : and as the 
 inconveniencies, refulting from this error, ex- 
 tend as well to thofe of ftills and boilers, as of 
 other furnaces, an undue confumption of fewel, 
 and auick deftruftion of the furnace, being al- 
 ways difadvantageous, it will be found worth 
 while to endeavour to remove them in all 
 pafes : efpecially, as it may be done with- 
 out 
 
INTRODUCTION. y 
 
 out producing any other ; except, where im- 
 menfely large veffels are in queftion ; which re- 
 quire unavoidably a fupport of brickwork un- 
 der them. 
 
 The next fault, in the prefent ftrufture of 
 furnaces, is the want of fome proper inlet for 
 feeding the fire, without having occafion al- 
 ways to open the door for that purpofe. For, 
 where the fewel can only be thrown in at the 
 door, there is a neceffity for having the area of 
 the fireplace large, otherwife a fufficient quan- 
 tity cannot be made to lie in it ; as, if it be 
 fmall, the coals tumble out, whenever it is fill- 
 ed to any greater height, every time the door is 
 opened. Now the diladvantages, confequential 
 to the having the fireplace too large, are mani- 
 fold. For if the fpace, occupied by the bars, be 
 great, and the whole area, they make, be co- 
 vered with coals, the heat will be too ftrong on 
 many occafions; and, if it be not covered, a 
 falfe draught is made, which greatly weakens 
 both the degree and efieft of the fire propor- 
 tionably to the quantity of fewel : as the in- 
 flux of the air will be the greateft through 
 the naked part of the area, which much weak- 
 ens the draught through the coals, at the fame 
 time, it greatly refrigerates both the furnace 
 and its contents : fo that, not only a great 
 wafle of fewel is made, but the latitude in the 
 degrees of heat, and means of accommodating 
 it to the occafion, which are to be had in fur- 
 naces well conftrufted, are here greatly limited. 
 This defeft may be remedied by making a pro- 
 
 B 4 per 
 
8 INTRODUCTION. 
 
 per hole, Hoping towards the fire, fome inches 
 above the furface of the fewel when at the 
 higheft : it muft be lined with an iron frame* 
 fuch as is, with its ftopper, below defcribed, and 
 may be in dimenfions about four inches long 
 and three high ; and fituate in the front of the 
 furnace, directly over the opening for the door 
 and afh-hole. Through this hole, the fire may 
 be fed by a {hovel of a fit fize and figure, or 
 ftirred with a poker properly bent, without 
 ufing the door for thofe purpofes ; which need 
 therefore only to be opened, for the making 
 or lighting the fire, or the freeing the bars, 
 from the fcoria or clinkers, when they are 
 choaked up with them* When the hole is not 
 opened occafionally, the ftopper muft be kept 
 in ; which fhould fo fit, as to make the fide 
 of the furnacte equally intire as if there were 
 no fuch hole. This manner of feeding the fire 
 will be found a very great convenience to 
 thofe, who are accuftomed to it : as the effectual 
 draught of the furnace may be thence greatly 
 increafedj the lighting the fire much facilitated, 
 and the operator likewife enabled to have what 
 body of fewel he pleafes in the furnace, and 
 to adequate the heat, with certainty, to any 
 occafion, without either being fubjed: to have 
 the fire extinguifhed, when it is kept low, or 
 not admit of being raifed high, without- the 
 falling out of the coals, already in the furnace, 
 every time he attempts to throw in a frefh 
 fupply. When this device is ufed, the area of 
 the bars may be diminished at leaft one half; 
 
 and 
 
INTRODUCTION. ^ 
 
 &nd the confumption of fewel will be leffened 
 much more than in that proportion, for the 
 reafons before given ; nor will the operation be 
 checked, on any negledt of the operator in 
 keeping up the fire ; as is liable to happen* 
 when furnaces are built in the common way. 
 Another great error in the building fur- 
 naces, particularly thofe for harts-horn pots* 
 or fand-potSj is the carrying the fire rpund the 
 objeft, to be heated, in a vermicular flew, or 
 worm (as it is commonly called) ; by which 
 means, the veffel intended to be heated is much 
 longer before it attain a due degree of heat ; 
 as the principal force of the fire is exercifed on 
 that great mafs of brickwork, which forms the 
 worm, and is brought into equal contiguity 
 with the veffel itfelf, in refpeft to the fire, with 
 indeed a much greater furface expofed to it ; 
 from whence it requires a proportionable quan- 
 tity of fire to keep the whole in any ftated de- 
 gree of heat, Befides the great delay, therefore, 
 in the beginning of the operation, which can- 
 not proceed till the whole mafs, that makes the 
 worm, be brought to a certain heat, the due ef- 
 fect cannot be had, without the confuming a 
 much greater proportion of fewel, than if the 
 heated veffel hung in the open furnace. But 
 there is yet another momentous inconvenience, 
 arifing from furnaces of this kind of fti ufture, 
 where a ftrong heat is wanted, which is, that 
 the brickwork of thefe worms is extremely fub- 
 je£t to be damaged, and fall to pieces : from 
 whence the flew being choaked up, and the 
 
 draught 
 
io INTRODUCTION. 
 
 draught obftrufted, a neceffity arifes of taking 
 down all that part of the furnace, if not the 
 whole ; and rebuilding it at a great expence ; as 
 there is no poffibility of repairing it, under thefe 
 circumftances. An intire open cavity carried 
 round the pot, ftill, &c. formed by railing the 
 brickwork, at an equal diftance, on every fide, 
 and clofing it in where no further heat is re- 
 quired, anfwers the end much better : fuffer- 
 ing the proper objed: to be immediately fur- 
 rounded by the fire ; and placing it out of the 
 contadl of other bodies, fo as to be capable of 
 being independently heated ; while the furnace 
 itfelf is much lefs liable to be damaged, or can 
 fuftain a fmall degree of damage, without any 
 material injury to its ufe ; and even, when it is 
 fo injured as to require repairing, admits of it 
 with greatly lefs trouble and expence, than 
 when built in the other method. 
 
 The laft fault, I (hall take notice of, with 
 regard to the common ftrufture of furnaces, is, 
 the bad proportion of the chimnies j which, in 
 general, are greatly too large. By making them 
 {by the draught is much diminished ; and the 
 foot fuffered to be collefted in a troublefome 
 manner. For, when the fides of chimnies con- 
 tain a greater area of furface than can be duly 
 heated, the neceflary rarefa<5tion of the air, 
 pafiing through, is destroyed ; on which prin- 
 ciple alone the draught of chimnies depends ; 
 and, the cavity being too large proportiq- 
 nably to the current of air, the force of it is 
 fo climinifhed, that the foot, inftead of being 
 
 blown 
 
INTRODUCTION- n 
 
 blown out, gathers and refts on the fides, till 
 it obftru&s the paffage ; and, choaking up the 
 draught, deadens the fire, efpecially at the firft 
 lighting of it ; by which means, the progrefs of 
 the operation is fometimes greatly retarded. 
 Inftead, therefore, of the wide proportion now 
 made ufe of, if the chimney be intended for the 
 ufe of one furnace only, a fquare of fix inches 
 is fully fufficient ; and this may be increafed, 
 in an equal ratio, where it is designed for a 
 greater number : and there will refult this fur- 
 ther advantage, from forming them on this 
 proportion, that they will not require to be 
 raifed half fo high, as when made in the com- 
 mon way. 
 
 Of the iron-work necejfary to be prepared, previ- 
 oujly to the building furnaces in general. 
 
 An iron door, with its frame, for the light- 
 ing the fire and taking out the fcoria of the 
 coals, is requilite for moft kinds of furnaces : but, 
 as fuch doors are commonly intended, for the 
 further ufe of feeding the fire with fewel, they 
 are made much larger than is neceflary, if that 
 method be, as I above advifed, exploded. It is 
 proper, always, to have them as long as the fire- 
 place, or area made by the bars ; but they need 
 not be more than four inches high, where they 
 are not defigned to ferve for feeding the fire. 
 For, the lower they are, the lefs they will be 
 capable of injuring the proper draught of air, 
 through the fewel, by making a falfe one : and 
 
 the 
 
ia INTRODUCTION. 
 
 the lefs liable, alio, they will be, themfelves, to 
 warp and be out of order. They fhould be 
 made of hammered iron, and ftrong. The u- 
 fual form will very well ferve ; if the latch, to 
 keep them fhut, be made bigger than com-' 
 mon ; and carried acrofs the whole door, to give 
 it ftrength to refift the weight of the fewel ; 
 which, other wife, when the iron is foftned 
 by violent heat, forces the middle part out- 
 wards. 
 
 The form of the bars for bearing the fewel 
 is, likewife, frequently faulty. The length 
 muft be always as that of the whole area of 
 the fireplace - y but the breadth fhould be only 
 a quarter of an inch : though, to give them a 
 due ftrength, they may be made half an inch, 
 or more, deep. They fhould be laid at a quar- 
 ter and half quarter of an inch diftance ; and 
 fixed firmly into two ftrong crofs bars at each 
 end of them : which crofs bars fhould be fuf- 
 ficiently long, to admit of their fuffering the 
 brickwork to have good hold of them ; and 
 fhould be alio beaten flat, at their ends, for that 
 purpofe. This faftnefs of the parts to each 
 other is neceffary, in order to the tearing out, 
 with lefs hazard, the fcoria of the coals, which 
 fometimes choak the paffage of the air betwixt 
 the bars in a very detrimental manner; as alfo 
 to make them bear to be ftruck when clogged 
 with afhes : neither of which means, of afiift- 
 ing the fire, can be pradlifed, in common fur- 
 naces, without fome hazard of difplacing the 
 bars, and putting the furnace into fome prefent 
 
 diforder. 
 
INTRODUCTION. 13 
 
 diforder. The bars fhould be of good ham- 
 mered iron ; becaufe it is difficult to procure 
 them to be properly caft, of due dimenfions, 
 from pig iron : but if the bars and frame could 
 be eafily fo procured, in one intire piece, they 
 would anfwer extremely well ; efpecially where 
 the heat is not fo intenfe, as to hazard the melt- 
 ing any part" of them. 
 
 A proper iron frame and ftopper are necef- 
 fary to be provided, for the hole through 
 which the fire is to be fed with fewel, when 
 the method of doing that by means of the 
 • door is not followed. The frame muft be 
 made of the fize and form of the hole ; which, 
 as I obferved before, may be four inches long 
 and three, high;, or bigger where the furnace 
 is large. It may be formed of four plates of 
 a moderate ftrength ; of which, the two up- 
 per, muft Hope downwards to the fire, in the 
 fame parallel, according to the figure of the 
 hole ; and they muft slfo project beyond their 
 joining with the fide plates, in order to their 
 being fixed in the brickwork. The ftopper 
 fhould be formed of five plates, put together in 
 fafhion of a box (as in the doors of portable 
 iron furnaces), and of fuch figure and propor- 
 tion as to Hide into the hole, and fill it fo ex- 
 actly, as to render that part of the furnace in- 
 tire, when it is not taken out occafionally. The 
 hollow of this box muft be turned towards the 
 fire, and filled with fire lute; and a handle 
 fhould be fixed in the middle of the inward 
 part, for the more commodious ufe of it when 
 x hot. 
 
14 INTRODUCTION. 
 
 hot. This frame and ftopper may be beft made 
 of hammered iron ; as it is difficult to procure 
 things of fo complex a form to be cafl pro- 
 perly ; and the ftopper would likewife be ne- 
 ceflarily heavier, if made of pig iron, on ac- 
 count of the unavoidable thicknefs of the parts 
 of caft work. 
 
 Plates, and broad bars, are alfo generally 
 wanted* to be laid where brickwork is to be 
 raifed over the hollow parts of furnaces. Where 
 larger plates are required, the cheapeft and beft 
 way is to have them caft of the exadt dimen- 
 fions wanted : but, when a broad bar, or two, 
 laid together, will anfwer the end, the eafieft 
 way is to have them cut off, of a proper length, 
 from the bars of hammered iron, at the iron- 
 mongers. Thefe plates, or bars, fhould be pro- 
 cured, of a due magnitude, before the furnace 
 be begun : the right proportion of them may 
 be eafily computed, by eftimating the propor- 
 tion of the parts of the furnace they are to be 
 fubfervient to; which fhould be always care- 
 fully done ; and the workmen apprized, by 
 written inftrudtions, of the fize and meafure of 
 every thing, they are to ereft, or put together. 
 
 Of the beft manner of conftruEling furnaces for 4 
 the fand-pot and fand-bath* 
 
 This is the moft important and ufeful fort of 
 
 furnace : which, I fhall therefore treat of more 
 
 particularly, becaufe, in theufuai way of building 
 
 them, they are not only defective and faulty, in 
 
 i all 
 
INTRODUCTION. 15 
 
 all the general points before mentioned ; but 
 in others, alio, refpeding the proper proportion 
 of this particular kind. This furnace is intend- 
 ed to ferve, for the fublimation of falts, and 
 diftillations of all kinds performed in retorts. 
 It heats at the fame time, when advantage- 
 oufly conftrudted, a fand-pot and fand-bath. 
 In the firft of which, any operation may be 
 performed in one retort, where the degree of 
 heat required is, from that of boiling oil to the 
 firft degree of glowing heat, or what is called 
 red hot. In the latter may be performed any 
 five feveral diftillations, or diftillations and di- 
 geftions, where different degrees of heat are 
 required, from that of boiling fpirits of wine, 
 to that of boiling oil -, as the bath may be made 
 large enough to contain five retorts, or other 
 veffels of the fame magnitude ; which, by being 
 placed nearer or more remote from the fand- 
 pot, or fixed higher or lower in the fand, may 
 fuffer the feveral degrees of heat each fhall re- 
 quire. 
 
 The firft ftep, towards making this furnace, 
 is, to procure a proper fand-pot, and large plate 
 for forming the fand-bath. The fize of the 
 fand-pot muft be determined, by the magnitude 
 of the retorts, or bodies, intended to be ufed in 
 it. It muft be fo proportioned, as to hold the 
 retort, and to allow about two inches fpace for 
 the fand to furround it on every fide. The beft 
 form of fand-pots is, that of a cylinder with a 
 concave bottom, which ought to be made dou- 
 ble the thicknefs of the fides 3 but the com- 
 mon 
 
16 INTRODUCTION. 
 
 mon pots are generally made conical; I fuppofe, 
 for the freeing them more eafily from the 
 moulds, they are caft upon ; and with thin bot- 
 toms, which fubje&s them to be very foon 
 worn out if expofed to a ftrong heat. 
 
 The plate for the bath fhould alfo be of caft 
 iron; and muft be proportioned to the fize, and 
 number, of retorts or other veffels,propofedtobe 
 worked in it. It muft be long enough, to allow at 
 leaft two inches fpace betwixt every retort, and 
 two inches and a half betwixt them and the fides 
 of the bath. For the breadth, the fame propor- 
 tion muft be obferved, with the addition of 
 two inches for its bearing on the fides of the 
 hollow it is to cover. It may be as thin as it 
 can be well caft ; but care muft be taken, not 
 to break it in the moving or fixing, which may 
 otherwife very eafily happen. A flat ring of 
 iron of about three inches breadth, and of a 
 proper magnitude to receive the edge of the 
 pot into a proper groove, made in its own inner 
 edge, fhould alfo be provided. An iron door, 
 with its proper frames, and bars, for the fire- 
 place, as alfo an iron frame, and ftopper, for 
 the hole for feeding the fire, with other bars 
 and plates for the hollow parts of the furnace, 
 muft likewife be prepared, according to th$ 
 directions above given. After which, the parr 
 ticular manner of conftru&ing the whole muft 
 be as follows. 
 
 The dimenfions of the farnace muft be firft 
 fettled, by this method ; which will ferve alfo 
 for obtaining thofe of any other kind of fur- 
 nace 
 
INTRODUCTION. 17 
 
 nace defigned to be built, where the objedt to 
 be heated is of a conftant or fixed nature. The 
 diameter of the fand-pot, intended to be ufed, 
 being firft taken, fix inches muft be added to 
 it, for the cavity round the pot, and the length 
 of two bricks, to allow for the thicknefs of 
 the fides of the furnace. Thefe, being put to- 
 gether, give the diameter of the whole furnace. 
 To find the due height, the height of the pot 
 muft be firft taken ; to which muft be added 
 eight inches, for the diftance betwixt the pot 
 and furface of the fire when higheft, fix inches, 
 for the depth of the fireplace, and eight inches, 
 for the diftance of the bars from the ground of 
 the aih-hole, with the height of a brick, for a 
 courfe that muft be carried round the edge of 
 the pot, which, being all put together, give 
 the height of tfye whole furnace from the foun* 
 dation, 
 
 A round cavity muft then be made, in the 
 ground, on the place where the furnace is to 
 be erefted. This muft be large enough, to ad*- 
 mit the laying the foundation of the furnace in 
 it ; and about eight inches deep ; that the bars 
 of the fireplace may lie on a level with the 
 ground \ the afh-hole being below it. 
 
 The reafon, for making this part of the fur- 
 nace below the ground, is,- to prevent the other 
 parts from rifing too high ; which is a great in- 
 convenience to the operator, with refped: to the 
 fand-pot, when he has occafion to put a charged 
 retort into the pot ; in doing which, he greatly 
 Jofes his command of it, if the pot be placed high ; 
 
 Q > an4 
 
■i« INTRODUCTION. 
 
 and alfo with regard to the fand-bath ; which, 
 being of courfe coniiderably higher than the 
 fand-pot, requires, in this cafe, that the opera- 
 tor fhould have fomething to ftand upon, in 
 order to manage the full retorts put into it : 
 an expedient to be avoided wherever it may. 
 
 The ground plan or foundation of the fur- 
 nace muft be laid in this hole, of dimenfions 
 fuitable to the diameter, as computed by the 
 rules above given ; and carried up of folid brick- 
 work of a cylindrical form. But an area muft 
 be left for the aih-hole ; which muft be pro- 
 portioned by laying the bars, fixed in their pro- 
 per fituation by means of the crofsbars above 
 directed, on the ground, in the center of the 
 cylinder ; and drawing two lines, begun at the 
 furtheft crofsbar, and continued, parallel to the 
 two outermoft bars, at the diftance of a quarter 
 of an inch from them, to the front of the cy- 
 linder. The fpace, fo defcribed, muft be left 
 hollow ; the brickwork being carried up on the 
 three fides of it. This may be done with com- 
 mon bricks and coal-afh mortar : but they 
 muft be laid folid, that the whole mafs may 
 not fhrink, when the mortar fhall be fubjefted 
 to a great heat. The cylinder of brickwork be- 
 ing thus raifed about eight inches high, the 
 bars of the fireplace muft be laid over the in- 
 nermoft part of the vacuity left for the afh- 
 hole ; and the door, with its frame, muft be 
 alfo placed in the front of the bars ; (though 
 they will not be, in this manner of conftrufti- 
 on, on a level with the exterior furface or front 
 
 of 
 
INTRODUCTION. 19 
 
 of the furnace;) and the brickwork muft be 
 again carried up fix inches, in the fame man- 
 ner as before : only it muft be made to take 
 proper hold, both of the crofsbars of the fire- 
 place, and frame of the door. Eut the courfes 
 next the fire muft *be of Windfor brick, and 
 laid with Windfor loom, or Sturbridge clay y 
 and, if the heat be intended to be very violent* 
 the joints next the fire fhould be pointed with 
 the fire lute hereafter mentioned. 
 
 When the fabrick is raifed to this height, an 
 iron plate of a fufficient ftrength, or two broad 
 bars, fhould be laid over the void part, or open- 
 ing, leading to the door and afh~hole; that the 
 brickwork may be carried intirely round above : 
 and the cylinder muft be continued as before j 
 only the cavity muft be made Hoping from the 
 upper part of the area defjgned for the fire-* 
 place, and inlarged in fuch manner; that, in 
 railing the furnace eight inches higher, the di~ 
 ameter of the cavity fhall be fix inches more 
 than the diameter of the fand-pot : which fix: 
 inches is to allow for the three inches diftance 
 betwixt the pot and the fides of the furnace, 
 that will here begin to be parallel. The frame 
 for forming the hole, for feeding the fire as 
 before defcribed, fhould be fixed in the laft 
 courfe of bricks, which make this flope : the 
 moft convenient fituation for which is ; the 
 front of the furnace, diredlly over the opening 
 for the door and afh-hole. 
 
 From this height, a cylinder muft be car- 
 ried up, parallel to the fides of the fand-pot at 
 
 C 2 three 
 
2o INTRODUCTION. 
 
 three inches diftance, till within fomething lefs 
 than a third of the top of the fand-pot j fup- 
 pofing the bottom to be on a level with the 
 foot of this cylinder : and then the hollow muft 
 Hope gradually inwards, till it be no wider 
 than juft to fuffer the fand-pot to be let down 
 into it 
 
 In the brickwork of this upper flope, muft 
 be left a cavity, for conveying the fmoke and 
 flame under the plate of the fand-bath. It 
 muft be in the center of that part, where the 
 fabrickof the fand-bath joins the furnace; and 
 fhould be four inches and a half, or five inches, 
 in length -, and about two inches in height. 
 
 The whole of this part of the furnace may 
 be common brick ; but the mortar fhould be of 
 Windfor loom. On the top of the brickwork, 
 raifed to this ftate, muft be laid the iron ring 
 or rim (before mentioned), defignedto hold the 
 fand-pot : it fhould be laid in with fire lute, 
 and well pointed, with the fame, at the joint it 
 makes with the bricks within the hollow of 
 the furnace. A proper plate fhould alfo be laid 
 over the cavity, left for carrying the fmoke and 
 flame under the fand-bath. 
 
 When thefe parts of the furnace arefo dried, 
 as to hold well together, the pot fhould be let 
 down into the ring ; where it muft hang by 
 its margin or turned edge ; and another courfe 
 of bricks muft then be raifed, in a continued 
 line with the fides of the fand-pot ; that part of 
 them, which touches the pot, being laid in fire 
 lute 5 and the other parts in coal-afh mortar. 
 1 In 
 
INTRODUCTION. 21 
 
 In this courfe a Hope mull be made, on the fide 
 oppofite to the fand-bath, or front, which ever 
 lhall appear moft convenient, for the neck of the 
 retorts to bend Efficiently downwards when 
 placed in the pot. The whole of the furnace 
 which relates to the fand-pot being fo com- 
 pleted, the fand-bath muft be thus added. 
 
 A ground plan or foundation muft firft be 
 laid 5 which need not, in this cafe, be funk be- 
 low the level of the flooring of the 'place : it 
 muft be proportioned according to the fize of 
 the plate intended to be ufed. The length 
 muft be that of the plate, with the addition of 
 the breadth of two bricks : the breadth muft 
 be that of the plate, and the length of two 
 bricks. It muft be formed by building, as it 
 were, four walls, that mark out this proportion; 
 the area within them being, for the prefent, left 
 hollow. This may be done with common 
 bricks, and common mortar : only great care 
 fhould be taken, the bricks may reft every 
 where on each other, fo that there may be no 
 fettling when the work fhall be dry. 
 
 In adjufting the fite of the area marked out 
 for this foundation, it muft be obferved, to 
 take, about three inches depth of the fide of 
 the furnace round the fand-pot, into the end 
 of the area next it. This projection, of the one 
 part of the furnace into the other, is neceffary, 
 in order to the bringing the end of the plate 
 clofe to the flew, that is to convey the flame 
 and fmoke into the cavity under it, without be- 
 ing obliged to lengthen the paflage; which 
 
 C 3 muft 
 
22 INTRODUCTION, 
 
 muft otherwise be the cafe > if the whole fquare 
 of the brickwork of the fand-bath was built, in 
 a diftin<ft area, -on the outfide the round build- 
 ing for the fand-pQt. 
 
 The four walls, as above direded, may be 
 carried up ; till they rife, within the thicknefs of 
 a brick, to the level of the lower part of the flew 
 for conveying the fmoke and flame : and the 
 hollow, formed by this fquare of walls, may be 
 then filled up with broken, or whole, bricks, 
 laid firmly on each other ; the joints or inter- 
 faces, betwixt them, being alfo filled up with 
 dry afhes. 
 
 A flooring of bricks fhould then be made over 
 this fquare body : they muft be laid in coal-afh 
 mortar on the under fide ; and the joints on 
 the upper fide pointed with Windfor loom. 
 
 On this flooring, another area muft be form- 
 ed by laying rows of bricks at fuch diftance, 
 that the plate may reft on them one inch on 
 each fide. They muft be laid crofsways to each 
 other, and for the ends next the plate Windfor 
 loom fhould be ufed ; and for the other part 
 coal-alh mortar : the plate muft be then laid on 
 them, and fet with fire lute. 
 
 The openings at the lower ends, into the 
 cavity under the plate, muft be likewife clofed 
 up by bricks laid breadth way ; the fame cauti- 
 on being ufed, as before, for the fides, with re- 
 fped: to the kind of mortar : but the opening 
 pf the flew, for conveying the fmoke and flame 
 under the plate, muft be preferved 5 as like- 
 wife another opening at the other end for the 
 
 paflage 
 
INTRODUCTION. 23 
 
 paflage of the fmoke into the chimney ; over 
 which opening, a plate, or two broad bars, 
 muft be laid, to fupport the brickwork of the 
 fide over it. 
 
 A courfe of bricks, laid breadthways, muft 
 then be raifed, ciofe to the edge of the plate, 
 intirely round it : the joints, where they meet 
 the plate, being made good with fire lute ; but 
 the reft with coal-afh mortar: and, over this 
 courfe, as many others may be laid (but with 
 coal-afh mortar only), as will raife the fides of 
 the bath to a due height ; which muft be re- 
 gulated by the fize of the retorts to be ufed in 
 it. 
 
 A chimney muft then be built, from the 
 ground, clofe to the vent or flew for carrying 
 off the fmoke : or, if there be any other chim- 
 ney within reach, a longer flew may be made, 
 for the communication of the furnace with it; 
 and the erecting a new chimney avoided. 
 
 When the whole is of a proper drynefs, the 
 part of the furnace, belonging to the fand-bath ; 
 may be plaftered over with good lime mortar : 
 but the dung of horfes, which have eaten hay, 
 fhould be mixed with it inftead of hair, which 
 is apt to burn in the heat it is liable to fuftain 
 here. The fand-bath muft be alfo plaftered : 
 but mortar with hair is better for that purpofe ; 
 as, not being fubjecft there to burn, it will hold 
 the fides of the bath firmer together than any 
 other kind. 
 
 It has been a practice, to put facking over 
 the plaftering of this fort of furnaces, as well 
 
 C 4 as 
 
24 INTRODUCTION. 
 
 as thofe belonging to the houfhold coppers, iii 
 order to prevent the effefts of a falfe draught 
 through any cracks, the heat may produce in 
 the fides of the furnace. But it is very injudi- 
 cious. For, in furnaces of this kind, the lack- 
 ing never fails to burn ; and loon occafions all 
 the pi altering to fall to pieces ; and bring away 
 with it the mortar ; and even, in the cafe of 
 coppers, it burns near the door of the fire- 
 place, and frequently loofens the whole fheet 
 of plafter round the furnace. 
 
 If this kind of furnace be completed, ac-> 
 cording to the directions here given, arid gra- 
 dually dried, it will continue in order, if care- 
 fully ufed, for a long time : and when the 
 fand-pot, which will be the firft part of it, that 
 will fail, fhall become unfit for further fervice, 
 the courfe of bricks above it being removed, it 
 may be taken out of the ring ; and the fire- 
 place, arid other parts of the cavity, being re^- 
 paired, and well pointed, a new one may be 
 put in its place ; and the courfe of bricks above 
 it reftored : and this may perhaps be repeated 
 a third time, before there be occafion, to take 
 down any other part of the furnace. 
 
 Of tie furnace for the fublimation of calomel. 
 
 This operation being, now, moft generally* 
 and indeed bell, performed in mattraffes or 
 rounds of glafs, with fhort narrow necks, the 
 fand-pot fubfervient to it muft be proportiona- 
 bly ihallow; and the depth of the furnace coN 
 
 refpon- 
 
INTRODUCTION. 25 
 
 respondent ; which renders it not commodi- 
 ouily practicable in the common fand-pots ; 
 whofe dimenlions are fuited to retorts and ob- 
 long bodies or cucurbits. On which account, 
 therefore, a peculiar furnace, properly adapted 
 to this intention, is neceffary ; as the fublima- 
 tion of calomel is one of the moft material, 
 and not the leaft profitable, proceffes of the 
 chemical pharmacy. 
 
 The conftrudtion above given, for the fur- 
 nace of the common fand-pots, will ferve 
 equally well for this purpofe likewife : allow- 
 ing for the different fize of this kind of fand- 
 pot - y w r hich muft be regulated by the magni- 
 tude of the mattrafles to be ufed in it. The 
 depth of the pot fhould be two inches more 
 than two thirds of the diameter of the mat- 
 traffes. For they muft be placed two inches 
 above the bottom of the pot ; and immerfed 
 about two thirds of their diameter in the fand. 
 The breadth fhould be five inches more than 
 the whole diameter of the mattrafifes 5 as every 
 part of them fhould ftand two inches and a 
 half from the fides of the pot. The area of 
 the fire-place need not be more than a fquare 
 of fix inches : and the courfe of bricks above 
 the pot muft be wholly omitted : nor is there 
 any occafion, to have the lower part of the 
 furface funk below the level of the ground of 
 the place ; as is required in the former kind. 
 In all other refpe&s, the proceedings, for 
 the eredling this, may be the fame, as has 
 been before directed for the other. 
 
 Of 
 
26 INTRODUCTION. 
 
 Of the furnace for calcination, commonly called 
 the wind furnace. 
 
 This furnace being principally defigned for 
 operations on metals ; as the deflagration of 
 the crocus antimonij of the college, the anti- 
 hedticon Poterij, and fuch others, it need not 
 be bigger than to contain a pretty large cruci- 
 ble ; which a fireplace, whofe area is about 
 eight inches fquare, will very well allow. 
 
 The beft manner of erecting this kind of 
 furnace is as follows. 
 
 Firft prepare a fet of bars, of the proper 
 dimenfions, according to the directions above 
 given ; as alfo a ftrong. iron door, with its 
 frame, of about eight inches fquare : with a 
 plate, or two flat bars of a proper fize to fup- 
 port the brickwork over the afh-hole ; and 
 another ftrong one, for the fame ufe, over the 
 door. 
 
 A foundation or pedeftal of bricks muft 
 then be raifed, about three feet and a half 
 high, and two feet fquare ; which may be done 
 with common bricks and mortar; and need 
 only, indeed, be four walls ; the hollow, formed 
 by which, may be filled up with rubbifh, and 
 floored over with bricks or tiles. 
 
 On this pedeftal, raife three other walls ; 
 one on each fide, and one at the farthermoft 
 end, of the whole brick thicknefs ; forming 
 an area, betwixt them, of the length of fix- 
 teen inches, and of the breadth of eight ; of 
 
 which 
 
INTRODUCTION. 27 
 
 which area, the front will be open from the 
 default of the fourth wall. 
 
 Over this opening in the front, lay the bars, 
 in the center of the brickwork; and place 
 along with them a plate, that will reach from 
 their edge to the front of the fabric, to bear 
 the brickwork which muft lie over that part 
 of the hollow. Then carry up the fides as 
 before, but with four walls inftead of three, 
 to inclofe the area of the fireplace completely 
 with brickwork : taking care, that the firft 
 courfe have good hold of the flat ends of the 
 crofs-bars. 
 
 This part muft rife fix inches above the bars, 
 and then the door and frame muft be fixed ; 
 and the other three fides carried up afc before. 
 When the building is raifed to the height 
 of the door and frame, the ftrong plate muft 
 be laid, to bear the brickwork over it ; and 
 the brickwork muft be then gradually made to 
 converge, till it become a chimney, of which 
 the hollow is fix inches fquare : or it may 
 be turned into a funnel or flew, to communi- 
 cate with the chimney of another furnace, if 
 any be fufficiently near. But, as the wind- 
 furnace demands a very confiderable draught, 
 if the flew from it be made into the chimney, 
 belonging to any other furnace, which may 
 not happen to be at work when there is oc- 
 cafion to ufe this, care muft be taken to ftop 
 the vent of fuch furnace into the chimney, 
 to prevent the falfe draught ; which will other- 
 wife intirely deftroy its eflfefts on the wind^ 
 
 furnace. 
 
a3 INTRODUCTION. 
 
 furnace. This caution ought, indeed, to be 
 always carefully obferved, where one chimney 
 ferves for the ufe of two or more furnaces : 
 otherwife much time and trouble may be 
 thrown away, by the fire proving very un- 
 equal to the occalion. 
 
 The whole of the wind-furnace, from the 
 bars to the top of the door, fhould be built 
 of Windfor bricks, laid in Windfor loom, and 
 pointed on the infide with fire lute. 
 
 Of retorts and receivers. 
 
 Thefe are the moft employed of any glafs 
 utenfils, in the practice of modern phar- 
 macy: having almcft fuperfeded the ufe of 
 all others. Formerly cucurbits, with glafs heads 
 were chofen for many operations 5 and alio- 
 dials were in fome cafes added : but large re- 
 torts, with proportionable receivers, will better 
 anfwer almoft all the fame ends. 
 
 The common form of retorts is not faulty \ 
 provided two kinds of them be had : the one 
 fhort and thick, with very long and large 
 necks ; and the other taller, with fhort necks. 
 The particular ufe of each of thefe kinds, will 
 be pointed out, in fpeaking of the feveral ope- 
 rations, to which they are intended to be fub- 
 fervient. But it will be found veiy advantage- 
 ous, to have a ftock of both forts ready for all 
 occafions 3 and to be prepared to render the 
 necks fhorter, and enlarge their orifices, ac- 
 cording to the defigned ufe. This mull be 
 
 done 
 
INTRODUCTION. 29 
 
 done by iron rings ; whofe diameter muft be 
 correfpondent to the intended thicknefs of the 
 end of the neck. If the ring be applied to 
 the part where thefeparation is to be made, 
 and this heated part be touched with any 
 moifture, the piece behind where the ring has 
 been placed will immediately fall off. 
 
 It is ufual to have this done at the glafs- 
 houfe, before the retorts are lent from thence ; 
 but every good operator fliould fee it per- 
 formed himfelf, in the manner iuitable to the 
 ufe, the retort is to be applied to. For on the 
 adapting properly, the fize, and form, of the 
 retort, to the nature of the operation, the 
 fuccefs in many cafes depends in a greater de- 
 gree, than can be imagined by thofe, who 
 have not had occafion to make accurate ex- 
 periments of this kind. 
 
 Receivers fliould be alfo always had, both 
 with fhort, and long, necks : it is proper in- 
 deed to have them much larger, for moft pur- 
 pofes, than what are generally ufed. A 
 greater quantity of condenfing furface render- 
 ing the operation both more profitable and 
 fafe y as it prevents the forcing of the lute, and 
 the efcape of the vapour; as well as the hazard 
 of burfting the veflels, on the railing the fire 
 too high • if the luted juncture fhould hold 
 good againfl: the force of the expanded vapour ; 
 or the necks of the retort and receiver 
 fhould fit fo exadly as to admit no paflage 
 for it. 
 
 Of 
 
30 INTRODUCTION, 
 
 Of cucurbits or glafs bodies for fublimatioiu 
 
 Though the moft general ufe of retorts has 
 greatly excluded that of this kind of veffel ; 
 yet there are fome proceflfes, which require, 
 that they fhould be retained ; as in the inftance 
 of mercury fublimate, cinnabar of antimony, 
 ens veneris, and others. The common form 
 is good y but fhould be varied into two kinds, 
 the one thick and fpheroidal, or of a true oval 
 form ; the other long and greatly tapering. 
 The different ufe of each kind will be 
 fhewn, in treating of the refpe&ive operations, 
 where they are to be ufed. A fort, with the 
 bottom almoft flat, of a fmall height propor- 
 tionable to the breadth, and tapering fo as to 
 form a narrow neck at the top, fhould be alio 
 had, where camphire is to be purified. 
 
 Of tritoriums, or feparating funnels. 
 
 The common figure and fize of thefe veflels 
 will anfwer the purpofe, where only fmall 
 quantities of the fluids to be feparated are in 
 queftion : but where difpatch is wanted, and 
 the quantity large, they fail to perform what 
 is wanted, in any efficacious manner. The 
 greateft occafion for this kind of inftrument to 
 be rendered effe&ual, as to confiderable quan- 
 tities of fluids, Is with refpeft to the feparating 
 the oil from the fpirit of hartfhorn y as well 
 after the firft diftillation from the materials, as 
 
 the 
 
INTRODUCTION. 31 
 
 the fubfequent rectifications. It is there beft 
 done by very large glafs funnels ; and a tin or 
 pewter veflel, whofe ftrufture we fhall here 
 defcribe ; but refer, both for the ufe of it, 
 and the funnels, to the procefs for preparing 
 this medicine. 
 
 The tin or pewter veflel may be of a cylin- 
 drical fhape, of a foot diameter, and four or 
 five feet in length. It muft be made entire, 
 both at the top and bottom : but muft have a 
 fhort tube, at the top, for receiving a large tin 
 funnel, by means of which, it may be filled ; 
 and two other fmaller tubes, in the body -, the 
 one of which muft be about a foot from the top ; 
 and of the thicknefs of the little finger : the o- 
 ther muft be about fix inches from the bottom ; 
 and of the thicknefs of a fwan's quill. Thefe 
 laft tubes, may be about three inches long ; 
 and muft have wooden ftoppers wound about 
 with linnen, or thread, to make them fit; 
 but the firft tube need not be more than 
 inch long ; and may be flopped with a cork. 
 
 Of filters. 
 
 The flannel bags, employed for this pur- 
 pofe, do the office very well, where no greater 
 purification is required, than the ftraining thro* 
 flannel can efFedt : but, where a greater clear- 
 nefs is neceflary, paper may be ufed. The 
 fmall glafs funnels, generally applied to this 
 end, are neither capable, with refped: to dif- 
 patch or quantity, of anfwering well their pur- 
 1 pofe : 
 
3* INTRODUCTION. 
 
 pofe : for which reafon, this operation is fre~ 
 quently omitted, where the quantity of fluid 
 is great, in cafes, where it might be praftifed 
 with great advantage and convenience, were 
 better methods underftood. The kind of 
 filters, I would recommend, intirely remove 
 all difficulties in the practice of this neceffary 
 means of purification ; and may be applied, 
 as well to the greateft, as the fmalieft quanti- 
 ties. It is an earthen cullender made of a 
 fize proportionate to the bufinefs intended to 
 be performed by it; and fuller of holes, which 
 ought to be alfo of a larger bore, than in the 
 fort intended for houfhold purpofes. The 
 cullender of the largeft fize muft not however 
 exceed, what a fheet of filtering paper will 
 well cover : for any greater magnitude than 
 that would become ufelefs. With thefe, muft 
 be had, alfo, a glafs funnel, whofe mouth is 
 broader than the cullender; and a ftand of 
 wood, by which the cullender may be fup- 
 ported over the funnel. Where this kind of 
 filter is not ufed, in the intention of purifying 
 any liquid body, but for feparating a fediment 
 or precipitated powder from fome fuperfluous 
 fluid, a linnen cloth, of the fize of the paper, 
 muft be alfo procured. 
 
 By this apparatus, all the ends of fil- 
 tering may be anfwered with great eafe and 
 expedition. Very large glafs funnels will 
 next fuit this purpofe beft ; provided the 
 paper be fupported, in the hollow of the 
 funnel, with a little cotton lightly thruft 
 
 into 
 
INTRODUCTION. 33 
 
 into the hollow: but this method is much 
 more precarious, as well as flower, than the 
 other : the paper, if not good, or ufed with 
 fluids of a relaxing quality, being very fub- 
 ject to break during the operation ; which 
 fruftrates the whole already done. 
 
 Of *vef[ehfor the chryftallization of falts. 
 
 Very large glafs receivers, containing eigHt 
 or ten gallons, fhould be provided, and fixed 
 in ftraw, in baflcets, fo firmly, by means of 
 fticks or cords pafled through their fides, that 
 the glafs and bafket may be reverfed together. 
 Large earthen cullenders fhould be likewife 
 procured with narrow bottoms for receiving 
 the falts when taken out. This apparatus will 
 very well ferve the purpofe, for common ela- 
 boratories : but, where the chryftallizing glau- 
 bers, or other falts is made a particular manu- 
 facture, the following will difpatch very great 
 quantities, with much lefs trouble. 
 
 A leaden boiler muft be placed over a very 
 gentle furnace ; at a due diftance, from this, 
 muft be placed a leaden ciftern ; for the forma- 
 tion of the chryftals, proper fized baflcets muft 
 be provided, to place over this ciftern, by means 
 of a frame laid crofs it, for receiving the chry- 
 ftals when taken out of the ciftern. A large 
 flat frame of baiket- work, with a rim of the 
 fame, round the edge, rifing two or three 
 inches, to prevent the falts from falling off, 
 muft likewife be made, for drying the falts. 
 
 D For 
 
 
34 INTRODUCTION. 
 
 For the chryftallizing tartar, or making 
 cremor tartaris, the following apparatus may 
 beufed, with great advantage. A large leaden 
 boiler mull: be fet over a gentle furnace ; to this 
 muft be joined two cylinders of lead, by means 
 of two pipes, which muft have a ftop-cock to 
 cut off the communication when neceflary. 
 
 Of the apparatus for levigating tejlaceous, and 
 other hard y bodies, where the quantity to be 
 prepared is great. 
 
 The common implements ufed for this pur- 
 pofe, (viz.) the mortar, and levigating-ftone 
 and muller, are very well adapted to the end. 
 But fince the late attempts, made by particular 
 perfons, to gain advantages by the preparation 
 of the medicines of great consumption, at very 
 low rates, by more expedite means, a method 
 has been pra&ifed of performing this opera- 
 tion, with much lefs labour, and confequently 
 greater profit, than by the ufual way. 
 
 This has been done by the introduction of 
 the horfe-mill and roller; which have been 
 applied to this purpofe, in the fame manner, 
 as it was before by the fugar refiners, and 
 manufacturers of fnufF ; and at the fame time 
 that the machine grinds the materials, it alfo 
 works the fieves for fearcing the powder. 
 
 Thofe, who would difpatch large quan- 
 tities, will find great favings in the ufe of this 
 method : but I think it needlefs to give a 
 defcription, here, of the conftruftion of fuch 
 
INTRODUCTION. 35 
 
 a mill ; as they, who make it their proper 
 bufinefs to ereft them, and muft of courfe be 
 employed for that purpofe, do not want direc- 
 tions for the manner of making that part, 
 which properly belongs to the mill, in the 
 ufual way : and will eafily find out an expe- 
 dient manner of adding the parts requifite for 
 working the fieves, when they are informed of 
 the ufe of them. 
 
 An improved apparatus ', for the more commodious 
 and advantageous dijlillation of volatile fpirits 
 from bart/hom, bones, or any other proper animal 
 fubflance, by the ufe of a worm as a refrigeratory. 
 
 A large iron-pot muft be firft provided of the 
 following form. The body of the pot muft be 
 of a cylindrical figure, with a concave bottom : 
 and converging at the top, fo as to make a kind 
 of wide conical neck. Into this neck, muft be 
 inferted a tubulous arm ; which is to ferve, 
 inftead of the head ufed in common ftills, to 
 convey the vapour into the worm or refrigera- 
 tory. The height, from the bottom of the 
 pot to the beginning of the converging part 
 or neck, may be four feet \ and the diameter 
 two and a half. The length of the converg- 
 ing part or neck may be two feet ; and the 
 diameter of it, at its joining with the pot, at 
 the top or mouth of it one foot. The 
 length of the arm may be one foot eight 
 inches ; and the diameter of it, at its joining 
 with the pot, four inches; and diminifhing, gra- 
 
 D 2 dually 
 
36 INTRODUCTION. 
 
 dually, to two inches and a half, at the other end. 
 This arm muft Hope downwards, in fuch man- 
 ner, that any fluid, which ihall be condenfed in 
 it, will run out at the end : that is to fay, the 
 axis of the cone, formed by this arm, muft 
 decline two inches from the horizontal plane. 
 The edge of the pot, at the top of the neck, 
 muft be dilated*, and turned outwards : and a 
 groove muft be made in it, to receive a flat 
 cover of lead. In the body of the pot, muft 
 be inferted, three tronions, of about fix inches 
 length: they muft be ftrong enough to bear 
 the weight of the pot, when it is hung in the 
 brickwork by their means. They fhould be 
 placed, at equal diftances, a little below that 
 part of the cylindrical body where the neck 
 begins to form itfelf. The groove, in the neck, 
 fhould be filled with a folid piece of lead ex- 
 actly fitted and cemented to it : in this, ano- 
 ther groove muft be cut, to receive a leaden 
 cover adapted to it, fo as not to make a per- 
 fectly clofe joint ; which may be eafily done, 
 by beating the cover, after it is placed in the 
 groove, till it fit in every part. The cover muft 
 be made of lead, about a quarter of an inch 
 in thicknefs ; and a bow handle muft be fixed 
 in the middle of it. 
 
 A door and frame, bars for the fireplace, 
 frame and ftopper for the hole for feeding the 
 fire, &c. muft be provided, in the fame man- 
 ner as for the furnace for the fand-pot. 
 
 The foundation of the furnace muft be alfo 
 laid as for that of the fand-pot : only it fhould 
 
 not 
 
INTRODUCTION. 37 
 
 not be funk, as in that cafe, below the level of 
 the ground. For the bars of the fireplace may 
 well be admitted to be eight or nine inches a- 
 bove it, without danger of raifing the other 
 parts of the fabric too high. 
 
 The dimenfions of the ground plan muft be 
 thus fettled. Take the diameter of the pot; 
 and add to it fix inches, and the length of two 
 bricks. 
 
 The proceedings in the reft of the parts muft 
 be the fame, as were before directed for the 
 fand-pot : the fame proportion alfo being ob- 
 ferved betwixt the bottom of the pot, and fur- 
 face of the fire : and likewife between the 
 fides of it, and thofe of the furnace. The pot 
 muft, however, after the fireplace, and Hope 
 above it, are built, be fixed in its intended fitua- 
 tion, with the help of props, by which it muft 
 be there fupported, till the fides of the fur- 
 nace be raifed high enough, to take the troni- 
 ons, and bear the pot. The furnace may be 
 carried up round the pot, in a parallel form to 
 it, at the diftance of three inches : for, as the 
 pot is hung by means of the tronions, there is 
 no occafion for any Hope, at the extremity of 
 the brickwork, to make it fupport the pot ; 
 but the cavity may be clofed in, by bricks laid 
 crofs, from the fide of the furnace to the pot, 
 juft above where the cylinder ends. Thefe 
 bricks fhould be fet, where thev touch the 
 pot, with good fire-lute; and fo floped at 
 their end, as to fait the figure of the pot ; 
 and lie as clofe to it as poffible. 
 
 D 3 A 
 
38 INTRODUCTION. 
 
 A hole muft be left in the fide, juft undef 
 the bricks that clofe in the cavity, for the com- 
 munication with the chimney, which muft be 
 managed, as in the former furnace ; as muft 
 likewife the plaftering, &c. 
 
 A worm, and proper tub, muft be then pre- 
 pared, of the fame form with thofe commonly 
 ufed y but differing greatly in dimenfions. For 
 the pipe (hould be two inches and a half in 
 diameter, and twelve feet in length. At its 
 exit from the tub, a fmaller pipe, of about 
 three quarters of an inch in diameter, muft be 
 joined to it, in fuch manner, that the bore of 
 this fmall tube, may be in the depending part 
 of the bore of the large one, that the paffage 
 may not be obftru&ed by the joint. This 
 lefier pipe fhould be about a foot long ; and 
 muft be fo turned downwards, that it may go 
 into the neck of the receiver ; or, at other 
 times, have its orifice flopped by a cork. In 
 the higheft part of the w r orm, within the tub, 
 muft be likewife inferted another fbort pipe, 
 of half an inch diameter, and fix inches length ; 
 in order to receive a funnel, for filling the worm 
 occafionally with water : this pipe may have 
 a leaden ftopper fitted to it ; as it muft be al- 
 ways clofed, when there is no necefiity to ufe 
 it. The upper end of the large pipe, which 
 forms the worm, muft pafs through the fides 
 of the tub, as well as the lower ; and muft be 
 joined to the arm of the pot, by means of fheet 
 lead ; which muft embrace the arm, and the 
 fides being properly floped ajid foldered toge- 
 ther, 
 
INTRODUCTION. 39 
 
 ther, it muft be brought to form a pipe, of 
 nearly the fame bore with that of the worm, 
 to which alfo it muft be foldered ; care being 
 taken, that the current be preferved here as 
 well as in the other end. The whole of the 
 worm may be of lead, as it is much cheaper 
 than pewter, and it will not be fo corroded by the 
 diftilled matter as to occafion any inconvenience. 
 
 The tub need not be of greater dimenfions, 
 than are neceflary, to fuit the figure of the 
 worm : and to contain about fix inches height 
 of water over it. 
 
 Two large receivers fhould be likewife pro- 
 vided, for containing the diftilled matter, as it 
 flows from the pipe of the worm. They 
 fhould be made with narrow necks, to receive 
 the end of the pipe affixed to the worm ; as 
 alfo with a flattifh bottom, and ftrong, in the 
 bottle fafhion, as they will ftand with their 
 necks upwards. The reafon for directing du- 
 plicates of them is, that the one may be ready 
 to be put to the worm, when the other is taken 
 away to be emptied ; as they will be feveral 
 times filled during one operation. 
 
 A tin pipe, of about half an inch diameter, 
 and of fufficient length to pafs, from the neck 
 of the receiver, to the afh-hole of the furnace, 
 muft alfo be provided. To the end of this 
 pipe, another piece of the fame bore, about 
 three inches in length, muft be foldered, at an 
 angle fomething greater than a right one ; being 
 firft reduced to a flattifh form, except where it 
 joins to the long pipe, fo that, when the long pipe 
 
 D4 is 
 
4 o INTRODUCTION. 
 
 is laid from the afh-hole into the receiver, this 
 may go into the neck of it, along with the end 
 of the pipe fixed to the worm ; and the remain- 
 ing part of the orifice of the neck of the re- 
 ceiver, being luted with ftiflf clay, may convey, 
 any fumes or vapour, which may remain un- 
 condenfed in the receiver, under the bars of 
 the fire : through which being carried by the 
 draught of air, the elaboratory will confe- 
 quently be freed, in a great degree, from the 
 powerful and offenfive fmell which attends 
 this operation* 
 
 A kind of iron ladle, with a wooden handle, 
 that will reach to the bottom of the iron pot, 
 and to which the ladle fhould be fixed almoft 
 horizontally, muft be made ; for emptying the 
 pot of the remaining part of the matter after the 
 diftill&tion. The fize of this muft be deter- 
 mined by the neck of the pot ] to which it 
 muft be fo proportioned, as to pafs in and out 
 freely. 
 
 A funnel of tin muft be alfo provided, to fill 
 the worm with water, whenever there {hall 
 be occafion. 
 
 A pewter alembic >f or the dijlillation of the vola- 
 tile fpirit offal ammoniacum, and the fpiritus 
 volatilis hromaticus^ 
 
 This • alembic muft be made of good pew- 
 ter : its body may be either of a cylindrical 
 figure, or a long fquare, fuited to the form of 
 the fapd-bath where it is to be ufed 5 its neck 
 
 fhould 
 
INTRODUCTION. 41 
 
 fhould be about fix inches high, and five in 
 diameter, with a proper groove, to admit a 
 cover to be put into it, fo as to make a clofe joint 
 with as little lute as poflible. From this neck, 
 muft go two hollow arms, like that of the 
 hartfhorn pot before mentioned. They may 
 be of the diameter of two inches, and about 
 eighteen inches long, or as may be moft con- 
 venient, to admit a receiver to be fixed to them, 
 according to the fituation where they are to be 
 ufed. They muft Hope downwards, in fuch 
 manner, that the fluid, which is collected, in 
 them, from the vapour, may flow into the 
 receiver. If the fand-bath, or pot, where they 
 are to be ufed, ftand clear of any wall, the 
 arms may be fixed oppofite to each other : but 
 if the fand-bath be placed againft a wall, fo 
 that receivers can be put on one fide only, the 
 arms may be both on that fide of the alembic ; 
 but fixed to form fuch an angle, as may give 
 room for the receivers to be put to them : and 
 their length muft be fo proportioned, as to free 
 the receivers from the fide of the fand-bath. 
 
 Receivers muft alfo be made, with necks 
 fuited to thefe arms : and they fhould be pro- 
 cured of as large a fize as they can be made, 
 preferving a proper ftrength. 
 
 Of the apparatus^ for the diftillation of the oil 
 of turpentine. 
 
 The form of the furnace, and iron pot, a- 
 bove defcribed, for the diftillation of the fpirit 
 
 of 
 
42 INTRODUCTION. 
 
 of hartfhorn, will equally well ferve for this 
 purpofe : but the cover of the pot ihould have 
 a fhort tube in it, by which the pot may be 
 occafionally fupplied with water, during the 
 diftillation : and this tube fhould have a leaden 
 {topper fitted to it, by which it may be clofed 
 at all other times. The pipe of the worm, 
 provided for this purpofe, need not, however, 
 be of the widenefs necelTary for volatile fpi- 
 rits ; but may be of the common form, and 
 dimensions, ufed in other cafes. Befides a 
 ladle of the fame kind with that dire&ed, for 
 taking out the remaining materials after diftil- 
 lation of volatile fpirits, another inftrument 
 muft be had, for cutting, or dividing, the re- 
 maining colophony, whether rofin, or pitch, 
 after the diftillation of the fpirit of turpentine, 
 in order to its being fo divided, as to pafs the 
 narrow part of the neck : it rnuft be formed 
 of a flat piece of iron, half round, with a mo- 
 derately ftiarp edge, fixed into a wooden han- 
 dle, of a due length, with the round end down- 
 wards : the breadth of the iron, and the 
 length of the handle, may be regulated, by 
 the widenefs of the neck, and the depth of 
 the pot. 
 
 An alembic for the diftillation of quickfiher. 
 
 The common inftruments, directed in the 
 books of chemiftry, or ufed in the elaboratories 
 for the preparation of medicine, for the per- 
 forming this operation, are very defective : be- 
 i inrg 
 
INTRODUCTION. 43 
 
 ing either retorts, or other glafs veflels, which 
 are very liable to break, as well as the receivers 
 ufed with them as refrigeratories : but the re- 
 finers, and others, who have more frequent 
 occafions to re-purify mercury, have introduced 
 an inftrument, which anfwers this end with 
 very little trouble or hazard. It is a kind of 
 deepilh pan of iron, with a cover, of the fame 
 metal, or copper, foldered on to it ; in which 
 cover muft be a fhort tube, for the pouring in 
 the mercury, and taking out the recrement, 
 or caput mortuum, if there fhold be any. 
 
 This tube muft have a ftopper, capable of 
 being fo fcrewed into it, as to render the joint, 
 impervious to the vapour of the quickfilver. 
 Into this pan, at the upper part of one fide, 
 muft be foldered, like wife, a gun barrel, ftop- 
 ing downwards, in order to condenfe the va- 
 pour of the quickfilver when it rifes into it. 
 The end of this barrel muft be fo bent down- 
 wards, that, when the pan is placed on a com- 
 mon fire, it may be immerfed in a veffel of 
 water placed properly for that purpofe. 
 
 An alembic for the diftillation of vinegar. 
 
 This alembic fliould be made of the fame 
 fubftance as the ftone-ware manufactured at 
 Vaux-Hall. It may be round, or made, both 
 in figure and magnitude, as may beft fuit the 
 form of the fand-bath, where it is to be ufed. 
 The neck muft be fhort, and wide enough to 
 admit the lower part of the head to pafs into 
 
 it. 
 
44 INTRODUCTION. 
 
 it. It muft have a head, made of the fame fub- 
 ftance as the body, and formed as the heads, 
 made of the fame earth, ufed for the pots, in- 
 tended for the diftillation of aqua fortis : ex- 
 cept as to the fize, which in this cafe fhould be 
 no more than is neceflary, to admit of two arms 
 proper being joined to it. Thefe arms muft be 
 of two inches diameter, at the extremity ; but 
 larger where they join the pot. Their length, 
 and manner of being fet on the head, muft be 
 regulated, by the place where the alembic is 
 to be ufed, according to the diredions before 
 given, with refpeft to the alembic for the diftil- 
 lation of volatile fpirits. 
 
 The receivers fhould be moderately large : 
 and their necks fuited to the arms of the alem- 
 bic head ; to which they are to be joined. 
 
 Apparatus , for the making oil of vitriol from 
 fulphiir. 
 
 The principal utenfils, in this work, are 
 glafs globes ; which muft be made as large as 
 pofllble, and, according to the late improve- 
 ment in the blowing them, may be of very 
 great magnitude. The globes, having their 
 necks cu% by a proper ring, to a due widenefs, 
 which muft be regulated by the magnitude of 
 the ftopper below defcribed, muft be fixed in 
 a proper frame, with their necks pointing ho- 
 rizontally : but they muft be fo hung, in this 
 frame, that, on occafion, they may be fo 
 
 turned, 
 
INTRODUCTION. 45 
 
 turned, as to difcharge any fluid, they contain, 
 through their neck. 
 
 The frame for fupporting the globes may be 
 of a fquare figure, made of wood, and of a 
 moderate ftrength. The bottom muft be open, 
 fo that fo much of the globe may pafs through, 
 to reft upon the fand, as may be neceflary to 
 heat a gallon of water contained in it. This 
 bottom muft be fixed, with hinges, on the 
 front fide, and reft loofe on the oppofite, on a 
 proper fupport made in the frame 5 fo that, by 
 means of this conftruftion, the back part of 
 the globe may be raifed, by lifting up the back 
 part of the bottom ; and the neck made to 
 decline fo low, that any fluid contents may run 
 out. 
 
 Spoon ftoppers muft be fitted to thefe necks, 
 made of the fame red earth, which is ufed for 
 long necks. The part, that goes into the 
 body of the globe, may be five inches long, 
 and two and a half broad, in the form of a 
 long deep fpoon. The part, which makes the 
 joint of the neck, muft be round, and of a 
 diameter fomething greater than the breadth 
 of the fpoon part ; fo that, when the fpoon 
 part is introduced within the cavity of the 
 globe, this part may fill up the orifice of 
 the neck, and prevent any efcape of vapour 
 through it. 
 
 Furnaces, with fand-pots, muft be likewife 
 provided, for the dephlegmating the oil, 
 after it is obtained in the globes. They may 
 be conftrufted in the manner before direded 
 
 for 
 
46 INTRODUCTION. 
 
 for fand-pots p. 16. and a fhallow fand-bath 
 muft be likewife built, which may be made 
 alfb according to the directions given before : 
 except, that the fides of the bath need not be 
 raifed more than fix inches : becaufe the globes 
 are only to reft upon the fand. 
 
 A furnace, with a fand-pot, may be placed 
 at each end of the fand-bath : and a flew, in 
 that cafe, may pafs to the chimney, from about 
 the middle : or, if the fand-bath can be made 
 very long, more furnaces, with pots, may be 
 conjoined to it, at the fide \ fo as to fupply the 
 heat wanted. In large works, the adjufting 
 the furnaces properly to the number of globes, 
 which are required to be heated, is a point of 
 great confequence \ but cannot be regulated 
 otherwife than by occafional difcretion. 
 
 Retorts muft alfo be provided, for the de- 
 phlegmation. They fhould have large round 
 bodies, with as low necks as poflible : and the 
 fand-pots fhould be adapted to their figure, 
 by their being proportionably fhallow, and 
 wide. The receivers fhould be of moderate 
 magnitude •> but blown ftrong, to prevent the 
 accidents, which are liable to happen, on tak- 
 ing them away from the retorts and emptying 
 them of their contents. 
 
 In the greateft work, which has been hi- 
 therto erefted, the powdering the materials 
 was performed with mortars and peftles : but 
 it would be much more advantageous, in any 
 large work, to employ a horfe-mill, with a 
 
 ' rolling- 
 
INTRODUCTION. 47 
 
 rolling-ftone, fuch as is ufed by the fugar 
 bakers, &c. 
 
 Apparatus for the diftillation of aquafortis. 
 
 A large iron cylindrical pot muft be firft provid- 
 ed. It maybe three feet, or more, in height, and 
 two feet in diameter. It muft have a proper rim, at 
 the top, with a groove, to receive the head, and 
 admit of a due thicknefs of lute's lying alfo in 
 the groove round it. The common figure and 
 proportion of pots, of this kind, now made, is 
 faulty \ they being of a conical form ; by which 
 means, their contents in the part moft expofed 
 to the heat, are leflened, without any advan- 
 tage to compenfate for it : and they are alfo 
 made too broad, in proportion to their height, 
 from whence a considerable part of the effedt 
 of the fire is loft. 
 
 For this pot, a head, with two arms, muft 
 be procured ; of the form, in which they are 
 at prefent made for this purpofe : the dimen- 
 sions muft be regulated by thofe of the pot, 
 as it muft be adapted in the making, by means 
 of a proper meafure given to the w T orkman, fo 
 to the fize of the pot, that it may lie within 
 the groove ; leaving room for lute to be put 
 round it. 
 
 Receivers muft be alfo provided, with necks 
 proportioned to the arms of the head, which 
 they are to receive : they fhould be procured 
 of the largeft fize, and greateft ftrength pof- 
 fible. 
 
 Improved 
 
48 INTRODUCTION. 
 
 Improved apparatus^ for making the fpirit of 
 fulphur by the bell. 
 
 A large retort muft be firft provided : in 
 whofe bottom, a large hole muft be made : a 
 glafs mortar muft be alfo procured, with a 
 concave glafs plate to cover it ; in the middle 
 of which plate, alfo, muft be a hole ; fo that 
 any fluid, which fhall fall into it, may run 
 into the mortar. To thefe, muft be added 
 one of the common glafles, made, in form 
 of a fedtion of a cone, for drinking wa- 
 ter ; which is to ferve as a ftand for a fmall 
 earthen difti, for containing the fulphur. This 
 difh muft be of fuch magnitude, as not to fill up 
 the hole of the receiver ; but, when placed juft 
 within it, may fuffer the air to have accefs, and 
 to pafs, on every fide, round the fulphur. To 
 the neck of the retort, which fhould be long, 
 and cut to a wide orifice, a large receiver muft 
 be fitted ; into which, when blown, muft be 
 inferted a large tube, as wide and tall as pofli- 
 ble ; which tube muft ftand perpendicularly 
 upwards, when the receiver is fixed to the 
 neck of the retort. 
 
 This apparatus will colled: much more fpirit 
 than the bells, commonly ufed ; and may be 
 fo managed, that the fumes maybe carried off, 
 by means of the tubulated receiver, in fuch 
 manner, as to prevent, in a great degree, the 
 annoying the operator, in that difagreeable, 
 
 and 
 
INTRODUCTION, 49 
 
 and indeed detrimental manner, which at- 
 tends the other method. 
 
 An improved form, for a glafs veflel, to be ufed 
 for the preparation of the mercurius-ealcenar 
 tuSy or precipitate per fe. 
 
 The moil: commodious figure of a glafs, for 
 this purpofe, is fuch, as gives the largeft fur- 
 face to mercury contained in it, admits the air 
 moft freely, and, at the fame time, excludes 
 the duft ; which, in this tedious operation, is 
 apt otherwife to be colle&ed. In the follow- 
 ing thefe feveral intentions are perfued. 
 
 Let the glafs be made of a conical form, ter- 
 minating in a ftreight neck. The bafe of the 
 cone may be five inches diameter ; or lefs, in 
 proportion to the quantity of mercury to be 
 calcined in it. The height, from the bafe tp 
 the neck, may be feven inches ; and that of 
 the neck three. About two inches from thp 
 bottom, let there be two fhort tubes inferted, 
 bending in a round, fo that the mouths may 
 be downwards. The top of the neck fhould 
 be, likewife, fo turned, that the mouth may 
 bend downwards, to prevent its receiving any 
 duft, or foot, that might otherwife fall intg 
 the glafs among the mercury. 
 
 Of lutes. 
 
 There are a great variety of lutes in ufe 5 
 rnqft of which; rightly applied, would anfwer 
 
 U fprne 
 
5 o INTRODUCTION. 
 
 fome end ; but the art is, rather the adapting 
 each to its proper purpofe, than the forming 
 the compofition. 
 
 For the making good junctures out of 
 the reach of a burning heat, a mixture of 
 linfeed meal, or wheaten flower, and whit- 
 ing, in the proportion of one part of the firft 
 to tw r o of the laft, tempered with a folution 
 of gum fenegal in water, and fpread upon 
 the joint, a narrow piece of paper fmeared 
 with the fame being put over it, and prefled 
 clofe, will be found fufficient : but even the 
 trouble of this may be greatly (hortned, where 
 the glafles fit each other well, and there is no 
 elaftic vapour to be confined, by the ufe of a 
 narrow piece of bladder fmeared with the 
 white of an egg, or a ftrong folution of gum 
 arabic or fenegal, and fitted to the glafles over 
 the joint. 
 
 In diftillations, where the efcape of part of 
 the vapour is looked upon as a material incon- 
 venience, it may be almoft wholly prevented, 
 by the ufe of quicklime well powdered, and 
 tempered with linfeed-oil, boiled till it acquire 
 a very brown colour, (or drying oil as it is 
 called by the painters.) But this mixture muft 
 be immediately made before it be ufed : and 
 if it be employed, great care muft be taken, to 
 manage the fire, in fuch manner, that the va- 
 pour may not rife fo faft as to heat the refri- 
 geratory, or condenfing veflels, beyond the due 
 point : for it renders the feparate glafles, joined 
 together by it, as one intire body ; and will 
 1 refift 
 
INTRODUCTION. 51 
 
 refift the efforts of the rarefied fteam, to fb 
 great a degree, that the glalfes are liable to 
 burft before it will give way. 
 
 The occafion, where a particular kind of lute 
 is moft material, and where the moft errors are 
 praftifed in the choice, is, when the joints to be 
 made good are fubjedl to acquire a burning heat, 
 during the operation. For here all fuch com- 
 poiitions, as owe their cohering power to ani- 
 mal or vegetable fubftances, are neceflarily 
 burnt, and reduced to the ftate of a mere calx. 
 The following compofition, which, for the fake 
 of brevity, I call the fire-lute, where 1 have 
 occafion to mention it, will, however, ex- 
 tremely well anfwer this end ; and may be 
 made with fmall expence, as the ingredients 
 coft little, and may be prepared in large quan- 
 tities ready for their being mixed together when 
 wanted. 
 
 Take vitriol calcined to rednefs, and pow- 
 dered, two parts, the fcoria or clinkers of a 
 fmith's furnace finely levigated, and Stur- 
 bridge clay, or Windfor loom, dried and pow- 
 dered, each one part; mix them well together; 
 and then temper them with the blood of any 
 beaft ; a twentieth part of their weight of fhort 
 hair being beaten up with them. This is, not 
 only an excellent lute, for all junitures of 
 veffels where they are expofed to & great heat 5 
 but alfo an extremely ufeful cement, for the 
 pointing furnaces, and making good all the 
 joints of any part of them, which are liable to 
 fuftain a burning heat. It is likewife the beft 
 
 E 2 in 
 
52 INTRODUCTION. 
 
 compofition, for coating the outfides of glafs 
 bodies, or other fuch veffels, as are to be ufed 
 in the naked fire, where great caution againft 
 their breaking is requifite - y but, in common, 
 cafes, the following cheaper mixture may be 
 fubftituted. 
 
 Take of fand Windfor loom, or (if good) 
 common loom, and dung of horfes, which 
 feed on hay, each equal parts ; temper them 
 with water ; and beat them thoroughly toge- 
 ther. 
 
 The laft kind of lute, or cement, I fhall 
 mention, is folely, for the repairing the cracks, 
 and replacing the broken pieces, of receivers, 
 or other glafs veffels, which admit of being 
 ufed after they are in that condition ; and this, 
 judicioufly applied, in an elaboratory, where 
 many fuch veffels are ufed, will make a confi- 
 derable faving. 
 
 Take an ounce of Suffolk cheefe, or any 
 other kind devoid of fat ; grate it as fmall 
 as poflible ; put it, together with an ounce 
 of quicklime, finely powdered, into two 
 ounces of milk, from which the cream has 
 been taken away ; mix them well, and ufe 
 the mixture immediately; fpread this upon a 
 narrow piece of linnen rag accommodated to 
 the form of the crack ; and it will make the 
 part equally ftrong, and found, with the reft 
 of the veffel. 
 
 SECTION 
 
INTRODUCTION. 53 
 
 SECTION II. 
 
 General obfervations, on the mojl eafy 
 and profitable 7nethods of performing 
 fever al of the operations of chemiftry 
 and pharmacy. 
 
 Of dijlillation. 
 
 The principal art in diftillatlons, of every 
 fort, confifts in the chafing well the kind of 
 apparatus for each purpofe ■; and adapting, the 
 feveral parts of it, rightly to each other. By 
 a due fkill in, and attention to, thefe, many 
 operations, of a precarious nature, may be 
 rendred afifuredly fuccefsful -, and great faving, 
 in time, trouble, fewel, and the produce of the 
 operation, may be made in the moil eafy and 
 certain manner. 
 
 Spirit of wine, and ail the fpiritous com- 
 pound waters made of it, fimple waters, and 
 eflential, or etherial oils, are beft managed, in 
 the copper ftill with a worm, by the ufual me- 
 thods : except, that the making the fireplace 
 fo forwards, under the brickwork of the fur- 
 nace, as is generally done, is a very grofs 
 fault. For it fhould be always thrown as far 
 towards the center, as the dimenfions of the 
 body of the ftill will admit, and, though this 
 is limited, in a very large apparatus, yet the 
 fire fhould be under fome part of the bottom 
 
 E 3 of 
 
54 INTRODUCTION. 
 
 of the ftill, in all cafes ; and as much of that 
 expofed to it, as is confident with the bearing, 
 it requires to have, on the brickwork. In the 
 cafe of fmali ftill s, they may be hung free of 
 any brickwork, in the body of the furnace, 
 after the manner directed for the fand-pots* 
 
 The diftillation of acid fpirits is beft per- 
 formed in retorts, in the fand-pot. Thofc, 
 chofen for this purpofe, fhould have a large 
 low bulb, and a low long neck ; and be placed 
 deep in the pot ; that the vapour, which can 
 only be fufpended in a great degree of heat, 
 may rife over the helm * and not circulate in 
 the body of the retort, nor be condenfed in 
 that part of the neck, which is not depending 
 With refpeft to the receiver. 
 
 In the diftillations of fuch bodies, where two 
 fubftances are put into the retort to a£t on each 
 other by commenftruating powers, as oil of 
 vitriol, or fpirit of nitre and mercury, and 
 fpirit of nitre and fea-falt, care muft be taken, 
 if a firm lute be ufed, to leave a fmall vent. 
 For a great quantity of air being generated, in 
 the adion of thefe bodies on each other, which, 
 from its not being capable of fuffering any con- 
 denfation, will neceffarily force a paffage fome- 
 where, if none be left for its efcape, if the 
 lute refift fufficiently, it muft confequently 
 burft either the retort or receiver. The fame 
 caution fhould be obferved in other operations, 
 where feparations are made of compound 
 bodies, by the medium of others ; as alfo in 
 the diftillation of animal or vegetable fubftances, 
 
 where 
 
INTRODUCTION. S5 
 
 where they are analyzed by a burning heat. In 
 all which cafes, air is copioufly produced \ and 
 will never fuffer itfelf to be confined. From the 
 want of knowing, or attending to, this circum- 
 ftance, many operations are conduced, fo as 
 \o occafion nufance and danger to the opera- 
 tor, as well as lofs of the diftilling matter, 
 which might otherwife be rendred fafe, in- 
 offenfive, and much more profitable. Amber 
 may be alfo beft diftilled in retorts in the fand- 
 pot ; but they ought, in this cafe, to have very 
 large long necks, with a wide orifice - y as well 
 that the fait may all fix in the neck, as that it 
 may be eafily got out of it. The diftillation of 
 animal fubftances, where the quantity is fmall, 
 may be alfo performed in the fame manner. 
 
 The diftillation of a variety of different fub- 
 ftances is beft performed in retorts, in the fand- 
 bath, which varying in the degree of heat in 
 the different parts, it is proper to diftinguifh 
 the feveral kinds of fubftances, that may be 
 diftilled in it, into three orders. In the firft 
 may be included the rectification of fpirit of 
 hartfhorn; the produftion of fpirit of fal armo- 
 niac, either by means of fixed alkaline fait, or 
 lime ; the rectification of oil of amber ; and 
 the diftillation of vinegar : for thefe operations, 
 long retorts, with tall and long necks, fhould 
 be chofen; for the water and crudities, being 
 lefs volatile than the fubftance intended to be 
 freed from them, a more perfect feparation 
 will be made, if the vapour circulate within 
 the glafs fo as to fuffer the water to be con- 
 E 4 denfed 
 
|4 INTRODUCTION, 
 
 denfed againft the fides : except in the cafe of* 
 vinegar, where the retort fhould have a large 
 bulb, arid lower neck, as the acid, which is 
 the objeft of the operation, is lefs volatile than 
 water 5 and apt to remain in the retorts, even 
 when every advantage is taken; 
 
 In the fecond order may be placed fal vola- 
 tilis arornaticus, fpiritus nitjri dulcis, fpiritus vi- 
 trioli dulcis, fpiritus lavendulae compofitus ; 
 and fome others. 
 
 In the laft order may be put highly re&ified 
 fpirit of wine, or alcohol when wanted : or 
 the fpirit. nitri; or vitriol. dulcis 3 or fpir. lavend. 
 compos, may, on occafion, fill even the 
 cooleft part without any inconvenience. By 
 obferving this fyftem of management, and al- 
 ways contriving, that every part of the fand- 
 bath fhall be employed, whenever the furnace 
 is fet to work, great favings will be made in 
 trouble and fewel : and, though it is not eafy 
 to adapt the feveral operations, thus carried on 
 together, in fuch manner to each other, that 
 they may be all finifhed at the fame time ; yet 
 there will no inconvenience arife from that, 
 where proper means are ufed. For an expert 
 operator may, without difficulty, change the 
 exhaufted retorts for others, frefh charged, in 
 any part of the furnace, even when > it is in 
 the hotteft ftate ; a praftife, I can aflert to be 
 'extremely advantageous, arid no way hazard- 
 ous, when due care is taken 3 though hitherto 
 fo much negledled, that I never knew it fol- 
 lowed except where directed by myfelf. 
 
 In 
 
INTRODUCTION, 5? 
 
 In diftillations, made in retorts, it is of great 
 confequence, to have the receivers as large as 
 poflible ; as it renders the operation both much 
 quicker and fafer, to have a fufficient quantity 
 of condenfmg fubftance* 
 
 Of Jublimdtkn. 
 
 The fublimation of fal Ammoniacum, irk 
 order to produce the flowers, or the ens veneris, 
 as alfo of the volatile fait, when obtained by 
 means of chalk, is beft performed, in retorts, 
 in the fand-pot. The retorts fhould have large 
 bulbs, and low, but very wide necks. 
 
 The heat of the fand-pot is alfo fufficient, 
 for mercury fublimate ; which may be beft 
 managed in a very large glafs body of an oval 
 figure : but this kind of furnace is not to be 
 depended upon with regard to cinnabar, which 
 cannot with certainty of fuccefs, be treated in 
 any other way than in an earthen, or glafs body 
 luted, and expofed naked to the fire. In the re- 
 ctification of fait of amber, fal cornu cervi, orfal 
 volatile Ammoniacum, the fublimation may be 
 beft performed, in the fecond ftage of the fand- 
 bath, in low retorts, with very fhort necks, and 
 wide orifices. In the fublimation of volatile 
 falts, great care muft be taken, that the heat 
 be not too great : and if it cannot be kept 
 under, without delaying too much the con- 
 comitant operations-, in the fand-pot and the 
 fand-bath, the fand fhould be removed from the 
 retorts containing the fubliming matter -, and 
 
 they 
 
5 S INTRODUCTION. 
 
 they fhould be raifed higher. But a little 
 clofe obfervation will fhew the proper depth, 
 in which they ought to be placed in the fand- 
 bath ; and the height of the retort fhould be 
 regulated accordingly : for if the neck ftand 
 too high above the fand, the falts will collect 
 in it, and choak it up, inftead of pafling into 
 the receiver* 
 
 Though large receivers are recommended 
 for diftillations, yet fmall ones fhould be ufed 
 for the fublimation of falts ; as the cake formed 
 againft the top and fides will otherwife want, 
 both that denfity, and thicknefs, which are 
 neceffary for their keeping well, and their fa- 
 lable appearance. 
 
 Of calcination* 
 
 Calcination is performed on two principles, 
 by calefa&ion, that is, by the heat communi- 
 cated by means of exterior fire : and by igni- 
 tion ; that is, where the matter is calcined by 
 the fire generated within itfelf, by means of 
 its own combuftion ; and this is effcfted either 
 by admiffion of air to the accended body ; or 
 by the admixture of nitre, which when ufed for 
 this purpofe, occafioning an ^xplofive appear- 
 ance, the chemifts have called the operation, de- 
 tonation, or deflagration. 
 
 Where large quantities are to be calcined by 
 the firft principle, as in the cafe of hartfhorn, 
 a large furnace like, in form, to that of the 
 potters or tobacco-pipe-makers, fhould be had$ 
 
 or 
 
INTRODUCTION. 59 
 
 or otherwifc, where the oecafion is but rare, 
 the matter may be fent to the furnaces of that 
 kind, and there prepared at a very fmall ex- 
 pence. 
 
 Where deflagration is to be praftifed, as ill 
 the procefs for crocus antimonij of the London- 
 College, Antihedicum Poterij, &c. the wind- 
 furnace muft be ufed -, and the operation per- 
 formed in a crucible, raifed on a fmall earthen 
 ftand, about two or three inches above the bars. 
 The matter fhould be thrown in gradually, with 
 great caution ; efpecially when the crucible is 
 filled to any confiderable height ; for the effer- 
 Vefcence will frequently, otherwife, throw out 
 a great part of the contents. But in the pre- 
 paration for the crocus melallorum, according 
 to the former proceffes, a method has been 
 taken to avoid the ufe of any furnace, for the 
 effecting the deflagration, the particulars of 
 which we fhall exhibit in its proper place : only 
 an iron pot, fuch as is ufed for culinary purpofes, 
 fhould be provided for the performing this pro* 
 cefs : its magnitude muft be fuch as will admit 
 its containing all the ingredients together, which 
 are intended to be ufed. 
 
 Of filtration. 
 
 Though this Ample operation has been hi- 
 therto much neglefted, and the cotnmon ap- 
 paratus very imperfedl; yet it is of great con- 
 fequence, in commercial fchemiftry, that there 
 ibould be fbme method, by which it may be 
 
 performed, 
 
60 INTRODUCTION, 
 
 performed, with eafe and expedition, where 
 great quantities come in queftion. 
 
 Filtration is generally praftifed, by means 
 either of flannel cloth, or paper : for the firft 
 of which, the comtnon method of ftraining 
 through a bag of a conical form, which kind 
 was formerly called Hippocrates's fleeve, is 
 convenient enough ; but, where paper is re- 
 quired, the earthen cullenders, before de- 
 fcribed, p. 32, fhould be ufed. 
 
 As the end of filtration is of two kinds, the 
 one to purify fluids from any folid bodies, they 
 contain, of a feculent nature; the other, to free, 
 fome precipitated powder or body, from the 
 fuperfluous fluid with which it is mixed ; the 
 means muft be fomewhat varied. In the firft, 
 paper, if it be of the right kind, is fufficient ; 
 but, in the other, coarfe cloth fhould be put 
 over the paper ; otherwife, in taking the fil- 
 tred mafs from it, parts of it will unavoidably 
 intermix themfelves with, and incurably foul, 
 the matter. 
 
 The manner of ufing the earthen cullender, 
 is to fet it upon a proper wooden ftand, of a 
 fquare form ; in which it muft hang by its 
 edges. Under it muft be placed a glafs re- 
 ceiver, with a large funnel of the fame fub- 
 ftance, the diameter of whofe mouth muft be 
 larger than the bottom of the cullender, that 
 the ftreams or drops, which fall from the holes, 
 may be caught by the funnel, and run through 
 its pipe into the receiver. 
 
 In 
 
INTRODUCTION. 6r 
 
 In fetting the filters of this kind to work, 
 great care muft be taken, to accommodate 
 rightly the paper to the cullender, as well as 
 to pour the fluid very flowly into it at firft. 
 For otherwife, the paper will certainly burft, 
 and delay the operation by fouling all the 
 veflels with the unfiltred matter. 
 
 There is not any kind of paper, at prefect 
 manufactured, which is fo good for this ufe 
 as might be : but the beft, that is to be had, 
 is the fort called bloom paper ; though even 
 that frequently is fo faulty, as not to anfwer, 
 in almoft any degree, the end : where it is 
 found to be of fo loofe a texture, as to relax, 
 in fuch manner, as not to bear the weight of 
 the fluid, poured upon it ; or where otherwife 
 the fluid itfelf is of fo relaxing a nature, that 
 it deftroys the texture even of good paper ; a 
 coarfe linnen cloth muft be ufed, along with 
 the paper, even though the purification of the 
 fluid, only, be the end. But in this cafe, it 
 muft be ufed differently from the manner be- 
 fore direfted. For the paper muft here be put 
 over the cloth, inftead of being under it : as 
 the defign of ufing both, is only to give ftrength 
 to the paper. 
 
 In filtering large quantities, it will be fre- 
 quently found, that after the paper has been 
 foaked in the wet, for fome time, the opera- 
 tion will proceed very flowly : the fwelling of 
 the fubftance of the paper, as well as the foul- 
 nefs of the fluid, diminifhing, and at laft choak- 
 ing up, the percolating pores. In this cafe the 
 
 paper 
 
62 INTRODUCTION. 
 
 paper fhould always be changed, immediately 
 after the filter ceafes to run moderately j other- 
 wife the operation would be intolerably tedious. 
 
 Of levigation. 
 
 When great quantities of teftaceous or cre- 
 taceous powders are to be levigated, the moft 
 cheap and expeditious method of operation is 
 by the horfe-mills, beforementioned ; where 
 the fame machine, that grinds, likewife fearces 
 the matter. 
 
 This fo much fhortens the work, that the 
 wholefale dealers find confiderable advantage, 
 in putting out quantities of materials for pow- 
 ders, to a perfon, who has erefted a machine 
 i)f this kind ; and levigates the feveral fpecies 
 of bodies at certain rates : but, befidesthe im- 
 pofitions, which thefe methods of intruding 
 others, with the preparation of medicines, of 
 which the genuinefs is not eafily diftinguifhed, 
 gives room for, by exchanges or adulterations. 
 The powders can never be made of near fo 
 great a degree of finenefs, by this manner of 
 grinding and fearcing, as when levigated, by 
 the muller on a proper ftone, or marble, efpe- 
 cially, if the following method (ufed originally 
 by the preparers of colours, and called by 
 them wafhing over) be fuperadded to the 
 levigation. 
 
 The matter being firft well levigated, or, if 
 it be a cretaceous body broken, to a grofs pow- 
 der, by pounding, let it be put in a deep 
 
 veflel 
 
INTRODUCTION. 63 
 
 veilel almoft full of water, and there well 
 ftirred. Then having refted a fhort time, that 
 the grofler parts may fink to the bottom, let 
 the water and finer part, yet fufpended, be 
 poured off into another veilel ; and fuffer- 
 ed to ftand at reft, till the powder, poured 
 off with the water, has totally fubiided : 
 let the clear water be then poured back, into 
 the firft veflel, with great care not to difturb 
 the fubfided powder, and let the ftirring, de- 
 cantation, &c. be repeated as before, fo often 
 as (hall be found neceflary, to feparate all the 
 powder, which is of fufiicient finenefs. The 
 remaining groffer part may be again ground ; 
 and the fame treatment continued, till the 
 whole of the matter he obtained fine. By this 
 method, executed with care, impalpable pow- 
 ders may be had, with great eafe, from even 
 the hardeft bodies ; and chalk, tobacco-pipe- 
 clay, and fuch other earthy fubftances, as grow 
 ibftin water, may be freed from fand or other 
 impurities, and rendred fine, without grinding. 
 
 Of chryftallization. 
 
 Where only moderate quantities of falts are 
 required to be chryftallized, this operation is 
 beft performed, by the large glafs receivers, 
 &c. mentioned p. 33, into which, the folu- 
 tion of the falts being put, and continued till 
 the chryftals be duly formed, the fluid muft 
 be firft poured off, into another receiver, and 
 then the receiver and bafket, containing the 
 
 cake 
 
64 INTRODUCTION. 
 
 cake of chryftals, reverfed over the bafket-work 
 funnel, and there fufFered to remain till the 
 fluid be drained off; the falts muft then be laid 
 upon a board, gently Hoping, till they be of 
 a proper drynefs. 
 
 Where very large quantities of falts are to 
 be chryftallized, the leaden ciftern, &c. men- 
 tioned p. 33, muft be employed. The folu- 
 tion being drawn off from the boiler into the 
 ciftern 5 and the chryftals, when they are form- 
 ed, taken out, and put into the bafkets placed 
 over it, till the fluid be drawn from them 5 
 and then laid to dry on the flat frames of 
 bafket-work. 
 
 The great object of art, in chryftallization, 
 is the making the folution of a due ftrength : 
 for, if it be not fufficiently faturate, the pro- 
 duce of chryftals will be fmall ; and if it be 
 overcharged, the fait will fhoot fo fuddenly, 
 that a great number of very fmall chryftals, 
 like powder, will be formed 3 and coalefce, in 
 a kind of cake, on the furface of the contain*- 
 ing veffel ; which, mixing with the larger 
 chryftals, that will fhoot afterwards, will make 
 them appear dull and lefs fightly. It is, there- 
 fore, very requifite to obferve the due point of 
 faturation : which may be gained, by bringing 
 the folution to that ftate, in which it will afford 
 no chryftals till it be cool, and then produce, in 
 a fhort time, fhoots like needles, inftead of the 
 powder beforementioned : which will happen 
 in moft kinds of falts, where the chryftals are 
 of a long form, if the folution be charged in a 
 
 1 proper 
 
INTRODUCTION. 6$ 
 
 proper degree. It may be eafy, for any, who 
 defire to perform this operation with accuracy, 
 to find out the fpecific gravity of the folution 
 of each kind of fait when duly faturated for 
 chryftallizing ; which, being once known, is a 
 ftandard for regulating their proceedings by 
 the moft eafy means. Btit proper allowance 
 muft be made for the feafon of the year ; for, 
 in fummer, falts are much more difpofed to 
 /hoot than in winter ; and the fame muft be 
 obferved, likewife, with regard to the degree 
 of heat, or cold, in the place where they ftand 
 to fhoot. When from accident of weather, 
 or fituation, they are kept warm, the folution 
 may be ftronger, and much longer time muft 
 be given for the formation of the chryftals : 
 the contrary will hold good with refpeft to 
 winter, or accidental cold. 
 
 It may be taken as a certain principle, like- 
 wife, that, whenever falts fhoot faft, the fingle 
 chryflals will be proportionably fmaller. 
 
 r 
 
 F SECTION 
 
66 INTRODUCTION. 
 
 SECTION III. 
 
 Examination of the famenefs of fever al 
 fubflances, which make a part of the 
 materia medica under different deno- 
 minations^ without any effential diver- 
 fity ; being neceffary for the deter min- 
 ings how far many fubjlitutions are 
 allowable. 
 
 Of the famenefs of all fixt alkaline falts y from 
 whatever vegetables^ or parts of vegetables^ 
 they may be produced. 
 
 The fixt alkaline falls of vegetables can be 
 produced, by no other means, than the inci- 
 neration, or burning to afhes, the proper parts 
 of thofe vegetables, which can afford them. 
 For all vegetables do not afford them, in any 
 degree $ and fome, only, from certain parts. 
 If, however, the fixt alkaline falts, thus ob- 
 tained, from any vegetable whatever, be ex- 
 pofed to a ftrong and continued heat, or be de- 
 flagrated with nitre, they will be found, on the 
 niceft examination, by any experiment, to be a- 
 likein all their qualities; except that difference, 
 which the degree and duration of the heat, they 
 have been expofed to, will be found to caufe, 
 promifcuoufly, in all. 
 
 The 
 
INTRODUCTION. 67 
 
 The fuppofed difference, thereibre, betwixt 
 the falts of feveral kinds of vegetables, as of 
 wormwood, broom, or tartar, does not con- 
 fift, really, in the falts themfelves ; becaufe, it 
 may be deftroyed by calcination in a ftrong 
 heat; and yet, there being an apparent dif- 
 ference, in fuch as have not been ftrongly cal- 
 cined, it muft neceffarily arife from the admix- 
 ture of fome other fubftance, with the falts ; 
 that is expelled or taken away by the heat of 
 a ftrong calcination. This can be nothing but 
 part of the oil of the vegetable ; which, be- 
 ing attracted by the fait, remains conjoined with 
 it, even though the fait be purified by folution, 
 and filtration ; and being thus infeparable from 
 the fixt alkaline fait, while it remains fuch, by 
 means of water or any other medium, except 
 intenfe heat, appears to mark the fait with a 
 fpecific charadler ; giving occafion to fuppofe, 
 a real diverfity, betwixt the falts of different 
 vegetables, or parts of them, dependent on 
 the different nature of the vegetables : where- 
 as there is, in £z& } no difference, but betwixt 
 thofe, which have undergone incineration only, 
 and thofe which have undergone a ftronger, or 
 more continued calcination ; as in the inftance 
 of the falts of wormwood and tartar. For if 
 the fait of wormwood be deflagrated with 
 nitre, or fubje&ed to a ftrong calcination, or 
 the fait of tartar combined with a fmall quan- 
 tity of the burnt oil of wormwood, they will 
 then reciprocally change their characfleriftic 
 F 2 qualities 5 
 
68 INTRODUCTION. 
 
 qualities ; and each will acquire that, which 
 before diftinguifhed the other from it. 
 
 From experience, rather than philofophic 
 knowledge of the truth of this principle, fait 
 of tar ar has been fubftituted, either by the 
 prefcribers or compounders, in the faline febri- 
 fuge draughts, very generally, in the place of 
 fait of wormwood ; and purified pearl-afhes 
 are fold, by the wholefale dealers, almoft con- 
 ftantiy, in the place of fait of tartar : and where 
 the appearance of fait of wormwood mud be 
 preferved, in conformity to the prejudice of 
 thofe who have not yet got over this error, 
 either the fait of tartar, or purified pearl-afhes, 
 are rendred of a proper degree of foulnefs, to 
 give them the brown colour of the genuine 
 fait of wormwood ; and pafled for it. 
 
 The famenefs of fixed alkaline falts has 
 been, however, oppofed by fomeperfons, who, 
 in very nice experiments, have found the fait 
 >of wormwood a menftruum for particular bo^ 
 dies, which the fait of tartar would not a<5t 
 upon, in a fimilar manner ; the difference in 
 thefe experiments does not, however, lie, in the 
 falts, from their own nature, but in the pre- 
 fence of another fubftance conjoined with the 
 fait of wormwood, to wit, the burnt oil of 
 that vegetable, which aided the fait in its 
 operation on the bodies by which the experi- 
 ment was made : for freeing the fait of worm- 
 wood, from this impurity, or giving it to the 
 other, will eafily ihew the fallacy of thefe ex- 
 periments, 
 
 -i 
 
INTRODUCTION, 69 
 
 periments, with refpeft to the conclufion from 
 them, of the aftual difference of the falts. 
 
 In order to judge, neverthelefs, how far the 
 fubftitution of one kind of fixt alkaline fait, in 
 the place of another, may be allowable, it is 
 neceffary to confider, whether a part of the 
 efficacy of fuch falts, as medicines, may not 
 refide in the oil, or appertain to them, in fome 
 manner, in confequence of this impure ftate. 
 
 With refpe<ft to the efficacy, which the oil 
 itfelf may poffefs, when we confid.er it as a 
 diftind: part of the medicine, we mull afcribe 
 it to the general properties, that belong to all 
 vegetable oils when burnt. For (as we fhall 
 fee below) all vegetable oils, or fulphurs, after 
 they have fuffered the aftion of the fire fo as 
 to be burnt black, lofe the fpecific qualities, 
 they before had, as parts of the particular 
 plant, which produced them ; and acquire 
 qualities commom to them all in this ftate y 
 differing only in the degree of thofe qualities, 
 according to the greater or lefs aftion of the 
 heat, and according to the other elementary 
 fubftances of the parts of the vegetables, in 
 which they refided. 
 
 If we therefore allow, that the oils peculiar 
 to the plants, they are obtained from, retain no 
 fpecific qualities in this ftate ; the efficacy, they 
 may give to the alkaline falts as a medicine, 
 muft confift in thofe, which are common U 
 all burnt oils. And however the property ot 
 fuch oils might fometimes make for the inten- 
 tion of the remedy, yet the filial] quantity, in 
 
 F 3 which 
 
7 o INTRODUCTION. 
 
 which they can be here adminiftered, would 
 take off from any ftrefs, which could be other- 
 wife laid upon them. But the fadt is, that the 
 alkaline and diffolving qualities of the fait are 
 thofe alone, by which thefe medicines, in al- 
 moft all cafes, produce their effe<fts ; and to 
 thefe the additional prefence of the burnt oil is 
 not at all neceffary. 
 
 If the adion of burnt oils, confidered ac- 
 cording to the fmall proportion of it found in 
 a dofe of alkaline falts, be infignificant, even 
 in cafes where its qualities might in fome de- 
 gree correfpond with the intention of the me- 
 dicine ; and if in other cafes, which are the far 
 greateft part, it is no way relative to the inten- 
 tion > it remains to inquire, whether by the 
 combination of the oil and fait, a tertium quid, 
 er third kind of fubftance may not be gene- 
 rated ; which may have properties different 
 from thofe of the pure fait, diverted of the 
 oil ; or of the oil while in its fimple ftatc. 
 
 It muft indeed be admitted according to 
 what we have faid above, that the fait and oil 
 conjoined may have fome properties, different 
 from the pure fait ; but they are fuch as ap- 
 pear foreign to the apparent caufe of the me- 
 dicinal efficacy of alkaline falts : for, as I be- 
 fore obferved, the quality which belongs 
 to them, as alkalies, in deftroying of acids, 
 and checking acefcence in the via prima, (fo 
 often the caufe of chronic complaints,) with 
 their power of diflblving pituitous humours and 
 concretions in the fecretory veffels^s v/ell by their 
 2 own 
 
INTRODUCTION. 71 
 
 own faponaceous power, as by their ftrengthning 
 the bile, account fufficiently for their effects, 
 in the cure of thofe difeafes, for which they 
 have been hitherto adminiftered. And it would 
 be a prefumption, ill founded, to fay, that, be- 
 caufe the adtion of the fait was fomewhat varied, 
 by its combination with the oil, in refped: to 
 fome particular bodies of a nature foreign to 
 thofe, which relate to the human conftitution, 
 (as in a very large field of experiment might 
 be found to be equally true of almoft any com- 
 pofition that could be made) it was therefore 
 owing to thefe obfcure, partial, and weak, and 
 not their very powerful general qualities, (tho' 
 accounting clearly for all the particular effefts,) 
 they owed their medicinal operation. 
 
 It may therefore be deemed an allowable 
 (that is to fay, with refpedt to the medicinal 
 effects, an innocent) fubftitution, to ufe the 
 fixt alkaline fait of one vegetable, or part of a 
 vegetable, for that of another : provided there 
 be no impurity, or defect as to the general na- 
 ture, in the fait fo ufed : and it would be much 
 better, in order to avoid impofitions with refpedt 
 to price, and thofe other frauds of the fame 
 kind, with which the prefent practice is greatly 
 replete, that the college would eftablifh this 
 doctrine in their pharmacopeia ; and prefcribe 
 only fixt alkaline falts in general : leaving it to 
 thofe, to add the burnt oil of wormwood, or 
 any other vegetable, in their extemporaneous 
 prefcriptions, who may think it appofite to the 
 particular intention of cure. 
 
 F 4 Of 
 
72 INTRODUCTION. 
 
 Of the famenefs of volatile alkaline falts, from 
 whatever animals, or parts of animals, they 
 may be produced. 
 
 What is above faid of the fixt alkaline falts 
 of vegetables, is equally true of the volatile 
 alkaline falts of animals. For, nature having 
 formed all thefe kinds from the fame ele- 
 ments, thofe combinations, which give the 
 fpecific form to each, are deftroyed by the re- 
 folution made by fire or putrefaftion $ and new 
 ones are produced, not according to thofe modes 
 of combination, which the fire deftroyed, and 
 which are producible only by the power of ve- 
 getation ; but according to the general quali- 
 ties of the elements, and their proportionable 
 quantities to each other. 
 
 This will be found true, with refpeft to vo- 
 latile alkaline falts, by experiments made on the 
 fame principle with thofe beforementioned, for 
 proving the famenefs of the fixt alkaline falts. 
 For, if volatile alkaline falts be fo purified by 
 rectification, or any other method, that the oil 
 be intireiy taken away from them, they will 
 appear alike in all their qualities ; and, alio, if 
 the oil of one kind be added to the other, in a 
 pure flate, it will refemble that intireiy from 
 which the oil was borrowed. As, for example, 
 if fait of hartfhorn be commixt with fpirit of 
 fait, and confequently formed into fal Ammo- 
 niacum, and the volatile fait afterwards again 
 feparated, by the addition of fixt alkaline falts, 
 
 it 
 
INTRODUCTION. 73 
 
 it will be found, then, to be the fame in every 
 point, as if feparated from the fal Ammonia- 
 cum brought from the eaft : or, if to the vola- 
 tile fait of fal Ammoniacum, obtained from the 
 eaftern kind, the oil diftilled from hartfhorn be 
 added, the fait will perfe&ly refemble that ex- 
 tracted from the horn. 
 
 With refpedt to the pure volatile alkaline fait 
 of any animal, or part of an animal, the vola- 
 tile fait obtained from fal Ammoniacum might 
 well be fubftituted ; and the fame holds good 
 with regard to what is called volatile fpirit, 
 which is, in fa£t, only the fait diffolved in wa- 
 ter : but thofe, which are ufed in medicine 
 under the name of particular falts or fpirits, are 
 greatly replete with the diftilled oil, that arifes 
 along with the falts 5 and which is not, as the 
 burnt oil in the cafe of the fixt alkaline fait 
 of vegetables, either irrelative, or inadequate 
 to the intention of the medicine ; but, on the 
 contrary, a proper and eflential part of it : and 
 therefore volatile fpirit of fal Ammoniacum, 
 cannot be fubftituted for fpirit of hartfhorn, 
 without a material defeat •> unlefs an equiva- 
 lent quantity of the fame kind of oil be previ- 
 oufly conjoined with it. But if a volatile fpirit, 
 or fait, be drawn from any other fort of animal 
 fubftance, and be replete with an oil of the fame 
 kind, in a ftate equally, or more, fuitable to the 
 intention of this medicine, they may well be 
 fubftituted for thofe of hartfhorn, vipers, or 
 any other particular materials, which the fancy 
 of perfons ignorant in principles of this kind 
 
 may 
 
74 INTRODUCTION. 
 
 may dired. And the fubftitution of any other 
 volatile fpirit, inftead offpirit of hartfhorn, pro- 
 vided it be duly replete with volatile fait, and di- 
 ftilled animal oil of the more ethereal kind, may 
 indeed be conlidered as a fraud in commerce, 
 but is in fad: an improvement in medicine. 
 
 Of the famenefs of ' oils> dijlillcd from the fever al 
 kinds > or parts of animals. 
 
 There is no part of any animal, which will 
 afford an oil by diftillation, till the fame be 
 burnt, and the oil rendred ethereal by heat : yet, 
 neverthelefs, not only the adipofe, or fat parts, 
 but even any other, if they be expofed to a cer- 
 tain degree of heat, neceflarily afford an oil 
 which rifes from them, in the ftate of vapour ; 
 and may be collected by proper condenfing 
 veffels. In this btu lit ftate, the form and fpeci- 
 fie qualities, which the oils might have in their 
 original ftate, are loft ; and, like fixt or volatile 
 alkaline falts, they put on a general nature, 
 which has no dependance on, or affinity with, 
 the fpecific qualities of the animals, or parts, 
 whence the oils are ex traded, but is fimilarin all. 
 
 There is, however, a variation in diftilled 
 oils, not found in alkaline falts ; though none 
 arifes from the peculiar qualities of the animals, 
 or pans that afford them; for, in all the feveral 
 parts of animals, the fulphureous principle, or 
 phlogifton, which is the proper eflence of all 
 oils, is more ftrongly combined, in fome of 
 the fubftances, which conftitute thofe parts, 
 
 with 
 
INTRODUCTION. y S 
 
 with earth and acid, than in, others > and, being 
 thus attrafted by the earth, or reduced by the 
 controlling power of the acid nearer to the ftatc 
 of a fixt fulphur, raifes with itfelf, in the diftil- 
 lation, a greater proportion of thefe hetero- 
 geneous bodies $ and, confequently, produces 
 a grofler and lefs volatile oil ; in which, the 
 heat not having made a more perfeft refolu- 
 tion of the elements, it is yet fubjed:, in fpmc 
 degree, to that tendency to the putrefactive 
 analyiis, that is common to all the parts o£ 
 animals : while, from other fuhftances,in which 
 the phlogifton is lefs intangled with the earth, 
 or acid, the oil rifes of a more pure, Am- 
 ple, and, confequently, unchangeable nature ; 
 having that greater degree of lightnefs, vola- 
 tility, and limpidnefs, which brings it to what 
 is called the ethereal Hate. 
 
 The difference, therefore, in oilsdiftilled from 
 animal fubftances, not arifing from any differ- 
 ence of the kinds of animals, or parts of them, 
 whence they are obtained : thofe extracted from 
 one kind may be, with propriety, fubflituted, 
 for thofe extracted from others \ provided the 
 general qualities of fuch oils, be fuch as are- befl 
 fuited to the particular purpofe then in quef- 
 tion. And though the knowledge of this prin- 
 ciple concerns not greatly the pradtice of medi- 
 cine, with refped: to the ufe of the oils in their 
 fimple ftate, as they are feldom fo adminiftered ; 
 yet, as the prefence of fuch oils give in part the 
 efficacy to fome generally efteemed capital me- 
 dicine, as well as to others, celebrated by par- 
 ticular 
 
76 INTRODUCTION. 
 
 ticular pcrfons only, it was neceflary to beun- 
 derftood, in order to judge of the allowablenefs 
 of certain fubftitutions we fhall have occafion 
 hereafter to fpeak of. 
 
 Of thefamenefs, in quality > of the burnt oils of 
 vegetables > from whatever kind produced. 
 
 What has been before faid of the alkaline 
 falts, and the diftilled oils of animals, is equally 
 true, with refpect to the burnt oils of vegeta- 
 bles : for the fire intirely deftroys thofe com- 
 binations, on which their fpecific form and 
 properties, in the plants, depend ; and pro- 
 duces fuch, as relate only to the general pro- 
 perties and proportion of the elements, of which 
 all are conftituted. Where, therefore, any flip- 
 pofed difference, in medicines, lies in the burnt 
 oil, it may be concluded of no confequence ; 
 nor does it matter from what different vegeta- 
 bles, or parts of them, any fuch medicine be 
 prepared ; but one may equally well be fubfti- 
 tuted for the other, if the form and general 
 qualities are correfpondent in each. This muft 
 not, however, be underftood to extend to fuch 
 oils, as fubfift, in an ethereal or eflential ftate, 
 in the vegetable ; and may be obtained, by di- 
 flillation, with lefs than a burning degree of 
 heat. 
 
 Of 
 
INTRODUCTION. 77 
 
 Ofthefamenefs of the calcined earths of allanimaly 
 and vegetable, fubjlances. 
 
 The earth, which makes the bafis or folid part 
 of all animal and vegetable fubftances, is of one 
 kind y and is never fo changed, by its combina- 
 tion with other bodies, but that a perfect cal- 
 cination wiil reduce it again to its original ftate. 
 
 This being admitted, it refults, that the feve- 
 ral teftaceous or calcined earths of animals or 
 vegetables, ufed in medicine, can be no ways 
 different, with refped: to the earth itfelf : but 
 that where there is a real diverfity, it muft be 
 owing to the prefence of fome other fubftance. 
 In thofe, which have undergone no calcination, 
 or but a flight one, a greater or lefs proportion 
 of the animal gluten, or oil which formed it, 
 will neceffarily be found : and, in fome, where 
 the calcination is more perfect, the fubftance, 
 which gives quicklime its peculiar acflion, will 
 be generated y as in the cafe of the oyfter fheils. 
 But, if the calcination be perfect, and the calcari- 
 ous gas be feparated by frequent ablutions, the 
 earth will at length be found the fame, in every 
 inftance. 
 
 The teftacea, therefore, in all which, there 
 is fome quantity of the animal gluten, though 
 the proportion be different according to the dif- 
 ferent tenacity of each kind, may be fubftituted 
 for each other ; as there is no diverfity in them, 
 but what relates to the proportion of gluten ; 
 and confequently not to the qualities of the 
 
 earths, 
 
78 INTRODUCTION. 
 
 earths, on which their medicinal virtue depends ; 
 that is to fay, to their power of abforbing, or 
 more properly neutralizing, acids. 
 
 The animal and vegetable earths of all kinds, 
 perfectly calcined, may likewife be fubftituted 
 for each other: if the quality, peculiar to quick- 
 lime, be not wanted ; and thofe, in which this 
 quality may be found, be freed from it by 
 wafhing. 
 
 But, where calcined animal fubftances are to 
 be ufed as lime, there will be found an eflen- 
 tial difference, in the produce of the calcina- 
 tion, with refpeft to different kinds j which 
 difference, though not really exifting in the 
 earths themfelves, but caufed by their combi- 
 nation with another fubftance, yet being necef- 
 fary to the intention of the medicine, renders 
 it proper, that the particular kind of animal 
 fubftance, prefcribed, fhould be ftri&ly adhered 
 to. For, if the queftion fhould be, with regard 
 to the fubftitution of calcined hartfhorn for 
 oyfter-fhells ; we fhould put a fubftance that 
 wants, or but in a very fmall degree pofTefTes, 
 the peculiar quality of quick-lime, for one, 
 which has it in a very great degree. 
 
 It is ufual to fubftitute chalk for all the tefta- 
 cea, and calcined earths of parts of animals; 
 but this is by no means allowable : for there is 
 not only an effential diverfity, in the medici- 
 nal qualities, betwixt foffile earths, and thofe 
 of animal or vegetable fubftances ; but even 
 betwixt almoft every different fpecies of the 
 foffile earths themfelves : and though the alka- 
 line 
 
INTRODUCTION. 79 
 
 line qualities of the chalk gives it a great affi- 
 nity to the animal earths, , as operating in the 
 fame intention ; yet an aftringent ftyptic qua- 
 lity, fuperadded to its alkaline, renders it, in 
 fome cafes, by no means a fit fubftitution for 
 the teftacea. : 
 
 Of the famenefs of vinous fpirits ^ from whatever 
 materials obtained. 
 
 As nothing can produce vinous fpirit, but 
 the faccharine juice of vegetables, changed by 
 fermentation ; fo, when that change is made, 
 there is not the leaft difference betwixt the 
 fpirits produced, from whatever vegetable, or 
 part of a vegetable, they may be obtained. 
 
 This will be evident, on a high rectification 
 of any kind whatever ; for the alcohol will 
 appear the fame, even on examination by the 
 niceft experiments. 
 
 The difference, therefore, of thofe kind of 
 vinous fpirits, which go under different names, 
 is not in the fpirit itfelf, but in the admixture 
 of fome quantity of the effential oil of the 
 vegetable, or particular parts of them, which 
 arifes in the firft diftillation, together with the 
 fpirit y as in the cafe of rum : and fometimes 
 alfo in the admixture of the acid of the fruit, 
 which, coming over with it, dulcifies the fpirit, 
 in the fame manner, as other acids ; as in the 
 inflance of brandy. But the manner of coun- 
 terfeiting the peculiar qualities of the feveral 
 kinds, as well as the deftruftion of them, when 
 
 natural, 
 
8o INTRODUCTION. 
 
 natural, by repeated diftillations, all evince the 
 diverfity not to lie in the fpirit itfelf. 
 
 In tin&ures, therefore, and all cafes, where the 
 flavour is regarded, the kind of fpirit prefcribed 
 ought to be ufed ; to render the medicine what 
 it is intended to be : but, where a fubfequent 
 diftillation is to be made, or where the flavour 
 is covered by the admixture of drugs of very 
 ftrong tafte, any kind of fpirit may be ufed, 
 without the leaft injury to the compbfition : 
 and, indeed, with refpedt to the medicinal 
 efficacy, it is matter of indifference in all cafes. 
 
 Of the famenefs of the acid fpirit to be obtained, 
 from fulphur, vitriol, fal catharticum amarum 
 (commonly called Epfmnfalt), and alum. 
 
 The acid gas commonly called oil of vitriol, 
 or the vitriolic acid, has been formerly fup- 
 pofed to be peculiar to the falts of the vitriolic 
 genus; and not, elfewhere, to be naturally found : 
 but later experience, and more rational inquiries, 
 concerning fubje&s of this kind, have informed 
 us, that it is abfolutely the fame with the acid 
 obtained from fulphur by burning : and the one 
 is now promifcuoufly fubftituted for the other ; 
 or rather, the acid of fulphur is now almoft 
 univerfally fold for, and under the name of, the 
 other : as, by the late improvements of the 
 methods of diftillation of it, this acid can be 
 extracted, much more profitably, from fulphur 
 than vitriol. 
 
 The 
 
INTRODUCTION. 81 
 
 The acid part of the fal catharticum amarum, 
 and alum, is alfo the fame with that of vitriol 
 and fulphur : and though it is rarely diftilled 
 from them, as it can be cheaper obtained from 
 the other bodies ; yet the falts themfelves may 
 be, occafionally, ufed, for neutralizing fixt al- 
 kaline fait, and forming the fal polychreft, or 
 vitriolate tartar ; as it may be depended on, 
 that whatever acid is imparted, to any other 
 body, from fulphur, vitriol, fal catharticum, 
 or alum, is abfolutely of the fame kind. 
 
 Of the famenefs of vitriolated tartar, fal poly chre- 
 Jlum, falprunellce, arid the fal enixum. 
 
 The vitriolated tartar, being immediately 
 made by the admixture of vitriol, and fixt alka- 
 line fait, and the falpolychreftum, being formed 
 from nitre, and fulphur, deflagrated together, 
 the acid of the fulphur being fet loofe in the 
 deflagration to aft on the alkaline bafis, which 
 is fixt alkaline fait, it cannot be denied, but 
 that, if the acids of vitriol and fulphur be the 
 fame, as we have before laid down, and that the 
 acid of the fulphur combine with the alkaline 
 part of the nitre, as is evident, the fait produced 
 by each method muft be the fame : there being 
 no difference in efFedl, whether the elements 
 are mixt fimply together, or combined after 
 their feparation from other bodies, with which 
 they were conjoined, in the manner that hap- 
 pens in the deflagration ; where the proper acid 
 of the nitre, and the phlogifton of the fulphur 
 
 G %i n g 
 
82 INTRODUCTION. 
 
 flying away, in the explofion, leave the acid of 
 the fulphur, and the alkaline part of the nitre, 
 at liberty to a£t on each other. 
 
 The fal prunellae, as made according to the 
 former, and moft general proceffes, is exa&ly 
 the fame as the fal polychreft : equal parts of 
 nitre and fulphur, being ordered to be defla- 
 grated together for the firft ; and as much ful- 
 phur, as will deflagrate with the nitre, for the 
 other: only the falprunellae was caft into cakes, 
 and the fal polychreftum chryftallized. There 
 can remain no doubt, therefore, of their being 
 the fame with each other ; and with the tartar 
 vitriolate. 
 
 The college of Edinburg have, indeed, after 
 Lemery, ordered the fal prunellae to be prepared 
 with a much lefs quantity of fulphur, than is fuf- 
 ficient to analyze all the nitre, by deflagration ; 
 and the fal prunellae, fo made, will, confequent- 
 ly, be a compound of nitre, and fal polychreft : 
 but this method of preparing it has, I fancy, 
 prevailed very little hitherto : the proceffes of 
 Quincy's Difpenfatory, and the other older 
 books, being moft generally followed with re- 
 gard to it. 
 
 Sal enixum being formed by the addition of 
 oil of vitriol to nitre ; which oil of vitriol difpof- 
 fefles the proper fpirit of the nitre of its alka- 
 line bafts, and combines with it ; and this alka- 
 line hafis being, as was faid before, fixt alka- 
 line fait ; it is evident that this fait is the fame 
 with the vitriolate tartar, fal polychreftum, and 
 fal prunellae: being, like them, formed only 
 i of 
 
INTRODUCTION. 83 
 
 of fixed alkaline fait, neutralized by the vi- 
 triolic acid. 
 
 All the above mentioned falts, therefore, or 
 any other preparation of fixt alkaline fait, and 
 the acid of fulphur, vitriol fal catharticum, 
 or alum, in which a neutral fait is formed, 
 may be fairly fubftituted for each other. The 
 elements being, in faft, the very fame: but 
 the refiduum of the nitre and oil of vitriol, in 
 the diftillation of fpirit of nitre, which is fold 
 moft generally in the fliops under the name of 
 the vitriolate tartar, muft be excepted, till it 
 be duly neutralized, for it commonly abounds 
 with a great quantity of redundant acid left 
 behind with it in the retort after the diftilla- 
 tion. 
 
 Gz PART 
 
PART II. 
 
 Of the preparation of chemical medi- 
 cines : with the feveral fubftitutions 
 and adulterations pra<£lifed in rela- 
 tion to them ; as alfo the beft means 
 of detecting fuch pradices. 
 
 SECTION L 
 
 Of the preparation of thofe medicines + 
 wheref aline fubjlances make thewhole^ 
 or principal part of thefubjeB. 
 
 Preparation of fpirit of hart/horn. 
 
 LET pieces of hartfhorn be diftilled, with 
 a fire gradually augmented, almoft to 
 the greateft degree. Spirit, fait, and oil will 
 arife : and, the oil being taken from them, let 
 the fpirit, and fait, be mixt together again ; and 
 diftilled with a very gentle heat, and they will 
 both rife purer : which operation being feve- 
 ral times cautioufly repeated, and a proper 
 part of the fait taken away to be referved for 
 fublimation, the fpirit will become limpid as 
 water, and have a grateful fmell. 
 
 G 3 Note. 
 
86 Chemical Preparations. 
 
 Note. 
 
 Spirit of hartfhorn is one of the capital ar- 
 tittes of the chemical pharmacy, and has un- 
 dergone a greater revolution, in its price, and 
 manner of preparation, than any medicine 
 whatever. A few years ago, the loweft rate 
 it was fold for, in the mod wholefale way, was 
 half a crown, or three fhillings per pound : it 
 has fince been reduced to the low price of five 
 pence or a groat ; at which rate, a great part 
 of the confumption has been fupplied, by the 
 preparers, to the wholefale dealers. This is 
 done by an intire fubftitution of other volatile 
 Spirits, diftilled from fubftances much cheaper 
 than hartfhorn : and by the treating even thefe 
 in fuch a manner as difguifes their real ftrength j 
 and makes even very weak pafs for extreme 
 good fpirit of hartfhorn, though fold as at this 
 exceflive low price : whereas genuine fpirit of 
 hartfhorn, prepared as the above procefs directs, 
 can never be afforded with reafonable profit for 
 lefs than two fhillings per pound. 
 
 It is not, however, eflential, that this medi- 
 cine fhould be prepared from horn \ but rather 
 improper : for volatile fpirits, obtained from this 
 fubftance, however often they may be recti- 
 fied, at leaft within any moderate compafs, are 
 apt to grow brown, foul, and foetid : fothat, 
 if kept for any length of time, they become 
 naufeous and unfightly : whereas, if diftilled 
 from bones properly prepared, they require 
 
 much 
 
Chemical Preparations. 87 
 
 much lefs rectification > are more palatable and 
 grateful to the ftomach ; and will retain their 
 limpid and colourlefs appearance for a confi- 
 derable duration, a quality very valuable to apo- 
 thecaries, efpecially thofe in the country, who 
 cannot be continually renewing their ftock. 
 
 The redundance of, and unfavourable qua- 
 lity in, the burnt oil of horns, to which this un- 
 fitnefs to produce good volatile fpirits is owing, 
 arife from the great quantity of the animal 
 gluten which all corneous fubftances contain :. 
 this gluten abounding in all parts of animals 
 in proportion to their tenacity; of which indeed 
 it is the caufe : and being, in faCt, nothing but 
 oil mutually attracting and attracted by the earth, 
 which constitutes the folid bafis of the parts. 
 
 If we admit all volatile falts to be the fame ; 
 and confider, that this compound, we call fpirit 
 of hartfhorn, confifts of water, volatile fait, and 
 diftilled animal oil ; we fhall fee, that, as no 
 difference can lie in the volatile falts, or wa- 
 ter ; it muft, if there be any difference at all 
 betwixt this fpirit, and that diftilled from any 
 other animal fubftance, be in the oil only. 
 
 Now all diftilled oils of animal fubftances, 
 being likewife of the fame nature ; except that, 
 by the aCtion of the fire, fome are higher ex- 
 alted, and gaining a more ethereal nature, be- 
 come lefs liable to putrefaction ; while others, 
 being lefs changed from their original groffer 
 ftate, retain fome tendency to putrefy \ it muft 
 appear, that there can be no difference in vola- 
 tile fpirits, but in their being charged, in a 
 
 G 4 greater 
 
88 Chemical Preparations. 
 
 greater or lefs proportion, with oils that vary- 
 Only in their exaltation, or approach to the ethe- 
 real ftate ; in the greater degree of which, con- 
 lifts their medicinal excellence : as may be 
 eafiiy granted, when it is confidered, in what in- 
 tention they are taken. If, therefore, it fhould 
 be manifeft, from experiment, that volatile 
 fpirit, extracted from prepared bones, or any 
 other animal fubftance, contains a more ethe- 
 real oil, than fpirit drawn from hartfhorn $ 
 it muft confequently be concluded to be a 
 more efficacious medicine, as well as a much 
 more gratefid and convenient one, on the ac- 
 count above mentioned. 
 
 Dr. P, in his notes on this article, in the 
 tranflation of, the College-Difpenfatory, feems 
 to think, this fpirit fhould be diverted as much 
 as poffible of the oil. For he places the per- 
 fection of the preparation in the number of 
 testifications : and on this principle, half a 
 guinea an ounce has been charged for fome 
 quantities, fuppofed to be thus improved. But 
 certainly there are limits to the proportion of 
 oil that fhould be thus feparated from the 
 fpirit : for if no oil were neceflary to the con- 
 fluence of the medicine -, but that a pure vo- 
 latile fait and water made its proper contents ; 
 it might be much better prepared, by making 
 a folution of volatile fait of fal Ammonia- 
 cum in water ; or diftilling fuch a fpirit 
 from a folution of fal Ammoniacum with 
 fait of tartar : but the true compofition 
 of it, is not, from volatile falts and water a- 
 
 lone ; 
 
Chemical Preparations. 89 
 
 lone ; but from thefe with the addition of 
 ethereal animal oil ; which makes, with theo- 
 thers a volatile fapo : the cil being evidently an. 
 ingredient, correfpondent to the intention, e- 
 qually with the volatile fait ; as may be gathered 
 from its affinity with other ethereal oils, as of 
 amber, or the aromatic vegetables, &c. Which- 
 ever of thefe notions we adopt, the fpirit of 
 bones feems ftill preferable to thofe of horn : 
 and we fhall principally inquire, how that can 
 be beft and cheapeft prepared : but for the 
 fake of thofe, who adhere to the old faith, as to 
 the fuperiority of the true fpirit of hartfhorn, to 
 other volatile fpirits diftilled from other animals, 
 or parts of them, I fhall firft make fome obfer- 
 vations on the regular procefs above given, and 
 the beft manner of performing it : pointing out, 
 aifo, the defedts of the apparatus generally ufed; 
 and (hewing how they may be beft amended. 
 
 The pots, in which this diftillation is made, 
 are much too fmall ; being, in general, made 
 to contain only three quarters of a hundred 
 weight of the horn : whereas, with the fame 
 fire and trouble, double or treble the quantity- 
 might be diftilled together, in larger pots. The 
 reafon for this unprofitable manner of work- 
 ing, has been the difficulty found in forming 
 a proper apparatus, for condenfing the diftilled 
 vapour, when raifed in a greater quantity than 
 three quarters of a hundred, or a hundred 
 weight of materials would afford. The moft 
 general way has been to ufe, as a refrigeratory, 
 only a feries of glafs allodials luted together, 
 
 and 
 
90 Chemical Preparations. 
 
 and terminating in a glafs receiver : but later 
 improvements have introduced the ufe of a long 
 tin tube, joined to the pot by one or two al- 
 lodials placed next the pot, pafling into a large 
 earthen or ftone jar, made clofe at the top, 
 and venting itfelf again by another tube of the 
 fame kind, terminating either in another fuch 
 jar, or a large glafs receiver. 
 
 This has been found much preferable to the 
 firft method, of ufing glafs allodials alone ; 
 but both of them are far inferior to that de- 
 fcribed in the next procefs. 
 
 By the beft of thefe methods, fix or eight 
 days are required, from the charging the pot, 
 to the finifhing the operation : for a confidera- 
 ble time is taken up, for the drying the lute ; 
 which is with much trouble laid on, and re- 
 paired, at fo many different junctures : and, 
 when this tedious part of the work is finifhed, 
 the fire muft be very well regulated, other- 
 wife the lute will be blown off, the ftench be- 
 come intolerable, and a very great wafte made 
 of the produce of the operation ; indeed a con- 
 fiderable wafte, and a very bad fmell, will al- 
 ways attend this manner of working, even 
 when beft managed. There is indeed a way, 
 that has been hitherto overlooked, from the 
 almoft univerfal ignorance in principles, of per- 
 fohs concerned in thefe operations, of prevent- 
 ing greatly the fmell and wafte with the worft 
 apparatus. For the force on the lute, being, in 
 a great degree, owing to the air generated in 
 that anaiyfis, which the fire makes of the ele- 
 ments 
 
Chemical Preparations. 91 
 merits that compofe the fubftances diftilled ; 
 which air being incondenfible, as well as highly 
 elaftic, muft fome where find a vent, as its quan- 
 tity augments j this air {training the lute, cracks 
 and opens it - y and preiling out through thefe 
 cracks or openings, drives with it, likewife, the 
 condenlible part of the vapour, efpecially a- 
 bout the head, and firft allodial, which are re- 
 plete with fuch vapour 5 becaufe the heat pre- 
 vents almoft any condenfation from being per- 
 formed there. If, therefore, a proper vent 
 fhould be made in the receiver, or fome diftant 
 part of the condenfing veffels ; by means of 
 which, the lute may be kept free from its ef- 
 forts, and remain intire : the rivus of air 
 would pafs forwards to the vent of the ex- 
 tremity of the furface, and drive along with 
 it the condenfible vapour that forms the di- 
 ftilled fpirit ; which thus coming, in its paf- 
 fage, in contad: with the refrigerating furface 
 of the veffels, will be for the moil part con- 
 denfed, and not blown out through the cracks, 
 otherwife produced in the lute. This vent 
 may be likewife carried into a fmall tin pipe, 
 communicating with the chimney, or afh- 
 hole ; by which means, both the elaboratory, 
 and places contiguous, may be kept free, in a 
 great degree, from this troublefome fmell. 
 
 It would be much better, however, in all 
 cafes, to ufe the worm, as a refrigeratory, in 
 the diftillation of hartfhorn ; according to the 
 directions given below : for though the fait 
 .would not be obtained, in this part of the pro- 
 
 cefs, 
 
92 Chemical Preparations. 
 
 cefs, in fuch proportion as when allodials are 
 ufed : yet a confiderable quantity may be taken 
 out of the receiver, ufed in fuch diftillation 5 
 and what more may be wanted, may be got 
 out of the receivers, ufed in the re&ification ; 
 if they be taken off before the fpirit begins to 
 come over and wafh the fait off the fides : and 
 the fait procured by thefe methods, will be 
 much freer from oil; and, confequently, much 
 lefs troublefome in rectifying, than that taken 
 out of the allodials : it being exactly the fame, 
 in the refult, which way it is feparated from 
 the diftilled fpirit ; as there will the fame pro- 
 portionable quantity remain in it after what is 
 taken. 
 
 Another defeCt in the common manage- 
 ment of the genuine fpirit of hartfhorn, is, 
 the want of a more commodious method of 
 feparating, immediately after the diftillation, 
 the foul oil, which comes over with the fpirit 
 and fait, and caufes a confiderable wafte, when 
 taken out by the methods now ufed : and, 
 which not being very efficacious in freeing it 
 from the oil, occafion the fpirit to be injured 
 by being kept too long commixt with what is 
 left floating upon it. This may be beft reme- 
 died by employing the tritorium defcribed in 
 the introduction, in the manner below ordered; 
 and treating the fpirit according to the fubfe- 
 quent directions there laid down. 
 
 In the procefs of the college above given, 
 the fait is ordered to be rectified along with the 
 fpirit, before its being taken away to be fub- 
 
 limed; 
 
Chemical Preparations. 93 
 
 limed; which is one of the moft effectual 
 methods of giving it fome degree of purity. 
 But the more common way, is to feparate it 
 from the fpirit, immediately after the diftilla- 
 tion from the materials -, by which a confiderablc 
 delay is avoided in the rectification of the fpirit. 
 The number of rectifications intimated to 
 be neceflary in this procefs, are likewife fre- 
 quently curtailed : though, in order to the 
 making the genuine fpirit keep tolerably, there 
 ought to be four, and thefe performed at fome 
 diftance of time from each other ; the oil 
 fwimming on the furfaceof the fluid being care- 
 fully feparated after each : for fewer rectificati- 
 ons, performed at intervals of fome length, 
 will render the fpirit more pure than a greater 
 number, quicker repeated : as the oil can be 
 much more copioufly feparated, from the fpirit, 
 by rectification, after the natural feparation of 
 it by its own tendency, which (hews itfelf by 
 a turbidnefs and fediment, than, while they 
 remain more perfectly united, as in the limpid 
 ftate they are found to be, for fome time after 
 each rectification. 
 
 Method of making fpirit of hart/horn, ffiitious, 
 with refpeSi to the materials , butperfe£l> with 
 regard to the qualities correfpondent to the in- 
 tention of medicine. 
 
 Take any quantity of the bones, from 
 whence the fat has been extracted, by thofe 
 
 who 
 
94 Chemical Preparations. 
 who colleft them for that purpofe : diftill 
 them, and re&ify the fait and fpirit together, 
 taking out a proper quantity of fait, which 
 will rife before the fpirit, by changing the 
 retort before the fait be melted by the fpirit : 
 re&ify the fpirit twice more 4 and, after 
 keeping it for fome time, filter it through 
 paper. 
 
 Note. 
 
 Thefe materials, both from their own nature, 
 and the previous preparation in the freeing them 
 from all oily fubftances, by the long boiling, 
 pradtifed by the people, who colleft them, are 
 the beft and cheapeft materials, from whence 
 this fpirit could poflibly be drawn : they may 
 be purchafed, in London, at five fhillings per 
 ton ; and they afford a very pure fpirit, with 
 very little trouble, as I have before men- 
 tioned. 
 
 The diftillation fhould be performed in the 
 pot, with the worm and other parts of the 
 apparatus, as defcribed p. 35, into which, be- 
 ing put, and the cover placed on it ; which, 
 without lute, will make a clofe joint, the diftil- 
 lation may be immediately begun 5 and will 
 be over, with proper management, in fixteen 
 or eighteen hours. 
 
 The 
 
Chemical Preparations. 93 
 
 The end of the bending pipe, added to the 
 end of the worm, for that purpofe, muft be 
 let into the neck of a large receiver placed 
 under it ; and the tin pipe, for carrying off 
 the fmell, fhould alfo have its bending end put 
 into the neck of the receiver -, and the remain- 
 ing opening of the mouth may be made good, 
 by fome moift, but ftiff, clay. 
 
 When the receiver appears of a proper ful- 
 nefs, it fhould be taken away; and another put 
 in its ftead, in the fame manner as the firft ; 
 and this fhould be repeated as often as they fill. 
 The receivers fhould be emptied, by means of 
 a tin funnel, into the tin or pewter tritorium 
 defcribed p. 30 ; and the crude fpirit kept 
 there till it be wanted for rectification 3 or, if 
 the tritorium will not contain all that may 
 happen to be made, this fpirit may be drawn 
 off, from it, into a proper bottle, to make room 
 for the frefh, through the lower tube, which 
 alone muft be ufed for this purpofe ; the upper 
 one being defigned for drawing off the oil, which 
 will float on the fpirit, and may be eafily taken 
 away from it, by this method, when there is 
 a proper quantity in the tritorium, and the 
 ipirit raifes it to a proper height. 
 
 If, as will fometimes happen towards the 
 end of the diftillation, the worm fhould be fo 
 choaked up with the fait, arifing along with 
 the fpirit, that the paffage of the vapours may 
 be obftrudted, which may be perceived by the 
 appearance of the fmoke through the juncture 
 
 of 
 
96 Chemical Preparations. 
 
 of the cover and pot, the ftopper fhould be 
 immediately taken out of the fmall pipe in the 
 upper part of the worm 5 and, a fmall tin 
 funnel being put in it, water fhould be poured 
 into the worm ; which will force its way, by 
 melting the concreted fait : and this muft be 
 repeated till the paffage appear free, by the 
 running of the water into the receiver with- 
 out any fign of obftruftion. 
 
 The whole worm muft be, likewife, filled 
 with water, by the fame means, as foon as 
 the operation is finifhed : the end of the fmall 
 bending pipe, at the extremity of the worm, 
 being firft ftopt with a cork : and this water 
 may be left in the worm, till the ufe of the 
 pot is again wanted ; when it muft be taken 
 out, and put into the tritorium along with the 
 other fpirit, which it will nearly equal in 
 ftrength, by having diffolved the fait con- 
 creted in the worm, according to the inten- 
 tion of its being put there. This fhould be 
 carefully remembered : for, on the clearing 
 the worm, by this means, of the fait, which 
 is neceffarily collected there, each diftillation, 
 depends the practicability of its ufe. 
 
 After the firft, and every other diftillation, 
 the oil fwimming on the fpirit fhould be care- 
 fully feparated from it ; which may be done, 
 by paffing this fpirit through a large glafs fun- 
 nel, in the bottom of which, a piece of cotton 
 is fo placed, that the fluid palling through gra- 
 dually, the oil may be kept from following the 
 2 fpirifc 
 
Chemical Preparations. 97 
 
 fpirit, by removing the funnel after the fpirit is 
 gone through it. 
 
 The oil feparated, in the feeond and third 
 rectifications, fhould be put into a phial 5 and 
 preferved ; in order to make the fictitious fait 
 of hartlfhorn. 
 
 After the laft re&ification, the fpirit fhould 
 be filtered, by means of the cullender, &c. 
 defcribed p. 32 : and, if it be kept a confi- 
 derable time, the filtering may be repeated 
 before it be fold, if the quantity be confidera- 
 ble. 
 
 This volatile fpirit is, with regard to the 
 medicinal intentions, equal in all refpedls, 
 and in fome fuperior, to the true fpirit of 
 hartfhorn ; for which at prefent it is gene- 
 rally fold; as is fometimes, likewife, the fol- 
 lowing kind. 
 
 Compendious preparation of a volatile fpirit*, 
 refembling the above ^ and the true fpirit of 
 hart/horn. 
 
 Take volatile fpirit of fal Ammoniacum, 
 obtained by ehalk, or fait of tartar, but with- 
 out lime, one gallon $ or two pounds of fal 
 Ammoniacum , and the fame quantity of dry 
 pearl afhes, may be ufed, with a gallon of 
 water, inftead of the fpirit 5. to this add, of 
 the crude fpirit of hartfhorn, or bones, half 
 
 H a 
 
93 Chemical Preparations. 
 a gallon : diftill them, as in the rectifica- 
 tion of fpirit of hartfhorn, and draw off 
 the fpirit, while it comes over of a due 
 ftrength : filter it, after it has been kept 
 fome days. 
 
 Note. 
 
 This will in all refpe&s referable perfect 
 fpirit of hartfhorn, as prepared by thefirft pro- 
 cefs ; but if it be made of the crude fpirit of 
 hartfhorn, like the true fpirit, it will be apt to 
 turn foul and foetid. That made with the fpirit 
 of bones will keep much longer ; but not fo 
 well as the produce of the former procefs. 
 
 However this fubflitution may refemble the 
 true kind of fpirit of hartfhorn, or that drawn 
 from bones, it will be inferior with regard to 
 the medicinal qualities ; becaufe, though it 
 will appear equally replete with oil, yet it will 
 not contain fo great a quantity ; and what it 
 may contain will be of a grofler, and lefs ethe- 
 real nature, as its tendency to grow fostid, and 
 foul, evinces ; and, if kept anytime, it will be- 
 come naufeous, and be apt to rife on the 
 ftomach, like the genuine fpirit of hartfhorn. 
 
 This fpirit is, however, much lefs exception- 
 able than another kind too commonly impofed 
 on the public ; which is prepared by means of 
 ..quicklime, after the following manner. 
 
 Sophijli cation 
 
Chemical Preparations. 99 
 
 Svphiftkation of f pint of hartjhorn, by means 
 if quicklime. 
 
 To a gallon of crude fpirit of hartfhorn, 
 or bones, add one pound of quicklime* 
 either at the firft, or any fubfequent rec- 
 tification ; draw off the fpirit, and treat it 
 as the genuine. 
 
 Note. 
 
 This is, by much, the worft fophifHcation 
 of fpirit of hartfhorn $ and cannot be too much 
 guarded againft, by all, who are concerned in 
 the fale, or ufe, of this medicine. When 
 indeed it is drawn off with a due proportion of 
 ftrength ; and ufed only to fmell to, its ex- 
 traordinary pungency renders it very fit for the 
 purpofe : though this end may be equally well 
 anfwered by volatile fpirit of fal Ammonia- 
 cum, which is almoft every where to be had 
 prepared in the fame manner : but when this 
 kind is drawn off only of the apparent ftrength 
 of the true fpirit of hartfhorn, and impofed, in its 
 place, for internal ufe, it is a confiderable fraud. 
 For it is neceffarily very defective, in the quan- 
 tity of volatile fait ; in which the principal effi- 
 cacy of this medicine confifts : the end of ufing 
 the lime being to increafe the pungency ; and 
 make the fpirit, drawn off, much weaker, feem 
 equally flrong, with that impregnated with the 
 
 H 2 due 
 
ioo Chemical Preparations. 
 
 due proportion of volatile fait; and by this 
 means, to increafe the quantity. Which delu- 
 lion occafions, therefore, only a part of the 
 intended dofe to be virtually taken. 
 
 If we paid an implicit deference to the au- 
 thority of the college, there would be anQther 
 - reafon againft this fophiftication : for they have 
 condemned the ufe of lime with volatile falts, 
 as rendering them noxioufly acrimonious, and 
 corrofive. But, if there were any truth in this 
 principle, it muft hold good, alfo, with refped: 
 to fixt alkaline falts -, and yet we fee, not only 
 experience, but even the opinion of this great 
 body itfelf, in the fame work, affaire us of the 
 contrary. Nor does it indeed appear from fadts, 
 that there is any perfectly diffolvable body, 
 which can injure by its acrimony, when fuffi- 
 ciently diluted. 
 
 This impofition of the fpirit of hartfhorn, or 
 bones, aftuated with quick-lime, inftead of the 
 genuine, is, however, fuppofed to be eafily 
 detedtible, by the following means. 
 
 A method ufedfor detecting the fpirit of hartf- 
 horn fophijlicated with quick-lime. 
 
 Add ftrong fpirit of wine to the fufpefted 
 fpirit 3 and if it do not foon give the ap- 
 pearance of little fparkling bodies, fwim- 
 ming in the fluid, and afterwards fubfiding 
 to the bottom, it may be concluded to be fo- 
 
 phifticated, 
 
Chemical Preparations. ioi 
 
 phifticated, with quicklime, provided, by the 
 pungency, it appear to be of due ftrength. 
 
 Note. 
 
 The principle, on which the above proof is 
 grounded, is this. If fpirit of wine be added 
 to water, impregnate with volatile falts, in the 
 proportion of good fpirit of hartfhorn, it will 
 deftroy, in a certain degree, the difTolving 
 power of the water ; and, confequently, a part 
 of the fait, before diflblved, will fhoot into 
 fmall chryftals, which fhew themfelves, firft 
 in the form of little fparkling bodies, and after- 
 wards in that of a fhining powder at the bot- 
 tom of the phials, or other veflel, in which the 
 mixture is contained. But, if the fpirit be fb- 
 phifticated with quick-lime, this will not hap- 
 pen, from two reafons -> firft, becaufe quicklime 
 changes in fuch manner, the volatile falts, that 
 they become fo extremely foluble, the water can 
 fcarcely be faturated with them, in any propor- 
 tion ; or made to fhoot them in chryftals, 
 tho' they abound in any quantity whatever : 
 fecondly, becaufe the fpirit, fo fophifticated, 
 does not contain a fufficient quantity of falts, 
 to occafion the chryftallization of them from 
 the weakning the foluble power of the water 
 by the fpirit of wine, even though their na- 
 ture was not changed by the atftion of the 
 quicklime. It may therefore be taken as a 
 certain criterion, that the fpirit is fophifticated 
 
 H 3 with 
 
102 Chemical Preparations. 
 
 with quick-lime, if no fuch appearance follow, 
 the admixture of the fpirit : but this method 
 of trial is neverthelefs fo far defective, that no 
 inference can be drawn from it, with certainty, 
 of the fpirit's being really genuine, notwith- 
 ftanding a very plentiful chryftallization fhould 
 $nfue : though it has been hitherto looked on, 
 as equally conclufive as to that point alfo. But 
 a method has been contrived of preparing the 
 Spirit in fuch manner, that though the quan- 
 tity of volatile fait be greatly deficient, and the 
 appearance of due ftrength be procured by the 
 help of quick-lime ; yet on this trial, with fpirit 
 of wine, the refult will be the fame, as in the 
 fpirit of hartfhorn, where no quick-lime was 
 ufed; and the fmall chryftals will be produced, 
 in fuch abundance, as to induce the opinion of 
 its being extraordinarily good, if this experi- 
 ment were a fufficient teft. I have feen a quan- 
 tity, not lefs than five hundred weight, treated 
 in this manner, which pafled the hands of per- 
 fons, who thought themfelves very fkilful in 
 matters of this kind : and I make no doubt 
 this additional fraud would be more frequently 
 pradtifed, if known -, efpecially, as it increafes 
 the weight of the fpirit at a very fmall expence. 
 I fhall therefore omit the teaching the method 
 of effecting it 5 and inftead of that, give a fure 
 way of difcovering where it is pradtifed, and 
 of determining, moreover, in all cafes, whether 
 the fpirit, when it appears of due ftrength, be 
 prepared with lime, or not, 
 
 A 
 
Chemical Preparations. 103 
 
 A more certain method of dtfcovering, when 
 fpirit of hartjhorn^ or other volatile fpirit ; , 
 isfophijlicated with quick-lime. 
 
 Mix ftrong fpirit of wine with the volatile 
 fpirit fufpe£fced ; and, if a chryftalline pow- 
 der be produced, let it fubfide till the fluid 
 can be poured off; and having put it into a 
 fpoon, hold it near the fire, or over the flame 
 of a candle : if the powder exhale and dis- 
 appear, it may be concluded, that the fpirit 
 is not prepared with lime, but contains a 
 due proportion of volatile fait -, but if it 
 remain after it has undergone, even, a 
 gentle degree of heat, it may be taken for 
 granted, that not only the ufe of quick-lime, 
 but other elufive methods have been prac- 
 
 tifed. 
 
 I 
 
 Note. 
 
 I fhall not explain the principles, on which 
 this trial is founded, becaufe they will be ob- 
 vious to perfons, who are any way verfed in 
 thefe matters, and a farther elucidation would 
 lead others into the knowledge of the art it is 
 intended to explode. But whoever purchafes 
 any gonfiderable quantity of fpirit of hartfhorn, 
 
 H 4 would 
 
104 Chemical Preparations, 
 would do well to prove it in this manner - y and 
 may be affured, if it appear of due ftrength by 
 its pungency to the noie, and ftand this teft, 
 that it is not fophifticated with lime ; but pro- 
 perly replete with volatile falts. 
 
 Salt of hartjhorn. 
 
 Let the fait be taken out of the receivers, 
 after the diftillation, or out of the retorts, 
 after the redtification, before it be melted 
 by the fpirit, which will rife afterwards ; and 
 fublimed, firft with an equal weight of chalk ; 
 and afterwards with a little re£tified fpirit of 
 wine. 
 
 Note. 
 
 This is the procefs given by the college for 
 the preparation of this medicine. The fame 
 may be done with refpedt to the volatile fait, 
 obtained from bones, which will keep its white 
 colour longer, and be much lefs fubjedt to grow 
 foetid, than that extrafted from horn. 
 
 The quantity of chalk, here directed, is 
 much greater than is requifite to abforb the oil, 
 and prevent its rifing with the fait ; for which 
 reafon only it is added : half the quantity, or 
 lefs, will anfwer the end equally well. 
 
 The fpirit of wine, which is defigned to 
 combine with, and wafh down, the oil from 
 
 the 
 
Chemical Preparations. 105 
 
 the fait, does not, on experiment, anfwer the 
 purpofe, in a proportion equivalent to the 
 inconvenience its elaftic vapour, joined to that 
 of the volatile fait, produces, during the whole 
 operation, by forcing the lute : and it will be 
 found, on trying both methods, that the fub- 
 limation will fucceed, on the whole, better 
 without it. 
 
 Thefublimation of the fait of hartfhornisbeft 
 performed in a retort, with a fmall receiver ; 
 the neck of the retort being fhort and wide. 
 
 After the fait of hartfhorn, or even that of 
 bones, have been purified, in the beft manner 
 they can, by repeated fublimation, it will foon 
 grow brown and foetid, by keeping ; which is 
 a great inconvenience to thofe who fell it, and 
 have not a quick demand. The following 
 fiftitious kind has been, therefore, fubftituted 
 for it $ being not only free from this incom- 
 modious quality of changing colour; but, alfo, 
 prepared with much lefs trouble and expence. 
 
 FiBitious fait of hartfloom, the fame with the 
 genuine in all other qualities -, and not fub- 
 je£l to change colour > or grow foetid. 
 
 Take fix pounds of the volatile fait of 
 fal Ammoniacum ; add to it half a pound 
 pf chalk, mixt with two ounces of the oil 
 taken off the fpirit of bones^ in the re6lifi- 
 
 cation* 
 
106 Chemical Preparations. 
 cation, as dire&ed p. 97 ; fublime them to- 
 gether 5 and feparate the white part after the 
 fublimation, from that which appears brown 3 
 the latter being referved for another fubli- 
 mation, with a frefh quantity. 
 
 Note. 
 
 In making the volatile fait of the fal Am- 
 moniacum, a part of it will neceflarily arife 
 foul, as we fhall fee below : fuch foul part 
 will very well ferve for this purpofe. 
 
 If it be more convenient, infiead of taking the 
 volatile fait already made, to conjoin the making 
 it, and the converting it into the fait of hartf- 
 horn, into one operation, the crude fal Am- 
 moniacum, and proper quantity of chalk, may 
 be ufed according to the procefs below given : 
 and, in this cafe, it is beft to mix the oil with 
 chalk into a ftiff pafic ; and, having formed the 
 mixture into balls, to put them into the retort 
 after the other ingredients, that they may lie 
 out of the reach of the ftronger heat, which 
 would occafion the oil to rife before the greateft 
 part of the fait. 
 
 The fait, fo prepared, is indiftinguifhable 
 from the genuine fait of hartfhorn, by any other 
 means, than keeping it till the continuance of 
 its white colour (hall fhew the difference : and, 
 notwithftanding, I have given it the name of fic- 
 titious, it is in reality the fame, with the fait ob- 
 tained 
 
Chemical Preparations. 107 
 
 tained by the regular procefs ; except that the oil is 
 of a purer, and more ethereal nature, than what 
 is found in the other : on which account, this 
 is certainly preferable, for other reafons, as well 
 as its maintaining its whitenefs, and not becom- 
 ing foetid, Since, if we allow all volatile alka- 
 line falts, to be the fame, this muft appear a 
 better medicine, from the qualities of the oil 
 it contains; and recommends itfelf ftill further 
 by being of a much more cheap and eafy pre~ 
 paration than the genuine. 
 
 Calcined bartjkorn. 
 
 Let pieces of hartfhorn, or the coal which 
 comes out of the pot after the diftillation 
 of the fpirit of hartfhorn, be burnt in an 
 open fire, till they become perfectly white : 
 and, then, let them be levigated as other 
 earthy, or teftaceous bodies. 
 
 Note. 
 
 The college of London have dire&ed this 
 to be done in a potters furnace : and for thofe, 
 who have not occaiion to calcine fuch quan- 
 tities, as may anfwer the expence of a proper 
 furnace in their own elaboratory, the fending 
 the materials to the potters, tobacco-pipe- 
 makers, or other fuch perfons, who have very 
 ftrong fires fdr other purpofes, will be the 
 cheapeft and eafieft method, 
 
 3 FiSiitious 
 
ic8 Chemical Preparations. 
 
 FiBitious calcined hartjhorn. 
 
 Let the coal of the bones, which re- 
 mains, in the pot, after the extraction of 
 the volatile fpirit from them, be treated in 
 the fame manner as that of hartfhorn. 
 
 Note. 
 
 This fubftitution is very frequently prac- 
 tifed ; and, if the bones be perfectly calcined, 
 the earth will be indiftinguifhable from that of 
 the hartfhorn : being in fad: abfolutely the fame 
 fubftance, This, therefore, is a fraud produc- 
 tive of very little mifchief ; and may be per- 
 mitted where any fuch are allowed. 
 
 It is, however, much more difficult, from their 
 texture, to give the bones a perfeft calcination 
 than the horn : and it is, therefore, proper to 
 break the coal of them, which is ufed for this 
 purpofe, dnto very fmall bits ; which much 
 facilitates the operation. 
 
 Volatile fait of fal Ammoniacum. 
 
 Take of the pureft chalk, two pounds, 
 fal Ammoniacum one pound, fublime them 
 in a retort, with a ftrong fire. 
 
 Note. 
 
Chemical Preparations, 109 
 
 Note. 
 
 This is the procefs of the London-college, 
 and the common pradice : but the quantity of 
 chalk is much too great ; filling the retort un- 
 neeeflarily, and adding, in fome degree, to the 
 foulnefs of the fait ; if the chalk, as happens 
 very frequently, contain any impurities. The 
 following is therefore a much better propor- 
 tion of the ingredients : and the directions be- 
 low given for the conduct of the operation, if 
 obferved, will produce a whiter fait, and with 
 much lefs expence and trouble, than the me- 
 thods commonly pra&ifed. 
 
 Improved procefs , for the making the volatile 
 fait of fal Ammoniacum. 
 
 Take the whiteft fal Ammoniacum, dry 
 it well while in large pieces, and pick out 
 from it, and fcrape off every part, which 
 appears the leaft difcoloured. Then take 
 the cleaneft chalk j and dry it thoroughly, 
 by heating it as hot as boiling water, but 
 not hotter : powder it well, and dry it again : 
 mix the fal Ammoniacum and the chalk, 
 while both are in this dry flate, in the pro- 
 portion of five parts of chalk, to four of 
 
 the 
 
no Chemical Preparations* 
 the fal Ammoniacum : put them into a re-* 
 tort, with a thick (hort neck, and the orifice 
 cut very wide ; fit to it a fmall receiver, with 
 a long neck -, and lute them well together. 
 Then put them into a fand~pot $ and fin 
 blime the fait, very gradually ; never fuf- 
 fering the lower part of the receiver to grow 
 very hot. Let the fire, however, be raifed 
 to a ftrong heat at the latter part of the 
 operation. When the retort and receiver 
 are grown cold, break the receiver, and fe- 
 parate fo much of the fait as appears white 
 and pure, from the difcoloured ; and break- 
 ing it into lumps, preferve it carefully from 
 exhaling, which will dull the tranfparent 
 appearance. The lefs fightly, and foul, parts, 
 may be ufed for the making the fpiritus 
 volatilis oleofus ; or fi&itious fait of hartf- 
 horn ; or purified by refublimation, if that 
 be more convenient* 
 
 Note. 
 
 By this method of diminishing the quantity 
 of chalk, ufing only fuch fal Ammoniacum 
 as is clean, and employing a fmall receiver, 
 the neceffity of a fecond fublimation is taken 
 
 away : 
 
Chemical PsLfitARATioKs. i i i 
 
 away : for the purity of the fal Ammoniacum 
 will occaiion a confiderable quantity of the vo- 
 latile fait to be pure alio : and render the re- 
 torts capable of fubliming a greater quantity of 
 the fait, by diminifhing the quantity of chalk ; 
 and the ufing at the fame time a fmall re- 
 ceiver, will caufe the cake of the fublimed falts 
 to be of a due thicknefs ; which it otherwife 
 cannot be made, without putting the produce 
 of two or three of thefe operations together, 
 and fubliming afrefh. 
 
 The fcrapings, or foul parts, picked out of the 
 fal Ammoniacum, need not, in the leaft, in- 
 hance the expence : for they may be ufed, for 
 making the volatile fpirits, or any other fuch 
 purpofe : neither will the foul parts of the fu- 
 blimed volatile fait be in the leaft a lofs, for they 
 may be very profitably employed alfo, for the 
 purpofes abovementioned. 
 
 Great care fhould be taken, if the powdered 
 chalk and fal Ammoniacum be kept after they 
 are reduced to that ftate, either together, or fe- 
 parately, not to fuffer the air to have any accefs 
 to them : for they will immediately attract 
 moifture, which is very detrimental to this 
 operation; as a- very fmall quantity is apt to 
 melt down the fait from the fides of the re- 
 ceiver into the bottom, and diminifh the thick- 
 jiefs of the fublimed cake, on which the pro- 
 duce of the faleable fait depends. 
 
 Much caution fhould be likewife ufed, in 
 the management of the fire : for, if it be pre- 
 cipitated, not only a great rifque is run of burft- 
 
 ing 
 
ii2 Chemical Preparations. 
 
 ing the retort, or receiver; but, the fait, being 
 in too hot a fiate, to form on the fides, will 
 flow cfowri to the bottom of the receiver, and 
 produce the difad vantage before mentioned. 
 
 A cake of crude fal Ammoniacum will 
 fometimes be found on the top of the chalk, 
 after the fublimation ; as likewife in the neck 
 of the retort. This may be alfo ufed for 
 making the volatile fpirit, and the fal Ammo- 
 niacum, as the being mixt with the chalk will 
 not in the leaft injure it for that purpofe- 
 
 Volatile fpirit of fal Ammoniacum 'with fixt 
 alkaline fait. 
 
 Take of any fixt alkaline fait, one pound 
 and half, fal Ammoniacum, one pound, 
 water, four pints : with a gentle fire, diftill 
 off two pints. 
 
 Note. 
 
 This is the procefs of the London-College ; 
 in which the quantities feem very ill adjufted : 
 for one pound of dry pure, fixt, alkaline fait is 
 more than* Sufficient, to difpoflefs the volatile 
 fait of the fal Ammoniacum of its acid fpirit. 
 The quantity of fluid drawn off is likewife 
 very fmall, in proportion to the quantity of 
 fait : for volatile fpirit is extremely ftrong, 
 when one fourth part of it is fait. This fait 
 
 may 
 
Chemical Preparations. 113 
 
 may be prepared genuinly, and at a moderate 
 expence, in the following manner. 
 
 Cheaper method of preparing the volatile fpirit . 
 of fal Ammoniacum with fixt alkaline fait \ 
 
 Take of fal Ammoniacum, and pearl 
 afhes, equal parts ; add to them about five 
 times their weight of water 5 put them into 
 the tin alembic defcribed p. 40 ; and fix two 
 receivers to the two arms ; place it in the 
 fand-bath ; and diftill off the fpirit, while 
 it continues to coine off ftrong : when it 
 appears weaker, change the receivers, and 
 draw off the remainder fo long as the fluid 
 partakes of any fmeli of the volatile falts. 
 Put by the ftrbng for ufe ; keeping the weak, 
 to be added to the water in the next opera- 
 tion, of the fame kind ; or ufe it along with 
 other volatile fpirit, or fait, in the making 
 the fpiritus volatilis aromaticus ; or for any 
 fuch purpofe* 
 
 Note. 
 
 The fcrapings of the fal 'Ammoniacum, de- 
 figned for the volatile fait, may be employed 
 for this purpofe : or the foul part of the vola- 
 
 I tile 
 
U4 Chemical Preparations* 
 
 tile fait itfelf, diffolved, may be added to this 
 fpirit, when there is any convenience in fo do- 
 ing ; but the folution muft be firffc filtered, if it 
 appear in the leaft turbid. 
 
 The ufe of pearl afhes, inftead of fait of 
 tartar, which is dire&ed by the Edinburg- 
 college, or indeed of any other fixt alkaline 
 fait, atprefent in ufe, is an obvious faving ; and 
 comes within the latitude given by the college 
 pf London. 
 
 This fpirit, however, is almoft wholly ex- 
 cluded pra&ice, by the ufe of that, made with 
 quick-lime, notwithftanding the college of 
 London have endeavoured, to prohibit the ufe 
 of volatile fpirit' made with lime, on account 
 of its fuppofed acrimony - y as was before men- 
 tioned. But the much greater pungency of 
 the kind with lime, which renders it much 
 fitter for the purpofe of fmelling to, on which 
 account a great part of the demand is made, 
 together with the inconvenience of keeping an- 
 other kind for other ufes, occafions it to be 
 almoft univerfally fold, inftead of that with 
 alkaline fait, by the wholefale preparers and 
 dealers in medicine, to the apothecaries and 
 retailers : and it is, therefore, proper to in- 
 quire into the beft method of preparing it : 
 efpecially as one particular medicine, the col- 
 lege themfelves have given a place to in their 
 laft pharmacopoeia, cannot be prepared with- 
 out it ; I mean volatile tincflure of the bark, 
 which, in the ipirit made with fixt alkaline fait, 
 becomes only a mucilage. 
 
 Volatile 
 
Chemical Preparations* ii$ 
 
 Volatile fpirit of fal Ammoniacum made with 
 quicklime. 
 
 Take of fal Ammoniacum, in fine pow- 
 der, one pound, of quicklime, which has 
 laid in the air till it be broken to powder, 
 two pounds , mix them well, and put them 
 prefently into a retort, with two pounds of 
 water : fhake them, to mix the powder and 
 water ; and place the retort in a fand-heat - y 
 diftill off about twelve ounces : but, ths 
 receiver being changed, about four ounces 
 of weaker may be alfo drawn off. 
 
 Note. 
 
 This is the former procefs, ufed for the pre* 
 parations of this fpirit $ but it is faulty in feveral 
 refpedts. 
 
 The expofing the lime to the air, is (o far 
 from neceffary, as to be very injurious to the 
 qualities, by which it operates in this procefs : 
 the quantity, alfo, of the lime, is much greater 
 than needful $ both filling the retorts with need* 
 lfcfs matter, fo as to render the produce of the 
 operation lefs, by even two thirds, than it may 
 be by a better proportion of the quantities $ to 
 the great increafe of the expence and trouble; 
 and caufing them, likewife, frequently to break 
 I z during 
 
u6 Chemical Preparations. 
 
 during the operation ; to the lofs of half, or 
 more, of the fpirit. 
 
 The powdering the fal Ammoniacum, or 
 making any previous mixture of it with the 
 lime, before they are put into the retort, is 
 likewife wholly needlefs ; for the fait will of 
 courfe melt in the fluid as the warmth in- 
 creafes. 
 
 The quantity of water is likewife much too 
 fmall : for at leaft twice the weight of the fait 
 may be drawn off; according to the proportion 
 of the college in the fpirit with fait of tartar ; 
 and, as it is impradlicable to draw off the whole 
 fluid, (becaufe the retort will crack, when the 
 lime attains a certain degree of drynefs,) that 
 quantity of fpirit cannot be obtained with this 
 fcanty proportion of water. 
 
 The following method, therefore, is much 
 better ; amending thefe feveral errors ; and ac- 
 commodating the materials to each other in 
 due proportion. 
 
 Improved method of making the volatile fpirit 
 of fal Ammoniacum with quicklime. 
 
 Take of fal Ammoniacum four pounds, 
 quicklime five pounds, water three gallons. 
 Quench the lime in part of the water, and 
 then put it into the pewter alembic for 
 making this fpirit, defcribed p. 40 : add 
 
 to 
 
Chemical Preparations. 117 
 to it the fal Ammoniacum, and water ; and 
 place the retort in the fand-bath : where 
 diftill off ten or twelve pounds, and then 
 change the receiver ; fuffering, afterwards, 
 the fpirit to diftill, while any pungency re- 
 mains : this weaker fpirit muft be added, to 
 the materials in fome future operation, in 
 the place of fo much water. 
 
 Note. 
 
 By this diminution of the quantity of lime, 
 a retort will, at one operation, diftill at leaft 
 three times as much fpirit, as in the former 
 procefs : and will frequently ferve a fecond time 
 for the fame purpofes ; which can never hap- 
 pen when more lime is ufed. 
 
 It is ufual to draw off four or five times the 
 weight of the fal Ammoniacum ; and the fpirit 
 will, even then, appear extremely ftrong : but, 
 whoever would have this fpirit correfpondent 
 to that of the college, made with fixt alkaline 
 fait, muft only draw it off in the proportion of 
 three times the weight. 
 
 The ufe of quicklime, in making the vola- 
 tile fpirit of fal Ammoniacum, may be de- 
 tected by the fame trial of it, by means of 
 fpirit of wine, as has been given for the fpirit 
 of hartfhorn : but as the common trial is fub- 
 jeft likewife to the fame elufion, as was before 
 mentioned, the further means, before given, 
 
 1 3 ° f 
 
n8 Chemical Preparations. 
 
 of afcertaining the nature of the chryftals, pro- 
 duced on the addition of the fpirit of wine, 
 tfught alfo to be ufed. 
 
 Spiritus falls Ammoniaci dutch ; or dulcified 
 fpirit offal Ammo?tiacutn. 
 
 Take of any fixt alkaline fait half a pound, 
 fal Ammoniacum four ounces, proof fpirit 
 three pints : diflill with a gentle heat, till a 
 pint and a half be come over. 
 
 Note. 
 
 The proportion of the fixt alkaline fait to 
 the fal Ammoniacum is here, as before in the 
 old procefs for the volatile fpirit, double what it 
 needs to be : the quantity of proof fpirit is 
 likewife improper \ for either, out of the three 
 pints employed, half the quantity of real fpirit 
 muft be left behind ; or the fpirit, which comes 
 over, will contain much too little water, to keep 
 diflblved the quantity of volatile fait produced : 
 for, in order to have three ounces diffolved in 
 a pint and half of fpirit of wine, the fpirit ought 
 not to be ftronger than proof fpirit. But, as in 
 fad:, this procefs, fo far as regards the addition of 
 the fpirit of wine, produces nothing more than 
 a bare mixture of the folution of the volatile 
 alkaline fait, and the fpirit, (except the rectifi- 
 cation of the latter) it may properly be reje£ed ; 
 z and 
 
Chemical Preparations. 119 
 
 and the following Ampler manner fubftituted, 
 in its place, for obtaining the fame compofition. 
 
 Extemporaneous dulcified fpirit offal Ammo- 
 niacum. 
 
 Take of fpirit of fal Ammoniacum, made 
 with fixt alkaline fait, one pound : add to it 
 re6lified fpirit of wine half a pound ; and 
 fhake them well together. 
 
 Note. 
 
 This will be, in all refpe&s, the fame with 
 the other; and maybe made, occafionally, with- 
 out the trouble of a diflind: procefs : but, if the 
 fpirit be wanted, free from the appearance of 
 fait, which will be found in this mixture, as 
 well as in the fpirit produced by the procefs of 
 the college of London above given, water mufl 
 be gradually added, till the fait be diffolved ; 
 taking care, not to put in more than may be 
 fufficient to that end. 
 
 Spiritus volatilis aromaticus^ or fal volatile 
 oleofum. 
 
 Take of the efTence of lemons, and eflen- 
 
 tial oil of nutmegs, each two drams, of the 
 
 effential oil of cloves, half a dram, dulcified 
 
 I 4 fpirit 
 
120 Chemical Preparations. 
 
 fpirit of fal Ammoniacum, two pints s diftill 
 thei$£ with a flow fire. 
 
 Note. 
 
 This is a very good and elegant compofi- 
 tion: but the ufe of volatile fpirit, with the 
 proper proportion of fpirit of wine, will equally 
 well anfwer the end ; and fpare the procefs for 
 the making the dulcified fpirit. 
 
 In this procefs, which is that of the college 
 of London, it is intended, that a part of the 
 diffolved fait fhould remain in the fpirit ; in 
 order to fhew, that the fpirit contains the pro- 
 per quantity of fait 5 and that, it is not prepared 
 with quicklime ; but this is really no certain 
 teft of either : for there may be a falfe appear- 
 ance of volatile fait, given by the means above 
 hinted at, as well in this cafe as in thofe of 
 the fpirit of hartfhorn, and volatile fpirit of fal 
 ► Ammoniacum ; which fhould, therefore, be ex- 
 plored, by the method above given, where there 
 is any ground for fufpicion of fuch a fraud •> as 
 I have more than once feen this fophiftication 
 actually pra&ifed. 
 
 The fpiritus volatilis aromaticus may, how- 
 . ever, be prepared by a cheaper method than 
 this procefs ; preferving both the fame fenfiblq 
 and medicinal qualities, 
 
Chemical Preparations. 121 
 
 A cheaper method of making thefpiritas vola~ 
 tilts aro?naticus> refembling that of the col- 
 lege of London, and equally good with refpeSl 
 to the intention. 
 
 Take of the volatile fait of fal Ammonia- 
 cum, made with chalk, two pounds, or the 
 volatile fpirit, made with fixt alkaline fait, 
 of the full ftrength, fix pounds 5 (if the fait, 
 and not the fpirit, be ufed, three pints of 
 Water muft be added 3) put the fpirit, or 
 diflblved fait, into a retort, together with 
 eight pounds of proof fpirit, half a pound 
 of pimento or Jamaica pepper, two ounces 
 of caffia lignea, and one ounce of efTence 
 of lemons : place the retort in the back 
 part of the fand- bath ^ and diftill off the 
 fpirit and fait till there be a cloudinefs in 
 the drops \ then change the receiver, and 
 draw off the remaining fluid while it ap- 
 pears to have any fmell or flavour : this 
 weaker fpirit muft be added to the materials 
 with the next quantity made. 
 
 Note, 
 
122 Chemical Preparations. 
 
 Note. 
 
 The aromatic fpirit, thus prepared, will be 
 equally good with that of the college ; ond may 
 be made with much lefs trouble, and cxpence; 
 if the foul part of the volatile fal Ammoniacutn 
 be employed for it. 
 
 But it is very frequent, to fubftitute in the 
 place of thefe kinds, what is prepared by means 
 of lime : and the greater pungency which the 
 lime gives to the volatile fait in this fort, often 
 impofes even on apothecaries, not greatly verfed 
 in the preparation of chemical medicines ; and 
 makes them believe it to be good. Where 
 there is no undiflblved fait in it, the diftinguifh- 
 ing this kind, from that properly prepared, re- 
 quires a new method of proof; for the mixing 
 fpirit of wine, which avails with regaid to the 
 other volatile fpirits, is here evidently of no 
 ufe. The following trial fhould, therefore, be 
 made in this cafe, where the fophiftication by 
 lime is fufpe<5ted, and the fpirit is found very 
 pungent to the nofe. 
 
 Method of diftinguijhing when the fpiritus w- 
 latilis aromaticus is made with lime, in the 
 cafes where there is no undijfohedfalt with it> 
 and the fpirit is yet found extremely pungent. 
 
 Take a fmall quantity of the volatile fal 
 Ammoniacum, powdered, and put it gra- 
 dually 
 
Chemical Preparations. 123 
 dually into a phial, containing the fpiritus 
 volatilis aromaticus, which is to be proved : 
 fhake them well together ; and if the fpirit, 
 notwithftanding its great pungency, fenfi- 
 bly diflblve the fait, it may be taken for 
 granted, that it was made with lime j but 
 if the fait remain intirely undiffolved, or be 
 diffblved but in a fmall degree, the contrary 
 may be, with certainty, concluded. 
 
 SECTION II. 
 
 Of the preparation of thofe ?nedicines^ 
 where vegetable fubftances make the, 
 whole ^ or principal part of the fub- 
 jeEl. 
 
 Salt of wormwood. 
 
 Take any quantity of wormwood, either 
 frefh gathered, or dried gently ; put it into 
 an iron pot $ and, with a gentle fire, reduce 
 it to white afhes ; which are afterwards to 
 be boiled in a fufficient quantity of fpring 
 water, fo as to make a lye : filter the lye, 
 
 an4 
 
124 CHEMrcAL Preparations. 
 and exhale it, over a gentle fire, till a brown 
 fait be left behind - y which, by repeated fo- 
 liations, filtrations, and evaporations, may 
 be rendered white and pure. 
 
 Note. 
 
 The incineration, or burning, may be better 
 performed, upon a clean hearth, in fome place 
 where the wind cannot blow away the afhes : 
 and the repeated means of purification are 
 needlefs, not only becaufe they would fail to 
 render the fait more pure than the firft filtra- 
 tion alone, (provided it be performed through 
 paper) ; but, becaufe, if they did produce a pu- 
 rity, and whitenefs, in the fait, they would 
 render it unmarketable ; as being wholly un- 
 diftinguifhable from fait of tartar. 
 
 This fait does not differ from the fixt alka- 
 line fait, obtained from any other vegetable, 
 by the fame means - y nor from fait of tarta^ ; 
 except that in the preparation of the laft, a 
 greater calcination being made, the burnt oil is 
 deflroyed, which gives to the fait of worm- 
 wood its brown colour. 
 
 It is very ufual, therefore, to fubftitute the 
 fait of other vegetables, for that of worm- 
 wood ; there being no medicinal difference be- 
 twixt them, as Ve have before obferved ; as 
 both the fixed falts and burnt oils of all vege- 
 tables are, when pure, alike in their qualities : 
 but a fictitious fait may be made from pure fixt 
 
 alkaline 
 
Chemical Preparations. 125 
 
 alkaline fait, exa&ly the fame with the fait 
 really obtained from wormwood, by the above 
 procefs, if the following means be ufed. 
 
 FiSlitiom fait of wormwood, not differing, in 
 any refpeB, from the genuine, but with re- 
 gard to its production. 
 
 Take a little wormwood, and reduce it to 
 the ftate of an imperfect charcoal, by burn- 
 ing it in a crucible, covered from the air ; 
 it mull not neverthelefs be burnt till the 
 flaming quality be deftroyed, but taken from 
 the fire as foon as it is perfe6lly black. Put 
 fome of this coal, together with a pound 
 of pearl afhes, into four pints of water, 
 and boil them together : let them ftand till 
 they are cool, and then filter through pa- 
 per, and evaporate to a dry fait ; to which 
 the burnt oil of the coal will have imparted 
 a proper degree of brownnefs -, that, if too 
 great, muft be adjufted by the addition of 
 more pearl afhes purified by the filter. 
 
 Note. 
 
 This contains unqueftionably the fame ele- 
 ments, as the true fait of wormwood : fince 
 the oil, in which alone, there can be pofiibly 
 
 fuppofed 
 
126 Chemical Preparations* 
 
 fuppofed any difference, is here the fame as in 
 that* 
 
 This fubftitution may, therefore, be well 
 allowed, in any view : and, with refped: to the 
 medicinal effedts, the fubftitution of fait of 
 tartar, or any other fixt alkaline fait, for the 
 fait of wormwood, cannot be condemned on 
 any maintainable principles, as any way in-> 
 jurious, or infufficient to the intention of cure ; 
 according to what we have before fhewn. 
 
 Salt of tartar. 
 
 Let crude tartar of either kind, folded 
 up in wet brown paper, or contained in a 
 proper vefTel, be put into the fire, and con- 
 tinued there, till all the oil be burnt out r 
 the fait is then to be procured from it, by 
 folution in boiling water ; with a fubfequent 
 evaporation, after having been filtered thro* 
 paper. 
 
 If the fait be required of a more fapona- 
 
 ceous and pungent nature, let it be fufed, 
 
 in a crucible, for fome hours, with a very 
 
 hot fire, till it acquire a greeniih, or &ue 
 
 colour. 
 
 Note. 
 
 Salt of tartar was alfo formerly made by de- 
 flagrating nitre and tartar: which may be done, 
 
 by 
 
Chemical Preparation^ 127 
 
 by powdering them together, in the proportion 
 of two parts of tartar to one of nitre 5 and then 
 putting the powder, gradually, by a fpoonful 
 at a time, into a crucible, heated red hot ; 
 which muft be kept in the fire during the 
 operation, and for fomc time after : The fait, 
 being thus duly calcined, muft be diffolved, 
 and purified, as in the other proceffes, by fil- 
 tering. But all thefe methods are greatly di£- 
 ufed at prefent ; the wholefale dealers having 
 learnt the fecret of preparing a fixt alkaline 
 fait, by the following much more profitable 
 method, which is now for the moft part ufed 
 in the place of fait of tartar. 
 
 FiSlltious fait of tartar. 
 
 Take of the beft pearl afhes, any quan- 
 tity ; diffolve them in boiling water, in the 
 proportion of a pound to a quart 5 when 
 they are diffolved, let the folution Hand till 
 it be cold ; and then filter it through paper: 
 being filtered, evaporate the fluid, till a dry 
 fait remain ; which, being broken into a 
 grofs powder, muft be put into a proper 
 bottle of glafs or ftone, and kept carefully 
 from the air. 
 
 The evaporation may be performed in a 
 clean iron pot -, but not in an earthen pip- 
 kin ; 
 
128 Chemical Preparations. 
 kin ; and the greateft care fhould be takefl 
 neither to let the folution, or fait, be put 
 into copper, or brafs veffels, on any account. 
 
 Note. 
 
 This, according to the principles before laid 
 down, is, in all refpe&s, the fame as fait of tar- 
 tar : and fixt alkaline fait being a medicine, 
 which both ufed (imply, and in the febrifuge 
 draughts, is of the higheft efficacy, and con- 
 fumed in very great quantity : the fubftitution 
 of this cheaper kind for the fait of tartar, which 
 cannot be prepared without much greater coft 
 and trouble, is rather a benefit to the public, 
 than a detrimental fraud. 
 
 The negled: of the caution, above given, of 
 avoiding the ufe of brafs or copper utenfils, in 
 the preparation of fait of tartar, or this fubfti- 
 tute, frequently occafions it to be very noxious : 
 for by powdering it in brafs mortars, from 
 which it immediately collects all the ruft, or 
 indeed makes itfelf a corrofion if there be the 
 leaft moifture, an emetic quality is acquired ; 
 which affefting thofe, who take the fait in any 
 form, induce them to believe the medicine it- 
 felf difagrees with them, from its own nature. 
 
 The pearl afhes are frequently adulterated 
 greatly with fea fait ; but this may be perceived 
 by the tafte if a fmall quantity be diflblved, 
 for that purpofe : and though, perhaps, they 
 cannot be eafily procured in a pure flate, yet 
 
 if 
 
Chemical Preparations. 129 
 
 if the folution be made in the proportion above 
 directed for the water and fait, the greateft 
 part of the fea fait will chryftallize, en the 
 fluids being fuffered to cool before it be fil- 
 tered ; and by this, a feparation of the greateft 
 part will be made; and the remaining fmall 
 part will not deprave the fixt alkaline fait, for 
 any medicinal purpofe. 
 
 Oil of tartar per deliqutum. 
 
 Take any quantity of fait of tartar, 
 highly calcined : put it, in any ftone, or 
 glafs, veflel, of a flat form, into a cellar, or 
 any moift place: where let it Hand, for 
 feveral days, till the fait be diflblved, by the 
 humidity of the air; then filter it through 
 paper ; or feparate the fluid from the dregs 
 by decantation. 
 
 Note. 
 
 As this is no way different from any other* 
 folution of the fait, of equal ftrength ; or, as, if 
 any change be produced by this method of fo- 
 lution, it can be only a depravity of the alka- 
 line quality by the acid of the air, this procefs is 
 needlefs : and, therefore, the following extem- 
 poraneous method of making this deliquium, 
 is ufed inflead of it* 
 
 K Extern- 
 
130 Chemical Preparations, 
 
 'Extemporaneous method of making oil of tartar 
 per deliquium. 
 
 . Take of fictitious fait of tartar, above- 
 mentioned, any quantity : diflblve it, by 
 boiling, in half its weight of water; and 
 filter the folution when cold. 
 
 If any fait precipitate to the bottom of the 
 veffel, in the cooling of the folution, or be 
 found in the filter, it may be faved ; and put 
 to the pearl afhes, when the fictitious fait of 
 tartar is to be made from them; or ufed for 
 any fuch other purpofe. 
 
 Note. 
 
 This is a much more expeditious and com- 
 modious method, than the tedious manner of 
 diflblving the fait, by the moifture of the air : 
 which does it fo imperfectly, that a great waftc 
 generally accrues. 
 
 Soluble tartar. 
 
 Take, of any fixt alkaline fait, one pound, 
 of water, one gallon: to the fait, diflblved in 
 the water boiling, throw in cream of tartar, 
 gradually, till the effervefcence, that before 
 
 arofe 
 
Chemical Preparations. 131 
 arofe on each addition, ceafe to appear ; 
 which will be, when, or before, three times 
 the weight of alkaline fait has been thrown 
 into it : then filter the folution through 
 paper ; and, after a proper evaporation, let 
 it be fet to fhoot into chryftals ; or otherwife 
 make a total exhalation of the water, that 
 the fait may remain in a folid mafs* 
 
 Note. 
 
 As there is no neceffity of a boiling heat, 
 for the combination of the cream, and fait, 
 of tartar, into the foluble tartar ; and, as this 
 medicine is never given in a dry form ; it has 
 been a practice with fome, to fpare all parts 
 of this procefs, but the powdering the ingre- 
 dients ; and to fubftitute the following Ample 
 preparation, in the place of the other. 
 
 Extemporaneous foluble tartar* 
 
 Take of any fixt alkaline fait, three pounds, 
 of cream of tartar, one pound : powder, and 
 mix them thoroughly together. 
 
 Note. 
 
 This will, on diflblving in any fluid, previous- 
 ly to its being taken, become exadtly the fame, 
 K 2 a 
 
132 Chemical Preparations. 
 as if it had patted through the other omitted 
 parts of the above procefs ; and cannot, there- 
 fore, be deemed a fubftitution of a very cri- 
 minal nature. 
 
 In the preparation of this, it is proper to ob- 
 ferve, ftri&ly, the fame caution, as in the cafe 
 of the fait of tartar, with regard to copper or 
 brafs veffels. 
 
 Sal polychrejium folubile y or, felle de Seignette. 
 
 Take of the allies of the kali of Alicant 
 any quantity, extract the fait according to 
 art : and calcine it in a crucible, with a 
 ftrong heat, that it may be freed from ful- 
 phur ; and afterwards form it into chryftals. 
 
 Take, of the chryftals of the fait of the 
 kali, twenty ounces • diffolve it in four pints 
 of water ; add to it four pounds of cream 
 of tartar, or fufficient to neutralize it : fil- 
 ter the folution, and fet it by ; that the 
 fait may fhoot into chryftals. 
 
 Note. 
 
 This is the procefs of the pharmacopeia of 
 the faculty of Paris, for the making the felle 
 de Seignette ; which has lately been introduced 
 into practice here ; prepared by the apothecary's 
 company j and prefcribed by fome eminent per- 
 
 fons j 
 
Chemical Preparations. 133 
 
 fons; under the newfangled names of felle de 
 Seignette, or fal Rupilienfe : though it is ob- 
 vious, on the perufal of the procefs, even to thofe 
 who are but the leaft acquainted with matters 
 of this kind, that it is no way different from 
 the tartarum folubile, long known here ; and 
 given in feveral fucceffive editions of the phar- 
 macopoeia of the college, and moft other mo- 
 dern books, which treat of the preparations of 
 medicines. 
 
 Nor does, indeed, the procefs itfelf, for the 
 felle de Seignette, differ in any circumftance, 
 even of form, from thofe given for the foluble 
 tartar; except, in diredtingaprevious preparation 
 of the fixt alkaline fait, to be made from the kali 
 of Alicant; which fait, when calcined, as there 
 directed, to free it from the burnt oil, will be 
 no way different, (according to the principles 
 we have before laid down,) from any other 
 fixt alkaline fait calcined to perfect purity : 
 and were, indeed, the fait of the kali of Ali- 
 cant, fuperior, in any qualities, to other fixt 
 alkaline falts, fo as to give fome foundation, for 
 diftinguifhing the foluble tartar, prepared from 
 it, by a peculiar name, could the prefcribers of it 
 here expeft, or the preparers pretend, that it 
 is fetched from Spain for this purpofe : but that 
 fait of tartar, or fome other fixt alkaline fait is 
 ufed inftead of it. They may, indeed, fay, that 
 we have a Spanifh fait here under the name 
 of Barillas, that is the fame with the fait 
 of the kali 5 and they may equally well fay 
 the fame of the Ruffian pearl aflies, or any 
 K 3 other 
 
134 Chemical Preparations. 
 
 other fixt alkaline fait prepared in the fame 
 way. 
 
 There is, indeed, a particularity pradlifed in 
 the preparation of the fait of kali, here directed, 
 (which is the forming it into chryftals) that 
 is never done in the cafe of other fixt alkaline 
 falts : but this can no way make any difference 
 in the compofition of this medicine, being only 
 an accidental form, or configuration, of mafles 
 of the fait, and no variation of its abfolute na- 
 ture : and, indeed, the reafon why the chry- 
 ftallization of fixt alkaline falts is wholly neg- 
 lefted, is owing to its being not in the leaft ne- 
 ceffary, or conducive to any one end, or purpofc, 
 to which thefe falts are applied in medicine. 
 
 Wherever, therefore, felle de Seignette is 
 prefcribed or demanded, the foluble tartar, pre- 
 pared according to the procefifes above given for 
 it, may be adminiftered or fold ; as it is in facft 
 the fame : only, to fupport the due appearance, 
 it is neceflary, that it fhould be fhot into chry- 
 ftals 5 and not evaporated, as ufually, into a 
 dry mafs : chryftals being the form which the 
 Parifian difpenfatory direcfts. 
 
 Of cremor tartan's, or cream of tartar. 
 
 Let the crude tartar be powdered, and 
 diffolved, in fixteen or eighteen times its 
 weight of water in the boiler, which is 
 defcribed p. 34 as part of the apparatus for 
 
 making 
 
Chemical Preparations. 135 
 making this fait : let the heat be then 
 checked, that the fluid may ceafe to boil ; 
 and after it has flood at reft, in a heat near 
 that of boiling j but lefs than will produce 
 any ebullition, till it become clear by the 
 fubfiding of the feces, turn the cock of the 
 pipes, which makes the communication be- 
 twixt this boiler and the cylinders ; (defcribed 
 as a part of the apparatus) ; and, when the 
 cylinder is filled with the folution, turn a- 
 gain the cock, and flop the communication ; 
 let the fluid then remain in the cylinders, 
 till the chryftals be formed at the bottom 
 and fides j and then return back the mo- 
 thers into the boiler ; and add a frefh pro- 
 portion of crude tartar ; repeating the fame 
 operation till a confiderable quantity of 
 chryftals are crafted on the cylinder : but, 
 if the fluid, on returning it into the boiler, 
 appear to abound in feces or foulnefs, 
 pafs it through a large flannel bag ; and 
 add, if neceflary, a frefh quantity of water, 
 as well as crude tartar, to fupply what is 
 confumed in the boiling : when a fufficient 
 quantity of chryftals are formed in the cy- 
 K 4 Under* 
 
136 Chemical Preparations. 
 Under, they mull be taken out into bafkets ; 
 and, the fluid being drained off, they muft 
 be dried for ufe : the cake of chryftals at 
 the bottom of the cylinder, which will 
 generally prove foul from the fediment, 
 muft, if found fo, be returned into the boiler 
 along with the crude tartar. 
 
 Note. 
 
 By this method, a great quantity of the fait 
 may be purified, and chryftallized ; which, by 
 common methods, is impracticable; as it re- 
 quires fo very large a proportion of water, for 
 the diflblving it ; and, confequently, becomes 
 much too voluminous to be managed in glafs 
 veflels, as other falts. 
 
 It has been faid, that the common prepara- 
 tion of cream of tartar, which is in the hands 
 of a very few perfons, is not a purification and 
 chryftallization only ; but an adulteration, by 
 means of white earth added to it in the fo- 
 lution. But I think the contrary of this is evi- 
 dent, from the qualities of the fait, as we gene- 
 rally find it : for, allowing that there were a 
 redundant portion of a unneutralized acid, in 
 the crude tartar, and that, fuch acid combining 
 with this white earth, another fpecies of fait 
 might be formed, together with the chryftals 
 of the tartar ; yet this earth would become ap- 
 parent on the admixture of fixt alkaline fait in 
 
 the 
 
Chemical Preparations. 137 
 
 the preparation of the tartar folubilis 5 or on 
 any other occafion : as it would be then necef- 
 farily precipitated 5 and render the fluid white 
 and turbid, while in an agitated ftate, fettling 
 afterwards in the form of a powder. Now, 
 this appearance not being found to happen, we 
 may certainly conclude, that there is no adul- 
 teration of this fait by means of any earth ; 
 iince the power of fixt alkaline fait, which pre- 
 cipitates the earth, from all neutral falts, of which 
 it is the balls, is a fure teft, in this, and all other 
 cafes, where it may come in queftion, whether 
 fuch falts be formed of earth, or not. 
 
 Vitriolated tartar. 
 
 Take, of green vitriol, eight ounces, of 
 water, four ounces ; throw fait of tartar, 
 or any other fixt alkaline fait, to the vitriol, 
 diffolved in the water boiling, till all ebulli- 
 tion ceafe j which will be, when four ounces, 
 or fomething more, of the fait has been 
 ufed : then filter through paper ; and, after 
 due evaporation, let the fluid ftand, that the 
 falts may fhoot. 
 
 Note. 
 
 Vitriolated tartar is, with much more con- 
 venience, made from oil of vitriol, than from 
 the crude vitriol : Iince, as the only reafon, for 
 
 the 
 
138 Chemical Preparations. 
 the preference of the vitriol to the oil, muft be 
 the laving made in the price, even that will 
 fcarcely hold good, when all things are consi- 
 dered : and, as the large quantity of oker, 
 precipitated from the vitriol, retains, unavoida- 
 bly, a confiderable quantity of the folution, in 
 the filter 5 and, consequently, occalions a pro- 
 portionable wafte of the vitriolated tartar. But, 
 if there really was a faving in the expence of the 
 materials, it would not countervail the trouble 
 and depravity of the fait, which are apt to at- 
 tend on this method of making it : for, if the 
 operation be not conducted with the greateft 
 care, and even fome good luck, a difagree- 
 able ochrous flavour, and brown colour, will 
 be found in the fait produced : from which, 
 indeed, it is fcarcely poflible to keep it free, 
 when prepared from crude vitriol. 
 
 It is, therefore, much better to ufe the oil 
 of vitriol inftead of the fait ; and, in that cafe, 
 the procefs may be the fame in all other refpefts. 
 
 It is almoft an univerfal practice, to fubftitute, 
 in the place of the vitriolate tartar, thus pre- 
 pared regularly, the caput mortuum taken out 
 of the retorts after the diftillation of fpirit of 
 nitre, prepared from oil of vitriol ; and as this 
 is done, without any other preparation than 
 powdering, the fait, generally contains a con- 
 fiderable quantity of oil of vitriol, which the 
 fire has not been powerful enough to raife in 
 the diftillation as commonly managed ; and 
 1$, therefore, though in other refpefts the fame 
 with the vitriolated tartar prepared in the 
 
 manner 
 
Chemical Preparations. 139 
 
 manner above dire&ed, very unfit to be ufed, 
 in the cafes, where this medicine is moffc fer- 
 viceable ; as a dofe, fufficient to aft in the ca- 
 thartic intention, will fometimes contain much 
 more oil of vitriol, than fhould, at any time, 
 be given ; whereas, moreover, on this occa- 
 fion, any quantity is improper. This fubftitu- 
 tion, however, with due preparation, may be 
 very well allowed ; for, on being duly neutra- 
 lized, and formed into chryftals, this fait dif- 
 fers, in no refpe&s, from that prepared by the 
 moft regular method, and it may be, there- 
 fore, thus managed. 
 
 Manner of preparing vitriolated tartar from 
 the caput mortuum^ remaining after the di- 
 jiillation of aquafortis by Glauber s method. 
 
 Take, of the caput mortuum, any quan- 
 tity -, difFolve it in water boiling ; and add 
 to it, pearl afhes, in the proportion of one 
 ounce to every pound -, or two ounces, if 
 the caput mortuum appear very acid to the 
 tafte : filter the folution ; and chrvftallize 
 the fait. 
 
 Note. 
 
 By this method, this moft valuable medi- 
 cine, for which hereafter there will probably 
 be a very confiderable demand, may be made 
 
 extremely 
 
140 Chemical Preparations. 
 extremely cheap, and perfe&ly good. At 
 prefent, the depraved ftate, in which it is fold, 
 prevents its being prefcribed under this name : 
 and, indeed, this abfurd fubftitution has fo far 
 prevailed ; that the acid tafte, and the form of 
 a powder, are looked upon as eflential quali- 
 ties, in the {hops. But, whoever would have 
 the vitriolated tartar, in a perfeft ftate, muft 
 afk for it under the name of fal polychreft ; 
 which, though directed, in difpenfatories, to 
 be prepared by different means, is yet the fame 
 fubftance, in every refpeft, as was before fhewn. 
 It is, likewife, always advifeable to infift on 
 having this fait in the form of chryftals, and 
 not powdered ; to prevent the impoiition 
 abovementioned ; or others which may be 
 attempted. 
 
 The chryftals of this fait refemble greatly 
 to the fprigs of chryftal ftone, but of a lefs 
 length, by which appearance, they may be 
 eafily known from the fal catharticum, or any 
 other. 
 
 Dijlilled vinegar. 
 
 Let vinegar be diftilled, with a gentle 
 heat, as long as it will rife without any 
 empyreumatic fmell. 
 
 Note. 
 
 This is the direction of the college, with 
 refpeft to this preparation $ and, I think, it 
 
 may 
 
Chemical Preparations. 141 
 
 may be efteemed unfortunately defective ; as 
 the not didating in what kind of veflels the 
 diftillation fhould be made, has given counte- 
 nance to a pra&ice, which both before, and 
 fince, has greatly prevailed, of performing this 
 operation in the worm ftill. Now the worm 
 being in general made of bad pewter ; in the 
 compofition of which, lead has the greatefi: 
 part, the vinegar, by paffing through fo long a 
 tube of this metal, of which it is a ftrong 
 menftruum, cannot fail to diflblve a confi- 
 derable quantity. The college of Edinburg 
 have feemed properly apprifed of this incon- 
 venience, for they order the alembics, for this 
 life, to have glafs heads. What the ill effedts 
 of fugarof lead, internally taken, may be, Ifhali 
 not particularize here, as they are the fame with 
 thofe, fo frequently feen in perfons, who work 
 with lead : but that this bad practice may be 
 detected, and the ufe of vinegar, thus depraved, 
 avoided by thofe who are duly cautious, I offer 
 the following infallible method of difcovering, 
 where the vinegar is impregnated with lead in 
 any material quantity. 
 
 Method of difcovering , where vinegar is de- 
 praved with lead, by diftillation with a 
 worm. 
 
 Take fome of the vinegar queftioned, 
 and add to it a fmall quantity of the folu- 
 
 tion 
 
142 Chemical Preparations. 
 tion of any pure fixt alkaline fait : if a clou- 
 dinefs, or milky turbidnefs, enfue, and a 
 white powder be afterwards precipitated, it 
 may be concluded, the vinegar contains dif- 
 folved lead ; but, if the fluids retain the 
 fame clearnefs and tranfparency, after their 
 commixture, which they had before, the 
 contrary may be, with certainty, inferred. 
 
 Note. 
 
 This will be a certain teft of the purity of 
 the vinegar, with regard to lead -> as the fixt 
 alkaline fait has the certain power of precipi- 
 tating even the leaft quantity ; which mufl 
 become vifible, unlefs immaterially fmall. 
 
 In order, however, to take away this tempta- 
 tion, to the ufe of the worm, which the flow- 
 nefs of this operation, when performed in glafs 
 veilels, gives, I (hall recommend the following 
 method. 
 
 Compendious method of dijlilling vinegar. 
 
 Let the operation be performed in the 
 alembic defcribed p. 43 -, which fhould be 
 placed in the warmeft part of the fand-bath * 
 and, in the latter part of the operation, the 
 fand ihould be raifed round the alembic, 
 
 that 
 
Chemical Preparations. 143 
 that the upper part of it may be as much 
 heated as poffible. 
 
 Note. 
 
 By this method, not only a much greater 
 quantity may be diftilled at one operation, from 
 the increafed magnitude of the alembic, than 
 the ufeof retorts admits of 5 but, by railing the 
 fand near to the height of the arm, the vapour 
 of the heavier part of the vinegar, which is 
 with difficulty brought over the helm, may be 
 prevented from being condenfed on the fides 
 of the alembic, and remaining in the body of 
 it after the operation. 
 
 Dijlillation of oil of turpefttine. 
 
 Let the oil be diftilled from the turpen- 
 tine, in a proper alembics water being added 
 to it : the caput mortuum, left behind, will 
 be white refin. 
 
 Note. 
 
 This is performed but by few perfons ; fbme 
 great undertakers fupplying the whole con- 
 sumption. 
 
 The beft alembic for this purpofe, is that 
 
 defcribed p. 41. The pot may be made as 
 
 large as the founders can conveniently caft it, 
 
 and confequently very capacious; and a mode- 
 
 2, rate 
 
144 Chemical Preparations. 
 
 rate worm will be found fufficient for the 
 condenfation. 
 
 Tar has been fubftituted, in the place of 
 turpentine, for the obtaining this fpirit ; which 
 is the fame in both; and, in this cafe, the colo- 
 phony, or caput mortuum, left after the diftilla- 
 tion of the fpirit, will be pitch inftead of refin : 
 but, to keep this pitch in a vendible ftate, it 
 is proper not to rob it of too much of the 
 fpirit, which would render it of too dry and 
 brittle a nature, for moft purpofes. This fub- 
 ftitution of tar, for turpentine, may be autho- 
 rized in a medicinal view; as the fpirit ob- 
 tained from each is in all refpefts the fame, 
 
 Re£iified fpirit of wine and alcohol. 
 
 Take any quantity of French brandy, 
 and diftill off one half with a very gentle 
 heat : this re6lificd fpirit being digefted for 
 two days, with one fourth of its quantity of 
 fait of tartar dried and powdered, and 
 diftilled with a very gentle heat, becomes 
 alcohol. 
 
 Note. 
 
 It is immaterial from what kind of cruder 
 ipirit the reftified fpirit is made, provided there 
 be no foul empyreumatic fcent in it. The 
 much higher price of French brandy than 
 malt fjpirits, renders the latter preferable, on 
 
 which 
 
Chemical Preparations. 145 
 
 which account, the college of London have 
 given no procefs, but leave this preparation to 
 the diftillers, who can manage it with lefs ex-- 
 pence than thofe, who have occafion to rectify 
 fmall quantities only. But for the fake of fuch 
 as may not have an opportunity of procuring 
 highly rectified fpirits, or alcohol, on account 
 of their diftance from thefe large works, or 
 who may want alcohol ftronger than it is pre- 
 pared there, I fhall obferve, that the digeftion 
 of the fpirit and fait of tartar, as ordered in the 
 above procefs, is wholly unneceflary, and the 
 quantity of the fait far too large : and follow, 
 therefore, a much better method. 
 
 More expedite method of preparing highly rec- 
 tified fpirit of alcohol. 
 
 Take malt fpirit, rectified by one diftilla- 
 tion, any quantity : add to it pearl afhes, 
 heated red hot, and powdered grofly, with 
 the greateft difpatch, to prevent their cool- 
 ing, in the proportion of one ounce of the 
 fait to a pound of the fpirit 5 fhake the veflel 
 for fome time, and after it has flood half an 
 hour, or longer, repeat the fhaking again 
 for feveral times : the fait will then be dif- 
 folved; and, having attrafted the water, will 
 occafion its feparation from the fpirit, which 
 
 L will 
 
146 Chemical Preparations. 
 will rife above it ; and muft be parted from 
 it by decantation. To the fpirit thus fepa- 
 rated, then add, to every pound, one ounce 
 of the fait, heated and powdered as before; 
 and proceed again in the fame manner as at 
 firft. After this fecond decantation of the 
 fpirit from the fait, diftill it in a retort, with 
 a very large receiver, in the moil: gentle part 
 of the fand-bath. 
 
 If the fpirit be not required very ftrong, 
 the addition of the fecond quantity of the 
 pearl afhes may be fpared \ and where it is 
 wanted exceedingly ftrong, a third may be 
 employed. 
 
 Note, 
 i 
 
 The feparation of the phlegm from the fpirit, 
 being made by the fixt alkaline fait, before the 
 diftillation, that operation is only required, in 
 order to free the fpirit from a very fmall quan- 
 tity of it, which may remain diffolved in the 
 unfeparated phlegm of the fpirit : but, as the 
 prefence of the fait does not in the leaft deprave 
 the fpirit for any medicinal purpofes, the trou- 
 ble of the diftillation may be fpared; and the 
 alcohol applied in this ftate to all fuch ufes. 
 But, with refped>to fome other ufes, in which 
 it is employed in fome trades and manufactures, 
 
 particularly 
 
Chemical Preparations. 147 
 
 particularly in the making laquers and var- 
 nifhes, the diftillation is indifpenfibly necef* 
 fary ; as the alkaline quality of the fait would 
 change the colour of the gum ufed in compo- 
 sitions of that kind 3 and other inconveniences 
 might arife from the prefence even of the finally 
 eft quantity of the fait. 
 
 Boerhaave invented and recommended a 
 Species of alembic for this purpofe, in which, 
 means of a very tall head, of a conical form, he 
 pretended the fpirit might be freed, more effica- 
 cioufly, from the phlegm, in one rectification, 
 than by feveral, in the other kinds of alem- 
 bic employed for this end : hecaufe, as he fup- 
 pofed, the vapour of the phlegm and fpirit 
 afcending up this tall head, would come in 
 contact with the fides of it, which being 
 heated by them beyond the degree that fpirit 
 of wine can endure, without rifing in va- 
 pour, and yet under that which is fufficient 
 to raife water, the fpirit would, therefore, be 
 continued in the ftate of vapour, and pafs into 
 the pipe which is defigned to carry it from the 
 head to the refrigeratory; and the water be con- 
 denfed in the head itfclf ; and run back into 
 the body of the alembic. But though this 
 appears very fpecious in theory, it is of little 
 avail in practice ; for one point of heat alone 
 being requifite in the head to effect this pro- 
 perly, it is impradicable to maintain it 3 and if 
 there be lefs, the fumes of the fpirit will not 
 be raifed to the top of the head, fo as to pafs 
 into the pipe ; or if more^ the water will pafs 
 
 L 2 with 
 
148 Chemical Preparations. 
 
 with it; as always happens fhortly after the 
 proper degree of heat be obtained. 
 
 Ethereal fpirit. 
 
 Take, of fpirit of wine, four pints, of oil of 
 vitriol one pound : mix, and diftill them ac- 
 cording to the dire6lions below given for the 
 fpiritus vitrioli dulcis. Take the fpirit which 
 comes over ; and add, to it, of oil of tartar 
 per deliquium, or of the faturate folution 
 of any fixt alkaline fait, four ounces, and 
 mix them well together ; and a fubftance, 
 of the appearance of oil, will then rife on 
 the furface of the fluid ; which muft be 
 taken off as quickly as pofhble ; for it will 
 exhale almoft inftantly, if it be expofed to 
 the air : add then further quantities of the 
 folution of the fixt alkaline fait, one ounce 
 at each time, and take off all the, oil that 
 fhall appear at each addition. It muft be kept 
 in phials, with glafs Hoppers, extremely well 
 fitted to them -, or it will efcape by its ex- 
 tremely great volatility. 
 
 Note. 
 
 This is the ethereal fpirit, which Frobenius, 
 a German chemift, firft introduqed the know- 
 ledge 
 
Chemical Preparations. 149 
 
 ledge of here. It was then accounted only a 
 curiofity ; but fince, it has a place given to it as 
 a medicine, in the laft edition of the difpenfa- 
 tory of the Edinburg-college. 
 
 Flowers of Benjamin. 
 
 Put powdered Benjamin into an earthen 
 pot, placed in fand : with a gentle heat, the 
 flowers will rife ; and may be caught in a 
 taper cone, fitted to the pot. 
 
 The Benjamin may be, otherwife, put 
 into a retort; and the flowers will rife, and 
 be collected in the neck. 
 
 If the flowers be tinged with yellow, they 
 are to be mixed with tobacco-pipe-clay, and 
 refublimed. 
 
 Note. 
 
 The college of London have given, in this 
 procefs, an intimation of the method of fu- 
 bliming the flowers of Benjamin, by means of 
 a paper cone ; which is far preferable to the 
 ufe of a retort, or to any other method praftifed : 
 but the directions are fo general and indiftinft, 
 that moft, who have tried to avail themfelves 
 of them, and have not been otherwife ap- 
 prized of the proper method, have greatly 
 mifcarried in their attempts ; I will, therefore, 
 fubjoin fome more particular dire<ftions, for the 
 management of this procefs with the paper cone. 
 L3 The 
 
15© Chemical Preparations*. 
 
 The pot is beft made of the ftone ware, 
 fuch as is manufactured at Vauxhall ; and it 
 (liould taper in fuch manner, at the top, that 
 the paper cone may exactly fit it. 
 
 The paper ihould be that called bloom, or 
 blotting paper ; the more fpungy,<*in its tex- 
 ture, the better : the cone ihould be formed of 
 two fheets laid together, and fo adapted to the 
 pot, as to come, only about two inches over the 
 fides of it, when put on. By having the cone 
 of paper thus double, the oil will be the more 
 abforbed, and the flowers by that means freed 
 from it. 
 
 It is beft not to put the pot, which contains 
 the Benjamin, immediately into the fand~pot; 
 but into another earthen pot, large enough to 
 contain it with fand round it ; which larger 
 earthen pot, being put into the fand-pot, may 
 be funk, orraifed higher, at pleafure: by which 
 means, the heat of the pot, containing the Ben- 
 jamin, may be varied in a very quick manner ; 
 and more eafily adjufled to the occafion 5 than 
 if it were placed in the fand-pot. The heat 
 muft be very gently raifed ; and continued at 
 that degree, which will raife the flowers in the 
 floweft manner ; and it may be known by the 
 warmth of the upper part of the cone, if it be 
 fufficient to that effe£t. 
 
 If the paper of the cone feem greatly foul 
 with the oil, it fhould be taken off, and a new 
 one fuppl>ied. 
 
 * By thefe means, with a very little experience, 
 as to that nicety in the degree, which admits 
 
 of 
 
Chemical Preparations. 151 
 
 of no defcription, the greateft part of the flowers, 
 in any quantity of Benjamin, may be obtained 
 white, without any fecond fublimation. 
 
 Purification, or refinement, of camphor. 
 
 Take, any quantity of crude camphor, 
 and put it into the glaffes defcribed as pro- 
 per for this ufe p. 30 : place the glaffes 
 upon the fand, in the pots made as dire£led 
 p. 25, for the fublimation of calomel ; 
 and give the furnace a gentle degree of 
 heat : the camphor will be raifed in fumes -, 
 which will coalefce, and form a cake on 
 the upper part of the glafs -, and the opera- 
 tion muft be continued, till the whole be 
 fublimed from the lower part of the glafs ; 
 which may be known by the abatement of 
 the heat in the upper : the glafs muft be 
 broken, when cool 5 and if there be any 
 foul part, in the cake of camphor, it muft 
 be feparated, in order to be refublimed with 
 any frefh quantity : the other part will be 
 then proper for ufe. 
 
 Note. 
 
 As the camphor muft be purchafed of the 
 Eaft-India company, in confiderable quantities, 
 
 L 4 to 
 
152 Chemical Preparations. 
 
 to make the being concerned in the refinement 
 of it profitable, there are very few who under- 
 take to meddle with it : but it is an article very 
 well worth the notice of thofe, who have the 
 knowledge, and opportunity, of managing it 
 rightly. 
 
 The greateft nicety is in properly adjufting 
 the heat ; which, if too great, endangers the 
 burfting out of the fumes, as they are very 
 elaftic from the great volatility of the cam- 
 phor 5 and making thence an intolerable wafte t 
 or, otherwife, if the fire be too low, the fumes 
 will fettle on the fides of the glafles, in the 
 form of flowers, without attaining the chry- 
 ftalline texture ; and, when thele flowers are 
 increafed to a certain quantity, will fall 
 down again into the bottom of the glafs, 
 and occafion a tedious, and almoft perpetual 
 circulation. The method, however, to judge 
 of the right heat, is to learn to diftinguifh it 
 by feeling the glafles ; and it is beft to keep it 
 up, at the higheft point, which can be main- 
 tained, without forcing the vapour out through 
 the neck of the glafs : and in order to effedt 
 this more eafily, it is proper to heat the fur- 
 nace to the due degree, and continue it fo for 
 fome time, before the camphor be placed upon 
 the fand. 
 
 There is another manner, in which cam-t 
 phor may be refined, with very little trouble, 
 by thofe who have occafion to rectify fpirit of 
 wine from proof fpirit ; it is as follows. 
 
 Purification^ 
 
Chemical Preparations- 153 
 
 Purification, or refinement, of camphor, by 
 folution in ff/irii of wine. 
 
 Take, any quantity of crude camphor j 
 and diflblve it in fpirit of wine ; making 
 the folution as ftrong as poffible : let it 
 ftand at reft, till all the feculencies be fub- 
 fided ; and then pour off the clear folu- 
 tion from ^the fediment : filtering the re- 
 maining foul part through paper : add very 
 clean water, then, to the folution, by very 
 fmall quantities, as long as any white tur- 
 bidnefs appears to be produced on its fur- 
 ther admixture : the camphor will then be 
 precipitated, to the bottom of the veffel ; 
 but will be found to be in form of a pow- 
 der 1 to reduce which into a chryftalline 
 cake, proper for fale, the fpirit of wine 
 being decanted off from it, and fome clean 
 water added, put it into a Florence wine 
 flafk, and place it in a gentle fand heat, till 
 the camphor be melted; when the flafk being 
 taken off immediately, and broken when 
 cold $ the camphor will be found to be 
 
 formed 
 
j 54 Chemical Preparations. 
 formed into a tranfparent cake, fuch as is 
 commonly fold, 
 
 N. B. The fpirk of wine, being re&ified, 
 will ferve again for the fame purpofe. 
 
 Note. 
 
 This is a very eafy and profitable method to 
 thofe, who have opportunities of rectifying the 
 fpirit of wine, thus lowered by the addition of 
 the water, along with other quantities ; as 
 giving, in that cafe, no additional trouble: and 
 even, where the fpirit of wine is purpofely to 
 be rectified, this is, perhaps, the eafieft way, 
 if the quantity of camphor to be refined be 
 considerable : though the firft procefs alone is 
 at prefent pradtifed. 
 
 SECTION III. 
 
 Of the preparation of medicines , where 
 f ojfile fub fiances y not metalline^ make 
 the whole^ or principal part of the 
 fubjeSl. 
 
 Calcined vitriol. 
 
 LE T green vitriol be put into one of 
 thofe earthen veffels, called pipkins, 
 which mull be only three parts filled with 
 
 its 
 
Chemical Preparations. 155 
 it -, place the pipkin over a common fire, in 
 a heat juft fufficient to make it boil : when 
 the ebullition is almoft over, the fp^ce the 
 vitriol at firft took up in the veffel will be ■ 
 greatly contracted 5 which muft be again 
 filled up with a frefh fupply of vitriol ; 
 and the boiling continued till this, alfo, be- 
 come quiet ; and the veffel muft be thus re- 
 cruited, till it become full of vitriol, after 
 all ebullition ceafe : the vitriol will be now 
 a hard white mafs ; and muft be freed from 
 the veffel -by breaking it. 
 
 If vitriol, calcined to rednefs, or as it is 
 called, colcothar, be wanted, the veffel fhould 
 not be broken, but put, with the vitriol in 
 it, either into the body of the fame fire, 
 where it was calcined to whitenefs, or into 
 a wind furnace 3 and there continued till 
 the vitriol appear red. After which it fhould 
 be feparated from the veffel which will ad- 
 here to it -, and, as foon as poffible, put into a 
 bottle, with a glafs ftopper, to prevent its 
 deliquating in the air ; to which it is in 
 this ftate extremely difpofed. 
 
 .Note. 
 
156 Chemical Preparations. 
 
 Note. 
 
 It h^sbeen ufual, in the procefles given for 
 this preparation, to neglecft any directions with 
 refpeft to the filling the veffel too full at firft, 
 by which means, the lofs of great part of it 
 has generally happened ; and the omitting, 
 alfo, to refill the veffel as the fpace of the firft 
 quantity contracts, occafions a lofs in the num- 
 ber of veflels ufed to calcine any quantity ; as 
 they mull always be broken : which, if this me- 
 thod be not pradtifed, will be, as three to one, 
 more than is neceflary. It is ufual to fubftitute 
 the caput mortuum, after the diftillation of oil 
 of vitriol, in long necks \ as, alfo, that left 
 after the diftillation of aqua fortis, where vi-* 
 triol is ufed, inftead of the vitriol calcined to 
 rednefs -, but where the calcined vitriol is 
 wanted to be applied as a ftyptic to flop 
 bleedings at the nofe, or elfewhere, this fub- 
 ftitution is improper ; as the too great calci- 
 nation of the vitriol, in the diflillation in long- 
 necks deftroys the ftyptic quality ; and in the 
 caput mortuum of the aqua fortis, but a part 
 of it is calcined vitriol ; and the other part a 
 fubftance, not correfpondent in the leaft to the 
 intention, and which, therefore, depraves the 
 calcined vitriol. 
 
 Oil of vitriol. 
 
 Take any quantity of vitriol calcined to 
 whitenefs : powder, and put it into the 
 
 earthen 
 
Chemical Preparations. i$j 
 earthen pots made for this purpofe (called 
 long-necks) : let them be placed in their 
 proper furnace, with a receiver luted 
 to each ; and raife the fire gradually to 
 the higheft degree, in which it muft be 
 continued, ib long as any white fumes ap- 
 pear to come into the receiver : the fluid 
 obtained in the receiver muft be afterwards 
 put into a retort •, and placed in a fand- 
 furnace : the fpirit, which firft arifes, muft 
 be taken out of the receiver as foon as the 
 drops, which fall from the retort, appear ex- 
 tremely acid : the remaining part muft be 
 brought over, by means of a ftrong fire $ 
 and the two kinds kept feparate for ufe ; 
 the one being called fpirit, and the other 
 oil of vitriol. 
 
 Note. 
 
 This is the authorized procefs ; but the pre- 
 paration of oil of vitriol being feldom made, 
 except by thofe, who carry on very large con- 
 cerns, and have no particular view to medi- 
 cine, the preferving two diftindt kinds is fel- 
 dom regarded : and, where fpirit of vitriol is 
 demanded, the oil lowered by an equivalent 
 of water, is fubftituted for it : and is, in 
 faft, the fame thing $ the acid, which rifes firft, 
 
 and 
 
158 Chemical Preparations. 
 
 and that which comes afterwards, differing In 
 nothing, but the being accompanied with a 
 greater or lefs quantity of phlegm, impreg- 
 nated with the fulphureous gas produced in the 
 burning. 
 
 This method, of producing the oil of vi- 
 triol, has been greatly excluded from ufe, by 
 the improvement made lately in the art of ob- 
 taining this fubftance from fulphur : by which 
 means, the price has been reduced, in the 
 wholefafe dealings, from ten pence, or one 
 fhilling per pound, to four pence. The procefs 
 was kept fecret for fome time ; and is as yet in 
 few hands : but, for the benefit of thofe, who 
 may either chufe to enter into fuch a work, in 
 order to fupply the market, or who may have 
 occafion for a confiderable quantity for their 
 own ufe, in any manufacture or bufmefs, I 
 fliall give here the moft expedite manner hi- 
 therto invented of performing this procefs. 
 
 Manner of extraSling the oil of vitriol from, 
 fulphur ', by means of the apparatus defcribed 
 p. 44. 
 
 Take, of crude fulphur or brimftone, five 
 parts, of crude nitre (or as it is called rough 
 nitre), 'one part, powder and mix them well 
 together : put this mixture, into the fpoon- 
 ftoppers, in three layers \ feparating each 
 
 layer 
 
Chemical Preparations. 159 
 layer by a thin wad of tow : fet fire, then, 
 to the fulphur and nitre, with which the 
 ftoppers are thus charged, and put them into 
 the necks of the globes -, which, having firft 
 a gallon of water poured into them, muft 
 be placed in their proper frames, on the 
 fand-bath 5 but muft not be fufFered to go 
 deeper into the fand, than the height of the 
 water : it muft be alfo understood, that the 
 fand fhould be previoufly fo heated, as to 
 raife a copious fteam in the globe ; but not 
 greater than can be condenfed, without 
 heating the fides confiderably. The flop* 
 pers being thus put into the globes, the 
 materials contained in them will conti- 
 nue to burn - y and will fill them with 
 white fumes ; which, meeting with the 
 fteam of the water, they will mix and be 
 condenfed together on the furface of the 
 glafs: as foon as the materials ceafe to 
 burn, which may be known by the cefTation 
 of the white fumes, let the ftopper be taken 
 out; and another charged, in the fame 
 manner with the materials, put in its ftead : 
 and let this be repeated, till each of the 
 2 globes 
 
160 Chemical Preparations. 
 globes contains three or four gallons of 
 fluid 2 then let them cool ; and, when cold, 
 take out the fluid by declining the neck by 
 means of the frame. 
 
 Let the weak oil, thus obtained, be then 
 put into retorts, and dephlegmated, by 
 drawing off the aqueous fluid, till the re- 
 maining part be of due ftrength ; the degree 
 of which maybe regulated by the proportion 
 that the water, put into the globes, bears 
 to the quantity of the weak oil when taken 
 out ; by obferving which, and fixing on a 
 proper ftandard for the ftrength, it may be 
 known when the oil is dephlegmated to the 
 due degree, by the quantity of water brought 
 over into the receiver, which fhould be mea- 
 fured, when it is imagined that near the pro- 
 per proportion is drawn off : but, as this 
 cannot be performed, with refpe£l to the 
 contents of one retort, without the repeated 
 trouble of taking off the receiver, it is 
 proper to dephlegmate the contents of fome 
 particular retorts higher, and by mixing 
 the feveral quantities dephlegmated in a 
 number together, and meafuring the re- 
 
 fpe&ive 
 
Chemical Preparations. i6i 
 fpe£tive quantities of phlegm in the re- 
 ceivers, alfo, the whole may be eafily 
 brought to the ftandard required, by means 
 of the produce of thofe retorts, whjch have 
 been higher dephlegmated; in order to fup^. 
 ply the deficience of fuch as may be too 
 low. 
 
 ■Note. 
 
 This is a method, by which oil of vitriol 
 may be obtained at a very low expence : efpe- 
 cially, if the quantity manufactured together 
 be very confiderable : and other preparations, 
 fuch as aqua fortis, fal mirabile, fublimate, 
 &c. in which the undephlegmated fpirit may be 
 ufed, are likewife carried on, together with 
 this. 
 
 The principle, on which the improvement 
 in this method depends, is, the burning the 
 fulphur with nitre, inftead of being obliged to 
 fuffer an accefs of air : the draught of which, 
 of courfe, carries off with it, the fumes of the 
 fulphur $ as was always found in the feveral 
 manners of the procefs, for diftilling thisfub- 
 fiance by means of glafs bells^or other fuch vef- 
 fels ; by thebeft contrived of which, but a fmall 
 quantity of the acid fpirit could ever be col- 
 lected. Whereas, by the ufe of nitre, the ful- 
 phur being burnt, in a clofe vefTel, without any 
 fteam of air to carry off the acid vapour - y 
 which, on the contrary, in this method, meets 
 M con- 
 
 
162 Chemical Preparations. 
 
 continually with the fteam of water, that 
 greatly affifts its condenfation, almoft the 
 whole quantity of this fubftance, contained in 
 the fulphur, is obtained : and by fuch expedite 
 means, as renders the expence fmall, where a 
 large work is carried on. 
 
 The invention of this method is generally 
 given to the perfons, who a few years ago took 
 out a patent for it : but it is very well known, 
 that Cornelius Drebbel, a Hollander, amongft 
 other improvements of arts, found out a me- 
 thod of obtaining five ounces of the acid fpirit, 
 from eight ounces of fulphur : and though the 
 practice of this art was, on his death, disconti- 
 nued, yet I can produce the model of an appara- 
 tus, for extra&ing the acid fpirit from fulphur by 
 means of nitre, which was made a confidera- 
 ble time before that patent was applied for. 
 
 Though I call this oil of vitriol, as almoft 
 the whole now fold, under that name, is the 
 fpirit of fulphur thus prepared ; and the acid of 
 vitriol does not differ from it, tvhen both are 
 pure, as was before (hewn p. 80 : yet this is 
 not, in reality, the pure vitriolic acid 5 for, by this 
 ufe of nitre, in its preparation, it contains an 
 eight or ninth part of fpirit of nitre ; which is 
 fet loofe from the nitre, in the deflagration. 
 But though this may poflibly deprave it, with 
 refpeft to fome nice experiments, and extraor- 
 dinary purpofes 3 yet it very well anfwers the 
 purpofe of pure oil of vitriol, with refpeft to its 
 ufe in the arts and manufactures, in which it is 
 employed ; and may be, likewife, allowed as 
 i a 
 
Chemical Preparations. 163 
 
 'A fubftitute, either for the oil of vitriol, or fpirit 
 bf fulphur by the bill, for all medicinal pur- 
 pofes. And this may, therefore, be looked 
 Upon, as one of the moft important inventions, 
 that have been of late made public, 
 
 Spiritus vitrioli dulcis, or dulcified fpirit of 
 vitriol. 
 
 Take, of oil of vitriol, one pound, recti- 
 fied fpirit of wine, one pint : mix them, gra- 
 dually* with the utmoft care : and diftill 
 them, with a very flow fire, till a black froth 
 begins to rife : then, immediately, let the 
 receiver be taken awav, left the froth rife 
 into the neck of the retort, and flow into it. 
 
 Note. 
 
 This is the procefs of the London college % 
 ift which, the proportion of oil of vitriol is 
 much gteater than has been generally ufed : 
 and indeed than is neceflary, as the far greateft 
 part of it will be left behind in the retort. The 
 college of Edinburg have ordered only fix 
 ounces of the oil of vitriol to four pounds of 
 the fpirit of wine : but as the oil of vitriol is a 
 very cheap ingredient, one pound to four may 
 be ufed ; which, if fomething more than fuffi-^ 
 cient, cannot, therefore, occafion any material 
 lofs. 
 
 M2 The 
 
164 Chemical Preparations, 
 
 The intention of fo large a quantity of oil of 
 vitriol, was, to render this a previous prepara- 
 tion for the elixir vitrioli dulcis : but, as there 
 can be only a certain proportion of the acid 
 raifed, by the fpirit of wine, the adding more, 
 in the undiftilled mixture, cannot produce a 
 greater proportion in the diftilled fpirit ; unlefs 
 a much ftronger heat than that of the fand- 
 baths, in which this medicine is, (and ought to 
 be,) prepared, were to be ufed. 
 
 In this procefs, the greateft care fhould be 
 taken, in mixing the two ingredients : for 
 which, the fafeft method is, to add the oil of 
 vitriol to the fpirit of wine, by fmall quanti- 
 ties ; and to let the mixture ftand each time, 
 without further addition, till it can be fhaken 
 without producing any fenfible heat. When 
 the' whole is commixt, it fhould, likewife, be 
 fuffered to ftand, fome time, before it be di- 
 ftilled : but there is no occafion for digefting 
 it feveral days; as is directed by the Edinburg 
 college. 
 
 The ufual adulteration of this medicine, is, 
 by lowering it with water; which may be per- 
 ceived by its lofing the volatile pungency, and 
 fuffocating fcent, that it gives to the air around 
 it, when any veflel containing it is opened. 
 
 Spirit of nitre. 
 
 Take, of fait petre, and oil of vitriol, 
 equal quantities, of water, the proportion 
 
 of 
 
Chemical Preparations. 165 
 of one fourth or fifth to the other ingre- 
 dients : mix the oil of vitriol, and water, 
 by adding the former to the latter in fmall 
 quantities - y giving time for the mixture to 
 cool betwixt each addition 3 to avoid the 
 heat, which will be otherwife excited, to fuch 
 a degree, as may break the veiTel that 
 contains the mixture, and produce other 
 inconveniences. Put the fait petre into a 
 retort, and afterwards the oil of vitriol and 
 water : when the whole is mixt together, 
 let them ftand fome hours, the mouth of 
 the retort being ftopt with paper 3 and then 
 lute on a receiver, and diftill them, with a 
 heat gradually raifed to the greateft degree, 
 while any red fumes appear to rife. 
 
 Note. 
 
 This is the regular and common procefs for 
 fpirit of nitre ; but it is faulty in feveral refpedts. 
 
 The quantity of oil of vitriol is far too great, 
 for that of the fait petre : half the weight of 
 oil of vitriol being fufficient, to difcharge its 
 proper fpirit from the nitre, as appears, as well 
 from clear reafons drawn from the nature of the 
 two bodies, as from experience : and, when 
 this redundant quantity of the oil of vitriol is 
 ufed, either near one half will be left behind in 
 . M 3 the 
 
i66 Chemical Preparations. 
 
 the retort, if the fire be not very powerful, or 
 the fpirit, which comes over, will not be fpirit of 
 nitre ; but a compound of almoft equal parts of 
 the fpirits of nitre and vitriol. It is impractica- 
 ble, indeed, to obtain a pure fpirit of nitre, 
 if this proportion be adhered to, which, tho* 
 not very important with regard to all medicinal 
 purpofes, is yet fb for fome ; as particularly in 
 the folution of mercury, for the preparation of 
 red precipitate ; and, in the greateft degree, 
 with refped: to the arts of gilding, and others, 
 where fpirit of nitre is wanted. On the con- 
 trary, the proportion of the oil of vitriol to the 
 nitre, in the dilpenfatory of the college of 
 London, is much too little : being but as one 
 to three; which is not fufficient to difcharge 
 the acid from the whole quantitity of nitre ; 
 and, therefore, not only waftes fo much of 
 the nitre, as a half exceeds a third, but, alfo, 
 diminiflies the produce of the operation, in 
 the fame proportion, by filling the retort in 
 part, with fruitlefs ingredients. 
 
 The putting the water, with the oil of vi- 
 triol, into the retort, is likewife an error, as it 
 protracts the operation ; and is of no ufe with 
 relation to the diflblving the falt-petre, as is 
 intimated in fome proceffes given for this pre- 
 paration ; but only in rendering the fumes more 
 condenfible y which end, it full as welt an- 
 fwers, when put into the receiver before it be 
 joined to the retort. 
 
 The ufe of purified nitre, or falt-petre, is, 
 alfo, an unnecefifary expence : for the crude 
 
 flitre 
 
Chemical Preparations. 167 
 
 nitre (or rough petre, as it is called) will 
 equally well anfwer the end : and is to be 
 procured at a confiderable lefs price. But 
 there being two kinds of this brought from the 
 Eaft-Indies, the one a purer kind, called the 
 white petre -, and the other a fouler, called the 
 brown, it is proper to take care, that the firft 
 of thefe kinds be employed ; efpecially, if the 
 fpirit of nitre be ufedfor any fuch medicinal, or 
 other purpofes, as require it to be pure : for 
 the brown nitre being feldom free from a con- 
 fiderable proportion of fea fait, the acid fpirit, 
 produced from it, muft be neceffarily an im- 
 perfedl aqua regia ; and, therefore, not fo fit 
 for gilding, and many other ufes. 
 
 I fhall, therefore, after treating of thofe 
 proceffes for the fpirit of niti 4 e, which are given 
 under the name of preparations of aqua fortis, 
 endeavour to {hew the moft expedient and 
 profitable method of obtaining pure fpirit of 
 nitre, proper either for thofe purpofes, whers 
 it is required to be pure ; or where the com- 
 mixture of oil of vitriol with it is necefiary. 
 
 Single aqua fortis. 
 
 Take, of crude vitriol, three pounds, of 
 nitre, two pounds : grind, and mix them 
 well together : put the mixture into earthen 
 veffels, called long -necks, which muft be 
 filled about two thirds ; and place them in 
 
 M4 a 
 
i68 Chemical Preparations. 
 a reverberatory furnace, made for this pur- 
 pofe : lute on receivers fitted to their necks ; 
 after which diftill, with a fire gradually 
 railed to the higheft degree, 
 
 Note: 
 
 By the words, aqua fortis, as diftinft from 
 fpirit of nitre, is to be underftood a compound 
 of fpirit of nitre, and oil of vitriol : for, from 
 the proportion of the vitriol ufed, as well in 
 this, as all the other proceffes given for acid 
 fpirits, under the name of aqua fortis, it will 
 be evident, on examination, that a quantity of 
 oil of vitriol muft rife along with the fpirit of 
 nitre 5 if the fire be of due ftrength : as the quan- 
 tity of vitriol ufcd, contains much more acid, 
 than can be fixed by the alkaline part of the nitre. 
 
 This is the procefs formerly ufed, for diftill- 
 ing what is improperly called the lingle aqua 
 fortis ; but ought rather to be called the weak : 
 as differing in nothing from that called the dou- 
 ble ; but in containing more water, on account 
 of the vitriols being ufed without any previ- 
 ous calcination. This, therefore, renders fuch 
 a procefs, in its nature, abfurd ; as being un- 
 profitable and needlefs : for, befide the incon- 
 venience, which is liable to happen, from the 
 ebullition of the vitriol, that occafions half 
 the contents to overflow, if the fire be not con- 
 duced with a caution more than is practicable, 
 till the water, which affifts in forming the chry- 
 ftals of the vitriol, be come over, the long- 
 necks 
 
Chemical Preparations. 169 
 
 necks are prevented, from holding the quantity 
 they would otherwife contain, by the greater 
 bulk, which the vitriol has in this ftate, than 
 when calcined. The nitre is likewife fubje<ft 
 to link to the bottom, when the vitriol is 
 melted into a fluid ftate -, as happens always, 
 in this cafe, from the water it contains ; 
 and this prevents fuch a due commixture, as 
 is neceflary ; in order that the acid of the vitriol 
 may ad: on the nitre, to feparate the fpirit from 
 it : and, for thefe feveral reafons, this procefs 
 has been greatly difufed of late. 
 
 But the college of London do not feem to have 
 greatly reformed thefe errors, of the old procefs 
 for the Angle aqua fortis, in the procefs given 
 laft by them for the double ; which, according 
 to the old manner of preparing it, was made by 
 means of vitriol calcined to rednefs. For, tho' 
 they have ordered part of the vitriol to be 
 ufed uncalcined, and part of it calcined to red- 
 nefs, as it were by mixing the two extremes to 
 find a remedy in each for the other 5 yet as 
 we fhall fee, on our remarks on this procefs, 
 inftead of removing thefe inconveniencs, they 
 have only added others. 
 
 Preparation of aquafortis, according to the 
 difpenfatory of the college of London. 
 
 Take, of nitre and green vitriol uncal- 
 cined, each three pounds 5 of the fame vi- 
 triol 
 
17© Chemical Preparations. 
 triol calcined to rednefs, one pound and a 
 half : mix them thoroughly ; and diftill 
 with a ftrong fire, as long as any red fumes 
 arife. 
 
 Note. 
 
 The principle, on which this alteration , or 
 rather combination, of the two proceffes, for 
 the fingle and double aqua fortis, is grounded, is 
 too myfterious to be underftood - y for, though 
 the proportion of phlegm, betwixt this mix- 
 ture of vitriol wholly uncalcined, and calcined 
 to rednefs, may not differ greatly from that of 
 vitriol calcined to whitenefs : yet, as in the 
 calcination to rednefs, a confiderable part of 
 the acid (as is obferved above,) being driven off, 
 to allow for which, the whole quantity of vi- 
 triol is here augmented, (the acid of the vitriol 
 being the medium, by which the Separation, is 
 made of the fpirit from the nitre), this occafi- 
 ons a greater confumption of the vitriol, and a 
 needlefs filling of the veflel in which they are 
 diftilled ; befides the inconveniences liable to 
 happen, from the boiling over of the uncal- 
 cined vitriol, and the feparation of the nitre 
 from it while melted, without the leaft con- 
 venience or faving to counterbalance thefe dis- 
 advantages. 
 
 It is, therefore, much better, when the me- 
 thod of making aqua fortis, by means of crude 
 vitriol, is followed (which, as I fhall {hew be- 
 low, maybe much better changed for another,) 
 
 to 
 
Chemical Preparations. 171 
 
 ufe the due proportion of vitriol calcined to 
 whitenefs, as is directed by the college of Edin^ 
 burg; and pra&ifed by thofe, who beft under- 
 ftand this art : by which not only the ebulli- 
 tion in the uncalcined vitriol, and tedioufnefs 
 of keeping back the fire with great care til] all 
 the phlegm be come over, are avoided ; but 
 the due commixture of the ingredients is 
 preferved, during the whole operation ; and 
 the quantity capable of being diftilled in the 
 fame veflel, confiderably augmented ; which, 
 in this cafe, enhances the profit in a very ma- 
 terial degree. But as the proportion of nitre is 
 much too great in the Edinburg procefs, the 
 following one, in which all thefe feveral errors 
 are reformed, and which is more conforma- 
 ble to the prefent praiflice of thofe, who carry 
 on this art as a manufa&ure, may be allowed 
 to be the beft hitherto given. 
 
 Improved procefs for the preparation of aqiia 
 forfis, from nitre and crude vitriol. 
 
 Take, of vitriol calcined to whitenefs, 
 and of crude nitre, each equal parts : 
 pound, and mix them well together : put 
 them into the iron pot, defcribed as part of 
 the apparatus for this purpofe, p. 47 ; and 
 fit on the head ; making good the joint 
 with fire lute ; the receiver being alfo luted 
 
 to 
 
172 Chemical Preparations. 
 to the arms : diftill with a fire increafed, 
 gradually, to the greateft degree ; and con- 
 tinued as long as any red fumes appear. 
 
 Note. 
 
 It will be proper here, and in all the diftil- 
 lations of fpirit of nitre, to leave a fmall hole, 
 made with a wire or pin, in the lute of the necks 
 of the receivers; in order to give a vent for the 
 air, generated by the adtion of the oil of vitriol 
 on the nitre ; and which, otherwife, will ftrain, 
 and open, the lute, to the annoyance of the 
 operator, and lofs of part of the fpirit. 
 
 Since the improvement, in the method of 
 obtaining it from fulphur, has fo greatly dimi- 
 nished the price of oil of vitriol, this method 
 of ufing crude vitriol, for the making of fpirit 
 of nitre, is rendered much lefs profitable, than 
 the obtaining it by means of the oil of vitriol. 
 And the making aqua fortis, by any method, 
 diftind: from that ufed for fpirit of nitre, is 
 alfo needlefsly troublefome : for, as the dif- 
 ference of them wholly confifts, in the addi- 
 tion of oil of vitriol to the other; when the 
 fpirit of nitre is obtained, the oil of vitriol may 
 be added to it, in any proportion found necef- 
 fary ; and it may be then extemporaneoufly 
 changed into any kind of aqua fortis ; and the 
 fame end confequently aniwered with greatly 
 lefs trouble and expence.^ 
 
 1 I 
 
Chemical Preparations. 173 
 
 I fhall, therefore, fubjoin the beft method of 
 procuring pure fpirit of nitre, by means of oil 
 of vitriol : which may be ufed, in that ftate, 
 by the refiners, gilders, &c. to whom the 
 purity is of the higheft confequence ; and com- 
 mixt with a due proportion of oil of vitriol, 
 for the ufe of the brafs founders, dyers, &c. 
 to whom this compound, or the aqua fortis, as 
 it is called, is necefiary, 
 
 Beft method of procuring pure fpirit of nitre, 
 for the purpofes of gilding, refining^ &c. 
 and which may be, likewife, on all occajions, 
 converted into any kind of aquafortis. 
 
 Take, of crude nitre, (called rough petre), 
 the white kind, twenty four pounds : put 
 it into a retort of a proper fize , and add 
 to it of oil of vitriol, twelve pounds : fit 
 on a very large receiver, firft pouring into 
 it fix pints of water : diftill them with a 
 fire gradually increafed to the higheft degree. 
 
 If the fpirit be required to be exceeding 
 ftrong, a pint or two of the water, dire£ted 
 to be put into the receiver^ may be left out. 
 
 Note. 
 
 This is the proper proportion of the oil of vi- 
 ■ triol to the nitre, for obtaining the fpirit of nitre, 
 
 in 
 
1^4 Chemical Preparations. 
 
 in the greateft degree of purify, in which it is 
 commonly had ; and which, in this ftate, is fit for 
 the ufes of the gilders and refiners : but as it is 
 very neceflary, for the folution of filver to make 
 the lunar cauftic, and for many other purpofes, 
 in arts and manufacturers, to have it perfectly 
 pure, I will here give the method, ufed by 
 the refiners, for that purpofe $ which at the 
 fame time fupplies the means of difcovering, 
 and remedying, the impurity of it in the moft 
 accurate degree. 
 
 Method of proving , and purifying^ the fpirii 
 of nitre. 
 
 Take a fmall quantity of fpirit of nitre J 
 diflblve in it as much filver, as it will take i 
 put a few drops of this into fome of the 
 fpirit of nitre, that is to be proved ; and, if 
 the fpirit remain tranfparent, it may be con-* 
 eluded to be pure; but, if a white cloudinefs 
 be perceived, which will afterwards form a 
 fediment, it may be, with certainty, in- 
 ferred, that there is fome commixture of 
 oil of vitriol,' or fpirit of fait, with it. 
 
 In order, therefore, to render the fpirit of 
 nitre abfolutely pure, drop the folution of 
 filver gradually into it, fo long as it fhall 
 
 produce 
 
Chemical Preparations. 175 
 
 produce the leaft turbidnefs 5 time being 
 given for the fpirit to become clear be- 
 twixt each addition : the fpirit of nitre, 
 being then poured off from the fediment, 
 will be perfedtly pure : and if this fediment, 
 which is the filver precipitated, be evaporated 
 to drynefs, and then fufed in a crucible, with 
 a fmall quantity of fixt alkaline fait of any 
 kind, it will be reduced to its proper metal- 
 line ftate. 
 
 Note. 
 
 By this method, fpirit of nitre may be ren- 
 dered, with very little trouble, or expence, of 
 an abfolute purity -, and fit either for the folu- 
 tion of filver, or any other experimental, or 
 ufeful purpofe, where fuch purity is neceflary : 
 but, as the commixture of a certain proportion 
 of oil of vitriol with it, is equally requifite for 
 fbme purpofes, as its being intirely free from 
 that acid is for others, I will fubjoin a fimple 
 method, of changing it into double or fingle 
 aqua fortis ; which, as we obferved before, are 
 only compofitions from thefe two acids. 
 
 Method 
 
176 'Chemical Preparations, 
 
 Method of converting pure fpirit of nitre into 
 double or jlrong aqua fortis, proper for the 
 ufe of founders , &c. in cleanfing brafs work 
 after it is cafi ; as alfo for engravers and 
 etchers of copper plates. 
 
 Take, of the pure fpirit of nitre, nine 
 pounds, of oil of vitriol, one pound : mix 
 them together* 
 
 Note. 
 
 The fpirit of nitre, if made exprefsly fof 
 this purpofe, may be prepared, with four- 
 teen pounds of oil of vitriol, inftead of twelve 
 to twenty four of the crude nitre : and, in this 
 cafe, only half a pound of the oil of vitriol muft 
 be added afterwards. 
 
 This is the only purpofe where double aqua 
 is neceflary : but, as the fingle is ufed on many 
 different occaiions, and particularly by the 
 dyers, in very great quantities, it is proper to 
 fhew, how it may be beft made from the pure 
 fpirit of nitre. 
 
 Method of converting the pure fpirit of nitre into 
 fingle aquafortis^ for the ufe of dyers > &c< 
 
 Take, of the pure fpirit of nitre, twenty 
 pounds, of oil of vitriol, feven pounds : 
 
 mix 
 
Chemical Preparations. 177 
 mix them well together \ and add of water 
 thirty pounds. 
 
 Note. 
 
 This mixture is particularly accommodated 
 to the purpofes of dyers : but, it will anfwer 
 extremely well, alfo, to thofe, who ufe fingle 
 aqua fortis, for mixing with water, in order to 
 the cleaning copper, or brafs work : and will 
 be found no way different from that diftilled 
 immediately from an equivalent proportion of 
 nitre and vitriol. It is, if made in the above 
 proportion, near the ftandard of the beft Dutch 
 aqua fortis, ufually fold to the dyers : but that 
 may be eafily regulated, if there be occafion 
 to make it correfpond with any fixt price, by 
 the reducing it lower by the further addition 
 of water : and it may be compared, accurately 
 enough, with any other, by means of their 
 fpecific gravity; which may be found, by fill- 
 ing a fmall glafs globe, having a narrow neck, 
 with each kind ; and obferving their agree- 
 ment, or difference, on weighing them in a 
 pair of fmall fcales. 
 
 By this treatment of the aqua fortis, it may 
 be afforded, with confiderable profit, at a much 
 lower rate than it is fupplied from Holland : 
 efpecially by thofe, who manufacture the oil 
 of vitriol themfelves, according to the new 
 method : or it will very well anfwer for dyers, 
 or others, who ufe great quantities to make 
 what they ufe themfelves, (which, according 
 
 N to 
 
178 Chemical Preparations. 
 
 to the procefs above given, may be managed 
 in a very fmall compafs) : particularly, while 
 oil of vitriol fhall continue at the low price of 
 four pence per pound. 
 
 Spiritus nitri dulcis, or dulcified fpirit of 
 
 nitre. 
 
 Take, of rectified fpirit of wine, two 
 pints, of Glauber's fpirit of nitre, (that is 
 to fay, the kind made with oil of vitriol) 
 half a pound : mix them, by pouring the 
 fpirit of nitre on the other ^ and diftill the 
 mixture, with a gentle heat, as long as what 
 comes over will not raife any fermentation 
 with alkaline falts. 
 
 Note. 
 
 The proportion of half a pound of the 
 fpirit of nitre, to two pints of the fpirit of 
 wine, is much too great : for, as it is parti- 
 cularly intimated, by the caution, not to fuffer 
 the remaining fpirit of nitre to rife after the 
 fpirit of wine be come over, that redundant 
 acid is injurious to the dulcified fpirit, it is, con- 
 fequently, unneceffary to ufe more than the 
 quantity of fpirit of wine can carry over with 
 it \ which will be lefs than half this propor- 
 tion': and this diminution of the quantity will 
 fuffer the whole to be drawn over, without the 
 
 trouble 
 
/Chemical Preparations, 179 
 
 trouble of watching the critical point -, or 
 making experiments with alkaline fait. 
 
 It is neceflary to be extremely cautious, in 
 making the dulcified fpirit of nitre,, as well that 
 as of vitriol, in mixing the ingredients together: 
 elpecially, if the fpirit be highly rectified : for 
 an explofion frequently happens ; particularly, 
 when near the whole quantity of fpirit of nitre 
 has been added to the other. It is beft, there- 
 fore, to put in only very fmall quantities at. a 
 time ; and to let the mixture ftand, after each 
 addition of the fpirit of nitre, till no heat ap- 
 pear to remain 5 or even to arife on fhaking the 
 veflel. 
 
 The diftillation of dulcified fpirit of nitre is 
 beft performed in retorts, placed in the cooleft: 
 part of the land -bath, with very large receivers 
 fitted into them. 
 
 The dulcified fpirit of nitre is very frequently 
 adulterated with water, from which the unfo- 
 phifticated may be befi: diftinguifhed, by the 
 ftrength of that peculiar and grateful fcent, 
 this composition has, when duly prepared ; 
 and which is always proportionably abated by 
 any addition of water ; and almoft wholly de- 
 ftroyed, when lowered beyond that degree of 
 ftrength, called proof, in the fpirit of wine. . 
 
 Sal primellce. 
 
 Take any quantity of falt-petre : melt it 
 in an earthen pot, or clean iron kettle : 
 
 N 2 when 
 
i8o Chemical Preparations. 
 when it is well melted, caft a little of the 
 flowers of fulphur upon it ; and, when that 
 is burnt, put on more •, and continue to do 
 fo, till the nitre flow as clear as rock water, 
 without any fcum : then, with a clean iron, 
 or brafs ladle, take it out of the pot ; and 
 put it into a warm brafs pan or mold : 
 when that is fixed, put it by 3 and, with the 
 ladle, take out more, till the melted fait 
 be all caft ; which keep for ufe. 
 
 Note. 
 
 This is the old procefs for fal prunellae. 
 The Edinburg college have fixed the propor- 
 tion of fulphur to be one ounce to two 
 pounds ; which makes the medicine, then, a 
 compound of two falts : for the greateft part 
 of the nitre will be left unchanged - y and mixed 
 only with fo much of a new fait, as that pro- 
 portion of fulphur could ad: upon, and convert 
 into one. 
 
 In the above procefs, by melting, muft be 
 underftood the fufion of the nitre ; as no fluid 
 is to be added to it to diflblve it : and, as this 
 requires more than the firft degree of red-hot 
 heat, earthen pots will be fcarcely found able 
 to endure fo ftrong a fire, without cracking ; 
 and, as to the iron kettle, I do not fee how that 
 can be conveniently put into the fire : befides, 
 
 that 
 
Chemical Preparations. 181 
 
 that the nitre, before the fulphur be added to 
 it, will calcine the iron, or any other metal, 
 except gold or filver, by deflagrating with the 
 fulphur contained in it. It is, therefore, better, 
 to perform this operation in a large crucible. 
 
 When fal prunella is made with the pro- 
 portion of fulphur above dire&ed, it is, as I 
 have fhewn before p. 82, exactly the fame 
 with the vitriolated tartar, fal polychreftum, 
 and fal enixum ; that is to fay, it is a neutral 
 fait, formed from fixt alkaline fait, and the acid 
 of vitriol. As thefe falts are, therefore, all the 
 fame, except, as to the different method of ob- 
 taining them, that, which can be cheapeft pro- 
 cured, may be fubftituted for the other; and 
 the caput mortuum, after the diftillation of 
 fpirit of nitre, by means of oil of vitriol, may 
 be formed into fal prunella as well as tartar 
 vitriolate, by a proper change of the method -, 
 which may be the following. 
 
 Method of forming fal prunella from the fal 
 enixum , or caput mortuum^ ajter the dijlil- 
 lation of fpirit of nitre ^ made with oil of 
 vitriol. 
 
 Take any quantity of the fal enixum, or 
 caput mortuum left after the diftillation of 
 the fpirit of nitre -, and, if it be acid, add 
 to it a fmall quantity of fixt alkaline fait : 
 
 N 3 put 
 
1 82 Chemical Preparations. 
 
 ■ 
 
 put it into a crucible ; and give it a heat fuf- 
 ficient to fufe it, or make it run into a fluid 
 ftate : but if, on trying, in this ft ate, it 
 yet appear acid, more of the fixt alkaline 
 fait may be added, till no acidity remain. It 
 muft be then caft into molds -> or, what is 
 more convenient, poured out, by fmall ladle- 
 fulls, on a fmooth copper, or iron plate , 
 which will form it into thin cakes ; fuch as 
 are ufually feen in the fhops. If any brown 
 colour appear in it, a little nitre may be 
 added to it, while in this flate of fufion ; 
 which will bring it to perfect whitenefs. 
 
 Note. 
 
 If the fal prunelke be defired, to be fuch a 
 compound of the two kinds of falts, as the 
 procefs of the Edinburg college feems to in- 
 timate to be proper, a proportion of nitre may 
 be added at pleafure to this fait, while in 
 a ftate of fufion, which will effedt the fame, 
 as if the fal prunellas were made from nitre 
 and fulphur, in an equivalent proportion. 
 
 Sal pclychrefl. 
 
 Mix equal parts of fulphur and nitre, in 
 fine powder ; and put them into a red-hot 
 
 crucible, 
 
Chemical Preparations. 183 
 crucible, by a fpoonful at a time ; obferving, 
 as foon as the explofion caufed by one fpoon- 
 ful be over, to put in another ; and conti- 
 nuing to do fo till all the mixture be ufed : 
 put then a tile over the top of the crucible ; 
 and, covering the whole over with coals, 
 keep the fait in fufion four or five hours : 
 then pour it into a warm copper veffel; 
 and, when cold, powder and diffolve it Hi 
 warm water : filter the folution 5 and eva- 
 porate till it be dry. 
 
 If this fait be not fo white as defired, put 
 it again into a crucible 5 and fet it in a 
 flrong fire for three or four hours longer ; 
 continually ftirring it till it be very white : 
 then again diffolve, filter, and evaporate to 
 drynefs." 
 
 Note. 
 
 This is the common procefs for making this 
 fait : but it is not a very good one. The keep- 
 ing this fait in fufion fo long is wholly unnecef- 
 fary ; for it is properly formed as foon as the 
 explofion ceafes. 
 
 The forming this fait into chryftals is wrong- 
 ly omitted : for, if it be required only in a dry 
 mafs, improper fubftitutions .will be fold in its 
 place; againft which, the particular appearance 
 
 N4 of 
 
1S4 Chemical Preparations. 
 
 of the chryffcals, when once known, is a fe- 
 curity. Bat, as, probably, fuch fubftitution 
 will be the unprepared caput mortuum, after 
 the diftillation of fpirit of nitre, it may be 
 diftinguifhed by its acid tafte j which fhould be 
 wholly wanting in the fal polychreft. 
 
 As this, no ways, differs from the tartar vi- 
 triolate, it is unneceflary to repeat here again, 
 in what manner it may be moft profitably and 
 perfedtly prepared ; as, what is before laid on 
 that article, may be confulted with regard to 
 this. 
 
 Sal mirabiky or Glauber s fait. 
 
 Take, of clean fea fait, fountain water, 
 and oil of vitriol, each two pounds : mix 
 the oil of vitriol, with the water, thus. Firfl 
 put the water into an earthen veffel ; then 
 put the oil of vitriol to it, by two or three 
 ounces at a time ; for, if more be put in 
 together, it will endanger the breaking of 
 the veffel, by the violence of the heat that 
 will be produced : put, then, the fait into a 
 retort, fet in a fand-pot 5 and add the oil, 
 and water, to it ; fit on -a receiver, and 
 diftill with a fire gradually increafed to the 
 greateft degree. Take the fait left in the 
 retort after the diftillation } and diffoive it 
 
 in 
 
Chemical Preparations. 185 
 in water : filter, evaporate to the due point, 
 and fet the folution, to form chryftals, in a 
 cold place. 
 
 Note. 
 
 This is the old procefs for Glauber's fait. 
 The college of London have reduced the quan- 
 tity of water to one half; which is very pro- 
 per : becaufe the real ufe of it, being only 
 to render the fumes of the fpirit of fait more 
 condenfible, a redundant quantity only pro- 
 trails the operation, by making a longer diftil- 
 lation neceffary. 
 
 The college of Edinburg have diminished 
 the quantity of oil of vitriol to one half; which 
 is, certainly, a much better proportion than that 
 of the college of London. With relpeft to the 
 quality of the Glauber's fait produced, it is 
 wholly indifferent what quantity of fea fait is 
 ufed ; but, with refpe<ft to profit and expe- 
 dience in the operation, it is far otherwife : 
 for, if the quantity of oil of vitriol be greater, 
 than is fufficient to expel the acid of the fait, 
 it will require a great degree and continuance 
 of fire, to drive it over ; and, when the fait is 
 freed from it, as well as it can be, by the heat 
 of a fand furnace, it will render the folution fo 
 acid, that the chryftals will take a very long 
 time in drying ; and be themfelves too acrid, 
 from the acid which will remain with them, 
 for the intention of the medicine. The beflr 
 proportion, therefore, that can be fettled, is, 
 
 by 
 
i86 Chemical Preparations* 
 
 by adjufting the quantities in fuch manner, 
 that there may be a fmall quantity more of the 
 oil of vitriol than can be fixed by the alkaline 
 balls of the fea fait ; which, according to the 
 prefent ftandard of oil of vitriol, is about 
 nine ounces of the oil of vitriol to a pound of 
 the fea fait : and, if the Glauber's fait produced 
 ihould not fhoot freely, as will fometimes hap- 
 pen, if the folution be wholly void of acid, a 
 little oil of vitriol may be added ; which will 
 certainly anfwer that purpofe the fame, as if 
 it came out of the retort with the fait. 
 
 The ufe of an earthen veffel, in the above 
 procefs, is wrong : for all earthen veffels make 
 a wafte of fluids put into them, if they be not 
 glazed ; and fuch as are lb, are liable to have 
 the glazing immediately corroded and eaten 
 off, when acid fpirits of any kind are put into 
 them. 
 
 This medicine, though of great importance 
 in practice, was, for feveral years, almoft ex- 
 cluded by the fubftitution of a counterfeit kind, 
 made firft at Limington, and afterwards elfe- 
 where; of which, I fhall fpeak more particularly 
 below : but the ufe of this counterfeit, being 
 in its turn fuperfeded greatly by the late im- 
 provements made in the preparation of the 
 genuine kind, and the eafy method of obtain- 
 ing oil of vitriol from fulphur, by which they 
 have reduced the wholefale price even to four 
 pence per pound, I will (how the mofl expedite 
 and cheap methods, by which, the true kind 
 is^ ''or may be made. 
 
 2 MqJI 
 
187 Chemical Preparations. 
 
 Moji profitable and eafy method of preparing 
 the true Glauber s falts> by means of the ap~ 
 par at us defcribed p. 33. 
 
 Take, of fea fait, twenty four pounds % 
 and put it into a retort of a proper lize : 
 add to it, of oil of vitriol, fourteen pounds, 
 mixed, very gradually, in a glafs receiver, 
 with ten or twelve pints of water : fet the 
 retort in a fand-pot ; and let it ftand 
 there for fome hours the mouth being- 
 flopped with paper : diflill then, with a 
 heat gradually raifed to a pretty ftrong 
 degree, till no more fumes come into the 
 receiver : after the furnace is properly 
 cooled, take the cake of falts out of the 
 retort ; and diffolve it, in boiling water, in 
 cafe of very large quantities in the leaden 
 boiler defcribed p. 33, or, other wife, in a 
 large pipkin of flone ware : filter the folu- 
 tion through earthen cullenders ; and put 
 it either in the leaden vefiels, or large 
 receivers, above defcribed : and let it ftand 
 to fhoot. After the chryflallization is fi- 
 nifhed, which muft be concluded from the 
 
 chryflals 
 
1 88 Chemical Preparations.* 
 chryflals not appearing to grow bigger, 
 the mothers (or fluid remaining after the 
 fhooting of the falts) muft be poured off 
 from the falts in the receivers ; and the falts 
 fet to drain in the earthen cullenders, or 
 proper bafkets -, or, if in the leaden cittern, 
 they muft be taken out into the baikets, 
 provided for this purpofe; and, when drained 
 there to a proper degree, laid on the frame 
 of baiket work to dry. 
 
 Note. 
 
 . By this method, if the oil of vitriol continues 
 at the very low price, for which it is fold at pre- 
 fent, the true Glauber's fait may be made at fo 
 cheap a rate, that one may hope to fee intirely 
 rejected the counterfeit kind, known, among the 
 dealers in medicine, by the name of the Lym- 
 ington falts, and fold in the fhops under the 
 name of Glauber's fait -> of which name, the 
 genuine kind was fo much robbed, that it was 
 diftinguifhed from this by the name of fal 
 mirabile : but, as there yet remains fome de- 
 mand for them, either amongft thofe, who 
 are ignorant of the real difference betwixt them 
 and the true kind, or who are induced, by fome 
 fmall advantage in the price, to prefer them, I 
 fhall fliow what they really are ; and how con- 
 verted into that form, which makes them pafs 
 for the genuine kind. 
 
 Method 
 
Chemical Preparations, 189 
 
 Method of producing the Lymington> or coun- 
 terfeit Glauber s fait s, from the fal cathar- 
 ticam amarum, or Epfom fait, as it is called 
 in the jhops. 
 
 Take the Epfom fait, (which is the fal 
 catharticum amarum, ftiot into chryftals 
 from the bittern, or mothers of the fea fait, 
 when obtained from fea water) ; and diffolve 
 it in boiling water : put it into proper vef- 
 fels ; adding, to every gallon of the folution, 
 an ounce or more of oil of vitriol : let the 
 chryftals form ; and then take them out, 
 and dry them. This may be done, alfo, 
 with the bittern itfelf ; and the counterfeit 
 Glauber's fait produced, without any pre- 
 vious formation of them into the fidlitious 
 Epfom fait. 
 
 Note. 
 
 The fai catharticum amarum, treated in this 
 manner, refembles greatly the appearance of 
 the true Glauber's fait j and, as it is to be obtain- 
 ed, in very great quantities, from the mothers, 
 (or fluid remaining .after the chryftallization 
 of the fea fait, when made from fea water,) 
 by this fimple and cheap procefs, it was fold 
 
 for 
 
190 Chemical Preparations. 
 for fo low a price, that the ignorant and greedy 
 traders in medicine foon received it, after its 
 firft invention, in the place of the genuine fal 
 mirabile : the ufe of which, it almoft excluded, 
 till the later improvement reftored it by reduc- 
 ing the price nearly to a level with this. As 
 this counterfeit is, however, in no degree com- 
 parable to the true kind as a medicine, being 
 naufeous to the flomach, and apt to produce 
 a violent ficknefs and gripings, I will give an 
 infallible method of diftinguifhing the one 
 from the other : that they, who are defirous, 
 may not have this fubftitution impofed upon 
 them, through ignorance of the means of dis- 
 covering when it is attempted. 
 
 Method of diftinguijlnng the Lymingto?i> or 
 counterfeit : , Glauber s fait, from the true 
 kind. 
 
 Take, any quantity of the fufpected ialt ; 
 and diflblve it in clean water : and, when the 
 folution is become clear, and limpid, add to 
 it a fmall quantity of the folution of fait of 
 tartar, or any other fixt alkaline fait, made- 
 clear likewife : if no change happen on the 
 commixture, but the mixt folutions conti- 
 nue to be as clear and tranfparent as when 
 feparate, it may, with certainty, be con- 
 cluded, 
 
Chemical Preparations. 191 
 eluded, that the fait, thus examined, is the 
 true Glauber's fait : but, if a milky tur- 
 bidnefs appear, which will afterwards be 
 fucceeded by the precipitation of a powder, 
 it may thence be known to be the Lyming- 
 ton counterfeit. On the want of fixt alka- 
 line fait, to make this experiment, volatile 
 fait may be ufed, in its place, with the fame 
 
 effeft. 
 
 Note. 
 
 By this method, the true fai mirabile may 
 be always known from this counterfeit, by thofe 
 who are unaquainted with either kind : but 
 thofe, who are more converfant with matters 
 of this nature, may ealily diftinguifh them 
 from each other, by a bitter ftyptic tafte, which 
 the Lymington fait has in a much greater de- 
 gree than the other ; and by the form of the 
 chryftals ; which in the true Glauber's fait are 
 longer, and more of the figure (as it were) of 
 long fquare needles. 
 
 Magnejia alba. 
 
 Take, any quantity of the mothers, or 
 fluid remaining, after the chryflallization of 
 the falt-petre, in the refinement of crude 
 nitre : add to them, gradually, a folution 
 
 of 
 
192 Chemical Preparations* 
 of fixt alkaline fait, as long, as any effer- 
 vefcence, or white turbidnefs, appear to be 
 produced- By thefe means, a white pow- 
 der will be precipitated : which, being fe- 
 parated from the fluid, freed from the re- 
 maining fait by wafhing, and afterwards 
 dryed, is the original magnefia alba. 
 
 Note. 
 
 This is the true and original procefs, by 
 which the magnefia alba of Hofman was 
 made : but, as very little earth is to be ob- 
 tained from nitre, other precipitations have 
 been made from fubftances, which afford 
 it copioufly ; and have been fubflituted in 
 the place, and wholly excluded the ufe, of 
 this. That, which has moil commonly been 
 pra&ifed, is as follows. 
 
 Method of making the jiBitious magnejta alba% 
 which is the only kind ufed here. 
 
 Take, of the fal catharticum amarum, or 
 Epfom fait, any quantity : diffolve it in wa- 
 ter: difTolve, alfo, half the fame weight of 
 pearl afhes ; and filter the folution. Add 
 the folution of pearl afhes to that of the 
 Epfom fait j at firft in pretty large quanti- 
 ties, 
 
Chemical Preparations. 193 
 ties, but afterwards more gradually, fo long 
 as any effervefcence, or turbidnefs, appear to 
 enfue the admixture. After the powder, 
 which will be, by this means, precipitated, 
 has wholly fubfided to the bottom, and the 
 fluid be become clear, decant off, all that can 
 be feparated, from the powder; and put the 
 remainder, together with the powder, into 
 an earthen filter, with paper, and a linnen 
 eloth over it : when the fluid is thus fur- 
 ther feparated from it, and it is become of 
 a proper confiftence, lay the powder on a 
 board, or chalk ftone, to dry. 
 
 Alum has been, alfo, ufed inftead of the 
 Epfom fait ; and will afford a white earth, 
 by the fame treatment : but the two earths 
 are very different in their nature. 
 
 Note. 
 
 This is the procefs, by which the magnefia 
 alba, fold here during the vogue, in which this 
 medicine was fome time ago, was prepared, by 
 fome confiderable dealers in drugs and chemi- 
 cal preparations, who pretended they imported 
 it from Hamburg. This earth is not the fame 
 with that obtained from the nitre: but, for any 
 thing that appears to the contrary, may anfwer 
 the fame end ; as it is, by no means, evident, 
 
 O there 
 
194 Chemical Preparations. 
 there is any efficacy in either, which does folely 
 lie in the alkaline quality, they poffefs, in com- 
 mon with all other cetaceous or teftaceous 
 bodies. 
 
 As the magnefia alba has been recom- 
 mended, as having a cathartic power, on chil- 
 dren, along with that of abforbing acids, it is 
 better not to free the earth from the falfe, formed 
 in the preparation, by any fubfequent additions 
 of water to it in the filter : for the fait pro- 
 duced, being the fame with the fal polychreft, 
 vitriolated tartar, &c. will contribute to the ca- 
 thartic effedt : or, indeed, muft be the only caufe 
 of it ; unlefs where the earth, meeting with a 
 confiderable quantity of acid, in the inteftines 
 of thofe, who take it, may be converted into 
 a neutral fait; which will, confequently, have 
 this power* 
 
 Spirit of fulphur by the bell. 
 
 Take any quantity of fulphur ; put it 
 into an earthen difh, placed upon an in- 
 verted crucible : fet them both, upon the 
 bottom of a large earthen veffel, in a moifi 
 place, fecured from the wind ; and then 
 fire the fulphur with a red-hot iron ; and 
 hang over it a glafs bell, at fuch a diftance 
 as to be out of the reach of the flame ; the 
 vapour of the fulphur will condenfe in the 
 
 belli 
 
Chemical Preparations, 195 
 bell > and flow down the fides of it, like 
 water, into the veffel underneath. 
 
 Note. 
 
 The fpirit, thus obtained, will no way differ 
 (as was before fhewn p. 80) from pure oil of 
 vitriol of the fame flrength : and the acid, now 
 fold under that name, is, (as we have before 
 feen,) prepared from fulphur by parallel means. 
 But, as the college of London have thought 
 proper to give this procefs; and, thereby, feem 
 to intimate, the fpirit of fulphur, by the bell, 
 may be efteemed a different medicine, and, as, 
 many from that authority, or their own at- 
 tachment to former ufages, may chufe to have 
 fpirit of fulphur prepared in this manner, I 
 fhall fubjoin a much more expedite and pro- 
 fitable method than the above, for conducing 
 this procefs, by increafing the quantity of con- 
 denfing furface ; and by determining all the 
 fumes of the fulphur to pafs into the con- 
 denfing veffel ; both which are wanting, when 
 the common bell is ufed. 
 
 An expedite and profitable manner of making 
 the fpirit of fulphur by the bell y by means of 
 the apparatus defer ibed p. 48. 
 
 Put the glafs plate over the mortar \ and fet 
 the drinking glafs, inverted, in the middle of 
 
 O 2 it: 
 
196 Chemical Preparations. 
 it : put, then, a proper quantity of fulphur in- 
 to the fmall earthen difh ; and place it on the 
 bottom of the inverted glafs : fufpend the 
 retort, over thefc other veffels, in fuch man- 
 ner, that the plate, containing the fulphur, 
 may be put within the hole in the bottom of 
 the retort ; fpace being left for the air to 
 enter freely, on every fide the difh, into the 
 cavity of the retort. The tubulated re- 
 ceiver muft be then fitted to the retort, and 
 the joint luted : after which the fulphur 
 muft be fired ; and the fumes will be con- 
 denfed into fpirit $ partly in the retort, 
 which will drop thence on the plate, and 
 run into the mortar; and, partly, in the 
 receiver. When the quantity of fulphur 
 in the difh is confumed, it muft be re- 
 newed ; or, if, by accident, its fire be ex- 
 tinguifhed before the whole be burnt away, 
 it muft be rekindled by means of a red-hot 
 iron. 
 
 Note. 
 
 Thofe, who are follicitous to have the fpirit 
 of fulphur prepared by the regular procefs, may 
 eafily procure it by thefe means : but it is not 
 to be expe&ed from (hops or dealers j the oil 
 
 of 
 
Chemical Preparations, 197 
 
 of vitriol, diluted with water, being univer- 
 fally fubftituted for it : and, as they are, ex- 
 cepting accidental impurity, the fame, there is 
 no way of diftinguifhing the one from the 
 other. 
 
 Lac falphuris. 
 
 Take, of fulphur, any quantity, of quick- 
 lime, thrice the weight of the fulphur : 
 boil them, till the fulphur be difTolved; and 
 filter the folution through paper : make a 
 precipitation with weak fpirit of vitriol; 
 which precipitation is to be made perfectly 
 infipid by frequent walhings. 
 
 Note. 
 
 This is the procefs of the college of Lon- 
 don ; and diredts a much cheaper and fhorter 
 method, than the old one of ufing fait of tar- 
 tar inftead of the lime. 
 
 It is, however, erroneous, with refpedt to 
 the quantity of lime : as half the quantity, 
 there prefcribed, or lefs, will be fufficient to 
 caufe the folution of the fulphur ; with which 
 intention alone, the lime is ufed ; and, as, by thus 
 increafing the volume of the feces, (which the 
 lime may be allowed to be called, after it has 
 anfwered its purpofe, in making the water dif. 
 folve the fulphur), the filtration of the folution 
 
 O3 is 
 
198 Chemical Preparations. 
 is rendered very tedious ; and attended with a 
 considerable lofs, from the quantity of fluid, 
 which remains abforbed, in the great mafs of 
 lime, after it has been as well drained, as it can 
 be in any moderate time. The following pro- 
 cefs, therefore, may be confidered as preferable 
 to the above. 
 
 Improved method of preparing the falfiilphnris. 
 
 Take, *of quicklime, feven pounds : put 
 It, gradually, into a proper boiler, contain- 
 ing three or four gallons of water : when the 
 lime is quenched in the water, add to them, 
 of crude fulphur, five pounds : and boil the 
 mixture three quarters of an hour, or an 
 hour : the fulphur being, then, difTolved in 
 the water, filter the folution, through paper, 
 in an earthen cullender ; and, when the 
 fluid is fo drained from the lime, that the 
 filter ceafes to run freely, put water to it, 
 in the filter, to drive through as much more 
 as poflible of the remaining part of the fo- 
 lution. To the folution, thus feparated 
 from the lime, add oil of vitriol, or fpirit of 
 fait, very gradually, as long as it fhall ap- 
 pear to have any e£Fe£t on the fluid, by ex- 
 citing any effervefcence, or producing any 
 
 turbid- 
 
Chemical Preparations. 199 
 turbidne-fs 5 and when the powder, which 
 will be, by this means, precipitated, has fub- 
 fided to the bottom of the veflel, take away 
 as much of the fluid, as can be poured off 
 clear, by decantation ; and free the powder 
 from the remaining part > by filtering with 
 the earthen cullender through paper, a lin- 
 nen cloth being put over the paper : when 
 all the fluid has drained from the powder in 
 the filter, put it into a quantity of frefh wa- 
 ter ; arid proceed, by decantation and filter- 
 ing, as with the firfi quantity of fluid, till 
 the powder be a fecond time freed from all 
 the fluid, except what its own mafs abforbs : 
 fill up the filter, then, with frefh water; and, 
 when that is drained off, repeat the fame : 
 after which, lay the mafs to dry, on a pro- 
 per board, in fmall pieces. 
 
 Note. 
 
 By purfuing this method, more lac fulphuris 
 will be obtained, from any quantity of crude 
 fulphur, than when a greater proportion of lime 
 is ufed: and the wafhing it, in this manner, will 
 free it from the falts effectually. It is, how- 
 ever, very ufual to omit the wafhing : by which 
 omifiion, not only fo much trouble is fpared, 
 
 O 4 but 
 
200 Chemical Preparations. 
 
 but a gain arifes from the falts left behind, as 
 they add to the weight : but this negleft may 
 be eafily perceived, by a roughnefs, that ap- 
 pears, from it, in the lac fulphuris, on its being 
 rubbed betwixt the fingers ; as, alfo, by the a- 
 bundance of fhining particles, which may be 
 fcen in it. 
 
 It is too common, likewife, to adulterate this 
 medicine by chalk, lime, calcined oyfler-fhells, 
 or other cretaceous bodies : which fophiftica- 
 tion, or any other, by heterogeneous matter, 
 may be detected by the following means. 
 
 Method of dif covering the fophijli cation of lac 
 fulphuris. 
 
 Take any quantity of the lac fulphuris, 
 that is fufpe6ted ; put into a crucible -, and 
 put a lefs crucible, reverfed, on the other, as 
 a cover, but without any lute : place them 
 in a common fire, where there is a fufficient 
 heat to fublime the fulphur : continue them 
 there, till the fulphur be wholly fublimed ; 
 which may be perceived by the fumes ceafing 
 to arife. If the lac fulphuris be pure, there 
 will be no recrement, or caput mortuum, 
 left in the crucible : but, if there be any adul- 
 teration, the matter of it will be left in the 
 crucible 3 and, by weighing, or other proper 
 
 trials. 
 
Chemical Preparations. 201 
 trials, either its quantity, or nature, may be 
 known. 
 
 Salt of amber. 
 
 Take, of white amber, one part, of clean 
 fand, three parts : being mixt, put them in- 
 to a glafs retort, of which they will fill one 
 half : then fit on a large receiver : and 
 diftill, in a fand-heat, with a fire gradually 
 increafed : at firft a fpirit will come over, 
 with fome yellow oil ; then a yellow oil ; 
 after which, the heat being increafed, more 
 fait will rife, with a redifh oil: when the 
 diftillation is over, empty the fluid out of 
 the receiver -, and, having colledted the fait, 
 which adheres to the'fides, dry it by a gen- 
 tle preffure betwixt the folds of fpongy pa- 
 per* The oil may be feparated from the 
 fpirit, by filtering ; and afterwards re£tified, 
 by diftilling it from fome brine of fea fait. 
 
 Note. 
 
 This is the procefs of the Edinburg difpen- 
 fetory ; and the beft, upon the whole, hitherto 
 given : but it is, neverthelefs, improper in fome 
 particulars 5 and too inexplicit as to others. 
 
 The 
 
2a2 Chemical Preparations, 
 
 The addition of fand, in the diftillation, is 
 unneceffary, and better omitted : for the only 
 ufe of it, is to keep the melted amber from 
 rifing over the neck of the retort : but a too 
 great ebullition may be eafily avoided, by the 
 proper management of the fire; without which, 
 the fand itfelf will fail in preventing this confe- 
 quence. 
 
 The infifting on white amber, is without any 
 ground : for, though that fort be generally dearer 
 than the other, yet the blacker kind fometimes 
 affords an equal, or greater quantity, of fait ; 
 and is, in other refpe&s, exactly the fame with 
 relation to this preparation. The great fecret 
 in preparing this medicine cheap, does, indeed, 
 lie in the choice of the amber ; as fome par- 
 cels afford, greatly, more fait than others : but 
 this difference is not difcovered, either by the 
 colour, or any other apparent quality, hitherto 
 known : on which account, the beft way is, 
 to try, by a moderate quantity, what any par- 
 cel will afford ; and to purchafe the whole, if 
 it be found good s orotherwife to reject it, and 
 try fome other. 
 
 The retorts ufed, for this operation, fhould be 
 made with long wide necks, cut to a very large 
 orifice $ that the fait may be taken out before 
 the brown oil arife ; which may be done by a 
 fmall wooden fpatula. 
 
 The fait, which comes after, along with the 
 brown oil, may be put into the phlegm, that 
 is improperly called the fpirit, (being only wa- 
 ter impregnate with the fait) : and, this phlegm, 
 
 being 
 
Chemical Preparations. 203 
 
 being freed from the oil, and afterwards ex- 
 haled, in balneo marise, the remaining fait 
 may be mixed with that, which was at firft 
 taken out of the neck. 
 
 The college of London, in their difpenfa- 
 tory, dired: the fait to be boiled, either in the 
 fpirit, which comes over with it, or in water; in 
 order to free it, more effeftually, from the oil 
 adhering to it; and even feems to intimate a 
 repetition of this operation : but, as this caufes 
 an additional trouble in diflblving the fait, and 
 evaporating the fluid, to bring it back to a pro- 
 per form ; and tends, alio, to a diminution of 
 the quantity, as well by taking away the oil, 
 as by the wafte, which this treatment will un- 
 avoidably occafion, it is feldom praftifed : and, 
 with regard to the perfeftion of the medicine, 
 the omiffion of this part of the preparation is, 
 perhaps, rather meritorious, than condemna- 
 ble : for it is a great queftion, whether the fait 
 of amber does not owe a principal fhare of its 
 efficacy, to the oil, which is mixt with it ; and, 
 certainly, if fo, the cleanfing it, more than is 
 done by means of fpongy paper, may be ra- 
 ther a detriment than an improvement. 
 
 The fait of amber, being a very dear me- 
 dicine, is very frequently adulterated : and the 
 moft ufual fubftances, with which it is fophifti- 
 cated, are cremor tartaris and fal ammoniacum. 
 
 But thefe frauds, or, indeed, any other, com- 
 mitted on this medicine, are eafily deteftable, 
 by the following means. 
 
 2 Method 
 
204 Chemical Preparations. 
 
 
 Method of detecting any adulterations of the 
 fait of amber. 
 
 Take a fmall quantity of any parcel fu- 
 fpe6ted ; and mix it with moift foap, of any 
 kind. If it be adulterated with fal ammo- 
 niacum, a fmell of volatile fait will imme- 
 diately be difcernible : from whence the 
 fophiflication, with the fal ammoniacum, 
 may be pofitively afcertained. 
 
 If it ftand this trial, and no pungency, 
 like that of volatile falts, enfue, take ano- 
 ther fmall quantity ; and lay it on a poker, 
 heated almoft red-hot : by which means, 
 the fait of amber will be diffipated in fumes ; 
 and the heterogeneous matter left behind : 
 which, if it be cremor tartaris, will appear 
 in the form of a black or coaly powder > if 
 any other neutral fait, in a white one. 
 
 Note. 
 
 Thefe two experiments are fully conclusive, 
 with refpeft to the genuinenefs of fait of am- 
 ber ; for it can be adulterated with nothing, that 
 has a volatility in a degree near its own, except 
 ammoniacal falts, which will, always, fhew 
 
 itfelf, 
 
Chemical Preparations.* 205 
 
 itfelf, by the appearance of a volatile pungency, 
 on its admixture with the folution of fixt alka- 
 line fait, either in foap, or any other way : and, 
 if it be not adulterated with fome body vola- 
 tile, like itfelf, the application of that degree of 
 heat, which will fublime it, will, confequently, - 
 feparate it from the fophifticating matter ; and 
 leave fuch matter, fubjedt to any further exa- 
 mination, which ihall be thought proper. 
 
 Oil of amber. 
 
 Take any quantity of the oil, as it comes 
 over, in the diftillation of the amber for 
 the fait 5 and put it into a retort, with 
 four times its weight of water : fit a large 
 receiver to the retort \ and give a heat, juft 
 fufficient to keep the water boiling : con- 
 tinue the diftillation, till a great part of the 
 mixture be come over : when, the receiver 
 being taken away, the rectified oil muft be 
 feparated from the water. If the oil of am- 
 ber be defired very limpid, the ratification 
 muft be repeated. 
 
 Note. 
 
 The Edinburg college dired: this operation 
 to be performed with brine of fea fait : but 
 water will anfwer the end equally well ; if the 
 
 heat 
 
206 Chemical Preparations. 
 heat be kept from rifing above the due degree % 
 and the retort be made of a long form, having 
 its neck placed fo depending in the furnace, as 
 to return a great part of what is condenfed in 
 it again into the body of the retort. 
 
 Though the oil of amber be thrown away 
 in great quantities, by thofe, who make the 
 fait ; yet, to avoid the trouble of the rectifica- 
 tion, it is very ufual to adulterate it by the ad- 
 mixture of the oil of turpentine : which it is 
 very difficult to difcover, unlefs by the fmell. 
 It is, however, a blameable practice -> and ought 
 to be guarded againft ; as the oil of amber has 
 medicinal qualities different, at leaft in the 
 degree, from the oil of turpentine : and, tho' 
 the latter will not in the leaft counteract the 
 intention of the former, yet it perverts the due 
 proportion of the dofe ; and eludes, in that re- 
 Ipeft, the defign of the prefcriber. 
 
 The oil, diftilled from coal, treated, for that 
 end, in the fame manner as amber, has been 
 fubftituted for the oil of amber 3 and is faid to 
 be the fame : but at prefent the fmall con- 
 fumption of the oil of amber, the plenty of 
 it with thofe, who prepare the fait, and the in- 
 creafe of it in the hands of others, by the ad- 
 dition of oil of turpentine, have taken away 
 the temptation, which Wilfon, who introduced 
 this fubftitution, might have, in his time, for 
 pradtifing it. 
 
 Method 
 
Chemical Preparations. 207 
 
 Method of making yelhw arfenic. 
 
 Take, of arfenic powdered, one pound, 
 of flowers of fulphur, half a pound : mix 
 them well, and fublime them, in a cucurbit, 
 of an oval form, in the fand-pot defigned 
 for the fublimation of calomel ; keeping up 
 the fire as high as may be, without forcing 
 out the fumes from the mouth of the cucur- 
 bit : when the whole is fublimed, which may- 
 be known by the abatement of the heat in 
 the upper part of the cucurbit, the fire mufl: 
 be difcontinued -, and the cucurbit broken, 
 when cold, to take out the cake of yellow 
 arfenic. 
 
 Note. 
 
 This fubftance is not ufed in medicine; nor 
 much for any purpofe, but in the dying the 
 colours called Saxon blue and green : for 
 which, at one time, it was greatly wanted ; 
 and fetched from abroad, at a very confiaera- 
 ble expence : to avoid which inconvenience to 
 the public for the future, I have inferted this 
 procefs, by which it may be made, with very 
 little expence and trouble, here. 
 
 SECTION 
 
zoS Chemical Preparations* 
 
 SECTION IV. 
 
 Of the preparation of thofe medicines 
 where metalline fubjlances make the 
 whole y or principal part ofthefubjeEl. 
 
 Purification of mercury. 
 
 Diftill the quickfilver, in a retort ; and 
 then wafh it well with water and fait, or 
 vinegar. 
 
 Note. 
 
 This is the direction of the college of Lon- 
 don. But the diftillation of the quickfilver in 
 a retort is hardly practicable : for the great heat, 
 *nd denfity, of the fumes, when collected a- 
 gainft the fides of the neck of the retort, heat 
 it fo unequally, that it is fcarcely poilible to 
 prevent its being cracked, and falling to pieces, 
 during the operation : and there is, indeed, 
 another reafon againft the ufe of a retort ; 
 which is, that a fand heat is fcarcely fufficient 
 to raife the fumes of the mercury into the 
 depending part of the neck of them ; and the 
 ufing them coated, and in the naked fire, is 
 attended both with much trouble and hazard. 
 If, however, a retort be ufed, it fhould be of a 
 low round form -, and placed fo in the furnace, 
 
 that 
 
Chemical Preparations. 209 
 
 that the neck, which fhould alfo be very fhort, 
 may be as depending as poilible, that the quick- 
 filvermay not lodge ink; but fall, as it colleds 
 in droos, inftantly into the receiver ; which 
 fhould be half filled with water, before it be 
 put to the retort. The method, below given * 
 faves all this trouble ; avoids the hazard ; and 
 may be performed any where, with a com- 
 mon fire, without employing a furnace. 
 
 The wafhing the quicklilver in fait and wa- 
 ter, or vinegar, after the diftillation, feems 
 intirely needlefs and ineffectual ; for the mer- 
 cury will certainly be freed from any adul- 
 terate mixture, by the diftillation : and, if it 
 were not, the wafhing in brine, or vinegar, 
 could not avail, in the leaft, to that end. 
 
 More expedite method of purifying quickfiher y 
 by means of the alembic dcfcribed p. 43. 
 
 Take any quantity of quickfilver ; and 
 put it into the iron alembic, directed to be 
 made for this purpofe : the ftopper being 
 fkrewed in to the hole at the top, place it 
 on a culinary fire, raifing the coals round 
 it : let an earthen pot, filled with water, 
 be fo placed, that the bended end of the 
 iron tube of the alembic may lie immerfed, 
 two or three inches within the water ; and 
 
 P the 
 
210 Chemical Preparations* 
 the fumes of the quickfilver will be then 
 condenfed in the tube ; and run down into 
 the water : when the whole is diftilled, which 
 may be eafily perceived by the quickfilver's 
 ceafmg to jdrop into the veflel of water, 
 the ftopper may be taken out ; and the 
 alembic replenifhed at pleafure, without 
 taking it from the fire. 
 
 Note. 
 
 By this method, very great quantities of 
 quickfilver may be diftilled, without the leafi: 
 trouble or expence : and this operation ought, 
 therefore, to be always previoufly pradtifed on 
 the quickfilver, of which the ethiops mineral, al- 
 calizate mercury, and precipitates of every kind, 
 are prepared ; or in cafe of any other prepara- 
 tion, where there is no fubfequentfublimation, 
 in order to free the quickfilver from thofe al- 
 moft conftant adulterations, that are made on 
 it; and which may be diftinguifhed, by the me* 
 thod below given, where we treat of the fo- 
 phiftication of firnples $ and the means of 
 detecting them. 
 
 Corrofive mercury fublimate. 
 
 Take, of purified quickfilver, forty ounces ; 
 of fea fait, thirty three ounces, of nitre, 
 
 twenty 
 
Chemical Preparations. 21 i 
 twenty eight ounces, and of green vitriol 
 calcined, fixty fix ounces : let the quick- 
 filver be mixed, in a veflel of ftone, or 
 wood, with one ounce* or more, of mer- 
 cury fubiimate already made, and brokefi 
 into fmall grains : then let it be ground 
 with the nitre, and afterwards with the fea 
 fait, till there be no longer any appearance 
 of quickfilver : when add the calcined vi* 
 triol 5 in the commixture of which, with the 
 others, the operation fhould not be too 
 much prolonged ; left the quickfilver re- 
 vivify, or reaflume its fluid ftate : laflly, 
 fublime the mixture in a glafs mattrefs ; to 
 which, at difcretion, a proper head mull be 
 fitted, to fave the fpirit ; of which a fmall 
 quantity will rife. 
 
 Note. 
 
 This is the procefs of the college of Lon- 
 don ; and one of the beft for making fubiimate^ 
 by the means of green vitriol and nitre. 
 
 The greateft difficulty, in this procefs, is thef 
 fixing the quickfilver, in order to its commix- 
 ture with the other ingredients ; which is very 
 troublefome. An ounce of fubiimate, already 
 made, and broken into fmall grains, is ordered 
 to be ufed for this purpofe ; but it is better to 
 
 P 2 take 
 
212 Chemical Preparations. 
 
 take a greater quantity, to reduce it to pow- 
 der, and to moiften it with fpirit of fait ; by 
 which means, this tedious operation may be 
 much fhortned. 
 
 The mattrafs, in which this fublimation is to 
 be made, fhould not be quite half filled with 
 the ingredients : it fhould be placed in the pot, 
 in fuch manner, that the fand may rife round 
 it a little higher than the part of it occupied by 
 the contents. 
 
 But, though a mattrafs be here directed, 
 large cucurbits, or bodies, of an oval form, 
 are almoft univerfally ufed ; and with great 
 reafon : for, as only a fmall quantity of fubli- 
 mate is produced from this great mafs of in- 
 gredients, if the veffel, in which the fublima- 
 tion is made, be not capable of "holding a con- 
 fiderable quantity of materials, not only the 
 time, and fire, employed, in obtaining fo 
 minute a proportion, but the fmall fize of 
 the cake of the fublimate, render it very dis- 
 advantageous. The large fand-pot, and not 
 that intended for the fublimation of calomel, 
 is, therefore, much better accommodated to 
 this purpoie : and the cucurbit fhould be cho- 
 ien^ as large as the furnace will admit ; (for 
 glafies of this form may be blown of almoft 
 any magnitude ; and it may be filled, to the 
 height of three quarters, with the materials : 
 the find being brought round it, fomething 
 higher than the contents. 
 
 But the ufe of the crude vitriol, in making 
 fublimate, is wholly unnecellary : for it has no 
 
 effeft 
 
Chemical Preparations. 213 
 
 effedt in the procefs, but in difcharging the 
 lpirit of nitre from the fait ; which may e- 
 qually well be previoufly done, as the Edin- 
 burg procefs directs ; where a folution of the 
 mercury is ordered to be made in fpirit of ni- 
 tre; and the fait produced brought to a dry ftate, 
 and mixt with an equal quantity of fea fait, 
 and then fublimed : by which method, the 
 volume is greatly reduced > and the fublimate 
 much lefs liable to be difcoloured, or otherwife 
 injured, in the operation. 
 
 There is, neverthelefs, a much lefs expen- 
 five and troublefome way, even than this, by 
 which the expence of the nitre, and the pains 
 and coft of the operation, for extracting the 
 lpirit from it, may be wholly faved. The prac- 
 tice of it has been hitherto confined, I believe, 
 to one place ; by perfons, who at prefent are 
 attempting to monopolize this article, with 
 fome others : but, for the benefit of the pub- 
 lic, I will here lay it open, in the moft explicit 
 manner, I can, with the attendant advantages ; 
 and particularly recommend it to thofe, who 
 may ere£t works for the preparing oil of vitriol 
 from fulphur. 
 
 ffle mofi cheap and expedite manner of making 
 the corrofive mercury fublimate, by the life 
 of oil of vitriol, alone \ with the quickflver. 
 
 Take, of quickfilver, twenty pounds; of 
 
 oil of vitriol, nine pounds : having put them 
 
 P 3 toge- 
 
214 Chemical Preparations. 
 together, in a retorts and placed it in 3 
 fand-pot, diftill till the fumes begin to ap- 
 pear white : take the mafs which will be 
 found in the retort, and mix, with it, 
 eighteen pounds of common fait ; rubbing 
 them together, till they appear as one body ; 
 put this mafs into a cucurbit, of which it 
 will occupy fomething lefs than three quar- 
 ters of the cavity ; and place it in a fand- 
 pot, to fublime. When the fublimation is 
 finifhed, take away all parts of the cake of 
 fublimate, which are not tranfparent, an4 
 white. 
 
 Note. 
 
 By this method, the whole procefs is greatly 
 contracted, both with regard to time, and the 
 volume which the matter occupies in the fub- 
 liming veffel -> and the fublimate is much lefs 
 liable to mifcarry, in the preparation, than when 
 the crude vitriol and nitre are ufed : but if any 
 difcoloured parts fhall happen to be found, they 
 may be employed in making the white preci- 
 pitate, as dire&ed in the procefs of the college 
 of London ; for which end, it will equally 
 well ferve, with that which is of the pureft 
 whitenefs. 
 
 There is another fource of profit opened, by 
 this method of making fublimate : for tho 
 
 whole 
 
Chemical Preparations. 215 
 
 whole of the recrement, or caput mortuum, 
 left behind in the retort after the fublimation, 
 is the true fal mirabile, or Glauber's fait; and 
 being taken out, and treated in the fame man- 
 ner, as the cake formed in the retort, when 
 the regular procefs for fal mirabile is per- 
 formed, (that is to fay, diflblved and chryftal- 
 lized,) it will, in all refpefts, be the fame as if 
 the oil of vitriol and fea fait had been put alone 
 into the retort. It may be proper, however, 
 to put two or three ounces of pearl afhes into 
 the folution of this fait, before it be filtered 
 previoufly to the chryitallizing ; and if the 
 commixture of this alkaline fait produce a 
 white turbidnefs, it will be proper to add an- 
 other ounce of the pearl afhes, and to repeat 
 this addition, fo long as it produces any cloudi- 
 nefs, or till the fediment, which it caufes, be- 
 come of an orange colour, or brown. The 
 reafon of this addition, is to analyze any fub- 
 limate, which may remain unfublimed ; or 
 may have fallen from the cake, or the fides 
 of the cucurbit, in the taking it out, or break- 
 ing the glafs : and which, by means of the 
 alkaline fait, will have its elements difunited ; 
 the mercury becoming a folid precipitate, and 
 the fpirit of fait, the other conftituent, com- 
 bining with the alkaline fait, and forming that 
 fait, which the college of London have ho- 
 noured, with a fpecial procefs, under the name 
 of the fal marinus regeneratus. If the de- 
 ftroying the prevalence of the acid, in the fo- 
 lution, by this commixture of alkaline fait 
 
 P 4 with 
 
2i6 Chemical Preparations. 
 
 with it, fhould render the chryftallization 
 weak, and tardy, an ounce or two of oil of 
 vitriol, dropped.into the folution, will take a- 
 way any fuch reluctance ; and make the fait 
 ihoot as freely, as if no alkaline fait had been 
 ufed. There will be gained, by this means, 
 near a pound of Glauber's fait, for every pound 
 of the fublimate j which v/ill defray the ex- 
 pence of the oil of vitriol, and glaifes for the 
 luhlimation ; and, together with the great fa- 
 cility, this method affords for the preparation 
 of fublimate, renders it an article, which may 
 be very advantageous to thofe, who prepare 
 jnedicines for wholefale demands : efpecially, 
 if they undertake, likewife, to extraft the oil 
 of vitriol from fulphur, by the new method : 
 which, at prefent, would be found attended 
 with great convenience, and profit, to all, who 
 have large elaboratories ; or a demand, either for 
 ufe, or fale, of any confiderable quantity of that 
 commodity. 
 
 It has been common to praftife themoft 
 villainous fophiftication, with refpeft to fubli- 
 mate, which has ever hitherto difgraced the 
 morals of mankind, by adulterating it with a 
 fubftance of the moft poifonous nature. I 
 fhall be iilent here, as to any further explana- 
 tion, either of what this fubftance is, or how it 
 is to be employed for this wicked purpofe; 3 as 
 I would not, on any account, be the cauie of 
 propagating fuch deteilable arts : but, inftead 
 of furnifhing thofe, who are ignorant of it, 
 with the method of pradtifing this curfed fo- 
 2 phiftication, 
 
Chemical Preparations, 217 
 
 phiftication, I will furnifh a method, by which 
 any perfon may ealily difcover, where it has 
 been made ; and have it in their power to re- 
 ject fuch parcels of the fublimate, as they find 
 to be of this adulterate kind. This method is 
 as follows. 
 
 Method of deteBing the adulteration of corro* 
 fve fublimate. 
 
 Take, a fmall quantity of the fublimate 
 fufpe&ed ; and diflblve it in boiling water : 
 take, alfo, about double the quantity of 
 any fixt alkaline fait, and make a clear fo- 
 lution of it : mix them together ; and a 
 precipitation will follow 3 from which, if it 
 be immediately of a black colour, it may be 
 concluded, that the fublimate was adul- 
 terated in the manner fufpe&ed -, but, if it 
 appear of an orange colour, it may be 
 deemed free from any fuch depravity. 
 
 N. B. The obfervation on the colour, as 
 a criterion of this difference, muft be made 
 foon after the commixture : for the orange 
 colour will fometimes change to black, on 
 flanding a confiderable time,, even in the 
 cafe of the beft fublimate j if the fluid, in 
 
 which 
 
218 Chemical Preparations. 
 which the precipitation is made, abound 
 with alkaline fait 
 
 Preparation of calomel. 
 
 Take, of corrofive mercury fublimate, 
 one pound ; of purified quickfilver, nine 
 ounces : the mercury fublimate being firft 
 powdered, put it, together with the quick- 
 filver, into a glafs mattrafs ; and digeft, 
 with a flow heat, in fand, the glafs being 
 frequently fhaken, till they incorporate : 
 then augment the heat, and fublime them : 
 powder the fublimed matter, having freed 
 it from the acrid upper part, and the glo- 
 bules of quickfilver, if any appear; and 
 then fublime it again : the fublimation muft 
 be fix times repeated. 
 
 Note. 
 
 The repetition of the fublimation (even 
 times is rarely pradtifed ; three, or four, being 
 the utmoft, which are afforded in the elabora- 
 tories for fupplying coniiderable quantities of 
 medicines ; nor can any reafon be given, why 
 that number, properly managed, may not re- 
 duce the calomel to the fame ffcate, as feven 
 
 hundred. 
 
Chemical Preparations. 219 
 
 hundred. It is obvious, that all, which the 
 heat can effedt, is the equal mixture of the acid 
 and mercury, which conftitute the calomel; 
 and the driving out any redundant part of the 
 firft : and, certainly, this may be more effec- 
 tually done by other means, than the tedious 
 repetition of this troublefome and expenfive 
 operation, 
 
 The purification of the mercury by fubli- 
 mation is, alfo, needlefs ; for nothing, with 
 which mercury can be adulterated, will rife on 
 the fublimatibn. It is fufficient, therefore, to 
 prove it, by {training a fmall quantity through 
 leather ; and, if no pafte like amalgama be 
 found remaining in the leather, but, that the 
 mercury fuifer itfelf to be wholly prefied 
 through, which proves that the proportion of 
 the fpphifticated matter, if there be any, mufl 
 be only fmall, there can be no inconvenience 
 from ufing the mercury, though not pure, 
 further than a proportionable defedt of the pro- 
 duce of fublimate : but even fhould a greater 
 adulteration be found, if fome of the mercury 
 be put in a crucible into a common fire, and 
 continue there till it be diflipated by the heat, 
 and the caput mortuum weighed, in order to 
 make a proper allowance in the compofition of 
 the ingredients, for the defecft in the mercury 
 arifing from the fophiftication, fuch mercury 
 may be equally well ufed, as that which is ab^ 
 fplutely pure. 
 
 There is a flaky laminated appearance in ca- 
 Jpmel, the dealers in medicines value in k, 
 
 which 
 
220 Chemical Preparations. 
 
 which is owing to the greater proportion of 
 mercury ; and to the brifknefs of the heat in 
 the f .ibiiination. I fuppofe the reafon for pre- 
 ferring this appearance, is from the experience 
 of its moftly attending that calomel, which 
 they know has unde/gone, a great number of 
 fublimations : but as it is eafily practicable, to 
 diminifh the quantity of the acid fpirit in ca- 
 lomel, with a much lefs number of fublima- 
 tions, this appearance may, confequently, be 
 produced, as well as all the other qualities which 
 are to be defired in this medicine. The fol- 
 lowing method, in particular, will produce ca- 
 lomel by three fublimations, indiftinguifhabley 
 in all its properties, from the beft that can be 
 made by any repeated number whatever. 
 
 More expedite method of producing perfeSl ca- 
 . kmelj where the fublimation is only three 
 times repeated. 
 
 Take, of corrofive mercury fublimate, 
 twelve pounds •> of quickfilver, if pure, nine 
 pounds ; or, if otherwife, fuch a propor- 
 tion as may allow for the adulteration, 
 which muft be previoufly afcertained : the 
 fublimate, being powdered, divide it into 
 three equ#l parts j and put it, with a pro- 
 portionable divifion of the mercury, into 
 
 three 
 
Chemical Preparations. 221 
 
 three mattraffes ; and place them in a gentle 
 fand heat, fhaking the mixture frequently 5 
 where they mufl continue, till they appear 
 to be intirely incorporated : then put the 
 whole together into one mattrafs, of which 
 they v will fill about one half \ and place it 
 in the fand-pot, defcribed p. 25 for this 
 purpofe ; the mattrafs being immerfed in 
 the fand fomething more than one half: 
 let the matter be then fublimed with a mo- 
 derate heat -, and, the fublimation being 
 finiflied, break the glafs ; and, having taken 
 out the fublimed cake, feparate carefully all 
 the yellow parts, if any be found j and le- 
 vigate the other, but without moiflure, mix- 
 ing with it two pounds of frefh quickfilver, 
 rubbed to powder, firft with half an ounce of 
 fublimate : repeat then the fublimation an$lle- 
 vigation as before, adding, at this fecond levi- 
 gation, only a pound of the quickfilver treated 
 as before : fublime then a third time \ and le- 
 vigate, but without any further addition of 
 quickfilver ; and afterwards give the fourth 
 and laft fublimation, with the ftrongeft heat 
 that can be ufed without blowing the fumes 
 of the mercury out of the neck of the mat- 
 trafs ; 
 
222 Chemical Preparations. 
 trafs. Take out then any difcoloured part j 
 as, alfo, the upper part of the cake in the 
 neck of the retort ; if it appear any way to 
 differ in its texture from the reft. 
 
 Note. 
 
 The calomel, thus prepared, will be as per- 
 fectly free from any corrolive qualities, as any 
 number of fublimations whatever can render 
 it : the colour will be perfectly white ; and it 
 will, alfo, have that flakey laminated appear- 
 ance, which good calomel is fuppofed to require. 
 
 The fourth fublimation may be fpared, by 
 thofe, who prepare this medicine for fale, if the 
 other parts of the procefs be duly executed : but, 
 in that cafe, the third muft be performed with 
 the ftrong heat directed otherwife for the fourth* 
 
 The yellow, or other rejected parts of the 
 calomel, may be employed along with the 
 crude mercury : in making fublimate with oil 
 of vitriol. 
 
 It has been too ufual to adulterate calomel, 
 as well as fublimate, with the poifonous ingre- 
 dient before mentioned j and I have feen a 
 recipe, (given by a German empyric, who has 
 for fome few years infefted this country, and 
 pretends to knowledge in almoft every branch 
 of chemiftry,) which directed this ingredient 
 to be ufed in a very large proportion, which, if 
 it happened to be joined to Venetian fublimate, 
 that ihould contain, likewife, a large proportion 
 1 of 
 
Chemical Preparations. 223 
 
 of the fame fubftance, as is frequently the cafe, 
 apoifon, that fcarcely the ftrongeft conftitution 
 could refift,muft have neceffarily been produced. 
 The preparers of medicines for the Weft-India 
 trade, have, likewife, adopted this execrable 
 practice ; and, on inquiry, for what purpofe the 
 matter of this adulteration was preparing, in a 
 large quantity, the ufe of it, for this end, has 
 been freely avowed; with the apology, that 
 the calomel would be adminiftered only to 
 negroes. In order, therefore, to prevent fuch 
 dangerous preparations being impofed on thofe, 
 who are duly careful, and that they may not 
 be liable to give, perhaps, a fcruple of fuch 
 calomel, as I have feen kill a dog in the quan- 
 tity of three grains only, though fetched from 
 the fhop of a very great dealer in medicines, I 
 will give an infallible method of detecting this 
 pernicious fraud; as the means before dire&ed, 
 to be ufed for this purpofe, with refped: to fubli- 
 mate, are not practicable in the cafe of calomel, 
 as it is not capable of being diffolved in water. 
 
 Method of detecting the adulteration of calomel. 
 
 Take a frnall quantity of the fufpecled 
 calomel : powder it with about a third of its 
 weight of flowers of fulphur : put the mix- 
 ture into a crucible, over which a leffer is to 
 be inverted as a cover : place the crucible in a 
 common fire, that it may have a heat fufii- 
 
 cient 
 
224 Chemical Preparations. 
 cient to raife the fulphur in fumes. If the 
 calomel be adulterated, as fufpe6led, a very 
 offenfive alliaceous fmell, like that of orpi- 
 ment, will be perceived : but if none fuch be 
 found to be produced, it may be taken for 
 granted, that it is free from the mixture of 
 the pernicious ingredient, ufed for its fo- 
 phiftication. This adulteration may be, 
 alfo, perceived, but with lefs certainty, by 
 dipping a piece of the calomel, unground, 
 into a folution of fixt alkaline falts 3 which, 
 if it be fophifticate, will turn it black ; but, 
 if not, to an orange colour. 
 
 Note. 
 
 The frequent complaints of tormina, and 
 fometimes even bloody ftools, which happen on 
 the taking calomel, are probably more owing- to 
 this adulteration, either made, originally, in the 
 preparation of the fublimate, or, afterwards, in 
 that of the calomel, than to any other caufe. It 
 is advifable, therefore, always, when fuch con- 
 fequences happen, to examine the calomel , 
 and prove it, by this means : for, where the 
 fophiftication happens to be in the fublimate, 
 the moft careful and confcientious preparer of 
 the calomel may be deceived : and it is, there- 
 fore, very proper, alfo, that all, who do not pre- 
 pare the fublimate themfelves, which is the cafe 
 
 of 
 
Chemical Preparations, 225 
 
 of very few, fhould examine it by the means 
 above given : as there is no excufe for placing 
 a confidence in the preparations of foreigners ; 
 which are imported here in fuch a manner, 
 that it is impoffible to trace back any fophifti- 
 cate parcel, to the hands of thofe who prac- 
 tifed the fraud : and the invention of this mon- 
 ftrous impofition is of fo old a date, that me- 
 moirs of it may be found of a hundred and 
 fifty years {landing : from whence we may 
 conclude it, to be very well known at prefent, 
 in all places, where the manufacture of fubli- 
 mate has been long carried on. 
 
 White precipitate of mercury. 
 
 Take, of fal ammoniacum, and corrofive 
 fublimate, each an equal weight : diflblve 
 them together in water ; and, having fil- 
 tered them through paper, make a precipi- 
 tation, with a folution of any fixt alkaline 
 fait : wafh thte precipitated powder till it 
 be perfectly fweet. 
 
 Note. 
 
 The ufe of the fal ammoniacum in this 
 procefs, which is that of the college of Lon- 
 don, is, we are told, to facilitate the folution 
 of the fublimate in the water ; to which it is 
 otherwife very reluctant : but it does not ap- 
 
 Qw P ear 
 
226 Chemical Preparations. 
 pear to anfwer, in the leaft, that end, when 
 carefully tried : nor is there any difficulty in 
 diflblving the fublimate, previoufly powdered, 
 in a fufficient quantity of boiling water : for, 
 though a large proportion be required, yet that 
 does not produce any inconvenience, in this 
 operation, the removal of which might bal- 
 lance the ex^ence of the fal ammoniacum. 
 
 The filtering the folution is likewife wholly 
 unneceflary, if the fublimate and water be 
 clean : nor is it even requiilte, when fal am- 
 moniacum is ufed ; if foul pieces of the fait 
 be not ufed without fcraping. 
 
 The folution of the alkaline fait muft be 
 added, by degrees, to that of the fublimate ; 
 and with great caution, when near the due 
 quantity has been added : for, if a fufficient 
 quantity be not ufed, a part of the fublimate 
 will remain in the folution unprecipitated ; 
 and, confequently, be wafted ; and, if more 
 than the proper quantity be ufed, the colour 
 of the precipitate will be fpoilt; as the fmallefl 
 excefs, in the proportion of the alkaline falts 
 to the fublimate, turns it yellow ; and a greater 
 quantity orange. It is proper, therefore, to re- 
 ferve fome part of the folution of the fublimate; 
 which being added, may bring back the colour 
 of the precipitate, if it be hurt by an error in 
 this point ; and by thus adding a little of each, 
 as the effect of the commixture may indicate, 
 the due ballance of them may be obtained with 
 great exadtnefs. 
 
 But, 
 
Chemical P&eMrations. 22f 
 
 But, notwithstanding the college of London 
 have directed this procefs to be followed, in 
 the making the white precipitate, the produce 
 of which the college of Edinburg have diftin- 
 guilhed very properly by the name of the fweet 
 precipitate, there are fume, who do not prepare 
 it by this means ; but perfue the former method, 
 of preparing it with aqua fortis from the crude 
 quickfilver ; that being, all things confidered, 
 the cheapeft method 2 as a pound of quick- 
 filver, treated this way, will afford a fourth, or 
 fifth more than its own weight ; as the acid of 
 the fpirit of nitre, and of the fea fait, employed 
 in its preparation, remain combined with it $ 
 whereas* on the contrary, a pound of fubli- 
 mate will not afford three fourths of its own 
 weight in precipitate ; as it is deprived of its 
 acid, by the ufe of the alkaline fait. There is, 
 alfo, another reafon, why this latter preparation 
 fhould be followed by thofe, who make white 
 precipitate for fale 5 which is, that as the prin^ 
 cipal demand for it is made by the farriers, who 
 ufe it as a kind of efcarotic, if the other method 
 be adopted, the produce will be rendered wholly 
 unfit for their purpofe : for the precipitate is fo 
 much deprived of its acid, in which alone the 
 cauftic quality of it confifts, that they may a9 
 well ufe minium, powdered tin, or any other 
 metallic pulverifed body. It was, therefore, very 
 judicious in the Edinburg college, not to rejed: 
 the old manner of preparation, as the London 
 college have fince done; but to retain that, and 
 take in, likewife, the new one ; diftinguiihing 
 
 Qj2 them 
 
228 Chemical Preparations. 
 
 them by the names of white, and fweet preci- 
 pitate ; as their qualities are eflentially different ; 
 and thefe names properly fignificant of that dif- 
 ference : the white meaning the old kind, which 
 is in fome degree corrofive, and, therefore, pro- 
 per to be ufed externally, and for the purpofes 
 of the farriers ; the fweet meaning, that it is 
 devoid of any faline nature, or cauftic quality, 
 and, confequently, fit for internal ufe. The 
 old procefs ought, therefore, certainly, to have 
 a place, as well as the new ; and may be beft 
 performed in this manner. 
 
 Mojl expedite method of preparing white pre- 
 cipitate of mercury > by means of folution in 
 fpirit of nitre. 
 
 Take, of quickfilver, and pure fpirit of 
 nitre, each equal quantities : put them in- 
 to a mattrafs, with a long neck ; and place 
 it in a fand heat of digeftion : where let it 
 ftand, often fhaking the ingredients toge- 
 ther, till the mercury appear to be perfe£tly 
 diifolved, or rather converted into a white 
 fait; for this proportion of fluid will not 
 be fufficient to keep diffolved, the fait pro- 
 duced ; at leaft, when not of a boiling heat : 
 let the mattrafs, therefore, be removed to a 
 degree of heat fufficient to make it boil, a 
 
 fmaller 
 
Chemical Preparations* 229 
 
 fmaller mattrafs being put with its neck 
 inverted, into that containing the folution ; 
 and there continued till the fait appear to be 
 wholly diffolved -, which, if it cannot be 
 performed without a greater proportion of 
 fluid, mull be effected by the addition of 
 a fmall quantity of hot water 3 that muft 
 be added, by degrees, till no folid mafs ap- 
 pear to be left in the mattrafs. A ftrong 
 brine muft then be made of fea fait, by 
 pouring hot water on common fait, in 
 the proportion of five pints to two pounds ; 
 and when the folution of the fea fait is cold, 
 the folution of the mercury while, yet hot, 
 muft be poured into it ; the proportion of 
 brine ufed, being two pints to every pound 
 of quickfilver contained in the folution : 
 the quickfilver will then be foon precipi- 
 tated, and fubfide to the bottom \ leaving 
 the fluid clear above it ; which as foon as 
 it appears fo, muft be poured off -, and an 
 equal quantity of frefti water, or more, if 
 the veffel will contain it, added to it : this 
 fecond quantity muft, likewife, be poured 
 off, from the precipitate, as before ; not 
 Q 3 fuffering 
 
gjo Chemical Preparations, 
 fuffering it to ftand longer, than till it be- 
 come clear by the fubfiding of the precipi- 
 tate. The remaining fluid, and fediment, 
 muft then be put into the cullender filters, 
 with paper covered with a linnen cloth ; an4 
 when the fluid is drained off, and the pre-* 
 cipitate left of a due confidence, it muft 
 be laid out, on a proper board, to dry, in 
 fmall lumps, in the fhade, 
 
 Note. 
 
 The defign of the precaution of making fa-* 
 turated folutions, both of the mercurial and 
 fea fait, is, to prevent the lofs, which, other- 
 wife, happens from part of the quickfilver re- 
 maining diflblved ; as the precipitated matter is, 
 in fad:, itfelf, in a faline ftate, and quits the 
 fluid, rather from the defecft of a fufficient 
 quantity to keep it diflblved, than from its be- 
 ing rendered of an indiflcluble nature : and, for 
 the fame reafon, the water muft be fparingly 
 ufed in waffling off the falts; and not fuffered to 
 ftand long upon the precipitate. The great care- 
 fulnefs, in this point of wafhing, which the 
 Edinburg college fliow, when they direft frefh 
 quantities of water to be added, till it come off 
 without any acrimony, is exercifed without any 
 adequate obje<5t : for as the fluid, after the pre- 
 cipitation, is made, contains nothing but nitre 
 and fea fait, befides the precipitate, there can 
 
 he 
 
Chemical Preparations. 231 
 
 be no acrimony in queftion, but that, which 
 is in all fca fait, and nitre, in their proper neu- 
 tral ftate; and, therefore, none which can give 
 any injurious qualities to the precipitate, even 
 when internally taken. 
 
 The white precipitate is very rarely to be 
 found without great adulteration 5 as few per- 
 fons take the trouble of preparing it, but thofe, 
 who make chemical medicines in great quan- 
 tities. The moft ufual ingredients, mixed 
 with it, are white lead and ftarch : the white 
 lead being ufed, for the fake of its weight, 
 and the ftarch for its whitenefs : and fuch kind 
 of practices have become fo general, with re- 
 fpe<ft to this fubjeft, that I have fcen an emi- 
 nent vender of drugs, and chemical prepara- 
 tions, rejefl: a parcel of genuine white preci- 
 pitate, on account of its being greatly heavier, 
 than what he had been accuftomed to be fup- 
 plied with; though the weight is an unquesti- 
 onable mark of its being really unadulterated. 
 The certain means, however, of detecting any 
 fuch fraud, pradtifed, in the cafe of the white 
 precipitate, are, however, veryeafy; of which 
 this method is one. 
 
 Method of detecting adulterations of the white 
 precipitate of mercury* 
 
 Take any quantity fufpe6led ; and put it 
 in a crucible, with a third of its weight of 
 
 0^4 an y 
 
232 Chemical Preparations. 
 any fixt alkaline fait: place the crucible, in 
 fire, where the matter in it may be heated 
 red-hot : let it continue there, while any 
 fumes arife : then take it out 5 and examine 
 if there be any appearance of melted metal 
 at the bottom ; if not, put the refiduum, or 
 caput mortuum, left in it, into boiling wa- 
 ter ; obferving whether the water diffolve the 
 whole of it or not. 
 
 If there be any appearance of melted 
 metal remaining in the crucible, or, if the 
 other matter found in it, do not diffolve in 
 the boiling water, it may be concluded, 
 that the precipitate was adulterated, either 
 with fome metal, or earth, in the fame pro- 
 portion : for the mercury being feparated, 
 by the a6lion of the alkaline fait, from the 
 acid, would of courfe be diffipated in fumes ; 
 and the acid would combine with the alka- 
 line fait, and from the vitriolated tartar ; fo 
 that, if the precipitate were genuine, there 
 could be no metal, nor earthy body re- 
 maining : and whatever of fuch kind fhould 
 appear to be found in the crucible, with the 
 caput mortuum, which ought to be wholly 
 
 of 
 
Chemical Preparations. 233 
 
 of a falinc nature, muft neceflarily have 
 been mixt with the precipitate in order to 
 its adulteration. 
 
 The addition of ftareh, to the white 
 precipitate, may be perceived by the light- 
 nefs of the mafs ; and may be demonftrated, 
 by putting a fmall quantity of what is fu- 
 fpe6led, on a red-hot poker, or into a cru- 
 cible, with another fmaller one inverted into 
 it, and heated in the fire $ which will re- 
 duce the ftareh to a coal, if there be any ; 
 and render it palpably difcernible. 
 
 Red precipitate of mercury. 
 
 Take, of aqua fortis, fixteen ounces, of 
 fea fait, one dram : diftill off the fpirit fo 
 long as any will rife. 
 
 In the compound aqua fortis, thus pro- 
 duced, diffolve an equal weight of purified 
 quickfilver ; and, being evaporated, calcine 
 them in a fand heat, till the dried mafs has 
 acquired a red colour. 
 
 Note. 
 
 This is according to the procefs of the col- 
 lege of London $ but, on experiment, the me- 
 thod 
 
234 Chemical Preparations, 
 thod will be found defective in feveral refpe&s; 
 and whoever, therefore, would manage this 
 preparation advantageoufly, muft perfue better 
 means. 
 
 In the firft place, aqua fortis, compounded 
 with a fmall quantity of fpirit of fait, is ordered 
 inftead of pure fpirit of nitre. The aqua for- 
 tis itfclf, which muft be underftcod to be that 
 made according to the procefs of the college, 
 is a compound, alfo, of oil of vitriol and fpirit 
 of nitre : for, from the proportion of vitriol 
 ufed in the preparation, if the diftillation be 
 made with a ftrong fire, a confiderable quantity 
 of the oil of vitriol will neceflarily be raifed with 
 the fpirit of nitre ; fo that the menftrum, em- 
 ployed for diffolving the quickfilver, is a mix- 
 ture of the three acid fpirits of vitriol, nitre, 
 and fea fa-It > which have no joint operation on 
 the quickfilver, but each combining with its 
 proper portion, will produce the refpe&ive fait 
 fuch combination forms. It is faid, however, 
 that the addition of the fea fait is neceftary to 
 form that fparkling appearance, which is e- 
 fteemed in the red precipitate : but this can 
 be no way owing to the effedt that fuch fait 
 may have on the quickfilver itfelf ; for, tho' 
 the oil of vitriol in the aqua fortis, or even 
 the fpirit of nitre, if there were no oil of vi- 
 triol, would let loofe the fpirit of the fea fait, 
 which, if the quantity of quickfilver added 
 were as much as the whole of the acid could 
 difiblve, would form a proportionable quantity 
 of fublimate, yet the quantity of oil of vitriol, 
 
 and 
 
Chemical Preparations. 235 
 
 and fpirit of nitre, being greater than fufficient 
 to diffolve the whole quantity of quickfilver, 
 the fpirit of the fea fait would be prevented, by 
 the fuperior attraction of the others, from com- 
 bining with any part of the quickfilver ; and 
 would, confequently, be raifed in vapour, and 
 diflipated in the evaporation of the folution, 
 previous to the calcination of the precipitate : 
 and were, really, any quantity of fublimate 
 formed, that would likewife be raifed in the 
 calcination, and fly off in fumes, without any 
 effedt on the remaining matter. If the fea 
 fait were, indeed, added to the aqua fortis, and 
 no fubfequent diftillation of the acid fpirit 
 made, the fmall quantity of fal mirabile, pro- 
 duced by the combination of the vitriolic acid 
 with the alkaline bafis of the fea fait, might 
 add to the fparkling appearance of the red pre- 
 cipitate ; as the fait itfelf powdered in the flate it 
 would be here found, has a fparkling appear- 
 ance ; but this is wholly put out of queftion, 
 by the exprefs direction, given in this procefs, 
 for diftilling the aqua fortis, after the addition 
 of the fea fait, though, as I prefume, from fome 
 miftake. The only effe&ual difference, there- 
 fore, betwixt the ufe of the pure fpirit of nitre, 
 and this compound aqua fortis, muff appear to 
 be, that a part of the mercurial fait, formed in 
 order to produce the red precipitate by the fub- 
 fequent calcination, muff be compounded from 
 the vitriolic acid in the aqua fortis, and, confe- 
 quently, be the fame, as that from whence the 
 turpeth mineral is, by a fimilar calcination, pro^ 
 I duped \ 
 
236 Chemical Preparations. 
 
 duced 5 which being only a white mafs, unlefs 
 converted into a yellow one by the addition of 
 water, muft weaken the red colour of the preci- 
 pitate 5 and change greatly its medicinal qua- 
 lities ; and that, not in any certain proportion, 
 but as the vitriolic acid fhall happen to abound 
 more or lefs in the aqua fortis, according to the 
 degree of fire ufed in the diftillation of it, or 
 other attendant circumftances. It is, there- 
 fore, much better, with refpedt to the medici- 
 nal intention, to ufe pure fpirit of nitre, in the 
 preparation here advifed, from whence one 
 regular effeft may be obtained : and, with re- 
 fpedt to the beautiful appearance, fo neceflary 
 to the faleable condition of this medicine, it 
 will be found equally advantageous, when con- 
 ducted in the manner below directed. 
 
 Improved procefs for making the red precipitate 
 of mercury. 
 
 Take, of quickfilver, and pure fpirit of 
 nitre, equal quantities : put them into a 
 mattrafs, with a long neck ; and place them 
 in a digefting heat ; fhaking the mattrafir* 
 frequently, till the quickfilver be wholly 
 diffolved, (that is to fay, converted wholly 
 into a tranfparent fluid \ or partly into 
 fuch fluid, and partly into a mafs of white 
 fait) : put this folution, and fait, into a 
 
 long 
 
Chemical Preparations. 237 
 long fmall cucurbit ; and place it in a fand 
 heat, where the bottom of the cucurbit may- 
 receive a confiderable heat : fit a proper 
 glafs head, and receiver, to the cucurbit ; 
 and diftill off all the fluid that will come 
 over : when the fumes appear to rife very 
 fparingly, take off the head of the cucur- 
 bit ; and, by fome proper inflrument, draw 
 out fome of the contents, which will now 
 be the red precipitate 5 and examine, if, on 
 cooling, it appear of a fine red colour ; in 
 which cafe, lay a tile on the mouth of the 
 cucurbit, and raife it gradually in the fand, 
 fo as to prevent its fuffering a*iy longer the 
 a£tion of a ftrong heat$ but, if, on the 
 examination, it appear of a yellow, or 
 orange colour, and not fo crimfon as it 
 ought to be, on comparing it with a pro- 
 per fpecimen,) which lhould be always had, 
 in order to the forming a better judgment,) 
 Hie head fhould be put again on the cucur- 
 , bit, but without the trouble of luting, and 
 the heat fhould be continued again for fome 
 time, till, on further examination, by the 
 fame means, the precipitate be found to be 
 
 of 
 
238 Chemical Preparations. 
 of the proper colour : when, the cucurbit 
 having been immediately raifed out of the 
 great heat, and fufFered to cool, the con- 
 tents muft be taken out ; and broken into 
 an equal grofs powder 5 but not levigated, or 
 reduced to a finer ftate. 
 
 Note. 
 
 By this method, the red precipitate will not 
 only be made as cheap, and equally beautiful, 
 in its appearance, as with the trouble of the 
 fubordinate procefs for the compound of aqua 
 fortis ; but its medicinal qualities will be al- 
 ways limilar and equal, both in the nature and 
 force, of their operation ; which is certainly of 
 great confequence at prefent, as this prepara- 
 tion is ufed internally by many, and even given 
 very freely, with refped: to the largenefs of the 
 dofe : whereas, when aqua fortis is employed 
 in the preparation, in the place of fpirit of ni- 
 tre, an uncertain quantity of turpcth mineral 
 will, of courfe, be produced : and, in many 
 cafes, may operate in a manner very contrary 
 to the intention of the medicine. -^ 
 
 It is neceflary, that pure quickfilver be er^ 
 ployed as well for this, as the other precipitates* 
 
 The particular appearance of red precipitate, 
 both with regard to its bright red colour, and 
 the fparkling particles, it feems to be compofed 
 of, prevent it from being fo frequently adul- 
 terated, as it otherwife would be : but it is, 
 
 never- 
 
Chemical Preparations. 239 
 
 nevertheless, fometimes fophifticated with red 
 lead, finely levigated, and mixed with cinna- 
 bar, or vermilion ; which, together, imitate the 
 colour nearly enough to deceive any, who 
 have not an exaft remembrance of the red pre- 
 cipitate. Where the fparkling appearance, or 
 bright colour, therefore, feem wanting, and 
 there is any reafon to fufpeit a fraud of this 
 kind, a fmall quantity, of the parcel fufpedted, 
 may be put into a crucible, with a little char- 
 coal duft : and covered by means of another 
 leflfer crucible inverted 3 and, being ex'pofed to 
 a heat fufficient to fufe lead, and continued 
 fo for fome time, the red lead, if there be any, 
 will be reduced ; and regain its proper metal- 
 line form : and, if another quantity be put on 
 a red-hot poker, the immediate fublimation of 
 the cinnabar, in copious fumes, will readily 
 betray its prefence ; if the red precipitate in 
 queftion has been fophifticated with it. 
 
 Tellow emetic mercury, or turpeth mineral. 
 
 Put any quantity of quickfilver into a 
 glafs -, and pour on it double its weight of 
 oil of vitriol : heat the mixture, by flow 
 degrees, till it boil ; and continue it in that 
 ftate, till only a white mafs be found at the 
 bottom ; which, the fire being increafed, 
 muft be made perfectly dry : this mafs, 
 
 on 
 
240 Chemical Preparations* 
 on the pouring water on it, will immedi- 
 ately turn intenfely yellow ; and fall to 
 powder : let it be ground with this wa- 
 ter, for a confiderable time, in a glafs mor- 
 tar ; and, after the powder has fubfided, 
 the water muft be poured off; and fucceflive 
 quantities added, till it be intirely fweet. 
 
 Note. 
 
 The proportion of the oil of vitriol to the 
 quickfilver has always been very erroneous, in 
 all the procefles given for this preparation. 
 The college of Edinburg diredl four to one : 
 and the college of London, in the procefs here 
 given, though they have ordered only half that 
 quantity, have yet, neverthelefs, more than 
 doubled what is really neceflary to be ufed. 
 This will appear evident on the leaft confidera- 
 tion, that the adding more oil of vitriol to the 
 quickfilver, than can ad: on it, muft be entirely 
 needlefs : and lefs than the proportion of acid, 
 contained in an equal quantity of the oil of 
 vitriol, is fufficient to form the quickfilver into 
 a perfect fait ; as we fee in the cafe of fpirit of 
 -nitre, in the preparation of the red precipitate ; 
 after which neutralization, no further change 
 can be made by any operation of the acid on 
 it. No more oil of vitriol fhould, therefore, 
 be ufed than will combine with the quickfilver; 
 forthough, at the prefent price, the wafte is a 
 
 matter 
 
Chemical Preparations. 241 
 
 matter of no great confequence ; yet the tedi- 
 oufnefs of bringing over fo great a quantity of 
 oil of vitriol, that requires a very ftrong 
 heat to raife it, and is with difficulty, indeed, 
 brought over at all, in a fand heat, together 
 with the neceffity, which the redundant acid, 
 that will remain with the calx, when this 
 quantity is ufed, produces of wafhing the tur- 
 peth with feveral frefh quantities of water, to 
 the lofs of a confiderable part of it ? are very 
 ftrong objections, againft the wantonly em- 
 ploying more than the due preparation of the 
 medicine makes requisite* 
 
 The pouring fucceffive quantities of water 
 on the calx, is, likewife, both needlefs, and 
 wafteful : for almoft the whole quantity of 
 the turpeth might, in time, be wafhed away 
 by this means ; the quickfilver, being, in faft, 
 reduced to the ftate of a fait, though of a 
 kind very difficultly foluble. 
 
 The end of this wafhing cannot, therefore, 
 properly be any other than the freeing the calx 
 from any redundant acid ; which may be, to 
 a certain degree, much better done by employ- 
 ing fo great a heat in the calcination, as may 
 drive off all the acid, that is not fixed by the 
 quickfilver ; after which, the edulcoration may 
 be fufficiently perfected by fuch an ablution, 
 as will make very little wafte of the turpeth : 
 the following procefs will, therefore, afford a 
 greater produce of turpeth equally good : 
 though prepared with lefs expence, and much 
 
 kiefs trouble. 
 
242 Chemical Preparations. 
 
 More expedite and profitable method of pre- 
 paring the turpeth mineral. 
 
 Take, of purified quickfilver, and oil of 
 vitriol, equal parts : put them into a retort, 
 with a low neck ; and place it in a fand 
 heat : diftill off all the fluid, which will 
 come over ; urging it at laft with a very 
 ftrong heat : take the mafs, which remains, 
 after the diftillation, in the retort, and 
 break it to powder; water being poured on 
 it ; which will immediately convert it, from 
 a white to a yellow colour : let it be well 
 ground with this water, which muft be 
 afterwards, the powder having fubfided, 
 poured off from it ; and a frefh quantity 
 Tupplied 3 the faille fubfequent treatment 
 being repeated : the powder muft be then 
 freed, from the remaining fluid, by putting 
 it into a proper filter with paper, atld a lin- 
 nen cloth ; and afterwards dried on a board. 
 
 Note. 
 
 The quickfilver ought to be proved, before 
 it i$"ufed for this purpole ; and, if any adul- 
 teration be found, it ihould be purified by diftil- 
 lation. 
 
Chemical Preparations. 1243 
 
 latiori." It is very rare, that the turpeth is at- 
 tempted to be adulterated : hecaufe the price 
 of it is -not 'great j and no other matter could 
 be commixt with it, which would not deprave 
 the colour,' or diicover itfelf by other appear- 
 ances. The "beft method, therefore, of guard- 
 ing againft any imposition, with refpedt to this 
 medicine, is to have a fpecimen of fuch as is 
 perfect at hand j and to compare any fufpe&ed 
 parcel with it; which, if it differ not in the 
 bright yellow colour, may be with certainty 
 concluded to be unfophifticated. 
 
 Precipitate per fe. 
 
 Let purified quickfilver be placed, in a 
 fand heat, for fever&l months, in # proper 
 glafs, with a fmall hole, by which the air 
 may have accefs • and let it remain, in that 
 "ffate, till It be calcined into a red powder, 
 
 'Note. 
 
 This will be much fhortned by performing 
 it in the glafs defcribed p. 49 > where, by the 
 greatly intr'eafing the furface of the mercury 
 and promoting the influx of air by the tubes in- 
 ferted in the lower part of the glafs, the opera- 
 tion wiihbe greatly accelerated: but, in this 
 "cafe, the glafs rauft not be furrounded with 
 land, but placed in a fituation where the bot- 
 tom of it may be heated to a proper degree, 
 R 2 without 
 
244 Chemical Preparations. 
 
 without any iblid medium furrounding it, 
 which is no way neceflary. 
 
 As the keeping a conftant fand heat, for the 
 effecting this procefs, which requires fo great a 
 length of time, would be attended with great 
 expence, and trouble, it is much better to pro- 
 cure the glafs to be placed in a proper hole in 
 lome of the outward parts of a glafs-maker's, 
 or malt-diftiller's furnace, where it will under- 
 go a due heat : and by this method, the opera- 
 tion will be equally well performed ; and all 
 the expence, and trouble, of keeping a fire, 
 on purpofe, intirely faved. 
 
 JEthiops miner alts. 
 
 Take, of flowers of fulphur, and of 
 purified quickfilver, each equal quantities ; 
 grind them well together, in a glafs mortar, 
 till they be incorporated into a black powder. 
 
 Note. 
 
 The moft ufual fophiftication of this me- 
 dicine is, by increafing the quantity of the ful- 
 jbhur; which may be difcovered by revivifying 
 the mercury by diftillation ; or, with lefs trou- 
 ble, by boiling two or three ounces, or any 
 known quantity, of the fufpe&ed parcel, in 
 foap lees ; by which means, the quickfilver 
 being feparated, it may be weighed ; and its 
 proportion to the quantity it was extracted from 
 
 known. 
 
Chemical Preparations. 245 
 
 known. This will, likewife, difcover if it be 
 adulterated by any other mixture; for, the ful- 
 phur being diflblved in the lye, and the quick- 
 filver reduced to its metalline ftate, the other 
 heterogeneous matter will of courfe be diftin- 
 guifhable. 
 
 There is a method for the preparation of 
 sethiops mineralis fometimes praftifed, to fave 
 the trouble of grinding them together, till 
 they incorporate \ which is as follows. 
 
 Quicker method of preparing the cethiops 
 mineralis. 
 
 Take, of quickfilver, and fulphur, equal 
 parts -, melt the fulphur, taking care that 
 it do not take fire : when melted, add to 
 it the quickfilver, very gradually, ftirring 
 them well together : and, if the mixture 
 take fire, from their effervefcence, extin- 
 guifh it immediately, by throwing a wet 
 cloth over the veffel : when the mixture 
 is cold, levigate it. 
 
 Note. 
 
 This is, by fome, thought a fhorter, and 
 
 better, method than the other, of mixing the 
 
 ingredients of the aethiops mineralis : but there 
 
 is very little, if any, trouble faved by it y and 
 
 R3 it 
 
246 Chemical Preparations. 
 
 it is very dubious, whether the qualities ©f the 
 medicine may not be altered by this method of 
 preparation ; efpecially, as it is impoffible to re- 
 duce the mafs of the united quickfilver, and 
 fulphur, to fo fine a powder, by any mechani- 
 cal method of levigation, as the other will be, 
 neceflarily, from the manner, in which the 
 parts of the fulphur are divided, by the fubli- 
 mation, in the forming it into the flowers. 
 
 Fictitious cinnabar. 
 
 Take, of purified quickfilver, twenty five 
 ounces; of fulphur, nine ounces : melt the 
 fulphur 5 and add the quickfilver to it ; 
 and, if the mixture take fire, extinguifh 
 it by covering the veffel : afterwards, let 
 the mafs be reduced to powder, and fub- 
 limed. 
 
 Note. 
 
 This fublimation fhould be performed in a 
 coated body of glafs, hung in the naked fire : 
 the fufficiency of a fand heat being very pre- 
 carious. 
 
 The quantity of iiilphur, here dire&ed, is 
 larger than has been generally prefcribed, 
 when this preparation has been intended for 
 medicinal ufe : but the far greatefi: part of tlxe 
 fi&itious cinnabar, being defigned for the pur- 
 pofes of painting, where it is ufed under the 
 
 name 
 
Chemical Preparations. £47 
 
 name of vermillion, both the augmentation of 
 the profit, from the low price of the fulphur ? 
 and the improvement of the coloijr, have in- 
 duced the preparers to enlarge the proportion 
 of fulphur to at leaft one third. 
 
 The flowers of fulphur, though not directed 
 in this procefs of the college, fhould always 
 be ufed : for, if the roil fulphur be fubftituted, 
 in the place of them, and fhould happen to 
 be adulterated, as is very frequently the cafe, 
 with coarfe refin, the beauty, at leaft, of the 
 cinnabar would be vaftly impaired. 
 
 The manner of fublimation is, likewife, of 
 great confequence, to the fine colour of the 
 cinnabar ; the producing which is a profitable 
 fecret to thofe, who manufacture the vermi- 
 lion : it lies principally in raifing the fumes of 
 the cinnabar fo quick, that no part may fettle 
 in flowers ; but the whole form itfelf accord- 
 ing to that fpecific texture, which appertains to 
 this fubftan.ce ; in which particular, it corre- 
 fponds with falts, that if condenfed in fuch a 
 degree of heat, as fuffers the particles to coa- 
 lefce as they would in a fluid ftate, form chry- 
 ftals ; but if, in a lefs, they fettle without exert- 
 ing their fpecific attraction, and become only 
 that kind of powder we call flowers. The 
 following method may, therefore, be advan- 
 tageoufly perfued, where cinnabar is prepared 
 as vermilion ; and, for medicinal purpofes, its 
 difference, from that of the college prepared 
 according to the procefs above, will not be 
 very material ; as there are no data, from 
 
 R 4 whence 
 
'248 Chemical Preparations* 
 
 whence we can draw any conclufions, what 
 proportion of the quickfilver, and fulphur, 
 would produce the moft efficacious medicine. 
 
 Method of preparing cinnabar, particularly 
 with a view to the forming vermilion of a 
 very beautiful colour. 
 
 Take, of quickfilver, eighteen pounds, of 
 flowers of fulphur fix pounds : melt the 
 fulphur in an earthen pot ; and pour in the 
 quickfilver, very gradually ; ftirring them 
 together with a tobacco-pipe ; and, if, from 
 the effervefcence on adding the laft quantity 
 of the quickfilver, they take fire, immedi- 
 ately extinguifh it by throwing a wet cloth 
 over the vefTel : when the mixt mafs is cold, 
 powder it ; fo that the feveral parts fliall be 
 well mixt together ; but it is not neceffary 
 to reduce it by levigation to an impalpable 
 {late : having then prepared an oblong glafs 
 body, by coating it well with fire lute, over 
 the whole furface of the glafs, and work- 
 ing a proper rim of the fame round it, fo 
 that it may hang in fuch manner, that one 
 half ,of it may be expofed to the fire within 
 tl;e cavity of the furnace, let the powdered 
 
 l mafs 
 
Chemical Preparations. 249 
 mafs be put into it, fo as to fill the part, that 
 is within the furnace $ and a piece of broken 
 tile be laid over the mouth of the glafs: 
 fublime the cinnabar then, with as ftrong a 
 heat as may be ufed without blowing the 
 fumes of the cinnabar out of the mouth of 
 the glafs ; and, if there be any danger, 
 that the fublimed cake fhould form itfelf fo 
 in the mouth, as to flop up all vent, lift up 
 the tile at proper intervals ; and, with the 
 end of a tobacco-pipe, preferve fome paf- 
 fage, left, on too great an augmentation of 
 the heat, the confined vapour fhould burft 
 the glafs: when the fublimation is over, 
 which may be perceived by the abatement 
 of heat in the upper part of the body, dif- 
 continue the fire ; and, when the matter 
 contained in the glafs is cold, take it out ; 
 and feparate from it, any part, which ap- 
 pears diffimilar to the reft : powder then 
 the perfect part which is defigned to be 
 ufed, as vermilion; and keep what may 
 be necefTary for medicinal ufes, in lumps of 
 the fublimed cake. 
 
 
 Note. 
 
t$o Chemical Preparation 
 
 Note. 
 
 The vermilion Should be levigated as finely 
 as pofilble : for nothing contributes more 
 to its beautiful colour, as well as its excel- 
 lence in other refpefts, than the finenefs of 
 its powder. It is genepally tevigated by means 
 of a hand mill, where confiderable quantities 
 ^re manufactured ; but it may be rendered 
 more impalpable, by the ufe of the muller and 
 levigating ftone, than any mill can effecft 
 
 The cinnabar, deilgned for medicinal ufe, 
 fhould be procured by thole, who ufe it in an 
 unlevigated ftate ; and powdered by them- 
 felves, to prevent the fophiftication, by red- 
 lead, fo frequently praftifed, where it is fold in 
 the ftate of powder. This fraud is greatly 
 perfued by the dealers in vermilion ; as it is 
 difficult to diftinguifh by the appearance, or 
 immediately even in the ufe of it, the adul- 
 terate from the pure j but it is very injurious te> 
 the qualities of the paint, made of it 5 for, 
 whereas the genuine vermilion would retain 
 its beauty a long time ; the red-lead, on the 
 contrary, foon turns black; and, when mixt 
 with the other, confequently, foon deftroys its 
 brightnefs. 
 
 This fophiftication may, however, be eafily 
 detected by very fimple means, in the follow- 
 ing way. 
 
 Method 
 
Chemjcaj, Preparations. 251 
 
 Method of detecting the adulteration of cinna- 
 bar, or vermilion^ by the (itfmixtyi'e of red- 
 lead. 
 
 Take a fmall, but known, quantity of 
 the cinnabar, or vermilipn, fufpe&ed to be 
 adulterated -, and put it into a crucible ;, 
 having firft mixt with it about the fame 
 quantity, in bulk, of charcoal duft : put the 
 crucible in a common fire ; having covered it 
 with another lefler crucible, inverted - y and 
 give a heat Efficient to fufe lead : when the 
 crucible, being taken out of the fire, fhould 
 be well fhaken by ftriking it againft the 
 ground. If the fufpe£ted adulteration has 
 been pra6lifed, the lead will be found, rer- 
 duced to its metalline Hate, in the bottom of 
 the crucible ; and, being weighed, and com- 
 pared with the quantity of cinnabar put 
 into the crucible, the proportion of the 
 adulteration maybe thence certainly known : 
 but, if no lead be found in the cruciblp, it 
 may be fafely inferred, that no red-lead had 
 been commixt with the cinnabar. 
 
 Notu 
 
252 Chemical Preparations. 
 
 Note. 
 
 The adulteration of cinnabar, by red-lead, 
 maybe difcovered, if in a greater degree, by the 
 comparing the fufpecfted parcel, with a fpeci- 
 men of the pure : for though the red-lead does 
 not greatly take off from the brightnefs of the 
 colour of the vermilion; yet it gives a tinge of 
 orange colour to it, not found in the genuine; 
 which will, confequently, appear different from 
 the adulterate, by its more crimfon hue. 
 
 Cinnabar of antimony. 
 
 Take, of antimony, one pound, of corro- 
 five fublimate. two pounds: powder them fe- 
 parately ; and let them be thoroughly mix- 
 ed, and diftilled, in a fand heat ; being 
 contained in a retort, whofe neck muft be 
 large : fublime what remains, in the re- 
 tort, in a coated mattrafs, placed in the 
 open fire. 
 
 Note. 
 
 The proportion of fublimate here directed, 
 in this procefs, which is that of the college, 
 differs from thofe prefcribed in the former 
 procefles : but it is, probably, with a view to 
 the antimonial cauftic that is produced along 
 with the cinnabar, they have made this devia- 
 tion ; 
 
Chemical Preparations, 253 
 
 tion ; for the quantity of cinnabar will be 
 diminifhed, to the lofs of the preparer with- 
 out any demonftrable, or even rationally pre- 
 fumptive improvement of the medicine. 
 
 The procefs is, likewife, contrary to the 
 former pra&ice, divided into two operations ; 
 the firft for diftilling the butter of antimony, 
 or antimonial cauftic, in a retort, I with a fand 
 heat , the other for fubliming, in a mattrafs, 
 the cinnabar, being the caput mortuum, or 
 recrement remaining after the diftillation ; 
 inftead of performing the whole together, in 
 a coated retort, in the naked fire. Where 
 large quantities are to be prepared, this is cer- 
 tainly the more expedient method 5 for, when 
 both operations are performed in the fame 
 veflel, the cinnabar butter, are very apt to be 
 commixt with each other, and the retort ex- 
 tremely liable to be cracked by the augmented 
 heat, required for fubliming the cinnabar. 
 
 But though thefubfequent fublimation of the 
 cinnabar, in a diftindt veffel from that in which 
 the butter is diftilled, may be confidered as an 
 improvement ; yet the choice of a mattrafs, as 
 the proper veffel for it, is certainly a great er- 
 ror ; as the round figure of a mattrafs, though 
 very fuitable to fome kind of fublimations in 
 fand-pots, is by no means convenient for fuch 
 glafles, as are fixed in the cavity of the fur- 
 nace itfelf , the nearnefs of the uppermoft part 
 above the fire to that which muft be furrounded 
 by it being fo great, that it is impoffible to give 
 the due fubliming heat to the orie, without 
 - - rendering 
 
254 Chemical PkfepAftAfiONS. 
 rendering the other hotter than the degree pro~ 
 per for condenfatioh ; and, therefore, either the 
 heat mull be fo fuppreffed, that the Operation 
 cannot be duly advanced, or the fumes of the 
 fubliming matter would be driven otit of the 
 neck of the veffel; of, collecting in it, choak 
 up the vent, arid bufft the glafs. A body, 
 therefore, of oblong form, which admits of a 
 due distance betwixt the upper and lower parts, 
 as well as of the room neceffary for the rihi of 
 lute, by which it niuft be huiig, is far prefera- 
 ble :• but, if the quantity be not gfeat, it is 
 proper to have fome kind of dome, cff cover, 
 to ' the furnace, by which the body may be 
 hung ; fince it would, otherwife, be unavoida- 
 ble, to ufe a large body ; as ho other could be 
 fixed ill a common fized furnace : and this 
 would render the fublimed cake of cinnabar fo 
 thin, as not to have the falable appeatance. 
 
 This cover, or dome, fot* hanging the fub- 
 liming veflel, may be a flat rim of caft iron laid 
 over the furnace, and contracting the opening 
 into it, to the widenefs proper for the purpofe, 
 fo as to fuffer the coated body, to harig upon it, 
 by the rim of lute worked r6uhd it for that 
 end. 
 
 The trouble and expence of making the 
 cinnabar of antimony from crude antimony, 
 and fublimate, (the butter, or antimonial 
 cauftic, the other produce of this operation 
 being feldom called for,) have occafioned the 
 feeking other 'methods of preparing it ; as 
 well as fubftitutions of other kinds of cinna- 
 bar 
 
Chemical Preparations. 253 
 
 bar for it: amongft which, the following is the 
 oldeft, and has been the mofl pfa&ifed. 
 
 Common preparation of cinnabar qf antimony, 
 without the mercury fublinrntez 
 
 Take, of crude mfercury, thirteen dunces -, 
 of 'florets- of lulphtir, five oiirices, arid of 
 crude antimony, one ounce and a half; 
 mil them wel* together ; and fublime them, 
 in a coated veffel, ill a naked fire. 
 
 Note. 
 
 Though this has been vainly fuppofed to 
 differ from other fictitious cinnabar, by the 
 addition of the antimony : yet it is in every 
 refpecS the fame ; the antimony not being any 
 way analyzed, or yielding any part of its ful- 
 phur to the mercury, by this treatment. And, 
 indeed, if the cinnabar be prepared with this 
 proportion of fulphur, it will not have, in the 
 leaft degree, that appearance, which diftin- 
 guifhes the cinnabar of antimony from com- 
 riion fi&itious cinnabar : the firfl being formed 
 in long needles like fhoots, which feem re- 
 gularly joined to each other, in a parallel direc- 
 tion ; but the latter, in fhort irregular ftria, 
 and of a much more compact, and lefs friable 
 texture, 
 
 2 This 
 
256 Chemical Preparations. 
 
 This irrefemblance may, however, be a- 
 voided; and a cinnabar prepared, by better 
 adopting the proportion of the quickfilver and 
 folphur to this purpofe, which will be indi- 
 ftinguifhable from the true cinnabar of an- 
 timony made with fublimate, according to the 
 above given procefs ; and without the ufe of 
 any antimony at all ; of which, however, a 
 fmall quantity may be put in to fave the ho- 
 nour of thofe, who are fcrupuloufly nice in 
 the manner of deceiving. 
 
 The following is the moft expedite method 
 of preparing this kind of cinnabar. 
 
 Method of preparing cinnabar exaSlly refem- 
 bling the cinnabar of antimony made with 
 fublimate. 
 
 Take, of quickfilver, fix pounds, of flowers 
 of fulphur, one pound : incorporate the 
 quickfilver with the melted fulphur ; and, 
 having pounded the mafs, fo that the feve- 
 ral parts of it may be well mixt together, 
 put it in a coated body, of which it will fill 
 almoft half; and fublime it, in the naked 
 fire : taking away, after the fublimation, 
 fuch parts as have not the proper ftriated, or 
 needlelike appearance. 
 
 Note. 
 
Chemical Preparations. 2$J 
 
 Note. 
 
 The particular manner of conducing this 
 procefs, may be regulated by the directions 
 more particularly given before, in the procefs 
 for preparing the cinnabar for vermilion. 
 
 The cinnabar, prepared from this propor- 
 tion of quickfilver and fulphur, is, in every 
 refpeft, fimilar to that made from the fubli- 
 mate and crude antimony, and may be fubfti- 
 tuted for it, without any real injury to the me- 
 dicinal intention : for, notwithstanding the 
 manner of preparation, and the authority of 
 long ufage, there is really nothing more in the 
 cinnabar made from the fublimate and anti- 
 mony, fuppofing it intirely freed from the 
 butter, or antimonial cauftic, that arifes along 
 with it, than in that made from quickfilver and 
 common mineral fulphur : for the fulphur of 
 the antimony, which is the common mineral 
 fulphur, being feparated from the reguline part 
 of the antimony, combines with the quick- 
 filver in the fame manner, as any other por- 
 tion of fuch fulphur would ; and fuffers the 
 fpirit of fait, which the fublimate contains, to 
 raife with it the reguline part of the antimony; 
 the quickfilver, which is the other conftituent, 
 being left at liberty to combine with the fulphur. 
 Nor is it of any real confequence to add the 
 crude antimony to the quickfilver, and fulphur, 
 ufed in the procefs here given, even though 
 the quantity of fulphur be very fmall ; for 
 S without 
 
278 Chemical Preparations. 
 
 without the medium of the fpirit of fait, which 
 is added by ufing the fublimate, to feparate the 
 reguline part from the fulphur, they remain 
 combined ; and pailively fuffer the cinnabar to 
 be fublimed, and leave them in their intire 
 ftate ; without undergoing themfelves, or pro- 
 ducing any change in the cinnabar. 
 
 The cinnabar of antimony is fubjeit to the 
 fame adulterations as the fi&itious cinnabar ; 
 and they may be difcovered by the means be- 
 fore directed : but, if it be had unlevigated, and 
 the ftria appear like long needles, there can be 
 no room for either fufpe&ing any adulteration, 
 or fubftitution : unlefs of fiditious cinnabar, 
 prepared in fome manner parallel to that here 
 given for the imitation of cinnabar of antimony ; 
 againft which, there can be no guard, as they 
 are, in fa£t, the fame thing in every refpeft. 
 
 Regulus and fulphur auratum of antimony. 
 
 Take, of antimony, fixteen ounces, of 
 tartar, one pound, and of nitre, half a 
 pound; let them be feparately powdered, 
 and mixed well together : then let this 
 mixture be put, gradually, into a red-hot 
 crucible, fufed with a very ftrong fire , 
 and afterwards poured into a proper conic 
 mould. 
 
 The 
 
Chemical Preparations. 259 
 The metalline part, commonly called the 
 regulus of antimony, will fink below the 
 fcoria ; and muft be feparated from it. 
 
 The fcoria muft be diifolyed in water ; 
 and the folution filtered through* paper : 
 after which a precipitation muft be made, 
 from it, of the fulphur ; by dropping, in- 
 to it, fpirit of fea fait : and, laftly, the 
 precipitated matter muft be freed, from the 
 falts, by wafhing in water. 
 
 Note. 
 
 This is according to the college of Lon- 
 don ; and, indeed, is the old procefs given by 
 Lemery ; and, from him, by Quincy. The 
 method is fomething more expenfive than 
 neceflary ; becaufe the tartar and nitre might 
 be wholly omitted, if eight or ten ounces of 
 pearl-a{hes, or any fixt alkaline fait, were fub- 
 ftituted in the place of them, as they a£t no 
 other way advantageoufly, with refpecft to the 
 end of the procefs, than by producing a fixt 
 alkaline fait 3 and, in this cafe, the regulus 
 would be more du&ile j and, confequently, 
 more eafily formed into cups, or any other 
 figured veffel, for making the antimonial wine. 
 
 But, as the confumption of this kind of re- 
 gulus is very fmall, it is not of great confe- 
 quence which method is perfued. 
 
 S 2 But, 
 
260 Chemical Preparations. 
 
 But, if the fulphur auratum fhould be, how- 
 ever, demanded in any larger quantity, the ufe 
 of the pearl-afhes, inftead of the nitre and tar- 
 tar, would be found much more advantage- 
 ous \ and may be fubflituted in the following 
 manner. 
 
 Cheap and compendious method of producing 
 copioufly the fulphur auratum antimonij. 
 
 Take, of antimony, and any fixt alkaline 
 fait, equal parts : powder the antimony ; 
 and, having mixt it thoroughly with the 
 fait, put them into a crucible j and give 
 them a fufing heat : when they are tho- 
 roughly melted, pour the mafs into a deep 
 mold greafed ; and, when cold, feparate 
 the fcoria from the reguline part ; and boil 
 it, for fome time, in water, to difTolve the 
 fait : filter the folution through paper ; and, 
 afterwards, drop fpirit of fait, very gra- 
 dually, into it, fo long as it appears to pro- 
 duce any turbidnefs, or eftervefcence ; the 
 fulphur will be by this means precipitated, 
 which muil be waflied in feveral fucceffive 
 quantities of water ; and then feparated, 
 from the fluid, by means, firft of decanta- 
 
 tion. 
 
Chemical Preparations. 261 
 tion, when the fediment is perfectly fubfid- 
 ed > and afterwards of draining off the re- 
 maining moiflure through a filter, in which 
 a linnen cloth is laid over paper : and, be- 
 ing of due confiftence, it muft be, at laft, 
 dried on a board, in the fliade. 
 
 Note. 
 
 This method will produce much greater 
 quantities of the fulphur, than where nitre is 
 ufed : as a considerable part of what the an- 
 timony contains is destroyed in the deflagra- 
 tion y efpecially, where tartar is not at all, or 
 only Sparingly, ufed in the deflagration. 
 
 At prefent this improvement is of no great 
 moment, to the practice of commercial che- 
 miftry, as the demand for it is fmall : but 
 when, as may probably happen, fome time, 
 the fecrets of a certain great empiric fliall be 
 revealed to the world, and it fhall be found, 
 that many of his moft boafted cures were 
 owing to this remedy, it will doubtlefs be 
 brought, for at leaft fome time, into high 
 vogue ; and the demand for it fo increafed, as 
 may make it well worth while to inquire after 
 the eafieft means of producing it. 
 
 The regulus, prepared in this manner, will be, 
 perhaps, fuperior to all others, as well for me- 
 dicinal, as other purpoles : but where regulus of 
 antimony is wanted, for any other than medici- 
 nal ufes, it is ufually prepared with fteel : and, 
 S 3 indeed, 
 
262 Chemtcal Preparations. 
 indeed, that kind will equally well anfwer every 
 intention as a medicine : and is moftly fubfti- 
 tuted for the other ; from which, it has no 
 eilential difference; it being the fame, in effeft, 
 whether the redundant fulphur of the anti- 
 mony be attracted, from the proper metallic 
 part, by means of fixt alkaline falts, or iron. 
 
 The common method of preparing the 
 martial regulus, (as it is called,) is as follows. 
 
 Martial regulus ; or regulus of antimony pre- 
 pared with JleeL 
 
 Take, of fmall nails, two pounds and a 
 half : put them into a large crucible, placed 
 upon a tile, in a melting, or wind furnace; 
 let .the fire kindle about them gradually, till 
 the nails are ready to melt : then projedl, 
 by a large fpoonful at a time, of antimony, 
 one pound, of nitre, four ounces, and of 
 tartar two ounces, all powdered, and mixed 
 well together. Bury the crucible in char- 
 coal ; and, {hutting the door of the fur- 
 nace, let it (land in the ftrongeft fufion, 
 till the mixture it contains has done {park- 
 ling : then take it from the fire ; and pour 
 the matter into an iron mortar, made 
 hot, and previoufly greafed. When the 
 
 mafs 
 
Chemical Preparations. 263' 
 mafs is cold, beat off the fcoria from the 
 regulus. 
 
 Note. 
 
 This is the regulus as commonly ufed for 
 other than medicinal purpofes - y but for thofe, 
 it is generally directed to be converted into the 
 regulus ftellatus ; which is done, by repeated 
 fufions with additional quantities of nitre. 
 
 But where iron is ufed, the addition of nitre 
 and tartar is needlefs ; the iron being fufficient 
 to attrad: the redundant fulphur from the re- 
 guline part of the antimony : but the fcoria 
 formed by the fulphur and iron without falts, 
 being of an hard untraceable nature, it is diffi- 
 cult to feparate it from the regulus ; for which 
 reafon, it is proper to add a quantity, equal to 
 half the weight of the iron, of the fal enixum, 
 or caput mortuum, after the diftillation of 
 nitre; which, in moftelaboratories, is other- 
 wife generally thrown away : and this propor- 
 tion of fait will render it very eafy, by foaking 
 in water, to fcrape off all the fcoria without 
 any lofs of the regulus. 
 
 The quantity of iron is, iikewife, much more 
 than requifite : as an equal weight will be fully 
 fufficient to abforb the redundant fulphur : 
 the college of Edinburg have directed only 
 half the weight : but then they have greatly 
 enlarged the proportion of nitre and tartar; the 
 alkaline fait, formed from which, make up for 
 the deficience of the iron. This , however, 
 
 S 4 can 
 
264 Chemical Preparations. 
 
 can fcarccly be called the martial regulus, or 
 preparation of the regulus of antimony by 
 ileel y becaufe, if the iron were omitted, the 
 operation would fucceed equally well : as ap- 
 pears from their procefs for the common regu- 
 lus, in which, the proportion of the nitre and 
 tartar are the fame as for this, and no other 
 circumstances different, befides the omiffion of 
 the iron. 
 
 The martial regulus may be, therefore, beft 
 prepared by the following method. 
 
 More profitable preparation of the regulus of 
 antimony \ by means of feel. 
 
 Take, of crude antimony, and iron nails, 
 each one pound, of the fal enixum, or ca- 
 put mortuum, after the diftillation of fpirit 
 of nitre by Glauber's method, half a pound, 
 of pearl-afhes, or any fixt alkaline fait, 
 two ounces : put the iron nails into a cru- 
 cible, and place it in a wind furnace ; and, 
 when it is white hot, throw in the anti- 
 mony and falts powdered together, by a 
 large fpoonful at a time >■ giving the mix- 
 ture time to recover its heat betwixt each 
 addition : when -the whole is commixt, 
 clofe the door of the furnace, and continue 
 
 the 
 
Chemical Preparations. 265 
 the mixture in a fufing heat, for fome mi- 
 nutes ; and then pour it out, into a deep 
 copper mould, a little deviating from the 
 cylindrical form, (that the mafs of metal 
 may the more eafily be turned out of it), 
 heated, and greafed -, and, when it is cold, 
 let the end of it, where the fcoria adhere, 
 be foaked, for fome time, in water, which 
 will make them crumble off, without a 
 neceffity of breaking the caft of the regulus. 
 
 Note. 
 
 It is by methods fimilar to this, that regulus 
 of antimony is prepared for the ufe of the 
 pewterers, by thofe, who make it their parti- 
 cular bufinefs : and it is indifferent, by what 
 means, the common fulphur, contained in the 
 crude antimony, is extracted from it : or whe- 
 ther iron, or the fixt alkaline fait, produced by 
 the addition of nitre and tartar, be the inftru- 
 ment. But where nitre is added to the fufed 
 regulus without tartar ; or with a great excefs 
 in quantity, as in the preparation of the ftel- 
 fate regulus, as it is called, an effential dif- 
 ference is wrought : for the nitre destroying, 
 or the fixt alkaline fait, produced by it, ab- 
 forbing, more of the fulphur of the regulus, 
 an approximation is made towards that ftate, 
 in which antimony is moft forcible in its ope- 
 ration 
 
266 Chemical Preparations, 
 ration on the human confutation; as it is only, 
 by a perfed: calcination of the fixed fulphur, 
 the glafs of antimony, the moft powerful of all 
 the preparations, is formed. 
 
 It was from this difference, therefore, that all 
 the old proceffes direft the continuation of thofe 
 parts of the operation, which they thought ne- 
 ceflary for the producing what is now called 
 the ftellated antimony, without diftinguifhing 
 it by any name from the lefs calcined martial 
 regulus ; but giving this the name of martial 
 to diftinguifh it from what is made by means 
 of nitre and tartar ; which they called the 
 common : and as, therefore, the regulus is un- 
 doubtedly of a more powerful operation, as a 
 medicine, in this ftate, it ought to be reduced 
 to it ; where the intention of the prefcriber is 
 to have it fo. But as that part of the com- 
 mon proceffes, which refpe&s the convert- 
 ing the martial- regulus, produced as above, 
 into the ftellated kind, are unneceffarily 
 complex and laborious, I will, after giving 
 them, as they are generally directed, fhew the 
 moft fimple and expedite method of pre- 
 paring it 
 
 Preparation of the ftellated regulus of anti- 
 mony, from the martial regulus. 
 
 Take, of the martial regulus, freed from 
 the fcoria, one pound : put it, in a crucible, 
 
 into 
 
Chemical Preparations. 267 
 into a wind furnace ; and, being !n fufion, 
 add to it two ounces of nitre powdered : 
 let it continue in the fire, till all appear- 
 ance of the deflagration be over ; and then 
 caft it into a mould, as before : let this 
 operation be repeated, three or four times ; 
 the fame quantity of nitre being ufed ; 
 and care being taken, that the regulus be 
 in perfeft fufion, the laft time the nitre is 
 added : the fcoria being then taken off, 
 after the regulus is cold, the appearance of 
 a ftar will be found on the furface. 
 
 N. B. In order to have the flar fhew it- 
 felf more favourably, the regulus may be 
 caft, the laft time, into the bottom of a 
 mortar, previoufly greafed, inftead of the 
 deep mould. 
 
 Note. 
 
 The Edinburg college order equal parts of 
 nitre, and tartar, to be ufed ; and a great pro- 
 portion to be employed ; but this can anfwer 
 no end; for the greateft part of the nitre, de- 
 flagrating with the fulphur, in the tartar, has 
 no a&ion on the antimony ; producing only a 
 proportionable quantity of fixt alkaline fait, 
 which is of no effeft here : the end of this 
 repeated fufion, with nitre, being only to de- 
 stroy 
 
268 Chemical Preparations^ 
 ftroy a part of the fulphur of the antimony; 
 by which means the ftellated appearance is 
 produced. 
 
 The repeated operations of fuficn, and de- 
 flagration, are unneceflary ; for, with lefs nitre, 
 and an addition of fome iixt alkaline fait, to 
 affift in abforbing the remains of the refluent 
 fulphur, one fufion may be made to firve the 
 end equally well, by the following method. 
 
 More compendious and expedite method of pre- 
 paring the Jiellated regulus of antimony , from 
 the martial regains. 
 
 Take, of the martial regulus, freed from 
 the fcoria, one pound : being put into a cru- 
 cible, fet it in a wind furnace ; and, when 
 thoroughly fufed, throw into it, by a fpoon- 
 ful at a time, of nitre, two ounces, and of 
 any fixt alkaline, three ounces \ ftirring the 
 mixture well together, with the end of a 
 tobacco-pipe, betwixt each addition of the 
 nitre and alkaline fait, as well as when the 
 whole is thrown in. Let the matter re- 
 main, for fome time after, in ftrong fufion ; 
 and then caft it into an iron mortar greafed ; 
 and, when cold, . take off the fcoria. 
 
 ; £ Note, 
 
Chemical Preparations. 269 
 
 Note. 
 
 By this means, the ftellated regulus may be 
 produced with greatly lefs trouble and expence : 
 for the quantity of nitre ufed will be fufficient 
 to deftroy the due proportion of the proper ful- 
 phur of the regulus : and the alkaline fait will 
 abforb any remainder of the common fulphur : 
 and if the ftellated appearance fhould not be 
 found, which will fometimes be the cafe, in 
 every method of preparation, it is not in the 
 leaft material, with refpeft to the medicinal 
 efficacy of the regulus. 
 
 Though cuftom has eftablifhed the ufe of 
 nitre, in this further preparation of the regulus, 
 after the firft precipitation of it from the ful- 
 phur in the crude antimony : yet, the fluxing 
 it twice with fixt alkaline falts, mixed with a 
 lit le crude tartar, is much the beft way of 
 further purifying the regulus ; and it has this 
 further good effeft, where it is wanted for 
 making the antimonial wine, that the texture is 
 not rendered fo unfit for that ufe 3 as it remains 
 du&ile ; and may be eafily caft into any fuch 
 kind of form. 
 
 Crocus antimony, commonly called crocus me- 
 tallorum. 
 
 Take, of antimony, and nitre, an equal 
 weight: being feparately powdered, let them 
 
 be 
 
270 Chemical Preparations. 
 be well mixed together ; and put, by degrees, 
 into a red hot crucible, where they may be 
 fufed : having poured them out of the 
 crucible, let the fcoria be taken off from 
 them. The mafs will then appear of vari- 
 ous colours > and the longer it has continued 
 fufed in the fire, the more it will approach 
 to yellow. 
 
 Note. 
 
 This is the crocus antimonij of the college, 
 and of the old practice : but the modern pre- 
 parers of medicine have introduced another 
 kind, more profitably prepared by the ufing a 
 lefs proportion of nitre - y by which, not only a 
 faving is made, in the quantity of the deareft 
 ingredient ; but lefs of the fulphur of the an- 
 timony being deftroyed, the produce is necef- 
 farily greater. The fmall confumption, made 
 of this preparation in medicine, would not, 
 perhaps, have afforded any temptation to this 
 practice : but the crocus metallorum, being 
 one of the capital articles of the farriers, who 
 ufe every thing in great quantities, the demand 
 for it has been considerable enough to induce 
 the great dealers, to think of obtaining this, 
 as well as other articles, at the cheapeft rate 
 they could. 
 
 When the crocus metaliorum is prepared in 
 great quantities, there is, likewife, a much lefs 
 troubiefome and expenfive method of perform- 
 ing 
 
Chemical Preparations. 271 
 
 ing the deflagration, than by the ufe of any 
 furnace : which is by producing the neceflary 
 effed:, with refpedl to the fufion, by the heat 
 generated by the matter itfelf, in confequence 
 of the explofive a&ion of the nitre, and ful- 
 phur contained in the crude antimony j and 
 this explofive a&ion may be rendered more 
 efficacious, to this end, by the addition of a 
 fmall quantity of fea fait to the other ingre- 
 dients. The beft method of conducing this 
 operation, and the proportion of nitre generally 
 made ufe of, are as follows. 
 
 Method of preparing the common crocus metal- 
 lorum, without ufmg any furnace^ or em- 
 ploying any exterior heat. 
 
 Take, of crude antimony, fixteen pounds, 
 of nitre, fourteen pounds, of fea fait one 
 pound : powder the antimony and nitre 
 feparately -, and then mix them thoroughly 
 together, adding the common fait : put this 
 mixture into an iron pot, fuch as is Com- 
 monly ufed for boiling flefh, of a proper 
 fize \ and cover the pot with a fiat plate of 
 iron, or large ftone ; leaving, neverthelefs, 
 fome vent for the vapour to tranfpire : fet 
 the pot in fome open place in the air ; and 
 fet fire to the mixture contained in it, by 
 2 means 
 
272 Chemical Preparations, 
 means of an iron rod, or fmall end of a 
 tobacco pipe heated, and thruft into it ; 
 and let it continue to burn, till the fire ex- 
 tinguifhes of itfelf : when the eruption of 
 the fumes is fo abated, that it may be pro- 
 per to approach the pot, ftrike it feveral 
 times on different fides, that the concuflion 
 may make the melted metallic part feparate, 
 by its weight, from the fcoria : and then 
 fufxer it to fland till it be cold : the matter 
 being taken out of the pot, the fcoria muft 
 be feparated from the liver coloured mafs, 
 which is the crocus metallorum. 
 
 Note. 
 
 This is the common crocus metallorum, 
 which is ufually found in the fhops : it may 
 be diftinguifhed from that, *made accord- 
 ing to the regular proceffes, with equal parts 
 of nitre and antimony, by its being lefs yel- 
 low ; and having a more equal and liver like 
 appearance. It is efteemed lefs powerful in its 
 operation, as a medicine, on account of the ful- 
 phurs not being diminifhed in fo great a propor- 
 tion in it, as in the other \ and probably with 
 reafon : but, as there is a certain limitation, with 
 regard to this circumftance, fincethedeftroying 
 too much of the fulphur will weaken the 
 medicinal operation, as well as the leaving too 
 
 much 
 
Chemical Preparations. 27J 
 
 much undeftroyed, it is hot eafy to determine, 
 where the exaft degree lies : though the fufiorl 
 of equal parts of the crude antimony, and nitre,- 
 is faid to be the proportion moft likely to pro- 
 duce if. 
 
 Diaphoretic antimony* 
 
 Let powdered antimony be thoroughly 
 mixed with three times its weight of nitre % 
 and, gradually, put into a crucible juft be- 
 ginning to glow : then, the mixture being 
 taken from the fire, let it be purified by 
 wafhing in water, as well from the falts, as 
 from the groffer parts lefs perfectly calcined^ 
 
 Note. 
 
 This preparation ought to be made with 
 care : for, if the whole of the antimony be not 
 reduced to calx, extremely aftive qualities will 
 be found in it; and produce very unlocked fof, 
 and troublefoihe, effedts, in thofeto whom it is 
 given; 
 
 The moft material object of care irt the 
 preparation, fhould be the powdering finely, 
 and mixing thoroughly, the ingredients: for, if 
 that be done, ahd the matter be well ftirred 
 with the fmall end of a tobacco-pipe, the 
 calcination can hardly fail to be perfect ; but, 
 if, neverthelefs, there appear any parts, that 
 
 T will 
 
274 Chemical Preparations. 
 will not foften on their maceration in boiling 
 water, they fhould be feparated \ and, being 
 well powdered, may be added to the next 
 quantity of materials ufed for the fame pre- 
 paration. 
 
 The quickeft method to free the calx, from 
 the mafs of falts it is commixt with, is, after 
 cleanfing the outward part of the crucible, to 
 break it ; and put the whole into boiling wa- 
 ter, and continue it there, till all the calcined 
 matter will eafily feparate, from the crucible 
 by a knife, or fpatula, without fcraping : and, 
 when the fediment has fubfided perfeftly, the 
 parts of the broken crucible being previoufly 
 taken out, the water fhould be poured off; 
 and frefh quantities added, two or three times : 
 after which, to have the medicine in the great- 
 eft perfedtion, the fine powder fhould be fe- 
 parated by wafhing over, according to the 
 methods defcribed p. 62. 
 
 This medicine fhould never be taken from 
 the hands of any, in whom an abfolute confi- 
 dence cannot be placed : for, befides the dan- 
 ger that attends the giving fuch as is unduly 
 prepared, it is liable to be adulterated by any 
 cretaceous, or other fimilar matter, without any 
 means of detecting certainly the fraud. The 
 moil: probable method of perceiving fuch a fo- 
 phiftication is, by pouring ipirit of fait or nitre 
 on the powder, which will produce an effer- 
 vefcence, if chalk, white lead, or many other 
 fubftances likely to be ufed for this fophiffica- 
 tion, have been commixt with the calx of the 
 
 antimony ; 
 
Chemical Preparations 2j§ 
 
 Mtitimony : and, by this means, there is a 
 great chance of difcovering the adulteration, 
 as the acid fpirits have no effect on the calx it- 
 felf : but there are other fubftances which may 
 be ufed* that are intirely neutral with regard to 
 all acids : and, therefore, though this experi- 
 ment may be conclufive, in many cafes, that 
 there is an adulteration $ yet it is not demon- 
 fixative, that none has been pradifed, 
 
 Bezoar mineral. 
 
 Take, of the butter of antimony, three 
 ounces : drop upon it, flowly, the fame quan- 
 tity of fpirit of nitre : put the matter in a 
 retort or fmall body, into a fand heat - y and 
 draw off the fpirit : to the remaining dry 
 matter, found in the bottom of the retort, 
 or body, add two ounces more of the fpirit 
 of nitre ; diftilling off again, all that will 
 rife, as before : repeat the fame treatment 
 three times ; and then calcine the white 
 powder, in a crucible, for an hour y ufing 
 an intenfe heat : and edulcorate the calx 
 by wafhing with water. 
 
 Note. 
 
 The college of Edinburg, according for 
 Lemery and Thebaut, ufe only as much fpirit 
 
 T 2 of 
 
276 Chemical Preparations. 
 
 of nitre, as will eftervefce with the butter of 
 antimony, and there is no more neceffary. 
 
 They, alfo, direft the fire to be continued 
 for only half an hour, and to be intenfe in the 
 calcination ; omitting, likewife, the edulcora- 
 tion by wafhing; which is, indeed, rendered 
 needlefs, if the fire be intenfe ; as all faline 
 parts will be intirely expelled by it. 
 
 As this is nothing but a calx of antimony 
 produced by the deftruftion of the fulphur, by 
 means of the nitrous fpirit, the far greateft part 
 of the procefs is of no confequence ; and the 
 repetition of the addition, and feparation of fo 
 many fuccefiive quantities of fpirit of nitre, is 
 intirely needlefs. The following procefs has, 
 therefore, been given as preferable to the com- 
 mon ones, on account of fhortning the pre- 
 paration, by leaving out the fuperfluous parts 
 of it. 
 
 More expeditious method of preparing the bezoar 
 * mineral. 
 
 Take any quantity of butter of antimony ; 
 and drop it gradually into three times its 
 weight of fpirit of nitre: put it into a fmall 
 glafs body : fit on a head and draw off 
 the fpirit in a fand-heat : the remaining 
 dry matter muft, then, be put into a cruci- 
 ble j and calcined with a very ftrong fire. 
 
 Note. 
 
Chemical Preparations. 277 
 
 Note. 
 
 This is a much quicker way of performing 
 the procefs 5 but the quantity of fpirit of nitre 
 is far too large, and, if we take the liberty of 
 amending the procefs in one point, by reafon- 
 ing on principles, we fhould do it in all. If 
 we, therefore, confider the nature of the two 
 fubftances, we fhall fee, that no more fpirit of 
 nitre can be of any confequence, in the opera- 
 tion, than fo much as will combine with the 
 regulus contained in the butter of antimony : 
 for, after the regulus and fpirit are combined 
 in a certain proportion, the compound becomes 
 neutral to any further quantities of either of 
 its two elements ; and, whatever fpirit of ni- 
 tre, beyond the due proportion, is added, re- 
 mains commixt with it, in a pafiive (late, till 
 brought off in the diflillation, without having 
 produced any effedt on the matter left behind: 
 The true proportion, therefore, of the fpirit 
 of nitre, is fo much as will produce any effer- 
 vefcence on being dropt upon the butter ; which 
 fhould be carefully obferved in the mixing 
 them. 
 
 But there is yet another circumftance of 
 needlefs expence, in all the process for this 
 preparation ; which is the ufe of the butter of 
 antimony, inftead of the regulus ; as will ob- 
 vioufly appear, when we confider, of what 
 elements the butter of antimony confifts 5 an$ 
 how the fpirit of nitre afts on it to produce 
 T 3 the 
 
278 Chemical Preparations. 
 
 the bezoar mineral, When the fublimate and 
 antimony are commixt together, and heated, 
 in order to form the butter, the fpirit of fait, 
 one of the two corlfiituents of the fublimate, 
 attracted more powerfully by the reguiine part 
 of the antimony, than by the mercury, the other 
 conftituent leaves it, and combines with the 
 reguiine part of the antimony ; which is at the 
 fame time, by the fuperior attraction of the 
 mercury, feparated from the common fulphur 
 joined with it, in conftituting the crude anti-* 
 rnony ; and the mercury, and common fuU 
 phur, being thus freed from their former at- 
 traftives, combine and form the cinnabar, as 
 the fpirit of fait and regulus form the butter of 
 antimony 3 which being more volatile, or rather 
 lefs fixed, than the cinnabar, rifes with lefs 
 heat ; and is, by that means, feparated from it, 
 As the butter of antimony is, therefore, a com- 
 pound of regulus of antimony and fpirit of fait ; 
 the fpirit of nitre being added, which is of fupe- 
 rior attraction, difpofleffes the fpirit of fait of the 
 regulus \ and combines itfelf with it ; and the 
 fpirit of fait, together with any redundant 
 quantity of the fpirit of nitre, is brought over 
 in the diflillation : leaving the regulus of an- 
 timony, and that due proportion of fpirit, 
 which, by its combination, it can fix. This 
 being afterwards exppfed to the heat fufficient 
 for the deflagration of nitre : the fpirit of nitre, 
 combined with the regulus of antimony, de- 
 flagrates with it ; and deftroys the fulphur, till 
 the regulus be reduced to a calx -, in the fame 
 
 pianner. 
 
Chemical Preparations. 279 
 
 manner, as if crude nitre had been ufed in- 
 ftead of the fpirit. 
 
 It being evident, therefore, that, when the 
 fpirit of fait is diftilied off in this procefs, no- 
 thing remains but regulus of antimony and fpirit 
 of nitre ; it refults, that the regulus itfelf, as it 
 would equally well combine with the fpirit of 
 •nitre, would be effectually the fame as the 
 butter ; and that the preparation might, there- 
 fore, be made much cheaper from the regulus, 
 and fpirit of nitre than by the more complex 
 procefs, where the butter is to be previoufly 
 prepared. When, therefore, this medicament 
 is demanded, it may be prepared in the genuine 
 manner by this cheap and eafy method. 
 
 A cheap and eafy method of preparing genuinely 
 the bezoar mineral. 
 
 Take any quantity of the regulus of an- 
 timony prepared by any procefs j and dif- 
 folve it in fpirit of nitre : evaporate the fo- 
 lution to drynefs j and put the remaining 
 matter, in a crucible, and calcine it, in a 
 very ftrong fire, for half an hour, or more, 
 according to the quantity to be calcined. 
 
 Note. 
 
 By this means, any quantity of the Bezoar 
 
 mineral, exadtly the fame with that produced 
 
 by the molt ejobarate procefs, may be very foon 
 
 T 4 mads 
 
280 Chemical Preparations. 
 
 made. But as this is not known to thofe, of 
 whom it is demanded to prepare, or procure 
 this medicine in the wholefale concerns, they 
 moft frequently fubftitute the diaphoretic anti- 
 mony for it ; and if, indeed, they commit no 
 greater fraud than this fubftitution, provided 
 the diaphoretic antimony be carefully prepared, 
 well wafhed, they may be very well ex- 
 ci. . for, undoubtedly, there is no difference 
 betwixt the one and the other ; as neither are 
 any thing but the perfect calx of antimony 5 that 
 is, the earth, which is the bafis of that femime- 
 tal, wholly deprived of thefulphur by deflagra- 
 tion with nitre: in which operation, it is indif- 
 ferent, whether the crude nitre, as in the dia- 
 phoretic antimony, or the fpirit, as in the bezqar 
 mineral, be employed. 
 
 JEthiops ' antimonialis. 
 
 Flux equal quantities of antimony, and 
 fee fait, together, in a crucible, for an 
 hour : then let the matter cool : break the 
 crucible ; and feparate the fcoria : after- 
 wards rub the regulus, thus obtained, with 
 an equal quality of quickfilver, till they bp 
 incorporated. 
 
 Note. 
 
 This was a fecret, by which, at one time, the 
 greatefl: wonders in medicine were pretended 
 to be done. It has been, fince, laid open \o 
 
 the 
 
Chemical Preparations. 281 
 
 the public ; and recommended, as a preparation 
 of the higheft importance : but, I believe, on 
 examination, it will be found to have no fur- 
 ther efficacy in it, than what belongs to the 
 aethiops mineralis, prepared from common ful- 
 phur. For it may be much doubted, notwith- 
 finding the antimony is here after the fluxing 
 with fait, called by the name of regulus, whether 
 any change be at all made in it by that operation ; 
 and, whether, confequently, the crude anti- 
 mony, ufed without any fuch previous prepara- 
 tion, may not be equally well ufed for this pur- 
 pofe : indeed, if there is a great ground of pre- 
 fumption, that the antimony really undergoes 
 any alteration, by fluxiijgit thus, it mufl render 
 the medicine very exceptionable ; as in all ap^ 
 proaches towards the reguline ftate, the anti- 
 mony acquires fuch active powers, that fcarcely 
 any caution in the adminiftering it, is fufficient 
 to countervail the hazard of its violent opera- 
 tion. 
 
 Kermes mineral^ or poudre des chartrenx. 
 
 Take, of antimony, four pounds, of fo- 
 lution of fixt nitre perdeliquium, one pound, 
 of rain water, three pounds : boil them two 
 hours -, and then filter the boiling decoc- 
 tion, through paper : let it then Hand, at 
 reft, twenty four hours 3 and it will let fall 
 a yellowifh or faffron coloured powder, the 
 
 fluid 
 
282 Chemical Preparations. 
 fluid becoming dear. This fluid, being then 
 poured off by inclination, the powder muft 
 be wafhed, by repeated affufions of warm 
 water ; and, four ounces of fpirit of wine 
 being burnt upon it, afterwards dried, and 
 kept for ufe. 
 
 Note. 
 
 The antimony ought to be extremely well 
 powdered for this preparation \ as the produce 
 will greatly depend upon the finenefs of it. 
 
 The ufe of fixt nitre, preferably to any other 
 pure fixt alkaline fait, is without any reafon : 
 and foap lees will facilitate the extraction of 
 the fulphur from the antimony more than a 
 meer folution of fixt alkaline fait. 
 
 The burning fpirit of wine upon the ful- 
 phur, thus extracted, is of no effect : for tho' 
 it was ignorantly praftifed, as the means of 
 edulcorating moft of the antimonial and mer- 
 curial preparations, by the former chemifts •> 
 yet, whoever confiders, that it is only the va- 
 pour of fpirit of wine that burns, and that the 
 body of it, which is commixt with the kermes 
 mineral, or any other matter, under operation, 
 is only flightly heated, muft be fenfible of the 
 abfurdtty of it. 
 
 The fame folution of alkaline falts, which 
 was at firft ufed, may, after the fulphur has 
 precipitated from it, on its growing cold, be 
 equally well ufed again as any freflh quantity; 
 
 for 
 
Chemical Preparations. 283 
 
 for it is only through the diminution of the 
 power of the menffcruum, by the abatement 
 of the heat, that the precipitation is made : 
 and it will, therefore, diflblve, and take up, 
 the fame quantity again, when heated to the 
 fame degree ; arid may ferve any repeated 
 number of times, if water be added, to al- 
 low for the evaporation, and maintain the pro- 
 per quantity of fluid. 
 
 The folution of fait fhould, likewife, be 
 poured back again, on the fame quantity of 
 antimony, and the boiling, and other fubfe- 
 quent treatment renewed 3 for it will be found 
 to yield a confiderable quantity of the fulphur, 
 notwithftanding the firft taken from it : and 
 this may be with advantage even the third 
 time. 
 
 The moft profitable manner, therefore, of 
 preparing the kermes mineral, will be found 
 to be the following. 
 
 Moft profitable manner of preparing the kermes 
 mineral. 
 
 Take, of antimony, four pounds j and, 
 having reduced it to a fine powder, put it 
 into a folution of one pound of any fixt 
 alkaline fait, diffolved in three pints of wai- 
 ter • or into three pints of foap lees j boil 
 the mixture half an hour 5 and then filter the 
 folution through paper, by means of two or 
 
 three 
 
284 Chemical Preparations. 
 three fmall earthen cullenders ; that it may 
 not grow cold before it run through : let 
 the filtered folution ft and for twenty four 
 hours \ and, then, pour off the clear fluid, 
 from the fedimentj and, putting it to the 
 fame powdered antimony it was before 
 boiled with, repeat the former treatment ; 
 and do the fame a third time, if the quan- 
 tity of fulphur, obtained the fecond, give 
 encouragement for it : the whole quantity 
 of fulphur, being, then, put together, the 
 fluid rauft be drained off from it, in a filter; 
 a linnen cloth being put over the paper : 
 and the fulphur muft be afterwards dried, 
 on a chalk-ftone, in the fhade. 
 
 The folution of fixt alkaline fait, or the 
 foap lees, which ever were ufed, may be kept 
 to be employed for the fame purpofe, ano- 
 ther time; or a further precipitation may be 
 made from it, of the fulphur, by dropping 
 fpirit of fait into it, fo long as any turbid- 
 nefs, or effervefcence fhall appear : but, if 
 the repeating the boiling and precipita- 
 tion be neglected, according to the firft 
 procefs: more than half the kermes mi- 
 neral, 
 
Chemical Preparations. 285 
 neral, that may be produced, would be 
 
 loft. 
 
 Note. 
 
 By thefe means, the kermes mineral may be 
 prepared very eafily in any quantity : and, as 
 it is, in fad:, the fame with the fulphur aura- 
 turn antimonij, they may be promifcuoufly 
 ufed ; or rather this method of making the 
 fulphur auratum may be fubftituted for the 
 other ; as the antimony, after the extraftion 
 of the fulphur, in this manner, will equally 
 w T ell, or even better, ferve for the making the 
 martial regulus, than while it is in its more 
 crude ftate. 
 
 Fever powder. 
 
 Take crude antimony and calcine it with 
 animal oil for two hours 3 then put it into 
 nitre, melted in a crucible ; and let it con- 
 tinue there for fome time 5 and afterwards 
 take out the matter, and wafh the falts 
 from it, and dry it. 
 
 Take, alfo, quidkfilver : diftill it three 
 times, from crude antimony : then diffolve 
 it in fpirit of nitre ; and, having evapo- 
 rated the fluid, calcine the dry mafs, in a 
 crucible, till it turn yellow. 
 
 Note. 
 
286 Chemical Preparations, 
 
 Note. 
 
 This is the procefs for the famous fever 
 powder, as given by the pretended inventor. 
 
 The calcination of- the antimony, with ani- 
 mal oil, is not of the leaft confequence to the 
 preparation ; for, fo long as the antimony is 
 commixt with any inflammable fubftance, ite 
 own calcination will be prevented : and, in- 
 deed, whatever change might have been pro- 
 duced in it, by any more efficacious operation , 
 it would have been intirely fruftratcd again by 
 the deflagration with nitre j which in all cafes 
 brings the antimony to a perfect calx, where 
 nothing remains, but that pure fimple earth, 
 which is the bafis of this femimetal ; and does 
 not appear to have the leaft operation on the 
 human body, nor can ever fuffer any change 
 in its nature while pure. 
 
 The abfurdity of diftilling the quickfilver 
 from antimony is equally great : for no ana- 
 lyfis of the antimony can be made by means 
 of the addition of quickfilver alone ; and, there- 
 fore, nothing can be imparted to the quickfilver 
 from it ; nor any other effects produced, than 
 what the diftillation alone may caufe. 
 
 If we take away thefe inefficacious parts of 
 the procefs, and examine the other opera tions? 
 we fhall fee, that the antimony is converted 
 into the ftate, where it is called the diaphore- 
 tic ; and by the fame diredfc means ; and the 
 quickfilver, into the red precipitate, imperfed:ly 
 calcined : which two preparations, confequent- 
 
Chemical Preparations. 287 
 
 ly, compofe this boafted remedy. In what 
 proportion, thefe are commixt, to form the 
 powder, has not been hitherto revealed by the 
 preparer of it ; nor, perhaps, abfolutely fettled 
 in his own practice 5 but, from the manner of 
 operation, one may well prefume, that the 
 mercurial part is fmall, compared to the anti- 
 monial 5 as, otherwife, more frequent evacua- 
 tions, or other fenfible eflfe&s, would occur on 
 its being taken. 
 
 Preparation of the Greek 'water (for the [ela- 
 tion of fiver, for the converting red, or light 
 coloured hair, into a deep brown.) 
 
 Take any quantity of filver filings, and dif- 
 folve them in fpirit of nitre, proved or puri- 
 fied according to the dire£tions given p. 174 • 
 the fpirit of nitre, and the filver, being put 
 in a mattrafs, mull be placed, firft, in a 
 gentle fand-heat, and afterwards removed 
 where the fluid may be made to boil for a 
 fhort time : being taken out of the fand- 
 heat while yet hot, add as much water as 
 may have evaporated during the boiling.; 
 and, when the folution is grown cold, de- 
 cant off the clear fluid from the fediment, 
 if there be any, and the undifTolved part of 
 the filver filings \ which may be diflblved, 
 
 likewife, 
 
288 Chemical Preparations. 
 
 like wife, by adding more.fpirit of nitre, and 
 
 repeating the fame treatment* 
 
 Note. 
 
 The folution of filver, thus obtained, is the 
 Greek water, ufed for turning red, or light co- 
 loured hair to brown. Its efficacy may be 
 greatly improved by wafliing the hair, before 
 the application of the water, with common 
 water, in which fome fait of tartar, or any 
 other fixt fait has been diflblved ; the propor- 
 tion may be an ounce and half of the fait of 
 tartar, to a pint of the water. 
 
 Lunar caajlic* 
 
 Diflblve pure filver, in about twice its 
 weight of aqua fortis, in a fand-heat : 
 then, the heat being increafed, evaporate to 
 drynefs : afterwards melt the matter, in & 
 crucible, that it may be poured into pro- 
 per molds ; carefully avoiding too great 
 heat, left it grow thick, beyond the juffc 
 degree. 
 
 Note. 
 
 The college of London, in this proeefs, nave 
 
 done very improperly, in directing aqua fortis 
 
 inftead of fpirit of nitre : for the aqua fortis, 
 
 containing a proportion of oil of vitriol, will 
 
 I fail 
 
Chemical Preparations. 289 
 
 fail to make a perfect folution of the fiiver ; of 
 which a part, therefore, will be corroded only. 
 The college of Edinburg have avoided this 
 miftake ; but have fallen into a greater, in or- 
 dering the fufion to be continued, fo long as 
 the matter fhall emit any fumes : by which 
 circumftance, they deftroy, in a great degree, 
 the efficacy of this medicament : for its only ufe, 
 being, as a cauftic, and its efcarotic quality, de- 
 pending on the concentrated acid of the fpirit 
 of nitre, if that acid be thus expelled, a pro- 
 portionable diminution of its ftrength rnuft, 
 confequently, accrue. The manner of pre- 
 paring the lunar cauftic, fhould be, therefore, 
 as follows. 
 
 Beji method of preparing the lunar cauftic. 
 
 Take, of fiiver filings, any quantity : put 
 them, in a fmall glafs body, with three times 
 their weight of fpirit of nitre, purified ac- 
 cording to the direftions given p. 174 : let 
 the body remain without heat, till the fpirit 
 of nitre appear no longer to aft on the fii- 
 ver ; and then place it in a moderate heat, 
 till all the fiiver be diffolved : after which, 
 fir ft evaporate away the moifture, and then 
 put the dry mafs into a crucible - y and give 
 it a heat juft fufficient, to make it run into 
 
 U fufion : 
 
290 Chemical Preparations. 
 fufion : as foon as it is melted, pour the 
 matter into proper formed iron molds, 
 ilightly greafed. 
 
 Salt of JleeL 
 
 Take, of ftrong fpirit, or oil of vitriol 
 ten ounces, of fteel filings, four ounces, of 
 water, two pints : mix them - y and, the 
 efFervefcence being over, let the mixture 
 ftand, for fome time, in hot fand : then 
 pour off the fluid , and filter it through 
 paper 3 and, after the neceflary evaporation, 
 fet it to chryftallize. 
 
 Note. 
 
 This procefs of the college is at prefent 
 feldom obferved : for, as this is only an artifi- 
 cial preparation of green vitriol, exadly the 
 fame with the natural, the latter is fubfiituted 
 in the place of it ; but fhould be firft purified, 
 and treated in the following manner* 
 
 Method of converting the common green vitriol 
 i?ito fait of Jieely equally good 'with that pre- 
 pared by the regular procefs. 
 
 Take, of common green vitriol, any 
 quantity : dhTolve it in four times its weight 
 
 of 
 
Chemical Preparations. zgi 
 of boiling water ; filter the folution, thro' 
 paper; and add, to it, oil of vitriol, in 
 the proportion of two drams to every 
 ounce : let it then Hand to chryflallize ; 
 and, when the chryftals are formed, take 
 them out, and dry them, in the fhade. 
 
 Note. 
 
 This will equal, in all refpefts, the fait of 
 fteel prepared by any other procefs : as the ad- 
 ditional oil of vitriol will prevent its growing 
 turbid, and brown, by keeping ; and it may* 
 therefore, be allowably fubftituted for the kind 
 regularly prepared. 
 
 Ens veneris, Gr flowers of JieeL 
 
 Take, of wafhed colcothar of green vi- 
 triol, or of fteel filings, one pound, of fal 
 ammoniacum, two pounds : mix, and fub- 
 limethem, in a retort ; and re-commix what 
 remains in the bottom of the retort with the 
 flowers, by pounding them together : repeat 
 the fublimation, till the flowers acquire a 
 beautiful yellow colour : to what remains 
 after the laft fublimation, half a pound of 
 fal ammoniacum may be added -, and the 
 
 U 2 mixture 
 
292 Chemical Preparations. 
 mixture fublimed as the other ; and this 
 method may be repeated, as long as the 
 flowers can be obtained of a good colour. 
 
 Note. 
 
 A difficulty feems to be fuppofed, in this 
 procefs of the college of London, of obtaining 
 good coloured flowers at the firft fublimatien : 
 but it is very eafy to do it, if proper methods be 
 perilled ; and with a much lefs quantity of 
 fteel, or colcothar, than is here prefcribed ; tho' 
 the cheapnefs of thofe ingredients renders it, 
 indeed, a matter of indifference, what quantity 
 is ufed. But the college have been extremely 
 careful to make up for the redundance, at firft 
 ufed, by directing, that fubfequent fublimati- 
 ons to produce half a pound, or lefs, of the 
 flowers, each time, fhould be made ; that none 
 of the colcother, or filings, may be wafted; not 
 confidering, that every fuch operation would 
 coft, befides the trouble, twenty times as much, 
 as the value of the filings, or colcothar, faved. 
 
 The college of Edinburg make the ens 
 veneris, and flowers of fteel, to be different pre- 
 parations j and dired: the colcothar of blue vi- 
 triol to be ufed for the firft : but where yel- 
 yel flowers can be prepared from the blue 
 vitriol, (for it cannot be done with all parcels 
 of it,) it muft undoubtedly be from the iron 
 contained in it -, and they are, therefore, the 
 fame as thofe prepared from green vitriol, or 
 
 crude 
 
Chemical Preparations. 293 
 
 crude iron : for which reafon, wherever ens 
 veneris is ordered, the flowers of fteel, pre- 
 pared as above, is the kind fupplied : and 
 they may be obtained perfedt, with greater 
 certainty, by one fublimation, if the following 
 method be ufed, than the college feem to 
 think practicable, by their advifing repeated 
 fublimations for raifing a proper colour. 
 
 Improved method of making the ens veneris, or 
 fowers of fteel. 
 
 Take, of green vitriol, one pound : dif- 
 folve it in two quarts of warm water ; and 
 precipitate the other from it, by adding 
 to this folution, half a pound of pearl- 
 afhes, diflblved in water : pour off the 
 fluid, when the fediment has fubfided ; and 
 add frefh quantities of water, once or 
 twice, to wafh the falts from the precipi- 
 tated powder -, which muft afterwards have 
 the remaining fluid drained from it in a 
 filter^ and then be dried. 
 
 Let fix pounds of fal ammoniacum be 
 then powdered ; the foul parts being fcraped 
 off, or picked out ; and afterwards well 
 mixed with the oker, or precipitated iron, 
 prepared as above : put them into a retort, 
 
 U 3 with 
 
294 Chemical Preparations. 
 with a very wide fhort neck ; and add, to 
 them, two ounces of fpirit of fait : fit on a 
 very large receiver -, and fuhlime the flowers ; 
 gradually fuppreffing the fire, when nearly 
 the^whole is raifed. If the neck appear to 
 be choaked by the flowers, as muft be con- 
 cluded from the receiver's feeming unduly 
 cold, the receiver muft be taken off \ and a 
 paflage procured, by opening a way, thro* 
 the flowers in the neck, by a flick. 
 
 Note. 
 
 The precipitated oker of the vitriol may be 
 prepared in a larger quantity ; and kept ready 
 for this ufe : and, if that be done, flowers of 
 fteel may, by this method, be prepared, with 
 great certainty ; and very little trouble, of the 
 moft full and bright yellow colour ; if the fire 
 be not too long continued : and what remains 
 in the retort, or is found difcoloured in the neck, 
 may be ufed for making the volatile fpirit of fal 
 ammoniacum; for which purpofe, it will be no 
 way damaged by the treatment of it in this pro- 
 cefs : or this caput mortuum, and other foul 
 parts, may be expofed to the air to deliquate, 
 as the London college advife, in order to make 
 the deliquated fteel, which is the fluid that 
 will run from it. 
 
 It is not an eafy matter to adulterate the 
 flowers of fteel without deflroying the bright 
 
 colour ; 
 
Chemical Preparations. 265 
 
 colour : for there is no fubftance of the fame 
 teint, that would not be equally dear : and if 
 cerufs calcined yellow, or yellow oker, be ufed, 
 they will greatly diminifh the vividnefs of the 
 colour ; (o that, if any fo fophifticated be com- 
 pared with a fpecimen of fuch as is perfedly 
 good, the difference will be eafily perceived. 
 But a more certain proof of any fuch adultera- 
 tion may be quickly made, by putting the 
 flowers into a crucible, and giving a fubliming 
 heat ; which will diflipate them, leaving the 
 cerufs, oker, or any fuch matter, alone in the 
 crucible. 
 
 Aurum mofaicam. 
 
 Take, of tin, one pound, of flowers of 
 fulphur, feven ounces, of fal ammoniacum, 
 and of purified quickfilver, each half a 
 pound : melt the tin 5 and add the quick- 
 filver to it : when the mixture is become 
 cold, powder it ; and mix it, intimately, 
 with the fal ammoniacum, and fulphur : 
 then fublime them in a mattrafs : the au- 
 rum mofaicum will be found under the 
 fublimed mafs, with fome drofs, at the bot- 
 tom of the mattrafs. 
 
 Note. 
 
 The proportion of quickfilver, and fal'ammo- 
 niacum alfo, are in this procefs of the college, 
 
 U 4 left, 
 
296 Chemical Preparations. 
 
 lefs, by one half, than in thofe of the Edinburg 
 pharmacopeia, and other books : but, being fuf- 
 ficient to anfwer the end, this diminution is a 
 real improvement of the preparation ; as con- 
 fiderably leflening the expence. 
 
 The conduct of this procefs is fomewhat cri- 
 tical ; for it very often mifcarries; at leaft, with 
 refpeft to the quantity of the perfeft produce : 
 as, frequently, only a fmall part of the cake is 
 found of the due colour and brightnefs. 
 
 In order, therefore, to avoid the caufes of 
 this failure, it is beft: to fcrape off, and pick out 
 all foul parts of the fal ammoniacum ; and to 
 take care, that the tin, and quickfilver, parti- 
 cularly the latter, be not adulterated with lead. 
 
 The calcination is beft performed in a coated 
 glafs body, in the naked fire : for there is no 
 certainty, in a fand heat, of raifing the cinna- 
 bar formed by the quickfilver, intirely from the 
 tirj v without a longer continuance of the heat, 
 than is confiftent with the fuccefs of the opera- 
 tion, in the main point. The coated body 
 ihould be of a very long form ; and little more 
 of it fliould be expofed to the heat, in the ca- 
 vity of the furnace, than the part containing 
 the materials. By having a great part of the 
 body out of the heat, the whole of the fal 
 ammoniacum, and quickfilver, may be pre- 
 ferved \ as the fal ammoniacum will be col- 
 lected with part of the fulphur near the top of 
 it, and the quickfilver with the other part of 
 the fulj-tiur, combined in the form of cinna- 
 bar, nearer to where it is expofed to the fire : 
 2 the 
 
Chemical Preparations, 297 
 
 the fal ammoniacum, thus faved, may be ufed 
 for making the volatile ipirit ; for which pur- 
 pofe, the fulphur commixt with it will no way 
 injure it : and the quickfilver converted into 
 cinnabar may be, with any other quantities of 
 foul cinnabar, or calomel, revived by distilla- 
 tion with quick- lime and pearl-aihes 5 and, 
 by this means, the principal expence in making 
 the aurum mofaicum re-imburfed. 
 
 Flowers of bifmuth. 
 
 Take any quantity of bifmuth, or tin 
 glafs : reduce it to a fine powder ; and 
 mix it thoroughly with double its weight 
 of nitre powdered alfo : put the mixture, 
 by half a fpoonful at a time, into an 
 earthen body perforated in the fide and 
 furnifhed with allodials, when the body is 
 red-hot : the operation being over, take off 
 the allodials ; and colle£t the flowers •> which 
 will be found in them, by fweeping them 
 out with a feather. 
 
 Note. 
 
 This is the beft procefs, which has been hi- 
 therto given, for the flowers of bifmuth ; and 
 is much preferable to Lemery's method of 
 ufing a previous calcination, like that of lead, 
 
 and 
 
298 Chemical Preparations." 
 and fubliming the flowers with fal ammonia- 
 cum inftead of nitre. This may be yet, how- 
 ever, rendered more fafe, and eafy ; if the 
 earthen veffel, inftead of the form of a body 
 or cucurbit, be. made in that of a retort, and 
 tubulated in the bend of the neck, direftly 
 over the center of the bottom. The tube 
 fhould be about an inch and a half high, and 
 of about an' inch diameter ; and through the 
 orifice which this tube affords, the matter may 
 be much better thrown in, out of a proper 
 fpoon, than through the hole in the fide, as 
 dire6ted in the above procefs -, that cannot be 
 clofedby any convenient means ; but will fuf- 
 fer the fumes of the bifmuth to break out r 
 which muft be avoided, both on account of the 
 lofs of the flowers, and the nufance it gives to 
 the operator. The tube, in the earthen retort, 
 ihould have an earthen ftopper made along 
 with it ; which fhould be put into the hole, 
 as foon as poflible, after the matter is thrown 
 in. The neck of the earthen retort fhould 
 be three inches wide in the narroweft part : 
 inftead of the allodials, a large receiver fhould 
 be ufed ; which will anfwer the end better, 
 and with much lefs trouble : in this receiver 
 ihould be made a fmall hole, for a vent to the 
 air generated in the explofion of the nitre with 
 the fulphur of the bifmuth ; for otherwife the 
 receiver will be very liable to be thrown off 
 from the neck: nor fhould the junfture of the 
 receiver with the retort be made tco clofe or 
 firm with lute for the fame reafen. 
 
 2 It 
 
Chemical Preparations. 299 
 
 It is proper to put about an inch height of 
 fend, in the earthen body, or retort ; in order 
 to prevent the matter falling on the heated 
 bottom of the veffel, and caufing it to crack : 
 which will be generally the confequence, if 
 this precaution be not ufed. 
 
 The flowers of bifmuth have, at prefent, no 
 place in medicine ; but they are greatly ufed 
 as a dry cofmetic, or rather fucus ; giving a 
 fairnefs, and clear appearance, to thefkin, when 
 rubbed on it. It is the general pra&ice of the 
 ladies, in Spain, and Portugal, to employ this 
 fubftance, as a dry paint on their faces and 
 neck; and a perfon in London, who pre- 
 pared it to be fent there is fuppofed to 
 have got fome thoufand pounds by the con- 
 cern : it is now, alfo, coming into fre- 
 quent ufe here, in the fame way ; and will 
 probably be much more generally introduced 
 than at prefent. As, therefore, the prepara- 
 tion called the magiftery of bifmuth will an- 
 fwer the fame purpofe ; and may be prepared 
 with much lefs trouble, I will fubjoin the bed 
 manner of preparing that alfo. 
 
 Magi fiery of bifmuth. 
 
 Take four pounds of pure fpirit of ni- 
 tre 5 put it into a mattrafs • and add, to it, 
 as much bifmuth powdered, as the fpirit 
 will diffolve 3 which will be, according to its 
 
 ftrength, 
 
300 Chemical Preparations. 
 ftrength, about eight or ten ounces - y preci- 
 pitate, then, the bifmuth from the folution, 
 by putting to it, gradually, four pounds of 
 pearl-afhes, diffolved in three quarts of 
 water, and ; filtered through paper : when 
 the precipitated powder has fubfided, pour 
 off the clear water ; and add feveral fuc- 
 ceffive quantities of frefh, to wafh away all 
 the falts : the powder muft then be freed 
 from the remainder of the fluid, by drain- 
 ing through a filter of paper, with a linnen 
 cloth laid over it : and afterwards dried on a 
 chalk-ftone in the {hade. 
 
 Note. 
 
 This precipitation has been ordered to be 
 made with fea fait, inftead of fixt alkaline fait: 
 but that is by no means a proper, (though 
 cheaper) method, where the magiftery is in- 
 tended to be ufed as a cofmetic : for, in that 
 cafe, the acid, remaining conjoined with the 
 bifmuth, would render it much too acrid for the 
 fkin : nor can it then be ftriftly deemed a ma- 
 giftery 5 which fuppofes the precipitation to be 
 made by feparating the acid difiblvent. But 
 when it is prepared as above, if the falts be in- 
 tirely waihed out, it is as gentle as the flowers 
 made by the above procefs ; and may be 
 fubftituted for them, for this purpofe of a fu- 
 
 cus, 
 
Chemical Preparations. 301 
 
 cus, though it is not abfolutely the fame thing : 
 this being in fa& the bifmuth itfelf, unchanged 
 any other way, than by reducing it to the moft 
 impalpable powder ; and the flowers of the 
 bifmuth reduced to a calx, containing only 
 that earth, which is the bafis of this femime- 
 tal ; the fulphur being deftroyed by the defla- 
 gration with the nitre. 
 
 The flowers, or magiftery of bifmuth, are 
 very liable to be adulterated by chalk, lime, or 
 white lead : ail which render it injurious, when 
 ufed conftantly as a dry fucus : and it is very 
 difficult to furnifh a Ample method of detect- 
 ing the abufe. If, however, the flowers ap- 
 pear lighter than a proper fpecimen, they may 
 be, with certainty, concluded to be adulterated 
 with chalk, or fome calcarious earth : and if 
 it be fufpefted, they are fophifticated even 
 where of due weight, the putting fome of the 
 flowers into a crucible, with the fame bulk of 
 charcoal duft thoroughly mixt with them, will 
 fliew, if white lead, or calcined tin, be com- 
 mixed with them, by reducing thofe metals to 
 their metallic ftate - y in which they will be 
 found in the bottom of the crucible. But this 
 trial will not avail in the cafe of the magiftery ; 
 for the bifmuth, not having been analyzed in 
 the preparation, will itfelf be fufed -, and com- 
 bine with the lead, or tin, in one equal metal- 
 lic body. 
 
 Diflilled 
 
302 Chemical Preparations, 
 
 Dijtilkd verdigrife \ properly ^ chryjlals of 
 verdigrife. 
 
 Take, of the bell: verdigrife, four ounces, 
 and of diftilled vinegar, one quart : the 
 verdigrife being well powdered, put them 
 together into a mattrafs, with a fmaller one 
 inverted into the neck of it ; and place it 
 into a gentle fand-heat ; where it muft re- 
 main, being fometimes fliaken, till the vine- 
 gar has diffolved as much as it can of the 
 verdigrife. Put it, then, into a proper 
 glafs for the decanting the clear fluid frofri 
 the fediment ; and, when it has ftood a due 
 time to fettle, let the fluid part be carefully 
 poured off; and evaporated to about one 
 third. It muft then be fet to fhoot in a 
 receiver with a wide neck -> and, when the 
 chryftals are formed, they muft be taken 
 out, and carefully dried. 
 
 A frefh proportion of vinegar may be 
 added to the part of the verdigrife, which 
 the firft quantity left undiflblved ; and the 
 mothers, or fluid, remaining after the chry- 
 ftals were formed; may be put to it ; and the 
 
 other 
 
Chemical Preparations. 303 
 other parts of the procefs repeated as be- 
 fore : by which means, a fecond quantity of 
 chryftals will be obtained. 
 
 Note. 
 
 The verdigrife, ufed for this purpofe, fhould 
 be chofen by its green colour, and tranfparency : 
 for, where it happens to be dried to a greyifh 
 blue powder, it will require a greater propor- 
 tion of vinegar to form it into chryftals. 
 
 The diftilled vinegar produces the moft beau- 
 tiful chryftals : but common vinegar is more 
 frequently ufed by thofe, who prepare them ; 
 as it is much cheaper, and will afford very 
 good coloured chryftals, if care be taken,, iu 
 the evaporation, not to fuffer any part of it to 
 burn to the glafs. 
 
 This preparation is feldom ufed in medicine : 
 but is of great value in fome kinds of painting ; 
 as it will, when worked in varnifh, retain its 
 beautiful green colour • which far furpafles that 
 of any other pigment : the great demand there 
 is at prefent for this fubftance* on account of its 
 being ufed for painting coaches according to the 
 new tafte, makes it well worth the notice of 
 thofe, who are concerned in other chemical 
 articles, to endeavour to prepare this in per- 
 fection. 
 
 FiSlitious 
 
304 Chemical Preparations. 
 
 FiSiitious Roman vitriol. 
 
 Take twelve pints of water .; and drop, 
 gradually, into it, five pounds of oil of vi- 
 triol, to which has been added half a pound 
 of fpirit of nitre : put the whole into a large 
 glafs receiver ; and add, to it, fix pounds of 
 copper, or brafs, in filings, or thin plates : 
 let it reihain cold till the more violent effer- 
 vefcence, which will at firft appear, be a- 
 bated, and, then, place it on a fand-heat, 
 which may be increafed, occafionally, till 
 the acid fpirit appear to be faturated with 
 the copper : let the fluid, then, ftand at 
 reft, till it become clear : when pour it care- 
 fully off from the feces 3 and add fome wa- 
 ter to them, to bring off the remaining part 
 of the folution, or to diffolve any chryftals 
 of the vitriol that may be fhot : decanting 
 off this wafhing in a lefs veflel, and of a 
 more proper form than the receiver. Add 
 this to the firft fluid, and evaporate away 
 half the quantity in a leaden boiler; and 
 then fet the remainder in a large receiver to 
 fhoot into chryftals, the chryftals being 
 
 formed 
 
Chemical Preparations. 30^ 
 formed and taken out, keep the mothers, 
 or remaining fluid* to be added to a freflt 
 quantity of the folution, in order to its 
 affording the fait yet diffolved in it -, or, if 
 the whole be done for experiment, or on 
 fome particular occafion, the evaporation 
 and cryflallization may be repeated, till the 
 whole quantity of the fait be obtained in 
 chryftals. 
 
 The fluid being drained from the chry- 
 flals, when they are taken out, in art 
 earthen cullender, the fait fhould be laid to 
 dry in the fhade ; taking care, that no 
 heat approach it 3 which, otherwife > would 
 calcine the chryftals, and hurt their tranf- 
 parency and beauty* 
 
 Note. 
 
 Th& Roniaft, or blue vitriol, is in many 
 places found naturally produced : but not fa 
 copioufly as to take away the neceffity of pre j 
 paring it by art ; efpecially, where refufe cop- 
 per, fuch as the filings and fweepirig of fhops* 
 can be had in fufficient quantity, and the oil of 
 vitriol can be obtained at the prefent low price i 
 this manufacture, indeed, fhould be, as it is 
 at prefent ini pne inftance, joined to that of the 
 oil of vitriol itfeif ; as the unre<ftified fpirit 
 
 X from 
 
306 Chemical Preparations. 
 
 from the fulphur may be employed in it $ 
 
 which makes a faving in the whole procefs. 
 
 The foreign Roman vitriol is not, in general, 
 purely the fait of copper, but fophifticated ei- 
 ther by nature, or art, with another body : but 
 I fhall avoid being more explicit on that point; 
 left it give the hint to thofe, who prepare it 
 here, to avail themfelves of the knowledge of it, 
 inftead of continuing to make it pure, from the 
 want of commodious means to do otherwife. 
 
 Excepting by this method, there is no dan- 
 ger of impofition in the Roman vitriol -, pro- 
 vided care be taken only to accept of none, but 
 what fhall be in chryftals of a large, or moderate 
 fize, and of a full deep bright blue colour. 
 
 SECTION V. 
 
 Of dijlilled waters and fpirits^ either 
 
 not ge7terally known \ or to be made by 
 
 cheaper or more compendious methods 
 
 than are direEled i?i the regular pre- 
 
 fcriptions for them. 
 
 Si??2ple cinnamon water. 
 
 Take of cinnamon one pound, water fuf- 
 ficient to prevent an cmpyreuma, (or burnt 
 flavour) : diftill off one gallon. 
 
 2 Note. 
 
CrtEMicAL Preparations. 307 
 
 Note. 
 
 This water is moft frequently made by 
 Co&ionj the distillation, inftead of improving 
 it, making fuch a feparation of the ethereal oil 
 from the more foluble fubftances contained in 
 the cinnamon, as renders it more incapable of 
 remaining united with the water, without the 
 aid of fome other medium. 
 
 The limple cinnamon water, therefore, not- 
 withftanding diftillation is ordered in the pro- 
 cefles both of the London and Edinburg col- 
 leges, is much better made in the following 
 manner* 
 
 Simple cinnamon water by codlion. 
 
 Take half a pound of cinnamon powdered 
 grofsly, and one gallon of water : put them 
 into a very large kettle, or a ftill, and keep the 
 fluid only of a fimmering heat ; that as lit- 
 tle vapour may rife as poilible ; when it has 
 thus boiled, in the gentleft manner, a quar-» 
 ter of an hour, return what may be come over 
 into the ftill ; and, being cold, ftrain off the 
 water through flannel •, and, after ftanding, 
 decant off the clear part, if any fediment be 
 found. 
 
 X a It 
 
308 Chemical Preparations. 
 
 It may be prepared in lefs quantity in 
 a mattrafs, with a Jong neck ; having a 
 1 mailer mattrafs inverted to make a circu- 
 lation ; and the operation may be performed 
 in a fand-heat. 
 
 Note. 
 
 By this treatment a ftronger water may be 
 obtained by coition from half a pound of cin- 
 namon, than can be had from a pound by di- 
 ftillation : for, though a pound will undoubt- 
 edly afford double the quantity of oil, yet from 
 want of fome faline, or other faponaceous me- 
 dium, to caufe a combination of the oil and wa- 
 ter, the oil neceflarily feparates from the water, 
 after the diftillation ; and leaves it much lefs 
 ftrongly impregnated, than where a lefs quan- 
 tity is ufed, and the oil is not deprived of the 
 faccharine juice, or other bodies of a faline, or 
 fapid nature, which affift its union with the 
 water, when only a gentle coition is ufed, to 
 extradt it from the ligneous part of the bark. 
 
 The caffia lignea is fometimes ufed for mak- 
 ing fimple cinnamon water, on account of its 
 much lower price than cinnamon : but, if, 
 the water be not made very weak, diftillation 
 muft be ufed: becaufe the caffia imparts a 
 ftrong colour to the water ; which would 
 diftinguifh it from the genuine. 
 
 In all other refpedts the caffia is equally 
 good, for the purpofes of making cinnamon 
 
 water, 
 
Chemical Preparations. 309 
 
 water, with the cinnamon itfelf ; as the oils 
 extracted from both are intirely alike : I am, 
 indeed, fatisfied, upon very good authority, 
 that they are the bark of the lame tree ; and 
 the only difference lies in the choice and pre- 
 paration of it, with refped: to the age of the 
 parts it is taken from, and the manner of 
 curing it. 
 
 Spirituous cinnamon water. 
 
 Take, of cinnamon, one pound, of proof 
 fpirit, one gallon, of water fufficient to pre- 
 vent an erapyreuma : one gallon may be 
 diftilled off. 
 
 Note. 
 
 As the expence of cinnamon, in the pro- 
 portion of one pound to a gallon, renders the 
 preparation of this water very dear, a much 
 cheaper method has been found of preparing 
 it equally good, by fubflituting the caflia in the 
 place of the cinnamon ; and leffening, like- 
 wife, the quantity - 7 the common cinnamon 
 water is, therefore, prepared thus. 
 
 Method of making cinnamon water at a fmall 
 expence ■, and equal to the beji. 
 
 Take, of thebeft cafTia lignea bruifed, one 
 pound, of melafTes fpirit, two gallons, of wa- 
 
 X 3 ter 
 
jio Chemical Preparations* 
 ter Sufficient to prevent the burning of the 
 materials : diftill off two gallons : to which, 
 when intended to be ufed as a cordial, add 
 one pound of fugar, fuch as is fold at a- 
 bout eight pence per pound. 
 
 Note. 
 
 This quantity is only half the proportion of 
 cinnamon, ordered in the college prefcription 
 above given ; but, if the caflia be good, it will 
 yield as high a flavour as is agreeable to the 
 palate ; a greater quantity of the oil producing 
 a bitternefs, and too great heat- 
 
 The ufe of melaffes fpirit will render this 
 water much more foft and pleafant than it can* 
 be made from the common proof fpirit : which 
 is apt to be foul, and hotter to the mouth. But 
 where the point is to make the expence as fmall 
 aspofiible, common proof fpirit may be ufed. 
 
 Simple fpirit of lavender, commonly lavender 
 water. 
 
 Take, of frefli lavender flowers, a pound 
 and half, of proof fpirit one gallon : diftil, 
 in balneo, till five pints be obtained. 
 
 Note. 
 
 As fuch a quantity of the lavender flowers 
 would make this water expeniive, it is very fre- 
 quent 
 
Chemical Preparations. 3 1 1 
 
 quent to join rofemary tops to them, and to 
 make a much lefs quantity ferve. 
 
 But there is another method of preparing 
 this fpirit more praftifed, than any of thofe 
 where immediate diftillation is ufed ; which is 
 the commixing the foreign oil of lavender with 
 fpirit of wine without diftillation ; and adding, 
 likewife, a quantity of the ipirit of rofemary, 
 to fave the ufing even too much of the oil of 
 lavender, though the foreign oil can be pur- 
 chafed much cheaper than it can poffibly be 
 prepared here. The moft artful mixture of 
 this kind is as follows. 
 
 'Extemporaneous and cheaper fpirit of lavender. 
 
 Take, of the foreign oil of lavender, one 
 ounce, of the oil of rofemary, in which one 
 drop of oil of cinnamon has been put, half 
 an ounce : mix them with a gallon of clean 
 proof fpirit. 
 
 Note. 
 
 This will appear very agreeable and ftrong ; 
 for the oil of rofemary, with a very flight fcent 
 of that of the cinnamon, refembles greatly the 
 lavender. 
 
 As this fpirit, or water, as it is called, is 
 principally prepared to be ufed as a fcent, or 
 perfume, thefe fubftitutions, or fophiftications, 
 are of a very excufable nature ; and, indeed, 
 with refpeft to medicinal purpofes, there is fo 
 
 X 4 great 
 
3 12 Chemical Preparations. 
 
 great an affinity, in the qualities, betwixt the 
 lavender, and the fubftances ufed for adulterat- 
 ing, or counterfeiting it, that, if the proportion 
 of oil be any way joined to the fpirit, it cannot 
 be fhewn, that the medicine is depraved with 
 refpeft to the intention : nor is it material, 
 whether fpirits of this kind are immediately 
 diftilled from the vegetable materials, or pre- 
 pared from the oils already diftilled ; pro- 
 vided the union be perfedl, betwixt the fpirit 
 of wine and the eflential oil ; and that the 
 fpirit of wine be previoufly rectified to a pro- 
 per degree of purity. 
 
 Compound fpirit of lavender. 
 
 Take, of fimple fpirit of lavender, three 
 pints, of fpirit of rofemary, one pint, of cin- 
 namon, and nutmegs, each half an ounce, 
 of red fanders, three drams ; digeft, and 
 filter. 
 
 Note. 
 
 The deiign of the fanders, being only to 
 colour the fpirit, which has been ufually made 
 of a purplifh red colour, the putting them to 
 the ingredients before diftillation, cannot poffi- 
 bly anfwer the end, in any degree ; as no co- 
 lour will rife from them in the diftillation : 
 they fhould, therefore, be infufed in a part of 
 the fpirit, in a flight digefting heat, or without 
 heat, if a confiderable time be given to them ; 
 2 and 
 
Chemical Preparations. 313 
 
 and then, the fpirit being ftrained off from 
 them, fhould be added to the whole quantity. 
 
 The compound fpirit of lavender is, like the 
 fimple, frequently made by an extemporaneous 
 preparation from the oils : and is not, when fo 
 managed, to be diftinguifhed from that, im- 
 mediately diftilled from the vegetables, or from 
 the fpirit diftilled from the oils, by adding 
 fpirit of wine to them. 
 
 The following method of making this comK 
 pound fpirit extemporaneoufly is the beft, I 
 have hitherto met with. 
 
 'Extemporaneous and cheaper method of prepar- 
 ing the compound fpirit of lavender. 
 
 Take, of red fanders, four ounces, of 
 caffia lignea, two ounces, of Jamaica pep- 
 per, one ounce : having broken the caffia, 
 and pepper, to a grofs powder, put them 
 together into a mattrafs with the fanders, 
 with two quarts of fpirit of wine j and fet 
 them to digeft, in a fand heat, fome- 
 times fhaking the mattrafs ; or, if they can 
 be allowed to ftand for a confiderable time, 
 this tincture may be befl made without 
 heat. After the due digeftion, or infufion, 
 let the fpirit be ftrained off through flannel, 
 to be added to a gallon of proof fpirit ; into 
 
 which 
 
3 14 Chemical Preparations.' 
 which, muft be previoufly put, half an 
 ounce of fpirit of lavender, and an ounce 
 of fpirit of rofemary : the whole quantity 
 of fpirit will then be of a clear red colour ; 
 but in order to give it that purplifh full co- 
 lour, which is efteemed beft, a fmall quan- 
 tity of the folution of any fixt alkaline fait 
 muft be added, by a few drops at a time, 
 with fuch intervals, as may admit of the 
 effe£l of each addition's being perceived on 
 the colour of the fpirit before another be 
 made : and by this means the fpirit may be 
 brought to have any degree of colour de- 
 
 Note. 
 
 The extemporaneous compound fpirit of 
 lavender may be prepared, likewife, with the 
 fame proportion of oils, as is correfpondent 
 with the procefs of the college above given ; 
 but this proportion is much more frequently 
 ufed ; as the oil of rofemary is much cheaper 
 than the oil of lavender; and, with the addi- 
 tion of the fpices, this variation in the quan- 
 tities cannot be eafily perceived \ nor in fad:, 
 with refpeft to the medicinal intention, can it 
 be proved to make any material difference. 
 
 As the preparation of this medicine, from 
 the effential oils, inftead of the vegetables them- 
 felves immediately, does not, as we obferved 
 
 before. 
 
Chemical Preparations, 315 
 
 before, render it any way different from the 
 regular procefs, this deviation may be tolerated : 
 and, if there be any objection to it, the pre- 
 parers arefafe from the imputation of having 
 done wrong, if they keep their own fecret 5 for 
 there is no poflibility of diftinguifhing them, 
 
 Hungary water. 
 
 Take, of the frefh tops of rofemary, one 
 pound and a half, of proof fpirit, one 
 gallon : diftill, in balneo, till five pints are 
 obtained. 
 
 Note. 
 
 The cheapnefs of the oil of rofemary, brought 
 from abroad, has occalioned the Hungary water 
 to be prepared in general, like the fpirit of la- 
 vender, from the effential oil. 
 
 As this fpirit is moftly deiigned for external 
 purpofes, where the fcent is the principal quality 
 regarded, it has been ufual to add fome propor- 
 tion of the oil of lavender to it ; there being a 
 much lefs grateful fmell in the rofemary alone, 
 than when combined with the other : but a lefs 
 proportion of the lavender will anfwer the pur- 
 pofe, if a very flight fcent of cinnamon be added 
 to the rofemary ; which gives it, that aromatic 
 fweetnefs, in which, principally, the lavender 
 differs from it. 
 
 The Hungary water may be, therefore, 
 eafily prepared thus, 
 
 Cheap 
 
'316 Chemical Preparations. 
 
 Cheap and extemporaneous method of preparing 
 the Hungary water. 
 
 Take, of the oil of rofemary, in which 
 one drop of oil of cinnamon has been put, 
 one ounce and half, of the oil of lavender, 
 two drams : mix them with ten pints of 
 proof fpirit of wine. 
 
 Note. 
 
 As it is very neceflary, in this, and all the 
 above cafes, where no diftillation is made after 
 the oils are added to the fpirit, to have it very 
 pure, (which is not to be expe&ed from the 
 common proof fpirit,) the kind called the 
 re&ified proof fpirit, muft be, therefore, 
 from the diftillers : but where that cannot be 
 procured, the eafieft method is to lower the 
 rectified fpirit of wine to the proof ftandard j 
 and to ufe it inftead of the other, 
 
 Aqua mirabilis. 
 
 Take, of cinnamon, two ounces, of rind 
 of lemon peels, one ounce, of angelica feeds, 
 leffer cardamoms, and mace, each half an 
 ounce, of cubebs, two drams, of leaves of 
 balm, fix ounces : on thefe ingredients 
 bruifed, pour a gallon of French brandy ; 
 
 and, ' 
 
Chemical Preparations. 317 
 and, having infufed them four days, diftil 
 off one gallon. 
 
 Note* 
 
 As the cubebs, galangals, and angelica feeds* 
 do not yield an effential oil by diftillation, they 
 may be deemed unneceflary ingredients for the 
 making this water : and the place of the ange- 
 lica feeds may be fuppiied by a fmall propor- 
 tion of the leaves. 
 
 The caflia may, likewife, be fubftituted 
 here, as well in the cinnamon water, in the 
 place of the cinnamon , and the quantity in- 
 creafed ; as may, likewife, that of the lemon 
 peel ; for the water will not be rich with the 
 proportion of ingredients here given. This 
 water may be, therefore, more cheaply and 
 efficacioufly prepared in the following manner. 
 
 Method of preparing a more efficacious aqua 
 mirabilis, with lefs expence. 
 
 I Take, of caffia lignea, three ounces, of the 
 rind of lemon peel, two ounces, of thelefler 
 cardamoms, and mace, each half an ounce, 
 of dried leaves of balm, fix ounces, and of 
 the dried leaves of angelica, one ounce : 
 pour upon them one gallon of proof fpirit ; 
 and, having infufed four days, add a fuffik 
 
 cient 
 
3i8 Chemical Preparations. 
 cient quantity of water, to prevent an em- 
 pyreuma j and diftil off one gallon. 
 
 Note. 
 
 The mace and cardamoms might be omitted 
 without impairing, in any material degree, the 
 flavour, or efficacy of the water ; but, where 
 the original form of the medicine is to be ad- 
 hered to, they may be put in. 
 
 tfhe kings honey water. 
 
 Take, of good French brandy, one gallon, 
 of the beft virginian honey and coriander 
 feeds, each one pound, of cloves, one ounce 
 and half, of nutmegs, benjamin, and ftorax, 
 each one ounce, of vanilloes, in number 
 four, and the yellow rind of the peel of 
 three large lemons : bruife the cloves, 
 nutmegs, coriander feed, and benjamin : 
 cut the vanilloes into fmall pieces : and put 
 all together into a cucurbit ; and pour the 
 brandy on them : after they have digefted 
 forty eight hours, diftil off the fpirit into a 
 retort with a gentle heat. 
 
 To one gallon of this water, add of damalk 
 rofe water, and orange flower water, each 
 
 one 
 
Chemical Preparations. 319 
 one pound and a half -> and of mufk, and 
 ambergrife, each five grains ; firft grind the 
 mufk and ambergrife well with fome of 
 the water ; and afterwards put all together 
 into a large mattrafs : fhake them well ; 
 and let them circulate, three days and 
 nights, in a gentle heat ; and then let 
 all cool : filter, and keep the water well 
 ftopt in phials for ufe. 
 
 Note. 
 
 This is the original procefs for the king's 
 honey water, which Wilfon the chemift intro- 
 duced into vogue as a medicine : it has fince 
 continued in ufe ; and is now efteemed ; but, 
 principally, as a perfume ; which end it ele- 
 gantly anfwers. The multiplicity of ingre- 
 dients, many of them infignificant, are now, 
 however, generally retrenched ; and even the 
 honey, the former bafis of the preparation, in- 
 tirely left out of it. As the alterations have 
 been made in this water, by many of the pre- 
 parers, according to their own fancy ; there 
 can be no recipe given for any certain kind as 
 generally ufed; but the following method will, 
 if perfued, produce a water equal to any hi- 
 therto made of this kind. 
 
 Method 
 
J20 Chemical Preparations* 
 
 Method of preparing an odoriferous fpirit of 
 the kind fame with thofe now fold under the 
 name of the king s honey water. 
 
 Take, of coriander feed, and yellow rind 
 of lemon peels, each half a pound, of caraway 
 feeds, four ounces, of cloves half an ounce : 
 bruife the feeds, and cloves ; and put them, 
 with the lemon peel, into a gallon of very 
 clean proof fpirit j and, after having let 
 them infufe for two days, add water fuffi- 
 cient to prevent an empyreuma 3 and diftil 
 off one gallon. 
 
 To the aromatic fpirit, thus obtained, add 
 of damalk rofe water, and orange flower" 
 water, each one pint; and take of mufk, 
 and ambergrife, each fix grains ; and, hav- 
 ing ground them well to a pafte, with fome 
 of fpirit, tie them in a linnen rag ; and 
 infufe them, three or four days in the 
 fpirit, in a gentle heat ; preffing very flightly 
 the rag feveral times during the infufion. 
 
 Note. 
 
 The Jamaica pepper may be fubftituted, in 
 the preparation of this water, inflead of the 
 
 cloves, 
 
Chemical Preparations. 3^1 
 
 cloves, and nutmegs 3 but, as the quantity is 
 but finally the difference faved is not very ma«* 
 terial. An ounce or two of honey may be, 
 like wife, diffolved in part of the orange flower 
 or rofe water •> and being freed from the dregs, 
 may be added to the fpirit; which will impart 
 a perceptible fmell of honey to the whole, in 
 a degree greater than the diftilling the water* 
 from the honey can produce; and this, giving: 
 aflightclamminefsto the fpirit, fixes the fcent, 
 and renders it more permanent than when thd 
 fpirit contains none but volatile ingredients* 
 
 Anhalt water* 
 
 Take, of the beft turpentine, half & 
 pound, of olibanum, one ounce, of aloes- 
 wood, powdered, three drams* of maftickj 
 clove-july flowers, (or rofemary flowers, ) nut* 
 megs, cubebs, or galangals, and cinnamon, 
 each fix drams, of faffron two drams, of 
 fennel feeds, and bay-berries, each half a 
 dram : powder them ; and, adding five 
 pints of fpirit of wine, digeft them, for 
 fix days, with fifteen grains of mufk, in-* 
 clofed in a fmail linnen bag : then diftil 
 flowly, in balneo; and feparate the clear 
 part of what comes over from the turbid. 
 
 Y Note. 
 
322 Chemical Preparations. 
 
 Note. 
 
 Inftead of the crude turpentine, two ounces 
 of the oil may be, with more propriety, ufed. 
 
 The maftick, cubebs, galangal, faffron, fen- 
 nel feeds, and bay-berries, affording either no- 
 thing by diftillation, or what contributes very 
 little, either to the odour or efficacy of the fpirit, 
 may be beft omitted : the fennel feeds, particu- 
 larly, are exceptionable, as depraving the fcent. 
 
 Eau de carme$> or aqua melijfa compojita. 
 
 Take, of the frefh leaves of balm, four 
 ounces, of the yellow rind of frefh lemon 
 peels, two ounces, of nutmegs, and corian- 
 der feed, each one ounce, of cloves, cinna- 
 mon, and the root of angelica, each half 
 an ounce : having bruifed the leaves, and 
 pounded the other ingredients, put them, 
 with a quart of brandy, into a cucurbit ; of 
 which,, flop the mouth ; and fet it in a 
 warm place, to remain there two or three 
 days : add then a pint of fimple balm wa- 
 ter $ and fhake the whole well together : 
 after this diftil guttatim in balneo, till the 
 ingredients be left almofl dry -, and preferve 
 the water, thus obtained, for life* 
 
 Note. 
 
Chemical Preparations. 323 
 
 The angelica root may be omitted ; as it can 
 impart nothing to the water by diftillation. 
 
 In the place of the brandy, redified proof 
 fpirit may be ufed. 
 
 By the fimple balm water muft be under- 
 ftood a fimple water of the balm diftilled with 
 fpirit : for if fuch water were made without 
 fpirit ; and added only to a quart of brandy, 
 or proof fpirit, in this preparation, and the ma- 
 terials diftilled almoft to drynefs, the propor- 
 tion of the aqueous fluid, to the vinous fpirit, 
 would render it fo weak, as not to be capable 
 of fufpending the effential oils of the fpices, 
 and other ingredients. It is, indeed, contrary 
 to art, and abfurd, to ufe both the leaves of 
 balm, and the fimple water of it, in the fame 
 preparation, where a fubfequent diftillation is 
 to be made*, becaufe the augmenting the quan- 
 tity of the leaves, and adding an equivalent 
 proportion of brandy or fpirit of wine, would 
 anfwer the fame end ; but as there is not any 
 water ordered to be ufed, to prevent an empy- 
 reuma, I fuppofe it was found, that with fo 
 large a bulk of the leaves, proportionably to 
 the quantity of fluid, it was imprafticable to 
 avoid their burning. It would be much bet- 
 ter, neverthelefs, to add two more ounces of 
 the leaves of the balm, and a pint of the 
 brandy or proof fpirit, inftead of the pint of 
 fimple balm water ; and, if enough of the 
 fpirit be made at one time to ufe the common 
 ftill, to add alfo a proper proportion of water to 
 prevent the folid ingredients from burning 
 
 Y 2 when 
 
324 Chemical Preparations* 
 
 when the due quantity is come over ; or 
 otherwife to make the diflillation in balneo, if 
 the quantity of the fpirit to be made be fmall : 
 by either of which means, ufed according to 
 the circumftances, an empyreuma may be a- 
 voided with the full proportion of leaves of 
 balm to the whole fpirit. 
 
 Eau c? arquebajfade^ or vulnerary water. 
 
 Take, of the leaves and roots of comfrey, 
 of the leaves of fage, mugwort, and bugle, 
 each four handfuls : of the leaves of betony, 
 fanicle, and ox eye daify, the greater figwort, 
 plantain, agrimony, vervain, wormwood, 
 and fennel, each two handfuls ; faint John's 
 wort, long birthwort, orpine, Paul's betony, 
 the leffer centory, yarrow, tobacco, moufe- 
 ear, mint, and hyffop, each one handful : 
 cut, and bruife them well, in a mortar : 
 then put them into a large earthen-vefTel ; 
 and pour twenty pints of white wine upon 
 them ; and ftir the whole well together : 
 clofe up the vefTel ; and digeft, in a warm 
 dung-hill, or fimilar heat, for twenty days ; 
 then put the whole into an alembic of pew- 
 ter or copper tinned ; and^dLftil off the 
 
 fluid ; 
 
Chemical Preparations. 325 
 fluid ; which, when thus obtained, is the 
 Eau d'arquebufTade ; and muft be preferved 
 in a clofe flopped bottle. 
 
 Eau de luce. 
 
 Take, of the oil of amber, half an ounce, 
 or more, of fpirit of wine dephlegmated 
 with tartar, one or two pounds : put them 
 into a bottle, and let them remain th^re, 
 for fome days ; fhaking them from time to 
 time ; and the fpirit will be thus ftrongly 
 impregnated with the oil. 
 / Take, then, what quantity you pleafe of 
 this impregnated fpirit, or the whole, if 
 you think proper : put it, with an ounce 
 or two of the choicefl amber, finely pow- 
 dered, into a flafk or bottle, and in a few 
 days you will have a very rich tin6lure of 
 amber. Thefe are the previous prepara-* 
 tions for the mixture called TEau de luce 5 
 which is then to be made in the following 
 manner. 
 
 Take, of the ftrongeft fpirit of fal am- 
 
 moniacum, prepared with fait of tartar, one 
 
 ounce, of the ftrong tin&ure of amber, pre- 
 
 Y 3 pared 
 
326 Chemical Preparations. 
 pared as above, two drams, of fpirit of wine 
 dephlegmated with fait of tartar enough to 
 dilute and volatilize the mixture ; that is, 
 when the fpirit and tin6lure are of the full 
 ftrength, five drams ; which, when well 
 mixed, give the genuine Eau de luce. 
 
 Thofe, who defire to have it perfumed, 
 muft mix lavender, or Hungary water, with 
 the other ingredients, inftead of the de- 
 phlegmated fpirit of wine. 
 
 Note. 
 
 This procefs for the Eau de luce is, like moft 
 other of the French recipes for the preparation 
 of lingular medicines, very abfurd and errone- 
 ous. 
 
 With refpeft to the fpirit of wine, it is necef- 
 fary for this purpofe, that it fhould be highly 
 rectified 3 becaufe, otherwife, when it is lowered 
 with the water in the faline fpirit, it will be 
 rendered below proof; and, confequently, not 
 capable of fufpending the oil of amber : but 
 the dephlegmating with fait of tartar is not 
 particularly material any other way than may 
 regard convenience of method, as it does not 
 give it any power of diffolvrng the oil of am- 
 ber not common to any fpirit rectified to equal 
 ftrength. 
 
 The attempt to difTolve the amber, by fpirit 
 of wine impregnated by the oil, is a grofs er- 
 ror ; 
 
Chemical Preparations. 327 
 
 ror: for whoever will make the experiment 
 will find, that not the minuteft quantity of 
 amber will be diflblved by this impregnated 
 fpirit : nor, perhaps, by any other menftruum 
 whatever hitherto known. This part of the 
 procefs is, therefore, wholly needlefs and im- 
 pertinent. 
 
 The volatile fpirit ufed fhould not be very 
 ftrong of the volatile fait : for, otherwife, the 
 greateft part will be immediately feparated ; as , 
 the addition of fpirit of wine has this general 
 efFeft on volatile fpirits, by weakning the wa- 
 ter as a menftruum of the volatile fait. 
 
 The quantity of the volatile fpirit muft be 
 proportioned, therefore, to the ftrength of the 
 fpirit of wine : and muft be lefs than one half, 
 where the ftrongeft fpirit is ufed, otherwife the 
 oil of amber will feparate from the mixture. 
 
 The Eau de luce may be, therefore, better 
 prepared, according to the very principles on 
 which the above procefs is founded, in the 
 following manner. 
 
 More expedite manner of preparing the Eau 
 de luce. 
 
 Take, of the higheft re£Kfied fpirit of 
 wine, either dephlegmated by the addition 
 of fait of tartar, according to the direc- 
 tions given p. 145, or by diftillation, one 
 quart, of oil of amber once re&ified, one 
 Y 4 ounce ; 
 
328 Chemical Preparations. 
 ounce : put them together into a bottle ; 
 and let them Hand fome days, often fhak- 
 ing the bottle : then decant off the fpirit 
 from the oil remaining undiffolved ; and 
 add four ounces of volatile fait of fal am- 
 moniacum diflblved in a pint of water. 
 . If, on the mixture, the oil of amber ap- 
 pear to feparate from the fpirit, which will 
 be feen by a white milky cloudinefs, add 
 highly re6lified fpirit of wine to it gradually, 
 till the whole become clear - y and, if the vo- 
 latile fait appear to feparate, which may be 
 perceived by the production of a great num- 
 ber of very white fhining particles in the 
 fluid, let it fubfide, and pour off the fpirit 
 from what is thus feparated : for it is cer-> 
 tain, from the nature of the reparation it- 
 felf, that a fufficient quantity of the fait 
 remains. 
 
 If it be defired to have the Eau de luce 
 perfumed, a dram of the oil of rofemary 
 or lavender, or a' mixture of both, may be 
 added to the fpirit of wine impregnated 
 with the oil, before the addition of the 
 volatile fpirit to it. 
 
Chemical Preparations. 329 
 
 Note. 
 
 By thus adj lifting the proportion of the in- 
 gredients, according to their real power of acti- 
 on on each other, by which, a combination of 
 them may be made, this preparation may be 
 perfected without the mifcarriages, to which 
 the above procefs is unavoidably liable, from 
 its error with refpedt to the relative quantity of 
 fome of the ingredients, and its uncertainty with 
 regard to others : and it will, notwithftanding 
 the apparent variation, be exa&ly the fame, as 
 it would if the directions of the former pro- 
 cefs were perfued, fo as to produce a due 
 mixture of the fubftances employed. 
 
 It is the praftice in fome (hops of London, 
 to aromatize the fpirit of wine ufed for the 
 Eau de luce ; by diftiliing it previoufly from 
 cinnamon, mace, nutmegs, and other fpices : 
 but this is a variation from the original procefs; 
 and no improvement of the water, either as a 
 medicine, or a perfume. 
 
 PART 
 
PART III. 
 
 Of galenical preparations, where devia- 
 tions are ufually made from the pre- 
 fcriptions of the college ; or where 
 fophiftications are frequently prac- 
 tifed. 
 
 ConfeStio cardiaca. 
 
 TAKE, of frefh rofemary tops, and 
 juniper berries, each one pound, of 
 lefler cardamom feeds, hulked, zedoary, and 
 fafFron, each half a pound : make a tinc- 
 ture of them, in about one gallon and a 
 half of proof fpirit : ftrain off the tinc- 
 ture ; and reduce it, by a gentle heat, nearly 
 to the weight of three pounds and a half; 
 then, adding the following ingredients finely 
 powdered, make them into an eledtuary; 
 of the compound powder of crabs claws, 
 fixteen ounces, of cinnamon, and nutmegs, 
 each two ounces, and of the fineft fugar, 
 two pounds. 
 
 % Note* 
 
332 Galenical Preparations. 
 
 Note. 
 
 This is the confeftio cardiaca of the college 
 of London ; which is ordered to be made in 
 the place of the confedtio Raleighana : how far 
 it is a proper fubftitute, for that laborious pre- 
 paration ; or with what propriety it is com- 
 pofed to anfwer the medicinal intention of its 
 ufe, it is not my bufinefs to inquire here : but 
 as there is an error in the proportion of the 
 ingredients, which renders its confiftence very 
 incommodious, even for prefent ufe, and im- 
 proper with regard to keeping good the me- 
 dicine for any longer fpace of time, it may be 
 no ufelefs part of this work, to point out the 
 defefts of the prefcription, with refpedt to the 
 form of the medicine ; and to fhow where 
 they may be remedied. The principal fault 
 lies in making the quantity of the fluid of the 
 extract far too great, for the proportion of the 
 powders and fugar : for, as the extract gains 
 very little tenacity from the ingredients, which 
 are the fubjedt of it, the powders, finding lit- 
 tle or no vifcidity to fufpended them, necef- 
 farily fink to the bottom ; and, this feparation 
 of the ingredients renders it very difficult* ccn- 
 fequently, to meafure out dofes, which may 
 contain equal proportions of them ; and, what 
 is ftill much worfe, the proportion pf fugar, not 
 being one third of what is found neceiTary, in 
 order to the preventing fermentation in fyrups, 
 (for the quantities directed by the college them- 
 
 Z felves 
 
Galenical Preparations. 333 
 
 felves for fyrup are two pounds of the fugar to 
 one of the fluid; whereas, there is here only two 
 pounds of the fugar to three and a half of the 
 fluid) the medicine is, confequently, fpoiled by 
 its fermenting, as foon as the warmth of the 
 feafon difpofes it to that ftate : and, as it nei- 
 ther can be made in very fmall quantities, nor 
 is of fo frequent ufe, as to render the renewing 
 the flock very often practicable, this quality 
 occafions a very great lofs to thofe, who pre- 
 pare it according to the above prefcription. 
 
 It is neceflary, therefore, to change the con- 
 fidence of this medicine, without altering the 
 proportion of the ingredients ; which might 
 be done by wafling the fluid to one pound : 
 but then every dofe prefcribed would be, ver- 
 tually, almofl: one third greater than it ought, ac- 
 cording to the original form : to avoid which 
 inconvenience, as well as that arifing from a 
 clofe adherence to the prefcription, the moft 
 proper method is to wafte a fmall part of the 
 fluid \ and to add an equivalent proportion of 
 fome other fubftance, which may contribute to 
 infpiflfate the remainder in fuch manner, that 
 the powders may be duly fufpended, and the 
 aptitude to fermentation at the fame time re- 
 moved. This may be affe&ed by gum arabic 
 or ftarch previoufly boiled ; which will produce 
 the defired effefit without interfering in the 
 leaft degree with the efficacy of the medicine. 
 
 The fpirit of wine in the above prefcription 
 is ordered to be evaporated : but that is a need- 
 lefs wafte of it, as well as of the oil raifed from 
 
 the 
 
334 Galenical Preparations. 
 the rofemary ; which, by a proper treatment, 
 would produced fix pints of Hungary water, 
 without the leaft difference to the extract, if 
 the fpirit of wine be divided into two propor- 
 tionable parts, and the rofemary tops diftilled 
 with one part feparately, and the other ingre- 
 dients with the other : nor will that part of the 
 fpirit, diftilled from the juniper berries, &c. be 
 rendered of no value by the admixture of what 
 rifes from thofe ingredients : for it will be con- 
 verted into one of the beft and moft palatable 
 kinds of Geneva, that can be imagined. 
 
 The following method, therefore, of pre- 
 paring the confedtio cardiaca will be found very 
 advantageous ; and productive of a due con- 
 fiftence of the medicine, without in the leaft 
 altering either the proportion or quality of the 
 ingredients. 
 
 More profitable method of preparing the con- 
 feSlio cardiaca ; without the defeBs found 
 in it, when made according to the form of the 
 college. 
 
 Take, of frefh rofemary tops, one pound: 
 add to them fix pints of proof fpirit, and 
 one quart of water, to prevent an empy- 
 reuma : put them into a proper alembic $ 
 and diftill off fix pints. 
 
 Take, 
 
Galenical Preparations; 335 
 Take, alfo, of juniper berries one pound, 
 of the leffer cardamom feeds hufked, zedoary, 
 and faffron, each half a pound : add to 
 them another gallon of proof fpirit ; and, 
 after digefting fome time, put them, alfo, 
 into a proper alembic, with a quart of wa- 
 ter^ and diflill off one gallon. 
 
 Put what remains, after both the diftilla- 
 tions, together into a proper veffel; and 
 evaporate it, till there remain only three 
 pounds $ adding, in the mean time, of gum 
 arabic two ounces, and of flarch one ounce $ 
 diflblve, then, in this extrafl, two pounds and 
 a half of fugar ; and, laftly, mix with it, the 
 fugar being firft diflblved, a powder com- 
 pounded of fixteen ounces of crabs claws, 
 two ounces of cinnamon and nutmeg, and 
 one ounce of cloves. 
 
 Note, 
 
 By this redu&ion of the quantity of the fluid, 
 and infpiflating the remainder by the gum ara- 
 bic and ftarch, together with the augmented 
 quantity of the fugar, the composition is rendered 
 of the due confiftence of an eleftuary, without 
 altering the weight of the whole, or changing 
 the proportion of any of the ingredients ; ex- 
 cept 
 
336 Galenical Preparations. 
 
 cept the fugar, of which, the half pound, toal-> 
 low for the evaporation of part of the fluid, 
 cannot be fuppofed to make any difference in 
 die efficacy of the medicine. 
 
 By diftilling the rofemary with the propor- 
 tion of fpirit of wine here direded, fix pints of 
 Hungary water is gained without the leaft in- 
 jury to the extract : as is, likewife, by the fame 
 means, a gallon of Geneva, equal to the beft 
 made in Holland, for the additional expence of 
 half a gallon of proof fpirit. 
 
 Gafcoigris powder. 
 
 Take, of prepared pearls, crabs -eyes, red 
 coral, the whiteft amber, calcined hartf- 
 horn, and oriental bezoar, each one ounce 2 
 of the tips of crabs claws powdered, the 
 weight of all the others : make them into a 
 fine powder; and afterwards form them in- 
 to balls, by means of a folution of gum 
 
 arabic. 
 
 Note. 
 
 This compofition, which, from the caprice 
 and folly of mankind, has been in very great 
 vogue, differs materially from other teftaceous 
 powders in nothing, but the very great expen- 
 fivenefs of fome of its ingredients. It has, 
 therefore, been feldom prepared with a ftrid: 
 conformity to the prescription here given 5 
 
 which 
 
Galenical Preparations. 337 
 
 which is that of the former edition of the Di£- 
 penfatory of the London college ; but altered* 
 according to the fancy or parcimony of the 
 preparers ; and now rnoft frequently excluded 
 from the fhops by the fubftitution of a coun- 
 terfeit mixture* which does not contain even 
 one of the proper ingredients. But before I give 
 the recipe for this abfolute counterfeit, I will 
 give one for fuch, as avoiding the rnoft coftly of 
 the ingredients, at the fame time comprehends ' 
 all that are materially necefiary. 
 
 Cheaper method of preparing Gafcoigns pow~ 
 der without altering its efficacy. 
 
 Take, of crabs claws feven ounces, of cal^ 
 cined hartfhorn, and amber, each one ounce, 
 of the feed of the amomum Plinij, dried 
 and powdered, two drams : all the ingre- 
 dients being levigated together, make the 
 mixture into balls, by a folution of gum 
 Arabic. 
 
 Note. 
 
 The crabs claws being no way different, with 
 regard to their medicinal virtue, from the pearls, 
 coral, or crabs eyes, the quantity of it is in- 
 creafed to fupply their place ; and the feeds of 
 the amomum, which have been difcovered to 
 give the colour when rubbed on paper, which 
 was made the teft of the genuinenefs of thi9 
 
 Z medi- 
 
338 Galenical Preparations; 
 
 medicine, is, on that account, added in the 
 place of the bezoar : and this compofition is 
 in fad: equally good with that prepared in the 
 moft expenfive manner, as all the bodies of the 
 teftaceous kind have the fame qualities \ and 
 coral, though differently produced, has a ftrid: 
 affinity with them. But cheaply as this may 
 be prepared, the common fubftitute, above- 
 mentioned, for the Gafcoign's powder deviates 
 wholly from it ; being compofed of fubftances 
 varying even from the nature of the true in- 
 gredients ; as it is compofed of foffile earths, 
 inftead of the teftaceous parts of animals ; 
 and, therefore, according to what we before ob- 
 ferved in the introductory part, eflentially dif- 
 ferent. But that the impofition may be the bet- 
 ter known, I will give here the recipe for the 
 preparation. 
 
 Method of preparing the counterfeit Gafcoigns 
 . powder commonly fold. 
 
 Take, of chalk, one pound, of tobacco- 
 pipe clay, dried and powdered, half a 
 pound, of the feed of the amomum Plinij, 
 half an ounce : levigate them well together; 
 and form them into balls. 
 
 Note. 
 
 This clumfy mixture has fo much the ap- 
 pearance of the Gafcoign's powder, that from 
 the refemblance, and the cheap price it is fold 
 
 for 
 
Galenical Preparations. 339 
 
 For by-thofe who prepare it, (which I believe 
 is not more than four or five (hillings per 
 pound,) it has become the common fort ufedj 
 clpecially in the country where preparations 
 of this kind are generally had from druggifts^ 
 who neither know nor care any thing more 
 about medicines, than where fuch as are paffa- 
 ble may be moft cheaply purchafed. 
 
 As it is of fome confequence, therefore, to 
 be able to diftiiiguifh this counterfeit from the 
 other kind, I would advife the putting a ball of 
 any fufpefted into the fire -> which, if it be 
 compofed of tobacco pipe clay and chalk, will- 
 harden ; but, if of the teilaceous fubfiances pro- 
 per to the medicine cemented together with 
 gum Arabic, will grow foft and crumbly: the 
 gum Arabic which caufed the tenacity, being 
 deftroyed by the fire, and the teftacea calcined* 
 
 Gmjlone. 
 Take, of. hyacynths, topazzes, fap- 
 phires, rubies, and pearls, each an ounce, 
 of oriental bezoar, white coral, and red 
 coral, each two ounces, of emeralds, half an 
 ounce, of mufk, and ambergrife, each two 
 drams, of leaves of gold, number forty : let 
 all be levigated into an impalpable powder j 
 and, with rofe-vvater, made into a pafte $ 
 which is to be formed into long or oval 
 balls, and polifhed* 
 
 Z % Note. 
 
340 Galenical Preparations; 
 
 Note. 
 
 The great expenfivenefs of the precious 
 {tones in this preparation, from which, like- 
 wife, it receives not the leaft addition to its 
 efficacy, has occafioned fubftitutions of various 
 kinds to be made for it : in which, alfo, the 
 admixture of the leaf gold, with the other in- 
 gredients, has been omitted ; as it was no way 
 neceffary, but for the gilded appearance, that 
 may be equally well produced with a much 
 lefs quantity ufed differently. 
 
 The Goa ftone, therefore, according to the 
 prefent ufage of the {hops, may be prepared 
 in the following manner. 
 
 V 
 
 Method of preparing the Goaf ones , as they are 
 now found in the /hops. 
 
 Take, of crabs claws levigated, eight 
 ounces, of oyfter fliells levigated, four 
 ounces, of mufk, and ambergrife, each two 
 drams : mix them well - y an4 make them 
 into a pafte with rofe water, in which gum 
 arabic is difTolved, in the proportion of a 
 dram to two ounces : make this pafte into 
 round or oblong balls ; and, when they are 
 dry, dip them in a ftrong folution of gum 
 arabic ; and roll them on leaves of gold, 
 till their furface be wholly covered ; and, 
 3 when 
 
Galenical Preparations. 341 
 when again dry, rub them with a cloth to 
 give them a polifli. 
 
 Volatile tintture of bark. 
 
 Take, of the Peruvian bark, four ounces, 
 volatile fpirit of fal ammoniacum, two pints, 
 digeft them, without heat, in a veffel well 
 clofed 5 and ftrain off the tin<5ture. 
 
 Note. 
 
 The college have directed no volatile fpirit 
 to be made but with fixt alkaline fait 3 and 
 wholly prohibited the ufe of lime for that pur- 
 pofe : now this tin<flure cannot be made of 
 any volatile fpirit but what is prepared with 
 lime ; for with the fpirit made by fixt alka- 
 line falts, nothing can be produced but a thick 
 mucilage from the infufion of the bark : from 
 which circumftance, many, who have at- 
 tempted, to make this tin<5ture, have mifcar- 
 ried ; and found it impracticable. 
 
 Whoever, therefore, would prepare this me- 
 dicine, muft ufe volatile fpirit of fal ammonia- 
 cum made with lime, inftead of that made by 
 fixt alkaline fait. 
 
 B a If am of fulphar. 
 
 Take, of olive oil, one pound, of flowers 
 of fulphur, four ounces : put them into a 
 
 Z f pipkin 5 
 
34 2 Galenical Preparations. 
 pipkin, that will contain about three times 
 their quantity - y and fet it over a fire, and 
 make the matter boil gently : keep it con- 
 tinually ftirring, with a wooden fpatula, for 
 the fpace of an hour and half, till it is quite 
 cool : and put it up for ufe. 
 
 Note. 
 
 This is conformable to the prefcription of 
 the college of London : but-the medicine is 
 generally made in a cheaper manner ; by Tub- 
 ltituting the linfeed oil inftead of that of olives \ 
 by increafing the quantity of fulphur ; and by 
 ufing the crude or roll fulphur inftead of the 
 flowers : for which method of preparation this 
 is the general procefs. 
 
 Common method of preparing half am of fulphur * 
 
 Take, of linfeed oil, one gallon, and of 
 crude, or roll fulphur, four pounds : put the 
 oil into an earthen pipkin, which will hold 
 about two gallons -, and fet it over a fire, 
 that will only make it boil in the moft gentle 
 manner : powder the fulphur $ and throw it, 
 gradually, into the boiling oil ; at firft in 
 greater quantities, and afterwards more gra- 
 dually; ftirring the mixture* .with a wooden 
 
 fpatula 1 
 
Galenical Preparations. 343 
 
 Ipatula ; and letting one quantity be dif- 
 
 ,iblved before another be added ; when the 
 
 whole quantity of fulphur is diflblved, the 
 
 preparation is finifhed. 
 
 Note. 
 
 By this means, the balfam of fulphur is 
 prepared at a very fmall expence : and, though 
 in the moft regular manner the coft is fo little, 
 that there feems no temptation to deviate from 
 it ; yet the farriers, who make the principal 
 demned for it, ufe it in fuch large quantities, 
 that the greatnefs of the confumption makes it 
 worth while for the wholefale dealers to con- 
 fult of fuch favings, as are made by this pro- 
 cefs. 
 
 With refpeft to its ufe in regular medicine, 
 the fubftitiition of linfeed, for olive oil, is not 
 very exceptionable : there is indeed fo little ap- 
 parent foundation, for a preference of either, 
 that the college of Edinburg have left it wholly 
 to the choice of the preparer, which to em- 
 ploy. 
 
 The ufe of crude fulphur, inftead of the 
 flowers, is not much more to be objeded to ; for 
 they differ only in purity : and, if the roll ful- 
 phur be good, no difference will be found in 
 the medicine. 
 
 As to the efficacy of the medicine, one would 
 imagine, that the increafe of the quantity of 
 fulphur would be rather beneficial than other- 
 
 Z 4 wife ; 
 
344 Galenical Preparations. 
 wife : as the oil can only be confidered, as 
 the vehicle of it. The only reafon, therefore, 
 of limitation of the proportion, feems to be; 
 that, if too much fulphur be added, the fluid 
 form of the mixture, which it will retain with 
 this quantity, is apt to be deftroyed : as I have 
 frequently feen, where a yet greater quantity 
 of fulphur than is here directed has been ufed: 
 and this renders it incommodious to take out 
 of the vefTels when it is fold, or ufed. 
 
 Acid elixir of vitrioL 
 
 Take, of cinnamon fix drams, of lefler 
 cardamom feeds hulked, three drams, of 
 long pepper, and ginger, each two drams : 
 infufe without heat ; and filter off the tinc- 
 ture : to this add of oil of vitriol, fixtcen 
 ounces j and filter* 
 
 Note. 
 
 This medicine is feldom prepared for fale 
 according to the prefcription of the college 
 here given, the quantity of the fpices being fo 
 fmall, that they neither produce the refem- 
 blance, in fcentor colour, of the former elixir ; 
 and therefore, render this compofition lefs a^ 
 greeable to thofe, who are accuftomed to the 
 other. 
 
 The former prefcription of the college or- 
 dered twelve ingredients to be ufed, befides the 
 
 fpirit 
 
Galenical Preparations. 345 
 
 fpirit of wine, and oil of vitriol ; but a great 
 part of them, being unneceffary ; and fome of 
 them abfurd with refpedt to the intention, are 
 generally omitted; and other proportions of the 
 remaining are employed in their ftead : the 
 Jamaica pepper has been fubftituted by feveral 
 inftead of fome of the dearer fpices 3 not be- 
 ing eafily diftinguifhable, in the tincture, from 
 them. The effential oils of fage and mint 
 have been fome times ufed, inftead of the 
 leaves ; and are now ordered by the Edin- 
 burg college : but, as the London college wholly 
 omit both, the following recipe, if any fubfti- 
 tution be allowed, may be confidered as one of 
 the beft 3 as, by it, not only a ftrong tin&ure 
 for the elixir is made, very cheaply, but the 
 composition is greatly correfpondent to the a- 
 bpve prefcription ; at the fame time the appear- 
 ance of the medicine will be rendered very con- 
 formable to that of the old eftablifhed elixir. 
 
 Cheap method of preparing the elixir of vitriol, 
 in the moji perfeSi manner. 
 
 Take, of proof fpirit of wine, two pints, 
 of Jamaica pepper, one ounce and half, of 
 caffia lignea, and ginger, each one ounce : 
 pound the fpices ; and put them, with the 
 fpirit of wine, into a mattrafs with a cir- 
 culating head y and, after an infufion of 
 
 feveral 
 
346 Galenical Preparations^ 
 feveral days, flrain off the tin&ure : t<3 
 which add fixteen ounces of oil of vitriol 
 very gradually. 
 
 Note. 
 
 This tin&ure being much more rich of the 
 fpices, than that made according to the college 
 prefcription, will have a much ftronger fcent ; 
 and acquire, after keeping fome time, the red 
 colour, which is produced by the a&ion of the 
 oil of vitriol on the eflential oils of the fpices, 
 and is neceffary for the faleable appearance of 
 this medicine ; and, if the fpices can be fop- 
 pofed to add any efficacy to the compofition, 
 this mull be preferable to that prepared by the 
 regular procefs ; where the quantity ih a dofe 
 is fo minute, that no pofiible effetft can be ex- 
 pefted from it. 
 
 Sweet elixir of vitriol. 
 
 Take, of cinnamon fix drams, of lefler 
 cardamom feeds, hufked, three drams, of 
 long pepper, and ginger, each two drams > 
 'of proof fpirit of wine, two pints : infufe 
 without heat ; and filter off the tin£ture : to 
 which, add of fpiritus vitrioli dulcis fixteen 
 ounces* 
 
 1 Note* 
 
Galenical Preparations^ 347 
 
 Note. 
 
 This is the prefcription of the college of 
 London, for the fweet elixir; and is, in fa£t, 
 a fubftitution for Vigani's elixir of vitriol, which 
 the college of Edinburg, omitting the green 
 colour, have adopted as the only kind directed 
 by them. But sis the demand for Vigani's is 
 yet continued, and the preparation of it kept 
 as a fecret in the hands of fome particular peo- 
 ple, I will here give the method of making it. 
 
 Vigani's elixir of 'vitriol. 
 
 Take, of the blades of green corn, or the 
 leaves of fpinage, a proper quantity : bruife 
 them well, in a mortar of glafs or marble ; 
 and then prefs out the green juice from 
 them : put two ounces of this green juice, 
 or as much as will raife the defired colour, 
 into a pint of fpiritus vitrioli dulcis; and 
 add to it, dropping them in very gradually, 
 of the oil of mint, two drams, of the oil 
 diftilled from lemon peels, and nutmegs, (or 
 Jamaica pepper), each one dram : incor- 
 porate them thoroughly ; and, if any fmall 
 quantity of the oil remain unmixed, let it be 
 taken away by means of a feparating funnel. 
 
 Or, 
 
348 Galenical Preparations. 
 
 Or, an ounce of Jamaica pepper, dried 
 leaves of mint and lemon peel, the two firfl 
 being powdered, and the laft bruifed, may- 
 be infufed, with a gentle heat, for fome 
 days, in a pint of fpiritus vitrioli dulcis co- 
 loured as above; and the tin<5ture then poured, 
 or {trained, off from the dry ingredients. 
 
 Note. 
 
 The green colour of this elixir is the fecret, 
 which has kept this preparation in particular 
 hands ; but it may be produced by the above 
 means ; or by infufing the feeds of the amo- 
 mum Plinij, in the fpiritus vitrioli dulcis, toge- 
 ther with faffron, or yellow fanders. 
 
 Daffy s elixir, or elixir falutis. 
 
 Take, of jalap, one pound and half, of fena, 
 leaves, half a pound, of anifeed, three ounces, 
 of coriander feeds, two ounces, of orange 
 peel, one ounce, of proof fpirit of wine > one 
 gallon : having powdered the jalap, and 
 bruifed the feeds, infufe them for eight, or 
 ten days -, after fhaking the veffeL 
 
 Note. 
 
 The fale of compositions under the name of 
 Daffy's elixir, being very great, many perfons 
 
 have 
 
Galenical Preparations* 349 
 
 have made the preparation of it, with a few 
 other things of a like kind, their particular 
 buiinefsj and all methods have, therefore, been 
 tried to prepare it as cheap as poffible. The 
 principal view is to have a cheap purgative 
 joined to the anife and coriander feeds, in- 
 ftead of the ufing the fena alone ; and this is 
 beft done by the jalap ; which neither gives 
 the bitter flavour, nor is apt to gripe, as the 
 aloes, its rival in cheapnefs. This prefcription 
 may, therefore, be efteemed the beft for the 
 Daffy's elixir, both for the palatablenefs and 
 mild efficacy : and the proportion of the pur- 
 gative ingredients is nearly correfpondent to 
 that of the college tin&ures. 
 
 Syrup of capillair] 
 
 Take, of maiden hair, one ounce, of 
 liquorice flipped into thin bits, two ounces : 
 pour upon them a quart of boiling water ; 
 and let them infufe in it one day : then 
 ftrain off the fluid through flannel ; and 
 diffolve in it, being fet on the fire in a pro- 
 per veflel to boil j four pounds of eight- 
 penny fugar -, taking off the fcum as it rifes : 
 as foon as the whole of the fugar is dif- 
 folved, and the fyrup has boiled eight or 
 ten minutes, take it off the fire : and, when 
 
 cold, 
 
$5o Galenical Preparations. 
 cold, add two ounces of orange flower wa- 
 ter ; mixing it well with the fyrup by Hir- 
 ing, or fhaking them together* 
 
 Note. 
 
 The conftant ufe of this fyrup at coffee- 
 houfes, and elfewhere, as a regale, has occa- 
 fioned it to be prepared in the cheapeft man- 
 ner that could be contrived ; which has been 
 firft by ufing only the fyrup of fugar, and a 
 little orange flower water; and afterwards 
 omitting even two or three parts of the proper 
 quantity of fugar, and thickning the fyrup 
 with ftarch, in order to make it appear of the 
 due confiftence, and to prevent its fermen- 
 tation, which would otherwife neceffarily hap- 
 pen. But thofe who are not difpofed to enter 
 into fuch fraudulent practices, and would pre- 
 pare this fyrup genuinely cheap, may ufe the 
 above prescription ; which differs only from 
 the officinal ones in leffening the quantity of 
 the maiden hair, that, in a greater proportion, 
 would render the fyrup bitter and unpalatable. 
 
 PART 
 
PART IV. 
 
 Of the fubftitutions and adulterations, 
 commonly pra&ifed with refpedt to 
 the fimples ; and the proper methods 
 of deteding them in each inftance. 
 
 Adulteration of quickfiher ; and the means of 
 its detection. 
 
 QUICKSILVER, though of at lead 
 equal importance with any other me- 
 dicinal fimple, is, perhaps, more frequently 
 adulterated than any other : and, by that 
 means, rendered greatly unfit for thofe pre- 
 parations, where it does not undergo a 
 fublimation ; as in the feveral precipitates, 
 ^thiops mineral, and alcalifate mercury. 
 
 The adulteration is made by amalgamat- 
 ing lead or tin with the quickfilver ; which 
 metals it readily diffolves, and apparently 
 affimilates with itfelf. 
 
 As this adulteration, particularly with 
 lead, ought to be carefully guarded againft, 
 where quickfilver is ufed for the abovemen- 
 
 tioned 
 
35^ Adulterations and 
 tioned purpofes, it ought always to be proved 
 by a proper teft. 
 
 The eafieft means of doing this, where 
 the adulteration is great, is by {training it 
 through leather ; in which, if it contain 
 beyond a certain proportion of lead or tin, 
 a pafty metallic matter will be left - y being 
 an amalgama of the two metals : but, if 
 the adulteration be fmall, this proof will 
 not difcover it ; and the following method 
 fhould be ufed. 
 
 Put any quantity of the quickfilver fu- 
 Jpe£ted into a crucible; and give it fuch 
 a heat, as will diffipate it in fumes : after 
 which the tin or lead, if there be any, will 
 be left in the crucible ; and being examined 
 and weighed, not only the nature, but the 
 proportionate quantity of the adulterating 
 matter in the quickfilver, may be with cer- 
 tainty known : fo that, the quickfilver may 
 be either purified for the ufes, which re- 
 quire it, according to the means direfted 
 p. 208 ; or applied to the purpofes where 
 purity is not efTential ; proper allowance 
 being made for the defeft in quantity 
 
 of 
 
Substitutions. 353 
 
 of the real quickfilver, proportionably to the 
 weight caufed by this adulteration* 
 
 Bubjlitution for native cinnabar. 
 
 The native cinnabar bearing a confidera- 
 ble price, the factitious cinnabar, which, 
 when prepared with a great proportion of 
 fulphur, extremely refembles it, is very fre- 
 quently fubftituted for it. 
 
 As they are in faCt the fame, the native 
 cinnabar, as well as the factitious, being 
 only a combination of quickfilver and ful- 
 phur, and that, likewife, in various propor- 
 tions in different parcels, there is no poffi- 
 bility of difcovering this fubftitution : ami 
 it is beft, therefore, to avoid the ufe of this 
 fubftance as a medicine ; and to be fatisfied 
 with the fadlitious under its own name ; as 
 there can be no certainty, in the common 
 courfe of praCtice, of having the genuine 
 native j and as, when it is had in the molt 
 genuine ftate, it is no way different from, 
 the factitious, but in the manner of its pro- 
 duction. 
 
 A a AduU 
 
354 Adulterations and 
 
 Adulteration of white lead, or cerufs ; and 
 the means of its detection. 
 
 White lead, though of fmall price, 
 yet being confumed for the purpofes of 
 painting in great quantities, is, for the 
 moll part, adulterated by the manufac- 
 turers, or wholefale dealers in it ; and, 
 in this ftate, confequently, procured for 
 the moft part as a fimple in medicine. 
 
 The common adulteration is with chalk 
 or talc ; as being the cheapeft ingredients, 
 with which it can be fophifticated : this, 
 in a lefler degree, is of no great moment 
 with regard to the medicinal ufes of this 
 fubftance, which are principally for the 
 making plaifters, or unguents. But, in 
 a greater proportion, fuch mixtures of 
 heterogeneous matter deprave it highly for 
 fome applications. 
 
 The adulteration may be, therefore, ex- 
 amined moft eafily, by comparing a piece 
 of what is fufpe£ted with another piece, 
 Jknown to be pure, of equal bulk - y and 
 the difference of weight will fliew the 
 
 fraud, 
 
Substitutions. 35.5 
 
 fraud, where the fophiflication is in a 
 great proportion. But, where the quan- 
 tity of adulterating matter is lefs, or the 
 proportion of it would be more exactly 
 known, the following manner fhould be 
 ufed. 
 
 Take an ounce of the white u ad fu- 
 fpe£ted y and mix it well with about half 
 an ounce of pearl-afhes, or of an ; t 
 alkaline fait, and about a quarter of an 
 ounce of charcoal duft - y aftd, having 
 put them into a crucible, give them a 
 ftrong heat. The lead will, by this means, 
 be reduced, to its metallic flate ; and, being 
 weighed, will fhew, by what it may fall 
 fhort of the weight of an ounce, the pro- 
 portion of the adulteration : about a tenth 
 part being allowed for the corroding acid 
 pf the white lead. 
 
 Adulteration of red lead, or mtjiium ; and the 
 means of its detedlton. 
 
 The red lead is neither fo frequently nor 
 
 largely adulterated as the white : becaufe of 
 
 the vifible effe£t any admixture of fuch in- 
 
 A a z gre- 
 
356 Adulteration and 
 gredients as are of lefs value would have 
 on its bright colour. It fs, however, fome- 
 times adulterated with red oker - y which 
 may be perceived, by comparing the fophifti- 
 cated with a fpecimen of the true, from the 
 foulnefs which will be produced in the bright 
 orange colour. But any adulteration may 
 be with certainty known by reducing it to its 
 metallic ftate, through the means above given 
 for the white lead : the pearl-afhes being in 
 this cafe omitted. 
 
 Subflitution for gum arable. 
 
 The gum fenegal, wkich can be afforded 
 at a much cheaper rate, is very frequently 
 fold or ufed for medicinal purpofes in the 
 place of the gum arabic : but as they are, 
 as far as appears, alike in their qualities 
 with refpeft to their ufe in medicine, it is 
 not a very hurtful fraud. 
 
 As it is proper, however, to prevent im- 
 pofitions with refpeft to price, that they 
 ffrould be diftinguifhed : whoever has oc- 
 cafion may difcer'n the difference, by the 
 dry and brittle confidence of gum arabic ; 
 
 the 
 
Substitutions.. 357 
 the other being clammy and tenacious, like 
 the gums produced, in our own country, 
 from the plumb or cherry trees. 
 
 Subjliiution for the true fperma cceti. 
 
 The form and confiftence of fperma coeti 
 not being owing to the ftate or nature of 
 the oil, of which it is made, when taken 
 from the whale, but to an artificial concre- 
 tion produced by the addition of faline bo- 
 dies, the fame art is praftifed on other 
 animal oils \ even on the moft feculent part 
 of the train oil, and that extra6led from pil- 
 chards: and the fi&itious fperma cceti, thus 
 prepared, is fold, and ufed, in common, 
 with that prepared from the proper part of 
 the fat of the whale. 
 
 As, however, the nature of animal oils is 
 the fame in all refpe&s, except with regard 
 to confiftence, and their fweet or putrid 
 ftate, and as all fuch oils are rendered alike 
 folid and fweet, by that treatment of them, 
 by which the fperma cceti is prepared, the 
 fubftitution of train, or other oils, inftead 
 of that originally ufed, cannot be accounted 
 A a 3 an 
 
358 Adulterations and 
 an injurious fraud, with refpeft to medi- 
 cine , and, with refpecl to other puipofes, it 
 will be a very valuable improvement. 
 
 Subftitution for cinnamon. 
 
 The cafiia lignea is, for moft purpofes, 
 fubftituted for cinnamon, by thofe who 
 fludy the cheap preparation of medicines : 
 it is, likewife, very frequently mixed with 
 the true cinnamon 5 and fometimes fold 
 intirely for it. 
 
 With refpe£t to the medicinal efficacy, 
 this fubftitution may be confidered as al- 
 lowable : for there is no experimental dif- 
 ference to be found in the eflential oils (in 
 which alone the efficacy of this drug lies) 
 betwixt the two kinds ; and a very ingeni- 
 ous gentleman, whofe veracity cannot be 
 queftioned, after having particularly taken 
 upon him to inquire after this matter in 
 the Eaft- Indies, is fatisfied, that they are the 
 bark of the fame tree ; and only differ in 
 the manner of curing, and the choice 
 with regard to the parts and age of the 
 tree. • • 
 
 The 
 
Substitutions; 35$ 
 
 The caffia, however, as it is here im- 
 ported, may be eafily diftinguifhed from the 
 cinnamon, by thofe who have occafion, 
 from a fweet mucilage, which it affords on 
 taking it into the mouth, where it feems, if 
 good, almofi wholly to diflblve : whereas 
 the cinnamon taftes hotter ; and has a 
 bitter drynefs in the mouth : the caffia, 
 likewife, fhews itfelf, when infufed in 
 fpirit of wine, by imparting a ftrong 
 yellow colour to it, not found in near 
 fo great a proportion in the cinnamon : 
 the quills of the cinnamon bark are, like- 
 wife, generally much thinner and fmoother 
 than the caffia. 
 
 Adulteration of vinegar ; and the means of its 
 deteSlion. 
 
 Vinegar prepared in the great works 
 near London is generally adulterated with 
 oil of vitriol. This fophiftication does not, 
 however, greatly injure it for medicinal ufes, 
 when it is not in a great degree : but where, 
 as I have {qqxi it, a confiderable part of the 
 acid is only from the oil of vitriol added, 
 
 A a 4 the 
 
360 Adulterations and 
 the ufing fuch for diflillation, or for mat- 
 ing the fugar of lead, and feveral other pur- 
 poles, is attended with great lofs and incon- 
 venience. 
 
 In order, therefore, to diftinguifhthe vine- 
 gar fo adulterated from the purer, where the 
 tafte Is not thought a fufiicient evidence of 
 this fraud, the following method may be 
 ufed. 
 
 Take a quart of the vinegar ; and boil it 
 down to about two ounces : into the re- 
 mainder, put' two drams of any fixt alka- 
 line fait : which, being diffolved, pour on 
 two or three ounces of water 5 and filter 
 the folution : evaporate, then, the fluid 
 to about half an ounce ; and, if there were 
 any oil of vitriol in the vinegar, chryftals of 
 the vitriolate tartar will be found 3 which 
 may be eafily known by their tafte, or pecu- 
 liar form fimilar to that of the mineral 
 chryftal, only with a greater thicknefs pro- 
 portionably to their length. 
 
 The refiduum in the retort* or veflel, after 
 the diftillation of vinegar may be ufed for 
 tills trial inftead of the vinegar itfelf : by 
 
 which 
 
Substitutions. 361 
 
 which means the evaporation may be faved; 
 and, as a confiderable quantity may be this 
 way ufed without expence, the proportion 
 of the oil of vitriol may be nearly afcer- 
 tained by the quantity of tartar vitriolate 
 produced, which may be feparated, from 
 the fal diureticus that will be formed from 
 the remaining part of the acetous acid, by 
 a careful chryftallization, 
 
 Sophifticaticn of faffron. 
 
 The foreign faffron is almoft conftantly 
 fophifticated with oil ; by which means 
 the weight is increafed in a great difpro- 
 portion to that of the pure faffron ; and 
 the flavour of it, alfo, frequently depraved. 
 It is ufual, moreover, for dealers in me- 
 dicine to prepare the foreign faffron, by 
 extra£ling the oil from it, and prefling it 
 into cakes of the fame form with thofe 
 of the Englifh ; and to pafs it off for the 
 Englifh ; to which it is greatly inferior in 
 all refpe&s. 
 
 This impofition cannot be difcovered by 
 any other means, than the learning the true 
 
 appear* 
 
36# Adulterations and 
 appearance of the beft faffron, or the keep- 
 ing a good fpecimen to compare with any 
 that may be queftionable : where the ftrcng 
 aromatic fmell, and deep clear colour, will 
 eafily fhew the difference betwixt the foreign 
 and EnglifL 
 
 Adulteration of pcarl-ajhcs. 
 
 The pearl-afhes* which both from the 
 adoption of them by the college, and their 
 frequent ufe in the chemical practice, are 
 now become a material fimple, are, for the 
 molt part, adulterated with fea-falt in a 
 greater or lefs degree. As the fea fait is of 
 an innocent nature, there is no great mif- 
 chief arifes from this, when in a moderate 
 degree : but where the adulteration is great, 
 a lofs arifes from the deficience of the fixt al- 
 kaline fait, in the preparations where the 
 pearl afhes are ufed. In order, therefore, 
 to guard againft the taking any fuch, it is 
 very proper to try them, by laying a little 
 on a red-hot poker ; where, if any quan- 
 tity of .fea fait has been added after the pearl 
 afhes have been calcined, it will inevitably 
 
 fhow 
 
Substitutions. 363 
 
 fhow itfelf by its decrepitation or crackling 
 noife. 
 
 Subjlitution for pearls. 
 
 It is ufual, where prepared pearls are to 
 be ufed or fold, to fubflitute prepared oyfter 
 fhells in their place ; which, when reduced 
 to impalpable powder, are indiftinguifha- 
 ble from them, being in fa6fc the fame fub- 
 fiance ; for which reafon it were to be wifhed 
 that the college had thrown them out of 
 the materia medica in the late reforma- 
 tion of their pharmacopeia : and that the 
 credulity in old forms did not give fo much 
 occafion to impofition of this kind ; which, 
 however innocent with refpeft to the medi- 
 cinal confequences, are yet a fort of com- 
 mercial fraud, that will be unavoidably prac- 
 tifed, while authority countenances the pre- 
 fcription of fubftances very fcarce or dear, 
 which have others refembling them in ap- 
 pearance, and agreeing with them in their 
 
 qualities. 
 t 
 
 Subjlitution for crabs eyes. 
 
 As prepared oyfter fhells are fubftituted 
 for pearls, fo crabs claws are/ for the molt 
 
 3 P a rt> 
 
364 Adulterations and 
 part, fold or ufed, where erabs eyes are 
 demanded or ordered ; and for the fame 
 reafon : there being, in faft, no dif- 
 ference betwixt them, but the form in 
 which, and fituation where, they are pro- 
 duced in the crab. 
 
 Thefe ought, therefore, along with the 
 pearls and other fuch fubftances as have no 
 dTential fuperiority over the reft of the 
 genus to which they belong, and are diffi- 
 cult to be collected, or of great price, to 
 be excluded from the materia medica : bv 
 which means, the preparers of medicines 
 would not have their confcience forced by 
 the temptation, the opportunity of prac- 
 ticing the arts of fophiftication and fubfti- 
 tution gives, while coftly medicines are in 
 ufe : nor would the prefcribers or pur- 
 chafers be liable to fuch deceptions ; but cer- 
 tain in general of really having what they 
 wrote, or paid, for. 
 
 Subftitution for the teftacea in general. 
 
 Chalk is very frequently fubftituted for, 
 or mixed with, all the prepared teftacea. 
 
 This 
 
Substitutions. 365 
 
 This is much lefs allowable* than the chang- 
 ing any of the teftacea for each other $ for, 
 though chalk be, as well as the teftaceous 
 genus, of an alkaline nature ; and will neu- 
 tralize acids in the via prima to a certain 
 degree 5 yet it will much lefs effectually do fo 
 than the others ; and has, befides, a flyptic 
 aftringent power, by which, it increafes 
 coftivenefs, in many habits, to a very de- 
 trimental degree. 
 
 The method of difcovering where chalk 
 is fubftituted for, or mixed with,* the -tefta- 
 ceous earths, is to pour oil of vitriol upon 
 the fufpe£ted quantity ; which will readily 
 diffolve the tefyaceous earths, but leaves the 
 greateft part of the chalk unchanged ; by 
 which means, the fraud may be eafily de- 
 te6ted. But this is not pra&icable where 
 the teftacea have undergone a ftrong cal- 
 cination ; for, being rendered of a calcari- 
 ous nature, they have then a great affinity 
 with chalk - y and will refill the folvent power 
 of the oil of vitriol, when they are divefled 
 of their fulphureous or phlogiftic part. 
 
 Chalk 
 
366 Adulterations and 
 
 Chalk may f>e, likewife, diftinguiflied 
 from the levigated teftacea, by the tafle ; 
 which is much more auftere and rough in 
 the firft, than in the others : but this cri- 
 terion cannot be extended tQ a mixture of 
 them, where the proportion of the chalk 
 may be fmall. 
 
 Subftitution for the buckthorn berries. 
 
 The buckthorn berries being one of the 
 moft common cathartic medicines, and con- 
 fequently ufed in a confiderable quantity, it 
 is very frequent for thofe, who colleft them, 
 to put off in their place, and intermix with 
 them, the berries of other trees and plants , 
 particularly thofe of the frangula, or black 
 alder, which greatly referable them in their 
 appearance. 
 
 As this ought to be carefully guarded, a- 
 gainft, on account of the error it may oc- 
 cafion in the ftrength of the fyrup of buck- 
 thorn, which is a medicine frequently much 
 depended upon, it is proper to examine well 
 fuch parcels of berries, as are not had from 
 the hands of thofe who can be well con- 
 fided 
 
Substitutions. 367 
 
 fided in : and the true buckthorn berries 
 may be diftinguifhed, by their three cornered 
 feeds, with a purplifh juice intermixed with 
 green. 
 
 The juice of the buckthorn berries, which 
 is fometimes bought of thofe who gather 
 them, and exprefs it to fave the carriage of 
 the berries, where they are to be difpofed of 
 at a diftance, is very liable, alfo, to be adul- 
 terated by the admixture of water, or any 
 other fluid which may refemble it. Againft 
 this there is no means of fecurity, but the 
 avoiding being concerned with the juice al- 
 ready extrafted from the berries ; and ufing 
 them alone, as they may, generally, be 
 as eafily procured, as the juice, with a 
 fmall difference in the proportion of the 
 price. 
 
 Subjiitution for oil of cinnamon. 
 
 The effential oils of the caffia and cinna- 
 mon, (and probably the trees affording the 
 barks) as we have obferved before, being 
 the fame, the oil of caffia is in general fub- 
 ilituted for the other, it being now a com- 
 mon 
 
368 Adulterations and 
 mon practice at Bencoolen, and other places 
 in the Eaft-Indies, as well as in England, 
 to diftill it for that purpofe* 
 
 As it is fo much a doubt, whether there 
 be any difference in nature betwixt them, 
 there can confequently be no artificial means 
 of diftinguifhing them : nor for the fame 
 reafon any juft ground of follicitude about 
 fuch means. 
 
 Subjlitutionfor oil of cloves ; with the adultera- 
 tion of the genuine. 
 
 If Jamaica pepper be diflilled, it affords 
 an oil greatly refembling that of cloves, 
 both in its appearance, flavour, and fcent. 
 It is, therefore, frequently mixed with the 
 oil of cloves s and fometimes put off for 
 it. 
 
 There is no method of diftinguifhing 
 this fraud, but by comparing a fpecimen of 
 pure oil of cloves with what is fufpe£ted; 
 and judging by the colour and fcent ; 
 the true oil of cloves being of a lighter 
 orange brown colour, and a much higher 
 aromatic fmell, than that of the pepper ; 
 
 which 
 
S UB STITUTIONS. 369 
 
 which has a more thick black appearance, 
 and fainter odour. 
 
 The oil of cloves is, likewife, frequently 
 adulterated with the oil of olives, or of lin- 
 feed 5 which may be difcovered by placing 
 fome of it, in a phial, in a cold cellar : where, 
 .on (landing at reft, for a long time, the oil 
 of cloves will fhew itfelf feparated, by fub- 
 Tiding to the bottom. This fraud may, alfo, 
 be difcovered by dropping the oil of cloves 
 into very highly re6lified fpirit of wine, and 
 mixing them well by fhaking ; where, be- 
 ing attra&ed by, and combined with, the 
 fpirit, the oil of olives will fwim on the fur- 
 face, or appear in fmall globules. 
 
 Adulteration of ejfence of lemons. 
 
 The eflence of lemons is frequently adul- 
 terated, as well as the oil of cloves, by the 
 admixture of common oils. The fraud may 
 be difcovered, in the fame manner, by its 
 admixture with highly re&ified fpirit ; or 
 by diftilling any quantity of it, in a fmall 
 retort, with water ; where the eflence riiing 
 will be re&ified -, and leave the oil behind in. 
 
 B b the 
 
370 Adulterations and 
 
 the retort, floating on the remains of the 
 
 water. 
 
 Sophifi cation of oil of lavender. 
 
 The oil of rofemary having a fcent, 
 which has fome affinity with that of laven- 
 der, as well as being like it. with refpeft to 
 colour and conliftence, and of a much lower 
 price, is frequently mixt with it. 
 
 This is of no great confequence, where 
 the oil of lavender is ufed as a medicine, 
 their nature being very much the fame - y but, 
 where the impofition may be thought of 
 moment with regard to the price, it may 
 be difcovered, if not in a very fmall degree, 
 by comparing a fpecimen of the genuine 
 oil with that which is fufpedted : when the 
 bitterifh and more oily fcent of the rofe- 
 mary will be a fufficient means of difcrimi- 
 nation to thofe who have an acute fmell. 
 
 Subftitutiom praSlifed with refpeB to rhubarb. 
 
 The rhapontic is very frequently fold, or 
 adminiftered, in the place of the true rhu- 
 barb - 7 
 
Substitutions. 371 
 
 barb ; to which it is fuppofed to be inferior 
 in its medicinal qualities. 
 
 The true rhubarb may be diftinguifhed 
 from the rhapontic, by thofe who are con- 
 vcrfant with drugs, by the grain and colour : 
 but the more obvious difference will be found 
 on chewing : when the rhapontic difTolves 
 quickly, by means of the faliva, into a muci- 
 lage of a very tinging yellow colour ; and 
 affords an earthy and much more difagreea- 
 ble flavour than the rhubarb. 
 
 There are two kinds of rhubarb at prefent 
 brought to England, the one is called the 
 Turky kind, which bears much the higheft 
 price, being in general of finer appearance $ 
 the other the Ruffian, but now more fre- 
 quently brought from China. As the latter 
 is commonly brought inthe private trade, by 
 the perfons employed in the fervice of the 
 India company, it is purchafed of them, in 
 large parcels, at a very low price, by thofe 
 who are in the fecret of this advantage ; and 
 by them forted into different kinds. The beft 
 pieces being picked out, and cut into a proper 
 form, and freed from all worm eaten, or other 
 depraved parts, is fold for Turky rhubarb ; 
 
 B b 2 and 
 
372 Adulterations and 
 and the next beft under forne other proper 
 denomination ; while the worm-eaten, or 
 other unfightly parts, are ufed for tin&ures 
 or fyrups : and, by this management, a very 
 confiderable profit is made. 
 
 Subjtitution for bezoar. 
 
 The oriental bezoar being of great price, 
 the gall ftones, found in the gall bladders of 
 oxen, are frequently fubftituted for it ; be- 
 ing of the fame nature : but, as even thefe 
 are fcarce, and not to be procured frequently, 
 the gall itfelfof oxen, or fheep, is moft ufually 
 put in its place. 
 
 It is net, however, of any moment, what 
 innocent fubftances are ufed in the place of 
 bezcar : the medicinal virtues of it being 
 imaginary ; and the drug itfelf now fo little 
 confidered, in any regular pradtice, that it 
 is excluded from the materia medica in the 
 laft edition of the college difpenfatory. 
 
 The true bezoar itfelf may be diftinguifh- 
 ed from the gall flones, or any artificial 
 compound, by its appearance only : but its 
 effeft may be eafily counterfeited, by feveral 
 
 means, 
 
Substitutions. 373 
 
 means, incompofitions where it is ufed, fuch 
 as the Goa flones, or Gafcoign's powder, fo as 
 not to be diftinguifhed ; whatfoever may have 
 been formerly thought to the contrary. The 
 effeft here fpoken of is the making teftaceous, 
 or other fuch like bodies, give a yellowifh 
 green colour to paper, when rubbed on it $ 
 which has been generally efteemed a certain 
 proof, that any compaction contained a due 
 proportion of bezoar. 
 
 They, therefore, who are defirous to have 
 thofe medicines genuine, in which thebezoar 
 has a part, muft prepare them themfelves j or, 
 otherwife, they can never be certain, that they 
 are not impofed upon in this particular. 
 
 Adulteration of gum-refins, gums, and balj ams, 
 in general. 
 The gum-refins, and gums, in general, 
 which make fo large and important a part 
 of the materia medica, are extremely liable 
 to fophiftications, by diffolving them, and, 
 in their reduction to a dry confidence, com- 
 mixing with them heterogeneous matter, ei- 
 ther refembling the gum -refins or gums them^ 
 felves, or fuch foulnefs as is natural to them 
 
 B b 3 from 
 
374 Adulterations and 
 from the manner of their production. But, 
 as this admits of a great variety of circum- 
 fiances, it is impracticable, to lay down any 
 particular rule, for the judging of, or prov- 
 ing, the purity, or genuinenefs, of fuch fab- 
 flances The eafieft method is, to compare 
 each kind with a well chofen fpecimen ; by 
 which, the degree of foulnefs from bodies 
 wholly heterogeneous, or alteration in the 
 apparent qualities by any fophifticating 
 mixture which has greater affinity with 
 them, will be beft perceived. 
 
 The purification, by folution in the proper 
 menftrua, may be, however, ufed, where it is 
 of great importance, to know, particularly, 
 the proportion of feculencies, that may be 
 contained in any parcel in queftion. 
 
 The balfam of capivi ; as alfo the Chio, 
 and Venice turpentines are very often fo- 
 phifticated with the common turpentine ; 
 and it is frequently fubftituted intirely in 
 their place, in compofitions. 
 
 The balm of Gilead, balfam of Peru, and 
 others of a dear kind, are, likewife, very fub- 
 je6t to be adulterated, by mixing turpen- 
 tine, 
 
Substitutions. 375 
 
 tine, or fome of the cheaper kinds, with the 
 dearer. 
 
 While they are alone, the feveral fpecies of 
 the terebinthinate genus are diftinguifhable 
 enough from each other : but, when they 
 are compounded with each other, or mixt 
 with bodies of a different nature, it is very 
 difficult to determine certainly with refpe6l 
 to the genuinenefs ; any further than can 
 be done, by their peculiar fcents ; to judge 
 the better of which, it is always proper to 
 have fpecimens of fuch as are known to be 
 good. 
 
 B b 4 IN- 
 
INDEX. 
 
 A. 
 
 ALCOHOL, p. 144: — compendious pre- 
 paration of, 1 45 
 
 jEthiops antimonialis, 28 : — mineral^ regular pro- 
 cefs for, 244 : quicker method of prepara- 
 tion of, 245 
 
 Alembic for the diftillation of quickfilver, 42 — • 
 — of vinegar, 43 — of volatile fpirits, 40 
 
 Alkaline salts, the/*/, famenefs of all, 66: — 
 the volatile famenefs of all, 70 
 
 Amber, procefs for the fait of, 20: — procefs tor 
 the oil of, 205 
 
 Anhalt water, 321 
 
 Antimony, butter of, 252: — diaphoretic^ 273: — 
 cinnabar of, regular procefs for, 252 : com- 
 mon procefs tor, 255 : improvement of the 
 
 common procefs for, 256: — crocus of, i6g : — 
 
 golden fu'phur of, 25 S : cheaper and more 
 
 compendious method of the preparation of, 
 266 : — regulus of, 258 : — martial regulus of, 
 
 262 : more profitable preparation of, 264 : 
 
 —ftellated regulus of, 266 : more com- 
 pendious method of preparation of, 268 
 
 a Apparatus 
 
INDEX. 
 
 Apparatus for aqua fortis, 47 : — for fpirit of 
 hartfhorn, 35 : — for oil of turpentine, 41 : — for 
 fpirit of fulphur by the bell, 48 : — for oil of 
 vitriol from fulphur, 44 : — for preparing tefta 
 cea, 34 
 
 AqiJjA fortis, 167 :— double, college procefs for, 
 
 1 69 : improved procefs for the preparation 
 
 of, 171 : method of converting pure fpirit of 
 
 nitre into, 176 :— Jingle, 167 method of 
 
 converting the pure fpirit of nitre into, 1 76 
 
 Arabic, gum, fubftitution for, 359 
 
 Arsenic, preparation of the yellow, 207 
 
 AURUM MOSAICUM 296 
 
 B. 
 
 Balsam of sulphur 341 : — common preparation 
 of, 342 
 
 Bark, volatile tin<5ture of, 341 
 
 Benjamin, the flowers of, 149 
 
 Bezoar, how counterfeited 372 : — mineral, 277 : — 
 — fhorter procefs for, 276 
 
 Bismuth, flowers of, 297 : — magiftery of, 299 
 
 Buckthorn berries, fubftitution for them, 366 
 
 C. 
 
 Calcination, 58 
 
 Calcined hartjhorn, 107: — vitriol, 154 
 
 Calomel, preparation of, 218 :— more expedite 
 method of preparation of, 220 : — how to detect 
 the adulterate, 223 
 
 Capillair, syrup of, 249 
 
 Camphor, refinement of, 151 :— — by fpirit of wine, 
 
 Caustic antimonial, 252 : — lunar, 288 ; im- 
 proved preparation of, 289 
 
 Ceruss, 
 
INDEX. 
 
 Ceruss, how adulterated, 354 
 Christallization, 63 : — inftruments of, 33 
 -Christals of tartar, \^\—oivtrdigrife, 302 
 Cinnabar of antimony* 252 : common pre- 
 paration of, 255 : improved preparation of, 
 
 256: — factitious, 246: improved prepara- 
 tion of, 248 : — native, how counterfeited, 353 
 Cinnamon, fubftitution for it, 358 : — the 0/7of, 
 
 367 : fubftitution for it, 367 : — water,Jimple, 
 
 367: by coftion^ 307: Spirituous, 3 09 
 
 Cloves, oil of, fubftitution for, 368 
 
 Confectio cardiaca, 33 1 : — improved prepara- 
 tion of, 334 
 Crabs eyes, fubftitution for them, 363 
 Crocus antimonij* 269: — metallorum* 271 
 Cream of tartar, 135 
 Cucurbits, 30 
 
 D. 
 
 Daffy's elixer, 348 
 
 Diaphoretic antimony, 273 
 
 Distillation, beft general methods of perform- 
 ing, 53 
 
 E. 
 
 Eaw d*Arqiiehuffade, 324 : — de Cannes, 322 : — 
 d'luce, 325 : improved preparation of, 327 
 
 Elixir, Daffy's, 348 : — acid of vitriol, 344:— — 
 — cheaper preparation of, 345 :—fweet of vitriol, 
 346 : — viganis of vitriol, 347 
 
 En s veneris, 29 1 : — improved preparation of, 293 
 
 Essence of lemons, fophiftication of, 369 
 
 Ethereal spirit* 14& 
 
 Fever 
 
INDEX. 
 
 F. 
 
 Fever powder, 285 
 
 Filtration, bed methods of performing, 59 
 Filters, 31 
 
 Flowers of Benjamin, 149 : — of bifmuth, 297:— 
 ofjieel, 291 
 
 Funnels for feparation of different fluids, 30 
 Furnaces, general obfervations on, 3 : — de- 
 fers of thofe at prefent in ufe, 6 : — iron work 
 neceflary for, 1 1 : — for the fand-pot and fand- 
 bath 14: — for the fublimation of mlomel, 24:— 
 for calcination, or the- wind furnace 26 : — for the 
 dijlillation of volatile fpirits, 3 6 
 
 Gascoign's powder, 336 : — cheaper preparation 
 of, 337 : — how counterfeited, 338 
 
 Goa stone, 339 : — how counterfeited, 34O 
 
 Greek Water, 287 
 
 Gum Arabic, fubftitution for, 359 
 
 * H. 
 
 Hartshorn, calcined, 107 : fictitious, 108 : — 
 
 volatile fait of, 104 : fictitious, 105 : — volatile 
 
 fpirit of, 85 : fictitious, but good, 93 : 
 
 fictitious and imperfeft, 97 : fophiftication 
 
 of, 99 : common method for detecting the 
 
 fophifticate, -ioo: more certain method of 
 
 detecting the fophifticate, 103 
 
 Honey water, the king's, 318:— fictitious, but 
 good, 320 
 
 Hungary water, 315:— cheap and extempora- 
 neous preparation of, 316 
 
 Kermes 
 
INDEX. 
 
 K. 
 
 Kermes mineral 281 :— more profitable prepara- 
 tion of, 28 j 
 
 Lac fulphuris, 197 : — improved procefs for, 197 : 
 
 — fophiftication of, 91 : — — how detr&ed, 200 
 
 Lavender, preparation of thefitnple fpirit of, 310: 
 
 — ■ extemporaneous and cheaper preparation 
 
 of, 311 : — compound fpir /t o.% 3 1 1 : extem- 
 poraneous and cheaper preparation of, 3x3 
 Lead, white, how adulterated, 354: — red, how 
 adulterated, ^55 
 Levigation, 62 •, — improved apparatus for, 34 
 Lunar caustic, 2h8 
 Lutes, ■ 49 
 
 M. 
 
 Magistery of bifmuth, 299 
 
 Magnesia alba, 191 : — fi&ititious, 19 ^ 
 
 Mercury, red precipitate of, 233 :— improved 
 
 procefs for, 236: manner of- dete&ing rhe a- 
 
 dulteration, 238: — wbiteprerpitateaf, 22 5 : 
 
 improved procefs for, 228 : — • - manner of de- 
 tecting the adulterations of, 23 1 . — corrofwefuhli- 
 maie of, 210: — —improved procefs for, 213 : — ■ 
 — method of detefting the adulterations of , 2 1 7 : 
 
 precipita'e pcrfc, 243: — purification of, 2 o 8 : 
 
 more expedite method of, 209 : — yellow emetic 
 of, or turpeth mineral, 239: improved pro- 
 cefs for, 242 
 Minium, how adulterated, 355 
 
 Native 
 
INDEX. 
 
 N. 
 
 Native cinnabar, fubftitution for, 353 
 
 Nitre spirit of, 164:- — improved procefs for the 
 
 pure, j 73 :<— -method of proving and purifying, 
 
 174: — converfion of the pure into fingle aqua 
 
 fords, * 76 : into double aqua fortis, 177: — 
 
 dulcified, 178 
 
 O. 
 
 Oil of amber * 205 : — cinnamon* fubftitution for, 
 367 : — clones, fubftitution for it, 368 : — lavender* 
 fophiftication ot it, 368 : — tartar per deliquium, 
 
 ♦ 129 : extemporaneous preparation of, 130 : 
 
 — turpentine* 143 : — vitriol* 156 : prepara- 
 tion of, from fulphur, 158 
 
 i 
 
 P. 
 
 Pearl ashes, fubftitution for, 362 
 
 Powder, fever, 285 
 
 Pearls, fubftitution for, 363 
 
 Precipitate, per fe* 243 : — red* of mercury, 
 233 : — —-improved procefs for, 236 :— - — man- 
 ner ot detecting the adulterations of, 238 : — 
 
 white* of mercury, 225: improved procefs 
 
 for, 228: —manner of deteding the adultera- 
 tions of, 231 
 
 Quicksilver, adulteration of, 235 : — purification 
 of, 208 : — more expedite method of purification 
 of, 209 
 
 4 Receivers, 
 
INDEX. 
 
 R. 
 
 Receivers 28 
 
 Red lead, adulteration of, 355 
 
 Regulus of antimony, 278: — with fteel, or mar- 
 tial ngulus* 262 ;— — more profitable prepara- 
 tion of, 264:— -Jlellated) preparation of, 266: — 
 -—improved procefs for, 268 
 
 Resin, 143 
 
 Retorts, 28 
 
 Rhubarb, fubftitution for, and management 
 of, 370 
 
 Rosemary, — fpirit of, or Hungary water, 315 : — 
 — cheap and extemporaneous preparation of, 316 
 
 Saffron, how adulterated, 3^1 
 Sal ammoniacum, volatile fait of, 108 : im- 
 proved procefs for, 109 : prepared with 
 
 fixt alkaline fait, 112 : cheaper pre- 
 paration of, 113 : — volatile fpirit of with quick- 
 lime, 115: improved procefs for, 116: 
 
 — dulcified fpirit of, 118 : — — — extem- 
 poraneous, 1:9 : — mirabile Glauberi, 184: — 
 — improved procefs for, 187 : — — prepara- 
 tion of the counterfeit kind of, or Lymington 
 
 fait, 189: method of diftinguifhing the 
 
 counterfeit kind from the true, 190 :—polycbreJl 9 
 
 182 : — prunell<e, 179 : preparation of it 
 
 from the fal enixum, 181 : — volatile oleofum, 
 
 j , £ : cheaper preparation of, 121 : * 
 
 fophiftication of, how dete&ed, 122 
 
 Salt of amber, 204: — volatile of hartfhorn, 104 : — 
 
 — of fal ammoniacum, 108 : —oijleel, 290 : — 
 
 — prepared from green vitriol, 290 : — of tartar, 
 
 126: 
 
I N D E X. 
 
 126: — *— fi&itious, 127 : — of wormwood* 123: 
 
 ■ fictitious, 125 
 
 Sameness of the calcined earths of all animal and 
 vegetable fubftances, 77 : — of the burnt oils of 
 all vegetables, 76 i — of oils diftilled from all 
 kinds and parts of animals, 94 : — of all fixt al- 
 kaline lalts, 76:— of ail volatile alkaline falts 72 : 
 — of the acid fpirit obtained from fulphur, vitriol, 
 fal catharticum and alum, 80 : — of vitriol ate tar- 
 tar, fal polychreftum, fal prunellas and fal enixum, 
 8 1 : — of all vinous fpirits, 79 
 
 SELLE deSEIGNETTE, 132 
 
 Separating funnels, 30 
 
 Sperm a coeti, how counterfeited, 357 
 
 Spirit, ethereal* 148 : — of hartfhorn, 85 : — of 
 
 lavender, fimple, 310: compound, 3 1 2 : — of 
 
 nitre* 164 : — volatile of hart/horn, 85 : — volatile 
 of fal ammoniacum* 1 1 5 : — dulcified of fal ammo- 
 
 niacum* 1 1 8 : of nitre, 178 : of vitriol, 
 
 163 : — of fulphur by the bell, 194: — of turpen- 
 tine* fee oil, 143 : — of vitriol* 1 3 7 :—re£lified of 
 wine, 144 
 
 Spir itus falls ammoniaci dulcis* 1 1 8 : — dulcis niiri, 
 178 : — dulcis vitriolic 163 : — volatilis aromati- 
 cus* 1 1 9 
 
 Steel, flowers of, 291 : — fait of, 299 
 
 Sublimation, general method of performing, 57 
 Sulphur, auratum antimonij* 258 : — balfam of* 
 341 :— fpirit of, by the bell, 194 
 
 Syrup of capillair, - 349 
 
 T. 
 
 Tartar oil of per deliquium* 129: — cream* or cry- 
 
 Jials of, 134 \—faltoi* i26:—fo!ubk* ijo : 
 
 extern- 
 
m 
 
 INDEX. 
 
 extemporaneous, 131: — vitriolated, 137: 
 
 ■prepared from the fal enixum, 1^9 
 
 TkstacaA, fubftitution for them, 364 
 
 Xincture, volatile of the bark, 341 
 
 Tritorium, 30 
 
 TlJRPENlNE, OIL of, I43 
 
 TURPETH MINERAL, 239 
 
 
 #v. 
 
 Vermilion, 248 
 
 VERDIGRISE, DISTILLED, Or CHRYSTALS of, 302 
 
 Vjnegar, adulteration of, 359 : — common method 
 
 of diftillation of, 140 :~ improved method, 
 
 142 : — fophiftication how dete&ed, 141 
 
 Vitriol, calcined, 154 :~oil of, 156 : — Roman 
 faElttious, 304 
 
 Vitriolated tartar, I3f 
 
 W 
 
 Water, Anbalt, 321 : — cinnamon^ 307: — Hun- 
 gary, 315 : — king** honey , 3 1 8 
 Wine, rectified fpirit of, H4 
 


 V 
 
 * 
 

 /Zo&S&Vf.