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 : 
 
 CHEMICAL 
 
 LECTURES, 
 
 Publickly Read at London, 
 
 In the Years 1731, and 1732; 
 
 •And at Scarborough, in 1733; 
 
 % 
 
 For the Improvement of 
 
 \ 
 
 ARTS, TRADES, 
 
 AND 
 
 1 
 
 NATURAL PHILOSOPHY. 
 
 By PETER SHAW, M. D. F. R. S. 
 Fellow of the Royal College of Phyficians in London, 
 Andoneof His Majesty’s Phyficians in Ordinary. 
 
 The Second Edition, Corredted. 
 
 LONDON: 
 
 Printed for T. and T. L on g m a n, in pater Nojier 
 Row *, J. S H u c K B u R G H, in Fleet-Street ; and 
 A. M I L L A R, in the Strand, 
 
 MDCCLV. 
 
Digitized by the Internet Archive 
 in 2016 
 
 I 
 
 https://archive.org/details/chemicallecturesOOshaw 
 
C iii } 
 
 TO THE 
 R-ight Honourable the 
 
 Lord Vifcount Lonfdale^ 
 
 Lord PRivy-SEiiL, ^c. 
 
 My Lord, 
 
 \ S your Lordfhip was pleafed to ho- 
 ^ nour thefe Ledlures with your No- 
 tice in Manufcript, I take the Liberty of 
 laying them before you in Print ; being 
 dehrous the Publick fhould know, that 
 their Deiign was approved of by fo un- 
 exceptionable a Judge. 
 
 a 2 
 
 For, 
 
■ iv DEDICATION. 
 
 Fcr, beiides your uncommon Skill in 
 Civil Policy, the Laws, and all the 
 Branches of Publick Buhnefs ; you have, 
 like the Illulirious Lord Bacon, a Talent 
 for the Improvement ot Arts, and a 
 Pleaftire, and Sagacity, in purfuing na- 
 tural Enquiries, 
 
 Were I not, therefore, fenfible, my 
 Lord, that your Candour is as extenfive 
 as your Learning, I fhould be cautious 
 of thus fubmitting thefe Bender Enqui- 
 ries to your View ; as they are neither 
 condudled dn a Manner fuitable to your 
 corredl and exquifite Tafle; nor purfued 
 to fuch a Length, as your great Knov/- 
 
 ledge in Phiiofophical Matters may jufliy 
 require. 
 
 But this gives me farther Encourage- 
 ment, that 1 do not know a more ufe- 
 
 ful 
 
DEDICATION. 
 
 V 
 
 ful Subject, than the prefent, to a Tra- 
 ding Nation; nor a Perfon better quali- 
 fied than your Lordfhip, to perceive its 
 Tendency, and diredt its Improvement. 
 
 I am 
 
 MY LORD, 
 
 Your Lordship’s 
 
 Scarborough, 
 July 15. 1733- 
 
 Mojl obliged^ and demoted kumble 
 Servant, 
 
 Peter Sh^w. 
 
ADVERTISEMENT. 
 
 T H E following LeBures had the 
 Honour to be read before a noble 
 Audience^ who candidly overlooked their 
 Failings., and requefled their Publi- 
 catio7i. 
 
 As the Defgn is of large Extent, 
 little more than a Sample of the whole 
 could at prefent be given ; the far- 
 ther Improvement of it being left to 
 others. 
 
 Ehe Experhnents here en7ployed, thd 
 many of them new, are generally frmple ; 
 or performable with little Cofi, and Ap- 
 paratus : But if a few particzdar In- 
 fruments, a fid ‘Trials, hereafter 'inti- 
 mated, were to be made, and properly 
 ufed, much greater Difcoveries might be 
 reafonably expeBed. 
 
[ vH] 
 
 G L O S S A R Y: 
 
 O R 
 
 Explanation of .the Technical 
 Terms in this Work. 
 
 A dd. By Acids are meant all'thofe Things 
 that tafteTour *, as Vinegar, Tartar, Juice 
 offCrabs, Lemons, Spirit of Nitre, Spirit 
 of Salt, and which, when mixed with a due 
 Proportion of an Alkali^ conftitute a neutral 
 Body, wherein neither Acid nor Alkali pre- 
 vails *, whence it alters not the Colour of Sy- 
 rup of Violets. See Alkali and Neutrals. 
 Adits, See Burrows. 
 
 Alcohol. Is, pure and perfect Spirit of Wine, with- 
 out the leail Particle of Water, or Phlegm. 
 Alkali. Is a Word of extenfive Signification, and 
 chemically denotes a large Tribe of Bodies. 
 For all Bodies may be chemically confidered 
 under three Tribes •, or as being either Alkalies., 
 Acids.,‘ or Neutrals. Alkalies have this efiTential 
 Property, - that when mixed, or united, with 
 Acids., they conftitute Neutrals. But a more 
 common Mark of an Alkali is, that it turns 
 Syrup of Wiolets green, as an Acid turns it red ; 
 w'hilft the Admixture of a Neutral Body does 
 a 4 not 
 
vni 
 
 A GLOSSARY. 
 
 not alter the Colour of that Syrup. Thus Pot- 
 Afh, Salt of Tartar, and all fixed vegetable 
 Salts ; as likevvife all volatile animal Salts and 
 Spirits, arc artificial Alkalies'^ as Chalk, the 
 teftaceous Bodies, are natural Alkalies, 
 
 And thus, in the vegetable Kingdom, Onions, 
 Leeks, Garlick, Muflard, Cfr. are Alkaline \ 
 as Sorrel, Wood-Sorrel, the Juice of Lemons, 
 Oranges, Verjuice, are Acid, Their Dif- 
 ference alfo is manifefl from the Tafte, when 
 the Habit of thus diftinguifhing them is ac- 
 quired. Acids Neutrals. 
 
 Amclgamaticn. is the Difiblution, or Mixture of 
 any Metal with Quickfilver : But Iron, of all 
 the Metals, v/ill not amalgamate, or unite 
 therewith. 
 
 AJfaying. Is the Art of difeovering how much 
 pure Metal is contained in any Ore, or Coin, 
 afiigned. Hence to make an EJfay,^ is to pro- 
 duce a Lump, or Grain, of pure Metal, from 
 any fmall Quantity of Ore, or Coin. 
 
 Axioms, By Axioms are meant a Kind of Corol- 
 laries, Confequences, orRefults, of certain Ex- 
 periments, Fadts, Obfervations, or particular 
 Dodlrines ; fo as to recapitulate a certain ufe- 
 ful T ruth, contained in the preceding Partof the 
 Work, and fee it in a clearer Light, with re- 
 gard to Theory, or Speculation •, As Canons, 
 or Rules, regard Experience or Pradfice. See 
 Canons 
 
 . Balneum Mari^. Or W ater-Heat, is no more than 
 a Velfel of Water, fet in a Furnace, or over 
 the Fire, with another Vcfiel put into the Wa- 
 ter *, which latter Veffel contains the Matter, 
 or Subjedl, ol the Operation. 
 
 Buddling Dtfljes. Are flaallow Dilhes, like the 
 Balbns oi a Fair of Scales, for the wafhing of 
 , Ores by the Fiand. 
 
 Burrows, 
 
IX 
 
 A GLOSSARY. 
 
 Burrows, In Mining, are the Paflages leading 
 into a Mine, and cut thro’ the Sides of a Hill, 
 or Mountain, fo large that the Workmen may 
 conveniently wheel out the Ore in Barrows, or 
 carry it along in Bafl^ets. 
 
 Calcination. Is the burning of a Body in an open 
 Fire, in order to difcharge its more volatile 
 Parts, or reduce it to Powder, 
 
 Canons. Are Rules of Pradice, or Diredlions, 
 for producing Effeds, or performing Ope- 
 rations ; and have the fame Regard to Pradice, 
 as Axioms have to Theory. See Axioms. 
 
 Caput Mortuum, Is that Part of the Matter, 
 which remains behind after Dillillation, or 
 Sublimation. 
 
 Cementation. Is the clofe burning of a hard or 
 metalline Body, with certain opening Powders, 
 flrew’d betwixt its groffer Parts *, fo as to foften, 
 tinge, or impregnate them, with the PTmes 
 of fuch Powders ; or it is the Introdudion 
 of any Mineral, or Metallic Fumes into the 
 folid Plates of a Metal, by Means of a proper 
 Fleat, applied to a clofe Veflcl, or double 
 Crucible, wherein the Plates are laid, with the 
 pulverized Matter ftrew’d between them. 
 
 Clarification. See Depuration. 
 
 Concentrating, Is bringing the required Parts 
 of a Subjed clofer together; as Salt-Water 
 is concentrated by evaporating the aqueous 
 Humidity ; and Wine by freezing out, or fe- 
 parating its Water, in the Form ol Ice. 
 
 Copelling^ or Cupelling. Is putting metallic Mat- 
 ters upon a cover’d VelTel of Bone-Afhes in a 
 naked Fire, to try v^hat Gold or Silver they 
 will afford. 
 
 Cryftallization. Is the Operation, whereby Salts 
 dilTolved in Water fhoot into Glebes, of par- 
 ticular 
 
X 
 
 A GLOSSARY. 
 
 ticular Figures, according to the Nature of 
 each Salt. 
 
 Decantation, Is the pouring off a clearer Liquor 
 from a groffer Sediment, after ftanding. 
 
 Defiagration. Is fetting explofive Matters on Fire 
 in a Crucible, or other Veffel, and fuffering 
 
 ' them to burn out ; as when Nitre, or Tartar, 
 are thrown into a red hot Crucible, or to any 
 melted Matter, whilfl it continues in the Fire. 
 
 Depuration. Is the making of any Matter pure, 
 of freeing it from the Drofs, Dirt, or other 
 heterogeneous Parts, wherewith it may happen 
 to be mixed : So Honey is depurated, or cla- 
 rified, by heating it, and taking off the Scum 
 that rifes to the Top. 
 
 Bigeftion. Is fuffering folid and liquid, or groffer 
 and finer Matters, to ftand together in a gentle ' 
 Heat for fome Time, that the Liquor may ex- 
 traifl the Virtues of the folid Ingredients; or 
 the whole become more fubtile and uniform, 
 
 Diftillation. -Is the raifing of Liquids into Vapour 
 by Heat ; and condenfing that Vapour into a 
 Liquid again. 
 
 Elicofaccharum. Is an intimate Mixture of any 
 effential Oil, with Sugar ; by grinding them 
 together in a Mortar. 
 
 Elements. See Principles. 
 
 Elixation. Is the walking a Matter with Water, 
 in order to get out what will diffoive therein. 
 
 ' Emfyreuma. Is a naufeous Tafte, or Odour, 
 proceeding from the Subject being fcorched, 
 or over heated, in the Operation ; as when 
 Milk is burnt to, as they call it. 
 
 Ejjential., or Chemical Oils. Are the native Oils 
 of Vegetables, drawn from them by Diftii- 
 latlon with Water. 
 
 Evaporation. 
 
XI 
 
 A GLOSSARY. 
 
 "Evaporation. Is the fetting a Liquor in a gentle 
 Heat, to difcharge its fuperfluous Humidity, 
 or obtain its dry Remainder. 
 
 Faints. Are the Liquor that runs from the Still, 
 upon diftilling any inflammable Spirit, after 
 all the Proof-Spirit is come over. See Proof. 
 
 Filtration. Is fuflering any Liquor to pafs thro’ 
 Cap- Paper, or rather a peculiar Kind of filtring 
 Paper, into a clean VeflTel, or Glafs ; the Paper 
 being cut conically for the Purpofe, and put 
 into a Glafs Funnel, or laid upon a Stone Co- 
 lander, or Strainer. 
 
 Form. Is the particular A6 lT. or Law of Nature, 
 whereby a Thing' is produced. 
 
 Flux. Is any Matter added to an. Ore, or me- 
 tallic Matter, in order to make it melt, or run 
 the eafier, and yield a greater Quantity, or a 
 purer Metal. 
 
 Fiilmination. Is the fame as Deflagration^ which 
 
 feL 
 
 Fufing. Is the fame as Melting, being a Term 
 generally applied to the melting of Metals, and 
 metallic Matters, with a ftrong Heat. 
 
 Inflation. Is fuffering Matters to fland and di- 
 gefl: in the Heat of the Sun, inftead of ufing 
 the Heat of a Furnace. 
 
 or Laque. Is a Kind of Extrafl, or thick 
 Body of Colour, prepared chiefly from vege- 
 table Subjefls, for Painters Ufe. Of thefe 
 Laques there are feveral Sorts ; but in a more 
 particular Senfe, it fignifies the 'Red Laque ob- 
 tained by boiling Stick-Lac in Water. 
 
 Lavaderos. In Mining, are the Houfes, or lar^e 
 Troughs,' where the Ore is walked. 
 
 Limation. Is the filing of a Metal, or metallic 
 Subllance, fo as to reduce it into fmall Parts, 
 called-the Tilings of that Metal. 
 
 Lixivium. 
 
XU 
 
 A GLOSSARY. 
 
 Lixivium. Is the fame Thing as Lee, or a So- 
 lution of Salts, by boiling any faline Matter in 
 Water. 
 
 Load. In Mining, is the fame as Ore. 
 
 Lotion. Is the wafliing of a Body in Water, to 
 get out its Salt, or whatever elfe will diffolve 
 in Water. 
 
 Low-Wines. Are a weak Spirit, or the firft 
 Runnings of the Still, in diftilling Brandies or 
 Spirits, from W^afh or "Wines, and mixed along 
 with the fecond Running, or more watry Part. 
 
 Meyifiruum. Is any Body applied to another, fo 
 as to diffolve it, and intimately mix its Parts 
 with the Parts of the other : in which Refpeft 
 the former may be called the Solvent^ and the 
 latter the Solvend. 
 
 Mercury. Is another Name for ^ickfiher. 
 
 Metallurgy. Includes the whole Art of working 
 Metals from the Ore to faleable Metal. 
 
 Muffle. Is an arched earthen Inftrument made 
 to cover a Tell, in Cupelling, fo as that the 
 Coals, or Affies of the Fire, may not fall in 
 upon the Subjeft. See Cupelling. 
 
 Mujt. Is the unfermented Juice of the Grape ; 
 or any other liquid fermentable Subftance, be- 
 fore it enters the A6l ot Fermentation. See 
 Stum. 
 
 LJeutrals^i or Neutral Bodies. Are fuch Bodies as 
 manifeft no Signs of either Alkali., or Add., 
 upon any of the Trials known, and allowed 
 to difcover them •, as particularly not by the 
 Tafte, or the Admixture of Syrup of Violets, 
 kAc. See Acid and Alkali. 
 
 Bcr Leliquium. Is the running of diffolvable 
 Things into Liquor, by barely expofing them 
 to the open Air, or to the moift Air of a Cellar. 
 
 Phlegm. Is the fame as Water, or aqueous Li- 
 quor. 
 
 Pre- 
 
A GLOSSARY. 
 
 Precipitation. Is the depofiting of a Sediment; 
 either by a Liquor {landing at Reft, or when 
 any Addition is ufcd for the Purpofe. 
 
 Principles. Are the different fimple Matters, 
 whereof a Body is compofed. 
 
 Proof. In Spirits is meant of a certain Trial, or 
 Way of examining their Strength, by the Bub- 
 bles that arife on their Surface Uj-on fhaking 
 them in a Phial. 
 
 ^iartation. Is the Separating of Gold from Sil- 
 ver, by Means of Aqua- Forth or Aqua- Regia. 
 
 ^intejjmce Is the Mixture of an eftential Oil 
 with Alcohol. 
 
 ReAification. Is purifying a Subject, by repeat- 
 ing the Operations ; as Brandy is purified, or 
 feparated, from its Phlegm, by repeated Di- 
 ftillation. 
 
 ReduEiion. Is the reducing.^ or recovering a Metal 
 from its Calx., or Afhes \ and may likewife be 
 applied, when any Body deftroyed, as to its 
 natural Form, or Appearance, is made to af- 
 fume that Form again. 
 
 Refrigeratory. Is a VeiTel of cold Water, thro’ 
 which a winding metalline Pipe takes its 
 Courfe, from the Plot Still, fo as to bring off 
 the Liquor cool, by Diftillation. 
 
 Regulus. Is an impure, or imperfedt metallic 
 Subftance, that falls to the Bottom of the Cru- 
 cible in die melting of Ores, or impure metal- 
 lic Subftances. 
 
 Scoria. See Slag 
 
 Separating-Glafs. Is a bellied Glafs, open at top, 
 and ending in a hollow Stem below •, fo that a 
 Mixture of Oil and Water being put therein, 
 and fuffered to reft till they feparate, the 
 W ater may be poured off from the Oil. 
 
XlV 
 
 A GLOSSARY. 
 
 ^lag. Is the Drofs, Cruft, or Scoria^ found at 
 the Top of a melted Metal, or metallic Mat- 
 ter ; being often in the Form of a vitrified 
 Mafs, or Giafty Subftance, and proceeding 
 from the Flux employed, and united with fomc 
 ftony recrementitious Matter contained in the 
 Ore. But when a large Proportion of a faline 
 Flux is ufed, the Slag will relent, or even diF 
 folve in the Air. 
 
 Solvent, See Menftruum. 
 
 Stum. Is Mujiy clarified by ftanding and racking, 
 then put up into matched Cafks, that is. Calks 
 impregnated with the Fume of burning Brim- 
 ftone, fo as to be preferved found in an unfer- 
 mented State. See Muft. 
 
 Sublimation. Is the raifing of a dry Body by Heat 
 into Flowers, or a foiid Cake, at the Top ot 
 the containing Veflel \ being a Kind of Diftil- 
 lation fuited to dry Bodies. 
 
 Suhfidence. Is the fuffering a Liquor to fettle, 
 and fine itfelf, by ftanding. 
 
 Sulphur, Is another Name for Brimftone *, but 
 in a more Technical Senle, denotes the fat, un- 
 (ftuoLis, or oily Principle in Bodies \ or that 
 Part of them, which is truly inflammable. 
 
 ^hc'nnometer . Is an Inftrument contrived to mea- 
 fure the Degrees of Heat. Thofe made with 
 Spirit of Wine, ferve for the lefTer Degrees, 
 and thofe with Oil, or Quickfilver, for the 
 greater. 
 
 I’riture. Is the grinding, or rubbing any foiid 
 Body to Powder in a Mortar, or upon a grind- 
 ing, or levigating Stone. 
 
 ^orrefadlicn. Is the roafting, or fcorching, of a 
 Body by the Fire, in order to difeharge a Part 
 cither unneceffary or hurtful, in another Ope- 
 ration, 
 
A GLOSSARY. 
 
 ration ; as Sulphur is difcharged from an Ore, 
 before the Metal can be obtained to advantage. 
 
 'Turnfol. Is a red Colour prepared from the Juice 
 of the Sun-Flower, and fermented Urine : 
 which Colour being, in a fluid State, drank up 
 by Linen-Rags, and dried, is the Thing fold 
 by the Dry-Salters to the Dyers and the Wine- 
 Coopers, for dying Cloths, and tinging Wines 
 red. 
 
 Vitrification. Is the turning of a Body to Glafs 
 in the Fire. 
 
 Wajh. Is the fame Thing as fermented Wort, 
 or any fermented Liquor, fitted/to afford an 
 inflammable Spirit, or Brandy, by Diftillation. 
 
 x\r' 
 
 TABLE 
 
[ xvi ] 
 
 Table of C ON T E N T S. 
 
 L E C T. I. 
 
 Of Philosophical Chemistry. 
 
 I . \ ^ Account of the Office and QhjeEis of 
 
 Chemiftry Page i-6 
 
 2 'The chemical Treatment of Bodies 7-20 
 
 3 Rules for making new Dif cover ies 20, 21 
 
 4 The Deftgny and Manner of Execution i, 2 
 
 5 Philofophical Chemiftry defined i 
 
 6 The Objects of Chemiftry claffied 2 • 
 
 7 Bodies bow to be divided 
 
 8 General Structure of the Earth 
 
 9 Earthy in particular^ analyfed 6, 7 
 
 10 The Black Flux 8 
 
 11 Ores how analyfed B, 9 
 
 12 JVater divided^ and analyfed 9, 10 
 
 13 The Atmofphere divided^ and Air analyfed 10,1 1 
 
 14 Inftrmnents of Chemiftry 1 1, 14 ^ 
 
 15 The pbyfical Agents of Nature ibid. 
 
 1 6 The Kinds of chemical Oivifion 1 5 
 
 17 Fluickfilver fuhtilely divided ibid. 
 
 1 8 Brandy analyfed 1 6 
 
 19 Aggregates and Mix ts explained ibid. 
 
 20 Senfible Bodies compofed of infenfible ibid. 
 
 2 1 Recompofition illuftrated 1 7 
 
 22 ^ickftiver recovered ibid. 
 
 23 Relations^ and Changes ^ of Bodies 18 
 
 24 The Refolutions^ and Mixtures of Chemiftry ib. 
 
 25 The Produbiions of Mixture ibid. 
 
 z 6 The phyfical Caufes of chemical Effebls 19 
 
 2 7 AJ- 
 
 
XVll 
 
 Table of C O’ N T E N T S. 
 
 2 7 Advantages of improving Chemijiry 1 9 
 
 28 T' he general Subjects of all the Lebiures ibid. 
 
 29 Rules for condutling Philofophical Chemijiry 20> 
 
 2 I 
 
 3 o Axioms and Canons of the LeBure 22-24 
 
 L E C T. U. 
 
 Of Fire. 
 
 1 Fire, 'what 25-27 
 
 2 Fluids expand with Heat 2 7 
 
 3 Fhree Species of Fire 28, 2^ 
 
 4 Fuel, what 29-31 
 
 5 Air necejfary to Fire 3 1 
 
 6 Air fpoiled by Fire 3 2 
 
 7 Fuel, how charred 33 
 
 8 fuperficial ibid. 
 
 9 Fhe Effects of Fire 34 
 
 10 Fhe Kinds of Heat 3 5 
 
 11 Fhe Degrees'" of Purity in Fires ibid. 
 
 1-2 The Degrees of Heat 36-38 
 
 13 Axioms and Canons 3S-41 
 
 L E C T. III. 
 
 Of Air. 
 
 1 Fhe Atmofphere what, and how to he examined 42 
 
 2 Receives Vapours 43, 44 
 
 3 Fhe AiPs Prejfure and Elafticity 44, 45 
 
 4 Nature and EffeFis of the Atmofphers 46 
 
 5 thermometers explained, ibid. 
 
 6 Water in Air ^ 47 ? 4^ 
 
 7 Frejh^ Air required in Refpiration 48, 49 
 
 8 Air in Liquors • 49? 50 
 
 9 How far Air promotes Solutions 
 
 I o Air in Solids ^ ^ 5 5 2 
 
 I I Axioms and Canons 53 - 58 - 
 
 a a LECT. 
 
xvni 
 
 Table of CONTENTS. 
 
 L E C T. IV. 
 
 Of Earth. 
 
 1 ^he Species of Earths 59'^5j 7i 
 
 2 Mould analyfed by Water 60-63 
 
 3 By Fire 63 
 
 4 into Clay 64 
 
 5 Pottery^ &c. improve able 65 
 
 6 Ffuicklime deprived of its Salt 66 
 
 7 Marcafites^ what 6y^ 6S 
 
 8 Mundick analyfed 6^^ 6g 
 
 9 Alab after calcined ^9? 70 
 
 10 reduced to two general Kinds 71 
 
 1 1 Axioms and Canons 7 1 - 74 
 
 L E C T. V. 
 
 Of Water. 
 
 1 Water defined 75 
 
 2 Found in dry Bodies^ and the dry eft Air 75-77 
 
 3 Contains Earth 79 
 
 4 Its Properties^ Office, and life 80 
 
 5 Which the moft fertilizing 8 1 
 
 6 Its diffiolving Power ibid. 
 
 ' 7 Its Contents ^3, 84 
 
 8 Common Water ex amhi d 85, 86 
 
 9 Mineral Waters ex aminA 87-89 
 
 10 Pyxmont. Water imitated ' 90, 91 
 
 IT Axioms and Canons 9 ^ - 94 - 
 
 L E C T. VI. 
 
 Of Menstruum Sr 
 
 1 Menftruums what ' 95 ^ 9 ^ 
 
 2 Fhe Menftruums of Nature 96 
 
 3 Fhe Powers of Water as a Menftruum 97-99 
 
 4 The 
 
XiX 
 
 Table of CONTENTS, 
 
 ne dijfohing Power of A\co\\o\ lOO 102 
 
 PLe difolving Power of Oil 102, 103 
 
 Phe Relation betwixt Oils and Metals 103, 104 
 
 Bread difiilled 104, 105 
 
 Lead atnalgamated 105? 
 
 9 Gold and Silver difj oh ed 107, 108 
 
 10 Aqua- fords, and Aqua-Regia, how 
 
 made 108 
 
 11 Ufes of the Solution of Silver 108, 109 
 
 1 2 Silver^ how recoverable after Solution 1 09 
 
 13 Ufes of the Solution of Gold ibid. 
 
 14 The Digeftcr explained 110 
 
 15 Bone J opened by it "ibid. 
 
 1 6 Axioms and Canons 1 1 1 - 1 1 6 
 
 L E C T. VII. 
 
 Cf Fermentation and Putrefaction. 
 I Phe Nature^ Ofice^ and Ufe of Fermentation 
 
 and Putrefadiion 117, &c. 
 
 2 PFine-t how made 118-124 
 
 3 Vinegar^ how made 124-127 
 
 4 Vappidity and PutrefadHon fucceed Fermenta- 
 
 tion 128-130 
 
 5 Phe Changes produced by Fermentation 1 30, 1 3 1 
 
 6 Inflammable Spirit^ how procured 1 3 1 
 
 7 Proof in Spirits^ what 132 
 
 8 Sphdt of Wine y how obtained ibid. 
 
 9 Its Ufes 133 
 
 I o Vinegar yields no Alcohol ibid. 
 
 II Piitrefadiion^ in Vegetables^ what 134 
 
 1 2 Its Ufe in Prade^ and in the animal 0 economy 
 
 J 35 > *36 
 
 1 3 Animal Putrefadiion^ what 1 3 6 
 
 1 4 Fermentation determined 137 
 
 j 5 Phe Chemiftry of Nature in Bodies 138 
 
 a a 2 16 Mi- 
 
 t 
 

 16 
 
 17 
 
 Table of C O N T E N T S. 
 
 Mineral I’ermentaiiGn^ what 138 , 139 
 
 Axioms and Canons ^ 1 40 - 1 44 
 
 L E C T. VIII. 
 
 Cf Analytical Chemistry. 
 
 I Principle in Chemftry\ what 
 
 145 
 
 2 Wormwood analy fed 
 
 148-154 
 
 3 Bone analyfed 
 
 154 156 
 
 4 animal Principles purified 
 
 156-158 
 
 5 Cinnabar analyfed 
 
 J59-162 
 
 6 Refult of the Analyfis of Minerals 
 
 162 
 
 y Axioms and Canons 
 
 162- 1 67 
 
 L E C T. IX. 
 
 Of Synthetical Chemistry. 
 
 1 Synthetical Cbemijlry^ what 168, 169 
 
 2 Mitre analyjed and recompofed 1 69 • 1 70 
 
 3 Brandy analy fed and re compofed 172, 17 3- 
 
 4 Cinnabar recompofed 174-176 
 
 Bone recompofed 176-177 
 
 Perfect and imperfect Recompcfdion 179 
 
 y Axioms and Canons 1 80-18^ 
 
 L E C T. X. 
 
 Cf Vegetable Curation. 
 
 1 Vegetable Curation^ what 184, 185 
 
 2 T'he Prcccfs of Malting 1 8 5 - 1 8 7 
 
 3 Malting improve able 1 8 7 - 1 9 1 
 
 4 Vegetable Juu es how cured ^ 9 ^ * 93 
 
 3 Wort infpijfated ^ 93*^95 
 
 6 IP aft cured and preferved 195, 196 
 
 7 PerfeV Curation^ what 196, T9 7 
 
 ^ Axioms and Canons ^ 97 “ ^99 
 
 L E C T. 
 

 Table of CONTENTS. 
 
 XXI 
 
 : LEG T. XL 
 
 Of Wines and Spirits 
 
 1 Artificial Muft prepared 
 
 2 Sweets what , 
 
 3 "Tbeir Ufes 
 
 4 JVines how fined 
 
 ^ ^beir Difeafes^ how cured 
 
 6 V/hite IFines, how tinged red 
 
 7 Wines concentrated by Frojl 
 
 8 Prick'd Wines^ how recover'd 
 
 9 Brewing for DiftillaHon 
 }o Axioms and Canons 
 
 Appendix. 
 
 11 Phe T'heory of vinous Fermentation 
 
 12 Practical Obfervaiions thereon 
 
 L E C T. XII. 
 
 Of Distillation. 
 
 1 Fiftillaticn^ what 
 
 2 Fhe Arts concern'd therein 
 
 3 Biftillation of Wafio 
 
 4 Proof-Spirit 
 Fine- Stilling 
 Retlfication of Spirits 
 
 7 Proof of Spirits 
 
 8 Cordial Waters^ how made 
 
 9 Compound Dijlillation improved 
 j o Axioms and Canons 
 
 L E C T. XIII. 
 
 Of Oils and Salts. 
 
 1 Oils how exprefied 
 
 2 Effences how made 
 
 3 EJfsntial Oils 
 
 20I--203 
 
 203, 204 
 204—207 
 207--209 
 209 
 2 10 -212 
 212-214 
 214, 215 
 215-217 
 217 — 221 
 
 221—229 
 229 — 241 
 
 242 
 242, 243 
 244—246 
 246—248 
 248 
 249-251 
 251-255 ‘ 
 
 255 
 
 255, 256 
 257-260 
 
 262-266 
 266, 267 
 267 — 271 
 4 Effen - 
 
xxii 
 
 4 
 
 5 
 
 6 
 
 7 
 
 8 
 
 9 
 
 10 
 
 1 1 
 12 
 23 
 
 1 
 
 2 
 
 3 
 
 4 
 
 5 
 
 6 
 
 7 
 
 8 
 
 9 
 
 10 
 
 1 1 
 12 
 
 1 
 
 2 
 
 3 
 
 4 
 
 5 
 
 6 
 
 7 
 
 Table of CONTENTS. 
 
 EJfential Oils, how adulterated 
 
 271-274 
 
 Empyreumatic Oils rectified 
 
 274-276 
 
 Sugar refined 
 
 276-278 
 
 Elccofaccharums . 
 
 279, 280 
 
 ’Tartar refined 
 
 280-282 
 
 Nitre r^ned 
 
 283, 284 
 
 Pot-AJh, how made 
 
 285-287 
 
 — Its Kinds and Ufies 
 
 286-288 
 
 Soap, how made 
 
 288, 289 
 
 Axioms and Canons 
 
 289-293 
 
 L E C T. XIV. 
 
 
 Of Colours. 
 
 
 ’The Prifmatic Colours 
 
 294-296 
 
 Colours how changed 
 
 296-305 
 
 The Prifmatick Colours imitated 
 
 305 
 
 Laques prepared 
 
 306-30S 
 
 Carmine 
 
 307 
 
 The PrufTian Blue 
 
 308-310 
 
 Animal Colours 
 
 310-312 
 
 Metalline Colours 
 
 312 317 
 
 Callico Printing improveahle 
 
 313^314 
 
 The Indian Colours 
 
 315 
 
 Colours improved 
 
 3 H- 3*7 
 
 Axioms and Canons 
 
 3^7^319 
 
 L E C T. XV. 
 
 
 Of the common Pharmacy. 
 
 Hifiory of Pharmacy 
 
 321 - 3 M 
 
 Simple Waters 
 
 325 328 
 
 Tinihires and Infufions 
 
 328-332 
 
 Syrups 
 
 332-335 
 
 Eleliuarks 
 
 ■335-339 
 
 Oils, Unguents, Cerates and^Plaifiers 
 
 340-343 
 
 Axioms and Canons 
 
 343 > 345 
 LECT. 
 
Table of CONTENTS. 
 
 xxjii , 
 
 L E c T. XVI. 
 Of simple Pharmacy. 
 
 I <?/ Medicines 
 
 346-348 
 
 2 Emetics 
 
 349-352 
 
 3 Cathartics 
 
 35 '^-' 354 - 
 
 4 Sudorifics 
 
 355 -> 356 
 
 5 Alterants 
 
 357 , 358 
 
 6 Strengtheners 
 
 358, 361 
 
 7 Anodynes 
 
 361, 362 
 
 8 Regulation of Pharmacy 
 
 362-364 
 
 9 Axioms and Canons 
 
 364-366 
 
 L E C T. XVII. 
 Of Mineralogy. 
 
 1 Requifites to Mineralogy 3 ^ 7"‘375 
 
 2 Roafiing of Ores 
 
 3 S tamping and Wajhing 3 8 o- - 3 8 2 
 
 4 Fluxes 3S3— 3S6 
 
 5 Axioms and Canons 3 ^ 7 - ' 3 9 r 
 
 L E C T. XVIII. 
 
 Of Metallurgy.- 
 
 1 Metallurgical Operations 392 
 
 2 AJfaying 393 " 39 ^ 
 
 3 Smelting 394 
 
 4 Variation 39 7- -400 
 
 5 Gold and Silver Ores affayed and /melted 397-400 
 
 6 Ores of Copper ^ Tin^ Lead^ and Iron^ how af- 
 fayed and /melted 401—409 
 
 7 Brafs and Princess Metals how made 409, 410 
 
 8 Steely how made 412 
 
 9 Axioms and Canons ^ 41 2 --4 15 
 
 L E C T. 
 
xxiv Table of CONTENTS. 
 
 
 L E C T. XIX. 
 
 Of P Y ROTEC HNY. 
 
 1 Gunpowder^ how fyiade and tried 
 
 2 Pulvis Fulminans 421 --423 
 
 3 The firing Mixture of Iron and.Sulphur 423-425 
 
 4 Artificial Cor uf cations 425,426 
 
 5 A flaming Mixture of cold Liquors 42 7 --42 9 
 
 6 Solid and liquid Phofphor us 42 9 --4 3 4 
 
 7 Other Kinds of Phofphor us 4 3 4- - 4 3 7 
 
 8 Axioms and Canons 438,439 
 
 L E C T. XX. 
 
 Of Enlarging Chemistry. 
 
 1 Chemiftry^ howdivifihle and improveahle 440-449 
 
 2 Sal- Ammoniac^ how made to advantage 450-452 
 
 3 Amber diffolved 452-454 
 
 4 A hard Glafs^ how made 454- -456 
 
 5 Silvering Amalgam ' 456, 457 
 
 6 A curious Glue . 457-^459 
 
 7 Copper advanced nearer to Gold 459--- 46 1 
 
 8 Rules for improving Chemifiry and Arts 461 464 
 
 9 Axioms and Canons 464, 465 
 
 IQ Conclufion 466, 467 
 
LECTURE 
 
 I. 
 
 CONTAINING ^ 
 
 I. An Account of the Office and Objects oj 
 
 Chemiftiy. 
 
 II. "^fhe Chemical Treatment of Bodies. 
 
 III. Rules for making new Difcovcrics in 
 
 the Art. 
 
 I. 'HE Defign of thefc Lefturcs is 
 
 M enlarge the Bounds of Chemiftry,y%;z. 
 
 JL- by applying it to the Advancement 
 of Natural Philofophy, the Illuftra- 
 tion and Improvement of the known Arts, and 
 the Difcovery of new ones. 
 
 2. In profecuttng this Defign we would fpeak The Man- 
 to the Eye, rather than the Ear-, or indeed to the ner of 
 Underflanding, rather than the Senfes ; and by 
 
 'means of appofice Experiments, fcientifically ex- 
 plained, lead to the Difcovery of Phyfical Axioms^ 
 and Rules, of Pra 5 Uce for producing ufeful Ef- 
 feds, in the way of a Philofophical Chemiftry. 
 
 3. Philofophical Chemiftry we define, a rational Philo/o- 
 
 Arc of (i) dividing or refolving all the Bodies/»^^>^^ 
 within our Power (2) by means of all the Inllru- ' 
 
 ments we can procure 5 (3.) as well into integrant 
 
 as confticuent Parts j and (4.) joining thefe Parts 
 together again ; (5.) foas to difcover the Pfinciples, 
 Relations, and Changes of Bodies; (6.) make va- 
 rious Refolutions, Mixtures, and Compofitions ; 
 
 (7.) find out the phyfical Caufes of phyfical Ff- 
 fe6ls; and (8.) hence improve the State of natural 
 Knowledge, and the Arts thereon depending. 
 
 B 4. To 
 
7he Ob- 
 je^s of 
 
 2 . Lecture the First. 
 
 TheBu/t' 4. To explain this Definition, in a concife 
 general manner, is the Bafinel's of our firft Lee- 
 ^ ture \ and to illuflrate it fully, will be the Bu- 
 finefs of all the reft. 
 
 5. Our Definition confifts of eight Parts ^ the 
 firft whereof regards the Ohjefls of Cbemijlry, 
 
 (i.) Thefe Objefls are all the Bodies within our 
 Power. We fhould therefore, if it were pradti- 
 Chtmifry, take a particular View of the Contents of 
 
 the terraqueous Globe. To.abridge the Labour, 
 we fhall Tingle out the more capital and ufeful 
 Sorts *, and range them in fome Order, by way of 
 Specimen, or Sample, of that grand Repofitory 
 of infinite Materials 
 
 The Produdlions of the Earth are divided into, 
 I. Minerals. II. Vegetables^ and III. Animals. 
 I. Minerals are fubdivided into (i.) Metals 
 and their Ores, (2.) Salts, (3.) Sulphurs, (4 ) 
 Stones, (5.) Earths, and (6.) Semi-metals. 
 
 Cl ASS I. The Metals are. 
 
 Gold, ^ 
 
 CJafed. 
 
 II. 
 
 ^ickftlver. 
 Lead, 
 Silver, 
 Copper, 
 Iron, 
 
 Lin. 
 
 Salts. 
 
 Ranged according to their fpe- 
 cific Gravities, and compared 
 with their Ores refpedtively. 
 
 Alum, 
 
 Artificial Salt, 
 
 Bay Salt, 
 
 Borax, 
 
 Nitre, 
 
 Rock Salt, or Sal Gem, 
 Sal Ammoniac. 
 
 ^ In the Courfe, a Set of Specimens v/ns exhibited, in 
 conformity v/ith the following Lift, 
 
 III. SuL- 
 
Of Philofophical Chemifry. 
 
 III. Sulphurs. Amber ^ 
 
 Arfenic^ ubhite ^yellow ^ and redy 
 
 Auripigmentumy 
 
 Bitmneny 
 
 Brimjioney Commony 
 
 — Native y 
 
 Coaly 
 
 Jety 
 
 PetreoL 
 
 IV. Transparent Stones. 
 
 From the Dia- Ranged according to their 
 mond to C Hardnefs, which is their Cri- 
 
 CryJiaL 3 terion, as Gravity is of Metals. 
 
 'V, Opafce Stones. Alahajlery 
 
 AmianthuSy 
 
 Emeryy 
 
 Flinty 
 
 HamatiteSy 
 
 Loadjloney 
 
 Marble y and Porphyry y 
 Lapis Calaminaris y 
 Talcy 
 
 Tripoli y &:c. 
 
 VI. Earths. Boky 
 
 Chalky 
 Marly 
 Grey 
 Ocrey 
 Ruddle y 
 
 Terra Lemniay &:c. 
 
 VII. Semi-metals. 
 
 The Vitriolic are, 
 
 Vitriol y green and blue, viz, of Iron and Copper; 
 JVhite Vitrioly with other foreign kinds. 
 
 "Vlll. The Sulphureous Se M i-M E T A Ls are, 
 Antimonyy 
 ^ifmuthy ) 
 
 B 2 Cin- 
 
4 
 
 Lecture the First. 
 
 Cinnabar^ native^ 
 
 Mundick^ 
 
 Pyrites^ 
 
 Zinck^ &c. 
 
 II. Vegeta BLEs are divided into 
 
 Herbs ^ Berries^ Flowers^ Fruits^ Grains^ Seeds ^ 
 Roots y Barks y Woods y Juices^ and Excrejccnces, 
 
 Qlafs^, Herbs. Angelicay Baulmy Hyjfop^ Ro‘ 
 Jemary y Lavender y Sage, Fan- 
 fyy Fhymey JVormwoody &c. 
 
 II. Berries. Bay Berries y Coffee y Kermesy Ju- 
 
 niper y &c. 
 
 III. Flowers. JaJmiUy Saffrony Lillies ^ Mari- 
 
 ^ goldsy RofeSy Elder-Flowers y 
 Violets y Flowers of Broom y 
 Holly -Oaky &c. 
 
 IV. Fruits. Cocoa-NutSy Nutmegy Jamaica- 
 
 Peppery Long- Peppery Fama- 
 rindSy Caffia FfulariSy Pome- 
 granate y &c. 
 
 V. Gr A I N s. Ricey Indian Wheat y SagOy Millet y&cc. 
 
 VI. Se e ds. Beecb-mafty Cardamomy Gran. Paradif 
 
 Mufiard- Seedy Sun-jloser Seedy &c. 
 
 VII. Roots. Alkane ty Galangaly GentiaUy Liquo- 
 
 rice y Madder y Orris ^ Furmericky^c. 
 
 VIII. Barks. Caff ay Cinnamon y Clove-Barky Cor- 
 
 tex Peruv. MacCy Oak-Barky Winter's 
 Barky &c. 
 
 IX. Woods. Cedary Guaiacumy Logwoody Rho- 
 
 diumy SaunderSy &c. 
 
 X. Juices are fubdivided into natural, and ar- 
 
 tificial ; or into FcarSy and infpiffated 
 Juices. 
 
 Fears y or natural Juices, of the Sycamore, the 
 Birch, 
 
 In- 
 
Of Philofophkal Chemipry. 5 
 
 Jnfpijjated Juices z.xt ^widitd into (|.) Gums^ (a.) 
 
 Baljams^ (3.) Rofins^ and (4.) Sugars. 
 
 (i.) Gums. Aloes^ Gum Arabic., AJJa Fcetida., Am^ 
 moniacum^ Benjamin^ Bdellium^ 
 Galbanum^ Qamboge^ Majlich^ 
 Myrrhs Gum Elemi^ Opopanax^ 
 
 * Gum SandaraCy Gum Lac^ Cum 
 
 Tragacanth^ 
 
 Xr. (a.) Bal3AMS. Balfam Capiviy Qpobaljamumy 
 Balfam of PerUy TolUy ^c. 
 
 The turpentines y Wax^ &c. 
 
 XII. (3.) Rosins. CamphirCy Frankincenfey Rofm of 
 Guaiacumy Roftn of Jalaps Scam- 
 monyy Burgundy Pitchy Common 
 Rofiny Sang. DraconiSy kffc. 
 
 Xni. (4..) SuQARS. Honey y Mannuy Sugary &c. 
 
 XIV. Excrescences. Jews EarSy Agaricky 
 Mf^toBy the MoJfeSy Gallsy See. 
 
 III. Animals. 
 
 Clafs 1. Entire Animals., AntSy BeeSy Cantha- 
 ridesy Cochinealy MUlepedeSy ViperSy See. 
 
 II. Their solid Parts Boney Hart*s-horny 
 
 Ivory y Cuttle BonCy Elk's Hoofy 
 Human Skully Caftory See. 
 
 III. Concreted Animal Juices. 
 
 Goat's Blood and human Blood dryedy Lardy 
 Marrow y Sperma Cctiy Sec. 
 
 TV. Excrements. Albwn Gracumy Civet y Musky 
 
 Pigeon's Dungy Silky Sec. 
 
 6. Bodies have been ufLially confidered uudev Bodies 
 three general Clafle^, called by the Names of 
 Vegetable, Animal, and Mineral Kingdoms. 
 
 Divifion is, perhaps, too fcanty ; as excluding 
 tnany Particulars of the marine and atmofpherical 
 Regions. For in the Sea are found Coral, Shells, 
 Spunge, Bitumen, Ambergreafe, Mixtures of 
 
 B 3 Salt, 
 
6 
 
 7he gene- 
 ral Struc- 
 ture of th< 
 Barth, 
 
 Barth in 
 particular 
 
 Lecture the First. 
 
 Salr, Slime, Ficculencies, and the corrupted Parts 
 of Fifli, 13 c. which may pofilbly be irreducible 
 to any of the three Kingdoms. And the At- 
 mofphere abounds with Air, Light, Water, Me- 
 teors, Exhalations and Effluvia of the Earth, dif- 
 ferently combined ; fo as not to appear diftindlly 
 either of a Vegetable, Animal, or Mineral Na- 
 ture. 
 
 7. The OhjeBls of Chemijlry^ therefore, are 
 taken from the three larger Mafles, or Regi- 
 ons, of the Globe ; viz, the Earthy Water and 
 Atmofphere 
 
 8. Our Knowledge of the Earth reaches but 
 a little below its Surface. So far as Men have 
 
 ^dug, it appears a Compages of numerous folid 
 Siibffances, ranged in a diforderly manner ; 
 which may be phyfically necefflary, to afford 
 different Partitions, or Beds, of Soil, Gravel, 
 Clay, Stone, Coal, Marcafites, Ores, Gems, i 3 c, 
 each ferving as a Matrix to the other. 
 
 q. By Earth is commonly meant the Soil, 
 •Mould, or Coat, wherein Vegetables grow. This 
 Coat, which is but of little Depth, is the dire6t 
 and immediate Seat of Vegetation. And with 
 this Earth we chufe to begin our Experiments *, 
 propofing (i.) A general Analyfis of Garden 
 Mould; (2.) The ‘Preparation of a general kind 
 of Flux, for the affaying of Ores. (3.) The 
 general Method of affaying Ores for their Metal. 
 (4,) A general Analyfis of common Water. (5.) 
 A general Analyfis of the Air. (6.) A general 
 Example of the Method of reducing Bodies to 
 their integrant Parts. (7.) A general Example 
 of refolving Bodies into their conftituent Parts ; 
 and (8.) An Example of Reduffion, or the Me- 
 thod of recompofing, or recovering. Bodies after 
 Solution. 
 
 IJ. 
 
Of Philofophical Chcmifry. 
 
 7 
 
 II. 
 
 Ex PERIMENT I. 
 
 'The Analyfis of Garden Mouldy begun. 
 
 10. We took two Pounds of frefh, black 
 rich Garden Mould, and flirred it well in 
 Quarts of fair Water, gently warmed, then letting 
 the grofTer Part fettle to the Bottom, we liltred 
 the Liquor thro’ Cap-Paper ; and found that it 
 pafled confiderably muddy, or impregnated with 
 the finer Parts of the Earth *, which it would not 
 eafily depofite upon many Days (landing in a 
 quiet Place 
 
 11. The Defign of the Experiment is to ob- 
 tain a proper Liquor for difcovering the Mat- 
 ter which .the Earth affords to Plants in Vege- 
 tation, or the natural Juices, and natural Salts,- 
 of Garden Mould •, becaufe nothing feems capa- 
 ble of rifing in Vegetation, but what is foluble 
 in moderately warm Water, and will pafs the 
 Pores of Paper, fomewhat in the fame manner 
 as it does the natural abforbing Veffels, or Strai- 
 ners of a Plant. Whence the filtred Liquor of 
 our Experiment may be examined by chemical 
 Treatment ; as by Evaporation, or the way of 
 trying Mineral Waters^ &c. as we fhall fee here- 
 
 , after in our fourth Ledure. 
 
 12. Ores are the next ufeful Species of Earth 
 the general Treatment whereof, for obtaining 
 their Metal, depends upon the Ufe of the Bla^ 
 Flux. 
 
 * See this Experiment carried a greater length in teif. 
 IV. Exp. I. and II. 
 
 B 4 Ex- 
 
8 
 
 Lecture'the First.., 
 
 Ex PE R I ME NT II. 
 
 The Method of making the Black Fluic^ for the af- 
 d faying of Ores/^ 
 
 7he Black 1 3." We took onc Part Nitre, and two Parts 
 FUx. common Tartar*, and reducing each to Powder, 
 we mixed them together, and deflagrated the 
 whole in a Crucible, by lighting the Mixture 
 a-top ; which thus turns to a kind of Alkaline 
 Coal^ that is to be pulverized, and kept in a 
 clofe Glafs, to prevent its diflfolving, as it would 
 do in a moifl: Air. 
 
 14.. This Flux is of general Ufe ; "and to 
 have it ready at hand, fhortens the Bufinefs of 
 making Affays in Metallurgy ; and renders the 
 Operation more exadf, than when crude Tar- 
 tar and Nitre are employed ; becaufe the De- 
 flagration might thus carry off iome Part of the 
 Ore, and defraud the Account. For the fame 
 Reafon, the Mixture is here diredled to be fired 
 a-top*, otherwife a confiderable Part might be 
 Joft in the Deflagration ; which would prove 
 much more tumultuous and violent if the Matter 
 was thrown into a red-hot Crucible. 
 
 Experiment III. 
 
 ^he general Method of analyfing Ores, 
 
 Ores ana- 
 tyfed. 
 
 15. We took two Ounces of Copper Ore re- 
 duced to Powder, and mixed it, in a Mortar, 
 with twice its Weight of the black Flux ; 
 then, in a Wind Furnace, fufed it brifkly, that 
 it m.ight run thin, for about four Minutes : when, 
 fufFering the Crucible to cool, we broke it, beat 
 off the Slag, and weighed the Metal. 
 
 16. This Experiment ihews the Method of 
 treating any unknown Ore, to difcovcr, in the 
 
 way 
 
9 
 
 Of Philofophical Ch&mijiry. 
 
 way of Aflay, or Proof, the Kind and Proportion 
 Metal it contains. 
 
 17. The of the Effedl depends upon Rath- 
 Separation of the terreftrial, fulphurcous, or other 
 heterogeneous Parts of the Ore, ‘which are here 
 
 cither vitrified, or otherwife detained by the Flux-, 
 whofe Property it is to vitrify Earth in the Fire, 
 and ftrongly join with Sulphur; at the fame^ 
 time that it does no: alter the' Metal, but leaves 
 it to its own nature ; whence, by its fuperior Gra- 
 vity, it finks pure to the bottom of the Crucible -, 
 as being now made fluid, and fet free from the 
 heterogeneous Parts before mixed in among \ia), 
 
 c 
 
 18. TFater is generally divided into frit Water di- 
 frefli, with regard to the Ocean and Rivers*. 
 
 But it Teems divifible into as many different Spe- 
 cies, as the Earth is into Beds. Thus there arc 
 Mineral Waters of various kinds, according; to 
 the Mineral Subftances they run over, and become 
 impregnated with: tho* this Impregnation fome- 
 times happens in the way of Vapour, or Exha- 
 lation. Water, therefore, in the general, may be 
 as mixed a Body, as Earth in the general ; and 
 perhaps neither of them naturally exifts in any 
 confiderable Degree of Purity h). 
 
 Experiment IV. 
 
 A general Analyfts of common Water, 
 
 19. (i.) We found that common warm Water Water 
 throws up numerous Bubbles, and explodes, in analyfeL 
 the exhaufted Receiver of the Air-Pump ; and 
 therefore contains what may, by way of diftinc- 
 
 tion, be called .®ther or Spirit, 
 
 <2/ See the Left, on Metallurgy. 
 b) See Ua. V. 
 
 (2)lt 
 
ID 
 
 Th^ At- 
 
 fnnfphere 
 
 dinjided. 
 
 The Air 
 anahfed. 
 
 Lecture the First. 
 
 (2.) It contains a merely aqueous part, diftind 
 from ^ther, and from the Sediment'; as appears 
 in diftilling common Water, 
 
 (^3.) It contains a dry folid Matter, which is 
 either earthy or laline, as appears upon a full 
 Evaporation; and alfo from the Infides of Tea- 
 Kettles, which, after long Ufe, are lined with a 
 flony Matter, that beats off in Flakes or Cruds. 
 
 20. That Water is accounted beft and whole- 
 fomeff, which is lighteft, moft fpirituous, and 
 freed from earthy Sediment ; and thefe Properties 
 are ufually found in pure Rain Water: this being 
 naturally diftilled, or raifed by the Sun’s Heat, 
 from the Ocean and Rivers, into the Atmofphere, 
 and from thence returned again, much after the 
 manner of common Diftillation a), 
 
 21. The Atmofphere is a kind of dry Fluid, 
 no lefs effential to the Earth than the moift one. 
 It Teems as heterogeneous as the Earth or Water, 
 tho’ more rarified. It is diffimilar in its Parts, 
 like the Body of the Earth ; and has fomething 
 analogous to Beds, or particular Portions abound- 
 ing with different kinds of Effluvia, according to 
 the Differences of the Countries and Places over 
 which it extends. Thus over Mount Mtna^ or 
 other Vulcanos^ it muff neceiTarily be impregnated, 
 after the manner of certain Mineral Waters, with 
 the Fumes of burning Minerals ; over the Ifland 
 Ceylon^ with Aromatic Effluvia ; over London 
 with the Smoke of Sea- Coal h)^ 
 
 Experiment V. 
 
 A general Analyfn of the Air begun. 
 
 22. A proper Analyfis of the Air, or any inte- 
 grant part of the Atmofphere, has hitherto fcarcc 
 been attempted. 
 
 It) Sec LeSi. V. b) See Lcdi. III. 
 
 (l.) That 
 
Of Phitofophkal Chemtjlry. i i 
 
 (i.) That it is an elaftic Fluid appears by its 
 diftcnding Bladders, and breaking Glaffes, in the 
 cxhaufted Receiver of the Air-Pump. (2.) That 
 it is eflential to Life, appears by Animals dying 
 without it. (3.) That it may receive invifible In- 
 fluences or Alterations, as well as vifible Effluvia, 
 appears from its becoming poifonous by paffing 
 thro’ Fire ; and by its containing grofsSmoak, and 
 the fine Particles of fermenting or putrefying 
 Bodies : And (4.) that it is naturally a Com- 
 pound, appears by the Water it depofites in dry- 
 Salt of Tartar ; and by its changing the Colours 
 of various Bodies, iSc. 
 
 23. We fhall hereafter attempt a more particu-- 
 lar Analyfis of the Atmofphere^ in order to a Choice 
 of the beft Places for Flealth, Habitation, and 
 the Exercife of particular Arts; on account of 
 certain Properties in certain Places, arifing from 
 the different Mixtures, or Compofitions, of the 
 Air in different Parts a). 
 
 24. The Inftruments of Chemlflry are all thofe^^^ 
 we can any way procure b). There are feveral 
 Inftruments continually at work, for the im- 
 mediate Produdion of Effcdls, in the three 
 larger Maftes, or Kingdoms, bf the Globe, viz, 
 the Fdarth, Water, and Atmofphere. We evidently 
 find, that Metals and Minerals are formed within 
 the Earth; Vegetables on its- Surface, fhooting 
 into the /\ir ; Meteors in the Atmofphere ; and 
 Men, Beafts, and Birds in the Confines of the 
 two : The Phyfical Caufes of all which are to be 
 diligently fought out, as fo many Rules ofPrafUce, 
 
 25. The principal phyfical Agents in Nature 
 appear to be, (i.) Heat. (2.) Cold. (3.) Air, 
 
 the integrant Parts of the Atmofphere. (4.) Wa- . 
 ter. And (5.) proper Beds, or Matrices, This is 
 
 a) See LcB, III. P) See above §. 3. 
 
 Matier 
 
12 
 
 Lecture the First. 
 
 Matter of dired Obfervation ; and might occa- 
 fion the eftabliftiing of the four common Elements, 
 Fire, Air, Water and Earth. 
 
 The Sun. 26. (j.) T\iQ Sun is the principal Source of 
 Heat upon the Earth’s Surface, and the Con- 
 fines of the Earth and Atmofphere. Without this, 
 all the Bodies upon our Globe would doubtlefsgrow 
 rigid, lifelds, and fixed. ’Tis this that ftirs within 
 them, as the main Spring of their Adions. 
 -Hence Vegetation, and Animalization, are evi- 
 dently promoted ; and hence the Ocean and the 
 Atmofphere continue in a fluid State a ), 
 
 C$ld. 27. (2 ) Cold is correlative to Heat ; and tho’ 
 perhaps no more than a lefs Degree, or Abfence, 
 thereof, yet has, in the natural State of things, 
 an inftrumental Efficacy *, as in the condenfing of 
 Solids b )j the coagulating of Fluids c J, the fepa- 
 rating of Salts d)^ Spirits e)^ ^c. And by means 
 of Cold and Heat, ufed alternately, it fhould feem 
 that fome capital Operations of Nature are per- 
 formed, efpecially in the vegetable Kingdom, by 
 the Reciprocation of Day and Night, Summer 
 and Winter/). 
 
 28. (3.) Air, or any integrant Part of the At- 
 mofphere, is an elaftic Fluid, that expands with 
 Heat, and contrads with Cold ; fo as apparently 
 to generate Motion, and produce Effeds. It ani- 
 mates Fire, and has a great Influence upon the 
 Life of Animals : it alfo mixes in among, and 
 unites itfelf with. Bodies ; fo as to conftitute a ma- 
 terial Part thereof I*/ It is the great Receptacle of 
 
 0) See Le^^i. II. pajjim. 
 
 h) Which are rarified by Heat, but contrafled by Cold, 
 
 e) As aqueous Liquors into Ice. 
 
 d) As Salt i§ feparated in the Freezing of Salt-Water. 
 
 e) As Spirit is ieparated in the Freezing of Wine, uri- 
 jious Spirits, and diililled Vinegar. 
 
 f ) See Le^. III. 
 
 p) See Le^. Lil. 
 
 Effluvia 
 
Of Philofophical Chemifry. 1 3 
 
 Effluvia from the Earth, the Matrix of Meteors, 
 the continual Support of Birds, Beads, Plants, 
 and Men ; and is in fome degree nutrimental a). 
 
 is not only contained in the Earth, jfTater, 
 as in a Refervoir, but likewife floats in the At- 
 mofphere. In both Cafes it is actuated, ratified, 
 and put in motion by Heat *, fo as to prove indru- 
 mental in producing Effedls. Thus it produces 
 Clouds, Rains, Dews, Springs, and Rivers. It 
 refrelhcs the Earth, recruits Vegetables, and is the 
 Support of Fifli and other Animals, by convey- 
 ing Nutriment to all their Parts. It is alfo the 
 fird and immediate Inftrument of Fermentation, 
 Putrefaction, Corruption, and Change, in all ve- 
 getable and animal Subjeds^j. 
 
 30. (5.) Proper Beds, or Matrices^ alfo appear Matrias, 
 to have an indrumental Agency in the Production 
 of natural Bodies. Every SubjeCt of an Operation 
 is ncceflarily contained in fomething that ma^ 
 
 (i.) afford it a Lodgment, (2.) make fome Re- 
 fidance, and (3.) convey to it Heat, Cold, Water, 
 or Air, or determine their ACtions upon it. 
 
 Thus in Vegetation, the Matrix Earth fupports 
 the Seed, refids its Swelling, and conveys a 
 drained, or prepared, Moidure to it. The Ma^ 
 trices of Gems and Ores not only afford a proper 
 Lodgment to the SubjeCt-Matcer, but alfo refid 
 its Growth, by the Preffure of their Sides ; which, 
 however, give way a little, and at the fame time 
 drain and convey fuitable Juices to the SubjeCf. 
 
 And fomething of this kind is obferved of the 
 Fcctus in Utero^ the Hatching of Eggs, ^c, info- 
 much that Clofenefs, moderate Refidancc, or a 
 flow yielding of the Sides of the Matrix, and a 
 draining of the Juices through them (unlefs fup- 
 
 a) As it adds to the Subftance of Vegetables and Animals. 
 
 See Mr. V tgetable Staticks, and hereafter III. 
 
 b) See Uff. VII and XII. 
 
14 
 
 Lecture the First. 
 
 plied from within^ feem requifite for the Forma- 
 tion and Produdion of all Vegetable, Animal, 
 and Mineral Subftances. Whence we are furnifhed 
 with a capital Rule for the Improvement of Che- 
 miftry, natural Philofophy, and Arts; and taught 
 that, in order to imitate Nature, Chemiftry mud 
 not be confined to the foleUfeof Fire, as its In- 
 ftrument, but occafionally employ Water, Cold, 
 Air, Earth, and proper or Veflels. 
 
 Artificial 31. natural Inftruments^ there 
 
 Infiru- is a great Variety of artificial ones belonging to 
 Chemiftry, which feem to raife the Power of this 
 emijry, fome refpeds, above the Power of Na- 
 
 ture. Thus, by means of particular Menftriiums, 
 it performs Operations which Nature of herfelf 
 does not: for inftance, of all the Metals, only 
 Iron and Copper are found naturally converted 
 into Vitriol ; whereas Chemiftry makes Vitriols 
 even of Gold, Silver, Tin, and Lead. And hence 
 the Produdions of Art may be much more nu- 
 merous, than the Produdions of Nature ; indeed 
 they may be increafed at pleafure, to the great En- 
 richment of Arts, and the Enlargement of the 
 Kingdom of Man a ). 
 
 Vejfehy ^2. Another Set of Inftruments belonging to 
 ^tenfih' Chemiftry are V^fiels, Furnaces^ and Utenftls -, of 
 which there is a great Variety, for different Pur- 
 pofes, and capable of producing numerous Changes 
 in Bodies, by Amalgamation, Cementation, Fufion, 
 Fermentation, Putrefadion, Redudion, Cfc. 
 AnenjuSit, 33. We add to the above-mentioned a new 
 Set, viz. The Air-Pump^ the Condenfor^ Bigeftor^ 
 Microfcopes^Burning-Concaves^ Prifms^ Lenfes., Por- 
 table Furnaces and every other Inftrument that can 
 be invented, or procured, of advantage to the Art. 
 
 a) In this Light may the numerous Produftions of the 
 Chemical Trades be confider’d ; fuch as the Elfedts of Fer- 
 mentation, Diftillation, Dying, Soap making, the Art of 
 ■ Glafs, Metallurgy, iAc. 
 
 34. There 
 
Of Philofophical Chemijlry. 15 
 
 24. There are two capital Ways wherein Che- 
 miltry divides its Subjeds, by the feveral Inftru- 
 merits above-mentioned; viz. mto integrant Parts, 
 and into conftituent Parts. By integrant Parts we 
 underftand fimilar Parts, or Parts of the fame na- 
 ture with the Whole ; fo Filings of Iron have the 
 fame Nature and Properties as Bars of Iron. Un- 
 der this general Operation, fall thofe particular 
 ones of Triture, Filing, Solution, Amalga- 
 mation, Sublimation, And by confiituent 
 
 Parts^ we mean diflimilar Parts, or Parts of a 
 different Nature from the Whole ; as when arti- 
 ficial Cinnabar is divided into Quickfilver and Sul- 
 phur : and under this general Operation come all 
 kinds of Analyfes or Refolutions. ^ 
 
 Ex PERIMENT VI. 
 
 A general Example of reducing Bodies into their in- 
 tegrant Parts, 
 
 35. We took an Ounce of Quickfilver in 
 fmall Glafs, and poured upon it two Ounces 
 Aqua fortis ; then fet the Glafs in a Sand- Heat to 
 warm’: red Fumes fcon appeared ; and the Mer- 
 cury, or Quickfilver, difappeared. We added a Di<vifiott 
 
 ' little more Mercury, till a fmall Particle was left 
 undiflblved at the Bottom, that the Solution might 
 be faturated. Then we decanted the clear Liquor : 
 a Drop of which being viewed in a Microfeope no 
 Particles of the Mercury appeared feparate. 
 
 36. Here we find the opake and heavy Body 
 of Mercury tranfparently diffolved, and equally 
 diffufed in a Fluid, at lead ten times lighter than 
 itfelf; the Mercury ftill remaining unaltered 
 and recoverable in its priftine Form, barely by 
 Colledion or Aggregation, as we lhall prefently 
 fee a): fo that it is thus only divided into homo- 
 
 a) Under Experiment VIII. 
 
 geneous 
 
i6 Lecture the First. 
 
 geneous or integrant Particles, and not feparated 
 into Particles of different Kinds. ' ' 
 
 Experiment VII. 
 
 A general Example of refolving Bodies into their 
 confiituent Parts, 
 
 Brandyre. 37* We gently diftilled two Gallons of common 
 folved into Brandy by the Balneum Mariic,, which refolved it 
 its con- into Spirit of Wine and Water. For the Spirit 
 of Wine, being the lightcfl: Part, comes over firft, 
 and leaves a large Proportion, or about one half, 
 of Water or Phlegm in the Still. 
 
 gg. And thus Brandy is feparated into the two 
 very difierent, pr heterogeneous Parts, whereof it 
 confifts. And hence, by the way, all Rums and 
 Brandies contain one half Water, no way eflential 
 to them, that might commodioufly be left behind 
 upon their Tranfportation and Carriage. And 
 this holds ftill ftronger of Arracks, which ufually 
 contain three fourths Water, to one of Spirit a), 
 Aggn- 39 . Thcfe two general Operations of Che- 
 gatesand miftry bear relation to two general Strudurcs of 
 Mtxisy Bodies, the Aggregate and the Mixt, Ag- 
 
 ^ ^ * gregates in their Kefoiution conftantly retain their 
 Nature in every the fmallefl: Part, or Atom; 
 but when Mixts are refolved, the Mixture is de- 
 ftroyed, and two or more new Aggregates are 
 produced : thus when Brandy is refolved, Spirit of 
 Wine or Alcohol^ and Water are produced. 
 
 ^enfthle 4^‘ Every fenfible Mixt, or Aggregate, is 
 Bodies compofed of many infcnfible ones. Before Gold 
 compared can bccome fenfible to us, there muft be a Col' 
 
 ofinfen- q|T 
 
 numerous Parts that arc feparately 
 infenfible; yet all of them perfeft Gold, The 
 
 d) Sec ua, Vir. Exp. IV. and Ua, XII. Exp. IV. 
 
 • minuteft 
 
Of Philofophkal Chemifry. 1 7 
 
 Hiinutefl Grain of Cinnabar has in it two diffe- 
 rent Parts, Sulphur and Quickfilvcr. The mi- 
 nuteft Grain of Glafs contains Sand and fixed 
 Salt. And fo when Quickfilver is diffolved in 
 Aqua FortiSy the Jeaft affignable Portion of the 
 Menflruum contains a Quantity of Mercury 
 proportionable to the whole. 
 
 41. (4.) Either he integrant or the conftitu- Recompofi- 
 ent Parts of Bodies being once divided or re- 
 folved a)^ various Occafions in Chemiftry re- 
 quire them to be united again, for compofing 
 a Whole like the original Subjed:. This Ope- 
 ration is the Converfe of the former. Thus 
 by fimple Mixture we recompofe Brandy from 
 Alcohol and Water; and by Precipitation with 
 a Copper-Plate, colle6t the Qyickfilver difperfed 
 in Aqua Fortis. 
 
 Expe r I me n t Vin. 
 
 An Example of the Method of recovering Bodies af- 
 ter Solution. 
 
 42. Dilute part of the above Solution of njer re- 
 Quickfilver with twice its quantity of fair Wa- covered. 
 ter ; fufpend a Plate of Copper in the Liquor ; 
 the Quickfilver will foon fall in its natural 
 Form to the bottom of the containing Glafs, 
 and being then taken out, well wafhed and 
 dried, will be abfolutely indiflinguifhable from 
 other Quickfilver that has never been diffolved. 
 
 The Effe6l is owing to this, that Aqua Fortis 
 diffolves Copper more eafily than Quickfilver, 
 and fo lets the Qiiickfilver fall in proportion as it 
 diffolves the Copper. And this, by the way, is 
 a general Example of Precipitation. 
 
 a) Se? above, ^.3, 
 
 c 
 
 h) Exn. vi. 
 
 43 * 
 
i8 Lecture THE First. 
 
 V?e Prin- 43. (5.) To difcover the Principles and the Re- 
 Re- lations of.Bodies, and the Changes a) produced in 
 by the Operations of Philofophical Chemif- 
 Bodies, trya wc mufl ufe all our Senfes, aflihed by proper 
 bonx) diJcQ- Sets of Experiments, or particular Ways of Ex- 
 ^erable, amination *, otherwife we fliall learn but little of 
 the Powers of Nature and Art. In the Experi- 
 ment of Quickfilver diffolved in Aqua Fortis^ 
 we find by a flight Expedient, viz. by putting 
 a piece of Copper into the Solution, that the 
 Qiiickfilver, tho’ rendered invifible, is not de- 
 flroyed ; feeing it is thus recovered in its prif- 
 tine Form and Properties. 
 
 44. By cafual Experiment, Glauber difeo- 
 vered his Method of preparing mineral acid 
 Spirits by means of Oil of Vitriol : for hav- 
 ing once obtained this Oil, by an Analyfis of 
 Vitriol, he applied it to the Mineral Salts, and 
 found that it expelled their volatile Acids in 
 Fumes; and that thefe being more plentifully raif- 
 ed by Heat, and colledled again, made the acid 
 Spirits, fo ufeful in Metallurgy, Refining, Dy- 
 ing, Cfc. Thus one new chemical Production 
 may give Rife to many new Arts. 
 
 PheReb Refolutions and Compofitions 
 
 lu]]ottTand^‘^^^ by Chemillry h) are extremely nume' 
 Compofi- rous, and may be increafed ad infinitum. We 
 tiom of exhibited an Inflance of Refolution in the Ana- 
 Chemijlry. of Brandy : And to this Clafs of Refolu- 
 tions are referable all kinds of Depurations, Pu- 
 rificadons. Separations, Clarifications, 
 
 46. By Compofition we produce all the ar- 
 duaions“of^^^^^^^ Vitriols, Soaps, Glaffes, Cfr. and can 
 Compofi- compound thefe again in an almofl: infinite Va- 
 tion. riety. So that the Refolutions, Compofitions, 
 and Recompofitions in Chemiftry, feem to have 
 
 /z) See kbove, C- 3. h) Ibid. 
 
 no 
 
Of Philofophical Chemlftry. rg 
 
 t\o Bounds; whence great room is left for new 
 chemical Difcoverics. 
 
 ■47* (7) Whilft we^ carefully attend to the 7-^^ 
 feveral Steps of chemical Operations, we are led ficalCanfes 
 into fome fort of Knowledge of the Phyjual or of chemi- 
 Materidl Caufes of the ElfeCfs a) produced, as 
 may appear from our Attempts to affign the 
 chemical Caufes in the foregoing Experiments. 
 
 Hence the more Attention and Diligence we em- 
 ploy, the jufter Notions fnall we have of thefe 
 Caufes, or the nearer Approaches Ihail we make to 
 theDifcoveryofthem ;'and they being once certain- 
 ly found will afford us certain Rules of PrafUce^ to 
 be occafionally employed for producing the fame 
 Effe6ls again. For to difcover the Laufe of an 
 Effcd, is to difcover a Rule lor producing that 
 Effed. 
 
 48. (8.) The Improvement of natural Y^r\ow- "The Ad~ 
 ledge, of Chcmiftry itfelf, and of the Arts thereon 
 depending muff be the t onfequence of a due 
 Profecution and Improvement of Philofophical 
 Chemiftry ; which for Diftincfnefs fake, we fnall 
 hereafter confider, as it more imiTiediately re- 
 lates to (I.) Fire, (2.) Air, (3,) Earth, (4.) IVa- 
 ter, ("5.) Menjiruum^, (6. ) Fermentation and Pu- jeSis to be 
 tref action, (7.) Fhe Analyfis of Bodies, (8.) Fhe treated in 
 Synthejis of Bodies, (9.) Vegetable Cur ation, (^iQf tbefoUoiv^ 
 Vinous and acetous Fermentation, f 1 1 ) Diftillation, 
 
 (12.) the making of 0 / 7 j, (13.) Salts, (14.) Co- 
 lours, Byes, and Stains, Pharmacy 2ind Me- 
 dicine, (16.) Mineralogy, (17.) Metallurgy, (18.) 
 Pyrotechny, ^ and (19.J the farther Ufes of Che- 
 miftry : fo as to fhew v/hat has already been done 
 on thefe Subjeds, carry the View fomewdiat 
 further, and* recommend a fuller Profecution to 
 others* 
 
 d) See above, 3. h) Ibi b 
 
 C 2 49, 
 
20 Lecture the First. 
 
 Three rre- 49. It was faid in our Definition a)^ tha 
 Philofophical Chemiftry is a rational Art\ by 
 duBiTg which we mean that it may be conduced by 
 Rule, and need not be lelt to accidental Trial 
 cal Che- and cafual Experiment. The Rule for duly 
 conducting the Art we would endeavour to com- 
 prize under the following three. 
 
 III. 
 
 Rule I. 
 
 50. When a Body is offered^ in order to have 
 new Properties dif covered in it^ dijferent from thofe 
 general ones of Figure^ Gravity^ Elaflicity^ &c. 
 which come under Mathematical Confideration^ let 
 the Body be refolved^ by degrees^ into the fimpleft 
 conjlituent Parts^ which it^is capable of being fepa- 
 rated into by the Inftruments above defribed: And 
 let F rial be made with each particular part on a 
 variety of Bodies^ according to fome Analogy of a 
 previous Chemical Knowledge^ leading from one thing 
 to another^ in a fure or probable Method of Ratio- 
 cination. 
 
 Rule IL 
 
 51. Let the fveral Parts^ obtained by the pre- 
 ceding Analyfis^ be reunited^ beginning with two^ 
 and proceeding gradually to the whole Fb umber ; 
 ufing at firft the ge'ntleft^ then the intermediate., 
 and at lajl the highejt Degrees of Heat and Cold. 
 F'hus., for example., join the fixed Salt and Oil of a 
 Plant together^ firft by ftmple digefiion^ and after- 
 wards by boiling \ which affords a third Produdlion 
 dijfmilar to all the refi, and known by the Name of 
 Soap. So., again., melt the fame fixed Salt with the 
 Earth of the Plant \ and this will afford Glafs. 
 
 ^ j See above, §. 3. 
 
 Let 
 
Lei the laH Attempt he to reunite all the feparated 
 Parts of the Body j in order ^ if pojfible^ to form 
 the original Suhjiance again. 
 
 Rule III. 
 
 52. In every Operation performed let the great eft 
 Diligence and Exaltnefs of Obfervation he ufed., with 
 regard to all the principal Phcenomena and Ejfetis 
 produced *, let thefe Phcenomena he dtdy regifiePd^ 
 tabled., conjidered., and compared together., after the 
 Jirilleft Geometrical Manner \ the Refult whereof., if 
 there he no conjiderahle Errors committed., will lead 
 to a Knowledge of the fecret Springs, Motions, In- 
 Jiruments, and Means made ufe of by Nature for 
 producing Effects. And thus, with proper Care 
 and Application, juft Canons or Rides of Practice 
 may he formed. 
 
 53. The Art of Chemiilry having been but 
 little cultivated in this view, all we can at pre- 
 fent pretend to, is to make fome Offers at 
 forming fuch Canons or Axiom^s, andconhgn them 
 over to further Experience and Obfervation, to be 
 thereby verified, amended or rejected. But if a 
 competent number of juft Axioms 3 .ndiCanons were 
 once formed in this manner, others of a ftill higher 
 nature might be raifed from them ; till at length. 
 Practice and Experience would lead us to a true. 
 Theory ^ and that Theory back again to a more 
 extenfive and ufeful Pra6lice, 
 
22 
 
 Lecture the First. 
 
 Imperfect A xi o m s, or C a n on s, deduced 
 
 from the preceding Enquiry, for promoting 
 
 farther Difcoveries and Improvements in che- 
 mical and natural Knowledge. 
 
 54. (i.) TVe may learn fr-m our prefent En- 
 quiry^ that a true Chemifiry (as it may perhaps he 
 jujlly called,) is exercifed hy Nature in the Vegetable,^ 
 Animal^ Mineral^ Marine^ and Atmofpherical Re- 
 gions \ and that hy it all Bodies are produced, con- 
 verted^ renovated,, repaired,, and maintained : and 
 that in the cxahi Difcovery, hnitation, and Controul 
 of this nacii ai chemiftry, conftfts the Perfehiion of 
 the artificial a). 
 
 (2.) That neither the Eye, nor all the Senfes to- 
 gether, can give us any Information of the latent 
 Properties of Bodies, their Natures and Ufes, with- 
 out particular Pryals and Experiments, well attend- 
 ed to and confidered h ), 
 
 ( 3 . ) Ehat Exper ments are hut infignificant Fadls, 
 unlefs they have a direli life in Life, tend to the 
 raijing of Axioms and C anons, for improving our 
 Knowledge, and extending our Power over the Works 
 of Nature c). 
 
 (4.) That he who can chufe fit Suhjelfs, place 
 them in proper Matrices, or including Veffels, 
 and fupply them duly with Air and Water, Heat 
 and Cold, may probably produce great effedfs in Imi- 
 tation of Nature d), 
 
 (5.) That nature points out three Matrices for 
 producing Phyfical Effedis, different in Finenefs, 
 viz. Beds of Earth, Beds ofJVater, atid Beds of 
 Atmofphere : Beds of Earth for Minerals, of 
 Water for FifJj, and of Atmofphere for Birds, 
 
 a) See above, §, 7, 8, g, 21, 24, 25. 
 
 b) See above, §. 35, 36, 38, 39, 47. . 
 
 c) Pafjtm. 
 
 d) See §. 24, 25, 26, 27. 
 
 &C. 
 
Of Philofophical Chemifify. 23 
 
 ’ tcc ; ^he Confines of the Earth and Atmofphere for 
 Plants and Animals \ aisd a rarijied Mixture of all 
 Matters for Meteors, a) 
 
 ( 6 .) Tdhat Men may make ufe of the fame In- 
 fir uments as Nature does^ viz. Fire,^ Air^ JVater^ 
 and Earthy and confequently produce the fame kind 
 of Eff ells,, if Skilly that is^ Knowledge^ he not want- 
 ing, Whence to improve in Knozvledge^ is to improve 
 in Arts h ), 
 
 (7.) That Chemiftry is not confined to the Ufe of 
 Fire only\ hut,, in imitation of Nature,, may employ 
 Cold,, Air, JVater, and Earth upon Matter, in va- 
 rious Degrees of Smplicity, Combination, and- Mix- 
 ture-, which fhews an extenfive Method of enlarg- 
 ing the Bounds of the Art c J, 
 
 (8.) That Fire is not only an Analyfer in fome 
 Cafes, hut alfo a Mixer of Bodies in others -, and 
 this to the Advantage of Chemifiry : For if it only 
 feparated, it could produce hut few Efifells, in com- 
 parifon of that infinite Variety it now produces , both 
 by Mixture and Separation d ), 
 
 (9.) That it might he proper to try the Reci- 
 procation of Heat and Cold in Chemical Operations, 
 after the manner of Nature, in Day and Night, Sum- 
 mer and Winter e ), 
 
 (50.) That Body, in all its Forms, is the Oh- 
 jefl of Chemiftry-, not confidered mathematically, nor 
 mechanically, hut operatively and effeliively f), 
 
 ( 1 1 . ) That the Atoms, or primary fmall Corpuf- 
 cles of Bodies, are infenfible to us : Thus the firfi 
 Particles of Gold, Salts, 'Metals and Minerals 7n ay 
 float in the Air, and not he perceived hy us, 
 
 a) See § b) See § 25, 26, 27. r) Ibid. 
 
 d) See 28—45. § 25. f) See § 3. 5, 7, 
 
 49, ^ alibi pajjim. 
 
 c 4 till 
 
24 
 
 Lecture THE First. 
 
 till they aggregate or are colle51ed together^ and 
 make a fenfible Mafs^ or 'produce a fenfihle Effect a), 
 12 . "That fome Operation of the Mind is requifite 
 to digeft^ methodize^ and regifter Chemical Expe- 
 riments and Objervations \ without which we can- 
 not come to know the Laws obferved by Nature in 
 Phyfical Operations.^ nor be able to imitate them : 
 Lhe Chemiftry., or regular Proceffes., of the Mind 
 being here as necejfary^ as the corporeal Operations 
 themjelves h j. • 
 
 a) § 35, 36, 38, 39, 41. 
 
 b) See §. 3, 48, 49, 50, 51. 
 
 More Canons and Axioms might be drawn both from the 
 prefent LeSiure, and from all the following ; but the Oefign of 
 drawing any at all, is chiefly to recommend the Method, rather 
 than the Matters brought a lecond time under confideration. 
 
 LEC- 
 
25 
 
 lecture II. 
 
 CONTAINING 
 
 I. l!he Nature, Properties, Office, and life 
 in general. 
 
 IL Phe Nature of Celejlial, Subterraneous, 
 and Culinary Fire. 
 
 III. ' The Effie&s of Fire on the Atmofphere, 
 
 and Bodies of the terreflrial ' Globe. 
 
 IV. The Degrees of Heat regulated. 
 
 I. 
 
 I. U R prefent Defign is to fearch into the T'heprefent 
 
 f 1 Nature of Fire : This we fhall attempt 
 by means of Experiments, conduced 
 after the manner laid down in ourfirft Ledfure. 
 
 2 . All the phyfical Knowledge we can have Prelhni- 
 of a Subjed mud; arife from attending to its^«7^.^" 
 Properties and Effedfs. But thefc Properties-^^*^"^^*®' 
 and Effedls can never be difcovered without the 
 
 help of Experiments, which in phyfical Enqui- 
 ries are the only Interpreters between our Senfes 
 and our Reafon. Whence all thofe Notions of 
 Fire Ihould be rejedled as precarious and un- 
 found, that are taken from the diredl Teftimony 
 of the Senfes only, or from bare Reafoning un- 
 affifted by Experiments. In this Enquiry, there- 
 fore, the Mind is carefully to be kept unprepof- 
 feffed, and to wait for a full and proper Infor- ' 
 mation before it pronounce. 
 
 3 . By the general Name of Fire Men feem to rxrt.how 
 underftand a certain Senfation, or complex No- underjiood. 
 
 tion 
 
26 
 
 Lecture the Second. 
 
 ^he Eye no 
 judge of 
 Five, 
 
 *Ihe ^Quch 
 no true 
 
 judge 
 
 thereof. 
 
 don of Light, Pleat, Burning, Melting, 
 
 This Notion fhould be refolved or analyled, in 
 order to fee what Parts thereof are eifential, 
 and what precarious or arbitrary. 
 
 4. We Irequently find the Effeds of Fire pro- 
 duced where no vifible Fire appears. Thus 
 the Fingers are cafiiy burnt by an Iron heated 
 below the Degree of Ignition, or fo as to be no 
 way vifibly red-hot or fiery ; whence the Eye is 
 no Judge of Fire. 
 
 5. So likewife the Touch gives us no pofitive 
 notice of any Degree of Fire below the natural 
 Heat of the Body, or of any fo great as to de- 
 ftroy the Organ. 
 
 ^Cnofef- Again, the Effeds of Fire are often pro- 
 feniialto duccd without any manifell Signs of Burning, 
 Fire, Melting, i^c, as in Evaporations, Exficca- 
 tions, ^c. 
 
 7. If this Method of Exclufion and Rejedion 
 were purfued to its due length, we fhould per- 
 haps find no Criterion, infallible Mark, or Cha- 
 raderiftick of Fire in the general, but that of 
 a particular Motion, frruggling among the fmall 
 parts of Bodies, and rending to throw them off 
 at tile Surface. If this fhould prove the Cafe, 
 then fuch a Motion will be the Form or Efience 
 of Fire^ which being prefent makes Fire alfo 
 prefent, and when ablent makes Fire alfo abfent. 
 Whence to produce Fire, and to produce this 
 Motion in Bodies, will be the felf-fame thing a), 
 
 8. But the following Experiments will afford 
 us more Light, and fhew, (i.) Thar, in general, 
 both Solids and Fluids manifeft an expanfive Mo- 
 tion upon being heated ; (2.) That the dired in- 
 flammable Matter of Fuel is Oil, oranunduous 
 
 a) See Lord BeKon\ Philofophical Works, Englifh Ed. 
 
 Vol.II. , 3-433.^^ 
 
 Sub- 
 
Of Fire. 2 <f 
 
 Subftance; (3.) That no Fuel will burn or coa- 
 fume without the Adrniffion of frefh Air ; (4.) 
 
 That the Air, which has once paffed through 
 burning Fuel, is of itfelf unfit to animate Fire 
 again ; and, (5.) That Flame, exifts only, on the 
 Surface of Fuel. 
 
 Experiment I. 
 
 ^hat Iron expands with Heat, 
 
 9. We procured an Iron Ring to be made, 
 juft capable of admitting one end of a>folid Rod 
 of the fame Metal; then heating that End in the 
 Fire till it was red, and applying it to the Ring, 
 we found the Rod fo fwell’d, that it would not 
 now enter the Hollow which it fitted exadlly . 
 when cold. 
 
 10. This Experiment dire6Uy ftiews no more 
 than that Iron expands upon being heated ; but 
 as it has alfo been found to fucceed in many- 
 other Solids, it may be made general, till the 
 contradictory Inftances are produced in the way 
 of Exceptions a ). 
 
 ' Experiment II. 
 
 Hhat Fluids expand with Heat, 
 
 11. We filled the fpherical Cavity of a bellied 
 Glafs, having a long and {lender Neck, at three 
 different times, with (i.) Mercury, (2.) Water, 
 and, (3.) Spirit of Wine, to the fame height ; 
 then plunging the Glafs, fucceifively, into Wa- 
 ter (kept in the fame Degree of Heat, in all the 
 three Trials, as appeared' by a Thermometer) 
 we found that each Fluid fwelled very remark- 
 ably, or rofe up to a confiderable Height in 
 
 eij Cedar Wood has, upon fome Trials, been thought not* 
 to expand with Heat, or contrad with Cold. 
 
 the 
 
28 
 
 ‘Three 
 Kinds of 
 Fire, 
 
 Celejiial, 
 
 Zuhterrei* 
 
 neous. 
 
 Culinary, 
 
 T'he Sun''s 
 Heat, 
 
 Tlhe Purity 
 tf the Sh»s 
 H eat, 
 
 Lecture the Second. 
 
 the Neck of the Glafs, above what it flood at 
 betore the Glafs was placed in the hot Water. 
 
 12. This Experiment feems to hold of Fluids 
 univerfaily : fo that tor the prefent we may allow 
 the Motion of Expanfion, or Rarifadion in 
 Bodies, to be infeparable from Heat, or Fire in 
 the general. 
 
 II. 
 
 13. We proceed to confider xh\s general Fire 
 in its three Kinds, viz. Celejiial^ Subterraneous.^ 
 and Culinary. 
 
 15. By Celejiial Fire we principally mean that 
 of the Sun, without regard to the Fire of the 
 fixed Stars ; tho’ this perhaps may be of the fame 
 nature. 
 
 15. By Subterraneous Fire we undcrfiand that 
 which manifefts itfelf in fiery Eruptions of the 
 Earth, Vufcanos, or burning Mountains ; and 
 by any other Etfecls it produces in Mines, or 
 the more central Parts of the Earth. 
 
 16. By Culinary Fire we mean that vulgarly 
 employed in all Chemical Operations, and the 
 common Occafions of Life. 
 
 17. The Sun’s Heat appears to be the aduat- 
 ing Principle, or general Inflrument of all the 
 Operations of Nature in the Animal, Vegetable, 
 Atmofpherical, Marine, and Mineral King- 
 doms a). 
 
 18. Confidered in itfelf. Fire feems to exifb 
 in greatefl: Purity and Perfeflion in the Celeftial 
 Regions ; at leaft we are not fenfible of any 
 Smoke it yields : for the Rays of Light come to 
 us from the Sun, unmixed with any of that grofs, 
 terreftrial Matter found in Culinary and Subter- 
 raneous Fires. But allowing for this Difference 
 
 A ) See LiSi, I. i^. 
 
 the 
 
of Fire. 29 
 
 the Effe6ls of the Solar and Culinary Fire ap- 
 pear to be the fame. 
 
 19., The Effe6ls of Subterraneous Fires will alfo Suhter- 
 be found nearly the fame with thofe produced ramous 
 by Culinary Fire. Burnt Coals, Cinders, and ap- 
 melted Minerals are thrown up by Vsfuvius^ and 
 other Vulcanos. Warm m.ephitical Exhalations, 
 natural hot Springs, Steams, Vapours, Smoke, 
 
 Cfr. are found in feveral parts of the Globe, 
 riling much in the fame manner as if they were 
 produced by the Heat of a Furnace. Whence 
 it can fcarce be doubted that Subterraneous 
 Fires are of the fame nature with the Culinary. 
 
 20. And as all the three kinds agree in giving 
 the Motion of Rarifa6lion to Bodies, it feems 
 
 no way improper to reduce them to one; or to ha^e a ' 
 quit, for the prefent, the Celeftial and Subterra- near A. 
 neons, and keep to the Culinary Fire, which 'i^gneement, 
 more within our power, and every where ready 
 at hand to be employed in Experiments. 
 
 21. All Culinary Fire requires fome Pabulum Fuelnvhat, 
 or Fuel, wherein it either refides or is collected. 
 
 A leading Experiment therefore, in our prefent 
 Enquiry, is the Analyfis of Fuel; to difeover its 
 conlfituent Parts, and learn which of them is 
 more immediately adapted to receive or propa- 
 gate Fire. 
 
 Experiment III. 
 
 Fhat Oil is ejfential to Fuel. 
 
 22. We put a Pound of common Billet-Wood, AkadUr 
 reduced to fmall Pieces, into an earthen Retort, Expert-"^ 
 and diftilled v^ith a naked Fire into a large Glafs 
 Receiver. There came over(i.) an acid Water, 
 
 (2.) a redifh tart Liquor, (3.} Smoke, and a 
 
 grofs 
 
3 © 
 
 ‘That Coals 
 Qnxe their 
 Injiamma- 
 hility to 
 OIL 
 
 Lecture the Second 
 
 grofs, black, burnt Oil. The fire being made 
 and kept up ftrong at lafl, no more Liquor or 
 Oil afcen'dedi but (4.) a black Matter, exadtly 
 refembling Charcoal, remained behind: this 
 
 being taken out and burnt in the open Air, fell 
 into Aflies ; which by Diffolution in Water af- 
 forded (5.) a little fixed Salt, and (6.) an earthy 
 Subftance. 
 
 23. This Experiment appears to be general, 
 or to fucceed alike in all Wood, Coals, or folid 
 Fuel. We feparated the acid Water or red- 
 difli Liquor from the Oil by the Filtre ; and then 
 found that thefc aqueous Liquors would not burn 
 in the Fire ; no more would the Afhes, the Salt, 
 or the Earth, either fingly or in compofition : 
 fo that of all the Subftances thus obtained from 
 the Wood, the black Coal and the Oil are the 
 only inflammable ones. But the Coal remains 
 inflammable merely upon account of the grofs 
 Oil ftill lodged and clofely locked up therein, 
 and according to its peculiar nature, fcorched, 
 or turned black by the Heat employed in the 
 Operation. 
 
 " 24. If farther Evidence be wanted toprove’that 
 the Oil remaining in the Coal gives it its Black- 
 nefs and Inflammability; let it be confidered, 
 (i.) That all fcorched Oils turn black; and that 
 the more volatile Oil, which here comes over into 
 the Receiver, is black. (2.) That no other part 
 of the Wood, feparated by the Analyfls, is in- 
 flammable, befides the black Oil ; not the Coal 
 itfelf after it is become white or reduced to 
 Afhes by open Fire and Air, which is an Ope- 
 ration fufficient to diflodge the grofs black Oil, 
 that could not be raifed by a lefs F'orce. (3.) 
 That no other chemical Caufe can well be af- 
 figned for this Blacknefs and Inflammability. (4,) 
 That Wood, Pic-Coal, prove lefs imflam- 
 
 mable. 
 
of Fire. 31 
 
 mable the more they are deprived of their Oil. 
 
 (5.) And laftly, that the Calces of Metals, ren- 
 dered abfolutely uninflammable by Calcination, 
 appear to attrad this Oil out of burning Fuel, 
 fo as thence to recover their inflammable Prin- 
 ciple and true metalline Form a). 
 
 25. But without farther Proof we may ven- 
 ture, for the prefent, to conftitute Oil the foie 
 Principle, or inflammable Matter in f uel ; and 
 on this footing it will be proper to reduce our 
 Enquiry to the more oily Species of Bodies, and 
 make our Experiments chiefly upon thofe. 
 
 Experiment IV. 
 
 That Fire will not confume Fuel without the Ad- 
 mijjion of Air, 
 
 26. Having exadtiy fitted a hollow Cylinder 
 of Iron with a ftrong Skrew at each end, we in- 
 cluded a long Piece of Charcoal in the Cavity ; 
 then fkrewing both ends tight, we detained the 
 Cylinder in a ftrong Fire for feveral Hours; 
 letting it afterwards cool and taking out the 
 Charcoal we found it ftill black and no way ap- 
 parently confumed, altered, or diminifhed. 
 
 27. This Experiment, compared with the com- 
 mon Obfervation that Fuel burns and confumes 
 quickly in the open Air, fhews that Air is ne- 
 ceflfary to the Cor.fumption of Fuel; or that its 
 burning and confuming depend upon the Rari- 
 faefion, Diflodgment, brifle Agitation, and Dif- 
 charge of the Oil it contains ; which is the phy- ^ 
 fical Caufe of the Effecft. And hence we have the 
 
 a) Let proper Trial be made, whether the fixed Oil 
 cannot be feparated from powdered Charcoal by a ftrong 
 Lixivium of Pot-afti and C^icklime, fo as to form a Soap, or 
 otherwife exhibit this Oil to the Eye. See Lett. XVJIL 
 
 22. 
 
 reafon 
 
32 
 
 Lecture the Second. 
 
 reafon of the known Rule or Method of extIn- 
 guifhing Fire by fmotheriiig it, or keeping it 
 clofe from the Air. 
 
 28. But that the bare Motion of confined Air, 
 or its pafTing feveral times through lighted Fuel, 
 is not capable of confuming it, appears by the 
 following Experiment. 
 
 Experiment V. 
 
 ^hat Air which has pajfed thro" Fire , or ignited 
 Fuel^ is unfit to animate Fire again, 
 
 29. We caufed a wooden Box to be made, 
 perfedly clofe and tight, with Glafs Windows on 
 the fides. At the bottom of this Box was a Per- 
 foration exa6lly fitted with a hollow wooden 
 Plug, that joined to a tight leathern Pipe. This 
 Pipe at the other end communicated with the 
 Clack of a pair of Fland-Bellows, the Nofe 
 whereof entered at a Hole on one fide of the 
 Box *, fo that by this Contrivance it was eafy to 
 draw the Air out of the Box into the Cavity of the 
 Bellows, and return it into the Box again, without 
 admitting any other Air befides that originally 
 contained in the Box. We now fet a little Cha- 
 fing-Difh of live Coals in the middle of the Box, 
 and fccuring all the Joints tight from the exter- 
 nal 7 \ir, wc plied the Bellows ; which, indead 
 of increafing foon totally extinguillied the Fire ; 
 tho’ the Coals were by no means burnt to Allies, 
 but remained black and frefh when cold. 
 
 30. Hence it is manifeft, that even a bridt 
 Motion of fuch Air as has already paffed through 
 burning Fuel, is fo far from animating, that it 
 deadens or quenches Fire a)^ in the fame manner 
 
 a ) Let ,a proper Experiment be devIied, to fbevv what Al- 
 teration the Air fufrirs by painng through Lire. 
 
 as 
 
of Fire. 3 3 
 
 damped or fmothered ; the Oil of the Fuel not 
 being carried off for want of frefh Air. 
 
 ^r. This method of damping Fuel, or fuffer- 
 ing it firft to burn a little and then extinguifhingc^«rr^</. 
 it, teaches us a Method of rendering Fuel inor- 
 fenfivc and fit for the more curious Ufes, by 
 difcharging its grofs Smoke, fo as to leave a pure 
 charred Coal behind; 
 
 Thus for example, if Pit-Coal or Wood be 
 burnt, not in the open Air, but with a cover’d, 
 clofe, or mouldring Heat, till it ceafes to fume, 
 and be then immediately quite fmothered or 
 quenched by throwing on it Mould, Sand, or 
 Water, it becomes a charred Coal or Coak, 
 fit for the drying of Malt, or other curious Ope- 
 rations in which grofs Smoke would be pre- 
 judicial. 
 
 32. Another Method of obtaining a pure Fuel 
 is to chufe fuch an inflammable Matter as yields 
 little or no Smoke from thefirfl:; fuch, in par- 
 ticular, is Spirit of Wine ; or, in the next Degree, 
 
 Oil of Turpentine, or other thin ethereal Oih^ as 
 they are called j whereof Spirit of Wine is by the 
 Chemifls defervedly reckoned the finefl; or mod: 
 fubtile 
 
 Exp e r I m e n t VI. 
 
 ^hat Flame dwells and plays only about the Surface 
 of Fuel. 
 
 33. We filled a Lamp-Glafs with Spirit of 
 Wine, and another with Oil of Turpentine *, 
 then fetting fire to each it was vifible thro’ . 
 the GlafTes that both Liquors burnt or flamed on 
 the Surface only ; the Flame continually finking 
 lower and lower in the GlafTes as the Liquors 
 con fumed. 
 
 * See Lea. VI. and Xill. 
 
 D 
 
 34. 
 
34 - 
 
 Lecture THE Second. 
 
 34. This Experiment holds alfo of folid Fuel, 
 and appears to be univerfal. And hence again 
 we are diredled in the choice of our Fuel ; which, 
 to light quick, fhould be furnilhed with a thin 
 fubtile Oil on its Surface. Upon this principle 
 depend thofe fudden Methods of Illumination 
 pradtifed at great Entertainments or publick Re- 
 joicings ; and upon the fame Principle we might 
 eafily invent quick, commodious, and inofFenfivc 
 Ways of lighting common Fires, (ffc. 
 
 HI. 
 
 "TheEffeat 35. Flaving learned how to procure, prepare,. 
 of Fire, manage, and improve our Fuel a)^ we come 
 next to confider the Effe(S:s of Fire, produced by 
 means thereof, on the Atmofphere and Bodies of 
 the terreftrial Globe. 
 
 OntheAt- 3^* All Fire rarefies the Air that is near it, as 
 mofphere. appears from a Bladder including a fmall Portion 
 of Air, and lying in a warm Place ; for thus the 
 Airis made to fwell and diftend the Bladder: 
 Whence the Atmofphere muft needs be rarefied 
 by the Sun’s Heat, and produce Effecfts accord- 
 ingly. The Air alfo imbibes Smoke and carries it 
 aloft, at the fame time that the Fuel diminifhes 
 or wafles and falls into Allies. Whence the Air 
 becomes a kind of Menffruum, impregnated 
 with Smoke or the matter of Soot, in Places 
 where much Fuel is confumed h). 
 
 On par ^ 37. The Fffefls of Fire Upon particular Bodies 
 
 ticular Qj^iy learned from particular Experi* 
 
 Bodies, ; to make which, is the more immediate 
 
 Ofhce and ufe of Philofophical Chemiftry. Thus 
 in fome Bodies, as Ores, Fire procures Fufion 
 
 a) See above, § z;, 26,27, 28, 29, 31, 32, 33, 34. 
 h') See Lea. III. pajjim. See alfo Lea. I, §. 16. 
 
 and 
 
Of Fire, 35 
 
 and Separation; in others, as Sand and Pot afh, 
 
 Fufion and Mixture *, in fome Drynfefs and Ex- 
 liccation, as in Clay; in others Softnefs and 
 Pliability, as in Wax, according to the 
 Degree and Manner in which the Pdre is ap- 
 plied. But for the Condudl to be obferved in 
 this Application certain general Rules are re- 
 quired. And firft with regard to the kinds of 
 Heat: 
 
 38. There are in Chemiftry as many kinds kinds 
 Heat as. there are Mediums thro’ which it may 
 
 be conveyed, or Fuels that afford it. yemijry. 
 
 39. For common ufe. Heat is conveyed either 
 thro’ Water, Afhes, Sand, or directly thro* 
 the containing Veffel. 
 
 40. When Heat is conveyed thro* Water it is Balneum 
 called the Balneum- Marine or Water-Heat ; when M^riae, 
 thro’ Afhes, an Afh-Heat ; v/hen thro’ Sand, a 
 Sand-Heat ; and when thro* no intermediate * 
 Subfiance at all, a naked Fire. 
 
 41. Some Differences may be found in the Ef- 
 fe6ls produced by thefe different Heats applied 
 in the fame Degree: but they have not perhaps 
 been noted as they ' defer ve. 
 
 42. In feveral Bodies *tis evident that dry and 
 
 moift Heats have different Effects ; as we find 
 remarkably in the common culinary Operations 
 of boiling, roafling, baking, And hence, 
 
 where the Effe( 5 ts are required perfectly fimilar, 
 the fame kinds as well as degrees of Heat are 
 to be ufed. 
 
 43. The pureft Fire is that of Alcohol or per- The D/?- 
 fe6lly pure Spirit of Wine ; the next in Purity 
 
 that of diftiiled Oils ; the next, that of Charcoal, 
 or charred Turf ; and the impureft, that of Pit- 
 Coal : But all thefe have nearly the fame Effed, 
 v/hen received thro* the fame kind of Medium. 
 
 D 2 IV. 
 
3 ^ 
 
 Lecture the Second. 
 
 The De~ 
 ^t^ees of 
 lha!. 
 
 Uncertain. 
 
 Honv to he 
 regulated. 
 
 The jTrJi 
 Dezree. 
 
 O 
 
 Thefecend. 
 
 IV. 
 
 '44. The laft thing to be confidered is, how 
 to regulate and afcertain the Degrees of Heat in 
 Chemical Operations, fo as to produce the Ef- 
 fc 61 s required in every Cafe. 
 
 45. The common Direflions of the Chemifts 
 about this Matter are full of Uncertainty •, their 
 firft, fecond, third, and fourth Degrees of Heat, 
 meaning no precife Degrees meafured *by any 
 Standard. 
 
 46. To reduce this Affair to the necefTary Ac- 
 curacy proper Thermometers might be em- 
 ployed, filled either with Oil or Quickfilver, 
 and graduated from the freezing Point, or any 
 other fixed Point of Cold, up to the Degree of 
 boiling QLiickfilver. Thus would come in their 
 refpedtive Places, (i.) the Degrees of Heat belt 
 fuitcd to Vegetation, which might be ferviceable 
 in regulating the Temper of Green-Houfes. And 
 this temperate Heat is fit for extracting the 
 native Spirits of odoriferous Vegetables with Oil ; 
 as of Rofes, Jafmin, Cfr. and again, for making 
 the more curious Infolations, Cfr. 
 
 47. (2). The n £x t Degree of Pleat may be 
 accounted that of the human Body in a healthy 
 State, which is always greater than that of the 
 ambient Air. But when the Body is dead, it 
 receives the fame Degree of Heat with the am- 
 bient Fluid. This fecond Degree of Heat is 
 adapted to vinous and acetous Fermentation, 
 PutrefaClion, Exclufion of the Chick •, the finer* 
 Digeflions, the making of TinClures and Elixirs ; 
 and the Adepts have ufed it for the firfl: Digef- 
 tion of their Mercury, by carrying the including 
 VefiTel conEantly in their Pocket. 
 
 48. 
 
48. (3-) The 'third Degree of Heat in xhhfheihird, 
 Progreffion may be that of boiling Water, when 
 
 the Atmofpere is in a middle State of Rarefac* 
 tion. This Degree is required in the Diftilla- 
 tion offimple and compound Waters, the efTen- 
 tial Oils of Vegetables, and will coagulate or 
 confoiidate the Serum, Blood, and other animal 
 Juices, and confequently deftroy animals. 
 
 49. (4.) A fourth Degree of Heat may ht The fourth, 
 that wherein Quickfilver or Oil of Vitriol boils, 
 diftLls, or becomes volatile. This Degree is 
 
 fuited to the melting of Lead, Tin, Biimuth, 
 the fubliming of Sal Ammoniac and Sul- 
 phur ; the calcining of Antiniony, ^c. 
 
 50. (5.) A fifth Degree of Heat may be that 
 wherein Iron is kept in thin Fufion. By this 
 Degree all the other Metals are melted, viz. 
 
 Gold, Silver, and Copper ; Glafs is made, and 
 the unvitrifiable Stones calcined. 
 
 51. (6.) The fixth and highefb Degree of Heat sixth. 
 hitherto known, is that of the burning Lens, or 
 
 the Concave Mirror of M. Fillet te,, Tfcirnhaufen^ 
 and others. The Focus of thefe Glafles will even _ 
 volatilize what is called the Metalline or Mercu- 
 rial part of Gold, and vitrify the more ter- 
 reftrial. 
 
 52. And thus much for regulating the Dc- Ue De* 
 grees of Heat to be employed in Chemical Ope-^e^'^' -' 
 rations. We mufl next confider by what means 
 
 the preceding Degrees of Heat maybe excited 
 and preferved, as Occafions require. 
 
 53. (O. The Fuel mufl be chofen fuitable to 
 the Intention. The natural Sun in Summer fuf- 
 lices for Infolations. A Spirit-Lamp may be 
 made to give a moderate, or a confiderably ftrong 
 Heat, according to the number of Wicks em- 
 ployed and its Strength may be eafily mea- 
 fiired and adjufled by the Thermometer^ 
 
 D 3 
 
 54. 
 
38 Lecture the Second. 
 
 54. (2.) The lighter Fuels, fuch as Straw, 
 Leaves, Twigs, i^c. come next in order after 
 Spirit of Wine. (3.) Then Oils, Wax Rofin, 
 Pitch, And, (4.) Laftly, folid Wood, Coals 
 and Turf; all which may have their proper Fur- 
 naces, fo as to be burnt in the requifite Quan- 
 tity and with the requifite Fiercenefs or Slownefs. 
 great- 55- To excite the greateft Degree of Heat in 
 eji heat a Furnace the Rule is, to ufe the denfeft Fuel, in 
 •with Fuel the largefl Quantity, and with Bellows all round 
 the Furnace, incdiantly blown, and direded to 
 the central Point of the Fire wherein the Matter 
 to be acted upon is lodged. And in this manner 
 may be procured a Degree of Heat fufficient for 
 any ot the known Operations upon Metals, Mi- 
 nerals, Glafs, fpr. that require the ftrongeft Cu- 
 linary Fire a), 
 
 V. 
 
 Axioms and Canons, for the letter Knowledge 
 and Regulation of Fre. 
 
 We learn from the preceding Enquiry ; 
 
 1. That the dired Senfes ahbrd but little In- 
 formation as to the real Nature and elTential Pro- 
 perties, or Form of Fire h), 
 
 2. That the Form of Heat and Fire is a certain 
 bridled or reftrained Motion, excited, , main- 
 tained, and ftruggling in the minute Parts ot 
 Bodies, and tending to throw them off at the 
 Surface c), 
 
 N. B. If this Form he rightly difco'vered^ then to 
 introduce fuch a Motion among the Parts of any 
 
 a) moi e be defired upon this extenfive Subjefl, the Rea- 
 der may confult the Lo'd Bacon, Dr. Hook, Mr. Boyle, Mr, 
 E^celyn, Dr. Bohn, M. Homherg, Dr. Boerhaa<ve, and Dr, Stahl. 
 
 b) See above, §. 3, 4, 5, 6, 7. 3 5. 
 
 c) See §, 7, 8; 9, 10, 1 1, z6, 27, 28, 29, 32, 33, 34. 
 
 Body, 
 
Of Fire 3 9 
 
 Bt)dy will he to introduce Heat \ or^ if the Nature 
 of the Body he capable of it^ Ignition or Inflam- 
 mation. 
 
 3. That as the diredl inflammable Matter in 
 all Fuel is the Fat or Oil it contains a)^ the mofl: 
 oleaginous Fuel is the bell or richefl. 
 
 4. That Flame is the fmall Parts ofan inflam- 
 mable or confiderably unftuous Body, actually 
 fet on fire, or brifl<ly agitated and thrown off, 
 with a certain vibrative Motion, at the Surface of 
 that Body, into the open Air h). 
 
 5. That Flame cannot exifl without Oil a). 
 Whence it is that Afhes, Sand, Glafs, Stones, 
 and Earths do not flame upon Ignition, but ra- 
 ther damp and extinguifh Flame. 
 
 6. I'hat as Oil is the only inflammable Sub- 
 ftance in nature this may diredl us to the 
 means of preventing Conflagrations ; viz. by 
 ufing fuch Materials in Building as contain 
 little or no Oil. This Dire(fl:ion might be like- 
 wife extended to the making of incombuflibie 
 Paper for valuable Books and Manuferipts ; 
 new" Materials for Hangings, Furniture, ^c. 
 
 7. That as all Flame catches and exifls only 
 on the Surfaceof inflammable Bodies c)‘, we are 
 hence led to invent Methods of caling, or other- 
 wife defending, the Wood work of Ships and 
 Buildings from Accidents by Fire. 
 
 8. Tljat as the three capital kinds of Fire 
 have a near relation, and may be very well re- 
 duced to one, for human Ufes, viz. the culinary 
 kind d)\ Men may have reafonable Hopes of 
 performing confiderabie things by its means in 
 
 a) Sec above, §. Z2, 2j, 24, 25, 33, 34. 
 
 IJ See above, 26, 27, 29, 33. 34. 
 
 cj See above, §. 33. 34. 
 
 itj See above, §. 13- -20, 34, 3^, 
 
 D 4 
 
 imitation 
 
Lecture the Second. 
 
 imitation bf Nature ; as particularly in promote 
 ing and regulating Vegetation, the Ripening of 
 Ores, iffc, by artificial Heats. 
 
 9. That Fire and Flame are abolilhed or ex- 
 tinguilhed by Suffocation, or an Adlion contrary 
 to Ventilation a )y as being deftrudtive or preven- 
 tive of that internal Commotion and Difchargc 
 of the oily Particles of the Fuel by means of the 
 free Air, in which the nature of open and con- 
 fuming Fire and Flame confifts b). Hence 
 Fire and Flame are quenched by Water, or even 
 by Spirit of Wine or Oil of Turpentine, if a 
 live Coal or lighted Candle be fuddenly plunged 
 therein below the Surface of the Liquor. For 
 the Degree of Heat which Water, Spirit of 
 Wine, or Oil of Turpentine unfired, are capable 
 of receiving, being much lefs than that of a 
 burning Coal or Candle, the greater Heat is fub- 
 dued by the lefs 5 jull as Fire is quenched by 
 boiling Water. 
 
 10. That Heat is Fire in a lefs Degree, and 
 Fire only a greater Degree of Heat, on which 
 Lucidity, and, if the Matter be unCtuous, In- 
 flammability depend: as we fee in hammer- 
 ing a Piece of Iron till it becomes red-hot ; and 
 in the firing of Wind-mills, or Coach- wheels, 
 by their own violent Motion. 
 
 1 1 . That Heat mufi: aggregate and colleft in a 
 certain Proportion before it become cognizable 
 to the Senfes, or produce any manifeil Eifedls 
 ot Fire or Flame. Thus a Degree of Heat be- 
 low that of the natural human Body is infenfible, 
 or pafTes for a Degree of Coldnefs ; and the or- 
 dinary Motion of Wind mills. Carriages, & c. 
 
 aj See above, §. 26, 27, 29, 30, 31. SeeaTo Axiomz fore- 
 going. 
 
 h) See above, Ex^. II T, IV, V, and VI, 
 
 produces 
 
I 
 
 of Fire. 
 
 I produces no remarkable Heat; tho’ when the 
 i Motion is greatly increafed, or the Fridion ccn- 
 I fiderable, it foon excites Fire and Flame a,) 
 
 12. That all the Chemical Operations require 
 a certain or determinate Heat, in order tp their 
 being performed to the greateft Advantage ; and 
 1 that this Heat may be affigned and obtained, in 
 j every cafe, to the great Improvement of Che- 
 j miftry^J. 
 
 See above. §. 3, 4, 5, 6, 7. 
 h) See above, §. 44, 45. 
 
 LEG- 
 
[ 42 ] 
 
 LECTURE III. 
 
 CONTAINING 
 
 (i.) The general 'Properties^ [2.) Ingredient 
 (3.) Nature^ (4.) Office and Ufe of the 
 Atmofphere . 
 
 (5.) The Changes therein \ (6.) The Effedi s 
 it produces on the Terrefirial Globe^ and 
 (7.) In Chemical Operations. 
 
 I. 
 
 Suh- 
 
 jld. 
 
 The AtmO‘ 
 Jphere. 
 
 Its Ifnport 
 to Che- 
 mijiry. 
 
 To he ex- 
 a?nined in 
 three 
 States. 
 
 I. are now to enquire into the Chemi- 
 
 V V cal Nature, Properties, Ingredients, 
 Office and Ufe of the Atmofphere. 
 
 2. 'By xht Atmofphere wt underftand that whole 
 Mafs of rarefied Matter, or dry Fluid which 
 furrounds the Globe of the Earth to a confide- 
 rable Height. 
 
 3. To difcover the Nature, or the Influences 
 and Eflcdts of this Fluid, is of the utmoft Impor- 
 tance to Chemiftry; it being the general Fluid 
 wherein all Animals, Vegetables, and Minerals 
 grow, wherein our Fires burn, and every Che- 
 mical Veflel and Subjedt is included. 
 
 4. We ffiall examine it as exifting in three 
 States, viz. (i.) As it is an intire Mafs that 
 furrounds the whole Terraqueous Globe *, (2.) As 
 it confifts of diffimilar Parts, whilft it either lies 
 open and remains one with the refl, or elfe is 
 feparated therefrom by being included in our 
 Glaffesor VeflTels ; and (3.) As it is united with, or 
 fixed in Bodies. And from this Examination of the 
 
 Parts 
 
Of Air. 43 
 
 Parts of this general Fluid in different places we 
 may infer the nature of the whole. 
 
 Experiment I. 
 
 "That different Efluvia mix aitd form Clouds^ or unite 
 in the Atmofphere. 
 
 5. We unflopped a Bottle of ftrong Spirit fhat the 
 of Sea-Salt, and another of volatile Spirit of Sal 
 Ammoniac; and fetting the Bottles near each^'^/''^'*^' 
 other, the Vapours infenfibly arifing from them yatours, 
 met, and -formed themfelves into a very grofsvi- 
 
 fible Fume or actual Cloud, that continued for 
 fome time, but afterwards difappeared, or mixed 
 more intimately with the Air of the Room. 
 
 6. One of the’ Liquors here employed is an 
 acid Spirit, and the other an alkaline one, which 
 being mixed form a Species of neutral Salt or 
 Sal Ammoniac. And as their Fumes are no 
 other than fine Parrs of the Liquors themfelves, 
 that {till retain their Nature, they conftitute this 
 Kind of neutral Salt in the Air. 
 
 7. That fomething of the fame kind natu- 
 rally happens in the Atmofphere appears from 
 hence, that all Vegetables produce a kind of vo- 
 latile Salt by Putrefaction ; that the volatile Salts 
 of putrefying animal Subftances, no lefs than 
 the former, naturally go up into the Air, which 
 contains likewife fome Proportion of Sea-Salt 
 raifed from the Earth and Ocean : fo that if thefe 
 Particles meet they will neceffarily make a kind 
 of Ebullition, and unite into a neutral Subftance, 
 in the Atmofphere *, which may hence abound 
 with a variety of acid, alkaline, and neutral Salts, 
 the Signs whereof are evidently difeovered by 
 the Changes they produce in the Colours of dif- 
 ferent Bodies. 
 
 8. This 
 
44 
 
 ^ihe Fref- 
 fure of the 
 \4ir. 
 
 ’The Air's 
 ElajUcit}'. 
 
 Lecture the T n i r d. 
 
 i8. This Experiment therefore mayiliew to the 
 Eye fomevvhat of the phyfical manner wherein 
 Clouds and Meteors are generated in the Atmo- 
 fphere, and teach us that Saits naturally abound 
 therein: whence again we have the phyfical 
 
 Reafon of many Effects produced by the atmo- 
 fpherical Air, in the animal, vegetable, and mi- 
 neral Kingdoms, and in many Chemical Ope- 
 rations. 
 
 9. That the Atmofphere not only fupports 
 Vapours or Effluvia raifed into it from the Earth, 
 but alfo preffles upon terre (trial Bodies by its 
 Weight, appears from many Fneumatical Ex- 
 periments; of which kind we need only produce 
 two or three for the prefent. 
 
 Experiment H. 
 
 *-That the Atmofphere preffes upon Bodies by its 
 Weight, 
 
 10. This was made fenfible to the Hand ap- 
 plied clofe on the top of a hollow metallic Cy- 
 linder or Ring, about two Inches in Diameter, 
 fet upon the Air-Pump; for the Air being 
 drawn out of the Cavity underneath, the Hand 
 v/as remarkably prelTed inwards, and felt a con- 
 fiderable Weight. 
 
 1 1. The Effledt was likewife fhewn in a diffe- 
 rent manner to the Eye, by the breaking of a 
 piece of fiat Glafs applied clofe to the top of 
 the fame metallic Ring : for the Air being drawn 
 away from below, the Glafs was immediately 
 cruibed to pieces and fell inwards, with a loud 
 Noife and a confiderable Force. 
 
 12. Befides this Weight or Preffure the Air 
 or Atmofphere has likev/ife an elaftic Force 
 which is no Ids confiderable; as appears by many 
 Examples, and particularly by the following. 
 
 Ex- 
 
45 
 
 Of Air. 
 
 Experiment III. 
 
 ^hat Air is elaftic.^ or capable of forcing.^ difi endings 
 or fqueezing Bodies by its Spring. 
 
 13. We included a little Air in a Bladder, fo 
 as to leave it almoft flaccid, and tying the Neck 
 clofe put it into a Receiver, out ot which we 
 then exhaufted the Air (but not out of the Blad- 
 der 0 whereupon the Bladder immediately fwell- 
 ed and appeared as if full blown : but upon re- 
 admitting the external Air the Bladder was pre- 
 fendy fqueez’d up, or contracted to its former 
 Dimenfions. 
 
 14. The fecond and third Experiment there- 
 fore fliew that the Air or Atmofphere, both in its 
 natural unconfined btate, and when certain Por- 
 tions thereof are included in Veflfels, continually 
 exercifes a gravitating and an elaflric Power, ca- 
 pable of producing many EffeCts ; as continually 
 preiTing, by its Weight and Spring, all the Bo- 
 dies we know. It perpetually preffes upon the 
 Surface of the Earth, with a Weight equal to that 
 of a Column of Quickfllver whofe Bafis is that 
 Surface, and whofe Pleight is about 29 Inches ; 
 as manifeflly appears by the Barometer. 
 
 15. Plence the Atmofphere will infiniiate itfelf 
 into the open Pores on the Surfaces of all Bodies, 
 capable of receiving i’s component Particles. So 
 that the Pores of many Subfcances, though to our 
 Senfes they appear Vacuities, are full of common 
 Air ; which thus produces the proper EfteCls of 
 
 - Air, in Diftiiiations and many other chemical 
 Operations. 
 
 16. The Atmiorphere alfo, as a Fluid, mufl: 
 by the Lav/s of Hydrojlatics prefs Bodies equally 
 every way, and the internal Air of Bodies aCting 
 within, whiifl the external Air aCls without, nu- 
 merous 
 
46 Lecture the Third. 
 
 ^he EffeS}s 
 and com- 
 
 of 
 
 the Atm0‘ 
 fphere. 
 
 pounded 
 
 Nature 
 
 merous phyfical Effedls are hence produced in 
 that great Laboratory, the Earth ; where Bodies 
 are by natural Powers and Agents diflblved, pu- 
 trefied, changed, and carried off into that grand 
 Repofitory the Air. 
 
 1 7. And tho’ the Atmofphere itfelf be invifible, 
 yet we cannot but be fenfible of the EfFe6ls it pro- 
 duces, feeing they are by means of proper Contri- 
 vances and Obfervation, made perceptible even 
 by the Senfes, as in the preceding Experiments. 
 And thus, tho’ the Atmofphere be a rarefied and 
 moveable Fluid, fo that Bodies eafily pafs thro’ 
 it, yet broad Surfaces are greatly refifted by it. 
 And hence its Force, as a refifting Fluid, be- 
 comes maniiefl in high Winds, by driving and 
 difiipating the Clouds, and all kinds of Vapours 
 and Exhalations-, which are thus mixed in with 
 the Mafs of the Air, fo as to form a heterogeneous 
 Fluid, or Chaos of infinite Materials. 
 
 Experiment IV. 
 
 ^he ConftruEUon^ Nature^ and Ufe of the common 
 "Thermometer, 
 
 thermo- 18. (i.) The Common Thermometers areGlafs- 
 tneters ex- fill’d with tinged Spirit of Wine, and 
 plained, graduated, fo as to fhew, by the rifing or falling 
 of the Liquor, the Degrees of Heat to which it 
 is expofed. 
 
 19. (2.) Spirit of Wine is chofen for this Pur- 
 pofe, becaufe of ail known Fluids it is the mod 
 rarefiable with Heat, next to the Atmofphere it- 
 felf. Denfer Fluids might be employed, but the 
 Divifions would then be lefs ; and Water is unfit 
 for this Purpofe, as freezing with Cold. 
 
 20. C3.) Thefe Thermometers are the exadefl 
 Inftruments hitherto known for meafuring the De- 
 grees of Heat \ being filled either with Alcohol, 
 
 Brandy, 
 
Of Air. 47 
 
 Brandy, Oil, or Quickfilver, according to the fe- 
 veral Purpofes for which they are defigned a). 
 
 21. (4.) The common Thermometer fhews 
 the Warmth of the Air ; and that it always con- 
 tains fome Degree of Fire or Heat, more or lefs : 
 for Spirit of Wine has never been found to freeze 
 or congeal with any Weather, in any Climate ; 
 but rifes and falls in the Tube as the Weather is 
 more or lefs hot ; with regard to which alfo the 
 Atmofphere frequently varies. 
 
 Experiment V. 
 
 T * 0 determine the Proportion of Water contained in an 
 ajfigned Portion of the Atmofphere, 
 
 22. Having, by means of the Air-Pump and Jf^ater i» 
 an exa6l Pair of Scales, found the Weight of a 
 certain Quantity of Air contained in a large Glafs 
 VefTel, we included therein a known Weight of 
 
 well dried Potential Cautery (whofe Property is 
 powerfully to attraef the Moifture of the Air ;) 
 and kept this VefTel clofe flopped for feveral 
 Hours, during which time the Potential Cautery 
 was grown wet : in this flate we weighed it again 
 and found a confiderable Increafe •, which muft 
 be owing either to the Water attra« 5 led out of the 
 Air in the Glafs, or to a Condenfation of the Air 
 itfelf into an aqueous Fluid: for fuch a Fluid 
 might now by Diftillation be obtained from the 
 Matter thus run per deliquium V). 
 
 23. There is fome room to fufpedl that, if this 
 Experiment were made in Perfection, a Weight of 
 Water, almofl equal to that of the Air included 
 in the VelTel, might be thus obtained ; which 
 would prove a very extraordinary Difeovery, and 
 
 a) See LeB. II. §. 46. 
 
 b) The Experiment was not made with all the requifite 
 Exac^nefs. 
 
 fhew 
 
48 
 
 Frejh Air 
 required 
 in Rcffi- 
 ration* 
 
 Lecture the Third. 
 
 fliew what fome have endeavoured to prove, that 
 the Matter of common Air is little more than 
 Water a), 
 
 24. That much Water mull needs be contain- 
 ed in the Air appears evident from the Quantity 
 daily exhaled by the Sun, from the Ocean, the 
 Rivers, and the whole animal, vegetable, and 
 mineral Kingdoms. And as the Water fo raifed 
 into the Atmofphere muft neceffarily mix and join 
 with the faline and other Particles it there meets 
 with, and is capable ot diflblving ; hence the 
 Water of all our Springs, Rivers, and the Ocean 
 itfelf is impregnated with numberlefs Matters, that 
 little appear in Water. Andpoffibly to give the 
 animating or vivifying Spirit to Water, it is phy- 
 fically necelTary that it Ihould be perpetually re- 
 fined or refrefhed by this Kind of Diflillation, or 
 recruited and new impregnated with the Efhuvia 
 or fine Particles of all the Bodies floating in the 
 Atmofphere j after the fame Manner as a fkilful 
 Operator, to give his diftilled Waters the finer 
 Impregnation, fufpends a proper Mixture of In- 
 gredients in the Head of his Still. 
 
 Experiment VI. 
 
 nat a Refrejhment or Renewal of Air is necejfary 
 to Life, 
 
 25. If Animals or Plants be long continued 
 in the fame clofe, unchanged, or unrefreflied Air, 
 they will languifli and expire, much after the fame 
 manner as Fire v^^ould do, by a Kind of Suffo- 
 cation h), 
 
 26. Plence it appears that the Air, which has 
 once ferved for the Refpiration either of an Ani- 
 mal or Vegetable, is unfitted for the fame. Office' 
 
 a) See the L-ord Natural Hiflory of Winds, 
 
 h) See Letl. LI. §. 29. & alibi tajjim. 
 
 again. 
 
Of Air. 49 
 
 again, till it be recruited, as it feems to be, by * 
 mixing with the open atmofpherical Air. Every 
 Man is computed thus to derpoii a Gallon of 
 Air in a Minute ; whence, if the Number of 
 Animals and Vegetables on Earth be confider’d, 
 it fhould feem that the whole. Atmofphtre muft: 
 in time be defpoiled, uniefs Tome natural means 
 were ufed to prevent it. Indeed, on weighing the 
 matter attentively, one might fufpedf that the Par- 
 ticles of numberlefs Materials, fermenting * toge- 
 ther in the Atmofphere, produce a certain Spirit^ 
 or fine vivifying Subftance, that thus rer.ovates 
 and invigorates the whole Mafs, and renders it 
 again fit for Refpiration and the Suftentation of all 
 natural Bodies. And hence perhaps it is that no ill 
 Effedls are ufually felt from that immenfe Quan- 
 tity of grofs Smoak continually difeharged into 
 the Atmofpheres of large Cities. All Bodies 
 fuffer a kind of Tranfmutation, and may, by the 
 eftablifhed Courfe of Nature, go the fame rounds 
 again.' And hence alfo it is no wonder that Air, 
 when fo richly impregnated with Water, Soot, 
 
 Smoak, Salts, Oils, Kitchen-Exhalations, Cfr. 
 fhould prove in fome degree nutrimental. 
 
 Experiment VII. 
 
 ^hat loofe Air is contained in Fluids, 
 
 27. We put Water, Small-Beer, and Brandy ^/> /« //- 
 feverally into an Air-Pump Receiver, and 
 haufling the Air obferved numerous Bubbles to 
 arife and efcape from each Liquor, burfting upon 
 its Surface. 
 
 28. And in like manner is Air difeharged 
 from Liquors by boiling them over the Fire : 
 
 This is pradtifed upon Water, in order to make 
 See LeA. YU.paffim, 
 
 E 
 
 it 
 
50 
 
 Lecture the Third. 
 
 it alTord Ice without Blebs or Bubbles ; and a- 
 gain upon Oil defigned for "Thermometers^ &c. 
 But fuch Liquors as have b.en thus dil'charged 
 of their loofe Air, will be found to recover it 
 again by (landing open ; as if loofe Air were a 
 natural Ingredient in Liquor. 
 
 Experiment VIIL 
 l.hat the external Air may promote Solution. 
 
 29. We ftt fome Spirit of Sal Ammoniac and 
 ^ 7 tes 7 lu- Copper-Filings in vacuo^ and compared this with 
 tion. a like Parcel Handing for the fame time in the 
 open Air : that in vacuo had not coloured its 
 Menflruum, whilft that in the open Air afforded 
 a rich blue Tincture. Hence it appears that the 
 free Accefs of the external Air may promote Solu- 
 tion in fome Cafes ; where it feems to a6l by increa- 
 fing the Motion or Adion of the Menflruum. 
 
 Experiment IX. 
 
 That the external Air does not promote Solution in 
 all Cafes. 
 
 Tetin 30. Upon two Drams of whole Crab’s Eyes 
 fome Cafes poured in vaciio two Ounces of diftilled Vine- 
 gar, having firft boiled it to get out the Air. A 
 great Ebullition was immediately produced, the 
 Gage funk, and Air was generated. 
 
 31. Upon comparing this with the fame Expe- 
 riment made in the open Air, we found that the 
 Ebullition was much greater in vacuo than in 
 the open Air. 
 
 32. Hence we learn that Air may be generated 
 upon the mixture of certain Bodies, where it did 
 not appear before. 
 
 33. But 
 
Of Air. 5 1 
 
 35. But Experiments of this Kind muft be 
 made with Caution; the Quantity of Air thus ge- 
 nerated in fome Cafes being able to raife tiie Re- 
 ceiver, and throw it to a confiderable Diftance. 
 
 34. There is wanting an Account of all the 
 Mixtures that will produce Air in fo violent a 
 Degree ; among them may be reckon’d Oil of 
 Vitriol with Oil of Tartar per deliquium.^ 
 
 Fortis with Iron Filings.^ Spirit of Nitre with Oil 
 of Carawa)\ Cfc. 
 
 35. And thus Air may be generated betwixt 
 Solids and Fluids, and betwixt Fluids and Fluids, 
 by bare Mixture. The following P^xperiment will' 
 
 Ihew that Air may be extricated out of Solids, 
 and that it makes a conftituent Part thereof. 
 
 Experiment X. 
 
 Fhat Air enters the Compofition of Solid Bodies, 
 
 36. We put a Piece of hard Tallow into. an Iron ^irin So- 
 Retort with a long Neck ; then laying the krge'^^^^* 
 
 End of the Retort in a naked Fire, the fmall one 
 
 being plunged into Water, wediftilled in the ufual 
 Manner, and obferved that large Bubbles of Air 
 continually role and difcharged themlelves thro’ 
 the Water into the Air of the R.oom. At length 
 ceafing the Operation, and collebling all the vi- 
 able Matter either left behind or come over into the 
 V/ater, we found a very confiderable Lofs of 
 Weight, owing to the Air having been feparated 
 or forced by the (Irong Heat from the reft of the 
 i Tallow ^ 
 
 I 37. If it be obje6led that the Lofs of Weight 
 [might, in great Meafure, be owing to the Iron of 
 !iche Retort, which when hot has the Property 
 of drinking in Oil or Tallow ; it may be obfer- 
 
 ' * The Experiment was not made with requifite Care and 
 
 ; Caution. 
 
 E 2 ved. 
 
52 
 
 Lecture the Third. 
 
 ved (i) That the Effe 61 : is nearly the fame when an 
 Iron Retort is employed that has been ufed for 
 the fame Operation before *, (2) That the Ex- 
 periment anfwers proportionably when made in 
 Glafs i (3) That other Bodies befides Tallow, 
 particularly Hartfhorn, Bone, Tartar, yield 
 plenty of Air, when treated in the fame manner *, 
 (4) As there is fo large a Quantity of Air- 
 Bubbles difeharged in the Operation, and as Air 
 is proved to be a ponderous Body a the Lofs of 
 Weight may be fairly attributed to the efcape of 
 the Air. But (f ) a proper Gage may be contrived 
 to determine the exad Proportion of the Air 
 thus feparated, with refpefl to the original Matter 
 or Subjedl employed b), 
 
 3S. This Experiment is of great Importance 
 in Natural Philofophy and Chemiilry. When 
 fully verified and duly profecuted it may fhew 
 (i) that all natural Bodies confifi: of a very large 
 Proportion of Air, as one Part of their original 
 Compofition ; (2) That Air is neceflfarily required 
 to the Formation and Growth of Animals, Ve- 
 getables and Minerals; (3) That when Bodies are 
 diffolved or refolved a great Part of them turns 
 into Air again ; as when a Candle is burnt or 
 Fuel confijmed ; or as when Vegetables, Ani- 
 mals and Minerals ferment, putrety or corrupt ; 
 or as when Bodies are chemdcally analyfed or 
 treated by Heat. 
 
 39. (4) That the Matter which in the Diflilla- 
 tion of Hartfhorn, Tartar, and many other things 
 explodes and puffs thro’ the Luting, or fome- 
 times, when confin’d, burlls the Glafifes or Vef- 
 fels, is the Air fet free by the Fleat. 
 
 a) See above, Exp. II. 
 
 b) See Mr. Hale'$ Vegetable Static:, under ehe Analyfis 
 of the Air. 
 
 40. 
 
Of Air. 
 
 40. (5) That the Air thus naturally conden- 
 fed, confined, and intermix’d as a conftituent Part 
 in Bodies, has a great Share in their Diflblution *, 
 for being violently ratified it breaks the parts in 
 pieces and flies off, 
 
 41. ( 6 ) But leaving the Experiment to be 
 further verified, and made general, if capable 
 thereof, we fhal! anticipate no more, but pro- 
 ceed to reap the Fruits of the prefent Enquiry, 
 
 II 
 
 Axioms and Canons derived from the Enquiry, 
 
 1. We learn from,the preceding Enquiry that 
 the Atmofphere, confidered as a Whole, and a- 
 gain as confiding of an infinite Number of Ingre- 
 dients, is the Phyfical Caufe of numerous Effed:s5 
 not only in the Air itfelf, but likewife upon the 
 Surface of the Earth, in the fubterraneous Regions, 
 'in the Exercife of numerous Arts, and particularly 
 in Chemical Operations a'). 
 
 2. That it is the phyfical Office and Ufe of 
 the Atmofphere to affift in raifing the Vapours 
 and Exhalations of the Earth h\ and to ferve as a 
 general Matrix for them c), wherein they are 
 all blended together and fermented, or fome way 
 changed in their Nature, fo as to perform new 
 Offices, or recruit the vegetable, animal, and 
 mineral Kingdoms, when fuch enriched Vapours 
 fail back again in Rain or Dew to the Earth d), 
 
 3. That it is the Nature of Air to infinuate 
 itfelf into Fluids unite and fix in Solids, fo as 
 
 'a) See above, Exp.ll. III. IV. V. VI. VII. VIII. IX. X, 
 
 b) See Ex{>. I. 
 
 c) See Leil. I §. 16. 
 
 al) See §.25, 26. ief alihi pajjlm, 
 
 i) §. zj, 28. 
 
54 
 
 Lecture the Third. 
 
 naturally to make a conftituent Part of 
 both a), 
 
 4. Hence may be conceived, in general, how all 
 the Changes happen in this great Chaos the At- 
 mofphere ; viz. according as floating Particles of 
 different Kinds chance to meet, fo as to form 
 confiderable Aggregates or Colledions ; and ac- 
 cording as thele are favoured by the requifite De- 
 grees of Heat, Cold, Drynefs or Moifture. So, for 
 example, a Cloud of nitrous Spirit meeting with 
 a Cloud of oily Particles might fuddenly pro- 
 duce Corrufeations, as in the mixing of Spirit of 
 Nitre and an eflTential Oil i?). And in this man- 
 ner may the Generation and Phenomena of all 
 the Meteors be chemically explained. And thus 
 the Occurfions of various Parts of different Bodies 
 in the Atmofphere may be the Caufe of the Me- 
 teors, fiery Winds, Explofions, Thunder, Light- 
 ning, the Aurora Borealis, and other Phsenome- 
 na, which vve can imitate by certain Mixtures, 
 in the way of Philofophical Chemiflry c). 
 
 5. That the Atmofphere is an univerfal In- 
 ftrument, in the Hands both of Nature and of Art, 
 for producing Effedfs, whether on the Surface of 
 the Globe, in the Bowels of the Earth, in the 
 Air itfelf, in the Laboratory, or in other human 
 Works d). Thus it caufes Fire to burn, and 
 Bellows are but Engines to convey it thereto. 
 
 6. That as Air defeends, and adts m.ore forcibly 
 in the iubterraneous Regions, on Account both of 
 its greater Denfity there, and of the fubterraneous 
 
 §. 27, 28, 56, 37, 38. 
 
 h) See Exp. I. 
 
 c) See Mr. Lemerys Philofophical and Chemical Explana- 
 ticn of Subterraneous Fires, F.arthcuakes, Hurricanes, I’hun- 
 derand Lightning, in the Frc 7 ich Memoirs, Anno 1700, 
 
 See the whole Le^ure See alfo LeSl, I. 
 
 • Heat ; 
 
Of Air. ' - 55 
 
 Heat; hence Vulcanos and more violent Fires 
 may happen there than upon the Earth’s Surface 
 a). And poffibly this greater Heat and Power 
 of the Air below is necefTary to the Produdion of 
 Minerals and Metals h), 
 
 7. Hence we may learn the phyfical Caufe 
 why in the open Air diftilled aromatick Oils lofe 
 their native Spirit, grow thick, and terebinthinate; 
 why Wines grow flat or lofe their Brifknefs ; why 
 pale volatile urinous Spirits grow red; why Mi- 
 neral Waters lofe their Virtue; and how Air has 
 in all refpedls a powerful Influence upon Liquors ; 
 as being a dry Fluid in brifle Motion, whereby it 
 eafily lays hold of and carries off all the moft 
 fubtile and volatile Parts of Fluids, leaving the 
 grofler behind, and thus changes the Texture, 
 Colour, and Confiflence thereof c). 
 
 8. That the Atmofphere is, perhaps, the mofl 
 compounded and diflimilar Mals in Nature ; 
 confifting of an elaftic Part, and the Vapours 
 and Exhalations arifing from all the folid and 
 fluid Bodies of the Globe, Salts, Oils, Minerals, 
 Metals, Cfc. d), 
 
 ' 9. That the Air is the Caufe of numerous Ef- 
 fe6i:s, ill aferibed to other Cauf^s by the ancient 
 Chemifls, who for want of the Air-Pump and 
 other Contrivances, were ignorant of the genuine 
 Properties and Effe6ts of the Air e). 
 
 10. That the component Parts of the Atmo- 
 fphere are coarfer than thofe of Fire. For the 
 
 a) See LeSi. II. 
 
 b) See above, Exp. X. See alfo the tenure on Metillurgy 
 hereafter. 
 
 c) ^t&Exp. I. VI. IX. k §. 18. 
 
 d) See Exp, I. tSc. 
 
 e) See£^v^. Ylll.IX. X. 
 
 E4 
 
 com- 
 
56 Lecture the Third. 
 
 component Parts of the Atmofphere will not pafs 
 thro’ Glafs a). Stones, Metals, &c, as Fire does. 
 Alio Water, Lixiviums, Oils, pafs where Air 
 cannot •, as we fee in Bladders, Wet-Leather of 
 the Air-Pump, &c. Hence the Air may be arti- 
 ficially excluded from many Bodies. I?). 
 
 11. That the Atmofphere is continually at work 
 upon all the Bodies Subjedl to its Power, in the 
 way of a Menftruum; whence Iron Handing in 
 the open Air is corroded •, imperfedl Glafs dif- 
 Iblved ; Salts and Sugars run into Liquor •, and 
 the Bodies of Animals, Vegetables and Minerals 
 prey’d upon r). 
 
 12. That there is a continual Reciprocation 
 betwixt the Earth and the Atmofphere *, they 
 mutually diftilling, as it were, or throwing off 
 Matters from one into the other. Thus the Earth, 
 by the Sun’s Hear, fublimes fome Parts of all 
 things into the Atmofphere, and the Atmofphere 
 again precipitates them to the Earth d). 
 
 , 13. That the different Succefs of Chemical 
 
 Operations may be greatly owing to the parti- 
 cular Vapours or Effluvia floating in the Labo- 
 ratory where fuch Operations are performed f). 
 Thus if Salt of Tartar be run per deliquium^ 
 wlaere Vinegar is diftiliing, it becomes regenera- 
 ted Tartar ; a thing very different from the in- 
 tended Oil. 
 
 14. As Air always adheres to the Surfaces of 
 Bodies, and as the Surfaces of Bodies are enlarged 
 by pulverizing them /) i when we would exclude 
 
 cT^, See Exp. II, III. V!I. VIII. IX. 
 
 1) See Exp. II. III. VII. VIII. IX. 
 
 c) See Exp. I. II. V. VI. VII. VJJI. IX. Se^ alio below, 
 Jx. 20 . 
 
 d) See Exp. J. Sc Le^. I. fojjlm. 
 f) See Exp. I. 
 
 /) bxExp.lL 
 
 Air 
 
Of Air. 57 
 
 Air in Chemical Operations, the Subjed Ihould 
 not be pulverized. 
 
 15. That the open Air has a powerful Effica- 
 cy in many Chemical Operations, efpecially in 
 Mixture a\ where it often adls mechanically by 
 its Weight and Motion ; as in the mixing of 
 Oil of Turpentine with Salt of Tartar, which 
 does not fucceed in mcuo^ or in high mountainous 
 Places. 
 
 16. That the Accefs of Air is not neceflary to 
 certain Fermentations, or Ebullitions, and Solu- 
 tions •, fome of them proving more violent in 
 vacuo^ than in the open Air h ), 
 
 17. That no Degree of Cold, or Condenfa- 
 tion, has hitherto been able to deprive Air of its 
 Fluidity, or render it confiftent c). If there were 
 fuch a Power exerted in Nature, it would deftroy 
 all Animals and Vegetables, and perhaps flop 
 the Growth of Minerals a), 
 
 18. By comparing the prefent Enquiry with 
 the preceding, it appears that Fire cannot fepa- 
 rate Oil from Bodies, without the Admiffion of 
 the free Air. Whence in the roaffing of fulphure- 
 ous Ores, or obtaining of white Afhes from 
 Bones or Vegetables, we are direded to ufe an 
 open Air, as well as a naked Fire. 
 
 19. That the Air is in a Kind of perpetual 
 Motion e). Whence it performs all thofe natu- 
 ral Offices, that cannot be performed in a Va- 
 cmm. Thus leaven’d Paffe will not ferment or 
 rife, nor Wine work, nor Fleffi putrefy, nor 
 Fru:t corrupt, after the ufual manner, when placed 
 in vacuo, 
 
 a) See Exp VIII. 
 
 b) See Exp, IX. 
 
 A See IV. 
 
 d) See Exp. VI. & X. 
 
 e] See Exp. I.&IV. SzsslIHqAx. 12. & 17. 
 
 20. That 
 
58' Lecture the Third. 
 
 20. That as all kinds of Particles naturally 
 float in the Air a), the Air may on this Account 
 aft as an univerfal Menftruum, and in time dif- 
 folve any Body expofed to its Adlion ; becaufe, in 
 tradtofTime, the Particles capable of difiblving 
 it mufl: neceflfarily come at it I?). 
 
 21. That many Arts may be a(Tifl:ed, or car- 
 ried on to better Advantage in fome places than 
 in others, by the means of certain Particles 
 floating in the Air of one Place more than ano- 
 ther. Thus ’tis faid that the Scarlet Dye is better 
 (truck at Leyden^ than in other Places of Hol- 
 land^ where the Water and Atmofphere are not 
 fo impregnated with the Effluvia, Exhalations, or 
 line Particles of the Dye c). 
 
 23. Hence alfo we are directed to chufe pro- 
 per Seats for Health, and Habitation, as well 
 as for Operations and the Exercife of Arts d). 
 
 See Exp. I. Sc alihi pajjtm, 
 
 b) See Jx. II. 
 
 f) ScQ Exp. I. & alibi pajjim. 
 
 d) There are various Methods of trying the Wholefomenefs 
 or Un wholefomenefs of Airs and Places ; as by finding their 
 Degree of Moifture feveral ways ; by the Changes of Colour 
 produced in white Linen, or ftained Paper, left out in the Air ; 
 by expofing Copper-Plates to (hew the Colour of the Vitriol 
 thereby made ; and many other Expedients might be contrivM 
 tor that Purpofe. [ See Mr. Natural Hiftory of the 
 
 Air.] 
 
 LEC- 
 
[ 59 ] 
 
 LECTURE IV. 
 
 CONTAINING 
 
 The Solid or Earthy Matters of the Terrefrial 
 Globe clajfedy and examined^ under (i.) 
 Garden Earths (2.) Bolar Earths (3.) 
 
 Saline Earths ; (4.) Sulphureous Earths ; 
 
 . (5.) Stony Earths ; and^ (6.) Metallic 
 Earths. 
 
 I. TXT E now come to enquire into the Sub- 
 
 y Y earthy Contents of the Globe \jeei. 
 more particularly into the Parts concerned in 
 Vegetation. 
 
 2. We fhall begin with the Earth’s Surface, 
 and defeend down gradually, fo far as Men have 
 hitherto dug. 
 
 3. The Earth’s Surface is generally found Upper 
 
 vered with Verdure, or a Vegetable Coat, znd Coat of 
 in fome Places with Sand, Duft, or Mud. the Earth, 
 
 4. Under this fuperficial Coat there ufually 
 lies a Bed of Mould, or Underturf-Earth, of 
 different Depths, from one Foot to two, three, or 
 more, in different Places. (1.) This Mould, or 
 Underturf-Earth, is the proper Matrix of Vege- 
 tables, and will come to be firfl: examined in 
 Order. 
 
 5. We fhall next proceed to the other Spe.c\ts The Species 
 of Earths that lie beiow, viz. (2.) the Bolar -^of Earths. 
 (3.) the Saline ; (40 Sulphureous; (5.) the 
 
 Stony ; and (6) the Metallic. For under thefe 
 
 fix , 
 
6o 
 
 Mould a- 
 naiy fed by 
 Water. 
 
 Lecture t h e. F o u r t h. 
 
 fix general Clafles, we apprehend, may all the 
 earthy or folid Matters of the Globe be ranged. 
 
 6. It will therefore be our Endeavour to give 
 a general Example of the Method of treating 
 every Species, fo as to difcover their Natures, 
 Offices, and Ufes. 
 
 Experiment I. 
 
 7 he farther AnaJyfis of Gar den- Mould or Underturf - 
 Earth hy Water a). 
 
 7. (i.) We took four Pounds of freffi, black 
 , and crumbly Garden-Mould, that was efteemed 
 
 the bed fort, and had lain, for a Year, expofed to 
 the Atmofphere, without being exhaufted in Ve- 
 getation. 
 
 (2.) This Mould we elixated in fair and freffi 
 boiling Water, till all that was capable of diflbl' 
 ving therein was got out or extracted by the 
 Water, 
 
 (3.) Having thus obtained a Lixivium or So- 
 lution of our Subjedl, we filtred it thro’ thick 
 doubled Paper, in order to have it tranfparent, 
 and at lead free from any grofs terreftrial Parts, 
 that might otherwife lodge therein. 
 
 (4.) This Solution, therefore, contains all the 
 Parts of the Subjedt that are foluble in boiling 
 Water h). 
 
 (5.) To bring thefe Parts nearer together, that 
 they mighr manifeft themfelves to the Senfes, 
 and particularly to the Tafte, v/e exhaled away 
 the more aqueous Fluid in the Form of Vapour. ' 
 
 (6.) Then comparing the concentrated Solu- 
 tion, with a Portion of the former that re- 
 
 a) See Lebt. I. Exp. I. 
 
 b) SeeZfO?. J, Exp. 1. 
 
 mained . 
 
Of Earth. 6 1 
 
 mained unevaporated, we found it tafte mani- 
 feftly Wronger or more faline. 
 
 (7.) To gain a fuller Information, we evapo- 
 rated a Portion ftlll higher, and fet it to cry- 
 ftallize, if any Salt would fhoot a), 
 
 (8.) To a Part of the filtred Solution we ad- 
 ded Syrup of Violets, to djfcover whe- 
 
 ther the Solution was acid, alkaline, or neutral ; 
 and found it rather the latter h). 
 
 (9.) We wafhed the remaining terreflrial 
 Matter in feveral Waters, every time decanting 
 the upper muddy Liquor, after a little (landing, 
 in order to procure the pure Sand contained in the 
 Mould ; and found the Sand to be a large Pro- 
 portion of the whole. 
 
 8. This Experiment, or rather Combination 
 of Experin)ents, fhews us a Method of refolving 
 the matrix Earth of Vegetables into the confti- 
 tuent Parts thereof, without altering their natural 
 Form and Properties. Whence it fliould feem that 
 a true Judgment might be formed of Moulds, 
 both in general and particular, fo far as this Infor- 
 mation reaches, and a Rule be obtained for their 
 artificial Mixture or Compofition. Thus we find 
 the Mould under Examination contains a certain 
 Proportion of fine Earth, capable of being fuf- 
 pended in Water ; much more of a grofler hea- 
 vier Part that readily finks in Water \ perhaps a 
 little neutral Salt •, and a large Proportion of 
 Sand. Hence if this Mould had come from the 
 Ifland Ceylon., for inftance, having there ftrved for 
 the Growth of Cinamon, we might be directed 
 by this Analyfis to make or mix up a Mould that 
 fnould refemble it, with a View to produce Cinamon 
 
 *) The Succefs was not carefully noted. 
 
 h) See the Method of examining Mineral Waters^ in the 
 following Ledure, 
 
 ' in 
 
Lecture the Fourth. 
 
 in England. But to make the Experiment fuccefs- 
 ful, no Ids Regard muft be had to the State and 
 Ingredients of the Atmofphere, than to the State 
 and Ingredients of the Soil a). 
 
 9. To render the prefent Experiment more in- 
 ftrudive and ufefal, for dilcovering the Prin- 
 ciple of Vegetation, and the Nature of Earths 
 and Plants, it were proper to compare it with a 
 fiiiiilar Analyfis of certain vegetable Subjeds. 
 Thus by bruifing a tender Plant, elixating ail 
 its foluble Parts with warm Water, exhaling the 
 fuperfluous Moifture, and letting the Remainder 
 to cryflallize, we obtain the native faline part 
 of the Plant, in the form of a folid Salt, which 
 appears either of the tartareous or nitrous kind, 
 according to the Nature of the Plant b). 
 
 10. Tho’ any alkaline Plant, as CrefTes, were 
 v^^atered in its Growth with a Solution of Nitre, 
 which upon Diflillation affords much acid Spirit, 
 the Plant would ftill prove alkaline : and the fame 
 holds of every Plant and Salt hitherto tried c). 
 Whence there appears to be in Plants a Power 
 of changing any other Salt into their own. And 
 hence we find, upon Experience, that Compofls 
 abounding in Sea-Salt, Nitre, or urinous Salts, 
 all agree to promote Vegetation. 
 
 11. But as there may be certain more fixed 
 Parts naturally contained in Mould, than will 
 diffolve in boiling Water *, and as thefe Parts 
 may pofTibly be loofened, digefted, and rendered 
 capable of afeending into Vegetables, by the 
 
 a) SeeZ^^. Iir. 
 
 d) See M. Homberg cn the Nature of Vegetable Salts. 
 Memoir . de C Acad. An. 1699 . 
 
 c') I could wi(h the Experiment were tried with Sugar, Alum, 
 Pot-Alh, tAc. both in Alkaline and acid 'Vegetables. But 
 Care (hould be taken not to ufe too much of the Salts, which 
 in that Cafe would deftroy the Nature of the Mould. 
 
 long- 
 
Of Earth. 63 
 
 long-continued Adtion of the Sun and Atmo- 
 fphere •, it may be proper to try a more powerful 
 Analyfis of the fame Subjedt. 
 
 ExPE RI ME NT II. 
 
 ^he Analyfis of Garden Mould by Fire, 
 
 12. Having weighed two Pounds of the Fire, 
 
 kind of Virgin* Mould as was ufed in the prece- 
 ding Experiment, we put it into an earthen 
 Retort, and committed it to a naked Fire, 
 working by flow Degrees of Heat into a Glafs- 
 Receiver ^ and at lafl; keeping the Retort ignited for 
 fome time. There came over (i.) a Water ; (2.) 
 
 an Oil; and (3.) a volatile Spirit almofl: like 
 Spirit of Hartfliorn, or as if the Subject: had been 
 animal * ; and (4.) there remained behind a dry 
 Caput mortuum^ or apparently fixed and inert Earth. 
 
 13. We elixated Part of the Caput mortuumy 
 and then dried it; by Triture we reduced ano- 
 ther Part into one fimilar, homogeneous Pow- 
 der ; with a defign to put each Parcel into a (e- 
 paratq Pot, and expofe them to the open Air, 
 for a Year, to try whether they would then prove 
 fertile. 
 
 14. It appears by this Experiment, that our 
 Garden-Mould was of a Vegetable or Animal 
 Nature, in refpedt of the Salts or Juices it con- 
 tained ; and only Mineral, with regard to its fixed 
 Matter. In both which refpedls it greatly refem- 
 bles the natural Compofition of Animals and 
 Vegetables. And hence we fee the phyfical 
 Reafon, why animal and vegetable Subflances 
 
 * If it be fuppofed, that the CompoO, which might have 
 been ufed to this Mould, was not fufficiently rotted or chan- 
 ged, fo as ftill to retain its own vegetable or animal Na- 
 ture ; let the Experiment be repeated with Earth, which has 
 been known to have lain feveral Years fallow. 
 
 are 
 
64 
 
 Loam 
 made into 
 Clay. 
 
 Lecture the Fourth. 
 
 are proper Compods for Land. If we were to 
 enquire how Mould comes to be of this Nature, 
 it might in good Meafure appear from our for- 
 mer Doctrine of the natural Contents of the At- 
 mofphere *, which being animal and vegetable, 
 as well as mineral, continually fall upon the Sur- 
 face of the Earth. And hence Gardeners find a 
 manifeft Difference between the Soil of London 
 that of open Country Places, on Account of the 
 Quantity of Smoke daily precipitated out of the 
 Air upon the Gardens of London. And the like 
 is to be underftood of other Cities and Countries 
 refpe6tively. 
 
 i^. By comparing the prefent Procefs with 
 the fame performed upon a vegetable, an ani- 
 mal, and a mineral Subdance ; it appears that 
 one fimple fixed Earth is the Bafis of all animal, 
 vegetable, mineral, and earthy Matters *, or 
 the true Stamen^ Support, and Skeleton of Flefh, 
 Bone, Wood, Metals, and Earths, i^c. being 
 in itfelf of a fixed unalterable Nature. 
 
 1 6. We next proceed to Bolar F.arths^ which 
 feem divifible into two Species, according as they 
 are more or lefs tenacious ; in which view Lca 7 n 
 and Clay may reprefent them all. And even 
 thefe two feem only to differ in refpecSt of the 
 Finenefs or Coarfenefs of their component Parts, 
 which renders them more or lefs tenacious, ding- 
 ing, or adhefive. 
 
 Experiment III. 
 
 Lhat Finenefs of Parts in Earths may give Cohefion^ 
 Strength., and Solidity. 
 
 17. (i.) We mixed common Loam into a 
 Mafs with Water, and then dry’d it ; to lliew 
 that, compared with Clay, it would eafily break, 
 crumble, and fall into Powder. But (2.) beating 
 
 fome 
 
Of Earth. 65 
 
 fame Loam fine in a Mortar, and mixing it well 
 with Water, it clung like Clay ; and when dry’d, 
 adhered much more tenacioufly than before. 
 
 18. This Experiment not only fhews that Popery 
 Loam and Clay, or all the Bolar Earths, are hence im^ 
 nearly the fame thing, when their component pro<veahle. 
 Parts, or gravelly and fandy Matters, are redu- 
 ced to the fame Degree of Finenefs ; but alfo fup- 
 
 plies us with a Rule for the Improvement of Pot- 
 tery, and the Imitation of China Ware. This 
 Rule is to grind, or beat, the Earths employed, to 
 an extreme Degree of Finenefs : and accordingly 
 Porcellane has been imitated in Europe.^ by To- 
 bacco-Pipe Clay and other Earths exceedingly 
 fine ground, mixed into aPafte with Water, and 
 properly dried or baked. 
 
 19. The fame Experiment may likewife in- Farther 
 form us how Rocks are often produced, of dilFe- 
 
 rent Degrees of Hardnefs, according to the diffe- 
 rent Finenefs of the terreftrial Particles depofited 
 upon any Eminence, or Declivity, as walked 
 down by the Waters. 
 
 20. We recommend it to future Examination 
 how far this mechanical Tenuity of Parts may 
 reach, in caufing Strength and Hardnefs in Bodies : 
 and whether thofe two Properties are not diffe- 
 rent in Glafs, Cryftal, Diamonds, ^c. on Ac- 
 count of the different Finenefs of their Parts. *. 
 
 21. Under this Tribe of Bolar Earths we rank Bolar 
 all the hungry Garden-Earths, ali the landy 
 Field-Earths, all the Clay or Marly Earths, and 
 
 all the Mixtures thereof 
 
 22. We next proceed to Saline Earths*, hj Saline 
 which are meant all thofe wherein any Quantity of Farths. 
 Acid, Alkaline, or Neutral Salt is evidently con- 
 tained. 
 
 * Sec Mr. Boyle on Gems. 
 
 2J. If 
 
 F 
 
66 
 
 Lecture the Fourth. 
 
 23. If ftridt Examination were made, perhaps 
 no Earth would be found without fome Propor- 
 tion of Salt *, which has pretty generally been 
 thought the Principle that holds all Earths to- 
 gether. And there appears fome Reafon for the 
 Opinion, as we endeavoured to fhew by the fol- 
 lowing Experiment. 
 
 Experiment IV. 
 
 That a Saline Matter may give Tenacity and Firmnefs 
 to Earth, 
 
 ^ick~ 24. (i.) We flaked Quick-lime with a fufii- 
 lime depri- cient (^antity of Water to bring it into a Kind 
 
 Then fuffered the fuperfluous Moi- 
 fture to exhale gradually ; Upon which, (3.) the 
 Lime acquired a flony Hardnefs. (4.) We next 
 poured a much larger Quantity of Water upon 
 another Parcel of Quick- lime, than fufficed to 
 make it into a Pafte j then decanted the Water, 
 which tailed manifeftly faline. (^.) We after- 
 wards elixaCed the remaining Matter with feveral 
 Parcels of frefh Water, to get out all the Salt of 
 the Lime ; (6.) And now drying the Calx thus 
 deprived of its Salt, we found it would not hold 
 firmly together, but remained quite crumbly or 
 dufly. 
 
 Vjes eftbe 25. This Experiment Ihews us the Nature and 
 Expert^ Compofition of Lime, which, mixed with Sand, 
 mefif, makes the common Mortar ufed in Building. 
 We fee it is the Alkaline Salt contained in the 
 Lime, and either extricated or produced in cal- 
 cining the Lime-flone, that occafions the Mortar 
 to concrete and harden, And where the Salt is 
 in its full Proportion, the Lime is fliongefl, and 
 the Mortar hardefl and mofl durable. This fa- 
 line Principle in Lime is alfo that which gives it 
 the Advantage over Chalk, as a Compoft for 
 
 Grounds, 
 
Of Earth. 67 
 
 Grounds exhaufted or drained of their natural 
 Salt in Vegetation. For the Alkaline Salt of the 
 Lime) by ftrongly attradling the Moifture of the 
 Atmofphere, and other Particles that float there- 
 in, fweils, dilates, crumbles, and opens the 
 Earth with which it is mixed ; whence the At- 
 mofphere has the freer Action thereon, and in the ^ 
 mean Time the Alkaline Salt of the Lime becomes 
 of a neutral, or nitrous fertilizing Nature. 
 
 26. Under the general Head of Saline Earths ^heClafs 
 may be reckoned all thofe that are calcined or 
 burnt in the Fire ; as all the Kinds of Lime, Pot- 
 
 afli, Salt of Tartar, Soot, thefe being but 
 Mixtures of Salt and Earth : and to fay the 
 Truth, all Salts appear upon a rigorous Exami- 
 nation to be no other than Earths of different Na- 
 tures j which, when reduced to a certain Degree 
 of Subtility or Finenefs of Parts,- fo as perma- 
 nently to diffolve in Water, are then emphati- 
 cally denominated Salts. 
 
 27. The following Experiment regards the Sul- ^ulphu^ 
 phureous Earths, under which we reckon ail thofe 
 
 that will flame in the Fire; as Coal, Bitumen, 
 
 Sulphur, certain crude Ores, Marcafites, 
 
 28. By Marcafites we underftand all thofe Mi- Marcafites 
 neral. Earthy and Sulphureous Matters, that are ^hat! 
 otherwife called Pyrites^ Fire- Stones, Brafs- lumps, 
 Mundicks, or the like. For tho’ thefe may be 
 diftinguifhed in refped of lelfer Differences, yet 
 
 in general they are all a Compofition of Sulphur, 
 un- inflammable Earth, and a fmall Proportion 
 of Metal. 
 
 F 2 
 
 Expe R I- 
 
68 
 
 Lecture the Fourth. 
 
 Ex PE R IME N T V. 
 
 Analyfts of fulphnreous Earths hy an Example 
 in Mundick, 
 
 Mundick 29. We took half a Pound of Mundick re- 
 anahfcd. duced to fine Powder, and put it into an earthen 
 Retort, which being placed in a naked Fire, we 
 fitted on a capacious Glafs-Receiver, and luteing 
 the Jundure well with a Mixture of Loam and 
 Horfe-dung, we gave Degrees of Fire up to the 
 ftrongeft ; then letting all cool and taking off, 
 we found a fmall Proportion of an acid Liquor, 
 exafUy like the Spirit of Sulphur, made by the 
 Bell, at the Bottom of the Receiver, and a con- 
 fiderable Quantity of Flowers of Sulphur fublim- 
 cd to the Top. 
 
 30. The Caput mortuum being taken out, and 
 flux’d with half its Weight of clean Iron Filings^ 
 afforded a little Lump of a Metallic Subftance, 
 or Regulus. 
 
 Vfes of the 31. Hence we fee that Marcafitcs chiefly rc- 
 
 Expert- folve into Sulphur, and a more fixed earthy Part, 
 which being treated as an Ore yields a Pro- 
 portion of Metal. And hence perhaps all the 
 Pyrites, Brafs-Lumps, Marcafltes and Mundicks 
 are but cruder Kinds of Ore, and if they could 
 be brought to full Maturity, would prove real 
 .Ores. 
 
 Marcafltes 32. Thefe Marcafltes, upon long lying in the 
 fring. open Air, attrad the Moifture thereof, thence 
 grow hot, in fome Meafure diffolve, form an 
 Efflorefcence on their Surface, and by Degrees 
 turn into a Vitriol, of the fame Kind with the 
 Metal they contain Thus if that Metal were 
 Iron, the Vitriol becomes green or martial ; if 
 Copper, blue or cupreous. And on this is 
 
 founded 
 
Of Earth. 69 
 
 founded the Artificial Method of making Vitriol, 
 now pradifed in feveral Parts of England, 
 
 33. And from the heating, fuming, and firing Whence 
 of thefe Sulphureous Earths, by the Moifture o'i 
 the Air, we may perhaps learn the Origin of Hot ^nd Fires 
 Baths, Mineral Waters, Damps and Fires in /« Mines, 
 Mines. For it is found, that a Pile of thefe Sul- &c. 
 phureous Earths, being barely moiftcned, will 
 at firfi: fmoke, and at length take Fire, and burn 
 like glowing Coals a). 
 
 34. Our prefent Experiment likewife fhews us Honvexa- 
 a Way of examining thefe Marcafites, and of ex- niinedfor 
 cradling the Metal they may hold, after having firfi: 
 feparated tfidr Sulphur. Many fkilful Metaliiils 
 have been impofed upon by the fpecious Shew of 
 thefe' Marcafites ; for they ufually have a great 
 fpecific Gravity, and fome of them a greater thari 
 real Ores : whence again they may poffibly con- 
 tain the Matter of Metals, tho’ in a crude, im- 
 perfedl, or unfixed State. But to bring this Mat- 
 ter to the Tefi:, and to try the Validity thereof, re- 
 quires more than a common Knowledge in Me- 
 tallurgy h). 
 
 Our next Species of Earths is the Stony. 
 
 Stony 
 
 Earths, 
 
 Experiment VI. 
 
 ^hat Ignition may dejiroy the tenacity or Cohejion of 
 Stony Earths,, /hewn in Alabafter, 
 
 (^-) We reduced two Pounds of Alabafter Alahafler 
 to fine Powder ; then put it into a flat Iron Pan, caUinA, 
 
 a') See Dr. Power's Experiments, page 63, 
 
 A fmall Proportion of Silver has been obtained from cer- 
 tain Kinds of Mundick, after the Mundick had been'fluxed 
 \y|rh iron Filings, aiad brought to a Regulus. 
 
 F j ancj 
 
rf the 
 Experi- 
 ment. 
 
 Lecture the Fourth. 
 
 and apply’d a foft Heat, that the Matter might 
 not glow, yet remain too hot to be touch’d. The 
 Powder was thus brought to flow or run like 
 Qinckfllver, and being gently ftirred, to boil and 
 bubble. VVe let it continue thus, with a fof^ 
 Heat, till it would run off a Spatula held almoft 
 horizontal ; then removing it from the Fire, it 
 grew cold, and was put into a Glafs, kept clofe 
 Hopped and fee in a dry Place, under the Nam,® 
 of Gypfum., or calcin’d Alabafter. 
 
 (2.) A Parcel of the Gypfum thus prepared 
 being brought into a pappy Confidence with Wa- 
 ter, the humid Mafs became fo hard and rigid, 
 in a Quarter of an Hour,' as to ring, or afford a 
 clear Sound, when ftruck with the Finger, or any 
 more folid Inflrument. 
 
 (3.) But a Parcel of the fame Powder being 
 kept in a State of Ignition for fome time, before 
 it was taken out of the calcining Pan, and then 
 mixed with Water, acquired only a loofe, friable 
 Confiftence, or a much lefs Degree of Hardnefs 
 and Tenacity than the other. The un-ignited 
 Sort alfo, by being kept in the open Air, lofes 
 of its coagulating Virtue ; and when once confo- 
 lidated with Water, becomes unfit for the like 
 Purpofe again. 
 
 36. Thus all the Stony Earths that do not vi- 
 trify in the Fire, are by Ignition reduced to fine 
 Powder. So may Flints themfelves, by being 
 often ignited and quenched in Water. And thus 
 white Marble orCryftal is reduced to a Powder, 
 fit for the making of pure white Glafs. 
 
 37. This Experiment alfo fhews us an earthy 
 Matter, apparently fluid over the Fire, that 
 wfill harden jn Water, and ferves to diredl a far- 
 ther Enquiry after cheap Bodies, that will grov/ 
 llili harder 
 
 r Watery which might be of 
 
 Servieg 
 
Of Earth. 7 1 
 
 Service in Bridge-works, Water- works, and the 
 like a). 
 
 38. The prefent Ufe of the Preparation is fuf- 
 ficiently known, for taking off Faces, Impref- 
 fions and Figures, and the Hopping of leaky 
 Pipes, or Veffels that tranfmit or contain Water. 
 
 39. The fixth Clafs is that of Metallic Earths: ’^^talUc 
 For there are fome Reafons to judge, that even 
 Metals themfelves are but a Species of Earths h ) , 
 
 as they both burn into Afhes, and melt into 
 Glafs j whilft their metallic dudile Form feems 
 owing to nothing more than a certain Pro- 
 portion of Sulphur or Oil contained in them ; 
 which being burnt out, leaves them terreftrial 
 Calces, or certain Metallic Earths, of a nature 
 peculiar to each Metal c), 
 
 40. And thus we may divide Earths into two Earths re- 
 general Tribes, viz. the Brittle or Friable., and the 
 Dubiile or Malleable. We have gone thro’ the 
 Friable Species and (hall profecute the Dudile 
 hereafter, in our Lectures upon Mineralogy and 
 Metallurgy. 
 
 Axioms and Canons. 
 
 I. We learn from the foregoing Enquiries, that 
 the Atmofphere, with its Contents, is a chief In- 
 ftrument in promoting the Fertilization of the 
 Earth, whereby all Vegetables, and thence all 
 ' Animals are fed, fupported and maintained d ) ; 
 that this Mould may in fome Meafure be fup- 
 
 «) See Mr. Boyle'^i Philofophical Works, Abridg. Vol. I, 
 330> 331- 
 
 E) See Becher^s Ehyjica Juhterranea paffira. 
 
 <r) See StahPs Comment, on Becher'^s Phyfica fuhterranea ; 
 
 alibi pajjtm. 
 
 ti) See Lett. III. pajjim. See alfo the prefent Lett. Exp. I. II. 
 
 F 4 plied 
 
72 
 
 Lecture the Fourth. 
 
 plied by the Air, at different times , and after** 
 wards by lying immediately under the Turf, re- 
 ceive whatever Richnefs or fine Matter defcends 
 from above, in the Form of Dews, Rains, Snow, 
 Hail, or other more fubtile Conveyance ; and that, 
 this invigorating Subfiance foaking thro’ the 
 upper Turf, may be thereby defended from the 
 Winds and beating Sun, as by a Skreen, from be- 
 ing exhaled too foon again. And thus the At- 
 mofphere exercifes a Kind of renovating Power, 
 fo as to fupply even exhaufled Earths with frefh 
 Vigour, and fit them for the Produdion of new 
 Crops b). Whence we have a good Rule for re- 
 novating and recruiting fhrunk, withered, and ex- 
 haufled Vegetables, by expofing them to a kindly 
 Atmofphere, rather than by barely watering 
 them ; which might only ferve to corrupt and 
 fpoil them the fooner! 
 
 2. That fome capital Rules may be formed 
 for the Improvement of Agriculture, Horticul- 
 ture, and the raifing and improving of Fruit and 
 Forefl Trees, by finding the Nature, Compo- 
 fition, and Ingredients of the Soil wherein each 
 Kind of Grain, Plant and Tree, is mofl de- 
 lighted r.) 
 
 3. That it is poffible, by rational Experiments, 
 to find the befl Kinds of Steepings for Grain and 
 Seed, and the befl Kinds of Compofcs and Ma- 
 nure for Land according to the Nature or pre- 
 fent Exigence of the Soil, or the Fruit intended 
 to be produced *, or any one particular Salt, Oil, 
 or Property to be introduced, either into thq 
 Ground or Seed c). 
 
 a) See LeSi. UI. 
 
 y) See Le^t- IIL and the prefent, under Exf. I, h II. 
 
 See iix/). ) II. 
 
 4. That 
 
Of Earth. 
 
 4. That Water, as well as Fire, may be an 
 ufeful Chemical Analyfer in fome Cafes a ). 
 
 5. That all vegetable and animal Subftances, 
 Excrements, naturally change and become 
 Compoft, and at length Mould j whence there 
 is a continual Reciprocation between the animal 
 and vegetable Kingdoms, which thus conti- 
 nually pafs into one another, by the Mediation 
 of the Atmofphere, Heat, and other natural 
 Agents h). 
 
 6. That Compolls, before they can produce 
 their Effedf, muft in fome Degree approach the 
 Nature of the Soil they are defign’d to im- 
 prove c), 
 
 7. That by Earths are underftood fuch grofs 
 Subllancesias are of themfelves infoluble in Water, 
 and indeftru6lible in the Fire, yet with fixed Al- ' 
 kaly melt into Glafs, or with any undluous 
 Matter affume the Form of a Metal, according 
 to their refpedlive Natures d) ; and confequently, 
 that even Earths, tho’ apparently exhaufted fimple 
 Bodies, have yet their refpedive or peculiar Pro- 
 perties and EfFed:s e), 
 
 8. That the moft fixed Part of Earth has ma- 
 ny Inftrumental Efficacies, not only as floating 
 in the Air, and as forming the Bed or Matrix of 
 Vegetables *, but alfo in conftituting the folid 
 Parts or Stamina of all vegetable, animal, and 
 mineral Subftances /), and affording us all our 
 VeflTels of Glafs, Stone, Wood, Metal, our Fur- 
 naces, Crucibles and Tefts, and being perhaps 
 
 fi) See Exp I. 
 
 b) See Le^. III. & Exp, I. II. of the prtfei>|. 
 
 f) See Exp, I. k. II. 
 
 a) Sec all the Experiments, 
 e") vSee above, § 5, 26, 38. 
 
74 
 
 Lecture the Fourth. 
 
 in itfelf the moft fixed and unchangeable Body iij 
 Nature a). 
 
 9. That a high Degree of Trituration, or re- 
 ducing the Particles of certain Bolar Earths, 
 Clays, and ftony Earths to an extreme Finenefs, 
 may contribute to the Improvement of the Art 
 of Pottery. For which Purpofe, Trituration, 
 Sifting, Subfidence in Water, and Decantation, 
 might be ufed to advantage i?), 
 
 10. That the making of Lime may be im- 
 proved for the Purpofes of Building, Manure, 
 and Water-Works, by a due Choice of the Ma- 
 terials, and a fuitable Calcination c). 
 
 11. That fome confiderable Ufe and Improve- 
 ment might, with proper Skill and Application, 
 be made in the Bufinefs of Marcafites and Mun- 
 dicks ; Bodies ufually efteemed as Refufe, and 
 intradable Stuff d), 
 
 12. That Marcafites, by attradmg the Moi- 
 fture of the Air, may be the efficient Caufe of fub- 
 terraneous Fires, hot Springs, Damps in Mines, 
 Mineral Waters, d), 
 
 15. That the Matter of Metals may poffibly 
 lie loofe, immature, or unconcoded in certain 
 Mineral Matters, fo as in the Fire to fly away 
 with the Sulphur, or other Parts of the Mineral ; 
 unlefs detained, and brought to greater Perfec- 
 tion either by Nature or Art d), 
 
 14., That Fire may have the fame Effed as 
 Air or Time, on certain ftony Matters, and 
 ^lake them loofe, crumbly, and incoherent e), 
 
 а) See § 15. 
 
 б ) See Exp. Iff, 
 
 c) See Exp. IV. § 25. Exp VI. § 3^. 
 
 d) Exp. V. 
 
 e) Exp. V'. & § 35. 
 
 LEG- 
 
[ 75 ] 
 
 L E C T U R E V. 
 
 CONTAINING 
 
 ^ Natural and Chemical Examination of 
 Waters, 
 
 I. prefent Bufinefs is the Chtmicdl The Suh- 
 
 I J Examination of Waters ; with a view><^?- 
 to manifeft their Natures, their Ufes to 
 the Earth, and all vegetable, animal, and mine- 
 ral Subftances ; but particularly to Man, fo far 
 as we can difcover them. 
 
 2* By the general Name of Water we under- Water de^ 
 ftand.an extremely fluid, limpid, infipid, andA^^* 
 inodorous Liquor. This Definition is obvious, 
 and taken from the dire6t Teftimony of the 
 Senfes ; but by enquiring phjlofophically into the 
 Nature of Water, we fhall find it pofTelTed of 
 many unexpected Properties. 
 
 Experiment I. 
 
 That Water is contained in many folid and^ to ap- 
 pearance^ dry Bodies. 
 
 3. We took a Piece of the hardefl: and dryefl: Found in 
 Bone we could procure, and diftilling it in an 
 Earthen Retort with Degrees of Fire, obtained 
 a very large Proportion of Water, along with 
 much Oil, and volatile Salt 
 
 * See this Experiment farther profecuted in Le£i, VIII, 
 
 Fxp. II. 
 
 4. This 
 
76 
 
 Lecture the Fifth. 
 
 4. This Experiment holds true even of the 
 oldeft Hartlhorn^ the dryeft and hardeft Woods, 
 Earths, and pulverized Stones. Whence if ap- 
 pears, that Water may lie concealed in folid Bo- 
 dies, and make a conftituent Part thereof; as we 
 formerly fliew’d of Air a). For we do not here 
 mean that Water infinuates itfelf into the fuper- 
 ficial Pores of Bodies, as Wood, Skins, Leather, 
 Parchment, Strings, &c. fo as to fwell them in 
 moift Weather, and leave them fhrunk in dry ; 
 but that it remains permanently intermixed as 
 an efTential Ingredient, or Part of folid Bo- 
 dies, as in Stone, or Brick after baking, 
 
 Of this we gave an eminent Inftance in our laft 
 Ledlure b), where we fhew’d that Gypfum^ with 
 Water, prefently concreted to a ftony Hardnefs. 
 
 5. If any doubt fhould arife, whether the Li- 
 quor obtained from the Bone in our Experiment 
 be truly aqueous, we might fhew it to Satisfadion, 
 by feparating the Oil, and turning all the volatile 
 Salt contained therein to Sal-Ammoniac, by 
 Means of a fufficient Quantity of Spirit of Sea- 
 Salt ; then redifying the Liquor by repeated Di- 
 ftillation, and bringing it over in Form of a pel- 
 lucid, infipid, and inodorous Fluid c), 
 
 6. It 
 
 ; Lea, III. Exp. X. 
 h) Exp.w. 
 
 cj To purify this Liquor abfolutely, is a very laborious Talk; 
 but as fome of the firft Drops come over limpid, and almoft 
 infipid, ber'bre the Oil and Salt begin to rife, this may af- 
 ford a ftrong Sufpicion that the fucceeding Drops are alfo 
 aqueous, only mix'd with Oil and volatile Salt. For tho' the 
 Bone were ever fo thoroughly dried by the Fire, and the 
 VelTels employ’d ever fo free from Moiilure, a large Propor- 
 tion of the aqueous Liquor would ftill be obtained. Befides, 
 the foul and fetid Liquor has been fo far cleared from the 
 volatile Salt and Oil, as to appear limpid, and prove infipid. 
 
Of Water > 77 
 
 6. Ic is therefore certain, that all Vegetables, 
 and even the moft folid Parts of Animals, natu- 
 rally contain a large Proportion of aqueous Pluid, 
 or adual Water, in their Compofition ; and that 
 it remains in them unaltered in its own Nature, 
 fo as, when fet free, to refume the Form of Wa- 
 ter, after having been detained, or circulated 
 therein for numbers of Years. Whence it fhould 
 fcem, that Water pafles thro’ all Natural Bbdies, 
 unchanged either by Accretion, Growth, Appo- . 
 fition. Fermentation, Putrefadion, Digeftion, 
 Diftillation, being chemically recoverable 
 again from Vegetables and Animals, Wines, 
 Vinegars, and Spirits. 
 
 ExPE R I ME N T II. 
 
 *That JVater may be collefled from the dryeft Ah\ 
 or in the hvtteft Climate, 
 
 7. (i.) We put half a Pint of common Water h the dry- 
 into a cylindrical Glafs, wiped perfectly dry on Mr, 
 the Outfide ; then added to the Water, two 
 Ounces and three Quarters of pulverized and dry 
 Sal-Ammoniac. We now ftirr’d them brifkly to- 
 gether ; whereupon the Water floating in the ex- 
 ternal Air was, by the Coldnefs thus produced 
 
 as the Salt diflblved within, condenfed on the 
 Outfide of the Glafs, and trickled down in fmall 
 Veins into the fhallow Bafon fet underneath to 
 receive it. 
 
 and inodorous. And as it approached nearer to common 
 Water, after every Rectification, there is no doubt but, if a 
 fiifficient Quantity were procured, it might by Degrees be 
 brought exactly to refemble common Water, diftilled and 
 treated in the fame Manner. But the eafieft Way is to im- 
 pregnate common Water with the Oil and Salt of the Bone ; 
 fo as to make it refemble the Mixture that comes from the 
 Bone into the Receiver upon Diftillation. See more to this 
 Purpofe in Le^. VIII. Exp, I. <5 14. 
 
 8. This 
 
78 
 
 ^he Expe 
 riment 
 extended 
 and op“ 
 plied. 
 
 Lecture the Fifth. 
 
 1. This Experiment holds in all Climates and 
 Places, of whatever Heights, where it has been 
 tried. Whence, by the Law of Indudion, we 
 may make it univerfal, till any contradidtory In- 
 ftance appears. Thus therefore it may hold in 
 the moft parched Countries and hotteft Seafons, 
 fo as to afford an agreeable Method of cooling 
 potable Liquors, and rendering them morerefrefh- 
 ing. For if the Glafs containing the Salt and 
 Water be fet in any Liquor, the Liquor will be- 
 come cooler as the Salt diffolves. And if any 
 confiderable Improvement could be made in the 
 Contrivance, it might ferve in fome Meafure to 
 fupply the thirfly Traveller in parched Defarts, 
 and Sailors with frefh Water at Sea : nay, it has 
 been a Pradlice among the latter to hang out 
 Fleeces of Wool on the Sides of the Ship over 
 Night, and to fqueeze frefh Water out of them 
 in the Morning. 
 
 9. The fame Experiment, being carried higher, 
 affords us a Method of procuring a Degree of 
 freezing Cold, in the hotteft Countries, at all 
 Seafons of the Year. For if a Quantity of dry 
 and pulverized Sal-Ammoniac be feparately in- 
 cluded in one well-clofed Glafs, and a proper 
 Quantity of common Water in another, and if 
 both thefe Glaffes be put into the firft Solution, 
 whilft the Salt is diffolving, both the confined 
 Salt arid Water will foon acquire the fame De- 
 gree of Coldnefs as the firft Solution ; and being 
 then taken out, and mixed together, they will 
 form a fecond Solution much colder than the 
 firft. And thus by repeating the Experiment 
 twice or thrice, with frefh Salt and Water, a 
 Degree of freezing Cold may be foon obtained 
 in the hotteft Climate. 
 
 E X P E R I- 
 
Of W ater. 
 
 Experiment III. 
 
 That an Earthy Subjlance is naturally contained in 
 Water, 
 
 10. (i 0 We filled three fcveral Glafles with pure 
 
 Rain Water, Spring-Water, and Water, 
 
 and let them ftand clofe covered for fome Days 
 before they were exhibited : there was an earthy 
 Sediment then depofited in all three, but moft in 
 the Thames -^ the Seditnent whereof was 
 not only larger, but alfo more foul and muddy 
 than in the Rain-Water; tho’ here alfo it was 
 dirty, perhaps becaufe not carefully colledcd : 
 whereas in the Pump-Water, it was white, fcaly, 
 flaky, and fhining, like fine Spangles of Talc, 
 
 11. This Experiment alfo is univerfal, fo far 
 as it has been tried with Care, and holds true of 
 the Waters of all Species and all Countries ; 
 particularly in thofe called Mineral Waters, from 
 which an earthy Subftance may ufually be preci- 
 pitated by Art, in a confiderable Proportion : 
 For Example, by the bare Addition of Salt of 
 Tartar. 
 
 12. Certain Experiments carefully made, and 
 repeated, Ihew that the terreftrial Matter natu- 
 rally contained in Water, has a principal Share 
 in the Growth and Increafe of Vegetables ; all 
 the Plants that thrive in Water, appearing to en- 
 large their Bulk in Proportion to the earthy 
 Matter furnifhed by the Water. Whence pure 
 Elementary Water feems but a Kind of Ve- 
 hicle to convey this nutrimental or fubftantial 
 Part, and depofite it in the Veflels through which 
 the Water moves, in order to its general Exit at 
 the Surface of Vegetables Yet we are not here 
 
 * See Dr. Wood-ward^ Experiments to this Purpofe, in the 
 Philofo^hical Pranfaokns, 
 
 79 
 
 Water 
 
 cemtains 
 
 Earth, 
 
 tQ 
 
8o 
 
 Lecture' the Fifth. 
 
 to exclude the Inftrumental Efficacy of the two 
 other Elements, Fire and Air. Now this appear- 
 Office and Jng to be the general Office of Water, in the whole 
 Vegetable and Animal Kingdoms, viz. the Con- 
 veyance or Diflribution of the alimentary Matter 
 to all their Parts, it may be proper to confider 
 its Phyfical Properties, which wonderfully fit it 
 for this Office. 
 
 13. The Figure of its component Parts ap> 
 ties pc^rs to be fmooth and fpherical, like thofe of 
 
 Quickfilver, whence it becomes extremely move- 
 able and penetrating. Thus it readily enters the 
 Pores of Wood, Leather, Skins, Chords, Mufical 
 Strings, ^c. and thus it likewife becomes ca- 
 pable of moving and agitating Particles of Mat- 
 ter lefs a6live than itfelf, and fo proves the more 
 immediate Phyfical Agent of Fermentation, Pu- 
 trefadlion. Solution, And thus it alfo con- 
 
 veys earthy and faline Matters thro’ our Filtres of 
 Paper, Stone, ^c. and even raifes fome Propor- 
 tion of them in Diftillations. 
 
 14. Its Particles likewife appear to be ex- 
 tremely minute, and fo to have a large Share of 
 Surface. Hence Water is admirably^ fitted for a 
 Solvent, or for readily entring the Pores of Salts, 
 and coming into full Contad with all their Par- 
 ticks. And thus it will pafs, where Air cannot, 
 on Account of its Moiflure, or lubricating 
 Power, whereby it foftens mucilaginous Matters, 
 and will therefore foak thro’ the clofe Pores of a 
 Bladder. And being thus qualified, it feems ex- 
 tremely well fitted to enter or flide thro’ the fine 
 
 ' Canals and Vefiels of Plants ; fo as to convey 
 nutritious, faline, or earthy Particles along with 
 Itfelf ; and having depofited them by the Way, 
 and being now robbed of all that is ufeful to the 
 tndivkluais, it at length perfpires into the open 
 Armofphere, in order to be there recruited and 
 
 fitted 
 
of Water. • , 8i 
 
 fitted for frefli Service. And the fame kind of 
 Office it performs in Animal Bodies. 
 
 15 . Hence we may learn the phyfical Reafon ihatofRi- 
 why River- water is more fertilizing than Rain, 
 
 viz. becaufe it contains more earthy Matter •, 
 and why fuch Meadow and Failure Lands, as 
 lie commodious to be overflowed by muddy 
 Rivers, yield greater Crops than fuch as are 
 watered by other Means. Hence the incredible 
 Fertility of Egypt appears to proceed from the 
 turbid Overflowing of the Nile., and the fame is- 
 to be underflood, in fomeDegree, of other Rivers, 
 as the Ganges the 'Thames^ &c a). 
 
 Experiment IV. 
 
 "That Water faturated with one Body will (till dlf- 
 folve another. 
 
 16. (i.) We took four Ounces of pure cold fyd'tJJoU 
 Rain-water, and diffolved therein as much dry 
 common Salt, reduced to Powder, as it would Rower of 
 take up. The Salt ufed being Part of a known 
 Quantity, we weighed the Remainder, to find 
 precifely how much had been employ’d, and 
 
 found it about an Ounce-, which therefore gave 
 the Meafure of the Power that the Water had to 
 diflTolve common Salt, with the Degree of Heat 
 then prefent in the Atmofphere. To this fatu- 
 rated Solution of Sea-Salt we added about' two 
 Scruples of dry pulverized Nitre, and found 
 that itdiflTolved therein, tho’ no more common 
 Salt could be taken up by the Vv ater. 
 
 17. This Experiment is only particular-, for 
 the dilTolving Power of Water is different on 
 
 a) See Boyle'*s Abridgment. Vol. I. fag. 248. and . 
 
 Lowthorf s Abridgment of the Philofophical Tranl'aflioris, 
 
 Vo\. ll. pag. 
 
 G 
 
 different 
 
82 
 
 Lecture the Fifth. 
 
 different Subjefts a). Whence a Set ofExpcri- 
 ments fhould be ma'^c, to fhcw this Power on 
 all the Salts, and other SubjecSis, whether mu- 
 cilaginous, gummy, earthy or others, that arc 
 capable of diflblving in Water. Such a Set of 
 Experiments might prove of confiderable Ufe in 
 phyfical and chemical Enquiries, and help to 
 redlify the Mind, which is extremely apt to 
 form general Rules from a few particular In- 
 ftances. Whence Water has often paffed for a 
 Kind of univerfal Solvent tho’ there are nume- 
 rous Bodies which it will not difiblve b). And 
 from this erroneous Notion of a general diflblv- 
 ing Power in Water, the Enquiry into Mineral 
 Waters has been in great Meafure either flop- 
 ped, or perverted c), 
 
 1 8. The limited Power which Water has, of 
 diflblving common Salt, appears remarkably in 
 the Ocean ; which we fee, by our Experiment, 
 may naturally contain about one fourth Part of 
 fuch Salt ; or, with an additional Heat, confide- 
 rably more; tho’ its Charge is always limited by 
 the Nature of the Thing, and cannot be above 
 one certain Proportion. This, however, is 
 found to differ in different Seas, or Bays ; the 
 Water of fome being found to yield more Salt 
 than others, according to the greater Heat or 
 Exhalation of Vapor in thofe Seas or Bays ; or 
 again, perhaps, according to the Opportunity 
 which the Water has had of running upon a more 
 faline Bottom 
 
 19. But when Water has diflblved its full 
 Proportion of common Salt, we fee, by the 
 
 . a) As will appear hereaFter. LeH. VI. Exp. T. 
 
 As Stones, Metals, Glafs. Gems, Amber, Shells, Coral, 
 Sponge, Cloth, See hereafter Le 6 i. VI. §. 15. 
 
 c') See the appendix to Ks-jj Experiments and Qhjer^ationi 
 upon Mineral Waters^ lately publiihed. 
 
 Experi' 
 
of Water. 83 
 
 Experiment, that it may ftill diflblve fome 
 Quantity of another Salt. And how far this 
 Power may extend, as to the Matters at the fame 
 time diflblvable in Water, has not been hitherto 
 fufiiciently afcertained a). 
 
 20. Nor is the Method, wherein different 
 Salts range themfelves in the fame Water, pre- 
 cifely determined. That they do not intermix, 
 fo as inextricably to entarigle and confound their 
 Particles among one another, appears from 
 Cryftallization. For if feveral different Salts 
 be diffolved together in the fame Parcel of Wa- 
 ter, they may be made to (hoot feparately out of 
 it again, by repeated Evaporation and Cryftai- 
 lization, each in its own natural Form and Fi- 
 gure, or pure and unmixed with the reft. But 
 the Power of Water as a Solvent will again come 
 to be confidered in our next Le 5 iure upon Men^ 
 
 Jiruums b). 
 
 Experiment V. 
 
 *the natural Ingredients or different component Parts 
 of Water, 
 
 21. (i.) We took a Pint of the pureft 'R.dXn- The Con^ 
 "Water, decanted from its natural Sediment, and tents of 
 put it into a bellied Glafs, with a long flendef 
 Stem ; then marked the Part of the Stem to 
 which the Water rofe, and fet it in the exhauft- 
 
 ed Receiver, where we found it manifeftly ex- 
 panded, and difeharged many Bubbles of Air. 
 
 (2.) We put the fame Water into a clean Glafs 
 Retort, and diftilling with a gentle Heat into a 
 Glafs-Receiver, there came over a pure light 
 Water, or merely aqueous Liquor j leaving a 
 
 a) See Dr. Gre-io and Bofe P'lfjim, 
 
 /»} See Leii, VI. E^. 1, 
 
 G 2 
 
 fmall 
 
84 Lecture THE Fifth. 
 
 fmall Quantity of dry and whitifh terreftrial Mat- 
 ter behind. 
 
 22. This Experiment requires a farther, and 
 much more exad Profecution. We fee it re- 
 folves Water into three diftind, and, to appea- 
 rance, different Parts; viz, (i ) Air, (2.) ele- 
 mentary Water, and (3.) Earth. The Truth of 
 this Analyfis feems confirmed by other Experi- 
 ments. For Water, by boiling, is alfo deprived 
 of the Air it naturally contains. And fo it like- 
 wife is by ftrong Freezing, the Ice becoming 
 gradually lefs porous, and more purged of its 
 Air-Bubbles ; alfo Water upon thawing always 
 leaves a Quantity of earthy Sediment behind. 
 But neither this Experiment of Freezing and 
 Thawing, nor the Re-diftillation of Water, has 
 been carried fo far as to fhev/, with Certainty, 
 whether any, and what Proportion of the Water 
 is thus adually convertible into Earth; or whe-- 
 ther a Quantity of earthy Matter, before difiblv- 
 ed or finely difperfed in the Water, is thus only 
 aggregated, or colleded together and left be- 
 hind, in a dry, folid, or earthy Form, upon 
 Evaporation. 
 
 23. The Determination of this Point is of 
 Confequence to Fhyficks. The Circumftances 
 that tend to invalidate the Experiment by Di- 
 flillation are, (i.) That the Water fuffers a great 
 Diminution of its Quantity in the Operation ; 
 fome Part flicking to the Sides of the VefTel^ 
 employed every Time, and fome tranfuding thro* 
 the Luting : whence the Account is defrauded. 
 And (^2.) that in tranfvafing the Liquor, it every 
 Time licks up the Dufl naturally contained in the 
 Atmofphere, and at the fame Time lofes Particles 
 of Water, which are thus carried off by the Air ; 
 whence, upon numerous Repetitions of the Ex- 
 periment, a large Proportion of the Earth ob- 
 tained 
 
Of Water. 85 
 
 cained may proceed from the Dull of the At- 
 mofphere a)» ^ 
 
 24. The Experiment by Congelation feems 
 attended with fewer Difficulties, and might per- 
 haps be brought to determine the Point with lefs 
 Exception, by ufing a Circle of Freezings and 
 Thawings, alternately repeated, with Care to fe- 
 parate the Earth each Time. 
 
 25. What we here term Elementary Water, is 
 the pure aqueous Part which comes over in Di- 
 ftillation, commonly called by the Name of 
 diftilled Water. This diftilled Water is found 
 to be lighter and purer than the natural ; pro- 
 vided it acquire no Foiilnefs, or heterogenous 
 Parts in the Operation, And it is obfervable 
 that, if the Operation be flopped in the Middle, 
 a groffer Water remains befiind than what came 
 over. Whence, for all curious chemical and 
 ceconomical Ufes, the Water employed fhould 
 not boil too long; as particularly in the making 
 of Tindlures, Tea, Coffee, 
 
 Experiment VI. 
 more commodious Methods of examining Water » 
 
 26. By Means of the Inffrument called the Common 
 Hydroftatical Balance, we took the fpedfic Gra- Water 
 vity of the Water propofed, and diredlly judged 
 
 of its Goodnefs by its Lightnefs. 
 
 27. This Experiment is a good Subftitute for 
 feveral other Ways of examining the Purity and 
 Goodnefs of Waters, both common and mine- 
 ral. For it appears by numerous Inftances, that 
 light Waters are, Cceteris paribus^ the beft, pureft 
 and wholefomeft. 
 
 a) See Mr. Boy'e\ Philofophical Works, and Boerhaa^ve^s 
 $,heiniftry. 
 
86 
 
 Lecture the Fifth. 
 
 28. But as the prefent Method requires the 
 Ufe of a curious Inilrument, and a confiderjble 
 Degree of Accuracy and Attention, other more 
 expeditious, tho’ not more exadf. Trials have 
 been invented j particularly by the Ufe of Water^ 
 Poifes *, which arc Inftruments of Ivory, Glafs* 
 
 made hollow-bellied, fo as to float in Wa- 
 ter, higher or lower, according as the fpecific 
 Gravity thereof is more or lefs ; And the in- 
 ftruments being graduated or divided by Lines 
 on the Stem, readily (hew to the Eye the 
 Difference betwixt the fpecific Gravities of 
 any two Waters propofed j tho’ not with the ut- 
 moft Exadlnefs. 
 
 29. The Foundation of both Experiments is 
 this, that the Bodies diiTolved or licked up by 
 Water, in its pafling thro’ the Caverns, or fuper- 
 ficial Parts of the Earth, are generally either fa- 
 line or earthy; which being both more ponde- 
 rous than pure Water, it follows, that the ligheft 
 Waters are leaft impregnated with them, and 
 therefore fitteft for the finer Ufes, where no fuch 
 grofs, faline, or earthy Matters are required ; as 
 they are not particularly in the healthy human 
 Body, where the ordinary Office of common 
 Water is to convey and diftribute Nutriment to 
 all the Parts, to dilute and wafh off the Over- 
 proportion of animal Salts, as it evidently does in 
 Sweat and Urine. 
 
 30. By Means of the prefent Experiment we 
 find, that the pureft Rain-Water is of nearly the 
 fame fpecific Gravity with diftilled Water; nei- 
 ther of them, when obtained pure, precipitating 
 any grofs earthy Matter upon the Addition of 
 Oil of Tartar pr deliauium^ as many Spring- 
 Waters do. 
 
 31. Common-Waters are diflinguiflied into 
 Hard and Soft^ and accordingly are ufed for dif- 
 ferent Operations, Thus foft Water is found beft 
 
 for 
 
of Water. 8 7 
 
 for extra^llng certain 'l'in6lures freeing Metal- 
 lic Calces from their Salts, ^c. And hard Wa- 
 ter is beft for the tem.jering of Steel, the mak^ 
 ing of artificial Wines, and Malt-Liquors in- 
 tended for long keeping. 
 
 3 2. Hard ¥/aters are fuch as contain a foreign, 
 faline or terreftrial Matter; and accordingly be- 
 come fofter by long (landing, or by a fmall Ad- 
 dition of Salt of Tanar; both which tend to pre- 
 cipitate the terreftrial Subftance out of them. 
 
 Experiment VII. 
 
 "The more commodious Methods of examining Mineral 
 Waters, 
 
 33. (i.) To half a common Wine-Glafs Mineral 
 Tyrmont Water we added a Dram of the Syrup Waters 
 of Violets, whereby a greenilli Colour was pro- 
 duced. (2.) To a like Qtiantity of the fame Wa- 
 ter we added a few Grains of feraped Galls; and 
 
 firft, a purple, then a blackiih Colour prefently 
 enfued. (3.) We evaporated a Quantity of the 
 fame Water, and a fmail Proportion of an ochry 
 Subftance was left behind. (4.) We fet a Glafs 
 of the fame Water, cold, in the Receiver of the 
 Air-Pump, and found, upon with-drawing 
 the Air, that the Water fparkled violently, 
 and difeharged a numerous Qiiantity of fmall 
 Bubbles at its Surface •, like what happens in the 
 Conflid of an acid and alkaline Liquor. 
 
 34. This Experiment holds in all the Cafes of 
 Chalybeate Waters only, and not of Mineral Wa- 
 ters in general. By Mineral Waters, in general, 
 are meant all thofe wherein any Medicinal Vir- 
 tues, befides thofe of common Water, are found. 
 
 Thefc Mineral Waters are of various Kinds : 
 we may confider them under the general Titles 
 ©f Chalybeate^ Purgative., and Alterative, 
 
 G 4 35. The 
 
88 
 
 Lecture the Fifth, 
 
 35. The more ufeful and commodious Addi- 
 tions for examining thefe three Kinds of Mineral 
 Waters, are. Galls ^ Syrup of Violets^ and Oil of 
 Tartar per deliquium. 
 
 36. Galls tv in them any fmall Propor- 
 tion of Vitriol or diffolved Iron*, as having the 
 Property of immediately ffriking a purple, or 
 black Colour, in all Waters, where any fuch 
 Subftance is lodged. 
 
 37. Syrup of Violets in the fame Manner difco- 
 vers any fmall Predominancy of an Acid or Al- 
 kali therein*, by changing the Water red, if 
 an Acid, and green, if an Alkali prefjdes. 
 
 38. 0/7 difcovers any fmall Propor- 
 
 tion of earthy Matter, lefs capable of diiTolving 
 in Water than that Salt*, by precipitating fuch 
 earthy Matter, in Form of a white Cloud, to 
 the Bottom of the containing Glafs, where it 
 colledls, and appears like a fubtile white Powder. 
 
 39. I'hefe Particulars may be fhewn, and 
 proved fatisfadorily, by adding to pure Water 
 a little of a known Acid, Alkali, diffolved Iron, 
 and fubtile Earth, or fine light Sediment of aii 
 earthy Water, and then applying the Syrup of 
 Violets, Galls, and Oil of 'Partar refpedively. 
 
 40. Suppofe, therefore, any unexperienced 
 Water to be examined; hrfc, drop into it a little 
 Syrup of Violets, and if this does not alter its 
 Colour, but keeps its full natural Bluenefs, the 
 Water is neither Acid nor Alkaline. If Galls 
 do not turn the Water black, it is not Irony, 
 nor Vitriolic *, and if Oil of Tartar does not preci- 
 pitate a white Powder, the Water holds no confi- 
 iiderable Proportion of earthy Matter. 
 
 41. The prefent Set of Experiments is capa- 
 ble of great Enlargement, by Means of many 
 other Additions, fitted to produce a Change of 
 Colour, or a Precipitation in Waters, according 
 
 as 
 
of Water. 89 
 
 .they are impregnated with Matters of certain 
 Kinds. Thus a Solution of Silver, by caufing a 
 Thicknefs or light Precipitation, difcovers a mi- 
 nute Proportion of Sea-Salt contain’d in Waters. 
 
 And there is fcarce a Salt, an Earth, or a Mine- 
 ral, hitherto known, but the Induftry of the 
 Chemift has found Means of difcovering, if it be 
 contained in any common or Mineral Water ; 
 efpecially, if to this we add the Ufe of Evapora- 
 tion, or the Way of bringing the folid Contents of 
 fuch Waters to a dry Eorm. So that if this 
 whole Affair were to be properly conducled, wt 
 apprehend it might in a fhort Time terminate 
 in a certain Difcovery of the Contents of ail the 
 Mineral Waters of the Kingdom *, to the great 
 Advantage of ordinary Life, and a confiderable 
 Improvement in the Art of Medicine, and many 
 other mechanical Arts and Trades, depending 
 upon the proper Choice and Ufe of Waters. 
 
 Exp E R I MENT VIII. 
 
 ^hat Mineral Waters are imitable by Art. 
 
 42. We took a Quart of the lighted and pu- Pyrmont 
 red Water we could procure, and added to 
 about thirty Drops of a drong Solution of Iron 
 made with Spirit of Salt, a Dram or more of 
 Oleum ^artari per deliquium^ and twenty, thirty, 
 or forty Drops of Spirit of Vitriol ; biit fo as 
 that the Alkali of the Oil of Tartar might pre- 
 vail : we now diook all brifkly together, and pou- 
 red out a Glafs for, tading; upon which, it was 
 found very remarkably to rcfemble Pyrmont- 
 Water. 
 
 • 43. This Experiment, tho’ but particular, 
 may afford us a general Rule for imitating any 
 Mineral Water propofed. The Rule is, by a 
 proper Analyfis to find the Contents of fuch a 
 ‘ ‘ Water, 
 
90 
 
 Purging 
 
 Waters 
 
 imitated. 
 
 Lecture the Fifth. 
 
 Water, and their Proportions, by Evapora- 
 tion, the Addition of tinging Ingredients, Qc, as 
 above mentioned a) *, then, by Means of fyntheti- 
 cal Chemiftry to compofe a fimilar Mixture. 
 Thus, for Example, we learn, by a proper Ana- 
 lyfis, that the Ingredients or different conftituent 
 Parts of Water rj, are a fubtile aqueous 
 
 Fluid, a volatile Iron, and a predominating 
 Alkali; adjoined together into one brifk, pun- 
 gent, fpirituous Water : And upon this Analyfis 
 our preceding Imitation was founded, by means 
 whereof, if the Proportions bejuftly hit, the arti- 
 ficial Fyrmont-^ 2XZX will greatly refemblc the na- 
 tural, and produce fimilar Effeds in the Body ; as 
 has been found upon Experience d), 
 
 44. The Imitation of this fpirituous Kind of 
 chalybeate Water is by much the moft difficult; 
 and may perhaps be rendered more perfe6l, if, in- 
 iliead of ufing the Solution of Iron in Spirit of 
 Salt, the pureft common Water be boiled in a 
 clofe Veffel, wdth a fmall Proportion of Okre, 
 foft Iron Ore, or Pyrites; the reft of the Pro- 
 cefs being conducted as above fet down. 
 
 45. The Imitation of the common purgative 
 
 Mineral Waters is facile: Thus Water is 
 
 imitated by barely difiblving three or four Drams 
 of Epfom Salt in a Quart of pure Water, made 
 fomewhat brifk or quick with a few Drops of 
 Spirit of Vitriol and Oil of Tartar deliauium, 
 fo as to let the Alkali prevail. And the fame is 
 to be underftood of any other Water, the 
 Contents of which are exactly known. 
 
 a) Sea Exp. YU, §. 35, 36, 37, &c. 
 
 b ) See hereafter the Lediure on Synthetical Chemlflry. 
 
 c) See above E.xp. VII. 
 
 d) See New Experiments and Obfervations upon Mineral 
 Waters. 
 
 46. And 
 
of Water. ' 91 
 
 46. And by a little farther Experience and Expe» 
 Application, we apprehend that thefe Imita-^^^^ 
 tions might be brought to a great Degree of 
 perfedion ; fo as to render the Trouble and 
 Charge of importing foreign Waters, or going to 
 drink them abroad, in a Manner unneccfiary. 
 
 But the Imitation of the alterative Waters, 
 fuch as thofe of Bath., Buckjlon^ Holt., has 
 hitherto fcarce been attempted ; nor can be ra- 
 tionally, for Want of their refpedive juft Ana- 
 lyfes, upon which fuch Imitations fhould always 
 be grounded. 
 
 Axioms and Canons. 
 
 1. We have feen, (i.) that Water is natu- 
 rally contained in fome of the dryeft and har- 
 deft Bodies, and in the dryeft A.ir ; (2.) that it- 
 felf naturally contains Air, and an earthy Sub- 
 ft'ance*, (3.; that it is the proper Menftruum of 
 Saits, dilfolving more of one and lefs of another ; 
 
 (4.) that one good Sign of its Purity and 
 W'holefomenefs is its Levity ; (5 J that the In- 
 gredients of a mineral Water may be difcovered 
 by chemical Experiments •, and (6.) that mine- 
 ral Waters are imitable by Art, guided by fuch 
 Difcovery a ), 
 
 2. That Water is of infinite Ufe in all the 
 Works both ot Nature and Art, as without it 
 there could be no Generation, Nutrition, or 
 Accretion performed in all the animal, vegeta- 
 ble, mineral, marine and atmofphericai Regions. 
 
 The Blood could not flow in the Veins, nor the Sap 
 in the Veftels of Vegetables, nor the Particles of 
 Minerals concrete and grow together, without 
 Vfater. It is this that makes the iargeft Part of 
 
 <5) See the LeBure 
 
 our 
 
92 
 
 Lecture the Fifth. 
 
 our Blood, our Drink, and our Aliment. 
 Without it there could be no Corruption, Fer- 
 mentation, or DilTolution carried on a) \ no 
 Brewing, no Diftilling, no Wines, no Vinegars, 
 no Spirits h), 
 
 3. That we meet with Water under an infi- 
 nite Variety of Forms, and in an infinite Va- 
 riety of Bodies ; as of Air, Vapour, Clouds, 
 Snow, Hail, Ice, Sap, Wines, Blood, Flefh, 
 Bone, Horn, Stones ^c. through all which it 
 feems to pafs unaltered, as an Agent or Inflru- 
 ment that fufFers no Alteration by Re-adlion, 
 but remains capable of refuming the Form of 
 Water again upon Occafion c). In which refpe6t 
 it greatly rcfembles that other Proteus Quickfil- 
 ver, which wemeet within the Form of Fumes, 
 Clouds, Sublimate, Precipitate, ^c. from which 
 it may be reduced to running Mercury again d). 
 
 4. That Water, in its common State, ap- 
 pears to be a Combination of all the Elements 
 together, as containing a Quantity of Fire, 
 which keeps it fluid, a Quantity of Air, and a 
 Quantity of Earth e), Wdience it can be no 
 Wonder that Water alone, as it appears to the 
 Senfes, fhould fuffice for Vegetation, in fome 
 Cafes where little Earth is wanted *, or for fup- 
 porting animal and mineral Life, where no great 
 Degree of Nutriment is required. And hence it 
 proves a Gluten or Cement to fome Bodies, and 
 a Solvent to others. Thus it confolidates Brick, 
 Plaifter of Paris ^ Stone, Bone, Cfc. but difTolves 
 Salts, and fubtile Earths approaching to Salts, 
 and becomes the inffrumental Caufe of their 
 Adion f). 
 
 d) See Le^. I. b) See the whole Work fajjim, 
 
 r) See Exp. I. See alfo LeEi. I IT. 
 
 d) See Mr, Boyle palTim. e) See Led, I. II. III. IW 
 f) See Led. I. the preceding Ledure pafiini ; and again, the 
 Ledure upon Fermentation, 
 
 That 
 
of IVater. 93 
 
 That Water conveys Nourifliment, or a 
 more fixed and folid Matter, to the Parts of 
 Vegetables, where that being depofited the finer 
 Fluid perfpires into the Atmofphere a ) i which 
 gives us the phyfical Caufe of the Dampnefs and 
 Unwholefomenefs of woody Countries, which 
 they remarkably find in America, For^ all large 
 Vegetables a6t after the Manner of Pumps, 
 continually drawing in large Quantities of Wa- 
 ter at their Roots, and difcharging it at their 
 Leaves ; which intimates a Method of colleding 
 Water in dry Countries, and alfo of making 
 Salt-Water frefii. 
 
 6. That the Water in pafiing thro’ Plants, 
 after having depofited its more terreftrial Part, 
 does not always go off pure, but impregnated 
 with the finer Effluvia, or more fubtile Particles 
 of the Vegetable; thus making an Atmofphere 
 round every Plant, odoriferous or otherwife ac- 
 cording to its Nature: which fupplies us with a 
 Rule for procuring the odoriferous Waters of 
 Vegetables by Diftillation b), 
 
 7. That the Particles, which are not fine 
 enough to go off thus along with the Water, 
 are left behind upon the Surface of the Leaves 
 and Flowers of Plants; being now thickened 
 or ffrained from their moifter Parts, and remain- 
 ing in the Form of Honey, Manna, Gums, Bal- 
 fams, according to the Nature of the Vege- 
 table c). And hence appears the phyfical Caufe 
 of Plants proving more odoriferous and fweet, 
 when the Weather is both warm and moift ; as 
 immediately after a Summer’s Shower. 
 
 8. That the chemical Operator fhould form 
 to himfelf an Hygrometer d)y for the Service of his 
 
 ; See Exp. HI. ^c. h) See Exp, III. 1 2. d’c. 
 
 See Exp. ill. 
 
 ^7 As of Sponge, Salt of Tartar, Oil of Vitriol, Oit-beards, 
 
 ^ c, which attract the Moiilure of the Air. 
 
 Labo- 
 
94 - 
 
 Lecture THE Fifth. 
 
 Laboratory, to determine the Proportion of 
 Water at all Times contained in the Air ; which 
 continually mixes with his Preparations, diffe- 
 rently 'augments their Weight, and promotes or 
 hinders many ot his Operations a)^ as we find 
 , particularly in making the Oleum Sulphuris per 
 Campanam, zndi Oleum Tartari per deliquium^ both 
 of which fucceed beft in a moift Air. 
 
 9. That pure Water makes the largefb Part of 
 mineral Waters, where it is impregnated as a 
 Menftruum with feveral Ingredients, which it 
 diffolves or takes up in its Paffage thro’ the 
 Earth c\ 
 
 10. Lajlly^ The preceding Enquiry affords ' 
 confiderable Light for difcovering pra6licablc 
 Ways of making Sea- Water frefh and potable ; 
 and of preparing Waters by Art, fo as to ren- 
 der them fitter for the common oeconomical Ufes, 
 and the Service of many particular Arts ; as Me- 
 dicine, Pharmacy, Chemiftry, Brewing, Diftil- 
 ling, ^c. d) 
 
 a ) See Exp. II, See alfo LeSi. Ill, 
 
 b) SzcExp. VII. VIII. 
 
 c ) See 7, 12, 14, & Ax. 5, ^ c. 
 
 d) See §. 40. 
 
 L E C- 
 
[ 95 ] 
 
 LECTURE VI. 
 
 CONTAINING 
 
 An Enquiry into the Nature and Ufe of 
 Menjlruums^ or Solvents. 
 
 i.TWTE have now gone thro’ the common Introduc- 
 V V Elements, Fire, Air, Earth, and^^'®«* 
 Water : we next proceed to Menfiruums^ which 
 make a large Branch of Natural Philofophy, and 
 a more peculiar and immediate PartofChemiftry. 
 
 2. By Menjlruums we underfband all thofe Bo- Menfru- 
 dies, which, in a fluid, or fubtilized State, are«wiwW. 
 capable of interpofing their fmall Parts betwixt 
 
 the fmall Parts of other Bodies, fo as to divide 
 them fubtilely, and form a new uniform Com-- 
 pound of the two. 
 
 3. Hence folid Bodies, as well as Fluids, 2x0 Solid and 
 capable of becoming Menflruums, when their 
 
 Parts are fubtilely divided, fo as to receive others 
 uniformly between them-, whether this fubtile 
 Divifion and joint Interpofition of Parts be ef- 
 fedted by Fnfion, Triture, or the like. 
 
 4. Thus when two Metals, being fufed x.ogt- 7he Def- 
 ther, mutually interpofe their fubtile Parts be- 
 tween each other, and unite into one uniform 
 Mafs, they become Menftruums to each other. 
 
 And fo when common Sulphur and common 
 Mercury are barely rubbed together, till the 
 Mafs becomes every Way uniform and fimilar, 
 the'Sulphur proves a Menftruum to the Mercury, 
 and the Mercury a Menilruum to the Sulphur; 
 
96 
 
 ^he Men- 
 Jiruums Oj 
 Nature, 
 
 The Pur- 
 port of the 
 Ejcperi- 
 ments. 
 
 Lecture the Sxith. 
 
 and both uniting form that black uniform Powder 
 called jfEthiops Miner alis, 
 
 5. Whence it appears, that the Term Men- 
 ftruuni is equally applicable to both the Todies 
 concerned ; the one being as much a Menftruum 
 as the other. So when Water diflblves Sugar, it 
 mayas judly be faid that the Sugar diflblves the 
 Watery tho’ Cuftom, and the common Forms 
 of Speech, which have little Regard to juft and 
 philofophical Notions, do not authorize the 
 ExprefTion. 
 
 ; 6. And hence it may appear that the common 
 
 ' Elements, which we have confidered in the fore- 
 going Ledures, are in a proper Senfe the Men- 
 Jiruums of Nature^ which fhe eroploys for pro- 
 ducing her ordinary Effects. For Fire mixes uni- 
 formly among Bodies, and divides their Parts ; 
 fo does Air, Water, and elementary Earth, as 
 we have all along Ihewn. We fuppofe it will 
 not therefore appear foreign, but direflly con- 
 ducive to our Purpofe, to have beftowed a Lec- 
 ture upon each of thefe Elements, by way of 
 Foundation for our Courfe ; as thefe are not 
 only the principal Agents of Nature, but are alfo 
 concerned in every chemical Operation. 
 
 7. The prefent Bufmefs will be to fhew, (i.) 
 the different diffolving Powers of Water, on dif 
 ferent Bodies. (2.) The fame of Alcohol. (3.) 
 The fame of Oil. (4.) The fame of unlikely 
 Subftances. (5.) The fame of Quickfilver. (6.) 
 The fame of the common Menflruums, Aqua 
 Fortis and Aqua Regia, And (7.) the fame of 
 the Digeftor : thus proceeding gradually from 
 the weakeft up to the ftrongeft diffolving Powers 
 hitherto known in Chemiftry. 
 
 Exper^x 
 
Of Menfruums. 
 
 Experiment 1. 
 
 ^hat Water ^ as a Menftruum, dijjolves more of 
 one Body^ and lefs of anoiher, 
 
 8 . We took three fimilar and equal GiafPes differ 
 each containing two Ounces of the fame Kuid 
 
 of Water, cold ; into the firff we pur a certain 
 weighed Qjanrity of Epjom S ilt, viz two Ounces, ^ 
 the greatclt Part whereot was loon diilo-v'ed *, iiitoitruum. 
 the fecond we put a certain weighed Quintity’ 
 of dry and pulverized common Salt, ViZ, five 
 Drachmis, which likewife loon difiolved almofb 
 entirely ; into the third we put a certain weighed 
 Quantity, viz. eight Grains, of finely pulverized 
 Cream of Tartar^ whereof fcarce any l^art appea- 
 red to difibive in the cold. We fet all the GlafiTes 
 in Balneo Maria^ till the Water of the Balneum 
 boiled, and then obferved that more of each Sait 
 was taken up refpedfively. 
 
 9. It might be proper, for the further 
 provement of Chemiftry and Natural Philofophy, 
 to form a Table of the Time and Quantity 
 wherein all the known Salts are difiblvable in 
 Water. Epfom Salt, we fee, preiently difiblves 
 in about an equal Qjantity of Water *, common 
 Salt difiblves in about four times*, Nitre in a- 
 bout five or fix t mes; and Salt of Tartar in a- 
 bouf twice its own Qjantity of Water : but Cream 
 of Tartar recjuires twenty times its own Q^.iantity 
 of boiling Water to difibive it. 
 
 10. Such a Table, ^ regularly formed, m’ght 
 eafe the Trouble of refining Salts, by fhewing 
 at once, without future Trial or Lofs of Time, 
 how much Water each ^alt required to difibive 
 it, for Clarification, Filtration, or Cryfiallization. 
 
 11. It w'ould likewife lupply us with a ready 
 and commodious Way of feparating any Mixture 
 
 H of 
 
9? 
 
 Accounted 
 
 for. 
 
 Lecture the Sixth. 
 
 of Saks, by fhewing which would firft (hoot out 
 of the Mixture upon Cryffallization. For the 
 Rule is, that the Salt which requires the largeji 
 Proportion of Water to dijfolve it will jlooot the 
 firfi. And thus Nitre,, requiring a larger Pro- 
 portion of Water to d.flblve it than common 
 Salt docs, the former is, in the ordinary way of 
 refining, totally feparated from the latter by Cry- 
 ftallization. And unlefs this were to happen, the 
 Aqua- For tis prepared from Nitre would prove 
 a kind of Aqua-Regia^ and, inftead of diflblving 
 Silver, would diffolve Gold ; For Aqua- Regia is 
 made from a Mixture of Nitre and Sea-Salt, or 
 Sal Ammoniac, which contains the Spirit of Sea- 
 Salt ^ . 
 
 12. The fame Table might alfo dire6l us to 
 a ready and commodious Method of feparating 
 two Salts, without waiting for Cryftailization. 
 Thus fuppofe Tartar of Vitriol mixed with Epfom 
 Salt, if Water be poured upon the Mixture, it 
 will prefently diflblve the Epfom Salt, leaving the 
 Tartar of Vitriol untouched, fo that it may be decanted 
 clear from it •, becaufe Tlpfom Salt eafily and plen- 
 tifully diflblves in cold Water, whereas Tartar 
 of Vitriol diflblves flowly and fparingly in it. And 
 the fame is to be underftood of ocher Mixtures 
 of Salts. 
 
 13. If the phyfical Reafon be demanded, why 
 one Salt diflblves more readily in Water than ano- 
 ther, we recommend it to farther Examination 
 whether all Salts do not diflblve in Water with 
 greater or lefs Facility, and in greater or lefTs 
 Proportion, according as they contain more or 
 Icfs of a grofs, unduous Subftance, unfuitable 
 to the Nature, or to theFinenefs and Lubricity of 
 Parts required in Water. The comparing of 
 
 * See hereafter Exp. VI. 
 
 Epfom 
 
Of Menjiruums. gg 
 
 Epfom Salt, Salt of Tartar, common Salt, 
 with Nitre, Alum, crude Tartar, feem to 
 make this more than a Conjedure. 
 
 14. Vitriols alfo, being a Species of Salts, thence 
 become foluble in Water. But pure Water has ' 
 not the Power of difiblving Metals, unlefs they 
 are firft reduced to a Saline or Vitriolic Form i 
 Nor does Water ad as a Menftruum upon Oils, 
 
 Rofins, Amber, Sulphur, Whence its Power, 
 as a dired Solvent, is limited For Salts it 
 feems the appropriated Menftruum \ but, with 
 the Affiftance of other things, it may dilTolve a 
 great Number of other Bodies : Thus, by the In- 
 terpofition of Wax, it will difTolve Oil by fimple 
 Triture ; by means of the Yolk of an Egg it will 
 dlBblve Turpentine ; and by means of acid Spirits 
 
 it will difiblve Chalk, Earths, and Metals. 
 
 15. In our prdent Experiment v/e find thedif- 
 folving Power of Water increafe with Heat *, and 
 this holds till the Water boils : after which, as 
 the Heat remains the fame, fo does the difiblving 
 Power, and as this Heat decreafes, To does that 
 Power, letting Part of the Salt fall down again. 
 Whence it fhould feem as if Pleat was the original 
 Cauie of the dilTolving Power. 
 
 16. But on the other Hand, there are Experi- 
 
 ments wherein the Power of Water, as a Men- 
 flruum^ decreafes, as the Degree of Heat inCreafes; 
 as in boiling the White of an Egg-, where the 
 V/ater, as it grows hot, coagulates the Subjed: 
 which it would difiblve when cold. We alfo ob- 
 ferve the fame of Blood, a firm Mixture of 
 Flower and Water, The Inffances of this 
 
 Kind fhould therefore be collcded, and go along 
 with the former, to prevent the Mind from runn- 
 
 * SsQl^ct. V. §. 17, 18, &c. 
 
 Pi 2 ing 
 
lOO 
 
 Lecture the Sixth. 
 
 ing into Error, by concluding hadily from too 
 few Experiments, which has greatly prejudiced 
 Chemidry and Natural Philofophy. 
 
 Experiment II. 
 
 dijjolving Po'iver of Alcohol. 
 
 Alcohol 
 
 nvhat. 
 
 Camphtre We took an Ounce of Alcohol^ and by de- 
 
 dipl^ed grees added to it an Ounce of folid Cam ph ire ; 
 inSpiritof which it nearly difibivcd, in a very (hort Time, 
 without any Ebullition, or apparent Alteration 
 of Fluidity or Tranlparency. We afterwards 
 poured in a large Proportion of fair Water, which 
 weakening the Solution, and uniting with the 
 Alcohof c'aufed it to let go the Camphire *, fo that 
 now it all rofe, white, folid, and perfecfl, to the 
 Top of the Mixture. 
 
 1 8. Alcohol, or highly rediEed Spirit of Wine, 
 is a Liquor obtained from vegetable Subjeds, by 
 Fermentation, Diftillation, and Rediification af 
 It appears related to Oil, becaufe totally inflam- 
 mable ; and when carefully examined, to* be the 
 eflential Oil of the Vegetable, intimately broke, 
 and ground in among the Particles of Water ^ 
 fo as to form one uniform Liquor, not eafily fe- 
 parable again into different Parts Z>). 
 
 19. We learn, by the prefent Experiment, 
 that it has the Power of diffolving about its own 
 Weight of Camphire *, which when duly exami- 
 ned, appears to be a particular Kind of volatile, 
 or eflential Oil, coagulated into a white and folid 
 Subflance^) : And, as fuch an Oil, it is here plen- 
 tifully diflToIved in Alcohol. 
 
 ItsUfes. 20. This Alcohol is a capital Menftruum in 
 Chemiftry, and fitted to diflblve Roflns, as well 
 
 n) See the LeSlure upon DifiiUatlon hereafter. 
 h) See hereafter XV 1. Exp. lU. 
 
 as 
 
1 01 
 
 Of Menjiruums. 
 
 as Oils; tho* it does not thus mix inextricably 
 with either, but leaves them leparable again by 
 I the bare Addition of Water, which it dilTolves 
 more readily than either Oil or Rofin, and 
 ‘ therefore lets them go to join with this, accord- 
 ing to the Law of Precipitation. For whenever 
 P cne Body has dijjolved another^ if a third he ad- 
 I' ded to the Solution^ which third has a greater Re- 
 lation to either of the former^ than they have to each 
 other ^ their Union is feparated^ and the third Body 
 dijjolved injiead of the Jirji or fecond *, one of which 
 is now at Liberty to rife^ or fall to the Bottom^ ac- 
 cording to its fpecijic Gravity : as we faw remark- 
 ably in the prefent Experiment, where the Cam- 
 phire, didbivcd in the Spirit of Wine, was foon 
 made to float upon the Surface, by the Addition 
 of Water, which has a greater Appetite of Union, 
 or Relation, to Spirit of Wine, than that Spine 
 has to Camphire. And the phyfical Reafon hereof 
 may appear from what was jufl: now faid of the 
 Compofition of this Spirit, or its being an inti- 
 mate Mixtiu*e of Water and volatile Oil 
 
 21. Hence Alcohol is an intermediate Sub- 
 ftance betv/ixt Oil and Water, and related to 
 both, tho’ participating more of Water than of 
 Oil : And according to thefe Relations, its Ac- 
 tion as a Menftruum may, we conceive, be pro- 
 perly explained. 
 
 2 2 . By means of this Menjiruum the Tindlures 
 of Myrrh^ Gum Lac^ Guataam^ mod of the 
 Varnifhes, and many medicinal Tinctures, Eli- 
 xirs, and Solutions are prepared ; tho’ for thefe 
 Purpofes it ufually requires to be acuaied with 
 Salt of Tartar. But our prefent Buflnefs is to con- 
 flder the Power of Ample Menjiruums^ rather than 
 of fuch as are mixed ; for that were an infinite 
 Field, and would lead us too far for the prdtnt, 
 * See 1 8. 
 
 ' H3 
 
 Tho’ 
 
102 
 
 OiUif 
 
 Johjes 
 
 Lead, 
 
 The Expe 
 yiment ex 
 Uitdsd. 
 
 Lecture the Sixth, 
 
 Tho’ the Difcovery of powerful, yet innocenc 
 Menftruums^ by means of Compofition, fhould be 
 earneftly recommended to the Diligence of every 
 Chemift, as that on which the Improvement of 
 numerous Arts depends. 
 
 ExPER-IMENT III. 
 
 T^hat Oil 'imll intimately dijfolve Lead, 
 
 23. We put two Ounces of crude Lead into ah 
 Iron Ladle, and added thereto twelve Ounces of 
 Oil-Olive ; then fetting them over a clear Fire, the 
 Lead evidently meked before the Oil began to 
 boil, and at length the Lead difappeared, or 
 united and became one with the Oil. By flop- 
 ping the Operation at any time, we could eafily 
 learn how much of the Lead was dilTolved in 
 the Oil, both by the increafed Confidence of the 
 Oil, and the Diminution of the Lead. 
 
 24.. The fame Experiment may hold alfo of 
 * Tin, and of Tin and Lead mixed. How far 
 it is applicable to the other Metals has not been 
 hitherto fatisfadorily tried. Some have fuppofed 
 that Oil will difTolve Copper and Iron : But it 
 fhould be carefully exami’ned whether the efFe6b 
 be not owing to an Acid concealed in the Oil ; 
 for it is the known Property of Acids to difTolve 
 thefe Metals. This has been obferved, that if 
 Oil be well boiled, to get out its aqueous Parts, 
 it is the better fitted to preftrve U.enfils of Iron, 
 Brafs, or Copper, from Rufl:. Whence Marrow 
 is reckoned better for this Purpofe, than other 
 Fats or Oils more fubjedl to harbour aqueous 
 Moiflure. And if a little Cerufe, or Black Lead, 
 be added in the boiling, the Oil becomes flili 
 more proper for this Purpofe. Now it is the Pro- 
 perty of Cerufe, and black Lead, to drink up 
 Acids j and therefore it may be hence concluded, 
 
 that 
 
Of Menjlruurns. 
 
 that fome acid Parts, naturally contained in Oils, 
 arc the Cauie of their Rafting or Diflolving the 
 Iron, Brals, or Copper, on which fuch Oils are 
 
 25. The Preparation, or Subftance, obtained //^ xjfeu 
 in the prefenc Experiment, being taken from the 
 
 Fire at different times of the Operation, makes 
 either a Balfam, a Cement, or a Plaifter ; and fo is 
 fit for various U^es. As a Balfam,and a Plaifter, 
 it is ferviceable in Chirurgery. As a Cement, 
 it is excellent in Water-Pipes*, and being laid 
 upon hot Brick-work, or the like, fits it for 
 holding Water. It alfo ferves to hold crack’d 
 Glaffcs together, fo that they fhall be as firm ia 
 the Crack, as in the Sound Parts. 
 
 26. But a more phyfical Ufe of the Experi- 
 ment is, to fhew the great Affinity which the fofc 
 and fluid Body of Oib, as a Menftruum^ has with 
 the folid Bodies of Metals, and how they may 
 mutually, not only diffolve, but dilguife and con- 
 ceal each other ; fo that Metals fhall be contained 
 in Bodies where the Eye would never fufped: 
 them. 
 
 27. The prefent Experiment alfo affords fome 
 Light .in the Dodtrine of Solders, or, the Mix- 
 tures of metalline Matters, that will run with a 
 kfs Degree of Heat than the Metal propoled to 
 be folder’d, and tenacioufly lay hold thereof. 
 
 For Oil, or Greafe, is an ufeful Thing to facili- 
 tate the running of thefe Solders ; as we fee in 
 the Soldering of Lead and Tin, where the Plum- 
 ber ufes his Tallow, as the Tinman does his 
 Rofin ; by means whereof the Solder and the Me- 
 tal are the better foften’d, and in fome Meafurc 
 diflblved and incorporated together. TheReU- 
 
 28. We defire that this great Affinity be- 
 twixt Oils and Metals may be remember’d ; 
 
 laid. 
 
 H4 
 
 being Mefa/s. 
 
iOA 
 
 T V* 
 
 X JLi 
 
 Thread 
 
 dijiilkd. 
 
 Tlfes of the 
 Experi- 
 
 tiieai. 
 
 Lecture 
 
 E Sixth. 
 
 being of extenfive Confequence in the Bufinefs of 
 Metals, and more particularly in the lublimer 
 Metallurgy •, where catain Exprefiions, concerning 
 the SullJjur of Metals may be underftood to ad- 
 vantage, by t.king them to mean an adually in- 
 flammabie Subltance, or Oil. 
 
 Experiment IV. 
 
 ^hat innocent and unlikely SuhjeEls may afford pow~ 
 erful Menftruums, Jhewn in Bread. 
 
 29. We rook two Pounds of common brown 
 Bread, cut it into fmall Pieces, and put it into a 
 Gtals Retort. We placed the Retort in a Sand- 
 Eleat, and luring on a Receiver, diftilled with 
 a moderate Fire, io long as any aqueous Liquor 
 came over : at length luffering all to coo), we 
 took off the Receiver, and by the Filtre feparated 
 the Liquor obtained, to clear it of its Oil. This 
 Liquor we redlincd fiom its Phlegm in Balneo 
 Maries^ and afterwards difHiied’ it over again 
 in a Sand- Heat, to as to obtain a moderately 
 ffrong, acid, limpid Fdquor, under the name of 
 the redified Spirit of Bread. 
 
 30 In this manner we obtain from common 
 Bread a large Proportion of an aqueous Liquor, 
 mixed with acid Parts, fo as to be capable of ex- 
 trading the red Colour out of Coral, or even 
 Garnets. But to procure this Liquor in its greatefl 
 Strength and Perfedion, we fhould make Ufe of 
 Rye Bread, or fome of the coarier forts. 
 
 31. The Experiment being duly profecuted, 
 affords us the Analyfis of Biead *, a Subfiance 
 capable of recruiting and forming all the folid 
 Parts of our Bodies. And no wonder, fince ic 
 contains nv^^arly the fame Principles as animal 
 Matters. For Blood, Flefh, or Bone, upon their 
 Analyfis, refolve into Water, Oil, volatile Salt, 
 
Of Menfrumns. 105 
 
 and Earth •, the whole, by Dccoftion, making 
 a Kind of mucilaginoiis, or gelatinous Subftance 
 with Water: And in the fame manner Bread boils 
 with Water into a gelatinous or mucilaginous Sab- 
 ftance, and when diliilled. refolves into Water, 
 an acid Spirit, Oil, and Earth. The principal 
 Difference between them is, that Bread affords a 
 volatile A id by Diftillation, whereas Flefh, or 
 Blood, affords a volatile Alkali, Whence it fhould 
 feem, that there is in the Body a certain Power of 
 Changing the Matter of an Aitd into that of an 
 Alkali *. 
 
 32. To gain a clearer Information from Extended. 
 prelent Experiment, we could wifli it were repeated 
 
 with fuch Bread as contains no Sea-Salt, which 
 is a common ingredient in the ufual Kinds of 
 Bread. For Sea-Salt affords a confiderable Pro- 
 portion of acid Spirit upon Diftillation, and this 
 Spirit may have a great Share in diffolving the 
 Bodies fuppofed to be diffolved by the Spirit of 
 the Bread. But however that Matter may prove, 
 the Experiment ihews a pov/erful Menftrmm is 
 obtainable from an innocent and unlikely Sub- 
 jedt. And the fame has been found to hold of 
 many other Preparations ; as Wine-Vinegar, 
 tartarized Tartar, (Ac. Whence the like Experi- 
 ments fhould be tried upon other common Sub- 
 jeds , fuch as the Yolks and Whites of Eggs ; 
 
 Renner, Curd, Whey, Milk, Butter-Milk, Cheefe, 
 
 Urine, lAc. in order to difeover whether fervice- 
 able Menfiruums might not be thus procured, 
 
 EX'P E R I M E N T V. 
 
 ^hat ^dekfther dijjohes Metals, 
 
 33. We melted two Ounces of clean Lead in Amalga<^ 
 an Iron Ladle, and in another Ladle we heated mation of 
 
 * Sec more to this purpofe in LeSl. VII. 
 
 the 
 
io6 
 
 ^he Expe 
 r intent ex 
 tended, 
 •vjtth its 
 Vjes, 
 
 Lecture the Sixth. 
 
 the fame Quantity of Quickfilver till it juft 
 began to fume ; then we poured the Quickfilver 
 to the Lead, and ftirr'd them both together with 
 an Iron Rod : upon letting them cool, they made 
 a white, hardifh, homogeneous Mafs ; a part of 
 which, being ground with more frefh Quick- 
 filver, readily and intimately mixed therewith. 
 
 34. This Experiment fucceeds with ail the 
 - Metals, except Iron ; which therefore appears 
 
 of a lefs mercurial Nature than the reft. The 
 Operation itfelf is called Amalgamation^ that is, 
 the intimate Mixing of a Metal with Quickfilver, 
 and is the Foundation of Gilding and Silvering. 
 For an Amalgam of Gold being rubbed upon a 
 well polifhed Plate of pure Silver, and the Plate 
 afterwards expofed to fuch a Degree of Pleat as 
 will evaporate the Quickfilver of the Amalgam, 
 the Plate is left gilt. The Cafe is the fame 
 when Copper is to be filver’d. And thus Gold, 
 or Silver, is uniformly diffufed through the Body 
 of the Quickfilver *, whence a fingle Grain of 
 Gold, Silver, Lead, or Copper, may be divided 
 to an almoft inconceivable Degree ; or fpread 
 uniformly through a Mafs of a thoufand Pounds 
 Weight of Quickfilver, every the fmalleft Par- 
 ticle of which fliall contain a Quantity of Gold 
 proportionable to the Whole. And hence it 
 appears that Quickfilver is a true Menjiruum to 
 all the Metals, except Iron ; diifolving them as 
 perfedlly as Water diflblves Salt. 
 
 35. The prefent Experiment alfo fhews us 
 how Quickfilver may be adulterated with a Pro- 
 portion of Lead : but the Fraud is eafily difeo- 
 vered, by putting a little Quantity of fuch de- 
 bafed Quickfilver into an Iron Ladle, and exha- 
 ling away all the Mercury which will thus leave 
 the Lead behind. 
 
 36. Wc 
 
Of Menflruums. 107 
 
 36. We may likewife hence underftand the 
 fraudulent Tricks of fome pretended Aichemifts, 
 who feigning an Cccafion for the Ufe of Mer- 
 cury in their ProcelTcs, do beforehand fecretly 
 diffolve, or procure to be diffolved therein, a 
 certain Proportion of Gold or Silver \ which not 
 flying off along with the Qiiickfilver in the Fire, 
 the credulous By-flanders are made to believe, 
 that the bafer Metals employed are enriched 
 with the nobler in the Operation. The Inftan- 
 ces of fuch Frauds are many, and have brought 
 a great Stain upon the Art of Alchemy. But 
 they are eafily detected, by expofing a Part of 
 the Operator’s Mercury to the Fire ; for the 
 Quickfilver going off in fume will leave the 
 Silver and Gold behind. 
 
 Expe rime NT VI. 
 
 fhat Aqua-Fortis, cr Spirit of Nitre ^ is the Men- 
 ftruum for Silver \ and Aqua-Regia the Men- 
 ftruum/?r Gold. 
 
 37. We took two Drachms of the finefl: Silver Gold and 
 
 reduced to Filings, and poured upon it twice its Siherdif- 
 Weight Aqua-Fortis \ then let the con- 
 
 tainingGlafs in a gentle Heat, under a Chimney, 
 
 till the Solution was perfectly made. 
 
 38. We took ten Grains of Leaf-Gold, and 
 poured upon it two Drachms of Aqua- Regia ; 
 then let the Glafs in a Sand Heat to warm tho- 
 roughly. After the Gold was diffolved we ad- 
 ded a Grain or two more, till the Menjiruum 
 was fully faturated, and then decanted the clear 
 yellow Solution. We afterwards put a few Grains 
 of Silver into Aqua-Regia^ and a few Grains of 
 Gold into Aqua-Fortis ; and kept the containing 
 Glafs warm,' in the fame manner as before, but 
 found no Solution enfue in either cafe. 
 
 39. Thus 
 
io8 
 
 Prcof-A- 
 qu'i- Foitis 
 n^hat. 
 
 made. 
 
 Aqua-R£‘ 
 gia <vohat. 
 
 of the 
 Solution of 
 St her. 
 
 Lecture the Sixth. 
 
 39. Thus we fee that Gold and Silver are per- 
 fedly difToIved in their refpedive Menftruums^ 
 neither of which will touch the other Metal. For 
 if any Gold be contained in the Silver, it will 
 fail to the Bottom of the Solution in the form 
 of a black Powder; and if any S iver be con- 
 tained in the Gold, it does fo likewife. 
 
 40. The Jqua-Fortis^ for the Solution of SiF 
 ver fliould be made Proofs that is, it fhould be 
 capable of diaolving half a Grain, or a Grain of 
 Silver immediately, without growing in the lead 
 turbid •, as it would do if it contained any Sea-Salt : 
 in which Cafe it would be a Kind of Aqua-Regia, 
 
 41. Aqua Fertis is made by diftilling purified 
 Nitre with calcined Vitriol, or redified Oil of 
 Vitriol, in a ftrong fdeat, whereby an extremely 
 corrofive acid Liquor is driven over in blood-red 
 Fumes. 
 
 42. Aqua-Regia is made by difiblving a fourth- 
 part of Sea-Salt in the Aqua-Fortis above men- 
 tion’d. 
 
 43. If the Silver employed in the Solution were 
 abfoiutely pure, the Liquor will be pellucid : 
 but if any Alloy, or Copper, remain mixed with 
 it, the Solution will have a bluifh or greenifh 
 Cad. If a "'''olution of perfectly pure Silver be di- 
 luted with fair Water, it wfill dill remain pellu- 
 c'd, without letting any thing precipitate. But 
 if any faline Matter be contained in the Water, 
 the whole will now turn thick or milky. The 
 Solution of pure Silver, when properly weaken’d 
 with Water, may be commodioufiy ufed for 
 daining the Skin, or other animal Subdances,' 
 black. And if white, grey, or red Hair be 
 moidened with it, the Hair will foon become of 
 a beautiful brown, or jet-black Colour. For 
 which purpofe it may be ufed with Safety, Care 
 being taken not to touch the Skin therewith ; for 
 
Of Me 7 tfruums. 109 
 
 thus a Blacknefs would be occafioned, that re- 
 quires many Days before it goes off again ; but 
 it difappears at length, by the Scarf Skin peeling 
 off, without caufing any Pain, or leaving any 
 Sore behind. 
 
 44. The Solution of pure Silver has an intole- 
 rably bitter Tafte*, tho’ to the Eye it be not di-* 
 ftinguifhable from fair Water: In which w^e have 
 an eminent Inftance how Metals may lie concealed 
 from the Sight, or remain lodged in unfufpedted 
 Liquors, and thence be introduced invifibly into 
 other Subftances. Whence the greater Caution 
 fhoLild be ufed with all Pretenders to the Melio- 
 ration and Tranfmutation of Metals. 
 
 45. This Solution of Silver is the Foundation 
 of feveral medicinal and chemical Preparations ; 
 as the Vitriol of Silver^ the Lunar Cauftic^ the 
 Silver- Pill^ &c. 
 
 46. The Silver is recoverable from this Solu- Siher 
 tion, barely by fufpending a Copper-Plate therein : ho^ re- 
 For Copper being more eafily diffolved by Aqua- 
 
 Fortis than Silver, the Silver is thereby preci- 
 pitated to the bottom, in the form of a Powder, 
 which being waflied and melted comes into a me- 
 talline Lump again. And this is aifo to be un- 
 derffood of the Solution of Gold. 
 
 47. Blit, on the other hand the Solution ^^jjreioPthe 
 Gold is yellov/, or gold coloured, and tinges the Solution of 
 Skin purple, as the Solution of Silver ftains it 
 
 black. It may be further added, that if the So- 
 lution of Gold be precipitated with Salt of T artar, 
 and the Powder carefully dried, it makes the 
 Aurum fulminans^ fo called from the violent Ex- 
 plofion with which it goes off, wTen heated 
 beyond a certain Degree 
 
 ■* See hereafter the Lecture upon Pyrotechny. 
 
 E)i: P E R I- 
 
1 lO 
 
 Lecture the Sixth. 
 
 '^{he St fit c- 
 ture and 
 Ufe of the 
 Digefors 
 
 Ox^Bofie 
 
 fojtend. 
 
 Rationale 
 of the Ex- 
 periment. 
 
 Its Ufes. 
 
 Experiment VIT. 
 
 Ihe dijffolving Power of the Digeflor, an Injlru- 
 ment contrived at once to direct the AElion of 
 Water ^ Air^ and Heat^ in a high Degree^ upon 
 a Subject, 
 
 48. The Digeflor is a ftrong Veflel made of 
 Copper, or Iron, and fitted with a clofe Cover 
 aiid Screws, fo as to remain perfedly tight, 
 in a confiderable Degree of Heat; whilft Water, 
 common Air, and the Subjedl of the Operation 
 are contained within. 
 
 49. We took a Pound of frefli Ox Bone in a 
 Tingle Piece, with two Quarts of common Wa- 
 ter, and leaving a confiderable Space for the 
 Atmofpherical Air, we fcrewed them all up to- 
 gether in the Digeflor^ and applied a moderate 
 Degree of Heat to the Bottom thereof, for about 
 a quarter of an Hour, or till a Drop of cold 
 "Water, let fall upon the Cover, would evaporate 
 in avery few Seconds of Time: after whichletting 
 all cool, we opened the Veffel,and found the Bone 
 Toft and tender, fo as to be cut with a Knife, 
 the Water about it turned to a hard Jelly, and 
 a large Quantity of Fat in a folid Cake at the 
 Surface. 
 
 50. The Effedls of this Inflrument will not 
 appear furprizing, if the Forces that aFt within 
 it be duly confider’d. For, as we have formerly 
 fhewed the inftrumental Efficacy of Fire, Air, 
 and Water to be very great, even when feparate, 
 it is no wonder they ffiould adl extremely flrong 
 upon a Body in conjundlion f . 
 
 51. Hence the Digeflor feems, of all the In- 
 fcruments, or VefTels, hitherto invented, the moft 
 
 * See the five preceding 
 
 / pow- 
 
of Menflruums. 1 1 % 
 
 powerful for increafing the Adion of Men- 
 firuums. And if a fuitable Method could be dif- 
 cover’d for ftrengthening the Engine, fo as to 
 work fafely with a very'itrong Degree of Heat, 
 we might reafonably exped; to perform fome 
 very extraordinary Operations by its means, m 
 the way of Extraction, Decoction, Tindlure, So- 
 lution, and perhaps even Deflrudlion, or Tranf- 
 mutation a). 
 
 52. But a Courfe of Experiments and Le6tures 
 upon this Engine alone, would fcarce be fujfhicient' 
 to Ihew and explain its numerous Ufes and Ap- 
 plications for improving the -Dodtrine of Men- 
 firmms. And what Effedis the common Solvents, 
 as Alcohol^ Oils^ Aqua-Fortis^ Mercury^ and Me- 
 tals themlelves, might have, when afiifted by this 
 Engine, is not eafy to foretel ; and indeed it would 
 require much Induftry and Application to dif- 
 eover them. 
 
 Axioms and Canons. 
 
 I. We learn from the preceding Enquiry, that 
 Water is a Menjirmm which, of itfelf, diiTolves 
 little more than Salts h) ; but, being alTifled by 
 Acids, diffolves Earths, and even Metals them- 
 felves c). And hence might be drawn 2^ general 
 Rule of Pra5iice^ for making Water an almoft 
 univerfal Menftruum, Thus, by the Addition of 
 a fixed Alkaline Salt, it diffolves Oil into a Soap; 
 by the Addition of Alcohol^ it extradfs the refi- 
 nous Tindlures of Vegetables : and in this Man- 
 ner it might be proper to run through the dif- 
 ferent Subjedls of the vegetable, animal, and mi- 
 
 a) See Dr. Papins Treatife of this Inllrument. See a!fo 
 the Lord Bacon'*s Pnilofophical Works, paffiin* 
 b") Exp. I. See alfo Lei^. V. 
 c) Exp.l.Wl, 
 
 neral 
 
112 
 
 Lecture the Sixth. 
 
 ncral Kingdoms, and form Tables of the folutivc 
 Powers ot Water, fm)pie and compounded. 
 
 2. I'hat fuch Tables may be readily formed 
 of the diflblving Powers of all the known Men- 
 ftruumSy to fncw by Infpeclion, in what Time, 
 in what Proportion, and with what Degree of 
 Heat, ail Solvents perform their Adion ; which 
 being once reduced to a Certainty, would greatly 
 facilitate and improve the Practice of Chemiltry^^}. 
 
 3. That the Power of Alcohol^ as a Mcnfiruum^ 
 is chiefly limited to Kofins and Oils *, but, by 
 certain Additions, may be extended, as was faid 
 of Water, fo as to become an almoft univerfal Sol- 
 vent hj> Thus, by the Addition of Water, it be- 
 comes Brandy, or Spirit, which extrads many 
 Tiniflures that neither pure Water nor pure 
 Ah'ohol will feparately extradt. Whence we have 
 a good Inftrudion lor attempting a new Set of 
 Menftruums by Mixture, or the Compofition of 
 tv^o or three Ample Solvents. And if the requi- 
 fite Care and Skill were employed in this Matter, 
 many ufeiul Difcoveries might be juflly expeded 
 from it. Indeed, the mixing of two Menftruums 
 may fometimes deftroy the Virtue of both : thus 
 Spirit of Nitre and Ample Water will each of 
 them feparately diAblve the human Calculus^ but 
 when mixed they will not touch it. This In- 
 ftance however is only particular, and there are 
 a large Number producible on the contrary Ade ; 
 which may rationally recommend a farther Pro- 
 lecution of this Enquiry. 
 
 4. That Metals are foluble in Oils, and in add 
 Spirits, fo as not tobeeafily difeovered therein r). 
 Whence a Rule may be drawn for a prudent Suf- 
 penfion of the Judgment, and a rational Dif- 
 
 rt) Exp. T. Seealfo he £ l . V. 
 
 F) Exp.U. 
 
 c) Exp. 111. VI. 
 
 truft 
 
Of Menfruums. 113 
 
 tnifl: of the Senfes in chemical Operations : And 
 alfo, a Caution againfl; being impoied upon by 
 the vain Pretences of Alchemifts a), 
 
 5. 1 hat the Power of a Menliruum is not to 
 be judged of by its Innocency with regard to the 
 animal Body. The acid Spirit of Bread is inno- 
 cent and wholefome, yet capable of diffolving 
 Coral and Gems h). Pure Oil-Olive will diffolve 
 Lead and Tin. The White of an Egg, boiled 
 hard, and fulfer’d to run per deliquium^ dilTolves 
 the tough Body of Myrrh. The Inftances of 
 this Kind are extremely numerous. They well de- 
 ferve to be colledled and tabled, that the Mind may 
 be thereby cured of the Prejudice it has too readily 
 imbibed, as if Corrofives only were Solvents. 
 
 6. That the A6lion of Menfiruums depends 
 upon a certain Secret and reciprocal Relation be- 
 twixt the Solvent and Solvend, fcarce cognizable 
 by the diredt Senfes, nor hitherto well made out 
 by Inftances and Induction. Alkali and Acid, 
 Attra( 5 lion and Repulfion, Sympathy and Anti- 
 pathy, feem rather Words coined to exprefs the 
 Adion, than to aflign the phyfical Caufes there- 
 of. And hence the Action of new Menfiruums 
 cannot be determined, or rationally conjedurcd, 
 beforehand ; becaufe it depends upon a Caufe not 
 hitherto known. 
 
 7. That Menfiruums have not their full Adlion, 
 unlefs reduced to a tiuid or fubcile State c). Wa- 
 ter in the firm and folid Form of Ice does not a6t 
 on Salts ; but they foon begin to difTolve each 
 other upon Contad Metals do not ad on Me- 
 tals, in the Way of Solution, till they are fufed : 
 
 Nor does Sulphur difTolve Quickfilver, till they 
 are both reduced, either to a fluid or very fub- 
 
 a) See above, §. 26, 33 —36. 
 
 b) Exp. IV. 
 
 c) See the Ledure, fajUtm. 
 
 I 
 
 tile 
 
II4- Lecture THE Sixth. 
 
 tile State, by Triture, or by Melting, And this 
 appears to be the Cafe in all Indances. Whence, 
 in order to promote the Adion of Menfirmms^ 
 we are direded to reduce both the Solvent and 
 Solvend to minute Parts, or as near as poihble 
 to a fluid State, whether by Heat, Triture, Fu- 
 fion, orotherwife. A.nd hence appears the phy- 
 fical Caufe of the Angular Efficacy of Fire, Air, 
 V/ater, and Trituration in promoting the Adion 
 of Menjiruums a). 
 
 8. That Quickfilver is a true Solvent of Me- 
 tals, incorporating with them, as Water does whth 
 Salts b) *, by which Means one Metal may be rea- 
 dily united with another, in any Proportion, by 
 Ample Triture c). And hereby alfo many Ope- 
 rations in the fublimer Metallurgy are chiefly 
 performed d). 
 
 9. That acid Spirits are not, equally, proper 
 Menjiruums to all the Metals *, thus Spirit of Nitre, 
 tho’ it diflTolves the reft, will not difTolve Gold e). 
 So neither is Quickfilver itfelf a proper Men- 
 Jiruum to them all •, for it does not diflblve Iron/j. 
 And the true phyfical Reafon hereof feems not 
 hitherto fatisfadorily difeovered, tho’ numerous 
 Conjedures have been made about it 
 
 10. That all the Bodies in nature may become 
 Menjiruums to one another, each of them being, 
 by fome Means or other, capable of having their 
 fmall Parts uniformly interpofed betwixt the fmall 
 Parts of any of the reft. Thus even Metals may, 
 by Art, be made to dilTolve in Water •, as we 
 evidently fee from numerous Solutions ot Metals 
 
 ' a) See the five preceding I.eftures, pojfini. 
 
 h) Exp. J and See allb Uii. V. 
 
 0 See above, f 33, 34 
 
 d: See hereafter the I enures on Mineralogy and MetaU 
 lur^y. 
 
 i) ^e.cExp.Y]. 
 
 J) Exp. V. 
 
 in 
 
Of Menjlruums. ^ 
 
 in acid Spirits : thefe Spirits being no more than 
 Water charged with the [ine or more volatile Karts 
 of Salts. 
 
 11. That the Caufe of Solution commonly af- 
 figned, viz. the AdmifTion of the fine Particles of 
 one Body into the Pores of another, whofe Figure 
 is fitted for their Reception, is not jufl or ade- 
 quate, but hypothetical and ill-prefumed, fince v/e 
 find that fome Bodies will uniformly difTolve their 
 own Quantity of others * as Water does of 
 Epfom Salt, Alcohol of efTemial Oils, Mercury of 
 Metals, one Metal of another, , whereas the 
 Sum of the P’ores, or Vacuities, of every Body 
 muft be necefiarily fefs than the Body itfelf ; 
 and confequently thofe Pores cannot receive a 
 Quantity of Matter equal to the Body wherein 
 they exift : for this were to make the contained 
 Matter bigger than the Pores that contain it. 
 
 12. That the difTolving Power of Water may 
 be immenfely increafed by means of the Digeftor.^ 
 an Inftrument not hitherto introduced into Che- 
 miflry, tho’ probably applicable to the great Im- 
 provement of that Art ; as being a Contrivance, 
 which at once determines the Adtion of a Solvent 
 upon the Solvend, with all the Advantages of 
 Heat, Air, and Water, brifkly agitated and' con- 
 fined, under a State of ComprefTure, fo as to 
 make them ad like different Sets of Stampers 
 upon the Matter to be changed. For this Engine 
 at once employs all the four Agents required to 
 make the greateft Part of Mcnftruiims ad with 
 Advantage; viz. Fire, Air, Water, andTriture. 
 
 Whence there are fome folid Grounds of Hope, 
 that it may, under a proper Regulation, greatly 
 contribute to the Improvement of Chemifbry, Na- 
 tural Philofophy, and Arts. 
 
 » Exp. i.n.v. 
 
 I 2 
 
 13. Upon 
 
ii6 . Lecture THE Sixth. 
 
 13. Upon the whole it fhould feem, that many 
 defirable Improvements are derivable to Arts 
 from an Improvement in the Bufinefs of Men- 
 ftruums The Difcovery of that common Men- 
 ftruum^ Aqua-Fortis^ introduced the Art of AfTay- 
 ing, and the Scarlet Dye. That of Alcohol in- 
 troduced the Arts of Varnifhing and Japanning^ 
 numerous Pigments for Painters, Colours for 
 Dyers, Tan-Liquors for Tanners, the Staining 
 of Bone, Horn, Ivory, Marble, various Kinds of 
 Ink, Tin6lures, and Solutions, in Medicine, Che- 
 miftry, and other Arts, have all refulted from n 
 the Difcovery of Menftruums, Yet the Subjedf 
 feems almoft as new and rich as ever *, fo that nu- 
 merous other Difcoveries, of the fame Kind, would 
 not exhauft it. 
 
 * See the whole Enquiry, fajjim. 
 
[ ”7 ] 
 
 lecture VII. 
 
 CONTAINING 
 
 An Enquiry into the Nature.^ Office y and Ef- 
 feEls of Fermentation and Putrefadlionj 
 in the Vegetabky Animaly and Mineral 
 Kingdoms, 
 
 T H E Purport of this Ledlure is to enquire 
 
 into the Nature, Effeds, and Ufes of^v^f?. 
 "ermentation and Putrefadion, as they are the 
 latural Means of converting one Body into an- 
 )ther *, in order to acquire a farther Knowledge 
 n the Cbemijlry of NalurCy and thence derive 
 bme ferviceable Rules for the Improvement of 
 '^hilofophical Chemiftry. 
 
 2 But as the Subjedfs of Fermentation and 
 ^utrefadlion feem to have been imperfedily treated 
 )y Authors, and to lie buried, as it were, in Ob- 
 curity, we lhall endeavour to let fome Light in 
 !pon them by particular Experiments, and our 
 ^Explanations of them-, fo as to fhew the Steps of 
 Mature and Arty in conducting and regulating 
 hefe capital OperationSy for altering and changing 
 egetable, animal, and mineral Subjects in the 
 bree grand Regions of Nature, viz. the Earthy 
 )cean and Atmofphere. 
 
 3. That we may proceed the more clearly, we TheQrder, 
 lall bemn with Fermentation in vegetable Sub- 
 iCts, and trace it thro’ all its Stages •, till at 
 :ngth it terminates in Putrefa£Hony which reduces 
 egetable Subjects to an animal Nature. We 
 lall next confider the fimilar Procefs in animal 
 I 3 Subjects^ 
 
Ii8 Lecture the Seventh. 
 
 Subjeds ; and laftly^ examine whether any Thing 
 ot the fame Kind obtains among Minerals. 
 
 I- . I 
 
 To begin with vegetable Subjecls : 
 Experiment I. 
 
 ^he Nature and Ufes of vinous Fermentation ; or the II 
 Way of changing the natural Juices of Vegetables 
 into Wines. 
 
 Wine 4 . We took a Quarter of an hundred of whole, 
 We’/z'ow or unbruifed, Malaga Raifms, and put to them 
 Gallons of cold Spring- Water, in a wooden 
 Vefiel or Cafk, which we let loofely cover’d in a 
 warm Place, that the Contents might ferment for 
 fome Weeks. We found that the Water foaked 
 thro’ the Skins of the Raifms, dilTolved their in- 
 ternal fweet or faccharine Subftance, and became 
 impregnated therewith, as a Menjtruum \ that the 
 Liquor manifeftcd an internal Struggle and Com- 
 motion of its Particles, throwing up numerous 
 fmall Bubbles to the Surface, with a confiderable 
 hilTing Noife ; and that when the Fermentation 
 was finifhed, the Liquor was become an actual 
 nev/V'/ine, as appear’d by the Tafte, Smell and 
 Effeds, having depofited a large Quantity of 
 grofs, earthy Pediment, called Lees, at the Bot- 
 tom, different from the Huflcs, or Skins, and 
 Stones of the Raifms. 
 
 fhe Expe- 5- This Experiment i^ univerfal, or fhews the ; 
 rimentex- general Manner of making Wines, and all other 
 unded, fpirituous potable Liquors, or Drinks, by Fer- 
 mentation. For, v/ith a flight Change of Cir- 
 cumftances, it is applicable to the Brewing of 
 Beer from Malt •, Mead or Metheglin from Ho- 
 ney ^ Cyder and Ferry from Apples and Pears 
 
 refpec- 
 
Of Fermentation and PutrefaSHon. 1 1 9 
 
 refpeflively ; artificial, or made Wines, as they 
 are vulgarly called, from Cherries, Goofeberries, 
 Currants, Elder Berries, Blackberries, Plumbs, 
 Oranges, or other Fruit; alfo, from the Tap- 
 pings of certain Trees, as the Birch, the Maple, 
 the Sycamore, and more eminently from the 
 Juice of the Sugar Cane, Treacle, or common 
 Sugar and Water. For any ot thefe vegetable 
 Juices, being duly fermented, afford as real and 
 perfect Wine, according to their feveral Natures, 
 as the richefi: Grapes of the beft Wine-Countries. 
 
 6. To bring any of thefe Juices into a found ^p- 
 Wine, the Rule is to evaporate them, if they 
 
 are naturally too thin, till they become of equal ^ 
 Richnefs tvith the Juice of the Grape, in Wine- 
 Countries and in good Wine- Years. ITis may 
 commodioufly be done, by Means of the com- 
 mon Water-Poife *, which fhews the Strength 
 or Richnefs of Solutions to the Eye. And in ge- 
 neral, any vegetable Juice, or Solution, is ac- 
 counted fufficiently rich for making a ftrong 
 Wine, when it will fuppoic a new laid Egg on 
 its Surface. 
 
 7. The Wines made at prefect in England lie 
 
 under a Difrepute ; the Reafon whereof feems 
 chiefly owing, to the irlartihcial Manner 
 
 wherein they are ufually prepared, fecondly^ 
 to a certain Rumour fpread about them, as if 
 they were unwholefome, crude, indigeflible, too 
 lufcious, too tart or griping, and apt to occafion 
 the Plead ach, &c. 
 
 8. Thofe, who have never been in Wine Coun- 
 tries, nor othgrwife made themfelves acquainted 
 with the Nature and common Preparation of 
 
 1 4 
 
 * See Lect. V. Exp. VI. 
 
 Wines, 
 
I 20 
 
 Lecture the Seventh. 
 
 Wines proceed in their Judgment of them accord- 
 ing to Report, popular Notions, and the imme- 
 diate Information of the Senfes. Thus, for In- 
 fiance, Red-Port Wines, to pleafe the common 
 Palate, mud be bright, deep-colour’d, rough, 
 rich and racy, two or three Years old, and 
 when this or any other Notion comes once to be 
 edabl idled as the Criterion of Vv' ine, the Cooper 
 is thereby dire(5fed how to hit the general 1 ade, 
 and make a faleable Commodity. 
 
 Upon the fame Foundation Philofophical 
 Chemijlry indru6ls us to imitate the Wine-Cooper, 
 and from almod any fweet and tart vegetable 
 Juice, to make faleable Wines, even Sacks, 
 Mountains, Sherries, or Ports ; all of which by 
 the way, are ufually mixed Liquors, tho’ the 
 Bads of them all is the Juice of the Grape. 
 
 lo This Juice of t’ e Grape being cliemically 
 examin’d and confidered, proves to be no more 
 than a large Proportion of real Sugar difiblved in 
 Water, with the Addition only of a certain Fla- 
 vour in the Juice of the Grape, according to the 
 Nature of the Vine. Whence we lay it down 
 as an Axiom^ and the Refult of a careful En- 
 quiry, that a faccharine Subjtance is the Bafis of 
 Wines, For Sugar is not peculiar to the Sugar- 
 Cane, but obtainable alfo from Grapes *, and ac- 
 cordingly we often find large Grains thereof in 
 dried Raifins ; particularly in thofe of Malaga^ 
 that have lain for fometime, and fweated together, 
 by which Means they run into Candy, a faccharine 
 Efflorefcence, and adlual Grains of Sugar. So 
 again, it is cudomary in France to evaporate the 
 Juice of the Grape till it becomes coaguluble in 
 the Cold, and in this State to ufe it as a moid 
 Sugar, under the Name of Refine. And the fame 
 Thing is to be underdood as pracdicable in Malt, 
 
 or 
 
Of 'Fermentation and PutrefaSUon. I2i 
 or Wort, and the fweet Juices of all Vegetables 
 that aiiord a Wine by Fermentation 
 
 11. Hence therefore we may derive a Set of ^uks. 
 Rules, for boiling down, or otherwife procuring 
 
 the eiientiai Matter of Winrs in a fmall Bulk, 
 and preferving it found and ferviceable for many 
 Years, in order to the Making of all Kinds of 
 Wines, Vinegars, and Brandies, even in Coun- 
 tries where no Vines grow. And this Difeovery 
 alfo affords great Light into the true Nature and 
 Ules of vinous and acetous Fermentation, 
 
 12. To illuffrate and confirm this Difeovery Praaice, 
 by an Example, upon the Footing of the prefent 
 Experiment : Take two hundred Weight and a 
 
 half of double refined Sugar; put it into a Pipe, 
 or Wine Veffel of two Hogfheads *, fill the Vef- 
 fel within four Gallons of the Top with pure 
 Spring-Water *, fet in a warm Place, orWine- 
 Vauit; and three or four Pounds of frefh Ale- 
 Yeafl, or rather of new W^ine-Yeafl ; and the 
 Liquor in a few Months time will ferment into 
 a found, colourlcfs, and flavourlefs Wine, and 
 remain fufceptible of any Colour or Flavour at 
 Pleafure •, fo as with the Stain called Furnfol., to 
 be made of the true Claret-Colour; and with a 
 little effential vegetable Oil, of any particular 
 ' Flavour required. And this is'here deliver’d as an 
 Experiment that fucceeds to great Perfedlion ; 
 fo as to fhew a rational and practicable Method 
 of producing Wines in the Sugar Colonies, or eJfe- 
 where, that fliall rival thofe of France.^ Italy, or 
 Spain ; and if the Nature of Fermentation be well 
 underftood, the Procefs may be greatly fliortened 
 in point of Time, as well as improved in other 
 Refpedis. 
 
 13. And fo much for the Ufe of our prefent 
 Experiment, with regard to Trade, and Oeco- 
 
 * See an EfTay upon the Art of Breiving and DlJUllation. 
 
 See alfo hereafter, Lea. XI. pajjitn. nnmv . 
 
122 
 
 Philo- 
 
 sophy. 
 
 Lecture the Seventh. 
 
 nomy. Its philofophical Ufes are no lefs confi- 
 derable. And firft, it fhews that the proper fer- 
 menting Matter of every fermentable Subjedl is 
 but fmall, compared with the Quantity of Wine 
 it affords. Thus, for Example, we fee that four 
 Pounds of Raifins may be diluted, and ferment- 
 ed, with eight Pounds of Water, into what is 
 accounted a tolerably flrong Wine. And yet 
 even Raifins themfelves contain a large Propor- 
 tion of Water,befides their diredly faccharineSub- 
 ftance •, which faccharine Subftance is reducible 
 to a dry Form, as we find in Sugar. And who- 
 ever would thoroughly enquire into the Nature, 
 the Ufes, and the Means of im^roYrngvinous and 
 acetous Fermentation, cannot perhaps do better 
 than to chufe Sugar for his Subjedb *, a chemical 
 Analyfis w^hereof will fhew the Principles necef- 
 farily required in this Operation. Thefe Prin- 
 ciples appear to be an acid Salt, an Oil, andEartli 
 fo united together, as to be capable of difiblving 
 perfectly in Water. 
 
 14. Hence we alfo fee the phyfical Caufe of the 
 fermentable Nature of River- Waters which be- 
 ing kept in clofe Cafks have been obferved to 
 ferment, and their Vapor, or Spirit, to take Fire 
 at the Approach of a Candle. For much vege- 
 table Matter, as Leaves, Grafs, the Juices of 
 Plants, Cfr. being by the Rains wafhed down into 
 Rivers, fuch vegetable Matters rnufl: neceffarily 
 there run into a fermenting State, as Raifins do 
 by the Addition of Water ; the running or flux- 
 ible State of the Rivers being no Hindrance to 
 this fermentative Motion, after it is once begun 
 by Stagnation. For we fee that Beer and new 
 Wine will ferment afrefh upon being fhook, and 
 carried upon Drays, or Carts. 
 
 15. All fermentable Bodies do not require Fer- 
 ments to begin their Motion of Fermentation. 
 
 RaifmS| 
 
Of Fermentation and PutrefaBion. 123 
 
 Railins, we fee, require none ; much lefs does the 
 frefh exprefled Juice of the Grape, or other ve- 
 getable Juices, in the Summer-Seafon, or in a 
 warm Air. But all fweet vegetable Juices, that 
 have felt much of the Fire, as Treacle, or Wort 
 high boiled, Rob of Malt, Rob of Flder, or the 
 like, ufually require a conliderable Proportion of 
 a vinous Ferment to make them work. In ge- 
 neral, Ferments are no more than Matters al- 
 ready in the A6f of Fermentation, or that foon 
 run into this Ad: Of tht! firft Kind are the Flow- 
 ers of Wine, Yeaif, fermenting Beer, or ferment- 
 ing Wine, Ore. and of the fecond, arc the new 
 expreffed vegetable Juices of Summer-Fruits, Ofe. 
 
 16. Water, we find, is abfoiutely neceflary to 
 begin and procure a fermentative Motion in ve- 
 getable Subftances. For Raifins, or Sugar, being 
 kept dry, will never ferment. And this holds 
 univerfally of ail the Subjeds of vinous and ace- 
 tous Fermentation. Whence Water is an Inftru- 
 ment that muff be necelfarily employed in thefe 
 Kinds of Fermentation, whether natural, or ar- 
 tificial a). 
 
 17. As the Water which naturally, and in 
 large Quantities, perfpires from the Surface of Ve 
 getables, efpecially in hot Climates, does not go 
 off pure, but carries along with it a confiderable 
 Proportion of fermentable Matter into the At- 
 mofphere ^), there may be an adually vinous 
 Fermentation begun and carried on in certain 
 Parts of that Region, efpecially where the Winds 
 are flill, or the Air ftagnant. And what phy- 
 fica! Effeds and Ufes this Fermentation in the Ac- 
 mofphere may have, fcarce feems to have been 
 confider’d •, nor fhould they be rafhly judged of, 
 till a more thorough Enquiry is made. At 
 
 See LeSI. I. III. V. 
 
 b) See Le^. V. 
 
 Schiedam 
 
[24 
 
 ’’inegar 
 
 \ade. 
 
 Lecture the Seventh. 
 
 Schiedam in Holland^ a larger Quantity of inflamm- 
 able Spirit is faid to be obtained from Malt, than 
 in any other Place, where there are fewer Mak- 
 Dikillers. This is probably owing to the Air of 
 that Place being impregnated with the ferment- 
 ing Vapours, that continually exhale from their 
 numerous fermenting Backs and Stills. And the 
 fame is found to hold proportionably of Wines 
 fermented in large Vaults or Cellars, where many 
 Calks of Wine are at once, or fuccelTively, fet 
 to work. 
 
 1 8. Warmth, with the free Admiflion of the 
 external Air, is neceffary to expedite the Ackion 
 of vinous Fermientation , for if our Raifins and 
 Water were to Hand either in a very cold Place, 
 or to be kept entirely from the Accefs of the com- 
 mon atmofpherical Air, either no Fermentation, 
 or a very weak and flow one, would enfue ^ as 
 has been experienced. 
 
 19. The i.ees remaining at the Bottom of the 
 Cafx, in our prefent Experiment, are, if ufed 
 frefh, a true Kind of Ferment^ that will fet any 
 lefs fermentable Subjedl at work, and determine 
 its Fermentation to the vinous Kind. They contain 
 a large i'roportion of efTential Oil, and fome 
 Tartar. And hence we fee that vinous Fermen- 
 tation confiks, frji.y in an intekine Struggle or 
 Commotion of the Fluid ; and, fecondly^ in a Se- 
 paration of a grofier Part, which did not appear 
 in that Form before. 
 
 Experiment II. 
 
 Fhe Nature^ and Ufe of acetous Fermenta- 
 
 tion *, or the Method of turnmg vegetable Matters 
 into Vinegar, 
 
 20. We took the Skins of the Raifins, and the 
 Sediment left behind, after a Wine was made in 
 
 the 
 
Of Fermentation and PutrefaSUon. 125 
 
 the manner of the preceding Experiment, and 
 poured three or four times their Quantity of 
 boiling Water upon them, fo as to make a thin 
 aqueous Mixture. Then we fet the containing Cafic, 
 loofeJy cover’d, in a warmer Place than was ufed 
 for the Wine, and found the Liquor, in a few 
 Weeks time, became a clear and found Vinegar ; 
 which being drawn off from its Sediment, and 
 preferved in another Cafk, welLftopped, conti- 
 nued long perfed and fit for Ufe. 
 
 21. This Experiment fhews us a cheap The Expe~ 
 ready Way of making Vinegar from ref ufe Ma- riment tx- 
 terials ; fuch as the Huflcs of Grapes, decayed 
 Raifins, the Lees of Wine, Grounds of Ale, Beer, 
 
 which are frequently thrown away as ufelefs. 
 
 Thus in many Wine Countries, the Marc^ Rape, 
 or dry Preffings of the Grapes are thrown in heaps, 
 and fuffered to putrefy unregarded ; tho’ capa- 
 ble of affording as good Vineg ar, as the Wine it- 
 felf would make. In fome places they bury 
 Copper- Plates in thefe Hulks, in order to make 
 Verdigreafe : but this Pradlice feems chiefly con- 
 fined to the Southern Parts of France. Our pre- 
 fent Experiment fhews us how to convert them 
 to another Ufe ; and the Diredlion extends to all 
 the Matters that have once undergone, or are fit 
 to undergo, a vinous Fermentation ; for all fuch 
 Matters will afford Vinegar. Thus ail ourSum- 
 mer-Fruits in England.^ even Black-berries ; all 
 the refufe Wafhings of a Sugar-Houfe, Cyder- 
 Prelfmgs, or the like, will make Vinegar, by 
 means of Water, the open Air, and Warmth. 
 
 22. The whole Procefs, whereby this ^eProcefs 
 
 is effedled, deferves to be attentively confider’d. phyfically 
 And firft, the Liquor to be thus changed, being confiderd. 
 kept warmer than in vinous Fermentation, in 
 
 a few days begins to grow thick or turbid, 
 and without throwing up Bubbles, or making 
 
 any 
 
126 
 
 Lecture the Seventh. 
 
 any confiderable Tumult, as happens in vinous 
 Fermentation, depofites a copious Sediment. The 
 EfFedl of this Separation begins to appear firft 
 on the Surface of the Liquor, which gathers a 
 white Skin that daily increafes in Thicknefs, till 
 at length it becomes like Leather *, and now, if 
 it be continued longer in this State, the Skin turns 
 blue, or green, and would at laft grow folid, 
 and then putrefy : therefore in keeping down this 
 Skin as it grows, and thrufting it gently to the 
 Bottom of the VefTel, confifts much of the Arc 
 of Vinegar- m.akiag, efpecially from Malt. 
 
 largerOh- E is to be particularly obfervcd, that, if 
 
 Jer^ation. the Wine of our firil Experiment were not bunged 
 dovrn when arrived at its vinous State, but fuf- 
 fer’d ftill to remain open and expofed to a warm 
 i\ir, it would fpontaneoudy become Vinegar *, 
 and the fooner, if a fo mew hat greater Degree of 
 Heat, than fervedforthe Making of Wine, were 
 employed. Whenie we might have ufed the 
 Wine of our firu Experiment for this Purpofe, 
 inilead of adding Water to the Hufks and Se- 
 diment, or Lees •, but we chofe the latter Way, 
 lo fhew that even fuch refufe Matters will af- 
 ford Vinegar ; and again, to intimate how far 
 the Art of Vinegar- making may be ftill im- 
 proved, both in England where they brew a 
 Wort from Malt, and in fome Wine-Coun- 
 tries where they make their beft Wines into 
 Vinegars. 
 
 24. What we would chiefly obferve, for the 
 prefent, is, that acetous Ferfnentation requires a 
 ftronger Heat than the vinous \ and that Wines 
 having once finifhed their Fermentation, as 
 Wines, do not naturally ftop there ; but, unlefs 
 prevented by the Care of the Operator, proceed 
 directly on to Vinegars ^ where again they make 
 
 no 
 
Of Fermentation and PutrefaBion. 127 
 
 no Stop j but, unlefs prevented here alfo, fpon- 
 taneoufly go on to Vappidity, Ropinefs, Moul- 
 dinefs, and Putrefadlion. From which larger 
 Oblervation we would deduce this Axiom : That, 
 to fpeak philofophically, the Intention or Ten- 
 dency of Nature is^ to proceed from the very Begin- 
 ning of vinous Fermentation^ diredily^ in one con- 
 tinued SerieSy to PutrefalHony and thence again 
 to a new Generation \ which appears to be the 
 grand Circle wherein all natural Things are 
 moved, and all the Phyfical, or rather Chemi- 
 cal, Phenomena of the Globe produced. 
 
 25. And hence we fee how, by the Interpofi- 
 tion of Man, this general Procefs of Nature may 
 be (lopped at different Periods, with different 
 Views ; fo as to procure to ourfelves Wines, 
 Vinegars, and, as will appear hereafter, * parti- 
 cular Salts and Oils. 
 
 26. Another Corollary from the larger Ob- Corolla- 
 fervation above laid down, is, That the Word ries. 
 Fermentation has been ufually applied to (ignify 
 
 only a fmall Part of this grand Operation of Na- 
 ~ture. Thus one limits the Word to the Pro- 
 du( 5 lion of Whines; another, to the Pfodudlion of 
 Wines and Vinegars ; and feme would diftinguifh 
 it from PutrefaBion : whereas either the Term 
 Ferment atioHy or fome other, (Irould be made 
 general, and denote the Genus y or univerfal 
 Operation y whereof Vinification y Acetificationy and 
 PutrefaBiony are only Species. At leaft we 
 fhould thus attempt to follow and exprefs Na- 
 ture, in the Fa6ls that are obferved, and not 
 proceed, in an arbitrary, narrow*, or inadequate 
 Manner, to impofe Terms, and drefs out Nature 
 according to our particular Hypothefes and 
 Conceits. But the Obfervation itfelf, on which 
 
 ^ Sec below, Exp. VI. VH. 
 
 this 
 
128 
 
 V appidity 
 and Putre- 
 f action fuc- 
 ceed Fer- 
 mentation. 
 
 Phyfical 
 JJfe of the 
 Expert- 
 ment. 
 
 Lecture the Seventh. 
 
 this Do6lrine is founded, being of moment to 
 the right Underflanding of the whole Affair of 
 Fermentation and Futretadlion, we proceed to 
 illuftrate and confirm the laft Fare of it by an 
 Experiment, as the two former Farts have been 
 already a). 
 
 Experiment III. 
 
 "That Wines and Vinegars., or all fermented vege- 
 table Juices., have a natural Tendency to Putre- 
 faction, 
 
 27. We took a Gallon of thick, muddy Vi- 
 negar, produced after the Manner of our fecond 
 Experiment, and letting it ftand open, in a hotter 
 Place than was required to make it Vinegar, it 
 became in a tew days a vappid, naufeous, and 
 putrefied Liquor, throwing up a large Quantity 
 of a dry powdery Subftance to the Top, and de- 
 pofiting a iefs Quantity of a groffer Matter at 
 the Bottom *, foon after which the Body of the 
 Liquor became clear again. 
 
 28. We might fhorten the prefent Experiment, 
 and fave the Trouble of making either a Wine, 
 or a Vinegar, to fliew it. f or if a Quantity of 
 Mujl were fet in an open Veffel, in a hot Stove- 
 Room, where the Air had free Accefs, the 
 Work would foon be performed, and theputri- 
 fied Liquor be produced almoft at once, with- 
 out flopping at the State either of Wine or Vi- 
 negar*, according to the larger Obfervation de- 
 liver’d above b). 
 
 29. The p'^efent Experiment has a confide- 
 rable philofophical Ufe, as affording Light to 
 the Underflanding, and leading us tar into a 
 Knowledge of our Subjed. And ( i.) it gives us 
 the phyfical Reafon why Wines and Vinegars, 
 
 a) See Exp. I. II. 
 h) §.24, 26. 
 
 unlefs 
 
Of Fermentation and PutrefaSiion. 129 
 
 unlefs made exceeding flrong, will not keep, but 
 corrupt and putrefy, in hot Countries. For the 
 Heat being there fo great, as to keep the lighter 
 feculent Parts of thofe Liquors fufpended for ibme 
 time in the Body of the Liquor, Corruption 
 (which proceeds from a tumultuary Motion of all 
 the different Parts of a compound Body toge- 
 ther a neceffariiy enfues. 
 
 30. (2.) Hence alfo we learn the phyfical Rea- 
 fon why Wines and Vinegars require to be racked 
 from their Lees, in order to preferve them found, ^ 
 or keep them from running into Putrefadion, to 
 which we find they are ftrongly inclined; the 
 Tendency of Nature being ever confiant in urging 
 them to that State. And the Cafe appears to be 
 much the fame in animal, and even mineral 
 Subftances; as we fhall fee hereafter h), 
 
 31. (3). This Experiment, therefore, furnifhes 
 us with a Rule for preferving vegetable Liquors 
 from the laft Stage of Fermentation, that is, Pu- 
 trefadion or Corruption ; viz, by firfl: clarify- 
 ing, and afterwards fecuring and defending them 
 from the open Air, and too much Heat. Thus, 
 for example, we can preferve the natural Juices 
 of Quinces, Oranges, Lemons, Plants, found 
 and uncorrupt, by fir ft clearing them of their 
 grofier Parts by the Fiitre ; or in fome Cafes by 
 Boiling and common Straining ; then putting them 
 up in Giaffes, pouring Oil on the Top, and fetting 
 them in a cool Place. And in the fame Manner 
 we find fome of the more delicate and curious 
 Wines are long prel'erved found and fprightly : 
 for the grofier Feculencics being firft removed, 
 
 the Oil poured on the Top prevents the external ^ 
 
 Air from entering; and by keeping the GlafTes 
 
 a) See §. 27. and hereafter 5 ’at^'). VI, and VII. Ses alfa *■ 
 the Iiord Bacon'^ Syl-va Sylvarum pajjim, 
 
 b) Exp. VII. VIII. 
 
 K 
 
 fro.m 
 
130 
 
 Lecture the Seventh. 
 
 from the Sun, or open Day, too much Heat does 
 not come at them. 
 
 Vhfical 32. (4) it IS here remarkable, what a large 
 and Che- Qjanclty of Iblid, earthy Matter is naturally con- 
 tamed in all fermentable Liquors. Thus, if a 
 pellucid Solution of the fineft Sugar in Water be 
 expofed to vinous Fermentation, it foon grows 
 turbid, throws an earthy Skin to the Top, and 
 depofites much terreftrial Matter at the Bottom in the 
 Form of Lees. If the Wine be now drawn off 
 clear and expofed to acetous Fermentation, here 
 again it throws off much terreftrial Matter, both in 
 the Form of a Skin at Top, and of Lees at the 
 Bottom. Thirdly, if tranfparent Vinegar be ex- 
 pofed to putrefactive Fermentation, here again it 
 feparates a confiderable Qtiantity of Earth, both 
 at the Bottom and at Top. All which fhews that 
 the Separation of a grofs Matter is effential to 
 thefe feveral kinds of Fermentation, and that a 
 copious Earth may lie concealed in fermentable 
 Juices, and tranfparent Fluids, till it finds an Oc- 
 cafion of manifefting itfelf to the Senfes. 
 
 Chan- Before we proceed to animal and mine- 
 
 ^cedbyFer- Fermentation, it is proper to examine what 
 mentation, ^^e the Changes wrought upon vegetable Sub- 
 jects by vinous and acetous Fermentation. This 
 we may find, in fome Meafure, by comparing 
 Muft, or a bare Solution of Raifins in Water, 
 with the Wine and Vinegar which the fame 
 Muft, or Raifins and Water afford, in Vinifica- 
 tion and Acetification *, and in this Light they 
 may be compared by the bare Ufe of the Senfes; 
 but their internal and effential Differences will 
 better appear by a chemical Analyfis, or Diftilla- 
 tion. 
 
 34. Muft, or a Solution of Raifins in Water, 
 which makes a Kind of Muft correfponding to 
 the natural Juice of the Grape, is a fweet, clam- 
 my 
 
Of Fermentation and PutrefaSlion. 1 3 1 
 
 my and fomewhat odorous Fluid, which being 
 committed to Diftiilation affords not the lead in- 
 flammable Spirit. But after having pafTed thro’ 
 the Courfe of vinous Fermentation, it acquires 
 feveral Properties it had not before. For ex- 
 ample: it is more tranfparent and thin-, lofes of 
 its Sweetnefs j has fome Degree of Acidity and 
 Roughnefs; proves more odorous, and affords a 
 large Proportion of inflammable Spirit as ap- 
 pears by the following Experiment* 
 
 Experiment IV* 
 
 ^hat vinous Fermentation produces an injlammahlc 
 Spirit, 
 
 35. We took three Gallons of new Wine, 
 procured from Raifins and Water in the manner 
 of our firft Experiment, and committed it to the 
 Alembic or Still, which being made to work 
 gently, till the Liquor that came over, being 
 thrown upon the hot Still-Head, would no longer 
 take Fire by applying the Pdame of a Candle 
 to the rifing Vapour, we thus obtained a con- 
 fiderable Proportion of Brandy^ and a weaker 
 Spirit, 
 
 36. This Experiment fhews us the common 
 Method of making Brandies in Wine- Countries, 
 
 or a Spirit from Malt, Melaffes, Cyder, i^c,ment, 
 in others. For the fined French and Rheniflj 
 Brandies, the Rums and the Arracks of the In- 
 dies^ are obtained in the Manner of this Experi- 
 ment ; all of them being ufually didilled a fecond 
 time over, and made up^ as they call it, with . 
 Water, or the weak aqueous Liquor of the fecond 
 Running, as in our prefent Experiment, to a 
 certain Strength, or fuppofed Standard, termed 
 faleable Proof, 
 
 K 2 
 
 37. This 
 
132 
 
 Proof in 
 
 Spirits 
 
 •fjohat. 
 
 Philojdphi- 
 
 calVfe, 
 
 Spirit of 
 Wine honv 
 btained. 
 
 Lecture the Seventh. 
 
 37. This Proof is judged of by the Head, or 
 Crown of Bubbles, rifing upon the Surface of the 
 Liquor when fliook in a long (lender Vial, and by 
 the Manner wherein thefe Bubbles vanifh. For if 
 they are too large and vanifh too foon, the Spirit 
 is deemed above Proof', if too fmall, and they 
 go off too foon, it is laid to be below Proof 
 But this is a fallacious Method of Judging; be- 
 caufe there are certain knov/n Ways of making a 
 Spirit bear this Trial, when it is in Reality either 
 above or below Proof. P^or the proper Meaning 
 of the W^ord i^s, that a Proof - Spirit fhould 
 contain about one half Water, and the other half 
 Alcohol a ). 
 
 38. The philofophical Ufe of the Experiment 
 is to fliew, that an inflammable Spirit is produced 
 by the Adtion of vinous Fermentation, from 
 a vegetable Subjed and Water, wherein no 
 Signs of any fuch Spirit before appeared. In- 
 fomuch that this may be juflly efteemed the 
 Criterion, or infeparable EfFedl, of vinous Fer- 
 mentation. 
 
 39. The Ways of obtaining this inflammable 
 Spirit, to the bed Advantage, will be confldered 
 hereafter h),. In the mean time it may be ob- 
 ferved, that this Spirit being rediflilled, fo as to de- 
 prive it totally of its aqueous Part, is the Spirit 
 of Wine, or Alcohol, vvhofe diflTolving Power 
 was fhewn, in the iafl Ledlure upon Menftru- 
 urns c ) ; and this Method is the only one that 
 is known of procuring it. For no Subjeds but 
 thole of the vegetable Kingdom are found to af- 
 
 a) See this Matter farther explained in Lebt. XII. ExpAY. 
 See alfo Led. I. Exp. VII. 
 
 b ) Led. XI. and XII. 
 
 c) See Led, VI, Exp. II. 
 
 ford 
 
of "Fermentation and PutrefaBions 133 
 
 ford it ; and that only by means of a previous 
 vinous Fermentation. 
 
 40. It fhould iikevvife be obferved, that thisT'^^^t^^ 
 Alcohol is one of the mod eflential Parts of Wine ; the Spirit 
 fo that, when it is withdrawn, the Wine lofes 
 its Nature ; as we fee by the Remains of the pre- 
 fent Experiment. And when properly ufed, it 
 is a certain Remedy for mod Difeafes incident to 
 Wines ; as keeping them found and free from 
 Corruption. Whence we have another Rule for 
 preferving vegetable and animal Subdances from 
 Putrefadlion. For this Liquor proves a kind of 
 Balfam to them all, and is accordingly ufed, with 
 Succefs, for preferving even animal Subdances ; 
 as we fee in anatomical Preparations, 
 
 Experiment V. 
 
 ^hat acetous Fermentation aholijhes the inflammable 
 , Spirit produced by vinous Fermentation. 
 
 41. We put a C^art of fharp Vinegar into a 
 Glafs Retort, and didilled, in a Sand-Heat, withy^/^^^^ 
 Degrees of Fire,- into a Glafs Receiver, but Alcohol 
 found not the lead inflammable Spirit come over; 
 
 only an acid aqueous Liquor, commonly called 
 diftilled Vinegar ; which, indead of burning, quen- 
 ches Fire. 
 
 42. Hence it appears, that acetous Fermenta- , 
 tion has a very diferent Effedt from the vinous; 
 and that the inflammable Spirit produced in the jnent. 
 former, is either concealed, altered, exhaled, de- 
 droyed, or fome Way abolifhed, in the latter. A 
 part of this Spirit is unquedionably exhaled by the 
 Heat employed in Acetiflcation; yet Part alfo 
 remains behind under a different Modification, 
 
 fo as to be recovered by Art in an inflammable 
 Form; as we find by didiiling the Sugar of 
 K 3 Lead^ 
 
12 ^ Lecture the Seventh. 
 
 Lead^ which is only Lead dilTolved in Spirit of 
 Vinegar. 
 
 43. Our Experiment affords us a Criterion of 
 acetous Fermentation, as before we had of the 
 vinous. For if an acid uninflammable Liquor 
 comes firfl; over by D»ftillat‘on from a vegetable 
 Subje6t, previoufiy fermented, this wdll determine 
 that Fermentation to have been of the acetous 
 Kind. 
 
 44 Thus, therefore, we are plainly led to 
 allow of two very different kinds of Fermenta- 
 tion, in the fame vegetable Subjed: ; and we con- 
 ceive that fome other Species may be found upon 
 due Enquiry. 
 
 Experiment VL 
 
 # 
 
 That vegetable Matters turn of an animal Na^ 
 ture by a hot Fermentation^ or Putrefaction, 
 
 p r 45 We took a large Quantity of frefh, green 
 Cabbage-Leaves, and prdied them hard down 
 getables. With Weights in an open Tub, bored full of 
 Holes on the Sides and fet in a warm Place. By 
 Banding in this State for fome Days, the Leaves 
 conceived a Heat in the middle, which fpread to 
 the more external Parts, till at length' nearly the 
 whole was converted into a pappy, putrefied Sub- 
 ftance, whofe Confiftence would not well fuffer it 
 to feparate into a thicker and a thinner Part. 
 This Subffance being diftilled in a Glafs Re- 
 tort, afforded the iame Kind of volatile Salt 
 and Oil, as if it had been an animal Subfta nee 
 7 heExfe- 46. This Experiment is general, and fucceeds 
 rimeni m all tender, juicy, vegetable Subjedls ; fo 
 
 uM. acid and alkaline Tribe of Plants, 
 
 the fweet and the bitter, the aftringent, and e- 
 moliient, r^blve into this fame pappy, pu- 
 trefied 
 
of Fermentation and PutrefaSilon. 135 
 
 treficd Subflan'Ce. We obferve it alfo in Hay 
 that is (tacked wet; in Horfe-luter thrown on 
 Heaps; in the Grape-Hu(ks, or Apple-Pumice, 
 after prelfing for Wine or Cyder; and the larger 
 the Heap, and the greater Weight the Matter 
 fuftains, the greater the Heat; provided the Accefs 
 of the Air be not prevented. 
 
 47. Hence we fee the Way employed by Na- /« jjfe, 
 ture for changing all vegetable into animal Sub^ 
 fiances^ or of reducing the Matters of both King* 
 doms to a Similarity; fo that the one may be ufed 
 
 for feveral Purpofes inftead of the other. And 
 thus Nature annually makes large Quantities of 
 Compoft, from the refufe Weeds, Leaves, Trafh 
 of the Fields, Woods, and Gardens ; for this ve- 
 getable Matter thus putrefying, and becoming fofc 
 and pulpy, is eafily diluted by the falling Rains, 
 and thence dirperfed over the Face of a Field, and 
 carried into the Pores of the Earth. And thus 
 the Chemift may, by Diftillation from fuch putre- 
 fied vegetable Subjeds, procure volatile Salts and 
 volatile Spirits, hardly to be diftinguifiied from 
 thofe of Hartfhorn, at lead: the volatile Salt 
 and Spirit fo obtained might ferve together with 
 Sea-Salt, for making of Sal- Ammoniac For 
 it appears that the Matter of the fixed Salt in 
 Vegetables is, by this Operation, truly volatili- ^ 
 zed. Whence not a Grain of fixed Salt can be pro- 
 cured from the largeft Quantity of this putrefied 
 Matter, provided the Operation were compleatly 
 performed. 
 
 48. This Experiment has various Ufes, not 
 only in Trades., but alfo in natural Philofophy 
 and Medicine. And firfl, it fhews an artificial 
 as well as natural Method of converting any, 
 or all of the different Subjeds of the vegetable 
 
 a) See he£i, XX. I. 
 
 K 4 
 
 Tribe 
 
136 Lecture the Seventh. 
 
 Tribe into the fame undiftinguifhabie' Subftance, 
 totally deftroyingall the fpecific Differences which 
 before diferiminated that great Variety. And the 
 fame Obfervation reaches allb to animal Bodies, 
 as we fliall fee hereafter 
 
 Inthcani. It alfo throws confidcrable Light upon the 
 
 malOeco- p^ocefs of animal Digsftion, as performed in the 
 Stomach and Inteftines ; it fhews us the Nature 
 of Gangrenes, Mortifications, and carious Bones 
 in the Body ; and the phyficai Realbn why no 
 fixed Salt Is found in the Blood, Bones, or Flefh : 
 All which Particulars may be farther iiluffrated 
 and confirmed, by confidering the like Frocefs in 
 an animal Subjed. 
 
 II 
 
 Experiment VII. 
 
 animal Bodies naturally undergo a Fermenta- 
 ticn^ or Putrefadiion^ after Death, 
 
 Animal 50. If any large animal Body, as that of a . 
 Putrefac- Horfe or a Dog, for example, be expofed in a 
 non, diQ2Ld State to the open Air and ^the Summer’s 
 Sun, it begins in a few Days to fwell, purge, and 
 emit a naufeous Stench. At length the Form of 
 the Carcafs is defroyed by the Commotion, and 
 refolved into a putrid, fetid, fercoraceous Matter; 
 a large Part in the mean Time flying off into the 
 Air, fo as to leave but a fmali Proportion of a 
 mucilaginous, pappy Subftance, which foon grows 
 dry, or turns to a Kind of Earth. But a Quantity 
 of this Matter being colleded before it grows 
 dry, and diftilled, it is faid to afford the burn-« 
 ing PhofphGrus^ as putrefied Urine is known 
 tb do. 
 
 Exp. VII. 
 
 51. This 
 
of Fermentation and Putrefaction. 137 
 
 51. This* Experiment or Obfervacion is uni- Extended- 
 verfa), and holds .equally of Birds, Beads, and 
 
 Fifh. Whence Rivers, the Ocean, and the At* 
 mofphere itfelf, muft neceflarily be impregnated 
 with fermenting, putrefying, and putrefied Par- 
 ticles, which mixing with other Matters, and 
 being difperfed through the immenfe Bodies of 
 thofe Fluids, they undergo therein fuch Changes, 
 whether by uniting with the Salts of the Air and 
 Ocean, or otherwife, as prove not unfrequently 
 deflrudive or noxious to the Creatures that in- 
 habit thofe Elements. For this putrefied Mat- 
 ter appears to be in itfelf a Kind of Poifon, in- 
 feding the Air wherein it fpreads ; fo as to oc- 
 cafion peflilential Difeafes near the Places where 
 great Battles have been fought, when the un- 
 buried Carcafes of the Slain thus refolve and go off 
 into the Atmofphere. Many other Inftances we 
 have of the poifonous Nature of putrefied ani- 
 mal Subfiances, in rotten Eggs, mortified Flefh, 
 and the like : whence this leems to be another 
 particular Species of Fermentation, 
 
 52. It has been difputed, whether there be a Fermenta- 
 real Fermentation in the prefent Cafe. But (up- tion deter- 
 pofing this not to be a Difpute about Words, it 
 fhould feem that there is a proper Species of 
 Fermentation, peculiar to animal Subjects, as 
 
 there is one peculiar to Vegetables. Till this Point 
 be fettled, we fliould not lay down vegetable 
 Fermentation, as the Ted and Standard of Fer- 
 mentation in general, and fo judge of all other 
 Kinds according as they approach to, or recede 
 from, this Standard. For want of didinguifhing 
 in this Cafe, all true Fermentation Teems denied 
 to the Blood and Juices, circulating in a liv- 
 ing animal Body, as well as to the Sap of Ve- 
 getables. But were the Enquiry into Fermen- 
 tation profecuted in its full Latitude, and not 
 
 arbitrarily 
 
138 
 
 Ch^mfiry 
 of Nature 
 in Bodies. 
 
 Mineral 
 
 Fermenta- 
 
 tioJi, 
 
 Lecture the Seventh. 
 
 arbitrarily confined to any fingle Species, per- 
 haps many natural and art’ficial Operations 
 would prove to be adtual Fermentations. To 
 fay that there is no Fermentation in the Blood, 
 because it affords no inflammable Spirit upon 
 Diftillation, is in effedl the fame as to fay that 
 B'ood is not Wine. Whereas the Queftion is 
 not whether there be a vegetable Fermentation in 
 the Blood, but whether there be not an animal 
 one \ the Criterion whereof is the Produdlion of 
 a volatile urinous Salt, as the Produdion of an 
 inflammable Spirit is the Criterion of vinous Fer- 
 mentation. 
 
 53. And here is a Door opened for enquiring 
 into the Chemiftry of Nature, as it is exercifed 
 in the Bodies of Men ; fo as to difcover the na- 
 tural Means whereby vegetable Subftances taken 
 in at the Mouth, by the Way of Aliment, are 
 prevented from running into vinous or acetous 
 Fermentation •, but are, on the contrary, changed 
 into a balfamic, undtuous, and milky Liquor, or 
 Chyle, that turns red in the Arteries, recruits 
 the Blood, and nourifhes the Body. For all this 
 feems to be the Effedt of a peculiar 
 mentation^ the Laws and Procefs of which are 
 little confidered. And in this View, the feveral 
 Juices of the Body, as the Saliva, Bile, Pan- 
 creatic Juice, &c. may be regarded as animal 
 Menjiruums^ adled upon, and made to adl in the 
 Body, by determinate Motions, for determinate 
 Ends. 
 
 Ill, 
 
 Experiment VIII. 
 
 That there may be a Kind of Fermentation in mine- 
 ral and metallic Bodies. 
 
 54. We took an Ounce of Lead and as much 
 Billnuth, and melted them together in an Iron 
 
 Ladle; 
 
permentation and Putrefaction. 139 
 
 Ladle; then heating two Ounces of Quickfilver 
 in another Ladle, we mixed all the three me- 
 tallic Matters together as an Amalgam ; which, 
 when cold, appeared perfedly uniform or homo- 
 geneous, and totally pafled thro’ the Lores of 
 Leather in a running Form. But this Mixture 
 being fuhered to cool, and (land quiet for fome 
 Hours, a grofs Matter feparated from it by De- 
 grees, and floated upon the reft ; which was left 
 io thin and fluid, as to pafs through Leather, leav- 
 ing the grofs metallic Matter behind. 
 
 55. Hence it fliould feem that even metal- pxfe- 
 lic Matters may have their peculiar Fermenta- riment ex- 
 tions, as well as vegetable and animal Subjedls. 
 
 For when the prefent Experiment comes to be 
 carefully confidered, it appears to have all the 
 Requifites of Fermentation. For here is, (i.) 
 a fluid Form, (2.) an uniform Matter, (3.) an 
 inteftine Motion, and (4 ) an adlual Separation 
 of a grofler Matter, leaving a thinner behind. 
 
 All which Particulars we have found to hold in 
 the feveral Species of Fermentation above exami- 
 ned. 
 
 56. There are many more Inftances of an 
 apparent Fermentation in mineral Bodies, one or 
 two whereof it may be proper to mention. Thus, 
 if an aqueous Solution of the common green Vi- 
 triol be expofed to the Air in the Summer-time, 
 and kept continually fupplied with frefh Water 
 as the former exhales, the grofter metallic Part 
 of the Vitriol will fubflde, and the reft gradually 
 fhoot upwards all round the Veflel, in Form of 
 an undluous, crufty Matter ; till the whole Body 
 of the Vitriol is thus fuccefiively fo altered that' 
 the Part fhot into the crufty, undtuous Form, 
 v/ill neither become Vitriol again, nor corrode 
 any frefh Metal ; and in ail ’ other Refpedfs 
 it appears a different Thing from Vitriol. And 
 
 hence 
 
140 • Lecture the Seventh. 
 
 hence feem to proceed the Complaints of the 
 Makers of Vitriol, that in rainy, windy, and cloudy 
 Weather, their Vitriol-Stones, which lie open to 
 the Air, .will not fometimes yield a folid cryftal- 
 line Vitriol, but only an unduous Matter. This 
 may therefore appear to be a Fermentation in all 
 its Forms, as being attended with a fpontaneous 
 inteftine Motion, a fpontaneous Separation of 
 confbituent Parts, and a remarkable Alteration 
 of the Subjed. 
 
 57. It alfo makes to the prefent Purpofe that 
 folid and hard Pyrites, or Vitriol-Stones, being 
 expofed to the Air and moiftened with Water, 
 will, like a vegetable Subjed^), grow hot, fume, 
 and even take Fire, as was obferved in our 
 fourth Ledure, and afterwards, afford Vitriol •, 
 a Thing very different from the Stones them- 
 felves^j. So that, upon the whole, we may 
 conclude, that in a proper Senfe, there is an 
 adual Fermenlation cxercifcd, not only in the 
 vegetable and animal, but alfo in the mineral 
 Kingdom. 
 
 V. 
 
 Axioms and Canons. 
 
 I. All the Inflances being duly confidered, 
 and a large View of Things taken in, we may 
 define Fermentation^ in general, a fenfible inter- 
 nal Motion of the confiituent Particles of a 
 moifl, fluid, mixed, or compound Body ; by the 
 Continuance of which Motion, thofe Particles are 
 gradually removed from their former Situations, 
 or Combinations; and again, after fome vifible 
 Separation is made, joined together in a diffe- 
 rent Order and Arrangement. And thus the 
 
 a) See above, Exp. VI. 
 
 ^ ) See Leet. IV. Exp. V. 
 
 whole 
 
of Fermentation and PutrefaEHon. 
 
 whole Procefs of Fermentation confifts of two 
 different Operations, viz, an Analytical one, 
 -whereby the Particles are refolved, and a Syn^ 
 thetical one, whereby they are new ranged : So 
 that whenever thefe two different Effects are 
 found to be produced, in diredl Sequence, with 
 the Circumftances above deferibed, we need not 
 fcruple to call the Operation by the Name of 
 Fermentation^ whether it happen in the Blood, ^ 
 or other animal, vegetable, or mineral Sub- 
 ftances a\ 
 
 2. That all feparable, mixed, or compound 
 Bodies may be the Subjects of this general O- 
 peration ; but that the eafier they are feparable 
 by Means of Water, Air, and Hear, the more 
 readily they ferment h). Thus the fweet or fac- 
 charine Part of Malt, more readily diflfolving 
 in warm Water, ferments eafier than unmalced 
 Corn, which is more clammy and will not 
 difffolve fo foon. • And hence the Flefh of ani- 
 mal Bodies putrifies fooner than the Bones. And 
 this appears to hold in all Inftaiices c), 
 
 3. That this general Fermentation is divifi- 
 ble into many diftin6l Species, particularly in- 
 to vegetaUe^ animal^ and mineral d)\ the vege- 
 table Kind again into vinous^ acetous^ and pi- 
 trefa 5 Hve ; the vinous again into mucilaginous, 
 mouldy, and putrefadive ; and fo of the ace- 
 tous, (Ac, Whence we may deduce a Canon for 
 adjufting all the different Species of Fermenta- 
 tion *, which being once fixed might put an 
 End to infinite hypothetical Difputes upon this 
 Subjed, and lead to farther Difeoveries both 
 in Nature and Art. 
 
 a) See the whole Ledure, ^afjim. 
 
 See Exp, I. VI. 
 
 c) See Exp, 1. VI. VII. 
 
 dj See the whole Ledure, pajfim. 
 
 I4I 
 
 4, That 
 
142 
 
 Lecture the Seventet. 
 
 4.. That it is in the Power of Man to pre- 
 vent, flop, and rcgiiLle thefe natural Operations 
 at any afTigned Point of Time. Indeed it is thus 
 we come by our Wines and Vinegars ; it is 
 thus that Men difeovered the Art of Embalm- 
 ing ; It is thus we prefer ve many vegetable, 
 and animal Juices, in their natural or unfer- 
 mented State ; It is thus we preferve Yeaft, 
 and Wine-Lees, Subje6ls extremely apt to pu- 
 trefy ; It is thus we can at any Time flop the 
 Courfc of vinous Fermentation, and produce a 
 fweet, or half fermented Wine ; It is thus we 
 ‘cure the Fretrings, or other Difeafes of Wines ; 
 and thus we flop Mortifications in the Body, 
 and Caries in the Bones. And mod of the Ar- 
 tifices employed for thefe Purpofes, depend upon 
 a Knowledge and Regulation of the phyfical 
 Caufes and Inflruments that produce the Change; 
 which Caufes and Inflruments, as we above dif- 
 eovered, are chiefly. Hear, Moiflure, and the 
 external Air a), 
 
 5. That a faccharine Matter is the Balls of 
 * Wines, Vinegars, and inflammable Spirits b). 
 
 6 . That a great variety of found, perfeft, and 
 wholefome Wines may be made, in Countries 
 that do not naturally afford Grapes, by a prudent 
 Ufe of Sugar, or Raifins and Water c). 
 
 7. That the Matters called Ferments are of 
 Ufe in beginning, regulating, and determining 
 the Species of Fermentation c). Thus frefh Yeafl: 
 determines the Fermentation of Wheat - Flour 
 to make our common Bread, which would 
 prove of another Kind, if the Flowers or Lees 
 of Vinegar were ufed. And thus fpecifle or de- 
 
 Cl ) See the whole Lefture, 
 
 h) See I. 15. &;c. ■ 
 
 c) See Exp. I. 
 
 terminate 
 
of Fermentation and PutrefaBion. 143 
 
 terminate Ferments have their correfpondent Ef- 
 fects. If Sugar, Honey, Manna, Treacle, or 
 new Wine be added to Vinegar, themfelves are 
 foon changed into Vinegar, without (lopping to 
 make Wine ; becaufe the acetous Ferment, or Vi- 
 negar, over-rules them. And fo Vinegar is foon- 
 eft made in a Cafk that has before contained the 
 fame Liquor. And if the beft Wine were put 
 into a Cafk that had held putrefied Vinegar, 
 the Wine would not now make Vinegar, but 
 immediately run into Corruption. So great and 
 fo decifive a Power have fpecitic Ferments ; the 
 Ufe whereof is therefore evident, and may afford 
 confiderable Rules in Chemiftry, pra( 5 lical Phi- 
 lofophy, and ilrts. 
 
 8. Thar the Degrees of Fermentation differ 
 with the Degrees of Heat employed a ), Thus 
 we faw vinous Fermentation required a lefs De- 
 gree of Heat than the acetous ; the acetous a lefs 
 than the putrefadlive; which latter may even 
 confift with a Degree of Ignition b). 
 
 9. That a particular Kind of Fermentation 
 may be carried on in the living Bodies of Ani- 
 mals and Vegetables, which are largely fup- 
 plied with the requifite Inftruments of Fer.men- 
 tation, viz. Water, Air, and Heat: And in Fact 
 both Vegetables and Animals appear to have an 
 inteftine Motion in all their circulating Fluids, 
 which continually depofice a groffer Matter in 
 the Canals and Parts they move through. Whence, 
 by our Definition of Fermentation c)^ this natu- 
 ral A6t may be accounted a Species of Fermenta- 
 tion, producing a Change in the nutriiuental Mat- 
 ter of Vegetables and Animals, and converting it 
 into their own Subftance. 
 
 a) See Exp. I, II, III, IV, V, VI, 
 
 b) See Exp. VI. 
 
 c) See Jx. I. 
 
 10. That 
 
144 
 
 Lecture the Seventh. 
 
 10. That when Vegetables or Animals die, 
 there foon begins a different Kind of Fermenta- 
 tion in all their Parts *, tending now not to the Re- 
 pair, but to the entire Deftrudlion, of their orga- 
 nical Veffels, the confufed Mixture of their folid 
 Parts and Juices, and a Volatilization of their 
 whole Subftance^^J. 
 
 1 1 That dry or folid Bodies cannot, in that 
 State, undergo a proper Fermentation : for tho* 
 they may in that State be feparated into minute 
 Particles, yet they cannot range themfelves toge- 
 ther in any new Order, nor depofite a greffer Part, 
 without being agitated by fome Fluid, or fufpend- 
 ed therein for fome Time. And hence, in over- 
 heated Mines, the Ore is thus analytically de- 
 ftroyed, and cannot range itfelf into a metalline, 
 or any other regular Order again, for want of 
 the requifite Moifture or Fluidity *, whence the 
 Matter appears like a Heap of rotten Earth, or 
 what the Miners call Dead Metal h) of which 
 we have a remarkable Inftance in the over-heated 
 or fired Mixture of Sulphur and Iron-Filings c). 
 
 12. That the terreftrial, marine, and atmorphe- 
 rical Regions have each their proper Fermenta- 
 tion^ different in Kind, and fubdivifible into par- 
 ticular Species, whereby the Changes of all Bodies 
 one into another are naturally performed d) % 
 And that in Imitation hereof, by a thorough 
 Knowledge of the natural Agents that produce 
 thefe grand Effedls, Art likewife may produce 
 extraordinary Changes in Bodies e). 
 
 a ) See Exp. V. VI. 
 
 F) See Exp V III. 
 
 c) See XIX Exp.Wl. 
 
 d) See the preceding Ledures upon the Elements, See 
 alfo that upon Menjlruumsy and the leveral Experiments in 
 the preient Lediure, 
 
 e) See Ledi, I. pajjim. 
 
 L E C- 
 
C'145 1 
 
 L E C T U R E VIII. 
 
 CONTAINING 
 
 Analytical Chemiftryi or^ the Art of Ana-> 
 lyf ng Vegetable^ Animal, and Mineral Sub- 
 fiances, and refoking them into difierent 
 Parts or Principles, 
 
 • L 
 
 i. H E whole of Chemiftry may be com- Suhjeei, 
 
 I prehended under the Arc of refolving 
 Bodies into their Principles, and of 
 compofing new Compounds from thofe Principles, 
 by Means of the common Elements, Fire, Air, 
 
 Water, Earth, and particular Menjiruums. We 
 fhall accordingly in our prefent Ledure, endea- 
 vour to enquire into the Bufinefs of chemical Re- 
 folution, in the vegetable, animal, and mineral 
 Kingdoms, with a View to difeover what ufeful 
 Principles may be thence obtained ; intending, in 
 our next Ledure, to confider the correlative Bu- 
 finefs of Compofition : fo that the two together 
 may contain a fummary Account of the Nature, 
 
 Office, and Ufe, both of analytical and fynthe- 
 tical Chemiftry ; of which the one takes Bodies 
 to Pieces, or reduces them to their component 
 Matters, and the other, by putting thefe Matters 
 or different ^Pieces together again, in various 
 Manners, forms a large Set of new Produdions, 
 that would be unknown to Nature without the 
 Interpofition of Art. And fuch Productions, for 
 Inftance, are. Brandy, Soap, Glafs, &c. 
 
 2. But before we enter upon the Enquiry it- Prinripi^^ 
 felf, it is neceifary we Ihould diftinCtly explain ^ujkat. 
 
 L what 
 
146 
 
 Lecture the Eighth. 
 
 what we mean by the Word Principle^ about 
 which many Difputes have been railed We 
 mull therefore oblerve, that the more intelligent 
 among the modern Chemifts do not underftand 
 by Principles thofe original Particles of Matter, 
 ot which all Bodies are by the mathematical 
 and mechanical Philofophers fuppofed to confifl. 
 Thofe Particles remain undifcernible to the Senfe, 
 tho’ affilled with the molt finifhed Inftruments ; 
 nor have their Figures and original Differences 
 been determined by a juft Induction. Leaving, 
 therefore, to other Philofophers the fublimer Dif- 
 quifition of primary Corpufcles, or Atoms, of 
 which many Bodies and Worlds have been formed 
 in the Fancy, genuine Chemiftry contents itfelf 
 with grOiier Principles, which are evident to the 
 Senfe, and known to produce Effe6ls in the Way 
 of corporeal Inftruments. And thefe groffer 
 Principles are every Way fufheient to anfwer the 
 Purpofes of philofophical Chemiftry, which con- 
 fifts wholly in Experiment, and the Explanation 
 of Fafts and fenfible Operations. Where, by the 
 Way, it may be obferved, that Chemiftry is an 
 Art extremely well fuited to the Nature of Man, 
 as it requires nothing more than the Ufe of fuch 
 Faculties as he evidently finds himfelf poffeffed 
 of. But when once we leave the Oracles of Senfe, 
 and introduce metaphyfical Speculations and No- 
 tions into Chemiftry, it then becomes a corrupt 
 Fountain of Flypothefis and Illufion. To redi- 
 fy Chemiftry, therefore, the Rule is to keep clofe 
 to the Information of our Senfes, the Laws of 
 Induvftion, and the Ufe^of material and fenfible 
 Principles. 
 
 3. Thefe fenfible Principles, fo far as we know 
 them, are fignihcantly expreffed by the common 
 Words, fVater., Earth Salt., Sulphur., and Mer- 
 airy : to which might be added the Air, if a Way 
 
 were 
 
of Analytical Chemiftry. 147 
 
 were known to fix it, fo as to render it more fen- 
 fible, tangible, and corporeal 
 
 4. By Water we underftand a fenfible, tranf- Water. 
 parent Liquor, without Tafle or Odour*, that 
 freezes with a certain Degree of Cold, and liqui- 
 fies from that State with a certain Degree of Heat ; 
 
 that extinguilhes Fire, By the Chemifts this 
 is otherwife called Phlegm. 
 
 5. By Earth we underftand an infipid, dry. Earth. 
 powdery Subftance, that will neither dilTolve in 
 Water, nor burn away in a ftrong Fire ; but, with 
 
 the Addition of fixed Salt, melts into Glafs. 
 
 6. By Salt we underftand any fenfible Body^^^^* 
 that readily diffolves in Water, taftes fharp or 
 pungent upon the Tongue, and has a great Dif- 
 pofition to unite with Earth, fo as to appear in a 
 Iblid Form \ as in common Salt, Alum, ^c. 
 
 7. By Sulphur we mean any Matter that will 
 readily burn and difappear in the Fire, and that 
 will not eafily, or of ftfelf, mix with Water. 
 
 8. And laftly, by Mercury we underftand a Mercury. 
 fenfible Body that has the Fluidity, Gravity, and 
 Appearance of common Quickfilver. 
 
 9. We do not lay down thefe as adequate Defi- 
 nitions, but only -as fenfible Marks whereby the 
 Things meant may be readily known and diftin- 
 guifhed for ordinary Ufe. Juft Definitions can 
 be drawn only from a full and perfedt Difcovery 
 of the Nature and Properties of Bodies, which 
 we are far from knov/ing ; nor do we ufually meet 
 with any of thefe Principles in a pure and per- 
 fed State, unmixed with other Bodies. When 
 they appear to the Senfes to be thus far purified, 
 they are the Principles \>e mean, or what we 
 
 See Le^. III. Exf X. 
 
 L 2 
 
 empha- 
 
148 
 
 Worm- 
 
 fiuood 
 
 fwaly/ed. 
 
 7he Expe- 
 riment 
 7T ge- 
 neral 
 
 Lecture the Eighth. 
 
 I 
 
 emphatically call the Chemical Principles-^ tho’ 
 they may be every one of them deftru6lible, 
 as to that Form : but then they ceafe to be che- 
 m.ical Principles. 
 
 10. And thus we have endeavoured to fettle 
 the chemical Meaning of the Word Principles^ 
 and to lay down Marks or Criterions for difeover- 
 ing and diftinguifhing them, when we meet with 
 them hereafter in the following Experiments. 
 
 11. Thefe Experiments we fhall endeavour 
 to make as general as we can, and give an 
 Example in each of the three Kingdoms, as 
 they are called, viz, the Vegetable, Animal, 
 and Mineral 
 
 Expe r I me n t I. 
 
 "fhat Vegetables are refoluhle^ by Fire^ into four of 
 the chemical Principles^ viz. Water, Oil, Salt, 
 and Earth. 
 
 12. We took two Pounds of common Worm- 
 wood cutfmall, which we put into a Glafs Retort 
 in a Sand-Heat, and diftilling with Degrees of 
 Fire, and a frequent Change of Receivers, we ob- 
 tained (i.) an aqueous Liquor, and (2.) an Oil. 
 Then taking out the Remainder, and burning, 
 or calcining it, in the open Air, it turned to a 
 grey Kind of Afhes ; which being boiled in fair 
 Water communicated thereto (3.) a Salt. This 
 Salt we obtained in a dry Form, by letting the 
 Solution ftand at Reft for fome Time, then decant- 
 ing the clear Liquor, and exhaling the fuper- 
 fluous Water. And (4.) we found an earthy 
 Subftance remaining at the Bottom of the Wa- 
 ter wherein the Afhes were boiled, 
 
 13. This Experiment being well attended to 
 is very inftruftive, and fliews that the chemical 
 
 Princi- 
 
Of Analytical Chemijlry. 149 
 
 Principles above-mentioned are not imaginary or 
 fictitious Things ; but Things palpable, and evi- 
 dent to the Senfes. For here we have a Water, 
 
 .an Oil, a Salt, and an Earth, all afforded us by 
 a vegetable Subject. And the Experiment may 
 be made general without much Variation : for all 
 the vegetable Subjects hitherto examined, in this 
 Manner, refolve themfelves into the fame gene- 
 ral Principles, which differ only (i.) in Refped 
 of the Kind of Salt ; that being in fome more 
 volatile, in others more fixed ; in fome acid, in 
 others alkaline; and (2.) in the Nature or parti- 
 cular Properties of the Oil ; which in fome 
 Plants is thinner and more fluid, in others more 
 grofs and^vifeous; But all the Principles 
 
 thus obtained agree to the general Definitions 
 above laid down So that there appears to be 
 no Vegetable in Nature, but what is thus refo- 
 luble into Water, Oil, Salt, and Earth. 
 
 14. To obtain thefe Principles pure, we muft TbeWater 
 (i.) feparate all the Oil that may chance to 
 main fufpended in the Water, This is effeded, 
 in a confiderable Degree, by the Filtre ; which 
 being kept continually filling up, fo as that the 
 lighter Oil may not come in Contact: with the 
 Paper, the aqueous Part is thus tranfmitted to- 
 lerably free from Oil. (2.) But flill there may 
 remain fome fmall Proportion of oily and faline 
 Matter therein } If the faline Matter be acid, the 
 way to deflroy it is, to mix a little Chalk, or 
 any pure and fixed alkaline Salt, with the Li- 
 quor. By this means alfo more of the Oil will 
 be fet free ; fo that being now filtred again, 
 and gently diflilled with a foft Heat, the aqueous 
 Part will rife much purer, and pafs for Water 
 in the Judgment of the Senfes. (3.) the Plant 
 
 
 » Sea. 4—8. 
 
 was 
 
150 
 
 Tfo Oil 
 
 ^urijied. 
 
 7he Salt 
 fiurified. 
 
 Lecture the Eighth. 
 
 was alkaline, and an alkaline Salt abound in the 
 aqueous Liquor, let it be made neutral with one 
 that is acid; and thus again the Water may be 
 feparated pure, by means of the Filtre and Re- 
 diftillation. And this is the Method of mani- 
 fefting CO the Senfes, that the chemical Principle 
 IVatcr is naturally lodged in, and may be fepa- 
 rated from all vegetable Subftances 
 
 15. In order to procure the Sulphur^ or oily 
 Principle, pure, the un6luous Matter, obtained 
 by this general Procefs, may be wafhed from 
 its adhering Salts and grofler Earth in warm 
 Water, barely by fhaking them in a Glafs to- 
 gether, and then feparating the Oil from the 
 Water by means of the common feparating 
 Glafs; where, if the Oil be fpecifically heavier 
 than Water, it finks to the Bottom, and may 
 be fuffer’d to run out firft *, if fpecifically lighter, 
 it floats a-top, and may by the Finger applied 
 to the Bottom of the Glafs, or fome other Con- 
 trivance, be kept behind, when all the Water 
 and feculent Parts are run from it. 
 
 16. To obtain the faline Principle pure ; (i.) 
 if it be of the volatile urinous Kind, the Matter 
 may be diflTolved in Water, and made to pafs 
 the Filtre ; then fet in a gentle Heat to fublime : 
 for it will thus rife and leave the W'ater behind, 
 as being much more volatile than that. (2.) If 
 it be required ftill purer, the befl: Method hi- 
 therto known is, to fublime it from finely pul- 
 verized Chalk ; then to faturate it with a clean 
 Spirit of Sea-Salt, fo as to convert it into a true 
 Sal- Am.moniac ; which being mixed with Salt of 
 Tartar, and again fee to fublime, the volatile 
 Salt will rife highly purified, fo as long to 
 retain its Whitenefs. (3.) But if the faline 
 
 * See LcSl. V. Exp. I. 
 
 Matter 
 
Of Analytical Chemiftry. 15s 
 
 Matter obtained be of the fixed Kind, the 
 Method of purifying it is, to diffolve it in fair 
 cold Water ; fufl'er the Solution to fubfide ; then 
 decant the clear Liquor, and evaporate it in a 
 clean Iron Pan or Glafs Veffel, conflantly flirr- 
 ing it, till it becomes dry and white : (4.) Or 
 to purify it llill farther and render it periedly 
 white, let it be put into a clean Crucible, and 
 expofed for a while amidfl the Flame of burning 
 Charcoal, but without Melting it. 
 
 17. Laftly, to obtain the earthy \nTh Earth 
 
 its Purity, let it be thoroughly calcined, boiled 
 
 in feverai Waters, in order to get out all its Salt; 
 then dry it over a clear Fire, or in the Sun, 
 
 And if thefe feverai Operations be performed 
 in Perfedlion, we then obtain what we pro- 
 perly mean by the chemical Principles of Vege- 
 tables. 
 
 18. And tho’ it be not always neceffary for 
 the Purpofes of Chemiftry, or the common Calls 
 of Life, to bring thefe Principles to the Degree 
 of Purity here mention’d, yet there are many 
 Cafes that abfolutely require them to be fo puri- 
 fied ; otherwife the Operations in which they are 
 employed may eafiiy mifcarry : and this we defire 
 may be noted as one confiderable Reafon of 
 the Failure of particular Experiments and Ope- 
 rations, both in Chemiftry itfelf, and in many of 
 the chemical Arts ; particularly the Art of Glafs, 
 Diftillation, iPc. 
 
 ig. The Ufes of this leading Experiment are Ups ofths 
 numerous ; we fliall touch upon a few of them. 
 
 And firft, we may learn from it that thefe che- 
 mical Principles are found in different Quanti- 
 ties in different Vegetables, or in the fame at 
 different Seafons or Times of Growth. Thus, 
 for inftance, Olives, Almonds, Mace, ipc. con- 
 tain fuch an Over-Proportion of Oil, to the other 
 L 4 Prin- 
 
152 Lecture the Eighth. 
 
 Principles, that it may be copioufly got from 
 them barely by Prdfure. I'he Vine in the 
 Spring affords a larger Proportion of fixed alka- 
 line Salt than at any other Seafon f and the fame 
 holds of the Wood ufually burnt for Pot-afh. 
 And thus we find that the aqueous and falihe 
 Principles prefide in Vegetables in the Spring, 
 but the oily in the Summer and Autumn •, that 
 all young Plants abound more with Water, than 
 fuch as are full grown ^ and that Oil is moil 
 plentifully contained in the oldefl Trees, and 
 thofe of the colder Climates. Whence we are 
 direded to the proper Times, Seafons, and Places 
 for felling the Timber defigned for Pitch, Pot- 
 afh, Fewel, and Charcoal. 
 
 20. By applying this Experiment to different 
 Vegetables it has been found, that Vegetables 
 are naturally diflinguifhable into two grand 
 Tribes, viz, the Acid and the Alkaline ; the 
 firft affording a volatile Acid, and the other a 
 volatile Alkali, upon dry Diflillation. Thus 
 Guaiacum, Cedar, Box, Cinamon, Cloves, Sor- 
 rel, Mint, Baulm, ^c, afford an Acid ; but 
 Garlick, Leeks, Onions, Horfe-radifh, Scurvy- 
 grafs, Muftard, ^c, afford an Alkali ; which, 
 when redfified, is hardly diflinguifhable from 
 that of animal Subftances, fo as nearly to re- 
 femble the Spirit and Salt of Hartfhorn a), 
 
 21. This Experiment alfo fliews us the Me 
 thods of making or procuring Tar, Charcoal, 
 fixed Salt, and elementary Earth, from Vege- 
 tables •, four capital Things in Arts and Trades. 
 Tar is the fcorched Oil of undtuous Wood, forced 
 out by Fire, as the grofs Oil is in the prefent 
 'Ex ferment h). Charcoal is Wood burnt clofe 
 
 a) See Le^. VII. Exp. VI. 
 
 b See alfo II. Exp. III. 
 
 to 
 
of Analytical Chemifry. 
 
 to Blacknefs a) \ Soap, a Mixture of fixed Salt 
 and Oil ; Glafs, a mixture of Earth and fixed 
 Salt and elementary Earth makes all the Tefts 
 and Coppels for refining of Gold and Silver. 
 
 22. j^gain, the prefent Experiment fhews us 
 the Nature of vegetable Fumes, by which, in the 
 Way of animal Curation, Fifh and Flefh are long 
 preferved, free from Putrefadtion or Corruption. 
 For where-ever green Wood, or any acid vege- 
 table Matter is burnt, the acid Particles rife 
 With the Smoke, and in this Form penetrate and 
 lodge in animal Subftances expofed thereto *, 
 fo that this Smoke a6ls upon them in the fame 
 Manner as the Fume of Spirit of Sea-Salt or Ni- 
 tre would do. And whether it be not a nitrous 
 Acid which thus tinges the Hams, Herrings, Cfc. 
 red in drying, we recommend to farther Exami- 
 nation. 
 
 23. Our Experiment alfo confirms what was 
 before obferved that the Force of Fire is not 
 fufficient to reduce a vegetable Subfiance to Afhes 
 without the Help of the Air, and that fo long as 
 the fixed Oil, which caufes the Blacknefs, re- 
 mains in a vegetable Coal, it will afford no fixed 
 Salt by Decodlion in Water c). Whence for mak- 
 ing Pot-afh, and all the fixed Salts, to Advan- 
 tage, .we have this Rule, thoroughly to calcine 
 the Subjedl, fo as to leave no fixed Oil behind. 
 
 24. And hence we are alfo inflrudled in the 
 phyfical Nature of a vegetable Coal,' and fee 
 how it may have fuch confiderable Effedfs upon 
 Metals, in the Way of zFlux\ fince we find it 
 contains a fixed Oil, firmly united to the Matter 
 of a fixed Alkali ; whence, to ufe this Coal as 
 a Flux, is the fame Thing as to ufe a fixed Salt 
 
 a) See alfo Lea. II. III. 
 
 h) Lea. II Exp. IV. 
 
 c) Sec Lea, II. Exp, IV. 
 
 ‘ • in- 
 
 153- 
 
154 - 
 
 'Bone ana> 
 iyfcd. 
 
 V:e Expe- 
 riment ex- 
 tended. 
 
 : Lecture the Eighth. 
 
 intimately united with a fixed Oil, which ope- 
 rates powerfully upon Ores, as we have formerly 
 ihewn And fo\much for the Amlyfis of Ve^ 
 getables. 
 
 II. 
 
 Experiment II. 
 
 That animal Matters are refoluhle^ by Fire^ int& 
 the four chemical Principles^ Water, Oil, Salt, 
 and Earth. 
 
 25. We took four Pounds of animal Bones, 
 that had been well boiled to get out their Mar- 
 row or Fat, and then thoroughly dried again ; 
 and breaking them into fmall Lumps, we put 
 them., dry 'as they were, into an earthen Retort, 
 luted on a Glafs Receiver, and diflilled, wdth 
 Degrees of Fleat, in a naked Fire. There firft 
 came over in Drops an aqueous limpid Liquor, 
 which we referved apart, . by changing the Re- 
 ceiver. Then increafing the Fire there came 
 over white Fumes, a volatile Salt, and a Quan- 
 tity of Oil. The VefTels being fuflered to cool , 
 we found the Bones turned black in the Retort ; 
 but being calcined in a naked Fire, with the 
 AdmifTion of the free Air, they turned to white 
 Afhes. Then boiling thefe white Afhes in 
 Water, we found by Evaporation that they 
 communicated no fixed alkaline Salt thereto. 
 
 26. 'I'his Experiment is general, or fucceeds, 
 with little Variation, in all other animal Sub- 
 je6ls, v/hether they be Flefh, Blood, Serum, 
 Fifh, Birds, Snakes, the Whites of Eggs, Horn, 
 Hair, Hoofs, Silk, or the like *, the principal 
 Difference being only, that thefe Subftances 
 
 * See Lea. I. Exp. III. See alfo hereafter the Letlures 
 isipon Mineralooy and Metallurgy. 
 
 refpedively 
 
of Analytical Chemijlry. 155 
 
 refpecflively contain more or lefs Earth, Water, 
 
 Salt, and Oil. Thus Blood being diftilled in 
 its natural State, or as it is drawn from the Vein 
 of a healthy Perfon, will yield about fevcn-eighchs 
 of its Quantity in Water. And if any animal Sub- 
 je6l be not well purged of its Oil, by boiling in 
 common Water, before it is committed to Di- 
 ftillation, it thence affords a greater Quantity of 
 a burnt empyreumatical Oil, that ftrongly taints 
 and impregnates the volatile Salt and Water, 
 with a naufeous Scent and Tafle ; which are hard 
 to get rid of, even by repeated Redfifications. 
 
 27. The Principles feparated by the p refen t 
 Experiment appear to be, in general, the fame' 
 with thofe before gained from a vegetable Subje6l. 
 
 They may be feparately purified and made ele- 
 mentary, after the fame Methods as we there 
 laid down. And thus, by comparing the Pro- 
 ductions of both Procefies together, we fhall find 
 that we have a Water, an Oil, a Salt, and an 
 Earth in both Cafes. 
 
 28. The two Waters feem fcarce to differ, 
 when reduced to the fame Degree of Purity ; no 
 more do the Oils and the Earths ; but all the 
 Salt in the prefent Cafe is volatile *, the Aflies 
 containing no fixed Salt at all : whence this ap- 
 pears to be the principal chemical Difference 
 betwixt vegetable and animal Subjecfi:s, that the 
 vegetable Kind yield a fixed Salt by Calcination, 
 and the animal Kind, one that is volatile by Di- 
 flillation. But this holds only of the acid Species 
 of Vegetables •, for the alkaline Species yields 
 little or no fixed Salt upon Calcination. So that 
 betwixt the alkaline Tribe of Vegetables, and 
 the whole animal Kingdom, there feems to be 
 little Difference ; either in this, or any other 
 chemical Refped But tho^ fome Difference 
 
 ^ See lea, VII. Ext, VI. 
 
 fhould 
 
156 Lecture the Eighth. 
 
 fhould be found betwixt the animal and vege- 
 table Oils, as there is thought to be in the 
 Making of Soap, and fome other Inftances ; yet 
 the Principles of animal and vegetable Subjefts 
 may be juftly reputed the fame, as both equally 
 agree to our general Definitions of Water, Oil, 
 Salt and Earth a) But when the feveral Prin- 
 ciples of Vegetables and Animals are reduced to 
 the fame Degrees of Purity and Finenefs, there 
 feems, fo far as our Trials have gone, to be no 
 fenfible Difference between them. Thus the 
 pure elementary Earth of Vegetables ferves for 
 the making of Tefts and other Purpofes, as well 
 as the elementary Earth of Animals \ folid Soap 
 is made of vegetable Oils, as well as of animal 
 Fats ; and the volatile Salt of alkaline Vegeta- 
 bles, or even of acid Vegetables when putrified, 
 is not to be diftinguifhed from the volatile Salt 
 of Animals, when both are thoroughly purged 
 and purified. 
 
 ^ 9 * the Labour and Difficulty required, 
 malTrin- to bring thefe Principles to a high Degree of 
 ciples Purity, has proved a chief Caufe of their being 
 purified- thought different ; for we fee that the Oil tena- 
 cioufly adheres to the volatile animal Salt* and 
 thus adds fome Qualities that do not properly 
 belong to that Salt. But if a volatile animal, 
 and a volatile vegetable Salt, be each feparately 
 converted into Sal-Ammoniac, by Means of 
 Spirit of Sea-Salt, no fenfible Difference can be 
 found betwixt them. And thus, if a vegetable 
 Oil and an animal Oil were equally purified, 
 fubtilized, and freed from all the Matters that do 
 not effentially belong to them, they would not 
 fenfibly differ. At leaft, this feems confirmed 
 by feveral Experiments hfi 
 d) See above, §4—8.^ 
 
 h See Dr. Cox% Papers in the Philofcphtcal Tranfadions, 
 
 30. And 
 
of Analytical Chemiftry. 157 
 
 33. And hence may fome Advantages be 
 rived to Arts and Trades, by making the Sub- 
 jed:s of one Kingdom ferve for thofe of the 
 other, where the one is cheaper than the- other. 
 
 Thus, as we before obferved a volatile Spirit 
 and Salt, like thofe of Hartfhorn, may be drawn 
 from the alkaline Species of Vegetables, and all 
 putrefied Plants ; at leaft from Bones, purged 
 of their Fat by boiling in Water. 
 
 31. The prefent Experiment has many other 
 Ufes and among the reft remarkably (hews how 
 a perfectly dry, infipid, fcentlefs, and folid Bo- 
 dy may yield a great Variety of Taftes and 
 Odours, barely by being applied to the Fire. 
 
 For the impure Water, the volatile Spirit, the 
 Salt and the Oils, have each a particular Tafte 
 and Odour. And tho’ the Subjcd itfelf were 
 fixed, we fee it neverthelefs affords feverai vola - 
 tile Matters. And as this fixed Subftance was 
 originally compofed of a fluid Matter, we are 
 hence taught that the animal Solids and Fluids 
 have the fame common Nature ; their Difference 
 confifting only in a greater or lefs Proportion of 
 Water and Earth. For Blood, upon the like 
 Analyfis, affords more Water and lefs Earth 
 than Bone. 
 
 32. This Experiment likewife fhews us that 
 a Bone may be entirely divefted of its Water, 
 
 Salt, and Oil, without lofing its priftine Fi- 
 gure and Dimenfions. For after thofe Principles 
 are feparated from it, the elementary Earth, 
 tho’ abfolutely dry and friable, ftill hangs toge- 
 ther in the natural Form and Figure of the 
 Bone ; which thus remains exhaufted of all that 
 Matter, which the Fire was able to carry off, 
 without affeifting the elementary Earth itfelfi 
 
 * See VI. VI. 
 
 Whence 
 
1^8 LecturetheEighth. 
 
 Whence we evidently fee that the Ufe of this 
 elementary Earth, in vegetable and animal Bo- 
 dies, is to afford a Lodgment, a Support, or 
 Skeleton to the other Principles, which are much 
 more diffipable and deftrublible than itfelf. 
 
 33. And as our Experiment fucceeds alike in 
 all animal Matters, and even in the Jelly ob- 
 tained from a Bone by long Boiling, till the ele- 
 mentary Earth is elixated, or drained of the other 
 Principles *, v>/e hence learn that the Matter of 
 thefe other Principles proceeds only from the 
 Juices of the Body, where, as well as in the 
 Jelly, they appear in an almoft infipid and in- 
 odorous State, yet are capable, by Diftillation, of 
 affording Subftances fo highly fapid and odorous, 
 as we find the volatile Salt and Oil to be. 
 Whence this Conclufion naturally follows, that 
 thefe Iffinciples did not exift in a volatile State 
 in the Body, as requiring even a greater Degree 
 of Heat, than that of boiling Water, to fepa- 
 rate them. 
 
 34. We may farther obferve that the prefent 
 Experiment affords us the moft volati'e Sub- 
 -ilance hitherto known ; for well-purified animal 
 Salt is more volatile than Spirit of Wine, and 
 rifes in Diftillation before it. Hence this Salt 
 readily evaporates in the open Air, and being 
 laid upon the Palm of the Hand goes off infen- 
 fibly, without any Effedt *, tho’ if it were preffed 
 clofe to the Skin, by a (licking Plaifter, it would 
 prove corrofive •, and in this Manner it is fome- 
 times ufed, (or making Iffues in Children, inftead 
 of the ftronger Caufticks. 
 
 III. Ex- 
 
of Analytical Chemiflry. 159 
 
 III. 
 
 Experiment III. 
 
 ^hat certain mineral or metallic Bodies may contain 
 four of the chemical Principles^ viz. Sulphur, 
 
 Salt, Earth, and Mercury. 
 
 35. We took two Ounces of native Cinnabar Cinnahar 
 reduced to fine Powder, and mixing it with fix anahfed. 
 Ounces of Quick- lime, we put the whole into an 
 eathern Retort, and diftilling into a Bafon of 
 Water, we found a confiderable Quantity of 
 running Mercury at the Bottom thereof The 
 Matter remaining behind in the Retort being 
 boiled in a Lixivium of Pot-afh, and the Solu- 
 tion precipitated with Allum, lets fall a fine Kind 
 
 of Brimftone called Lac Sulphuric^ which will 
 fublime into true Flowers of Brimftone, that 
 may be melted, and run into a Roll. This Brim- 
 ftone being burnt, in the common Method, un- 
 der a Glafs Bell, refolves into an acid Liquor, 
 leaving an uninflammable, fcurfy, terreftrial Mat- 
 ter behind ; which being treated as an Ore, fome- 
 times affords a fmall Proportion of Metal, either 
 Iron or Copper. 
 
 36. We have here an inflrudlive Experiment, 
 which being fully explained might lead to con- 
 fiderable Difcoveries. It fhews that a true run- 
 ning Mercury may lie concealed in metallic Ores, 
 or ftony Earths ; for native Cinnabar is but an 
 Ore of Mercury, confifting, as we fee, of two 
 different Matters, Sulphur and Quickfilver, which 
 
 * We endeavoured to feparate the Sulphur from the Cin- 
 nabar, by boiling fome pulverized Cinnabar in a ftrong lJxi~ 
 tvium of Pot afh and Quick-lime, expefting the Mercury 
 Ihould fall to the Bottom in a running Form j but had no 
 Succefs at the End of two or three Hours. 
 
 filver i 
 
i6o 
 
 The ExU‘ 
 
 riment 
 ^jhet> €>' 
 extendible 
 
 Lecture the Eighth. 
 
 filver, which are feparable by Diftillation with 
 Qiiick-lime or Iron Filings ; and fomerimes by- 
 long Boiling in a ftrong alkaline Lixivium, 
 
 37. It were highly proper, if poflible, to ren- 
 
 der the prefent Experiment general •, and, if the 
 Nature of the Thing would admit thereof, apply 
 it to extract a running Mercury from Metals, as 
 we have here done from a native Ore or mineral 
 Subftance. For the more intelligent Chemifts 
 agree, that the true Analylis of metalline Mine- 
 rals depends upon what is called their Mercuriji- 
 cation\ that is, the obtaining Mercury from 
 them. And for this Purpofe there are three 
 
 Methods propofed. The firft is by Means of a cer- 
 tain Mercury, fo prepared as to have a dilTolving 
 Power, and to take up the Mercuries of Metals, 
 in the fame Manner as Water diffolves Salt from 
 Afhes. The fecond is by Means of certain re- 
 generating Salts, particularly Sal- Ammoniac which 
 fliall detain the more earthy Parts of Metals, and 
 leave their Mercuries feparable ffom them by 
 Sublimation or otherwiie. And the third Me- 
 thod is by Means of a large Zm, or double 
 Convex Glafs *, in the Focus whereof, if any 
 Metal be applied, its mercurial Part is faid to 
 feparate and go off in Fume, which when col- 
 leded and condenfed appears to be running 
 Mercury. 
 
 38. The firft Method would be eafy, if the 
 proper Mercury for the Purpofe could be readily 
 procured. The fecond is extremely laborious, 
 and requires much Patience, and Reiteration. 
 But the third feems eafy enough, and pradticable 
 to Advantage, when a Glafs of three or four Foot 
 in Diameter is at hand, the Sky ferene, and the 
 Sun ftiines ftrong 
 
 * See M. B.omherg\ E^eperiments, with the Duke of Or- 
 hanii Lens, in the French Msfnoirs, 
 
 S 9 - Let 
 
of Analytical Chemijlry. i6i 
 
 39. Let us not be mifapprehended as if we were 
 here launching out beyond the Conhnes of ge- 
 nuine Chemiftry, whofe Ofiice it is to keep clofe 
 to the Senfes, without indulging any Degree of 
 Speculation and Hypothecs : we only mean to 
 give an Occafion for proper Trials to be made, 
 which alone can determine whether running Mer- 
 curies are obtainable from Metals, or whether a 
 fixed Metal may not be obtained from running 
 Mercury. Indeed we fhould be wanting to the 
 Art we are endeavouring to improve, if we 
 did not, at a time when almoft; every Chemift in 
 England is preparing the Mercurius pr^ecipitatus 
 per fe^ requeft them to try whether a fmall Por- 
 tion of their fluid Mercury is not by the Opera- 
 tion fixed into a folid Grain of Metal ; and if fo, 
 what Metal it is, and whether more of it be not 
 procurable by grinding their Precipitate, ex- 
 pofing it again to Digeflion, and repeating this 
 Operation for a Number of Times fuccelTively, 
 till it may happen that Part of it will bear 
 the Cupel. 
 
 40. In the fame View we recommend it, to 
 thofe who defire the Improvement of Chemiftry, 
 that they would procure a double Convex- Glafs, 
 three or four Feet in Diameter, and try whether, 
 when a Metal is expofed to the hocus thereof, 
 the metallic Matter- which goes oft in Fumes, 
 being colledled by a proper VefTel dextroufty ap- 
 plied and plunged in cold Water, may not be 
 thus condenfed, and afTume the running Form 
 and other Properties of an actual Quickfilver. 
 
 If thefe Experiments fucceed, they may richly 
 repay the Coft, by ufeful Knowledge at leaft. 
 
 4 I. 'But to proceed ; Vv^e are farther to obferve 
 from the foregoing Experiment, that as common 
 Brimftone refolves itfelf into an acid Liquor and 
 an earthy Matter, v/e find that certain mineral 
 
 M or 
 
1 62 
 
 Lecture the Eighth. 
 
 or metallic Subfiances will, by a proper Analyfis, 
 afford the four chemical Principles above men- 
 tioned *, viz running Mercury, Sulphur, Salt, 
 and Earth. But it is not fuppofed to hold uni- 
 verfally, that all mineral Subftances fliould afford 
 a running Mercury upon their Analyfis ; but on- 
 ly fuch of them as are properly metallic. 
 
 ^efult of Analyfis of Minerals has 
 
 the Analy^ been Carried, it fhould feem that all Metals con- 
 fis of Mi- tain a running Mercury, fixed in them, as Water 
 nerals, jg fixed in dry animal or vegetable Subfiances ^), 
 and joined with a Sulphur, or an inflammable 
 Part, and an Earth ; befides a little Salt in fome 
 of them h). The Folfil Salts refolve into a large 
 Quantity of Acid, which is always united with 
 fome Sulphur, and a fmall Proportion of Earth. 
 Mofl Stones refolve into a large Proportion of 
 Earth, and a fmall Quantity of aqueous and ful- 
 phureous Vapour. And Earths refolve into a 
 mere terreflrial Subftance, a little aqueous Acid, 
 and a fmall Proportion of Sulphur. 
 
 43. Upon the whole therefore we may conclude, 
 that the five Principles above laid down, viz. 
 Water, Earth, Salt, Sulphur, and perhaps Mer' 
 cury, are the true Chemical Principles of vege- 
 table, animal and mineral Subfiances r). 
 
 Axioms Canons. 
 
 ♦ 
 
 I. It appears from our preceding Enquiry, 
 That genuine Chemifhry confifls in a legitimate 
 Ufe of the Senfes, keeping entirely to fenfible 
 
 fl) See LeS. III. ad finem, 
 
 b) See M. Homberg upon the Chemical Principle?, in the 
 Trench Memoirs. 
 
 c) No notice is here taken of Air as a Chemical Principle, 
 for the Reafon before alTigned. See above, § 3. See alfo 
 Le<^. UI. faJItm. 
 
 Things 
 
Of Analytical Chetnlfiry. 163 
 
 Things, or the Law of Indudlion, for its Prin- 
 ciples and Explanations a) \ but, if it once in- 
 dulges hypothetical Notions, Fidtion, Iliufion, and 
 Darknefs enfue, inftead of fure Rules, ufeful 
 Difcov^eries, and Light to the Underftanding. 
 
 2. That the common chemical Principles are 
 juftly faid to be Water, Earth, Salt, Sulphur, and 
 Mercury •, whereby many chemical Effecfls are 
 explicable to common Senfe and Reafon, fo far 
 as to afford Rules of working, to the Advantage 
 of the Art and of ordinary Life b), 
 
 3. That as animal and vegetable Subfiances 
 are refolvable into the fame Principles there is 
 no NecelTity for making more than two Diflinc- 
 tions or Claffes of chemical Principles, n^iz. the 
 Vegetable and Mineral ; which feem to differ 
 chiefly in this, that the metallic Species of Mine- 
 rals may afford a running Mercury, whereas the 
 vegetable and Ample mineral Species will not. 
 
 4. That the different Combinations of thefe 
 Ave chemical Principles make all that vafl Variety 
 of natural and artiAcal Bodies, which have hitherto 
 been analyfed by the Fire ; the Difference of thefe. 
 
 Bodies appearing to arife from, the different Pro- 
 portions wherein thefe Principles are mixed. 
 Whence, unlefs we except the Air, there feems 
 no Neceflity for introducing a larger Number of 
 Principles, to account chemically for all the va- 
 rious Phasnomenaof Nature and Art. 
 
 5. That the correfpondent animal and vegetable 
 Principles may in many Cafes be ufed for one an- 
 other \ fo as to render volatile Salts and Oils 
 cheaper, and leffen the Expence attending their 
 Ufe in particular Arts and Trades h]. 
 
 a] See the who^c LecTture, fojjlm, 
 
 h) See I. II. 
 
 M 2 
 
 6 . That 
 
164. Lecture the Eighth. 
 
 6. That in order to leffen the Trouble and Ex- 
 pence of procuring the volatile Salts of animal 
 Subjects, thefe Subjects hiould be firfl purged of 
 their Oil and undluous Parts by boiling in Wa- 
 ter : after which they may be made to afford vo- 
 latile Salts and Spirits, as pure as unboiled Plart- 
 Ihorn, or purer a). But care muft be taken not 
 to boil the Subjedl too long, otherwife a Jelly 
 will alfo be drawn out of it; which Jelly plenti- 
 fully contains the Matter of the volatile Salt. 
 
 7. That the unreflified volatile Salts of vege- 
 table and animal Subftances are true Sales volatiles 
 cleoft\ that according to the Difference of the Oil 
 abounding in them, they are properly d iff ingu idl- 
 ed into Sait ol Hartfhorn, Salt of Ox bone. Salt 
 of human Blood, of Silk But that when thefe 
 Oils are totally feparated from them, they be- 
 come one and the fame undiftinguifhable vola- 
 tile Salt }?), 
 
 8. That the fo called volatile Spirits of vege- 
 table and animal Subffances, confifl only of a 
 large Proportion of Water, impregnated with fome 
 of the volatile Oil and Salt of theSubjedls; and 
 that they may accordingly be refolved by Redtifi- 
 cation into thefe three Principles ; fo that there 
 is no Neceffity for introducing a fpirituous Prin- 
 ciple h), 
 
 9. That it is the Admixture of Oil which gives 
 the Colour to volatile Salts and volatile Spirits ; 
 for when this Oil is totally feparated from them, 
 the Salt is permanently white, and the Spirit 
 pellucid c), 
 
 a) SesExp.il. 
 
 U) See Exp. I, II. 
 
 f) See Exp. II. 
 
 JO. That 
 
Of Analytical Chemiflry. 165 
 
 10. That volatile Salts are obtainable from ail 
 Kinds of Land Animals, the amphibious and 
 fubterraneous Tribes, Birds, Fifn, and Reptiles; 
 from alkaline Vegetables without Putrefadion ; 
 from other Vegetables after Putrefadion ; from 
 Soot, Horns, Hoofs, and all refufe animal and 
 vegetable Matters, fuch as the Pith of Horns, 
 
 Urine, the Blood of Slaughter-houfes, dfr. and 
 that as pure and perfed as from Hartfhorn : 
 
 Which alfords a Rule for making volatile Al- 
 kalies and Sal-Ammoniac cheap in England, 
 
 1 1. That elementary Earth, a Subftance fixed 
 and ofitfelf unalterable in the Fire, Air, or Wa- 
 ter, conftitutes the firm Bafis, or Skeleton, of all 
 animal and vegetable, Subftances ; and that Wa- 
 ter, Salt, and Oil mixed, and wedged betwixt the 
 Particles of this Earth, confiitute all animal and 
 vegetable Subftances a). 
 
 12. That there is only one Kind of volatile 
 alkaline Salt, when reduced to abfolute Purity, 
 the apparent Difference betwixt the volatile Salts 
 depending entirely upon the different Oils where- 
 with they are mixed h), 
 
 13. d'hat by endeavouring to purify the che- 
 mical Principles too high, we do but deftroy 
 their Natures r), or lofe the Properties whereby 
 they produce their fpecific Effeds. Thus Oils are, 
 by numerous repeated Diftillations, loft in the 
 form of Oils, and turned into Earths ; volatile 
 Salts fly away in repeated Sublimation ; and 
 fixed Salts turn to Earth by repeated Solution 
 and Filtration d), 
 
 14. That animal Bodies naturally contain no 
 fixed Salt, tho’ the acid Vegetables, which are 
 
 a) See Exp, I, II. \ 
 
 See Exp. I, II. See alfo hereafter the Ledlure upon Oils. 
 
 r) See Exp. 1, II. 
 
 4) See Mr, Boyk\ Sceptical Chemiji, 
 
 M 3 
 
 ufed 
 
1 66 
 
 Lecture the Eighth. 
 
 ufed as Food, contain it plentifully a). Whence 
 there is lodged in the Body a Power of convert- 
 ing the Matter of fixed Salt into the Matter of 
 volatile Salt. 
 
 15. That the volatile animal Salts, and the fixed 
 vegetable Salts, differ chiefly with regard to their 
 Volatility and Fixednefs, and the Effe6ts thereon 
 depending ; but agree in other Refpedls. Thus 
 they both make an Efiervefcence, and turn 
 neutral, when faturated with Acids j they are 
 both corrofive, hot and fiery, a), 
 
 16. That a principal Reafon of the Difficulties 
 attending the Analyfis of Bodies, is the natural 
 Affinity, or Relation, which fome of the chemi- 
 cal Principles have to others ; whence they cohere 
 Itrongly together, fo as not to be well feparated 
 pure ^). Thus part of the volatile Oil of Animals 
 ufually rifes with the fame degree of Heat as 
 the volatile Salt, and intimately mixes there- 
 with, ^c: Whence, to improve Chemiftry, we 
 ffioLild feek out for other analyfing Powers be- 
 fides Fire. And fuch an one in the prefen t Cafe 
 is Water *, which imbibing the volatile Salt, 
 more flrongly than it does the Oil, thus makes a 
 more perfect Separation ; whereas Fire chiefly 
 a6ls as an Analyfer, when there is a confiderable 
 Difference between the Volatility of Bodies ; as 
 in a Mixture of Water, Alcohol, and volatile Salt, 
 all which rife feparately after one another ; the 
 volatile Salt firfl, the Alcohol next, and the Wa- 
 ter lafl. 
 
 17. That the Mercuries of Metals may be 
 real things, and procurable different Ways; and 
 that poffibly thefe Mercuries, or the common 
 running Mercury, may be convertible into Me- 
 zz J See Exp. T, IT. 
 
 See Exp. 1,11,111, 
 
 cal 
 
Of Analytical Chemiflry. 167 
 
 tal. But this Matter requires a farther Exami- 
 nation, and fhoLild be brought under the diredt 
 Evidence of Senfe a ). 
 
 18. Laflly, that there are certain Inftruments 
 and chemical Operations, which though little 
 attended to may afford great Light to the Un- 
 derftanding, and prove highly advantageous in 
 chemical Fhilofophy and Arts : we inflance, for 
 the prefent, the Mercurification of Metals, the 
 powerful Furnace of the Sun, the artificial Ufe 
 of the common Elements, a) all which we 
 recommend to the farther confideration of che- 
 mical Fhilofophers. 
 
 a) See III. 
 
 M 4 
 
 L E C- 
 
[ «68 ] 
 
 7ke Sub- 
 joa. 
 
 LECTURE IX. 
 
 CONTAINING 
 
 Synthetical Chemiftry; c?\ the Art of lie - 
 compojing Bodies. 
 
 I. 'T N our laft Leftiire we endeavoured to ex- 
 ^ plain what the more intdligcnt Chcmifls 
 underftand by analytical Chemijiry., or the Reio- 
 lution of Bodies ; in the prefent we propofe to 
 give fonie Inftances of Recompofition, or the 
 compounding of Bodies from their feparated 
 Parts or Principles, fo as to compofe the Ori- 
 ginal whole again. This indeed is exiremely 
 difficult to effedf univerfally *, yet it may be done 
 in fome cafes fo accurately, that the recornpofed 
 Body fhall be perfedfly undillinguiffiable, by the 
 Senfes, from that which had never been Icparated 
 by the hire. And if the Art of Chemiitry were 
 perfedl it would be able thus to recompofe, at 
 leaft in fome tolerable manner, all the Bodies it 
 divides. At prefent it is far from this Perfection, 
 efpecially in the vegetable and animal King- 
 doms-, where, by re alb n of the vafcular I'exture 
 of the Parts, fuch a Recompofition feems almofl: 
 impracticable, unlefs the natural or organical 
 Structure be fome way or other preferved, or 
 artificially imitated. We are therefore carefully 
 to dillinguifli betwixt the Regeneration of orga- 
 nized, and the Regeneration of unorganized 
 Bodies. As the latter is much the more fimple 
 and eafy, we ffiall begin with that, and afeend 
 by degrees to the more complex Kinds fo as to 
 
 fiievv 
 
Of Synthetical Chemifiry: i6g 
 
 fliev/ where this Regeneration may be rationally 
 expeded, and where it is lefs to be hoped for ; 
 together with the ways of carrying this Fart of 
 Chemiftry to greater Perfection. 
 
 '2. This Synlhetical Chemiftry^ taken in i\\q Syfjtbefical 
 ftriCl Senfe, for the Recompofition of Bodies Chen:ipry\ 
 from their own Principles, is rather of phiiofo- 
 phical than ordinary Ufe. And it will doubtiefs 
 be alked, to what Purpofe do we ftudioufly en- 
 deavour to recover thofe Bodies by Art, which 
 Nature affords us in plenty ? We anfwer, it 
 would fhew an extreme Perfection and Power in 
 Chemiftry to be able to do this, and prove, 
 either that Bodies might be taken to pieces by 
 the Fire, without altejing or injuring their natu- 
 ral Parts, or at leaft that any accidental Altera- 
 tion brought upon them by the Analyfis, might 
 eafily be reCfihed or aboliftred by a Recompo- 
 fition. 
 
 But here we are to guard again ft a Fallacy : 
 for fuppofing the Art of Chemiftry fo far ad- 
 vanced as to reinftate Bodies after their Ana- 
 lyfis, we muft not thence conclude that Nature 
 originally ufes the fame Means to compofe them. 
 
 The Ways fhe ufes for this Purpofe would ftill 
 be a new Enquiry, and ought to be diligently 
 profecuted, for the farther Improvement of Phi- 
 lofophical Chemi(try. 
 
 4. Our firft Example of Recompofition is 
 taken from Nitre, the fecond from Brandy, the 
 third from Cinnabar, and the laft from Bone. 
 
 Experiment I. 
 
 Phe Regeneration^ or Recompofition of Nitre ^ from 
 its own acid Spirit and fixed Alkali. 
 
 5. We took two Pounds of refined Sak-Petre 
 reduced to Powder, and putting it into a Glafs- redulerto 
 
 Retorts 5 /zV/V. 
 
lyo Lecture the Ninth. 
 
 Retort poured upon it a third of its own 
 Weight of redlified Oil of Vitriol; then placing 
 the Retort in a Sand-heat, and' luting on a large 
 Receiver, we diftilled with degrees of Fire, up » 
 to the higheft that Sand would give. Then fuf- 
 fering all to cool, we thus obtained a pure and 
 ftrong Spirit of Nitre ; which came over in red 
 Fumes, and cannot, by any Experiment, be 
 found to participate of the Oil of Vitriol ufed 
 in its Preparation. 
 
 And a fix- 6. On the other hand, we took a Pound of 
 ed Salt, purified Nitre reduced to Powder, and melt- 
 ing it in an earthen Crucible, caft little pieces 
 of Charcoal into it fucceffively, till the Defla- 
 gration ceafed, and the Salt at the Bottom of 
 the Crucible appeared fiuggifh, or would no 
 longer keep fluid, with that Degree of Heat 
 which melted it before. Then increafing the Fire, 
 fo as to make the Salt run again, we poured it 
 out upon a clean metalline Plate, where it con- 
 geal’d into a Subftance called fixed Nitre. 
 
 7. And thus, at two different Operations, we 
 refolved the fame Subjecfl, Nitre, into two very 
 different Parts ; which being put together again, 
 after a proper Manner, conflitute the original 
 Salt again, in all its Forms. 
 
 Recom- 8. For if the alkaline Solution of fixed Nitre 
 pfed. in Water, be exactly fatu rated with the acid 
 Spirit of Nitre, till no more Effervefcence ap- 
 pears, and yet the Mixture be not made alka- 
 line ; this compound Liquor will, by ftanding, 
 fhoot into true and perfedl Cryflals of Nitre, as 
 we found upon Trial. And the Experiment 
 fucceeds no lefs, if any other fixed alkaline Salt, 
 as that of Tartar, Pot-afli, be ufed inftead 
 of fixed Nitre. 
 
 9. And in the fame manner may common 
 Salt be regenerated from any fixed alkaline Salt, 
 
 and- 
 
Of Synthetical Che?nijlry. 171 
 
 and the acid Spirit of Sea-Salt ; or Alum, from 
 any fixed alkaline Salt and Spirit of Alum; fo 
 as to afford us Inflances of the juftefl Recom- 
 pofition perhaps hitherto known in Chemiflry, 
 
 10. It is remarkable in this Experiment, that V/es, 
 the two Subllances which compofe the Nitre are 
 extremely different; the one being highly odo- 
 rous and volatile, the other inodorous and fixed ; 
 
 the one a violent Acid, the other a violent Al- 
 kali ; but upon mixing, they unite into a neutral 
 Sait, of the very fame Nature and Properties with 
 that which afforded them. 
 
 11. From this Experiment fome have ventured 
 to affirm that Nitre is naturally generated in the 
 fame manner ; but this fhould not be allowed 
 till it is fhewn that fuch an Acid and fuch an Al- 
 kali are to be found diftindl in the places where 
 Nitre grows. And we cannot too well remem- 
 ber, that there may be feveral phyfical Ways of 
 effecting the fame Thing; all which Ways are 
 not to be prefumed, but fought. 
 
 12. To this Clafs of artificial Recompofitions 
 may be added the Reprodudlion of Sulphurs and 
 Vitriols ; tho’ the Experiments do not commonly 
 fucceed in Perfedtion. Indeed, as we above ob- 
 ferved that the Thing itfelf is chiefly of philofo- 
 phical Ufc, for that Reafon very few have endea- 
 voured to profecute it. 
 
 13. In our prefent Experiment we may ob- 
 
 ferve that the Nitre, tho’ in both Cafes it fuffers 
 a great Violence of Fire, is neither fcorched nor 
 rendered empyreumatical ; which in other Cafes, 
 where the Subject is more oily, feems a principal 
 Caufe of the Difficulties found in the regeneration 
 of Bodies; particularly fuch as Sugar, Turpen- 
 tine, Amber, Whence we are directed to 
 
 analyfc thefe undtuous Bodies, with fuch a degree 
 of Heat as fhall hot fcorch their Oil, if we de- 
 
 firc 
 
172 
 
 Br^andy 
 
 analyjed. 
 
 Lecture the Ninth. 
 
 fire to recompofe them ; or elfe to find out 
 fome more proper Analyfer for them than the 
 Fire ; fuch as particular Solvents, capable of fe- 
 parating, and others of reuniting their compo- 
 nent Parts, without having this defi:ru(fi:ive Effedl. 
 
 14. The Solvents here intimated might have 
 confiderable Ufes, it a competent Set of them 
 were difcovered, as diredlly tending to the Im- 
 provement both ot analytical and fynthetical Che- 
 miflry. Thus Water in fome Cafes is a better 
 Analyfer than Fire, as we fee particularly in 
 the feparating of Salts from Earths ; and thus 
 fome Chemifts are faid to have a Method of re- 
 covering analyfed Amber, or Amber diftilled for 
 its Salt and Oil ; and that by means, not of the 
 Fire, but of an artificial compound Salt ; the In- 
 fiances of which Kind fhould be colledted. 
 
 Experiment IL 
 
 Brandy refolded into its component Parts^ and 
 recompofed, 
 
 15. (i.) To a Pint of Brandy we added half 
 a Pound of dry Salt of Tartar, then fet the con- 
 taining Glafs in a gentle FIcat of Sand ; where 
 we obferved the Salt to difiblve into a Liquor, 
 by attracting to itfelf the Water of the Brandy, 
 leaving a Spirit of Wine floating on the top. 
 This Spirit we decanted upon a little more dry 
 Salt of Tartar, and found that this fecond Salt 
 fcarce relented. Then pouring the Spirit into a 
 Glafs Receiver, we diftilled it gently over, and 
 thus obtained a highly rectified Spirit of Wine. 
 (2.) In the fame manner we diftilled the faline So- 
 lution left behind upon decanting the Spirit, and 
 thus obtained the Water of the Brandy in confi- 
 derable Purify, leaving the Salt of Tartar behind, 
 
 in 
 
Of Synthetical Chemijlry. 173 
 
 m a dry Form. (3.) In the lafl: Place, we mix- Andre- 
 ed the Spirit and the W ater together, and di-* 
 re<S:ly found the Brandy recompofed, without 
 any confiderable Alteration. 
 
 16. The Separation and Recompofition is how- 
 ever lefs exadt in the prefent, than in the pre- 
 ceding Cafe ; becaufe fome fmall Part of the Sale 
 will always come over in Diftillation, both with 
 the Spirit and with the Water : but when the Ex- 
 periment is performed in Perfe6lion, it may pafs 
 for a tolerably exadl Recompofition. 
 
 17. To this Clafs may be added the Recom- "The Expe- 
 pofition of Wine, after its Spirit or Brandy has 
 
 been diftilled from it, and the Recompofition of ' 
 Vinegar from its Spirit and Rejiduum, Though 
 both require a new Fret, or flight Fermentation. 
 
 Yet if the Operation be dextroufly performed, 
 the Recompofition appears to be juft and perfedl. 
 
 To render the Operation perfedf in either Cafe, 
 we recommend the Ufe of a proper intermediate 
 Subftance, either fermentable, or adlually in a 
 fermenting State ; fuch as a little new Wine, 
 
 Sugar, Juice of the Grape, or the like: for 
 thefe Subftances coming to work in the Liquor, 
 lay hold both of their aqueous, fpirituous, and 
 faiine Parts ; fo as to bring them into the State 
 of Mixture or Arrangement, on which their Per- 
 fection, as Wines and Vinegars, depends. And 
 how far this Method of Recompofition may be 
 extended feems hitherto little confidered. 
 
 18. In our prefent Experiment for the Recom- 
 poution of Brandy, there are only two confti- 
 tuent Parts concerned, viz. Alcohol and Phlegm ; 
 which renders the Separation and Combination 
 fo much the eafier and the more exa6t : nor is 
 there any Occafion here for an intermediate Sub- 
 ftance, to procure, or recover, the natural Union *, 
 becauie Alcohol readily mixes with Water, barely 
 
 by 
 
174 
 
 Lecture the Ninth. 
 
 by Ibaking, and that as intimately as is necelTary 
 to the Conilitution of Brandy. 
 
 19. In Imitation ot this Experiment, it is pro- 
 per to enquire v/hat other Bodies may be perfectly 
 leparated into different Parts by the Way of 
 Menftruum, Abforbenr, or Precipitant ; fo as 
 to leave the feparated Matters unaltered in their 
 Natures, and tit to compofe the original Sub- 
 fiance again. This Enquiry depends upon find- 
 ing out the fecret Relations which exifb between 
 particular Bodies j and thefe Relations can only 
 be difeovered by particular Trials a). 
 
 Farther 20. This Experiment fliews an ufeful Method 
 of obtaining Spirit of Wine from Brandy, with- 
 out Diffiliation, which may be pradcifed to advan- 
 tage in the large Way of Bufinefs ; viz. by adding 
 Pot-afli to the Brandy once diftilled, and brought 
 to the Size commonly called three Fifths^ that is, 
 three Parts Alcohol and two of Water : For the 
 Pot-afli fo employed is eafily recoverable without 
 much lofs, barely by boiling the Lixivium in an 
 Iron Pot •, by which Means being dried it wdll 
 ferve for the fame Purpofe again. This flight 
 Experiment has proved of eminent Service, where 
 large Parcels of Brandies have been to be reclifled 
 in a fmall Compafs of Time. 
 
 Experiment III. 
 
 Cinnabar recompofed^ by the Union of its two com- 
 ponent Parts^ Sulphur and Mercury. 
 
 Cinnabar 21. Having found, in our lafl Lecture, that 
 native Cinnabar is compofed of Sulphur and Mer^ 
 cury b)^ we took four Ounces of common Brim- 
 
 a) See M. Geoffrofs Paper to this Purpofe in the French 
 ^iemoirs^ 
 
 b) See Lea. VIII. Exf. III. 
 
 flone, 
 
Of Synthetical Chemiftry. 175 
 
 ftone, and melting it in a earthen Pan, over a 
 dull Fire, added by Degrees twelve Ounces of 
 crude Quickfilver, firft made warm, and ftirred 
 them well together, till no Globules of the Quick- 
 filver appeared •, then fuffering the Mafs to cool, 
 we reduced it to Powder, and fublimed it, with 
 a' proper Degree of Heat ; and thus obtained an 
 artificial Cinnabar, which being ground fine, and 
 compared with the natural, appeared undifiin- 
 guifhable from it. 
 
 22. The regenerated or artificial Cinnabar has 
 not the fliony Form of the native ; this Form 
 being accidental in the Mine, and determined 
 by the Circumftanccs of the Place, as the Form 
 of the regenerated Cinnabar is by the Figure and 
 Make of the VefTel wherein it was fublimed. 
 
 But if the two be compared together, in all other 
 Refpeds there appears no Difference, when the 
 Operation is juftly performed. 
 
 23. This Experiment fhews us the common 
 Method of preparing artificial Cinnabar, which 
 may, in the large Way of Bufinefs, be thus 
 fublimed in a tall earthen, or coated Body, with 
 its Head well luted on, and fo placed in a Sand- 
 Heat as to touch the Bottom of the Iron-Pot, 
 whilft the Sand rifes above the Matter contained 
 in the VefTel. And here it is a principal Caution 
 to life a briflc Fire, that the Operation mi ay be 
 finifhed in three or four Hours Time. And pro- 
 bably, if only one Part of Sulphur be ufed to 
 about four Parts of Quickfilver, the Cinnabar 
 wdll be the finer •, for about thirteen Ounces of 
 running Mercury may be recovered from a Pound 
 of native Cinnabar. 
 
 24. And thus we have an Inflance of a perfed; 
 Recompofition, in a metallic Body, or Subjedt 
 of the mineral Kingdom : for the Experiment 
 fucceeds alike, v/hen the Sulphur and Mercury 
 
 of 
 
176 Lecture the Ninth. 
 
 of native Cinnabar is ufed a). To this Clafs 
 might be referred the Redu6lion, or Recovery, 
 of all the Calces of Metals to a metallic Form 
 again, by the Addition of any inflammable Mat- 
 ter, which they lofe in their Calcination ; as alfo 
 the Regeneration of Antimony, by melting its 
 Rcgulus with Sulphur •, the Regeneration of Ores, 
 by melting their Metals with Sulphur, fcony Earths, 
 Cfr. fo as to mix them again; and all other InFances 
 of this Kind. 
 
 25. The prefent Experiment is of confiderable 
 ' life, particularly in natural Philofophy, and Me- 
 tallurgy ; as it fhews us that a very large Pro- 
 portion of fluid Mercury may, by Means of a 
 very fmall one of Sulphur, be fixed into a Body 
 of a fliony Hardnefs, fuch as the native Cinna- 
 bar. Whence v/e fliould not be over-hafliy to 
 conclude that Mercury cannot aflTume a metalline 
 Form a). Some metallurgical Chemifts con- 
 tend, that Mercury is nothing elfe but a Metal, 
 overdofed with that Part which gives dudility 
 and foftnefs, which rem arkably belong to all the 
 Metals when amalgamated with Mercury. In 
 fhort, whoever duly lays together all the Pro- 
 perties of Mercury, may perhaps find Caufe to 
 allow it a metallic Nature 
 
 Experiment IV. 
 
 Attempt to recompofe Bene from its AJhes. 
 
 Bone re^ (^0 took a large Ox-Bone, and made 
 
 comfojsd. a ftrong Jelly thereof with Water in the Di- 
 geftor c)\ then (2.) in an open Fire we burnt and 
 calcined the Bone to whitenefs, without deftroying 
 
 a) See LeSi. VilL Exp, III. 
 h) See the Place laft quoted. 
 c) See Letf, VI. Exp, VII. 
 
 its 
 
Of Synthetical Chemifry. 177 
 
 its^ external Figure; fo that iin other refpccls the 
 Bone was reduced to mere Afhes, or leparaced 
 from the Principles of Water, Oil, and Salt, 
 which it originally contained. In this ftatc we 
 found it extremely brittle and crumbly ; but (^.) 
 putting it into the Digeftor again with the Geliy, 
 and warming them together over the Fire for 
 fome time, then taking the Bone out, and fuf- 
 fering it to dry in the open Air, we found that 
 it gradually hardened, and recovered, in fome to- 
 lerable Degree, the Appearance, or Colour and 
 Confiftence, of the natural Bone. 
 
 27. Geliy, by an Analyfis, is found to yield 
 the fame Principles as Bone itfelf a) \ or to contain 
 the matter, not on'y of Water, but of Salt and 
 Oil, and a little Earth : fo that toufe this Geliy, 
 is the fame thing as to ufe the Water, Salt and 
 Oil; all which being thus together foaked into 
 the Skeleton of the Bone, reftores it in fome 
 Degree to its natural State. 
 
 28. But to ufe the direct volatile Salt and 
 Oil of the Bone for this Purpofe, were to ufe 
 two things which did not exift in thofe Forms in 
 the Bone ; for to feparate the volatile Salt and 
 Oil from Bone, requires a much greater Degree 
 of Heat than that natural to an animal Body ; 
 fo that they are never thus feparated in the Body, 
 whilfl: that remains in its natural State. Yet a 
 Degree of Hardnefs (with Difcoloration, on ac- 
 count of the black and fcorched Oil of the Sub- 
 jed) may be given to Bone-Afhes by the feparated 
 Oil, or even by Water, as we fee in Tells. 
 
 29. We were farther encouraged to ufe the 
 Geliy of the Bone in this Experiment, from ob- 
 ferving by repeated Operations in the Digeftor ^), 
 that all the adlive Principles of the Bone might 
 
 See Le^. VIII. Exp. 11: 
 h) See leii. VI Exp, VII. 
 
 N 
 
 be 
 
178 
 
 Lecture the Ninth. 
 
 be got out and united with the Water added 
 to excra6t them ; lb as to leave nothing but a 
 little Earth behind, refembling the Allies left 
 upon a dry Calcination in a violent Fire. Whence 
 we are plainly inftrudled in the Nature of animal 
 Geliy, with its Ufes to the Body. And hence 
 alfo we learn the Nature of Mucilages, Size, Glues, 
 and may underftand many things relating to Me- 
 dicine, the animal Oeconomy and Arts. 
 
 30. This Experiment might be rendered more 
 fuccefsful, if wc could procure the tenacious Glue 
 or Cement, which obftinately remains in the 
 Pores of the Bone, even tho* long detained in the 
 Fire. This Glue feems to be an intermediate Sub- 
 ftance, of a middle nature betwixt Geliy and ele- 
 mentary Earth *, whence it were proper to try 
 whether, by grinding the elementary Earth fine 
 and digefting it with Geliy, fome fuch tenacious 
 Glue could not be procured. This alfo might 
 open the way to a Flirtory of Glues, which is ex- 
 treamly wanted in Chemiftry, natural Philofophy, 
 and Arts. 
 
 31. If a promifeous Mafs of elementary Earth 
 be ufed, in (lead of that which retains its natural 
 vafcular Form, a Kind of Callus will be thus 
 produced, infiead of a regular Bone. Whence 
 we may be enabled to judge of the Nature of the 
 Callus formed in the Bones of Animals. 
 
 32. After the manner of our prefent Experi- 
 ment, we might alfo attempt to recompofe ve- 
 getable Subjects. But before any thing of this 
 Kind is done to Perfhdtion, Chemiftry will require 
 the Affiftance of mechanical Contrivance, and 
 many Improvements from the Anatomy of Planes; 
 particularly it muft learn to prelerve the native 
 Spirits of Vegetables, upon the Analyfis, or 
 elfe the artificial ways of imitating and intro- 
 ducing fuch Spirits into the Subjeft. Thefe Spi- 
 rits 
 
Of Synthetical Chemifiry. 179 
 
 rits are extreamely apt to fly ofr with Heat, yet 
 may in good Meafure be colleded and prefcrvcd 
 by Art. And unlefs they are thus prefer'ved, the 
 Subjedls will want their native Taftes and Odours, 
 which depend upon thefe Spirits, or fubtile, vo- 
 latile Matters. 
 
 33. The higheft Degree of Recompofition is, ^erfeSi 
 when a Body is perfedlly refolved into its Prin- 
 ciples, (fuppoie a Vegetable Subjecl into Water, 
 
 Salt, Oil, and Earth) and thefe are again put to- 
 gether, fo as to form a Subjedl undiftinguifhable 
 - from the Original. In order to attain this 
 Perfedion, let the thing be firfl: tried in fimilar, 
 unorganized Bodies; as Glafs; Turpentine, Am- 
 ber, Vegetable Juices, Wines, Sulphurs, Ores, 
 proceeding by flow Degrees, up to the more 
 diflimilar and organical Bodies ; fuch as vegetable 
 and animal Subjedls. 
 
 34. We have feen that, in many Cafes, a true 
 Refolution and Recompofition are prafticable; 
 and as Chemiflry improves, the Bufinefs of Ana- 
 lyjis Synthejis mult likewife improve. 
 
 35. But let it be obferved, that the Power of The lm« 
 Chemiflry is not limited to the Bufinefs of jufl 
 Refolutions and Recompofitions : it can produce 
 numberlefs Effedts without going to this Exadt- 
 
 nefs. Thus it already analyfes and recompofes, 
 or feparates and mixes, all the natural and arti- 
 ficial Bodies, in its own imperfedt manner. And 
 thus it has furnifhed us with all Chemical Me- 
 dicines; as Tindtures, Extradts, Spirits, Oils, 
 
 Waters, Eflences, ^c. and the feveral Commo- 
 dities of Sugar, Wine, Alum, Salt, Por-i\fh, 
 Aqua-Fortis, Oil of Vitriol, Soap, Glafs, 
 iSc. lAc, For without attempting a perfedt Se- 
 paration or Recompofition of the chemical Prin- 
 ciples, a grofs Separation or Mixture of two or 
 three of them v/ill frequently afford very ufe- 
 
 N 2 ful 
 
i8o Lecture the NiNTri, 
 
 ful Subftanccs *, fo that Chcmiftry, tho’ it remains 
 imperied', is ftill highly ferviceable. 
 
 Axioms and Canons. 
 
 1. We learn from the preceding Enquiry, that 
 we cannot fafely conclude Bodies to have been 
 originally compofed of the fame Principles, into 
 which the Fire refolves them a). 
 
 2. That as the Fire, in many Cafes, proves 
 a juft Analyfer, and refolves Bodies into their 
 conftituent Parts, without Alteration ; fo, in 
 others, it quite perverts and changes their Na- 
 ture and Properties; efpecialiy by fcorching the 
 Oil of a Subjed which abounds therewith h), 
 
 3. That the perfed Regeneration of Bodies can 
 take place in fuch Cafes only where the Fire, or 
 other Inftrument, is a true Analyfer, without 
 adding any extraneous thing of its own, or any 
 way altering or fubverting the Nature of the Parts 
 feparated c ), 
 
 4. That the Bufinefs of Rccompofition is to 
 be diftinguifbed into three Kinds, viz, mineral, 
 vegetable, and animal, differing in Degree of Fa- 
 cility; the mineral Kind being the eafieft, and 
 therefore to be firft cultivated, in order to im- 
 prove Synthetical Chemiftry, and render it more 
 advantageouQy pradicable in organ ical Bodies 
 
 5. That Synthetical Chemijiry is more imper- 
 fed than the Analytical-^ or. that the prefent 
 Chemiftry divides natural Bodies more perfedly 
 than it puts them together again, for want of 
 more proper Analyfers than Fire, and more 
 
 a ) See §. 3 . Sc Exp. I. 
 
 b) See Exp. I. Seealfo Left. VIII. Exp. II. 
 
 c) Exp. I, II, III, IV. 
 
 iij See Exp. 1, III, IV. 
 
 fuit- 
 
Of Synthetical Chemijlry. 1 8 1 
 
 fuitable Methods and Menftruums than are hi- 
 therto difcovered a), 
 
 6. That a new Compofirion is ufually made in 
 every chemical Rcfolution. Thus when Nitre is 
 feparatcd into an acid Spirit, its fixed Salt re- 
 mains compounded with the Oil of Vitriol ^). 
 
 When Mercury is feparated from the Sulphur in 
 Cinnabar, the Sulphur remains united with the 
 Quick-Lime, or Iron-Filings When Water 
 is feparated from Brandy, the Water unites with 
 the fixed Salt, and leaves the Spirit to float fe- 
 parate^fj. And this appears to be generally the 
 Cafe ; fo that the Separation is made by fome in- 
 termediate Body, which unites with one Part, 
 and not with the other of the Subject e). Whence 
 we are di reded to find out the Mediums of Mix- 
 ture and Recompofilion^ as well as of Separation^ 
 in order to perfect Analytical and Synthetical Che- 
 mi fir y. 
 
 j. That Bodies endowed with a native Spirit 
 are hard to recompofe, unlefs this Spirit be fome 
 way artificially preferved f). Thus for Inftancc, 
 
 Seeds, Roots, Flowers, efc. may be dried in clofe 
 Glafles, with blind Heads, fet upon a gentle 
 Sand-Heat ; then taking the Subjed out, and 
 feparating its Principles, the Oils and Salts being 
 afterwards impregnated with the native Spirit of 
 the Subjed, remaining in the Blind-Heads, may 
 thus ferve to recompofe the whole in fome toler- 
 able Degree. 
 
 8. That animal Geliy is a Mixture of all the 
 Principles of an animal Subjed, viz, much Water, 
 
 a ) See the preceding Ledlurc, taffitn. 
 
 b ) See Exp. I. 
 
 c) See Led. VIII. Exp AW. 
 el) See Exp. II. 
 i) See Exp, I, II, III, IV. 
 f) See §. 31. iiTf. 
 
 N 3 
 
 a mode- 
 
i 82 
 
 Lecture the Ninth.- 
 
 a moderate Proportion of Oil and Salt, and a little 
 Earth d). Whence we learn the phyfical Caufe 
 why Geliy is nutrimental; why animal Subllan- 
 ces fo much abound therewith ; its Ufes in the 
 Body •, its reftorative Nature, And hence we 
 have a Foundation for the natural and experimen- 
 tal Hiflory of Geilies, Size, Glues, b), 
 
 9. That the Bufinefs of Analytical Chemiftry 
 is deficient, which ought to afford the Rule of 
 operating to Synthetical Chemiftry r). Thus moft: 
 of the Analytical Operations hitherto performed, 
 are but fuperficial Attempts to enter and open the 
 Subftances of natural Bodies ; for v;hich purpofe, 
 in fome Cafes, long Digeftions, repeated Rever- 
 berations, vaporous Mixture, exquifite Triture, 
 continued Fufion, fubtile Precipitation, ^c, are 
 required. Whence the Improvement of Synthe- 
 tical Chemiftry will greatly depend upon the im- 
 provement of the Analytical. 
 
 10. That another way o^ Synthetical 
 
 Chemiftry is carefully to obferve what Steps Na- 
 ture takes in fupplying and recruiting the Bodies 
 of vegetable, animal, and mineral Subftances *, 
 and whether there be any mineral Inftances of Re- 
 generation in Nature, from the direct Principles 
 themfelves without Addition ; or whether this 
 Adlion be not ufually performed by fome certain 
 Affiftance within the Power of Art to procure ; 
 and particularly what is the Office of the Air, 
 Water, and Fire, in bringing about this natural 
 Operation d) in the way of Fermentation^ Putre- 
 faBion^ Accretion^ Nutrition^ and the general 
 Principles of Motion or Life e ) ; and whether 
 
 a) See Exj>. IV. See alfo Lect. VI. Exp. VII. 
 
 b) See above § 28. See alfo Lect VI. Ex^* VII, 
 
 c) See Lset. VIII. and the prefent pojjini, 
 ii) Sac Exp. 1. 
 f) See Lect. VII. pajjim. 
 
 the 
 
Of Synthetical Chemiflry. 
 
 the common Elements do not contribute fome 
 Part of their Subftance, as well as Energy, in 
 the Change From fuch an Enquiry, con- 
 duced in a regular Manner, it Ihould feem that 
 fome capital Canons might be derived for im- 
 proving this grand Part of operative Philofophy. 
 
 ^ See the preceding Leflures upon the Elements. 
 
[ 184] 
 
 LECTURE X. 
 
 CONTAINING 
 
 The Curat ion of Vegetables , or the Means 
 of preparing and fitting ^vegetable Sub^ 
 jeBs for various Ufes, viz. Brewing, Di- 
 ftiiling, Vinegar-Making, &c, 
 
 fhSuh’ \7\T ^ proceeding to examine into 
 
 ;ea, V ¥ Nature of Seminal Vegetation, and 
 
 the Curation or Prefervation of Vegetables, with 
 a View to the Improvement of Chemiftry and 
 the Arts thereon depending.* 
 
 Its Extent. 2. The Subjedt is of large Extent, and if duly 
 profecuted, might tend to the Enrichment of the 
 prefent Arts, or the Difeovery of new ones. 
 For on regulating the Growth, and on the Cura- 
 tion of Vegetable Produdlions, depends the Per- 
 fedlion of Corn, Wines, Malt, Bread, Sugar, 
 Tobacco, Spice, Drugs, Simples, Dying-Stufrs, 
 and the like. And new Difcoveries either in Ve- 
 getation, or Curation, might eafily introduce new 
 Trades; as has been the Cafe in Sugar, Tobacco, 
 V/ines, Spirits, dsfe. 
 
 fhe Pro- 3- Experiments in Vegetation, we here 
 cedure. propofe to fliew the Methods of regulating or 
 condudfing this natural Power for the Service of 
 Arts ; by diredling it to anfwer particular Ends, 
 Thus by (lopping (hort tov/ards the Beginning of 
 Vegetation in Barley, we procure Malt ; and by 
 permitting the Grapes to hang till they grow 
 not only ripe, but almoft dry, upon the Vine, 
 we procure rich fweet* Wines. And thus we 
 
 may 
 
of fegetable Curation. 185 
 
 may ftop Vegetation at any Period, or continue 
 it longer than ordinary, - according as the Occafions 
 of different Arts require. 
 
 4. By Experiments in Curation we would fhew CuratUn 
 the Methods of colleding, preparing, and fe- 
 curing vegetable Commodities; fo as that they 
 
 may long remain found, perfed, and fit for Ser- 
 vice. And thus our prefent Ledure will confift 
 of two Parts ; the one relating to the ways of 
 growing Vegetables, according to the Ufes for 
 which they are intended, and the other to the 
 gathering and preferring them, fo as to have them 
 conftantly ready at hand, when they come to be 
 required in Uie. 
 
 5. Our firft Experiment therefore is calculated 
 to fhew the Method of flopping the natural 
 
 ceis of Vegetation in the Seed ; fo as to prepare mints. 
 Grain, Pulfe, Nuts, Mali, and Roots, for the 
 making of Beer, Vinegar, and Spirits. Our fe- 
 cond is defigned to fhew the Method of curing 
 both fermented and unfermented vegetable Juices, 
 fo as to make them keep found and good for fe- 
 veral Years. Our third Experiment tends to die w 
 the Method of curing vegetable Juices by Decoc- 
 tion, or Infpiffation, for the Service of Brewing 
 and Diflilling. And our fourth and lafl Experi- 
 ment will fhew the Method of curing Yeafl, the 
 Flowers of Wine, and Wine-Lees, for the Ser- 
 vice of feveral Arts. Thefe Experiments now 
 follow in order. 
 
 Experiment I. 
 
 Method of flopping the Natural Procefs of Ve- 
 getation^ with a view to Malting ; or the Pre- 
 paration of Grain., Seedsy Pulfe., Nuts, Majl., 
 and Roots, for the making of Beers, Vinegars, 
 and Spirits, 
 
 6. We 
 
i86 Lecture the Tenth. 
 
 Malting, 6. We plucked up a Parcel of Garden-Beans, 
 after they had been fuffered to lie in the Ground 
 about fix Weeks in the Winter-Seafbn ; and found 
 each Bean beginning to fplit, or feparate, into 
 its two Lohes,, whilft the Radicle was (hot out 
 fome Inches downwards, and had begun to take 
 Root in the Ground *, the Plume alfo, which be- 
 . comes the Stalk of the Bean, being rifen to the 
 height of two Inches. In this ftate we dried a 
 few of thefe over a clear Fire, and thus found 
 them turned to a Kind of Bean-Malt, that tafted 
 fweetilh, bit mealy betwixt the Teeth, and dif- 
 folved freely in warm Water ; fo as to afford a 
 Wort, fit for fermentig with Yeaft intd a Kind 
 of Beer or Ale. 
 
 7. This Experiment inftrudls us in the ordinary 
 Procefs of Malting *, which, in the Cafe of Bar- 
 ley, is conformable hereto, and in the Cafe of 
 Malting Indian Corn is the Procefs itfelf 
 f he Pro- 8. In making Malt from Barley, the ufual 
 
 cefsof Method is to fteep the Grain in a fufficient Quan- 
 Malting. Qp Water, for two or three Days, till it 
 fwells, becomes plump, fomewhat tender, and 
 tinges the Water of a bright brown, or reddifh 
 Colour. Then this Water being drained away, 
 the Barley is removed from the fteeping Ciftern 
 to a Floor, where it is thrown into what they call 
 the JVet-Coucb ; that is, an even Heap, rifing to 
 the Height of about two Foot. In this Wet-Couch 
 the capital Part of the Operation is performed ; 
 for here the Barley fpontaneoufily heats, and be- 
 gins to grow, exactly in the fame manner as in 
 our prefent Example of Beans*, fhooting out firfl 
 the Radicle^ and then if fuffered to continue, the 
 Plume^ Spire^ or Blade, But the Procefs is to 
 be flopped fliort at the Eruption of the Radicle, 
 
 * See below §. 10. See alfo fome -Experiments to this 
 Purpofe in the Philojophical Iranfa^liom, 
 
 otherwife 
 
of Vegetable Cur at ion. 187 
 
 otherwife the Malt would be fpoiled. The way 
 to ftop it is, to fpread this Wct-Couch thin over 
 a large Floor, and keep it turning once in four 
 or five hours, for the fpace of two Days, laying 
 it fomewhat thicker each time. After this, the 
 Malt is again thrown in a large Heap, and there 
 fuffered to grow fcnfibly hot to the Hand, as it 
 ufually will in twenty or thirty Hours time; then 
 being fpread abroad again and cooled, it is thrown 
 upon the Kiln, to be dried crifp without fcorching. 
 
 9. And this is the general Procefs of Malting, 
 w'herein almoft every Maltfter has his fecret 
 particular way of working. But to render the hejl ad^ 
 Operation perfect, the following Cautions muft vantage, 
 be obferved : (i.) That the Barley be newly 
 thraflied, or at lead newly winnowed; (2.) That 
 
 it be not mixed or made up of different Sorts ; 
 
 (3.) That it be not over fteeped in the Ciftern, 
 or ly there fo long as to make it foft; (4.) That it 
 be well drained ; (5.) That It be carefully looked 
 after in the Wct-Couch, fo as to ftop the firft 
 Tendency of the Blade to (hooting ; (6.) To 
 turn the Wet-Couch infide outermoft if the 
 Barley comes (that is, fhoots) more in the middle 
 than on the (ides ; (7.) To keep it duly turning 
 after it is out of the Wet-Couch; (8.) To 
 give it the proper heating in the dry Heap; 
 
 (9.) To dry and crifp it thoroughly upon the 
 Kiln, but without a fierce Fire, fo as to be 
 fcveral Days in drying a Kiln of Pale Malt, 
 
 If thefe Directions be carefully obferved, the 
 Malt will always be good. 
 
 10. The Method of Malting Indian-Corn.^ or 
 Virginia Wheat., is much lefs laborious. For if 
 this Corn be buried two or three Inches deep in 
 the Earth, and covered with the loofe Mould 
 dug up to make room for it, in ten or twelve 
 Days, time the Corn will fprout, and appear like 
 
 a green 
 
i88 
 
 Extended, 
 
 Its Effedls^ 
 and End. 
 
 Lecture the Tenth. 
 
 a green Field ; at which time being taken up^ 
 and waflied or fanned from its Dirt, it is imme- 
 diately committed to the Kiln, and by this means 
 it becomes good Malt, exactly as Beans fo treated 
 would do. 
 
 11. It is obfervable of this Corn, that both 
 its Root and Blade muft (hoot to a confiderable 
 length, before it will make Malt. And perhaps 
 this is the Cafe in all large-bodied Grain and 
 Nuts a ), 
 
 12. It might be of Service to transfer this eafy 
 Experiment to the making of Malt from Barley, 
 Rice, and the other fmall Grains and Seeds: but 
 the Attempt may be attended with Difficulties ; 
 becaufe in the making of Malt, the Barley muft 
 be fuffered to grow in its Root only, and not in 
 the Blade ; whence it would be difficult, at firft, 
 to hit the exadl time for taking it out of the 
 Ground. And, again, as the Grain is fo fmall, it 
 might prove troublefome to feparate it from the 
 Earth or Mould. However, the thing may de- 
 ferve to be tried h ). 
 
 13. It is a Confideration of a higher Nature 
 to determine the phyfical Effect procured by Malt- 
 ing, and whether the End may not be obtained 
 by cheaper and lefs laborious Means. The phy- 
 fical Difference betwixt malted and unmalted Corn 
 appears to be the Produdion, or Extrication, of 
 a fweet faccharinc Subftance in the Malt, which 
 is wanting under that form in the Corn. And it 
 is the fweet Subftance alone, which we require 
 
 a) \t may be worth trying, whether the fame Procefs is 
 not, with due Care, applicable to the Malting of Turnips, 
 Potatoes, Carrots, Parfnips, ^c. 
 
 b) And poffibly fome Contrivance might be found, by the 
 means of large Hair- Cloths, or otherwife, to inclofe the Grain, 
 fo that the loofe Earth Ihould not mix among it ; and at the 
 fame time an Opportunity be afforded, of commodioully ex- 
 smir^ing how far the Barley is come at any time after lying. 
 
Of Vegetable Curation. 189 
 
 in Malt for the making of Beer, Ale, Vinegar, 
 and inflammable Spirits a). But even unmalted 
 Corn, duly treated, may be made to afford Beer, 
 
 Ale, Vinegar, and Spirits: This, therefore, may 
 intimate to us a way of making fuch Liquors, 
 without the formal Extrication of any remarkably 
 fweet faccharine Subftance. According to fome 
 Trials we have made, unmalted Corn affords half 
 the Quantity of inflammable Spirit by Fermen- 
 tation and Dift illation, as the fame Corn would do 
 when malted. And fuppofe that unmalted Corn 
 were to be made into a Kind of Dough, or 
 Pafle fermented with Yeaft, as is ufuaj for Bread, 
 and then baked j would not this be a cheap Subfti- 
 tute for Malting At leaft, it deferves to be 
 tried, how much Beer, Ale, Vinegar, and Spirit, 
 might be procured this way, compared with that 
 other of Malting. 
 
 14. On the other hand, if only a fweet faccha- 
 rine Subftance be required in Malt, are there not 
 cheaper and eafier ways of procuring it than by 
 Malting? Do not many Trees afford fuch a fac- 
 charine Juice, by Tapping in the Spring, with- 
 out prejudicing the Trees ? Is not young green 
 Corn itfelf remarkably fweet *, and does not this 
 fweet Juice enter the Compofition of the Ear, 
 and there remain fixed, or almofl loft in a fac- 
 charine Form, till recovered by Malting ? Here 
 is a Door opened for explaining the Nature of 
 Sweetnefs, and deducing the particular Hiftory 
 of Sugar. Such a Work, for its Ufefulnefs in 
 Trades and ordinary Life, we wifh were extant 5 
 and till fome confiderable Progrefs is made there- 
 
 -j) Se® Lea,V\l. Exp. I, II, IV. 
 
 h) They are faid to brew after this manner in fome Coun- 
 tries. 
 
 in 
 
Lecture the Tenth. 
 
 in, the Art of Malting, and all thofe that depend 
 upon it muft remain fhortof perfection, 
 
 15. Thofe, who are difpofed to go upon the 
 Enquiry, may pleale to compare the Art of 
 Starch -Making with that of Malting, and par- 
 ticularly try whether fome confiderable Ufes 
 may not be made of the Refufe Liquors pro- 
 duced in both Arts. The high-coloured Liquor 
 drawn from the Barley in the fteeping Ciftern 
 is a vegetable TinCture, that might, if not 
 by itfelf, yet by being ufed infread of Water to 
 ground Malt, be worth fermenting and diftilling 
 for Spirit; and the Starch-Makers refufe Liquors 
 have been obferved to contain a Quantity of in- 
 flammable Spirit. 
 
 16. Our prefent Experiment may in this re- 
 fpeCf be made general, that it fhews us there are 
 different times of fhopping, or preventing, the 
 farther Growth of Vegetables, for the Service of 
 Arts. And this Dodrine may be extended to 
 the forming a Set of general Rules, for gathering 
 the different Parts of Plants, at different Seafons 
 of the Year, for different Ufes. 
 
 17. Thus Roots, for inftance, to be had per- 
 fect, fhould be gathered and dried in the Spring, 
 before the Leaves are formed ; Leaves fhould be 
 gathered when they are fully opened, but before 
 the Flowers appear ; Flowers when they are not 
 fully opened ; and fome, as red Rofes, in the Bud. 
 Seeds are to be gathered when full ripe, and be- 
 ginning to dry, before they fall fpontaneoufly v 
 and Trees are generally befl felled and flawed for 
 their Bark in the Beginning of the Spring. But 
 all this is to be underftood of the common Ufes 
 of the Subjects ; for there are many particular 
 Occafions, which require them immature. Thus 
 Buckthorn-Berries, /jfhould be ripe gathered for 
 
 making 
 
of Vegetable Curation. 191 
 
 making the Syrup, but unripe, for making the 
 Painter’s Colour called Sap-Green, 
 
 Experiment II. 
 
 A Method of Curing both unfermented and fermented 
 vegetable Juices, 
 
 18. (i.) We melted Brimftone in an Iron Matching 
 Ladle, and dipping flips of coarfe linnen Cloth or Fumi- 
 therein, made what the Wine-Coopers commonly 
 
 call Match. (2.) We took a Hip of this 7'^ 
 
 . Match, and fetting one end thereof on fire, 
 put it into the Bung-Hole of a Cafk, which being 
 at firft loofely flopped, fuffered the Match to 
 burn nearly out. "Then the Bung being driven in 
 tight, we fet the Cafk afide for an hour or two, 
 and found that this Operation communicated a 
 violently pungent and fufe)cating Scent to the Cafk, 
 with a confiderable Degree of Acidity, which is 
 the Gas and acid Spirit of the Sulphur. We now 
 filled the Cafk with a very frnall Wine, which 
 had fcarce finiflied its Fermentation *, and bunging 
 it down tight, we put it in a proper place to clarify. 
 
 19. This is the common Method of matching 
 Cafk for Wines, but particularly for Stums. It 
 is an ufeful Experiment *, for poor Wines could 
 fcarce be kept potable a fev/ Months wihout it ; 
 nor could Stums be prepared in large quantities 
 by any other Method commonly known. 
 
 20. By Stum we underfland the unfermented stum 
 Juice of the Grape, feveral times racked znd^^bat, 
 drawn from its Sediment, the Cafk being every 
 time thus fumigated with Brimflone, to prevent 
 
 the Liquor from fermenting, as it would otherwife 
 readily do and fo become Wine. It is the Fume 
 of the burning Sulphur which thus flops all Ten - 
 dency to Fermentation, and continues the natural 
 Juice of the Grape in a fweet flate, fit to be rea- 
 dily 
 
jg2 
 
 IfECTURE THE TenTM. 
 
 dily mixed with Wines inftead of Sugar; for 
 which purpofe it is very much ufed ih Holland^ 
 and other Countries, as alfo for giving a new 
 Fret^ or Brilknefs, to decayed Wines ; fo that 
 very large Quantities of this Stum are annually 
 imported to all Parts along with the Foreign 
 Wines. And after the fame manner a Stum is 
 prepared in England from the Juice of Apples, 
 which ferves the ordinary purpofes of the Wine- 
 Cooper. 
 
 Inconnjenl- 21. The principal Inconveniences in this Me- 
 ernes of thod of matching the Calk are thefe ; (i.) that 
 Matching, jj- communicates a naufeous fulphureous Tafte and 
 Smell to the Wine ; and (2.) that it is not appli- 
 cable to red Scums, or red Wines, without greatly 
 impairing, or almoft deftroying their Colour ; 
 whence the Stums in common Ufe are always 
 white, the Produce of white Grapes. And be- 
 caufe this Method of Matching does not fuit with 
 red Wines, hence it is, that all red Wines are 
 ufually dofed with Brandy in order to preferve them. 
 And for Wines in general, it might very well fuf- 
 jfice to burn a little Spirit of Wine in the Cafk; 
 and if they want Strength, or Spirit, to preferve 
 them found, to add Brandy or Spirit of Wine, pro- 
 portionabiy. By which means they may be pre- 
 ferved without any naufeous Smell, or Tafte, 
 which always attend the Way of matching; tho* 
 matched Wines lofe of their fulphureous Tafte, 
 and Odour by long keeping. But for Stums, 
 there is no other Way commonly known and prac- 
 tifed, to preferve them, but by ufing the Fumes 
 of Sulphur. 
 
 The Ex- 22. The Experiment however is almoft gene- 
 feriment ral, and may be applied to advantage in the cafe 
 extended. Qf fermented Liquors, and again to unfermented 
 vegetable Juices ; fuch as thofe of Citrons, Quin- 
 ces, Oranges, fcfr. which it prevents from run- 
 ning 
 
Of Vegetable Curation. 193 
 
 ning into Fermentation or Putrefadiiion. And 
 this Effe6l it feems to have, chiefly by fciffening 
 the Air, or weakening its natural Elafticity For 
 
 as all vinous Fermentation is found to generate 
 Air, fo the burning of Sulphur is found to ftiffen 
 or deftroy Air. And hence it feems to be, that 
 the Fume of burning Brimflone readily checks 
 the Fermentation of Liquors ; fo that if a Cafk, 
 by fretting or fermenting, appears ready to burft: 
 its Hoops, a Difli of burning Brimflone held un- 
 der it will foon quell the Motion : which is one 
 known Method of checking or fupprefTing vinous 
 Fermentation* 
 
 Experiment III. 
 
 Method of curing vegetable Juices by DecofHon^ 
 or Injpijfation, 
 
 25. We made an Infufion of Malt, in the com- tVort in- 
 mon Manner of Wort for Beer or Ale; then let-//'#'^^^* 
 ting it fland to clarify, we decanted the clear Li- 
 quor, and boiled it over a foft Fire to the Con- 
 jiflence of Treacle: in which State it will long 
 keep found, or fit for making Beer, Vinegar, or 
 inflammable Spirit. 
 
 24. This Experiment fhews us ageneral Way of "The Expe^ 
 reducing fermentable Subjects to a fmall Compafs, 
 
 and of fecuring them againfl external Injuries. 
 
 Thus a Kind of Treacle from Malt might be 
 procured in cheap Years, for the Service of the 
 Vinegar-maker, the Brewer, and the Difliller. 
 
 The Method is likewife applicable to any other 
 fweet or faccharine Juice ; as that of Grapes, the 
 Tappings of Trees, the fermentable Juices of 
 Summer- Fruits, and of certain fweet Roots, as 
 Parfnips, 
 
 25. Thefe infpiflated Juices, if not boiled too 
 high or fcorched in the Operation, are eafily 
 
 * See Mr. Hale‘s Vegetable Staticks* 
 
 O brought 
 
194 - 
 
 Lecture THE Tenth. 
 
 brought back to a due Degree of Thinnefs with 
 Water, and fermented in the fame Manner, and 
 for the fame Purpofes, as they might have been 
 before they were boiled : So that Beer, Vinegar, 
 or Spirits may be thus commodioufly procured, 
 at any Time, even in hot Climates *, and it ftould 
 feem that Brewers and Diftillers might alfo reap 
 fome Advantage from a prudent Ufe of this Ex- 
 pedient. 
 
 26. The Wine-Merchant might thus order the 
 Juice of Grapes, or Stum, to be boiled down in 
 Wine Countries, and fo left fit to be reduced by 
 Water and fermented into Wines in others. And 
 for this Purpofe the poorer Vintages might fervc, 
 as well as the rich ; excepting only that the Rob, 
 when reduced by W’ater, would not afford fo 
 much Wine as the thicker or richer Juices. But 
 the Operation mult be performed with confider- 
 able Exadnefs, to make it fucceed fo as to pro- 
 duce artificial Wines perfedly like the natural. 
 
 27. This Procefs aifo feems applicable to Hops, 
 which in cheap Years, may be thus made into a 
 Kind of Extrad, without any Lofs of their valua- 
 ble Parts j whereby the numerous Contingencies 
 attending that Commodity, might in good Meafure 
 be prevented. But there w^ould here be Danger of 
 Fraud *, becaufe the Extrads of Gentian, Centaury, 
 or other bitter, ftomachic Vegetables might be 
 mixed with the Extrad of Hops, fo as not to be 
 cafily difcovered. Yet perhaps this Inconvenience 
 would not be greater than that generally fuffered 
 already ; for many, no doubt, are well affured by- 
 Experience, that the Extrad of Gentian is a 
 wholefome Bitter, which might very well fupply 
 the Place of Hops in Brewing. 
 
 28. A Procefs fome what of this Kind is fre- 
 quently pradifed in Wine-Countries ; viz, either 
 
 by 
 
Of Vegetahh Curation. 195 
 
 by fufFering the Grapes to grow almoft dry 
 upon the Vine ; or elfe by boiling ^own their 
 Juice, till it becomes fufficiently thick to afford 
 luch rich Wines as Canary or Frontignac ; whofe 
 Strength may be readily imitated by adding 
 a lels Proportion of Water to the Rob, or infpif- 
 iated Juice of Grapes, in the Manner above ex- 
 plained 
 
 29. Before we quit this Procefs we would re- 
 commend it to be tried, upon the Juice that may 
 be eafily expreffed from a vegetable Subjedl com- 
 monly thrown away as ufelefs : we mean the 
 Shells of green Peafe, which by being barely 
 boiled in Water, communicate a faccharine Sweet- 
 nefs thereto j fo that the Liquor has been made 
 into tolerable Drink, and a good Spirit. 
 
 Experiment IV. 
 
 ^ Method of curing Teaft^ the Flower of Wine^ and 
 alfo Wine- Lees ^ for the Service of Dijtilling^ 
 Wine-Makingi Vinegar-Makings &c. 
 
 30. We took a Quantity of common Ale-Yeaft, Teaflcund 
 ^nd putting it into a clofe Canvas Bag, gently andpre- 
 fqueezed out the Moiflurc in a Screw-Prefs, till 
 
 the remaining Matter was left as hard as Clay ; 
 and in this State having packed it clofe in a tight 
 Cafk, and fecured it well from the Air, it kept 
 frefh and found for feveral Months \ as has been 
 often experienced by others. 
 
 31. This is an Experiment of confiderable Ufe Ufe, 
 to Brewers and Diftillers, who employ very large 
 Quantities of Yeafl, and yet feem in Englajtd 
 
 to have no good Method of preferving it, or rai- 
 ling Nurferies thereof; for Want of which they 
 fuftain a confiderable Lofs. Whereas the Brewers 
 in Flanders make a great Profit, by fupplying the 
 
 * §. 23 -- 27 . 
 
 O 2 
 
 Malt- 
 
196 
 
 ^he Expe- 
 riment 
 extended. 
 
 Ferpa 
 
 (duration 
 
 mhat. 
 
 Lecture the Tenth. 
 
 Malt-Diflillers of Holland with Yeaft, which is’ 
 rendered lading and fit for Carriage, after the 
 Manner of our prefent Experiment. 
 
 32. The fame Method is practicable to much 
 greater Advantage in the Yeafl of Wine, and 
 in Wine-Lees, it they could be imported into 
 England. For by this Means we might eafily imi- 
 tate the Wines and Brandies of foreign Growths; 
 the Lees and Yeaft of Wine readily affording an 
 effential Oil, by Difdllation, of which a fmall 
 Proportion will flavour a large one of Wine or 
 Brandy. But a fliorter and more perfeCt W ay is 
 to let any taftelefs, or other proper Wine, fret 
 or ftand, for fomeTime, upon fuch Lees, orWine- 
 Yeaft, whereby it will to great Advantage acquire 
 the natural Tafte and Flavour of the Wine, 
 to which the Lee, or Yeaft, belonged. 
 
 33. Thus we have given a few Examples of 
 Vegetable Cjuratioit.^ on which the Improvement of 
 'feveral Arts* depends. We cannot go through all 
 the Species of it, for that would be an immenfe 
 Labour ; nor are Men hitherto arrived at the 
 perfect Method of preferving Vegetables in their 
 natural Form, with their Colours, Odours, and 
 other fenfible Qualities, for anyNumber of Years. 
 Yet fomething conflderable might be done in this 
 Way, by proper Application. Fruits may long 
 be preferved frefli in Spirit of Wine, firfl well 
 faturated with the Skins and tinging Farts of the 
 Fruit. And many of them may be tolerably 
 preferved in perfectly fermented Liquors, which 
 generate no more Air. The more folid Kinds of 
 Subfi'ances may be cornmodioufly cured, by 
 gently drying them in the Sun, Shade, or other 
 flack Heat. Thus Peafe^ or Beans, being dried 
 young in a flack Oven, in their proper Seafon, 
 may be boiled green and tender, in the Winter, 
 alnioil like thofe new gathered. Certain Ways of 
 
 piC- 
 
Of Vegetable Curation. 197 
 
 preferving Fruits, and other vegetable Subjeds, 
 both in a dry and moift Form, with Sugar, are 
 now generally known : But there are fome extra- 
 ordinary Means of curing feveral particular Kinds 
 of Bodies referved as Secrets by Artifls ; tho* 
 even thefe might be exceeded, if we had a tho- 
 rough Knowledge of the prefent Subjed. The 
 Defign might alfo be extended to the animal 
 Kingdom, under the Name of Animal Curation ; 
 the compleat Art whereof would prove highly 
 ufeful at Sea. 
 
 Axioms and C a n ,o n s. 
 
 1. We learn from the preceding Enquiry, that 
 Men have Power to ftop the Courfe of Na- 
 ture in Vegetation, fo as to make this Principle 
 anfwer their own particular Ends and Defigns ; 
 whence Arts may receive confiderable Improve- 
 ments a). 
 
 2. That the Art of Malting is farther improve- 
 able by a general Acquaintance with the Nature 
 of Vegetation^ vegetable Juices, the Art of Fer- 
 mentation, and the Art of Sugars b). 
 
 3. That the Labour and Expence attending 
 the Art of Malting may, in fome Meafure, be 
 faved, by procuring and feparating the fweet 
 Juices of Vegetables as Nature affords them ; or 
 by boiling them down to a Treacle or faccharine 
 Subfiance c). 
 
 4. That there are different Seafons of the Year 
 peculiarly fitted to the colleding or procuring of 
 •thefe Juices, and all other vegetable Matters, ac- 
 cording as they are required ripe or immature 
 
 a) See Exp. I. 
 
 b\ See Exp. I. n. 
 
 c) See Exp. I. III. 
 
 .#') See Exp, I. v 
 
 o 3 
 
 f. That 
 
198 Lecture the Tenth. 
 
 5. That the Fumes of burning Sulphur have a 
 great anti-fermentative, anti- corruptive, or pre- 
 lervative Power upon vegetable J uices a) •, and this 
 without rendering the Liquors unwholefome, 
 tho’ the Fume is difagreeable, and of itfelf fuf- 
 focative. 
 
 6. That the Fumes of burning Sulphur have 
 a Power of difcharging the Colour of red 
 Wines a ) ; and on a like Account thefe Fumes 
 are ufually employed for the Blanching of Silks, 
 Flannels, 
 
 7. That Vegetable Curation depends chiefly upon 
 the Exclufion of the Air and all fuperfluous 
 Moilture; and this either fingly or conjointly h). 
 
 8. That Vegetable Curation confifts in keeping 
 all the Principles of a vegetable Subject together 
 iindeftroyed, in their natural Texture or Arran- 
 gement b). 
 
 9. That all fweet vegetable Juices may be pre- 
 ferved found and ferviccable, by infpiflfating them 
 over a foft Fire ; fo as to throw olF their fuper- 
 fluous aqueous Parts, and leave the fweet orfaccha- 
 rine Subfhance behind, in a ftate fit for Fermen- 
 tation, upon the Addition of frefh Water c). 
 
 10. That feveral bitter vegetable Juices, ca- 
 pable of anfwering the End of Hops in Brewing, 
 may be infpiffated by the Fire, and preferyed for 
 that Purpofe r). 
 
 11. That thofe extremely corruptible Sub- 
 ftances, Yeaft, the Flowers of Wine, and Wine- 
 Lees, may be preferved found, barely by freeing 
 them from their fuperfluous Moifture, and fecur- 
 ing them from the external Air and too great 
 Pleat d). 
 
 a) See £x/> II. 
 h) Exp. II, III, IV. 
 e) See Exp. III. 
 
 ^ Exp.IY. 
 
 12. That 
 
Of Vegetable Curation. 199 
 
 1 2 . That the Bufinefs of Vegetable Curation may 
 receive great Improvements by a proper chemical 
 Enquiry, made with a dired View to this Sub- 
 je 6 t ; from whence many farther Advantages are 
 derivable to Arts and Trades, particularly to the ^ 
 Sugar-Colonies abroad, to Brewers, Wine-Ma- 
 kers, and Diftillers in hot Countries ; and that 
 the Enquiry likewife might be advantageoufly 
 extended to Animal Curation 
 
 ^ See Exp, IV. 
 
 O4 
 
 LEC- 
 
[ 200 ] 
 
 I 
 
 LECTURE XI. 
 
 CONTAINING 
 
 Ways of illii ft rating and improving the. Arts 
 depe?iding upon Vegetable Fermenta- 
 tion; particularly Brewing, Diftilling, 
 Vinegar-Making, &c, 
 
 ^he !• "T FT our lafl: Le6lure we endeavoured to fhew 
 Subjeu, ^ the Method of procuring certain vegetable 
 Commodities, and preferving them uncorrupted, 
 for the Service of Arts : In our prefent, we fhali 
 confider fome Ufes of thefe Commodities, when 
 thus preferved ; or the Ways of employing them, 
 fo as to afford various Preparations for the com- 
 modious carrying on of Trade, and the Bufinefs 
 of ordinary Life. 
 
 2 . As our Confideration is retrained to the 
 vegetable Kingdom, the Arts that will chiefly 
 come before us at prefent are, thofe of Wines, 
 Sweets, Malt-Liquors, Vinegars, and Brandies ; 
 in all which we have already made fome Progrefs 
 But there remains much behind for the Improve- 
 ment of thefe Arts ; which lie in a State far from 
 that Simplicity, on which their Perfedfion feems 
 to depend. 
 
 The Depgn 3* Thefe Arts v/e fliall here endeavour to im- 
 of a:e jix- prove by four diredl Experiments. The frft 
 ferimentsi capital, and calculated to fhew the Method 
 ot reducing vegetable Juices, cured by Decoc- 
 
 ^ S^e LeCl> X, 
 
 tion. 
 
201 
 
 of Wines and Spirits. 
 
 tion or Infpiffation * , back to a State fit 
 for affording Vinegars, Wines, and Brandies by 
 Fermentation ; and at the fame Time to exhibit a 
 new Method of making an artificial Muji., or 
 Stum., as good as the natural, and equally fit for. 
 refermenting, fretting, improving, and making 
 Wines, Vinegars, and Spirits, in all Countries. 
 
 4. The fecond Experiment will exhibit the com- 
 mon Methods of forcing, or fining down, ferment- 
 ed vinous Liquors, fo as to render them expe- . 
 ditioufly bright or clear, and fit for Ufe. 
 
 5. The third Experiment will fhew a Method 
 of converting White Wines into Reds ; and of 
 recovering, or improving, the Colour of decayed 
 red Whines. 
 
 6. The fourth., a Method of concentrating 
 Wines, Vinegars, or Malt-Liquors, for Carriage, 
 or Exportation. 
 
 7. The fifth will fhew a Method of recovering 
 prick’d Wines. 
 
 8. The fixth and laft will fhew a more profi- 
 table Method, than that commonly ufed in Eng- 
 land, of fermenting Malt for Diflillation, or the 
 Produ( 5 lion of common inflammable Spirits. 
 
 Thefe Experiments now follow in their Order. 
 
 Experiment I. 
 
 fo (Joew the Method of reducing vegetable Juices, 
 cured by Infpiffation or BecoSiion, back to a 
 State fit for affording JVines, Vinegars, and Bran- 
 dies, by Fermentation \ and at the fame Time to 
 exhibit a Method of making an artificial Muji, 
 or Stum, as good as the natural, and equally fit for 
 refermenting, fret ting, improving, or makingWines, 
 Vinegars, and Spirits, 
 
 9. V/e took three Pounds of white Lump Su- Artificial 
 gar well cleanfed of its Treacle, and melting it Muftpre- 
 
 • Sec Lea. X. Exp. III. . 
 
 in 
 
202 
 
 
 ^he Expe- 
 riment 
 hwo de~ 
 duced. 
 
 Lecture the Eleventh. 
 
 in three Quarts of fair Water, added in the 
 boiling half an Ounce of finely pulverized Rhenijh 
 Tartar-, which diflblved with a remarkable Ebul- 
 lition, and gave a grateful Acidity to the Li- 
 quor. Then taking the Veflel from the Fire, 
 and fuffering it to cool, we thus procured a Mufi^ 
 which in all refpedls refembled the natural tart 
 and fweet Juice of a white flavourlefs Grape, 
 when that Juice is well purified, and often 
 racked from its Sediment, in order to make 
 Stum. And if our artificial Muft be Hummed, 
 that is matched, or well fumigated with burning 
 Brimftone, after the Manner fhewed in our laft 
 Ledure a it thus becomes a perfect Stum - ; which 
 may be made of any Flavour, at the Difcretion 
 of the Artift. 
 
 10. This Experiment is fo pregnant, that it 
 might deferve to have its Ufes explained by an 
 exprefs Treatife b ), It affords abundant Inftruc- 
 tion for improving the Arts of Sweets, Stums, 
 Wines, Vinegars, and Spirits ; it likevvife affords 
 fome ufeful Inftrudions about the Nature of fweet 
 and tart vegetable Juices, and the Ways of imi- 
 tating them by Art. But thefe Particulars we 
 can only juft touch upon for the prefent. 
 
 1 1. The Experiment itfelf was formedaipon the 
 Analyfisof the Juice of the Grape before Fermen- 
 tation ; which Juice, to the Senfes, appears no 
 other than a faccharine Subftance diffolved in 
 Water, with the Addition of a tartarous Acid : 
 And this being fully confirmed by a chemical 
 Refolution, it was hence eafy to exped, that if 
 Tartar, which is the natural Salt of Wine, or of 
 any fweet vegetable Juice fermented, could be 
 artificially diffolved in a proper Mixture of Sugar 
 and Waterj^ it wouM give an exaft Refemblancc 
 
 «) Exp. II. 
 
 i See the Appendix to this Lefture. 
 
 of 
 
Of Wines and Spirits. 203 
 
 of the thing. Accordingly it was found upoil 
 Trial that Tartar might be thus dilTolved, fo aS 
 to communicate an agreeable Acidity to Sugar, 
 and thus to imitate, in great PerfedHon, the natu- 
 ral fwect Juices of Vegetables, without their par- 
 ticular Flavours : and hence our Experiment dif- 
 covers to us the Nature, Ufe, and Ferfedtion Of 
 the Art of Sweets. 
 
 12. By a SMet is underftood any vegetable 
 Juice, whether obtained by Means of Sugar, Rai- n;jhat, 
 lins, or other Foreign or Domeftick Fruit, which 
 
 is added to Wines in order to improve them. 
 
 Whence we fee that the Art of Sweet-Making 
 ttiight receive a high Degree of Improvement, 
 by ufing pure Sugar as one general wholefome 
 Sweet, inftead of thofe infinite Mixtures of Ho- 
 ney, Raifins, Syrups, Treacle, Stum, Cyder, 
 
 Cij’r. wherewith the Sweet-Makers fupply the Wine- 
 Coopers, to eke out or amend their Wines. For 
 pure Sugar being added to any poor Wine will 
 ferment therewith, improve it, and bring it to a 
 ptoper Degree of Strength and Vinofity. If the 
 Wine to be thus amended is tart of itfelf, no 
 Tartar fhould be added to the Sugar ; but if it 
 be lufcious or too fweet, then the Addition of 
 Tartar is proper. 
 
 13. The prefent Experiment adds no lefs Im- Extended, 
 provement to the Art of Stums^ which may per- 
 haps be hence brought to its Perfedlion. And 
 
 here we defire the Men of Bufinefs would duly 
 refledl, that wherever Sugars go, there go in a 
 folid form Stums^ Wines,, Vinegars^ and Brandies \ 
 that is, the adual Matter out of which, by the 
 bare Addition of Water, thefe feveral Commodi- 
 ties may be readily prepared. For it is by no 
 Means necefiary that Sugars Ihould be imported 
 and exported in a liquid Form, for the making 
 
204 
 
 Farther 
 U/es in ihi 
 ^ retire of 
 Wines. 
 
 Jnd Vine- 
 gars. 
 
 Lecture the Eleventh. 
 
 of Stums, Wines, (^'c. becaufe it is fo eafy to add 
 the l ariar and Vv^ater in any Port they arrive at. 
 
 14. Our Experiment alfo points out the Way 
 of perfeding die y/r/ 0/ Wines^ by reducing the 
 .con-ponent LViatcer thereof to a fmall Bulk, and 
 occafionally,in any Climate, bringing it back with 
 Water into a Muff ; which Muft may be tinged 
 of any Colour, or impregnated with any Fla- 
 vour, To as to be fermented into a Wine of any 
 Species or Denomination. Thus if a few Drops 
 of the elTential Oil of Nutmeg, or Cinnamon, 
 were to be rubbed with a little Sugar into a Kind 
 of Elceofaccharum and then mixed with our 
 artificial Mult, or Stum, the Wine made of it 
 would have a very grateful Odour and Flavour. 
 And fo if an effential Oil were procured from the 
 Lees of any particular Wine, and introduced in- 
 to our artificial Stum, after the fame Manner, the 
 artificial Wine would thus have the Odour and 
 Flavour of the natural Wine that afforded the 
 Lees ; bating for the Roughnefs, Hardnefs, or 
 Drynefs given by the Hufk and Stone. For our 
 artificial Muft has no Flavour or Colour of its 
 own, but readily receives and becomes impre- 
 gnated with either by Art. And how far this 
 Experiment may be ufeful in teaching a Method 
 of making a rich concentrated Wine, for the ex- 
 temporaneous Improvem.ent of the poorer Sorts, or 
 for making a ferviceable Kind of extemporaneous 
 W' ine, barely by mixing with Water, we recom- 
 mend to the Trial of thole who have a Talent at 
 this Kind of Experiments. 
 
 15. The Art of Vinegar -Making may alfo pof- 
 fibly receive a high Degree of Improvement by 
 Means of the prefent Experiment, as it affords 
 us a Method of diffolving Tartar in Water, on 
 which the whole Art of Vinegar- making feems to 
 
 See hereafter, LcSl.yUll. Exp.lY, 
 
 depend 
 
Of TVines and Spirits. 20j 
 
 depend' For there are many phyfical and che- 
 mical Reafons and Experiments, to fhew that 
 Vinegar is no more than a particular Kind of 
 fluid ’Tartar, And the Art of making Vinegar 
 would then be perfedt, when it could readily, or 
 extemporaneoufly, prepare and concentrate the 
 Commodity ^ fo as to give it a Kind of folid or 
 confiftent Form, which fhould render it durable, 
 bring it into a fmall Bulk, and leave it fit to be 
 reduced by Water into a fluid Form, for Ufe in 
 all Climates. 
 
 1 6. We plainly fee that the original compo- 
 nent Matter of Vinegar, which is Sugar, lies in 
 a fmall Bulk, and may be readily converted by 
 Water, Air, and Heat into Vinegar Sugar 
 in the A( 5 l of Acetiflcation feems wholly converted 
 into a fluid Tartar; and if the aqueous Liquor 
 be feparated from Vinegar, we find the Vinegar 
 is thereby rendered the ftronger : infomuch that 
 if Vinegar were to be highly concentrated by 
 Congelation, it would become almoft folid, or 
 a Kind of adlual 'i'artar. Whence the Rule is 
 eafy, that in order to make an almofl folid Vi- 
 negar, we fhould endeavour to diflblve Tartar 
 in an aqueous Liquor. Whence, for perfedting 
 the Art of Vinegar-Making, we recommend the 
 diflblving of Tartar largely with Sugar, or Trea- 
 cle, and the ftrongefi: Vinegar, by repeated Im- 
 bibitions, Heat, and a proper Management. 
 
 17. We proceed to fhew fome Ufe of our Ex- Ik the Dt- 
 periment in the Art of Difbillation ; which Art 
 
 like wife might pofTibly arrive at Perfedlion by its 
 Means. It is generally known that a taftelefs, 
 flavourlefs, yet perfedfly vinous and cheap Spirit, 
 is the grand Deflderaium in the Art of Diftilling : 
 
 Now fuch a Spirit feems eafily procurable from 
 our Stum, made highly acid by the Addition of 
 ^ See Lea, VI. Exf, II. 
 
 Tartar, 
 
2o6 
 
 Lecture the Eleventh. 
 
 Tartar, and fermented till that Acidity prevails, 
 as it foon will do, fo as to prove a true Vinofity. 
 And thus a highly vinous, yet flavourlefs Spirit, 
 may be obtained at a very reafonable Charge, if 
 a Man thoroughly underitands the Art of Fer- 
 mentation. And fuch a Spirit might be readily 
 flavoured and converted into French Brandy, Ar- 
 rack, or any other Kind of Spirit, that commonly 
 fells for a much greater Price a), 
 farther 1 8. Thefe Particulars, with fcverai others that 
 might be mentioned, hold of our Experiment in 
 its perfect State : for to reduce fweet vegetable 
 Juices to a pure white Sugar, without any Par- 
 ticipation of Treacle, is an extreamly Cu- 
 ration^ which coft much Labour before it was 
 difcovered. But nov/ the thing is common, we 
 jfeem almoft to negledt it ; at leafl: do not enquire 
 into the farther Ufes of fo capital a Difcovery, 
 tp the apparent Detriment of the Sugar-Trade, 
 and the Colonies thereon depending. 
 
 1 9. Thp’Curation by bare Decodtion, or In- 
 ipiflatipn, is of a lower Clafs, yet flill it has its 
 Ufes h)\ for even Treacle is an ufeful Sub- 
 ibapcp : But the Rob of Malt, as we fhewed in 
 pur laft Ledture h j, may be employed for the 
 making of Beer, Ale, Vinegar, and Spirit, in 
 all Climates, after the fame Manner as we here 
 yfe Sugar. And the Perfedlion of this Curation 
 would be, to reduce all fuch Robs to an adlual 
 Sugar *, as with fkill might be done, we apprehend, 
 to Advantage. Tho’ as fome Countries and Pa- 
 lates prefer Malt -Liquors and Corn- Spirits, to 
 Wines and the finefl: foreign Brandies, this Art 
 of Sugar-Making need not be univerfally exten- 
 ded to Malt and Grain. 
 
 a) See hereafter XII. 
 h) See Leff, X. Exp* III. 
 
 '18. Many 
 
of Wines and Spirits. 2 < 
 
 20. Many other Ufes are derivable to Arts and 
 natural Philofophy from our prefcnt Experiments 
 but we have only Time to mention one more. 
 
 We fee that Stums, Wines, Vinegars, and in- 
 flammable Spirits of all Sorts, may be commo* 
 dioufly obtained by its Means ; we now add, that 
 the original Matter of them all may be reduced 
 to a brown, thick, treacly, or other coloured 
 Subilance, whether red, yellow, or black, and 
 exported under this difguifed Form to any trad- 
 ing Part of the World, for preparing thefe Com- 
 modities there. And thus the Country poATefled 
 of Sugar, might advantageoufiy fupply many 
 others with Matter for exercifing of feveral Arts *, 
 fuch as the Produdion of Wines, Beers, Vinegars, 
 and Brandies. And in the fame Manner might Fa- 
 milies be fupplied with an artifleial Mull, Stum, or 
 Rob of Grapes, for making any Sort of Wine at 
 home, with much greater Eafe than they now brew 
 Beer : for the expert Artift will eafily give the 
 proper Flavour and Colour of any Wine to 
 this artiflcial Mull, or Rob ; fo that there fhould 
 be nothing more required at home, for the mak- 
 ing it into Wine, than to add the Water and the 
 proper Ferment in the Calk. 
 
 Experiment II. 
 
 ^he common Method of Forcing or Fining down fer- 
 mented vinous LiquorSy fo as to render them expe- 
 ditioujly bright or clear y and fit for Ufe, 
 
 V 
 
 2 1. Wc took an Ounce of fine Iling-Glafs beat Wim 
 with a^Hammer into Shreds, and diflblved it 
 boiling in a Pint of Water, fo that it became a ftiff 
 Geliy when cold. Some of this Geliy we whilked 
 
 a) Sec above, §. \2, and hereafxer Exp, III, 
 
 up 
 
2o8 
 
 Lecture the Eleventh. 
 
 up into a Froth, with a little of the Wine in- 
 tended to be fined ; then ftirred it well among the 
 reft in the Cafk, and bunged it down tight. By 
 this Means the Wine will ufually become bright in 
 eight or ten Days. 
 
 22. This Method is beft fuited to white Wines : 
 but for red ones, the Wine-Coopers commonly 
 ule the Whites of Eggs, beat up to a Froth, and 
 mixed in the fame Manner with the Wines. And 
 thefe are the common Methods of Forcing at pre- 
 fent ufed in the Wine-Bufinefs. 
 
 Rationale. 23- The phyfical Reafon of the Experiment is 
 this, that the Bodies here employed as the Forcing 
 are vifcous or glutinous, fo as to entangle them- 
 felves among the flying Lee, or light Feculencies, 
 that float in the Wine ; and thus forming a Mafs 
 fpecifically heavier than the Wine, fink thro’ the 
 Body thereof, like a Net, carrying down all the 
 Foulnefs they meet with in their Way. But when 
 the Wine is extremely rich, fo that its fpecific 
 Gravity proves greater than that of the Mafs 
 compounded of the as it is called, and 
 
 the Dregs or Lee, this Mafs rifes upwards, and 
 floats on the Top of the Liquor, in v/hich Cafe 
 alfo the Wine will draw off fine. 
 
 Incon^jeni- 24. The principal Inconvenience of this Me- 
 encies of thod of filling Wines is its Slownefs, as not hav- 
 ing its Effedl in lefs than a Week, or fometimes a 
 ° ’ Fortnight, according as the W^eather proves fa- 
 vourable or unfavourable, cloudy or clear, windy 
 or calm ; which appears to be Matter of conftant 
 Obfervation. But the Wine-Merchant frequently 
 requires a Method that fliall with Certainty make 
 his Wines fit for tafliing in a few Hours. And a 
 Method of this Kind there is, but kept as a va- 
 luable Secret in a few Hands. Perhaps it depends 
 upon the prudent Ufe of a tartarized Spirit of 
 \¥ine and the common Forcing, as Acceffories, 
 
 along 
 
Of Wines and Spirits. 209 
 
 along with Gypfum^ or calcined Alabafter, as the 
 Principal ; all which are to be v/ell romaged, or 
 flirred together in the Wine, for'half an Hour, 
 before it is fuffered to reH. 
 
 25. Let it be here obferved that all Wines, Fining mi 
 Malt- Liquors, and Vinegars, which are 
 
 made and perfed in their Kind, will grow fine 
 of themfelves barely by (landing ; fo that if they 
 do not thus grow fine in a reafonable Time, it is 
 a Sign they labour under fome Difeafe, that is, 
 are either too aqueous, too acid, too alkaline, 
 tend to Putrefadlion, or the like. In all thefe 
 Cafes, which may be properly enough called the 
 Difeafes of JVines^ Tuitablc Remedies are required 
 before the Wines will grow fine. 
 
 26. To enquire particularly into the Difeafes Difeafaof 
 of fermented Liquors, with their re fpedlive Cures, 
 
 is not the prefent Defign a ) ; only we mufl ob- 
 ferve, that the moil general Remedy hitherto 
 known for all the Difeafes of Vv^ines, is a pru- 
 dent Life of a tartarized Spirit of Wine, which 
 not only enriches, but difpofes all ordinary Wines 
 to grow fine. But Wines well prepared from ar- 
 tificial Mufl, in the Method above-mentioned, 
 are fubjedl to no Difeafes. And even thofe ob- 
 tained in the common Way may be effedtually fe- 
 cured, againft all Difeafes, by Congelation, which 
 takes away their fuperfluous Water without Pre- 
 judice to their vinous Parts b). 
 
 27. Skimmed Milk likewife is a proper For- FheVfeof 
 cing for all white Wines, Arracks, and fmall Spi- 
 
 rits ; but improper for red Wines, becaufe it dif- 
 charges their Colour. Thus if a few Quarts of 
 well iLimmed Milk be put to a Hogfhead of red 
 Wine, it will foon precipitate the greatefl Part 
 
 See the Appendix to this lecture. 
 
 - b) See below Exp. IV. 
 
 P 
 
 of 
 
2 10 
 
 White 
 
 Wine 
 
 (oloured 
 
 red. 
 
 ^he Ex^e^ 
 
 riment 
 
 improved. 
 
 Lecture the Eleventh. 
 
 of the red Colour, and leave the Liquor n^uch 
 paler, or almoft white. Whence this Experi- 
 ment fometimes becomes of Ufe in turning 
 pricked red Wines into Whites, where a fmali 
 Degree of Acidity is not fo much perceived. And 
 on this Property of Milk depends that other, of 
 Kin thereto, whereby it whitens Wines that have 
 acquired a brown Colour from the Cafk, or by 
 hafty Boiling before they were fermented : For 
 in thefe Cafes, the Addition of a little fkimmed 
 Milk will alfo precipitate the brown Colour, and 
 leave the Wines almoft limpid, or of what they 
 call a Water Whitenefs \ which is much coveted 
 abroad in white Wines as well as in Brandies. 
 
 Experiment III. 
 
 A Method of converting White Wines into Reds ; 
 and of recovering the Colour of decayed red 
 Wmes, 
 
 28. We put four Ounces of what is commonly 
 called Turnjol Rags into an earthen Veftel, and 
 poured upon them a Pint of boiling Water ; then 
 covering the V eftel clofe, and fuffering it to cool, 
 we (trained off the Liquor, which we found of a 
 very deep red Colour, inclining to purple ; fo 
 that a fmali Proportion thereof would give a 
 beautiful bright red, to a large one of white 
 Wine mixed therewith. 
 
 29. For keeping, this Tindlure might be mixed 
 with Brandy, or made into a Syrup with Sugar*, 
 but the ufual Way with the Wine-Coopers and 
 Vintners is to infufe the Rags cold in Wine, for 
 a Night or more, and then wring them with their 
 Hands. The Inconvenience of this Method is, 
 that it gives the Wine a difagreeable Tafte, or 
 what is vulgarly called the 'J'ajle of the Rag: 
 
 whence 
 
2II 
 
 of Wines and Spirits. 
 
 whence the Wines thus coloured ufually pafs 
 among the Judges for prejfed M'^inss^ that have 
 got this Tallc from the Canvas Bags in which 
 the Lees were prefTed. 
 
 30. The Way of infufing the Rags in boiling 
 Water is not attended with this Inconvenience ; 
 but then it loads the Tindure with Water, which 
 may prove prejudicial to the Vv^ine ; or if made 
 into a Syrup, or mixed with Brandy, the Colour 
 is thus diluted, or weakened *, fo that a large 
 Quantity of thefe additional Ingredients comes to 
 be ufed with a fmall one of the Colour, tho’ that 
 alone be the Thing required. 
 
 31. Hence the Bufinefs of colouring Wines red Liconveui- 
 is attended with coniiderable Inconveniencies, in 
 
 thofe Countries that do not afford the tinging 
 Grape^ which yields a Blood -red Juice, and with 
 which the Wines of France are often ftained. In 
 Defed thereof at Oporto they fometimes ufe ' 
 the Juice of Elder-Berries, and fometimes Log- 
 wood, when their Wines are not naturally red 
 enough for this Colour, it feems, they muff 
 have, to make them faleable. 
 
 32. The Colour afforded by our prefent Ex- Remedied. 
 periment is not properly the Port^ but the Bour- 
 deaux-Red^ which does not fo well fuit with Port- 
 
 JVines : Whence the Foreign Coopers are often 
 diftreffed for Want of a proper Colouring to their 
 red Wines in bad Years. We would, therefore, 
 recommend to them the Ufe ot an Extrad made 
 by boiling Stick Laque in Water j which gives a 
 rich Red, that comes tolerably cheap, and is, 
 perhaps, the perfed red Port-Qo\ouv But. if 
 this proves unlatisfadory, let a Method be tried 
 of making a Laque out of the Skins of the ting- 
 
 See hereafter leSi. XIV. Exp, II. 
 
2 12 
 
 Lecture the Elevei^th. 
 
 ing Grape, ox Raifm de "Teinte. Cochineal might 
 likewife anlwer the Purpofe, tho’ it lofes of its 
 Colour by mixing with all acid Wines. Elder- 
 Berries give this Colour in a tolerable Degree, 
 but not without communicating a naufeous 
 Flavour. 
 
 33. The Produce of our prefent Experiment 
 might anfvver well, if the Colour co ild be had 
 pure, or made up into Cakes, without being im- 
 bibed by Rags ; for it is very eafy to obfcure its 
 too great Brightnefs, or vivid purple Brifknefs, 
 by the Addition of a little burnt Sugar, Rob of 
 Sloes, Rob of Oak, Rob of Wine, or any other 
 Colour bordering upon the Tawny, fo as to make 
 a true Port-Coloux. 
 
 Experiment IV. 
 
 A Method of condenfng or concentrating Wines ^ Vine- 
 gars^ and Malt-Liquors^ for Exportation, 
 
 Wines and 34- We took a Quart of ordinary red Port- 
 potable Wine, included in 2iFlorenceE\2Sk^ and placing 
 Liquors Flafk in a Mixture of one Part common Sait 
 T^Fr^ez Snow, or beaten Ice, we found 
 
 the more aqueous Part of the Wine was foon 
 turned to Ice •, from which, by a bare Inclination 
 of the Glafs, the thick, rich, or more vinous 
 Part of the Wine, Vv^as eafily drained. 
 
 FbeExu- 35 - Experiment is here performed too 
 
 rimen/ quick, fo that fome of the thick and valuable 
 regulated, parts of the Wine are catched and detained in 
 the Ice. To perform it in Perfection, the natu- 
 ral freezing Cold fhould be employed •, by which 
 Means, Wines, Vinegars, and Malt-Eiquors may 
 
 be 
 
Of Wines and Sphnfs. 213 
 
 be reduced to a fourth of their ordinary Bulk, 
 without any confiderable Lofs of their eflential 
 Parts ; little more than the ufelefs, or detrimental 
 Water being thus feparated, fo as to leave all 
 the effential Parts of the Wine admirably cured, 
 or capable of remaining perfed, for feveral Years, 
 as has been found upon Trial. And by a prudent 
 Ufe and Application of this Experiment, we con- 
 ceive that great Improvements might be made 
 in the Wine-Trade. 
 
 36. For by a proper Contrivance, and a little 
 Dexterity, which may be eafily gained by Ex- 
 perience, large Quantities of the pooreft Wines 
 might be thus, at little Expence, converted into 
 rich ones, fo as to increafe their Value in Pro- 
 portion to the Diminution of their Bulk. And 
 thus alfo, by repeating the Operation, might ex- 
 tremely rich and generous Wines, ora true Quint- 
 eflence, be procured, for the Amendment of the 
 thinner and poorer Sorts. And in this View it 
 fhould be remembered, that mountainous Wine- 
 Countries are often furnifhed with Snow, by 
 means whereof artificial Freezing might be prac- 
 tifed in the time of Vintage ; the bare intimation 
 of which may give a fufEcient Hint for introduc- 
 ing a new and ufeful Branch of Bufinefs, as Wines 
 may be hence concentrated after Fermentation, 
 no iefs commodioudy than the Juice of the Grape 
 before that Operation a). And if to this be added, 
 that the Art of Congelation is alfo capable of Im- 
 provement from a proper Ufe of Sal-Ammoniac 
 and Water b) ; for, as the Sal-Ammoniac remains 
 eafily recoverable, it fhould feem that little more 
 than a fuitable Apparatus is required to bring this 
 
 a) See LeSi.'K, Exp. III. 
 
 F) See Ua. V. Exp. II. 
 
 F3 
 
 Bufinefs 
 
214- Lecture the Eleventh. 
 
 Bufinefs to Perfeftion, with all defirable Advan- 
 £«ige. 
 
 E X P E R I xM E N T V. 
 
 A Method of recovering 'pricked Wines 
 
 PnclCd TTq a Bottle of prick'd red 7 ^i?r/-Wine 
 
 Tovel 7 d added about half an Ounce of tartarized 
 Spirit of Wine ; then taking the Liquor well 
 together, we fet it by for a few Days, expediing 
 to find it remarkably altered for the better; as 
 upon Trial it appeared indeed to be. 
 
 38. This Experiment depends upon the ufeful 
 Do( 5 lrine of Acids and Alkalies a). All perfeft 
 Wines have naturally fome Acidity ; but when 
 this Acidity prevails too much, the Wine is faid 
 to be prick'd^ which is a State thereof tending to 
 Vinegar h). But the prudent Introdudfion of 
 a fine alkaline Salt^ fuch as that imbibed by 
 Spirit of Wine digefted upon Salt of Tartar, 
 (for fo the tartarized Spirit of Wine is pre" 
 pared) has a direefi; Power of taking off* the Aci- 
 dity; to which Effed: the Spirit of Wine aJfo 
 contributes, and is in other Refpeds a great Pre- 
 servative of fermented Liquors c). And if the 
 Operation be dextroufly performed, prick’d 
 Wines may be thus recovered, and made to 
 remain found and faieable for feme TimxC. The 
 fame Method is likewife applicable to hard Malt- 
 Liquors, or fuch as are but juft turned four, and 
 not near becoming Vinegar. 
 
 ' 39. An Expedient of the fame Nature is fre- 
 
 quently made ufe of to recover four Small-Beer, 
 
 g) See thefe Terms explr.inGcl in the prefixed to 
 
 our L''6iures. 
 
 * b; See LeSl. VII. Exp. II. 
 
 c) See Lcbl. VII. Exp. IV. and the Appendix to the prefent 
 Lcbiure. , 
 
 i .- - •• by 
 
of Wines and Spirits. 215 
 
 by adding thereto a littJe Chalk or Powder of 
 Oyfter-Sheils ; for Chalk and Oyfter-Shells be- 
 ing terreflrial Alkalies, immediately take off the 
 too great Acidity of the Liquor, and caufing 
 an Ebullition therewith, give it a confiderable 
 Briiknefs, if drank before the Ebullition is en- 
 tirely finiihed. In order to continue it the longer, 
 
 ’tis beft to add the Chalk, or Oyfter-Sheils, 
 whole to the Liquor in the Calk ; but Care 
 muft be taken to drink it out foon, otherwife 
 the Liquor will fpoil a). 
 
 Experiment VI. 
 
 A more profitaUe Method., than the common., offer- 
 menting Malt for Diftillation, in order to obtain 
 from it a Brandy, or inflammable Spirit, 
 
 40. We took ten Pounds of Malt reduced to 
 
 a fine Flour, and three Pounds of common for Dipl* 
 Wheat-Meal ; to thefe we added, firft, i^o iation. 
 Gallons of cold Water, and ftirred them very 
 well together ; then five Gallons of Water boil- 
 ing hot, and ftirred all very brifkly again. Let- 
 ting them now ftand for two Hours, we repeated 
 the Stirring again, and when the whole was 
 grown cold, we added to it two Ounces of folid 
 Yeaft, and fet it by in a warmifti Place, loofely 
 covered, to ferment a), 
 
 41. This Experiment exhibits the Dutch Me- 
 thod of preparing the IVaJh, as it is called, for 
 Malt-Spirit, whereby they fave much Trouble, 
 and procure a large Yield of Spirit ; thus com- 
 mocUoufty reducing the two Bufineffes of Brew- 
 
 a) See Le^. VII. tajjtm, 
 
 P 4 
 
 mg 
 
2i6 
 
 Jnd Ad~ 
 ’■vantages. 
 
 Regula- 
 
 tion. 
 
 Lecture the Eleventh. 
 
 ing and Fermenting, to a fingle Operation. In 
 England the Method is, to brev/ and rnafli for 
 Spirit juft as they ordinarily do for Beer ; only 
 inftead of boiling the Wort, they pump it into 
 large Coolers, and afterwards run it into their 
 fermenting Backs, to be there work’d, or fer- 
 mented with Yeaft; thus bellowing twice as much 
 Labour in the Operation, as is required ; and at 
 the fame Time lofing confiderably of their Quan- 
 tity of Spirit, by leaving the grofs Bottoms out 
 of the Still, for Fear of burning. 
 
 42. In the Manner of our prefent Experiment, 
 where the Malt is ground fine, we have all its 
 fermentable Parts fet loofe, fo as at once to mix 
 with the Water. And we can thus put all the 
 Bottoms into the Still, without Danger of burn- 
 ing ; becaufe being rendered fo fine at firft, they 
 entirely lofe their Ciamminefs in the Fermen- 
 tation, fo as to become light or buoyant, and 
 thus increafe the Yield of the Spirit. 
 
 43. The Meal of unmalted Corn is found ne- 
 ceffary to be mixed along with the Malt, to pre- 
 vent its over-fermenting, and throwing off the 
 Matter of the Spirit. But as Difpatch is here par- 
 ticularly required, to avoid Expence and a large 
 Apparatus of VeiTels, a confiderable Qiiantity of 
 Yeaft is added to quicken the Fermentation, fo 
 that it may be finiftied in two or three Days. 
 
 44. More Yeaft ftiould be added if the Wea- 
 ther be cold, and lefs if it be hot *, the Converfe 
 is to be underftood of Meal, more whereof is re- 
 quired in hot Weather to check, and lefs in cold, 
 to haften the Operation ; which in the prqfent 
 Cafe is defigned to be violent, contrary to what 
 ought to be obferved in the Fermentation for 
 Wines, where 'the flower the Operation is per- 
 formed, the better the Liquor will prove. Which 
 
 Rule 
 
. of Wines and Spirits. 217 
 
 Rule may likewife obtain here in a Jefs Degree : 
 for it is polTible to ferment the Wafh fo vio- 
 lently, that it fhall foon end in Putrefadion a). 
 
 And thus by rightly conducing the feveral Parts 
 of the Procefs, we may, by Diltilladon, procure 
 all the Spirit that Malt and Meal are capable of 
 aiTording by Fermentation. The Method of 
 procuring this Spirit will be iliewB in our next 
 JLedure b). 
 
 Axioms and Canons. 
 
 1. We have feen in the preceding Enquiry, 
 that excellent Stums, Sweets, Wines, Vinegars, 
 and Brandies, may be prepared from Sugar, in 
 any Climate, where Water and Tartar can be 
 procured c), 
 
 2. That Malt-Liquors, and Malt-Vinegars, 
 may be commodioudy prepared in any hot Cli- 
 mate, from the Rob or Treacle of Malt ; which 
 is fit for Tranfportation, fo as to convey the de- 
 fired Virtue of the Malt in a fmall Bulk, and 
 retain it perfed; for feveral Years d). 
 
 3. That the Perfedion of the Art of Vinegar- 
 Making depends upon the Converfion of Sugar in- 
 to a fluid Tartar ; or a Method of permanently 
 diffolving a large Proportion of Tartar in Wa- 
 ter e). 
 
 4. That it is pofTible to reduce both Wines and 
 Vinegars to a thick Syrupy Form/) : fince the 
 
 a) Le£i.YU.paJ/im, 
 
 h) See Lea. XII. Exp. I. 
 
 c) See Exp. I. See alfo Lea VII. Exp. I. 
 
 4) Exp. I. See alfo Lea. X. Exp. ill. 
 
 e) See Exp. I. See alfo Lea. VII. Exp. II. 
 
 /) Exp. I, IV. 
 
 original 
 
2i8 Lecture the Eleventh. 
 
 original Matter of them both, viz. Sugar, is 
 folid, and fince they both may be concentrated 
 by Froft to a high Degree of Richnefs and 
 Thicknefs. 
 
 , I 
 
 5. That a new Art may be introduced of fup- 
 plying Foreign Countries with a proper, or rich, 
 fyrupy, or treacly Subftance, which fhall lie in 
 a fmall Compafs, for the making of Wines, 
 Beers, Vinegars, and Spirits, in all Climates, 
 with confiderable Advantage a ) : A Confidera- 
 tion deferving the Attention of the Sugar-Colo- 
 nies, or their Mother-Kingdoms. 
 
 6. That the fweet and tart Juices^ as thofe of 
 Summer-Fruits, Cherries, Grapes, confift of 
 a faccharine and tartareousSubltance; or, to fpeak 
 explicitly, of an adlual Sugar, and an ad:ual fluid 
 Tartar : which affords an ufeful Rule for improv- 
 ing thefe natural Juices in bad Years, and again 
 for imitating them by Art-, as alfo for producing 
 Wines, Vinegars, and Brandies, without them, 
 where Sugar and Tartar can be procured b). 
 
 7. That there is a great Affinity betwixt Su- 
 gar and Tartar, fince they not only refide to- 
 gether, and are intimately mixed in all fweet and 
 tart vegetable Juices, but alfo feem readily con- 
 vertible into each other ; for the acid and tart 
 immature Juices of Plants become faccharine 
 by Ripening; Wine made wholly of Sugar and 
 Water fhoots a large Quantity of Tartar; and 
 Sugar is wholly convertible into Vinegar, which 
 is a fluid Tartar. Whence much Light might be 
 derived for explaining the Nature of Vegetation, 
 Acidity, Sweetnefs, Immaturity, Ripenefs, Vi- 
 
 a) Exp. I, IV. See alfo Lea. X. Exp. III. 
 
 b) Exp. I. See alfo Lea. VII. and X. pajjim. 
 
 nification, 
 
Of Wines and Spirits. 2 i g 
 
 nification, Acedfication, and the Art of procur- 
 ing Tartar a), 
 
 8. That the Improvement, or Perfedlion, of 
 feveral Arts may depend upon a fingie Experi- 
 ment j as we remiarkably fee by our (imple Ex- 
 periment of diiToiving Tartar in Water and Su- 
 gar b ) ; which has a dired: Tendency to improve 
 the feveral Arts of Sweet.s, Stums, Wines, Vi- 
 negars, and Spirits. 
 
 9. That a very large Proportion of Water en- 
 ters the natural Compofition of Stums, Wines, 
 ‘Vinegars, and Spirits c ) ; as plainly appears from 
 hence, that the effen^al Matter of them all is 
 contained in dry Sugar, which being barely dif- 
 folved in Water, and fermented, becomes Wine; 
 or a Liquor that may, by Congelation, be re- 
 duced to a fourth, or a fixth Part of its natural 
 Bulk, without any coniiderable Lofs of its valu- 
 able Part, or of little more than its fuperfluous 
 Phlegm or Water d). 
 
 10. That the Difeafes of Stums, Wines, and 
 Vinegars, are owing to an Over-Proportion of 
 aqueous Parts; fo that if their Water be taken 
 away, without doing Violence to the elTential Mat- 
 ter, thofe feveral Commodities may be preferved 
 in a State of Perfediion ; as we fee they adfually 
 are by Concentration, or Congelation, which thus 
 advantageouflyfeparates their aqueousParts with- 
 out hurting the reft d). 
 
 1 1. That numberlefs new Sorts of Wines and 
 Brandies are producible, barely by adding any 
 well-fcented Vegetables, or their efiential Oils, or a 
 
 Cl) See LeSi. VH. and X. See alfo the prefent Lecture, 
 
 Exp. I. 
 
 ' b) Exp. I. 
 
 c) Exp. 1. and IV. 
 
 J) See Exp. IV. 
 
 Mix 
 
220 
 
 Lecture the Eleventh. 
 
 Mixture of fuch Oils, to a natural or artificial 
 Muft in the Fermentation a). And the fame may 
 be proportionably underftood of the Colours of 
 Wines •, which might, by proper tinging Ingre- ! 
 dients, be thus procured blue, green, yellow, or i 
 of other Colours, if it were neceffary, as well as - 
 pale, or red h), 
 
 12. That the phyfical Agent in the Fining of 
 Wdnes, and other fermented Liquors, is fome 
 proper vifeous Subfiance, which entangles the grofs 
 Particles, and either finks with them to the Bot- 
 tom, or rifes to the Top,^fo as to feparate and 
 keep them feparate from 'the Body of the Li- 
 quor ; and that, on this Foundation, better Me- 
 thods of fining may be difeovered, than thofe 
 liitherto commonly known and pradifed c), 
 
 13. That tartarized Spirit of IVine is a Remedy 
 for acid Wines, and not only abates their Acidity, 
 but alfo ftrengthens, and difpofes them to grow 
 fine, when they are thick and turbid d). 
 
 14. That Milk, deprived of its Cream, will 
 difeharge the Colour of red Wine, by precipitat- 
 ing the tinging Matter to the Bottom ; and fo 
 iikewife leffen, and take off the brown Colour, 
 wherewith white Wines are fometimes acciden- 
 tally tinged e). 
 
 15. That the Bufinefs of colouring red Wines 
 artificially may be improved by a proper Ufe of 
 an artificial Turnfoi without Rags; fuch as an 
 Extra6l of Stick- Laque, &c. but particularly 
 an artificial Tindlure of the Hufk or Skin of the 
 red Grape, or a particular Laque made from the 
 Raijin de Tcinte f ). 
 
 a) Ex^. I. See all'o LeSI. VII. Exp. I. 
 
 h) See Exp. ill. 
 
 <:) Exp. il. 
 
 (i) Exp. Sec alfo the Appendix below. 
 
 e] Exp. II. j) Exp. ill. 
 
 16. That 
 
221 
 
 Of wines' and . Spirits, 
 
 1 6. That it is in the Power of Art greatly to 
 accelerate the Operation of vinous Fermentation, 
 fo as to finifli the whole in a few Days Time : But 
 that this fhould be done only when a Spirit, and 
 not a Wine,' is intended ; becaufe fuch a hafty 
 Fermentation fubverts or dellroys the Texture 
 requifite in vinous Liquors a). 
 
 APPENDIX to Lecture XL 
 Sect. I. 
 
 The Theory of Vinous Fermentation, 
 
 1. The extenfive Do6lrine of Vinous Fermen-= 
 ration being little regarded, in Proportion to its 
 philofophical and pradtical Ufes, it may be pro- 
 per in this Place to lay down its Theory,^ after a 
 concife axiomatical Manner fas we are the better 
 enabled to do from the Labour which Dr. Stahl 
 has bellowed upon this Subjedt b) and fubjoin a 
 few Obfervations with regard to Pradice. 
 
 2. Vinous Fermentation is an inteftine Motion 
 performed by the inllrumental Efficacy of Wa- 
 ter ; fo as to llrike afunder, attenuate, tranfpofe, 
 and again colle6l and recompofe, in a particular 
 Manner, the Salt, Oil, and Earth of a ferment - 
 able Subje<ft c). 
 
 3. Fermentable Subjefls, therefore, are mixed 
 Bodies ; confilling of Salt,^ Oil^ and a Subtile 
 Earth d). 
 
 4. Thefe compound Particles of all ferment- 
 able Subjects are fo fmall, that when afunder 
 they become imperceptible to the Senfes *, for 
 
 a) See Left. VII. pajjhn. See alfo the prefent, Exp. VI. 
 and the following Apt^endix . 
 
 S) See his 'Lymotechnia fundamsr.talis, 
 
 f) Confider all the hjlances, or what feems equipollent to 
 them all. Sugar and Water. ' 
 
 d) Into which ail fermentable Subilanccs are rcfolved by a 
 chemical Analylis. 
 
 neither 
 
222 
 
 Lecture the Eleventh.’ 
 
 neither the Touch nor the Sight diftinguiflies 
 them : Whence being mixed with an aqueous 
 Fluid, they leave it tranfparent. Neither have 
 fermentable Bodies any confiderable Smell or 
 Talfe, befides the Tafte of Sweetnefs. 
 
 5. Thefe Principle.^ of Fermentation, vt 7 .. the 
 Sait, Oil, and Earth, rnuli of Necdlity be in a 
 compound State •, for Separation prduppofes Con- 
 nexion a). And by Compofition is not here un- 
 derltood bare Juxta-pofition, but a very intimate 
 Cohefion of the fmall and different Particles : So 
 that the Salt, Oil, and Earth, in each of thefe 
 little and infenfible Compounds, are in adual 
 Cohefion, Connexion, and Union. 
 
 6. When, therefore, any one of thefe Principles 
 abounds in an Over-Proportion for an intimate 
 Union, the whole Efficacy of the Fermentation is 
 either flopped and impaired, or elfe prefently de- 
 termined. and limited to one certain Species. 
 
 7. And this is to be particularly remarked of 
 the volatile or effential Oil ; which being in an 
 Over- Proportion for an intimate Union with the 
 reft, rather hinders than promotes vinous Fer- 
 mentation, but greatly difpofes the Subjed: to 
 Putrefadion b) 
 
 8. But if the Salt predominates, this does not 
 fo much prevent the Succefs of the Fermentation, 
 provided it be in fome Kind of Connexion with 
 the oily and earthy Principles : And if it be not 
 thus conneded, it is readily taken, by Solution 
 in the Water, from the other duly mixed Por- 
 tion, and thus, in fome Meafure, promotes and 
 affifts the Operation. 
 
 9. This equable Connexion of Salt, Oil, and 
 Earth into a fingle compound Particle, makes a 
 
 a) See above §. 2 . 
 
 0 As in Mace, Cloves, Nutmeg, Uf. 
 
 Corpufcle 
 
of Wines and Spirits. 223 
 
 Corpufcle foluble in Water that is, this com- 
 pound Corpufcic is, by Means of its faline Par- 
 ticle, conneded Vv'ith the aqueous Corpufcles, 
 and moved up and down therewith ; that is, it 
 becomes diffblved therein. 
 
 10. Where thefe compound Corpufcles are not 
 thus conneded with the Water, many of them 
 join together either into a grofs Matter a)^ or in- 
 to a loofe, chaffy, or fpungy one b). 
 
 1 1. When diluted with a little Moifture, thefe 
 compound Corpufcles feel flippery, clammy, and 
 undtuous to the Touch, and after the like Man- 
 ner affedt the Tafle with a ropy Sweetnefs or In- 
 fipidity c), 
 
 12. When undiflurbed. and left to themfelves, 
 they preferve their mutual , Cohefion, and their 
 folid or dry Confidence, without Alteration d), 
 
 13. But as foon as an aqueous Fluid is put to 
 them, there prefently begins a Commotion, and 
 afterwards a fubtile Separation among them. 
 
 14. This Commotion and Separation fird be- 
 gins in the whole Subdance e) ; for before Water 
 is added, the Subjebt may remain in dry, folid, 
 and large Pieces /) ; which being reduced to 
 Powder, each Grain thereof is an Aggregate of 
 many leder compound Corpufcles \ and thefe being 
 put into Water, dinblve and feparateiy float 
 therein, till at Length they become fo dnall as to 
 be invifible, and thicken the Confidence of the 
 Liquor. 
 
 15. When the compound Particles are thus 
 feparated from one another, they are next gra- 
 
 a) As in the Lees of Wine. 
 
 b) As the Grains in Brewing. 
 
 c) As appears in all Inftances. 
 
 d) Confider Malt, Raifins, Sugar, and all the Inftances. 
 
 r) As when Sugar dilTolv^s in Water. 
 
 f) As in Malt, Sugar, ^V. 
 
 dually 
 
224 Lecture the Eleventh. 
 
 dually feparatcd from their own different Parts^ 
 that is, the different Particles whereof they con- 
 fift, viz, the Salt, the Oil, and the Earih, are dif- 
 joined from one another by the Interpofition of 
 the Particles of Water. 
 
 j 6. The firft Commotion is no more than a bare 
 Solution, when the Water lays hold of the faline 
 Parts of the compound Corpufcle, and thus 
 carries them about with itfelf. For of thefe 
 fevreral Principles the faline one fooneft diffolves 
 in Water. 
 
 17. But the fucceeding Separation, viz. xht fer- 
 mentative Motion.^ is a different Thing, and what 
 difentangles the oily and earthy Parts from the 
 faline, partly by the Impulfe of the others in 
 
 ^ their Motion, and partly by the Force of the 
 
 aqueous Particles that are now continually meet- 
 ing and dafhing againfl them. 
 
 18. This Motion is performed by the Water, 
 as a Fluid, or Aggregate of an infinite Number 
 of Particles, in a6lual and perpetual Motion ; 
 their Smallnefs being proportionable to that of 
 the fermenting Corpufcles, and their Motion, or 
 conffant Sufeeptibility of Motion, by Warmth 
 and the Motion of the Air, difpofing them to 
 move other fubtile, moveable Corpufcles alfo. 
 
 19. But more particularly, an aqueous Fluid 
 gives this Commotion, by the certain Agreement 
 of Figure and Size which its Particles have with 
 thofe of the Salt of the fermentable Subjedf : 
 Whence they come to be readily and clofely 
 applied together, fo as to move almoff like one 
 and the famie compound Corpufcle ; whilfl the 
 Water is no way difpofed to cohere immiediate- 
 ly with the Oil or Earth. And thus an un- 
 equal Concuffion is made in the compound Cor- 
 pufdes of the Subject j which Concuffion at 
 
 length 
 
Of Wines and Spirits. 225 
 
 length ftriking cut the faline Particle, and loo- 
 iening the others, brings on a Separation of the 
 original Connexion of the Subjed. 
 
 20. Thus if, inftead of Water, an oily Fluid 
 were poured upon any fermentable Subjedf, no 
 vinous Fermentation would enfue •, as the Oil 
 can neither give a fufficient Impulfe to the com- 
 pound Corpufcles, which are grolTer than it^ 
 own conftituent Particles, nor force away the 
 oily or faline Particles of the Subjedf from the 
 Connexion of the others, which detain, and as 
 it were envelope or defend them, from its Adlion. 
 
 21. Hence an aqiicoiis Fluid alone is the true In- 
 firiment for procuring a fermentable Motion to 
 thefe mixed Corpufjles of the Subjedl. 
 
 22. As the^fmall Parts of this aqueous Fluid 
 are in a perpetual Motion, and by Means there- 
 of affed: the compound Corpufcles of the Sub- 
 jed, a certain Degree of this Motion is required, 
 which principally depends upon external Heat. 
 
 23. It is true, a confiderable Degree of cold 
 will not abfolutely prevent all Fermentation, 
 though it will greatly retard it ; and a boiling 
 Heat will prevent it ftill more. The due Heat 
 therefore for promoting and quickening the Ope- 
 ration, is a tepid one, or the mean betwixt the 
 two Extremes of Freezing and Boiling. 
 
 24. The AdmilTion of the Air alfo, though 
 not of abfolute neceffity, yet greatly promotes 
 and quickens the Adion, as being a capital In- 
 Jlrument in the Moving of oily Particles, and the 
 true Analyfer of oily Subjeds, in Concurrence 
 v/ith the Motion of Fire 
 
 25. But whilfl; the Air thus contributes to 
 haften the Effed, it at the fame Time, by its 
 
 Adivity, 
 
 « See Lect,n. E.rpAW. IV. 
 
 o. 
 
 
 ACt\- 
 
2.26 Lecture the Eleventh. 
 
 A61;ivity, caufes fome remarkable Alterations in 
 the oily Fart •, as being capable not only of mov- 
 ing, bur of ablolutely diffolving and difplacing 
 it trom its original Connexion, and thus carrying 
 it off with itfelf from the whole Mafs a), 
 
 2.6. And hence, though theConfideration of the 
 Air does not in the general fo properly belong to 
 Fermentation, yet it does in particular as having 
 an accidental Power to alter every Species of this 
 Operation : Whence its Agency ought to be well 
 underftood, in order either to procure defireable 
 Alterations in the fermenting Mafs, or to prevent 
 • and corredf fuch as are not eligible. 
 
 27 . The oily Frtnciple.^ which the Air thus fe- 
 parates and diffolves, is alfo elaftic, though it 
 probably has that Property from its Intercourfe 
 with the Air itfelf, added to an extreme Subtility 
 of Farts ; fo that a fmall Bulk thereof containing 
 a large Number of individual Particles, may fill 
 and fatiate a large Bulk of Air h). 
 
 28 . To proceed : When an aqueous Fluid is 
 added to a fermentable Subjedl, expofed to a 
 temperate Heat, and in fome Imall Degree to the 
 open Air, a fermentative Struggle immediately 
 arifes ; the Water by its continual intefline Mo- 
 tion diffolving the faline Part of the compound 
 Particles, and carrying them up and down with 
 itfelf infinite Ways, amidfl innumerable other 
 Particles, as v/ell merely aqueous as fermentable 
 ones : Whence, by this Collifion and Attrition, 
 the oily and earthy Particles are at length fepa- 
 
 a) hs may appear by the Lofs of Spirit and Flavour in open 
 Fermentation, where the Matter is expofed to too much Air. 
 
 b) As in the Atmofpheres of odoriferous Vegetables ; and 
 again in Perfumes or hrong-feented Drugs ; as Mufk, Am- 
 bergreafe, Camphire, AHa-foetida, 
 
 rated 
 
Of IVines and Spirits. 227 
 
 rated and disjoined from their Connexion with 
 the filine. 
 
 29. The oily Particles, as being the moft fub- 
 tile, and moft difpofed tor elaftic Motion^ would 
 thus be thrown up to the Surface of the Liquor, 
 and carried off by the Air, if they were not ’ 
 long involved or enveloped in the earthy ones ; 
 which are not only undifpofed and unfit for Avo* 
 lation, but alfo ftrongly inclined to form larger 
 Colledions or Aggregations with other earthy 
 ones, and fo fink v/ith them to the Bottom d), 
 
 30. But before this can be fully brought 
 about, that is, before many of the earthy Par- 
 ticles are gradually colledled together by their 
 frequent Occurfions, fo as to form a Bulk that 
 can be no longer moved about by the aqueous 
 Fluid, it happens that, by thefe repeated Colli- 
 fions, fbme of the oily Particles (now disjoined 
 from the faline ones, which are ftrongly agitated 
 by the aqueous Particles, and feparated from the 
 earthy ones) are again, by Degrees, more inti- 
 mately connedted with the faline ones ; whilft, 
 on the other Hand, thefe fame faline Particles 
 imbibe and take to themlelves fome of the earthy 
 ones, which being left fingle, upon their Sepa- 
 ration from the oily Particles, floated feparately 
 about in the Fluid h). 
 
 31. And hence proceed the feveral different 
 Confequences of Fermentation •, (i) From 
 
 the Extrication of the faline Particles of the Sub- 
 jedl proceeds the. tart, faline, or acid Tafte of 
 
 d) In the Form of Lees or Sediment. 
 
 V) Obferve that this whole Doctrine is not delivered as hy- 
 pothetical, but as derived from a care.'ul Confideration of all 
 the Infiance both a priori and a pojieriori, in ihe Way of a 
 juft InduSiion, 
 
 (^2 
 
 the 
 
228 
 
 Lecture the Eleventh. 
 
 the Liquor •, which is more fenfible at firft, be- 
 fore the Liquor is duly compofed and fettled, 
 or the new Arrangement and Connexion of the 
 faline Particles witn thofe of the oily and earthy 
 Kinds compleated : After which the Liquor 
 proves milder, fofter, or lefs pungent. ,(2) From 
 the oily Particles being fet at Liberty, proceeds 
 the ftrong Smell of the Liquor, and the Head or 
 the fhining Skin upon the Surface. (3) The earthy 
 Particles colleding together in Clufters, caufe 
 the Fluid firft to appear turbid, and afterwards 
 to precipitate a vifible earthy or clay- like 
 Matter : And fome of thefe earthy Parts in 
 their Motion arriving at the Head or oily Skin on 
 the Surface, caufe it to thicken ; and afterwards 
 carrying it down along with them, thus confti- 
 tute the Lees which abound in Oil. (4) From 
 this Struggle or Collifion, which is produdlive 
 both of Solution and a new Connexion in the fa- 
 line and earthy Corpufcles, proceeds the Ebulli- 
 tion in Fermentation. And laftly, by the fame 
 repeated Collifion of the oily with the aqueous 
 and faline Particlesj the inflammable Spirit is 
 produced a), 
 
 32. Water performs this whole Series of 
 Changes, by becoming the Inftrument and Me- 
 dium of new Separations, Tranfpofitions, and 
 Combinations •, as alfo preferving thefe new Com- 
 binations after they are made, by a Kind of 
 conftant Interpofition, or elTential Concurrence b). 
 For Wine cannot, without extreme Alteration, 
 be deprived of all its Humidity ^ though it may 
 be freed from the fuperfluous Part thereof by 
 Congelation, without the leafl Prejudice r). 
 
 «) See Led. VFl. Exp. IV. 
 
 b) Sec Led XI. Exp IV. 
 
 c) This appears to be true in Faft. 
 
 33. And 
 
Of Wines and Spirits. 229 
 
 33. And although the aqueous Humidity were 
 intirely taken away, yet the fermented Matters 
 would ftill retain and refpedlively fhew the Al- 
 teration brought upon them ; dor the vSpirit, 
 with its eflential Aquofity, would appear in one 
 Place, the acid Salt in another, 'and the dry 
 Earth, or unduous F^ces^ in a third a) : And 
 in the two laft the aqueous Part may be totally 
 feparated, without any way altering the Places 
 or State they were put into by the Adt of Fer- 
 mentation b). 
 
 Sect. II. 
 
 FraEHcal Ohfervations relating to vinous Fermen- 
 tation, 
 
 I. According to the Dodlrine above deliver- 
 ed, every fermentable Subjedl is in itfelf, or 
 may be reduced to, a dry and folid Body, con- 
 fiding of oily, faiine, and earthy Parts, fo put 
 together as perfedlly to diffoive with Water in- 
 to a tranfparent clammy Liquor : Whence Malt 
 or other Grain, Grapes or other Fruit, are to 
 have their proper fermentable Farts edimated 
 by the Quantity of dry, pure, fermentable 
 Matter, or Sugar, they would yield ; all their 
 other Parts being either chaffy or aqueous, 
 and foreign to the real Purpofe of Fermen- 
 tation. 
 
 2 This teaches us a Rule for reducins; all 
 fermentable Matters to their lead Dimenfions, 
 and preferving them at all Times fit and perfcdl 
 for Ufe ; viz. by making them into pure dry 
 Sugars : Which, though at prefent generally 
 
 a) As we fee in Tartar, and dry Wine Lees. 
 
 h) See LcSi. VII. pajjtm. , 
 
 0.3 
 
 pradlifed 
 
230 
 
 Lecture the Eleventh. 
 
 pra6Ufed upon the Sugar-Cane only, is per- 
 formable to good Advantage upon other Sub- 
 je(^ts a). 
 
 3. The Perfedlion of Fermentation in general 
 depends upon three Things ^ vix. (i.) the Good- 
 nefs and Suitablenefs of the Subject; (2.) the 
 Goodnefs and Proportion of the Water put to it \ 
 and (3.) the Regulation of the Operation. 
 
 X The Goodnefs of the Subjeft in general is 
 determined by its Purity and perfect Solubility 
 in vVater, without impairing the Tranfparency 
 thereol, or changing its Colour. And this Cha- 
 rader is excellently anfwered by the findl Su- 
 gar ”, though the ufual Manner of preparing 
 and rehning it, by a ftrong Heat, fomewhat 
 indifpofes it for a ready Fermentation, which 
 newly exprefled and unboiled vegetable Juices arc 
 greatly difpoled to ^ whence their Fermentation 
 is much fooner finifhed. 
 
 5. T hat V/ater is generally allowed befl: for 
 Fermentation, which of itfelf contains raofl' fer- 
 mentable Parts ; and fuch is, (i.) the Water that 
 naturally grows along with Fruits ; (2.) Rain 
 Water, Vv'hich is impregnated with vegetable 
 Matters; and (3.) River- Water, which ailb con- 
 tains fome vegetable Subftances ; but (4.) Spring 
 Water is the purefl; and lead: altered by foreign 
 Mixture : Whence the trued Edimate may be 
 rnade of a fermentable Subjed by its Means, pro- 
 vided it have no Peculiarity contrary to the Na- 
 ture of Fermentation b). 
 
 6 . The Qiiantity or Proportion of the Water 
 is limited by the Nature of the Thing. We fee 
 that dry fermentable Subjects will never of them- 
 
 ‘ fclvcs fall into Fermentation ; too little Moidure 
 
 <?) See Le^. VI i. Exp. I. and Lc^. X. Exp. III. 
 
 h) SeeZrJ?. V. Vll.andX. 
 
 difpofes 
 
Of TVtnes and Spirits, 231 
 
 difpofes them rather to putrify than ferment ^ ; 
 and too large a Proportion fcatters and diifufes 
 them, fo that the Parts have not their Effedt upon 
 each other, and become in a Manner loft : So 
 that there is a certain middle Proportion which 
 is beft, and fuffers the Whole to ferment freely, 
 and to obtain fuch a Body and Confidence as 
 will enable it to keep found and perfed *, and 
 this Proportion is about two thirds or three 
 fourths of Water to one of perfedly pure and 
 dry fermentable Matter. 
 
 7. The Regulation of the Operation includes, 
 
 ( I ) the Manner of putting the Subjecl to work j 
 and (2) the external Regimen during the Ope- 
 ration. The Subjed may be fet to work either 
 with or without Addition, and with or without 
 Heating ; and this according to the Climate or 
 Seafon of the Year. The recent exprelTed Juice 
 of Grapes feldorn requires either *, but falls im- 
 mediately to ferment of itfelf, and finifhes the 
 Work in a few Days. But in cold Countries all 
 fermentable Juices require to be quickened by 
 artificial Warmth, and the Addition of a proper 
 Ferment. The Heat fhould be barely tepid, 
 and the Quantity of Ferment moderate •, fo as 
 to begin the Operation fpecdily, before the Li- 
 quor receives any Damage from the external Air, 
 or Change of Weather. The Ferment employed 
 muff be of the fame Nature with the Liquor, or 
 yielded by a fermenting Subftance of the fame 
 Kind ; otherwife it will introduce and imprefs 
 its own foreign Nature upon the Subjed. 
 
 8. Ferments are thofe Subftances which added 
 to a Liquor prepared for Fermentation, make 
 it begin and end the Operation fooner than it 
 Vvould have done by itfelf. They confift of 
 
 ^ See Lea, YU. 
 
 0^4 the 
 
232 Lecture the Eleventh, 
 
 the mod fiibtile, moveable Parts of the ferment- 
 ing Liquor, already feparated irom the grolTer 
 or more fluggifli ; and are therefore thrown up 
 to the Top of a fermenting Liquor : Vv^ience 
 being taken in their State ol fermenting Motion, 
 and added to a frefli Parcel of prepared Liquor, 
 no wonder if they foon fet it alfo in a ferment- 
 ing Motion. But Care mud be had not to ufe 
 an Over-Proportion, left inftead of quickening 
 the Operation, it fhould be perverted by too 
 great a Confufion and Diforder ; which if it 
 fhould happen, can not eafily be ftopped, nor its 
 Inconveniences be eafily remedied. 
 
 9. The external Regimen during the Opera- 
 tion regards the Admiffion or Exciudon of the 
 Air, and the Warmth of the Place. The free 
 Admifiion of the Air greatly promotes and 
 quickens the Operation, but carries away fome 
 of the fine, volatile, un6tuous Parts of the Sub- 
 ject:, and confequentiy impoveridies the Liquor : 
 whence the mod: perfect Way is to exclude 
 the Air, and to perform the Operation in a 
 ciofe CadK, if Expedition be not required. In 
 this Cafe, a little Space fhould be left unpofief- 
 fed by the Liquor at the Top of the Vefiel, and 
 then there will be no Dan'^er of burfting it. 
 indeed this might otherwile be readily pre- 
 vented, by the Ufe of a Valve to Jet out the 
 foul Air, v/hich is conllantiy generated in Fer- 
 mentation, and if too long detained in the Cafic, 
 is apt to be imbibed again by the Liquor, fo as 
 to give it a naufeous Tafte and Odour. And 
 if the Climate or Seafon be cold, the Place of 
 the Operation fiiould be kept moderately warm 
 by Fire, or fome proper Contrivance ; otherwife 
 the Fermentation may languifh, or be checked, 
 before the full Effecfl is procured. 
 
 10. Thefc Cautions being duly cbferved, 
 
 the 
 
Of Wines and Spirits* 233 
 
 the Operation will be performed to great Ad- 
 vantage. When it is fully ended, or rather a 
 little before, the containing Veflel muft be 
 clofe flopped up, and kept well fecured from 
 the external Air, that the Liquor may, of it- 
 felf, grow perfectly bright and fine ; as it will 
 do, if no Error has happened in the Manage- 
 ment, And this is the mcfl perfect Method of 
 fermenting Wines, v/here the fermentable Li- 
 quor is prepared by Art a) j but other Cautions 
 and Rules are required, when Nature affords 
 the Juice imperfect, or unduly mixed, as in 
 bad Vintages, &c. b), 
 
 11. Bur this Method of fermenting clofe is 
 fomewhat flow ; and greater Expedition is often 
 required in Practice, infomuch as fometimes to 
 become the primary Confideration. We fliall 
 therefore next take a View of the feveral artifi- 
 cial Means to be ufed for fhortening the Opera- 
 tion, without any confiderable Prejudice to the 
 Liquor. 
 
 12. The Things that have a principal Tenden- 
 cy to haflen the Bufinefs of Fermentation, are, 
 
 (1) the making of the Liquor fufficientiy dilute-, 
 
 (2) the Addition of a large Proportion of Fer- 
 ment ; (3) the keeping the Whole in a due De- 
 gree of Warmth j and (4) the free Admilfion of 
 the external Air. 
 
 13. ’Tis a common Obfervation, that thin 
 Wines finifh their Fermentation fooner than fuch 
 as are rich ; as if, for the Sake of Difpatch, they 
 fhoiild be made a little thinner than ufual. The 
 Defect may be afterwards fupplied with Spirit of 
 Wine, and richer Wine, according to the Prac- 
 tice in Wine-Countries when the Vintage proves 
 poor and watery r). 
 
 a) See Lea. VII. Exp, I. & Le3. XI. Exp. I. 
 
 See Zrijj?, VIL & 'k.\,pa£im, c) See Lea. XI. Exp,\V . 
 
 14. A 
 
231 - 
 
 Lecture THE Eleventh.. 
 
 14. A large Proportion of Ferment has a 
 great r*0'A^er to lorward the Operation, and be- 
 comes necelTary in making all the artificial Wines, 
 Vt'heie the vegetable juice is not recent, or 
 where it has felt the Force of the Firej unlefs 
 the Wine be purpolely defigned to ferment im- 
 pel fedtly, that it may retain its Sweetnefs, and 
 appear the richer : but this is always with a 
 Lofs of Strength or Spirit, which, however, may 
 readily be fupplied by the Help of Brandy. 
 
 14. Where the utmoft Expedition is required, 
 a due Temperature, or tepid Degree of external 
 Warmth, imifl:, by all Means, be kept up by 
 Art, if the Climate or Country does not natu- 
 rally afford it : For Heat has a peculiar Power of 
 liquifying and thinning all Fermentable Juices, fo 
 as to make them work, without lelTening their 
 Strength as diluting does ; which indeed it rather 
 increafes, if it be not too violent, or too long 
 continued. 
 
 16. We have already ohferved, that too free 
 an Admifiion of the external Air, though it great- 
 ly forwards the Operation, yet confiderably pre- 
 judices the Liquor, by carrying off its finer and 
 more fpirituous Part. The free Air, therefore, 
 is to be admitted prudently, and principally at 
 firft, in order to excite the fermentative Motion ; 
 and this fpirituous Part may be afterwards de- 
 tained, or kept from flying off, towards the 
 End of the Operation, by covering the Veflfel 
 clofc, or giving it but little V ent And when thefe 
 feveral Means are prudently ufed together, the 
 Operation may be performed with confiderable 
 Expedition and Advantage; provided the original 
 fermentabie Matter be rightly difpofed, or duly 
 mixed of faline or acid, oily, and terrcflrial Parts. 
 
 17. The Phenomena of vinous Fermentation , 
 are various, and differ according to the Degree 
 
 of 
 
of Wines and Spirits. 235 
 
 of the Operation ; though the ultimate E-ffe6l is 
 generally the fame. Sometimes the Fermenta- 
 tion gives manifeft Signs of itfelf ; as by Froth- 
 ing, HilTing, Explofion, &c. and fomeiimes 
 again fcarce any manifeft Signs at all •, whence 
 we may confider it as an apparent or latent Ope* 
 ration. The apparent is fufficiently known by its 
 Signs •, but the latent has been lefs regarded. 
 
 18. When any fermentable Matter is fufficient- 
 ly diluted with Water, it has immediately a na- 
 tural Tendency to Fermentation , and hath of- 
 ten aiftually fermented and produced a Wine, 
 though a Spectator could neither fee, nor well fu- 
 fpeeft, any fermenting Motion in the Liquor. In 
 this Cafe, where no Ferment has been ufed, and 
 the Operation proceeds in its own natural, flow, 
 and filent Manner, there may be commonly feen 
 on the Surface a thin, IhiningSkin; which, in- 
 ftead of a large, frothy Head in the ftronger Fer- 
 mentation, keeps in the fine Parts, and prevents 
 their Avolation and Efcape. Sometimes alfo a 
 Degree of Hoarinefs, Finew, or Mouldinefs, 
 will appear on the Top, without mixing itfelf 
 with the Body of the Liquor, or without com- 
 municating any ill Tafte thereto. And in this 
 Manner a flow and filent Fermentation has been 
 carried on for feveral Months, without any fpirt- 
 ing up of Bubbles, or other common Signs of 
 the Operation ; though it has, at laft, finiffied 
 its Courfe to greater PerfeCcion, 
 
 19. And fomething like this filent Fermentation 
 remains for a long Time in the Liquor, after 
 the common tumultuary Fermentation is finiffied, 
 which indeed leaves its Work but imperfed: ; 
 fo that the Liquor afterwards requires a confi- 
 derable Time to grow fine, ripen, and become 
 fit for Drinking : Whereas in the filent Me- 
 thod 
 
236 Lecture the Eleventh. 
 
 thod, thefe Ends are all at once carrying on 
 at the Time of the Operation. And here lies 
 a great Part of the Advantage which the (low 
 Way of fermenting clofe has over the com- 
 mon one. 
 
 20. It is obfervable, that though a fmall 
 Quantity of Liquor finilhes its Fermentation 
 fooner than a large one, yet the larger proves 
 
 > the better ; as a great Body of Liquor is not fo 
 liable to receive pernicious Alterations, from 
 Heat, Cold, the Air, or other accidental Things. 
 And even where nothing remarkable of this Kind 
 has happened, it is furprizing to note the Diffe- 
 rence betwixt a fmall Quantity and a large one, 
 of the very fame Liquor, fermented in the very 
 fame Manner, only the one in a fmall and the 
 other in a large Veffel. 
 
 21. Small Wines may be brought to undergo 
 a fecond Fermentation, by being mixed with 
 proper fermentable Materials ; and thus may 
 be rendered ftronger and richer, fo as to be fit 
 for Exportation, Cfc. Otherwife it is obferved 
 that Wines which finifli their Fermentation in 
 eight or ten Days, will not ordinarily endure 
 the Sea. 
 
 22. It is a neceffary Caution in all Fermenta- 
 tion, to prevent too great external Heat, for Fear 
 of changing the Fermentation to Putrefadlion 
 and to remove the Wines to a cooler Place, when 
 the Violence of the Operation is over ; that they 
 may purge and fine themielves by Degrees, with- 
 out Danger of turning acid, as they are apt to 
 do in a hot Place. Or if they cannot be kept 
 cool, they ought to be early racked from their 
 Lees ; which tends to preferve them found, and 
 prevents their turning eager, ropy, and foul a). 
 
 23. It 
 
 ■) See Lect, VII. 
 
of Wines and Spirits. 237 
 
 23. It is to be obferved of all Liquors pre- 
 pared by Fermentation, that the Interpofition of 
 Water keeps not only the faline, oily, and fpiri- 
 tuous Parts, but alfo the mucilaginous and earthy 
 ones, in their due Arrangement and fome Degree 
 of Connexion ; from which if they are again dif- 
 turbed, there happens fuch a Change as cannot 
 well be prevented from proving pernicious, but 
 the Liquor will fuccelhvely and haftily proceed 
 on to Corruption a'). Thus if a fermented Li- 
 quor be agitated by a great boiling Heat, its 
 proper Arrangement is thereby difordered, and 
 the Liquor not only becomes manifeftly thick 
 and turbid, but more faline and auflere, through 
 the Separation of the fpirituous and oily Particles 
 from the faline ones, wherewith, being before in 
 fome Meafure connedled, their Acrimony was 
 (heathed or abated. 
 
 24. Such Liquors tend fo much the fafler to 
 Alteration or Putrefaction, if they are not care- 
 fully looked after and preferved ; but efpecially 
 if, through any great Commotion by Heat, the 
 more intimate Connexion of the fpirituous Parts 
 with the faline and mucilaginous, or even with 
 the remaining aqueous ones, be difturbed and 
 broken : Whence either the whole Mafs turns 
 to Vinegar, or to a ropy, corrupt, putrid Sub- 
 fiance a). But if fuch fermented Liquors arc 
 carefully preferved at Reft, and kept from Inju- 
 ries, they will long remain in a found and un- 
 corrupted State ; as we continually fee in Wines 
 and Malt-Liquors. 
 
 2 5. And farther, all thefe fermented Liquors will 
 be fitted to refift the Alterations of the Weather or 
 
 a) See VII. 
 
 Seafons 
 
238 ■ Lecture the Eleventh. 
 
 Seafons of the Year, with refpeft to Heat, Cold, 
 and a fermenting Humidity in the Air, (which is 
 by fome efleeined the Caufe of Fretting in Wines) 
 if their fuperfluous Water be artificially feparat- 
 cd from them, fo as that the Liquor itfclf may 
 be concentrated *, in which State it will remain 
 for many Years unchangeable, through the Sum- 
 mer’s Heat, and the Winter’s Cold 
 
 26. When a chemical Anaiyfis is made of thefe 
 Liquors, the firft Part that rifes is inflammabk 
 Sprit \ the next, Phlegm^ mixed with an Acid, 
 and an efifential Oil, leaving a thick Matter, or 
 Rob of Wine, at the Bottom ; which, when 
 freed from its fuperfluous Moifture, is obferved 
 to be very durable, and full of Tartar. But the 
 bare Mixing of thefe feveral Parts together will 
 not make the original Liquor again : Which 
 fliews that they were all before connetled in a 
 certain particular Manner, which was diflblved 
 and defcroyed in the Adi of Separation ; and 
 again, that each of thefe Produdlions received a 
 particular new Kind of Alteration from that A6l 
 of Separation, which will not fuffer them to reu- 
 idte as before, without fome proper intermediate 
 Subfiance, or a new Fermentation. 
 
 27. Hence pure Wine confifis of much Wa- 
 ter, a moderate Quantity of inflammable Spirit, 
 a little efiential Oil, a Proportion of acid Salt, 
 and a certain mixed Subftance, or P^ob^ called 
 by Becher^ the media Subfiantia Vini, And whilfl 
 thefe feveral Parts remain firmly united together 
 in their due Proportion, the Wine is in its per- 
 fedc State : But as their Connexion proves loofe, 
 or any one of them becomes deficient, or abounds 
 in an Over -Proportion, then the Wine is faulty, 
 
 * See Lict. XI. Exp, IV. 
 
 and 
 
239 
 
 Of Wines and Spirits. 
 
 and expofed to Injuries and Alterations for the 
 .worfe: And this fhews us, the true Foundation 
 of what may be called the Health or Hifeafes 
 of PHines. 
 
 28. That a large Proportion of Water necef- 
 farily enters the Compofition of Wine, appears 
 plainly by its- artificial Preparation a) \ and 
 again from the Congelation of the natural h). 
 But though this large Qiiantity of Water is re- 
 quifite in the Fermentation, and ferves to carry 
 it on the better ; yet it is not afterwards effential 
 ^to the Wine, but rather foreign and detrimental, 
 ^expofing and fubjeding it to Changes, which it 
 would not otherwife undergo : Whence the fo- 
 vereign Remedy for all Wines, is to deprive them 
 of their fuperfiuous Water, in order to render 
 them perfedt and unchangeable, without fome 
 uncommon and extraordinary Violence or Ac- 
 cident. And indeed this Remedy is fo effec- 
 tual as to make all others unneceffary ; infomuch 
 that the pooreft and thinned: Wines may, by its 
 Means, be rendered perfedly durable, and full 
 bodied h), 
 
 29. But as there may be fome Difficulty in the 
 particular Ufe of this grand Remedy fin the large 
 Way of Bufinefs) the next Expedient is, to ufe 
 highly rectified and pure Spirit of Wine, in fuch 
 Proportion as to prevent all Change for the worfe, 
 and preferve the eifential Parts of the Wine, as it 
 were by a Balfam. But when the Cafe is very 
 bad, this Remedy ^of itfelf will fcarce prove 
 fufficient, unlefs affifled by fomewhat to give 
 a Body as that gives Strength. Whence it is 
 highly convenient to have always at Eland a 
 
 a) See Lect. VII, Exp. I. 
 
 if) See Lect. XI. Exp. IV. 
 
 Quan- 
 
240 Lecture the Eleventh, 
 
 Quantity of Wine made as rich as ever it will 
 ferment ; a fu table Proportion whereof being 
 added along with the Spirit, will have a very 
 good Effedt ; efpecially if the Whole be quicken- 
 ed with a little ejfential Oil of Wine^ which, in the 
 Cafe of over-aqueous Wines, is generally defi- 
 cient. And this being a capital Difeafe in Wines, 
 or that to which moil of the reft are originally 
 owing, it may be proper here to give a Form of 
 a Remedy which has been found effectual for 
 the Purpofe. 
 
 30. Take an Ounce of fine eflential Oil of 
 Wine, mix and grind it with a Pound of 
 dry Loaf-Sugar into an El^eofaccharum ; 
 diffolve this EUoJaccharum in two Gallons 
 of the richeft Wine ; and add to it two 
 Gallons of the fineft Spirit of Wine, fo 
 as that they may be well incorporated to- 
 gether. The Dofe of this Mixture muft 
 be proportioned to the Exigence •, but in 
 ordinary Cafes one half will fuffice for a 
 Pipe of Wine. 
 
 31. There is a Difeafe of Wines oppofite to the 
 former, and that is when too much of their aque- 
 ous Moifture is drawn from them, whence they be- 
 come dry and parched, as it were, for Want of it. 
 This Cafe indeed cannot well happen, except by 
 the Method of Condenfation ; whereby Wines 
 may have their effential Parts brought fo clofe 
 together, as to become unfit for Drinking till 
 fet more 'afunder, and diluted. But this muft 
 not be attempted with Water alone, for Fear of 
 inducing a Flatnefs. The beft Way is, to have a 
 dilute or thin taftelefs Wine ready at Hand for 
 
 the 
 
2AI 
 
 of Wines and Spirits. 
 
 the Purpofe a ) ; whereby any Degree of Small- 
 nefs may be given at Pleafure. 
 
 32. But the artificial Method of preparing 
 Wines renders all Remedies unneceflary, as it 
 intirely prevents their Difeafes ; fo that they need 
 not be made either too aqueous, or too dry, but 
 cohftantly of a perfed full Body, and therefore 
 not fubjedt either to Acidity, Ropinefs, orFoul- 
 nefs, when once well cleared of their grofs Lees, 
 in the ordinary Way of Racking. 
 
 33. But in Cafe the Wine fhould not foon 
 grov/ fine of itfelf, the Addition of a little tar- 
 tarized Spirit of Wine will haften the Effe6l h) : 
 Or, to make at once a general Remedy for Wines 
 that are too poor and aqueous, or will not tho- 
 roughly fine themfelves ; let a pure, taftelefs, " 
 and totally inflammable Spirit be made from Su- 
 gar *, digeft this Spirit upon a tenth Part of pure 
 and dry Salt of Tartar for three Days; decant 
 the Liquor, and put it to ten Times its own 
 Quantity of a Wine made as rich as it pofTibly 
 would ferment': Of this Preparation fix or eight 
 Quarts will at any Time mend, improve, and 
 fine down a Pipe of ordinary Wine. 
 
 <*) See Le^. VII. Exp, I. 
 
 1) See Ua. XI. Exp. II. IV. 
 
 R 
 
 LEC- 
 
[ 242 ] 
 
 LECTURE XIL 
 
 CONTAINING 
 
 Attempts to illiijlrate and improve the Arts 
 depending upon Distillation. 
 viz, Mdlt* Stilling, Redtifying, and Com- 
 pounding. 
 
 fheSuh- I. TJ'AVING already gone through the Arts 
 jr I depending immediately upon vegetable 
 Fermentation^ we next proceed to con- 
 fider the Ways of improving the Art of DF 
 fiillation^ which depends thereupon feconda- 
 rily. 
 
 Dljiilla- 2. The Word Diftillation is here ufed in the 
 iion,mjhat, popular Senfe, to fignify the Art by which all 
 inflammable Spirits, Brandies, Rums, Arracks, 
 and the like, are procured from vegetable Sub- 
 jedbs, by the Means of a previous Fermentation, 
 and a fubfequent Treatment of the fermented Li- 
 quor by the Alembic, or Hot-Still, with its pro- 
 per Worm and Refrigeratory. 
 
 7he Arts Yhe Arts therefore at prefent to be con- 
 
 are thofe of Malt-Stilling, Redtifying, 
 ^ " * and 
 
Of Dif illation. 243 
 
 and Compounding, with the Bufinefs of the Brai;i- 
 dy-Merchant, the Officers of Cuitoms and Ex- 
 cife fo far as relates to Spirits, and of the feveral 
 Dealers in Brandies, Rums, Arracks, and Cor- 
 dial Waters. 
 
 4. The Experiments we ffiall exhibit will ffiew, 
 
 (i.) the Method of Diftilling a Spirit from a fer- 
 mented Malt- Wort, commonly called JVafb., in 
 order to obtain Jqua or the ordinary Malt 
 Spirit, of which many Cordial Waters are made 
 by the Compounders, Apothecaries, and others : 
 
 (2.) Our fecond Experiment will exhibit the Me- 
 thod O'" purifying or redifying this Spirit of the 
 firft Running, or, Low-Wines^ as they are called, 
 into a faleable Proof- Spirit, or what they em- 
 phatically call Proof Goods that is, a certain 
 ftandard Spirit, ufually confilting of one half 
 Water and the other half Alcohol : (3. J Our third 
 Experiment will exhibit the i\rt of the rectifying 
 Diftiller, or the Method whereby the Proof 
 Goods of the Malt-Sciller are made into a fweeter 
 or cleaner Spirit, for the finer Ufes of the Com- 
 pounder and Apothecary : (4.) Ouv fourth Ex- 
 periment will fhew the true Method of examin- 
 ing Proof in Spirits, and difeover the Invalidity 
 of the common Methods of judging of the Pu- 
 rity, Genuinenefs, and Goodnefs of Brandies, 
 
 Rums, and Arracks : And (5. j our fifth Expe- 
 riment, will ffiew the Method of making Cordial 
 or Compound Waters in Perfection. 
 
 R 2 
 
 E XP E R I- 
 
244 - 
 
 Lecture THE Twelfth. 
 
 •The Dipl 
 
 lation of 
 Wajh. 
 
 Wims. 
 
 The Expe-‘ 
 riment ex- 
 tended » 
 
 Experiment I. 
 
 ^he Method of diftilling Malt-Waflo^ or a fermented 
 Mixture of Meal and Malt^ for Spirit. 
 
 5. We brifkly ftirred together the Malt-Wafli j 
 prepared in the laft Experiment of our laft Lee- 
 ,ture^ and therewith filled two thirds of a btill, , 
 firft made hot and dewy on the Infide with boil- 
 ing Water, and kept the whole Stirring till it al- 
 moft begun to boil *, then we immediately clapp- 
 ed on the Head, and luted it down. There now 
 foon ran, in a flender Stream, from the Nofe of 
 the Worm, a fpirituous Liquor that was in- I 
 flammable, or burnt in the Fire. We continued i 
 to work fo long as the Liquor that came over 
 would, when thrown upon the hot Still -Head, 
 catch Flame from a lighted Candle applied to 
 the rifing Fume. 
 
 6. And thus we obtained what the Malt-Stil 
 lers call a Malt Low-JVine \ that is, a fpirituous 
 Liquor from fermented Malt and Meal, fo di- 
 luted with Phlegm or Water, as that the laft 
 Runnings of it would not burn upon the Still- 
 Head. That which comes over after the Spirit 
 falls off from being Proof, till it will no longer 
 burn on the Still-Head, is called by the Name 
 of Faints 
 
 7. This Experiment may be rendered gene- 
 ral, by a flight Variation of Circumftances ♦, that 
 is, it may be made to ferve as an Inftance of all 
 the Ways of procuring inflammable Spirits, 
 whether Brandies, Rums, Arracks, Cyder- Spirit, 
 or the like : F"or if any Wine, Beer, or fermented 
 
 Liquor 
 
Of Dtf illation: 245 
 
 Liquor from Sugar, Treacle, Roots, Fruits, 
 be treated in the fame Manner, it will afford a 
 Spirit differing only according to the Nature, or 
 fpccific Tafte and Odour, of the Subjed. 
 
 8. But none of thefe Subjcds will afford the 
 leafl drop of inflammable Spirit without a pre- 
 vious Fermentation a). Thus though the recent 
 Juice of the Grape, or any other fermentable 
 Juice, were diftilled to Drinefs, yet no inflamm- 
 able Spirit would be procured : Whence it ap- 
 pears that inflammable Spirit is a Thing pro- 
 duced by Fermentation b), 
 
 9. The Cautions required to render the Ex- Cautions, 
 periment fuccefsful, and the Produdion perfed, 
 
 are, (i.) That the Fermentation be well per- 
 formed, and the Liquor become truly vinous, 
 and of an acid Pungency c) ; (2.) that it be gently 
 diftilled, by Means of a foft, well regulated, 
 
 Fire ; (3.) that the groffer Oil, apt to rife along 
 with the Spirit, be kept back by a proper Strain- 
 er, or thick doubled Flannel, laid under the Nofc 
 of the Worm. If thefe Cautions be duly ob- 
 ferved, the Low-Wines will prove conflderably 
 pure and vinous. 
 
 10. When all the Spirit is thus obtained there Manage- 
 remains behind in the Still what they commonly ntent, 
 call Bottoms ; that is, the grofs Parts of the 
 fermented Meal and Malt mixed with Water. 
 
 This grofs Matter is generally ufed for the 
 Feeding of Hogs •, whence the Malt-Stillers 
 
 See Lea, VII. Exp. IV. 
 
 h) See Lea. XI. pajjim. 
 
 f) See Lea, VII. and XI. 
 
 .R 3 
 
 Malt- 
 
2 4-6 Lecture the Twelfth. 
 
 of England are commonly large Dealers in Hogs : 
 But in Holland that makes a leparate Bufmefs. 
 
 II. Thus Vv^e have gone through three of the 
 principal Branches of Malt Stilling *, viz. the 
 Brewing, Fermenting, and firft Diftilling Parts ; 
 or the Making of the Wort, the Working it in 
 the fermenting Back, and the difliiling it from 
 the Walh a). There is but one Part more of 
 this Art, viz. the Redifying Part ; or the Way 
 of making up their Goods as they call it, to fale- 
 able Proof : And how this is performed will be 
 feen by the following Experiment. 
 
 Experiment II. 
 
 ^he Method of fimple EeEHfication^ or Bijlilling the 
 LoW‘Wines.^ produced by the foregoing Experi- 
 ment^ into Proof-Spirit for Sale. 
 
 Proof-Si>i- 12. We took the Low-Wines produced in 
 rU. the preceding Experiment, and diftilled them 
 over- again in Balneo MarH., or barely by the 
 Heat of boiling Water ; and thus we obtained 
 a purer and higher redified Spirit than before, 
 v/hich being let down with fair Water to a cer- 
 tain Size or Standard called Proof h , is what 
 the Malt-Stillers underftandby Proof-Goods, or 
 their redihed Malt-Spirit. 
 
 »?) See I.eB. XI. Ex^. VI. 
 
 b) V/hat this Proof is, fee explained in the fourth Experi- 
 ment of the prefent Ledure. 
 
 13. The 
 
of Dif illation. 247 
 
 13. The common Malt-Stillers indeed do not 
 thus redlify their Spirit in Balneo Maria^ but 
 barely rediftill their Low-Wines in a fmaller 
 Still ; fo that their Spirit is not fo clean as that 
 of our prefent Procefs. The Perfedion there- 
 fore of the Art of Diftilling from Malt feems 
 to require a good Method of redifying clean, 
 as well as a careful Obfervance of the Cautions 
 above laid down a), 
 
 14. Having thus regularly gone through the 
 whole Art of the Malt - Stiller as it is pra<^ifed 
 by the more intelligent Artifts, we proceed to 
 offer a Confideration or two for its farther Im- 
 provement. 
 
 15. The Inconveniencies of this Art regard 
 cither the Subjedt, or the Work. The Subjedl, 
 we fee, is Malt ; which being of a large Bulk, 
 in Refpedt of its faccharine Part, and requiring a 
 great Proportion of W ater to extradf this Part, 
 hence many large Veffels, fuch as Mafh-Tuns, 
 
 Coolers, Fermcnting-Backs, Coarfe-Stills, and 
 Fine-Stills, become neceffary therein ; whereby 
 the Labour alfo is increafed, and the Price of 
 the Commodity enhanced. This Art, therefore, 
 being far removed from Simplicity, is confe- 
 quently far removed from Perfection. 
 
 16. The Remedy here fhould feem to de- Remedied, 
 pend upon the Introduction of a new Art, fub- 
 fervient to the Art of the Malt -Stiller^ and con- 
 fining itfelf to the Boiling down of Malt- Wort 
 
 to a Rob ^'1, fo as to fupply the Malt -Stiller 
 with his Subjedt, in the fame Manner that the 
 Fine-Stiller is now fupplied by the Sugar- Baker 
 
 «) See §. 9. 
 
 b) See lea. X. Exp. III. 
 
 R4 
 
 with 
 
24-8 
 
 Lecture the Twelfth. 
 
 with Treacle : For thus the complex Bufmefs 
 of the Malt- Stiller might be commodioufly re- 
 duced to a great Degree of Simplicity. 
 
 17. By the fame means the Spirit of the 
 Malt ‘Stiller would aifo become much finer than 
 at prefent ; becaufc the Subjed would comc^ 
 tolerably refined to his Hands, or purged of its 
 grofs, mealy, and hufky Matter, which yields 
 a difagreeable Oil in Diftillation ; and is alfo 
 apt to burn in the Still, and fpoil the Spirit. 
 We therefore recommend it to thofe who are 
 fkilled in this Branch of Diftillation, to try 
 whether a Spirit fuperior to that of Treacle may 
 not be procured from the Roh of Malt^ pru- 
 dently prepared and fermented 
 Tine-pui- 18. There needs no particular Experiment to 
 ftiew the bufinefs of the Fine- Stiller \ that being 
 no more than Working, in the Manner above 
 explained, from a Wafti made by fermenting 
 Treacle with Yeaft; though it is ufual to add a 
 confiderable Proportion of Malt, and fometimes 
 a little powdered Jalaps in the fermenting Back. 
 The Malt accelerates the Fermentation, and 
 makes the Spirit come out the cheaper ; and the 
 falap prevents the Rife of any crufty Head on 
 the Surface of the fermenting Liquor, and fo 
 leaves a greater Opportunity for the free Accefs 
 of the Air *, which alfo fhortens the Work, by 
 turning the foamy into the more hifling Kind 
 of Fermentation. 
 
 Exp X R j- 
 
of Diflillation. 
 
 249 
 
 Experiment III. 
 
 ^he Art of the Rectifier ; or the Method whereby 
 the Proof -Goods of the Mall- Stiller are made into 
 a cleaner Spirit^ for the finer Ufes of the Coin- 
 pounder and Apothecary. 
 
 19. To two Gallons of the common Proof- 
 
 Spirit of the Malt-Stiller, procured after the thn c/Spi- 
 Manner of our fecond Experiment, we added W/j. 
 three Ounces of the Black Flux, or a Mixture 
 of Tartar and Nitre calcined to Blacknefs * ; 
 and drew over all that would run in an uninter- 
 rupted Stream from the Nofe of the Worm, by 
 Means of the Balneum MarU. The Spirit which 
 thus came over we made up Proof with fair 
 Water. And the Spirit thus prepared is the com- 
 mon faleable Proof Goods of the redifying Diftil- 
 ler, when he works to a Truth. 
 
 20. This is the Spirit we commonly meet 
 with in Trade under the Name and Notion ofrzV. 
 Malt-Spirit.^ which is thus fitted for making the 
 common Cordial or compound Waters; being 
 cleared confiderably of its foetid Oil and nau- 
 feous Phlegm, by Redification. If it be defired 
 Hill cleaner one of the beft Methods is, to dilute 
 the ftrongeft Part that comes over firft, with a 
 large Proportion of fair Water, draw off the 
 Spirit gently again by the Balneum Marine., and 
 then make it up proof with fine foft Water. 
 
 21. But this Method will not yet give us the hicon‘ve.. 
 Spirit without fome naufeous and difagreeable 
 Flavour ; nor do the Redlifiers appear acquaint- 
 ed with any good Method for that Purpofe. 
 
 » See Lea. II. Exp. II. 
 
 They 
 
250 
 
 Lecture the Twelfth. 
 
 They have been groping after it, but generally 
 in the dark, for want of a proper Knowledge 
 of the Fads and Experiments necelTary in the 
 Enquiry. Thus, for inftance, they feem little 
 apprehenfive that it is the Oil of the Malt, 
 rcrfiding in the Spirit, which occafions ail their 
 trouble ; or that it is the eflential Oil of the 
 Subjed which gives to Malt-Spirits, Brandies, 
 Rums, and Arracks their particular Flavours, 
 For if the eflential Oil could be totally feparated 
 from Malt-Spirit, that Spirit might be rendered 
 flavourlefs and taftelefs ; and then any other 
 Flavour might, by Means of other eflential Oils, 
 be introduced into it *, fo that it might be 
 made to refemble either French Brandy, Rum, 
 or Arrack. And in the effeding of this, with 
 Simplicity and Cheapnefs, the Perfedion of the 
 Art of Redifying feems to confift, 
 
 'Remedied, For this purpofe we would recommend 
 
 the Way of Working from a Spirit largely dilu- 
 ted with Water, into Water again •, for thus the 
 elTential Oil would be doubly feparated at one 
 Operation. But we have no great Hopes that 
 any Diredion of this Kind can prove ferviceable 
 to them, while they remain unacquainted with 
 chemical Operations, and the bed Contrivances 
 for Diftilling in the large Way with Elegance 
 and Simplicity. 
 
 23. The Chernids, however, have helped 
 them to a tolerable Expedient for covering the 
 Imperfedions of the Spirit which they cannot 
 cleanfc*, viz, by the Addition of what is called 
 Spiritus Nitri dulcis ; a fmall Proportion whereof 
 will give an agreeable Vinofity to a Hogdiead 
 of Spirit. Bnt this Expedient is attended with 
 an Inconvenience ; for the Flavour is very apt 
 to fly od', or be lod, when the Spirit is kept in 
 a Calk : But the Succefs proves different, when 
 
251 
 
 Of Dijiillation. 
 
 the Spirit is kept and well (lopped down in a 
 Glafs. 
 
 24. The Art of the ReElifier might be entirely i^tpronje- 
 fet afide as ufelefs, if the original Malt - Stiller inents. 
 could make his Spirit perfed at a fecond Opera- 
 tion, as we judge he might. But here again the 
 Malt Stillers can fcarce be brought to forfake the 
 beaten Track. If they are difpofed to improve 
 their Art, we would recommend to them, 
 the Brewing in Perfedion ; and fecondly^ the 
 Keeping of their Wafh, after the Manner of 
 dale Beer, till it has entirely loft its Malt Fla- 
 vour, and acquired a pungent, acid, Vinofity ; 
 and then, thirdly^ leaving out the Lees, to diftil 
 with a well-regulated Fire. Thofe who have not 
 tried would fcarce conceive what an agreeable 
 Spirit may be thus procured from Malt, at the 
 very firft Diftillation. The gainful Part of the 
 Secret depends upon an artificial Method of making 
 Malt Liquors expeditiotifiy ftale^ bright^ and favour- 
 lefsy but in other refpebis vinous 
 
 Experiment IV. 
 
 The Method of examining Proof in Spirits ; and de- 
 tecting the Invalidity of the common IVays of judg- 
 ing of the Purity^ Genuinenefs^ and Goodnefs of 
 Brandies^ Rums^ and Arracks. 
 
 Z5. We took a long Phial, half filled with 
 the common Proof-Spirit of. the Malt- Stiller^ 
 and giving it a fmart Stroak with its Bottom 
 againft the Palni of the Hand, there appeared ‘ 
 on the Surface of the Liquor a Chaplet, or 
 Crown of Bubbles, which went off, or difap- 
 peared, in a certain ftrong Manner ; that is, it firft 
 
 *) See j^ppendix to Led, XI. See alfo te£l, VII. 
 
 remained 
 
252 
 
 Erroneous. 
 
 detection. 
 
 Sophijlica- 
 
 tion. 
 
 Lecture the Twelfth. 
 
 remained a while, and then went off by De- 
 grees, without breaking into fmaller Bubbles, 
 or rifing into larger. And when the Bubbles go 
 off in this Manner, the Spirit is faid to be proof 
 or merchantable 
 
 26. And by this Kind of Proof all Diftillers, 
 Brandy-Merchants, Brokers, and the Officers of 
 the Cuftoms and Excife, judge of the Strength 
 and Quality of Brandies and Spirits, in all the 
 Brandy-Countries and Sea-Port Towns of Eu- 
 rope ; wheace it is alfp conveyed to other Parts of 
 the World. It may therefore appear ftrange to 
 oppofe the general Opinion and Pradice, in a 
 particular where the Intereft of fo many trading 
 People, watchful againft all Impofition, is con- 
 cerned : And yet we undertake to ffiew, that 
 this Kind of Proof is a mere Fallacy and De- 
 ception •, for if but a little vinous or faccharinc 
 Matter, as 'I'reacle, Syrup, Muft, the Rob of 
 Fruits, Cfr. be added to a Quantity of highly 
 rediified Spirit of Wine, this flight Addition will 
 give a Brandy- Proof to that Spirit; which, 
 therefore, by this Trial, may be made to pafs 
 for Brandy ; that is, for a Compofition of half 
 Water and half Alcohol, whereas in Reality it 
 is almofl: totally Alcohol. 
 
 27. The Fraud is eafily detected ; not in the 
 common Way pra6lifed upon the K^Sy but by 
 burning a little of the Spirit in a Spoon ; for 
 thus it will leave ^he faccharine Matter behind 
 in a dry Form. 
 
 28. Whether there be any Method com- 
 monly known in EuropCy of making a fpirituous 
 Liquor that contains much lefs than a half 
 of Alcohol, to pafs current for Proof- Spirit, 
 is not fo certain : But doubtlefs this might be 
 
 * See Lea. VII. Exp, IV. § 36, 37. 
 
 eafily 
 
of Difillation. 253 
 
 might be eafily efFe^led ; for we fee that Arrack 
 is Proof, or affords a ftrong Crown of Bubbles, 
 upon lhaking, as well as Brandy ; yet Arrack 
 contains not ufually above half the Quantity of 
 Alcohol that Brandy does \ and if but a Drop 
 or two of its own or any other effential Oil be 
 added to a Pint of Proof-Brandy, this is fuffi* 
 cient to deftroy its Proof, and make it appear 
 much weaker than it is. 
 
 30. To prevent being impofed upon In xK\%Difcavery, 
 Way, we might have Recourfe to the EJfay- 
 Inftrument^ or Hydroftatical Balance. A Gallon of 
 Alcohol is computed to weigh feven Pounds and 
 
 a half, and a Gallon of Water, eight Pounds ; 
 whence the compound Gravity of an equal ' 
 Mixture of the two may be affigned. But it is 
 a more fure and ready Method, to burn a little 
 meafured Quantity of the Brandy to be tried, 
 in a cylindrical metalline Veffel, plunged in cold 
 Water to an equal Height with the Brandy, 
 and when it ceafes to burn, exa6Hy meafuring 
 the Remainder, which is the Water : Where if 
 the Spirit has loft one half of its Mealure by 
 Burning, the Brandy may be allowed Proof; if 
 more or lefs, it muft be judged of accordingly 
 
 31. But befides the falfe Method of judging of Efay U. 
 the Strength of Brandies by what is called Proof, 
 
 there is another no lefs fallacious one of judg** 
 ing of their Genuinenefs ; tho’ kept a great Secret 
 in few Hands, as a Thing fome Dealers imagine 
 a certain Criterion for determining whether 
 foreign Brandies are mixed with Corn Spirits. 
 
 Thefe Dealers are provided with a certain yel itsVfe. 
 low Liquor^ a few Drops whereof being poured 
 
 See a Paper by M. Geoffrey^ to this Purpofe, in the 
 Tranch Memoirs. 
 
 into 
 
254 - 
 
 Lecture THE Twelfth. 
 
 into a Glafs of right French Brandy, gives it a ?' 
 
 beautiful blue Colour ; by the Strength and ^ 
 
 Brightnefs of which Colour they judge of the ' 
 
 Genuinenefs, or unmixed State of the Commo- 
 dity, and buy upon this Kind of Proof : Whence 
 they may come to be much deceived ; for if an 
 ordinary Malt Spirit was to be coloured with 
 Oak, it would fuftain the prefent Method of 
 Proof, and might therefore be purchafed by 
 thefe Dealers for French Brandy. 
 llo-w 32 . This Proo-f’Tindlure, or EJfay Liquor^ 
 
 made. may be expeditioufly prepared, by dilTolving a 
 little green Vitriol (firft calcined to Rednefs) in 
 a weak Spirit of Sea-Salt ; v/hich thus becomes 
 a yellow Liquor^ a Tingle Drop or two whereof 
 being added to a Glafs of any inflammable Spi- 
 rit coloured yellow or brown with Oak, will 
 inftantly turn it of a beautiful bright Blue : 
 Whence it is evident that this Kind of Trial is 
 no more than a Fallacy, and only fhews when 
 Brandies are tinged with Oak, as they conftant- 
 ly are by lying long in the Cafk." And that it 
 is the Oak which thus caufes French Brandies to 
 turn blue with the EJfay Liquor ^ appears again 
 from hence ; That if the belt and oldelt French 
 Brandy be re diftilled, and thus made colourlefs, 
 it will not turn blue with the EJfay Liquor ; be- 
 caufe all the Tindture of the Oak, or tinging 
 Matter of the Cafk, is left behind in the Still. 
 
 Its Fallacy 33* One of the bed Methods to prevent being 
 deteatd. impofed upon by the Mixing of Malt-Spirit 
 with a finer, is to acquire a Habit of judging 
 by the Tafle and Smell ; for Malt-Spirit is ufu- 
 ally To ill redfified, by the Addition of fixed 
 alkaline Salts, or certain flavouring Ingredients, 
 that it may eafily be perceived by the Nofe 
 or Palate ; efpecially if the Brandy propofed for 
 Examination be largely diluted with Water, to 
 
 prevent 
 
of Difillation. 255 
 
 prevent its over-heating the Mouth ; or elfe be 
 burnt in a Spoon, fo as to leave the Phlegm to 
 be tailed and fmelt by itfelf : For this Phlegm, 
 if the Brandy were debafed by a Corn Spirit, 
 will tafte and fmell exceedingly naufeous, very 
 different from the Phlegm of pure French Brandy. 
 
 Experiment V. 
 
 ^he heft Method of making Cordial or Compound 
 Waters, 
 
 54. We infufed a Pound of frefh Citron-Peel Ciiron 
 in two Gallons of good Melaffes Spirit, and tVaterfre- 
 committing the whole to the Still, drew off the^'*''^'^- 
 Spirit gently, with Care to avoid the Faints ; 
 then making up^ as they call it, with foft Wa- 
 ter, fo as to leave the Liquor Proof, we added 
 half a Pound of fine Sugar, and thus procured 
 a genuine Citron Water, 
 
 35. This Experiment is general, and ixpe- 
 
 the ufual Methods of making all the Compound rimentex- 
 or Cordial Waters, by thofe Diflillers who are 
 
 called Compounders, and alfo by Apothecaries *, 
 tho’ Apothecaries feldom make diflilled Waters 
 fo good as the Compounders. 
 
 36. The Perfe6lion of this Branch of Diftilla- Compound 
 tion depends upon the Obfervance of a few Diftuia- 
 Rules, which might be eafily complied with : 
 
 And thefe Rules we fhall here lay down, as jiidg- 
 ing them of Confequence to the Improvement 
 not only of the Art of the Compounder, but al- 
 fo of a Branch of Pharmacy and Medicine. 
 
 37. The firfl Rule is, "To uje a well-cleanfed Hules, 
 Spirit^ that is freed from its own ejfential Oil. For 
 
 as the Defign of compound Diflillation is to 
 impregnate the Spirit employed with the effential 
 
 Oil 
 
256 Lecture theTwelfth. 
 
 Oil of the Ingredients, it ought firft to have dc- 
 pohted its own. 
 
 38. The fecond Rule is, ^0 fuit the Time of 
 previous DigelUon to the Tenacity of the Ingredient Sy 
 or the Fonder oft ty of their Oil, Thus Rhodium- 
 Wood and Cinnamon require to be longer di- 
 gelled before they are diftilled than Calamus 
 Aromalicus^ or Lemon-Peel. Sometimes alfo 
 Cohobation (that is, the pouring of the Spirit once 
 drawn off, back upon the fame Ingredients) 
 proves neceffary ; as particularly in making the 
 ilrong Cinnamon Water, where the effential 
 Oil is extremely ponderous, and hardly rifes 
 along with the Spirit, without one Cohobation 
 more. 
 
 39. The third Rule is. To fuit the Fire or 
 Strength of the Diftillation to the Ponderofty of the 
 Oil intended to be raifed with the Spirit. Thus 
 ftrong Cinnamon Water Ihould be diftilled off 
 brilker than the Spirit of Mint or Baulm. 
 
 40. The fourth Rule is. That a due Propor^ 
 fion of only the finer effential Oil of the Ingredients he 
 thoroughly united or incorporated with the Spirit^ fo 
 as to keep out the gr offer and lefs fragrant Oil. And 
 this may be chiefly effeefted by leaving out the 
 Faints,, and making up to ftrong Proof with fine 
 foft Water in their Stead. And upon the Ob- 
 fervance of thefe four eafy Rules the Perfedlion 
 of the Art of compound Diftillation feems to 
 depend. 
 
 41. The Addition of fine Sugar to Cordial 
 Waters is a Thing of lefs Moment, and may be 
 ufed or omitted occafionally. And if thefe Di- 
 redlions be obferved, there will be no need of 
 fining down Cordial Waters with Allum, WTites 
 of Eggs, Jfing-Glafs, or the like ; for they v>ill 
 be prefently bright, fweet, and pleafantly tafted, 
 without any farther Trouble. 
 
 42. And 
 
Of Diftillation. 257 
 
 ^42. And thus we hope to have fhewn the Way 
 of perfeding the Art of compound DiftiUation, 
 
 : even by the common Alembic, or hot Still, with- 
 i out the Ufe of the Balneum Mari^ ; for which ^ 
 
 ! there is here no Occafion, if the Artifl; be but 
 expert in working by the Alembic. 
 
 j Axioms and Canons. 
 
 I I. We learn from our prefent Enquiry, that 
 inflammable Spirits are the Creatures of vinous 
 Fermentation ; or that they are adually produc- 
 ed, tho* not feparated, in that Operation a). 
 
 2. That the Adion of Fermentation produces 
 fuch a Change in the Wafh, as to render it fe- 
 
 - parable by the Fire into feveral Portions of Mat- 
 ter, befides the inflammable Spirit, fpecifically 
 I different from what the Liquor would have af- 
 forded by the fame Treatment before Fermen- 
 tation h). 
 
 3. That at different Times of Diftillation there 
 come over Liquors of different t^roperties ; and 
 firft of all, an extremely acrid, aromatic, and 
 biting one ; which goes off by Degrees, and ends 
 in Acidity c), 
 
 4. That the Art of Malt-Stilling may be con- 
 fiderably improved •, (i.) by reducing the brew- 
 ing and fermenting Parts to one Operation ; 
 
 (2.) by diftilling flow, and (3.) by keeping back 
 the grofs Oil of the Subjed. 
 
 5. That this Art^ may be farther improved, 
 by fermenting a clear, well-brewed Wort, and 
 keeping it to be ftale, or till it has loft all Fia- 
 
 a) See Exp. I. 
 
 />) See Lect. VIT. Exp IV. See alfo /Appendix to tccl. XI. 
 
 r) See Exp. I. and Appendix to Ledt. XI. 
 
 s 
 
 vour 
 
258 Lecture the Twelfth. 
 
 vour of the Malt •, as it will naturally do by long 
 lying, or in a very fliort Time by the Help of a 
 certain artificial Treatment a). 
 
 ' 6. That the Perfedlion of the Art of Mah- Stil- 
 ling requires the AlTillance of a new Art, to pro- 
 duce a Kind of Treacle from Malt, or the Re- 
 dudlion of the Art ot zhc Malt- Stiller to the fame 
 Simplicity as that of the Fine Stiller a), 
 
 7. That the effential Oil of the vegetable Sub- 
 jedl: is the Thing which gives to ail Spirits their 
 particular Odours and Flavours b). 
 
 8. That the fineft, moft fubtil and efficacious 
 Fart of this effential Oil always rifes firff: in Di- 
 ffillation b). 
 
 9. That the Purity and Perfedhion of Spirits, 
 confidered merely as Spirits, greatly depend upon 
 their being cleanfed firff: of the effTential Oil, 
 efpecially its grolTer Part, and next of the 
 Phlegm c). 
 
 20. That Brandies are a Mixture of one half 
 Vv^ater, and the other half Alcohol; that the 
 Meafure of the Strength of Brandies is the Qiian- 
 tity of Alcohol they contain ; and therefore that 
 their Water may be commodioufly left behind 
 upon Exportation or Carriage d). 
 
 1 1. That as Brandies hold fome fmall Propor- 
 tion of effential Oil, they are in Stridnefs di- 
 lute Quinteffences c) \ whence their Properties 
 and Effeds may be eafily explained, in a chemi- 
 cal Manner. 
 
 a) See Exp. I. and III. 
 
 h\ See Exp. I. HI. V. 
 
 0 See Exp. I, II, III. V. 
 
 d) See Exp‘ 1, II, HI, IV. 
 
 12. That 
 
Of Difillation. 
 
 11. That the Perfedlion of Redifying Spi- 
 ! rits depends upon finding out a fimple Method 
 I of fepararing all the Uii and Water from a 
 > Spirit a). 
 
 13. That the great Affinity betwixt the effen- 
 tial Oil and Spirit is the phyfical Caufe of the 
 Difficulty found in the Redification of Bran- 
 I dies b). ' 
 
 I 14. That the Perfedlion of the Art of MaU- 
 I Stillings whereby a pure Spirit might be procured 
 ' at the firft Operation, would fuperfede the Art 
 of Reclifying a). 
 
 15. That the Bubble Brandy-Proof may be 
 artificially given to high redfified Spirit of Wine, 
 and eafiiy deftroyed in Proof-Spirit, without 
 
 I weakening the Spirit c). 
 
 16. That the common Methods of trying and 
 examining Brandies by the Bubble-Proof, and by 
 their turning blue with a vitriolic Solution, are 
 abfolutely fallacious, and not to be trufted for 
 the Purpofes intended d). 
 
 17. T\\2X phyfical Proof \n Brandies is the Pro- 
 perty they have, upon fhaking, to generate a 
 Crown of moderately large Bubbles on their 
 Surface, by Means of a certain Tenacity, arifing 
 from a dated Proportion of effential Oil diiTol- 
 ved in among them •, which Tenacity may alfo 
 be given by other Bodies d). 
 
 18. That a fure Method of determining the 
 Strength of Brandies is by Deflagration, or 
 burning away their Alcohol ; then examining the 
 remaining Phlegm by Weight or Meafure, and 
 
 a) See Exp lU. 
 
 0 Exp. I, II, III V. 
 
 0 Exp. Ill, iV. 
 
 J) Exp.lY. 
 
 S 2 
 
 comparing 
 
26o L'ecture the Twelfth. 
 
 comparing it with the Weight or Meafure of 
 the Alcohol a), 
 
 19. That erroneous Notions, or inaccurate 
 and falfe Methods of Trial, may prevail, and 
 become almoft univerfal in Trade ; fo that even 
 the prudent Merchant (hall buy and fell upon 
 weak Trials, whilfl: the Dete6lion, Rectification, 
 or Adjuftment thereof, belongs to fomc other 
 Branch of Knowledge a), 
 
 20. That the Way of perfecting the Art of 
 compound Diftillation is, (i) To procure a 
 well-cleanfed Spirit; (2) To ufe proper Dige- 
 ftion; (3) To diftil briflc, or flow, as the Sub- 
 ject requires ; and (4} To keep back the Faints, 
 and the grofs Part of the eflential Oil of the In- 
 gredients b), 
 
 d) Exp. IV; 
 
 F) Exp.Y. 
 
 LEG- 
 
I 
 
 [ 261 ] 
 
 LECTURE XIII. 
 
 CONTAINING 
 
 T!he Ways of procuring Vegetable Oils and 
 Salts ; ^ith their Ufes in feveral Arts and 
 Trades. 
 
 I. 
 
 I. T 7 C 7 E proceed to illuftrate and im- The Sub- 
 V V pi*ove the common Methods of pro-i^^* 
 curing and employing vegetable Oils and Salts ; 
 on which the Exercife of various Arts and Trades 
 depends. 
 
 2. The Parts of Vegetables that chiefly abound The oily 
 with Oil are, the Seed, the Leaves, the Fruit, e/' 
 and the Bark. Thus the Seeds of Milliard, and 
 
 of the Sun-Flower, Almonds, Nuts, Beech- 
 Mali, afford a copious Oil by Expreffion ; 
 and the Leaves of Rofemary, Mint, Rue, 
 Wormwood, Thyme, Sage, fsfr. the Berries of 
 Juniper, Olives, Indian Cloves, Nutmeg, Mace, 
 
 Li’r. the Bark of Cinnimon, Saffafras, bcc. yield 
 a confiderable Proportion of effential Oil by 
 Diflillation 
 
 3. And much in the fame Manner is Oil or 
 Fat contained in the Parts of Animals ; being 
 either interfperfed among the mufcular Flefh, 
 colledled into particular Bags or Cells, or lodged 
 in the Cavities of the Bones, 
 
 See below, Exp. II. 
 
 s 3 
 
 4. Our 
 
262 
 
 ^he De/ign 
 of the Ex- 
 periments. 
 
 Exprejfed 
 Otl of Al- 
 monds. 
 
 ^he Expe- 
 riment ex- 
 tended. 
 
 Lecture the Thirteenth. 
 
 4. Our Experiment will fhew the Me- 
 thod of procuring Oils by ExprefTion, from 
 Nuts, Seeds, Maft, Olives, i^c. T he Expe- 
 riment will exhibit the Method of procuring thofe 
 called the Elfential Oils of Vegetables. The 
 third Experiment will fhew the Method of rec- 
 tifying thofe called the Empyreurnatic Oils. 
 Our fourth Experiment will fliew the Method 
 of refining Sugar. The fifth Experiment will 
 fhew the Way of refining Tartar : Our fxth 
 the Manner of refining Nitre., or Salt-Petre ; 
 and our feventh will fhew the Method of mak- 
 ing Pot-Afh. 
 
 Experiment I. 
 
 The Method of procuring Oil hy Exprejfion^ from 
 Nuts-i Seeds Maft., &c. 
 
 / 
 
 5. We took two Pounds of SwTet Almonds, 
 blanched, and beat them fmall ina Stone Mortar ; 
 then wrapping the Mafs up in a Piece of ftrong 
 and thick Canvas, we committed it to a ftrong 
 Screw-Prefs •, where being fqueezed betwixt two 
 cold Iron Cheeks, it gradually parted -with a 
 confiderable Quantity of Oil. 
 
 6. This Experiment holds of all thofe vege- 
 
 table Matters that contain a copious Oil, in a 
 loofe Manner, or in certain Cavities or Recep- 
 tacles 3 the Sides whereof being burft by 
 fqueezing, makes them let go the Oil they con- 
 tain. And thus the Zeft, or Oil of Lemon- 
 Peel, Orange Peel, Citron-Peel, may be 
 
 readily obtained by Preflure, without the Ule 
 of Fire ; for the Rinds of thofe Fruits being pref- 
 fed green, the oily Parts will feparate from the 
 
 aqueous. 
 
Of oils and Salts. 
 
 aqueous, and may be rendered pure by wafliing 
 them in fair Water *. 
 
 7. How far this Method of obtaining Oils may 
 be applied to Advantage, feems not hitherto 
 confidered. It has been commonly applied to 
 Olives, Almonds, LintAeed, Rape-feed, Beech- 
 Mad, Ben-Nuts, Wallnuts, Bay-Berries, Mace, 
 Nutmeg, ^c. but not that we know of to Ju- 
 niper-Berries, Cachou-Nuts, IndianClowts^ Pine- 
 Apples, or Fir-Nuts, and m^any other Subjects 
 that might be enumierated, both of foreign and 
 domeftic Growth. It has however been of late 
 applied to Muftard-feed, with good Succefs ; fo 
 as to extradl a curious yellow, or golden-colour- 
 ed Oil from that Seed, and at the fame Time 
 leave a Cake behind fit for making the com- 
 mon Table Muftard. 
 
 8. Certain dry Matters may, as well as moifl 
 ones, be made to afford Oils by Expreflion j for 
 when they are not fo moift as Almonds, or fit 
 to be reduced to a Pulp in a Stone Mortar, they 
 may be ground into a Meal, which, being fu- 
 fpended to receive the Vapour of boiling Wa- 
 ter, will thus be moiflened fo as to afford an Oil, 
 in the fame Manner as Almonds ; efpecially if 
 the Iron Cheeks employed be firfl heated, by 
 lying in boiling Water. And thus an Oil may 
 be procured from Lint-feed, Hemp-feed, Let- 
 tuce-feed, White Poppy- feed, Ct’c. 
 
 9. The Oils obtained by this Treatment, 
 fliould be fuffered to depurate themfelves by - 
 ftanding in a moderately cool Place, to fepa- 
 rate from* their Water, and depofite their F^ces ; 
 from both which they ought to be carefully 
 freed. And if in this Manner they are not 
 
 ^ See below, § 9. 
 
 S 4 
 
 rendered, 
 
264 Lecture the Thirteenth. 
 
 rendered fufficiently pure, they may be well 
 wafhed and beat with frefli Water, and then 
 thoroughly feparated/rom it again, by the Sepa- 
 rating-Glafs ; by which Means they will be ren- 
 dered bright and clean. 
 
 10 Particular Care muft be taken to keep 
 fuch of thefe Oils cool as are defigned for eat- 
 ing, or for any internal Ufe ; becaufe they are 
 apt in a few Days Time to turn rancid and cor- 
 rofive with the Summer’s Heat, fo as to prove 
 very unwholdome. Hence the Phyfician and 
 Apothecary fhould be cautious that the Oils gi- 
 ven in Pleurifies, and other Diftempers, be frdli 
 drawn from found Subjeds, no way tainted, or 
 already turned rancid, as Almonds, Piftachios, 
 and other Nuts, are apt to be : And again, that 
 thefe Oils have felt no confiderable Heat, either 
 in the Drawing, or by landing long in a 
 warm i'lace. And the fame Caution fhould 
 likewife extend to animal Oils and Fats, intend- 
 ed either for internal or external Ufe ; fince 
 thefe aifo become rancid, or change to a yel- 
 low, red, or grey Colour in hot Weather, and 
 thus become exceedingly naufeous andcorrofive ; 
 as we fee in Butter, Bacon, and other fat Bo- 
 dies, which then prove fit only for the Tallow- 
 Chandler, or other ignoble Ufes. 
 
 Applied to II. Our prefent Experiment is likewife ap- 
 
 othei Sub plicable to the procuring of Oils or Fats from 
 certain animal Subjeds ; for the Membranes, 
 the fldnny, and firingy Parts of animal Bodies, 
 which contain much Fat, being chopped fmall, 
 and let in a Pan over the Fire, become nt for the 
 Canvas- Bag, and by Preffure afford a large 
 Quantity thereof ; as we fee in the Art of 
 Chandlery, which thus extrads the oily Matter, 
 
 leaving 
 
Of Oils and Salts. 265 
 
 leaving behind a hard Cake, or what they com- 
 monly call Graves. 
 
 12. Thefe Graves^ and all the Refiduums of 
 the prefent Procefs, after being fqueezed ever 
 fo hard with the Frefs, will flill afford a copious 
 OiJ by boiling in Water; fo that it might per- 
 haps be more profitable for the "Tallow Chandler • 
 to boil his Graves for Oil, as Bones are ufually 
 boiled for it, than to difpofe of them in the or- 
 dinary Manner. And it is furprizing to obferve, 
 what a large Proportion of Oil thefe dry, and 
 to appearance almofl exhaufted Bodies, will 
 yield, by repeated boiling in Water, but parti- 
 cularly by being committed to the Digeftor 
 
 13. So likewife if the Almonds remaining in Farther 
 the Canvas, after the Exprefiion of their Oil, be 
 ground in a Mortar with warm Water, the Wa- 
 ter will thus extradc their remaining Oil, and 
 
 turn therewith into a milky Liquor, or Emulfion. 
 
 And if this Operation had been periormed upon 
 the Almonds at firfl, before we committed them 
 to the Prefs, we might thus have got out all their 
 Oil, and left only a dry, chaffy, or light, huflcy, 
 and exhaufted Matter behind. Whence we have 
 a Method of difiblving Oils in Water, and there- 
 by of making a Kind of artificial Milk ; which, 
 by ftanding, will afford a Cream, and turn four, 
 like the Milk of Animals, but not grow rancid 
 with Heat, like Oil. Whence fucff Emulfions 
 may, in fome Cafes, be medicinally ufed with 
 greater Safety and Succefs than expreffed Oils. 
 
 14. Any of thefe exprefied Oils will receive 0//Wc- 
 particular Colours and Odours at the Difcre- hurcd. 
 tion of the Artift. For Example : If a little 
 
 * See Ua.ll.Ext. VII. 
 
 Alkanet- 
 
266 Lecture the Thirteenth. 
 
 Alkanet-Root be barely infufed in Oil-Olive, it 
 gives a beautiful red Colour to that Oil, with- 
 out altering its Tafte. So again ; if a few Drops 
 of the eflential Oil of Cinnamon be added to a 
 Pint of Sallad Oil, fuch Sallad Oil may be ren- 
 dered thereby agreeable to thofe who admire 
 the Flavour of Cinnanjon. And thus may Oil, 
 Butter, ^c. be diverfified infinite Ways, by a 
 proper Ufe of tinging Ingredients, and fuicable 
 chemical Oils. 
 
 Ifenceu i§. The fame Contrivance has likewife its 
 ' Ufes in making Effences for the Service of the 
 Perfumer ; not only where elTential Oils are pro- 
 , curable, but alfo where thefe either cannot well 
 be obtained, or but in fmall Quantity. The ef- 
 fential Oil of Jaf nin FlovN^ers, Honey-Suckles, 
 Sweet Briar, Damafk Rofes, Lilies of the Val- 
 ley, are either extremely dear, or fcarcely 
 obtainable by Diftillation ; and in fome of them 
 the odorous Matter is fo fubtil as to be almoft 
 loft in the Operation. But if Jafmin Flowers, 
 Damafk Rofes, Lilies of the Valley, be 
 barely infufed in fine Oil of Nuts, or Oil of Ben, 
 drawn without Heat, and kept in a cool Place, 
 the fubtil odorous Matter of the Flowers will 
 thus pafs into the Oil, and richly impregnate it 
 with their native odoriferous Spirit *, which can 
 fcarce otherwife be procured, or feparated from 
 the Flowers, without Lofs, or Debafement. 
 And thefe Effences may be rendered perfedf by 
 ftraining off the Oil at firft put on, letting 
 it ftand again, without Fleat, upon frefh 
 Flowers, and repeating the Operation twice or 
 thrice. 
 
 M'hat they ^ we confider the Thing attentively, we 
 fiiall find that the Effences thus obtained are a 
 Kind of ejfential Oils^ not greatly differing from 
 thofe prepared by Diftillation from the Flowers, 
 
 Seeds, 
 
Of oils and Salts. 267 
 
 Seeds, or Barks of odoriferous Vegetables *, for ■ 
 all fuch ejfentid Oils are found to be little more 
 than the native odorous Spirits of the vege- 
 table Subjedf, wrapped up, lodged, or entan- 
 gled in an unduous or dired oily Subftance. 
 
 This oily Subftance indeed rifes, or becomes 
 volatile, by the Heat of boiling Water ; but 
 fo do not the Oils gained by ExprefTion ^ : 
 Whence the principal Difference betwixt thofe 
 natural^ and artificial efiential Oils., as we may 
 call them, feems to confift; in the different Te- 
 nacity, Volatility, or Fixednefs of their undu- 
 ous or dired oily Parts, the native Spirit ap- 
 pearing the fame in both •, tho’ indeed it is 
 more delicate and unimpaired in the artificial 
 Kind of effential Oils, as not having felt the 
 Force of Fire. And hence perhaps fome con- 
 fiderable Improvements might be made in the 
 Art of the Oilman, Perfumer, and Apothecary ; 
 not to mention other oeconomical Ufes, and the 
 Art of the Dairy. 
 
 Experiment II. 
 
 Phe Method of procuring the effential Oils of Vege- 
 tables by Diftillation with IVater. 
 
 ly. We took eight Pounds of Juniper Effential 
 ries, and bruifing them in a Stone Mortar, 
 diredly put them into a Still, together with four 
 Gallons of River- Water •, then working with 
 briflc Fire, we drew off a Gallon of Water, and 
 obtained along with it a confiderable Propor- 
 tion of a fragrant effential Oil, which we 
 
 See Exp, II. hereafter. 
 
 fepa- 
 
268 
 
 ^he Expe- 
 rt me tit ex 
 tetided. 
 
 Ufes. 
 
 EJJential 
 Oils daf- 
 fed. 
 
 Lecture the Thirteenth. 
 
 feparated from the Water by a Separating- 
 Gials. 
 
 1 8. This Experiment is eafily rendered ge- 
 neral, or made applicable to the Diftilling of 
 the eiTential Oils from Flowers, Leaves, Barks, 
 Roots, Woods, Gums, and Balfams, with a 
 flight Alteration of Circumftances *, as by longer 
 Digeftion, brifleer Diflillation, according to 
 the Tenacity and Hardnefs^ of the Subjedl, the 
 Ponderofity of its Oil, a), 
 
 19. If the Liquor that remains in the Still, 
 after the prefent Operation, be ftrained, and 
 evaporated to the Confidence of Honey, it 
 makes the Roh of Juniper-Berries^ which may per- 
 haps defray the Charge of the Operation, it being 
 efleemed a valuable Medicine, and ufed as a 
 Strengthener of the Stomach and Inteftines, as 
 a Prefer vative from the Stone and Dropfy, and 
 as a Cure for the Diforders of the urinary Paf- 
 fages. 
 
 20. EiTential Oils may be divided into two 
 Claires, according to their different fpecific 
 Gravities *, fome floating upon Water, and 
 others readily finking to the Bottom thereof. 
 Thus the eflential Oils of Cloves, Cinnamon, 
 and Saffafras readily fink*, but the Oils of La- 
 vender, Marjoram, Mint, fwim in Water. 
 The lighteit of thefe eflential Oils is, perhaps 
 the Oil of Citron-Peel, which floats even on Spirit 
 of Wine *, and the heaviefl; feems to be the Oil of 
 Saffafras : But the fpecific Gravities of the in- 
 termediate eiTential Oils are not hitherto ad- 
 jufled and tabled, as for the Service of Chemifl:ry 
 they ought to be b). 
 
 a) See Led. XII. Exp. V. 
 h] Seebebvv, 29. 
 
 * 21. For 
 
Of Oils and Salts. 269 
 
 21. For obtaining the full Quantity of 
 
 more ponderous Oils from Cinnamon, Cloves, t^^jnedto 
 Saffafras, it is proper (i) to reduce the 
 
 Subjeds to fine Powder *, (2) to digeft this 
 
 Powder for fome Days in a warm Place, with 
 thrice its Quantity of foft River Water, made 
 very faline by the Addition of Sea-Salt, or fharp 
 with Oil of Vitriol; (3) to ufe the drained 
 Decodion, or Liquor left behind in the Still, 
 inftead of common Water, for a frelh Dige- 
 ftion ; (4) to ufe for the fame Purpofe the Wa- 
 ter of the fecond Running, after being cleared 
 of its Oil; (5) not to diftil too large a Quan- 
 tity of thefe Subjeds at once ; (6) to leave a 
 
 confiderable Part of the Still, or about one 
 
 fourth, empty ; (7) to ufe a briflc Fire, or a 
 ftrong boiling Hear, at the firft, but to fiacken 
 it a little ^terwards ; (8) to have a low Still- 
 Head, with a proper internal Ledge and Cur- 
 rent leading to the Nofe of the Worm ; and 
 (9) to cohobate the Water, or pour back the 
 Liquor of the fecond Running upon the Matter 
 in the Still, repeating this once or twice. 
 
 22. Thefe Cautions are all necelTary, in or- Reafons of 
 der to diftil the ponderous eftential Oils to Pro- the Cau- 
 fit and Perfedion. The phyfical Reafons where- 
 
 on they depend may deferve to be confidered. 
 
 (i) The Redudion of the Subjed to Powder, 
 expofes all its Parts the better to the Adion of 
 the Water and Salt ; whereby the Oil is the 
 more mollified, attenuated, and rendered fitter 
 to rife along with the aqueous Vapour in Diftil- 
 lation. (2) The Digeftion is requifite for the 
 fame Reafon ; as being no more than allowing 
 Time for this Adion to be performed, in a mo- 
 derate Warmth. The Water fhould rather be 
 the foft Water of Rivers, than that of Rain, 
 which is more corruptive or fermentative ; or 
 
 than 
 
270 Lect URE THE Thirteenth. 
 
 than that of Springs, which is often hard, fo as 
 not to mollify the Oil, but rather defend it from 
 the Adlion of the Salt, or Acid ; which are 
 added not only to prevent all Tendency to Fer- 
 mentation or Corruption, that would abfolutely 
 change or deftroy the Oil, but more particu- 
 larly, as having a known Property of attenua- 
 ting, liquifying, diffolving, and purifying grofs, 
 vifcous, and tenacious Oils. Befides which, 
 it likewife increafes the fpecific Gravity of the 
 Water ; whereby the Subjed; is now buoyed up, 
 fo that it cannot readily touch the Bottom of 
 the Still, or come in the way of the Fire to 
 be fcorched. At the fame Time this Addition 
 aifo increafes the Heat of the Liquor, or makes 
 it exceed that of iPiCre boiling Water ; whence 
 the Afcent of the Oil is likewife promoted. 
 (3) The drained Decodion is propq^ly ufed in- 
 ftead of Water, as being already faturated with 
 oily Particles, fo that it cannot much rob the Sub- 
 ject. And (4.) the fame holds alfo of the Water 
 of the fecond Running, which neceflarily con- 
 tains fome oily Particles. (5) If too large a 
 Quantity of the Subjed: be diftilled at once, 
 the FIcat will neceffarily ad: unequally, or be 
 ffrong upon fome Parts, and weak upon others *, 
 whence, as the Oil is fo extremely ponderous, 
 a large Fart of it will be left behind in the Sub- 
 je6f. (6) If too much empty Space be left in 
 the Still, it will be difficult for the ponderous 
 Oil to afcend ; and if too intenfe a Heat be 
 ufed, it deftroys the grateful Odour of the 
 Oil, without raifing any confiderable Quantity ; 
 and if the Still be filled too full, the Matter 
 will be apt to boil over, and foul the Oil. 
 (7) The Fire is ordered to be brifk at firft, to 
 prevent the Oil, now in fome Meafure feparated 
 by the Heat, from going back into the Subjed: : 
 
 But 
 
271 
 
 of Oils and Salts. 
 
 i But after a Part is thus come over, if the Fire be 
 not a little flackened, the Oil is apt to fcorch, 
 
 : and come out at the Nofe of the Worm in the 
 
 i Form’ of a Smoke, that cannot be catched and 
 . condenfed 5 yet the whole Operation need not 
 be continued long, or above two Hours, becaufe 
 the valuable Part of the Oil foon comes over. 
 
 (8.) If the Head of the Still be not low, the pon- 
 derous Oil will have too far to rife ; and unlefs 
 the Oil be direded to the Worm by a proper 
 Ledge and Current, a confiderable Part will fall 
 back into the Still, and fo prolong the Opera- 
 tion, or lefTen the Yield. (9.) Laftly, two or 
 three Cohobations, or Returns of the Water upon 
 the Subjed: in the Still, mult needs bring over 
 all the Oil that will any way rife. And Water 
 already fomewhat impregnated with the Oil, is 
 manifeftly better for the Purpofe than fuch as 
 has never been ufed before. 
 
 23. The Diredions here laid down, for ob- 
 taining the ponderous effential Oils to Advan- 
 tage, are eafily transferred to the obtaining of 
 the lighter : So that we need not dwell particu- 
 larly upon them. 
 
 24. Many of thefe effential Oils being coftly Effential 
 things, it is common to adulterate or debafe 
 them feveral Ways, fo as to render them cheaper 
 both to the Seller and Buyer. Thefe feveral 
 Ways feem reducible to three general Kinds, each 
 whereof has its Method of Detedion ; for as in 
 Logic every Sophifm has its Redargution, fo in 
 Chemiftry every Fallacy may be difeovered. 
 
 25. Effential Oils are adulterated, fi.j with 
 expreffed Oils, f 2. J with Alcohol, and ('3.Jwith 
 cheaper effential Oils. 
 
 26. (i.) If any effential Oil be adulterated 7 “/^^ 
 with an expreffed Oil, this is eafily difeovered, difconter^ 
 by adding a little Alcohol to.a few Drops of the 
 
 fufpeded 
 
272 
 
 Lecture the Thirteenth. 
 
 fufpe( 5 led effentiaJ Oil, and diaking them toge- 
 ther: For the Alcohol will thus diiTolve all the 
 Oil that is truly eiiential, or gained by Diftilla- 
 tion, but leave the exprelfed Oil untouched j where- 
 by the Compound of the two will be feparated, 
 fo as that their Quantities may be judged of, or 
 the Proportion ot the Debafement found : And 
 then by adding Water to the Alcohol, which had 
 taken up the eflential Oil, the Water will unite 
 with the Alcohol, and leave the eflential Oil fe- 
 parabie in its own Form. 
 
 27. (2.) It an eflential Oil be adulterated 
 with Alcohol, as it may be in any Proportion 
 up to that of an equal (^lantity, without being 
 eafily difcoverable either by the Smell or Tafte : 
 the Way of Detection is, to let a few Drops of 
 the fufpeded Oil fall into a Glafs of fair Water; 
 tor if Alcohol be mixed with the Oil, the Water 
 v/ili immediately turn milky, which it would 
 not do if the Oil were pure. And by continu- 
 ing to fhake the Glafs, the whole Quantity of 
 Alcohol employed in the Adulteration will 
 unite with the Water, and leave the Oil un- 
 diflblved behind. 
 
 ( 3 ') The third Method above mentioned, 
 of adulterating the richer chemical Oils, is by 
 mixing them with the cheaper eflential Kinds ; 
 fuch In particular as the Oil of Pine- Wood, Oil 
 cf Turpentine, &c. And this is frequently 
 praflifed, by putting Fir-Wood, Turpentine, or 
 Oil of Turpentine, into the Still, along with 
 the Herbs, fuppofe Rofemary, Lavender, Ori- 
 ganum, (sfc. in the fame Manner as Diftillers 
 add common Malt Spirit in theDiftilling of Wine 
 Lees And by this Means the Yield or an Oil 
 may be confiderably increafed. But the Oils 
 thus adulterated wdll difcov^er themfelves in 
 Time, by the want of their natural Flavour, 
 
 which 
 
of Otis and Salts, 273 
 
 ^hich is overpowered by that of the Turpen- 
 tine, But the quicker Detedion is, to 
 
 drench a Piece of Paper, or a Linen Rag, in 
 the fufpeded Oil, and hold the Paper or Rag 
 before a gentle Fire; for thus th^ grateful Odour 
 of the Plant will foon fly off, and leave only the 
 Smell of the Turpentine, 
 
 29. But if this Way of adulterating efiential 
 Oils be pradflfed in Perfedlion, it feems fcarce 
 difcoverable, unlefs the ^ahle of the fpecific Gra~ 
 vities of effential Oils, above recommended 
 were ready at Hand. For it is known to fome 
 few that Balfam Capivi yields a large Propor- 
 tion of elTential Oil by Diftillation with Water, 
 even to the quantity of five or fix Ounces from 
 a Pound; and that this Oil is much fweeter 
 than any of thofe before faid to be ufed for 
 Adulteration : Whence it is eafy by diftilling 
 any of the aromatic Vegetables along with this 
 Balfam, or by mixing their Oils with the Oil 
 of Balfam Capivi,, to debafe them largely, with- 
 out being greatly fubjedl to Difeovery, except 
 by the more philofophical Chemifis, who under- 
 hand the ufes of the Hydroftatical Balance, But 
 it fhould be obferved whether, by long keep- 
 ing, the chemical Oils thus adulterated with the 
 Oil of Balfam Capivi^ will not difeharge the 
 Ink of the written Label, faftened to the con- 
 taining GJafs, as efiential Oils adulterated with 
 Oil ot Turpentine, or other terebinthinaccous 
 Oils, are found to do, on account of the acid 
 Vapour that continually exhales from fuch adul- 
 terated Oils. 
 
 30. The Methods already laid down for de- 
 tecting the Sophiftications commonly praClifed 
 in efjential Oils,, are general ; btfides which 
 
 ^ See §. 20. 
 
 T 
 
 fome 
 
2 74 Lecture the Thirteenth. 
 
 fome Oils require peculiar Methods. Thus the 
 efifential Oil of Camomile Flowers may be cer- 
 tainly known to be adulterated with Copper and 
 Oil of Turpentine, Cfc. if it retains its original blue 
 Colour above a Year. The efifential Oil of Rue^ 
 if genuine, remains fiuid in the Cold, and if a- 
 dulterated, congeals. And every Fad of this 
 Kind, of which there are many already known, 
 fhould be duly collecled : For it is certainly of 
 great Importance to Medicine, that the genuine 
 efifential Oils of Vegetables fnould be well di- 
 ftinguifhed from the adulterated, becaufe capable 
 of producing extremely different Effeds in the 
 Body ; a Confequence little regarded by the frau- 
 dulent Adulterator. 
 
 E X P E R I M E N T 111. 
 
 A Method of verifying Empyreumatic Oils, 
 
 Empyreu- 3 1 . It was obfervable in our dry Diftillations 
 Tnatic Oil of Wood a)^ Wormvvood ^), and Bone rj, (^c, 
 f^metned. always came over a grofs, fetid, empy- 
 
 reumatic Oil, of a naufeous Smell, difagreeable 
 Colour, and abominable Talte. To redify this 
 Oil, we took two Pounds thereof, and w^afhed 
 it well by the repeated Affufiou of hot Water, 
 and ftirring them well together, till at length 
 the Water came away confiderably pure; where- 
 by the Oil was rendered lefs naufeous both to the 
 Smell and Tafte : Then fecting it in an open Vefifel 
 over the Fire, that it might difeharge the Water 
 lodged therein by the Wafiiing, we afterwards 
 put it into a Glafs Retort, and drev/ it over in 
 a Sand Heat; whereby it left behind a black, 
 
 a ) See Le8. II. Exp^ III. 
 
 b) SteLebl. VIII. Exp. 11. 
 
 /j See Lell. YHI. Exp. I. 
 
 feculent. 
 
275 
 
 of Oils and Salts. 
 
 feculent, or burnt crufty Matter, and became 
 more fluid, fweet, and mild. 
 
 32. If the Diftillation be repeated ten or T'heExpe- 
 
 twelve times, either in a frefli Retort Zfdflf 
 
 time, or in the fame, the Oil being conftantly 
 returned upon its own Faces^ or Ca-put mortuum ; 
 
 thefe Faces will every time increafe in Quantity, 
 fo as to leave the Oil purer and thinner, till at 
 length it becomes almoll as thin and fluid as Oil 
 of Turpentine, or Spirit of Wine *, being extreme- 
 ly volatile, tranfparent, and penetrating, but 
 (till of a hot, pungent Tafte, and a fomewhat 
 faint and difagreeable Odour. 
 
 33. This Oil, obtained from an animal Sub*^^-^- 
 je6t, particularly from Blood, has been lately 
 □fed in England^ as a Remedy for the Epilepfy, 
 
 Gour, and other obftinate Difeafes, under the 
 Name of Oleum animale. It was many Years 
 fince ufed for the fame Purpofcs in Germany Yet 
 doubtiefs it fhould not be given too freely as an 
 Internal : But, as an external Medicine, it may 
 
 be of Service in refolving hard# Tumours, re- 
 moving fixed Pains, for it is extremely pe- 
 netrating and difcutient. And on this Account 
 it might, perhaps, be ufed to Advantage in 
 feveral Arts that require a highly fubtilized Oil. 
 
 34. But it being chargeable to bring the grofs 
 empyreumatic Oils to this Degree of Purity and 
 Subtilty, many chemical Operators continue to 
 throw them away as ufelefs •, and the rather, 
 becaufe of that intolerably naufeous Smell and 
 Tafie with which they affed: all Things that they 
 couch, or come in the Way of. But as large 
 Quantities of thefe Oils are neceiTarily obtained 
 in the Diitillation of Harts-Horn, Blood, iFc, 
 
 . * See Hoffman. Ohfervat. Fhyjico. Chym. p, 58. 59. 
 
 T 2 it_ 
 
2']6 
 
 Lecture the Thtrteenth. 
 
 it may be worth trying, whether they cannot be 
 purified in a cheaper Manner than that above 
 defcribed : For Example ; By drawing them over 
 from Pot-Alh; or, what is ftill more profitable, 
 by digefting them therewith, fo as at length to 
 turn the Mixture, by Sublimation, into a vola- 
 tile, alkaline Salt, as good as that of Harts-Horn, 
 Blood, putrefied Urine, 
 
 And thus much for the Subje6fc of vegetable 
 Oils. We next proceed to vegetable Salts. 
 
 II. 
 
 Experiment IV. 
 
 ^'he Method of refining Sugar ; or bringing the fvoeet 
 Juice of the Sugar-Cane into a white^ dry^ and 
 folid Suhjlance, 
 
 Sugar re- We took fix Pounds of coarfe or black 
 
 Sugar, as it comes unrefined from the Sugar- 
 Colonies, and ^iflblving it, over the Fire, in an 
 equal Qiiantity of ftrong Lime-Water, we ad- 
 ded the Whites of four Eggs, v/hificed up into 
 a Froth, and ftirred the Whole v/ell together, 
 in order to clarify the Sugar, after the fame 
 Manner as Syrups are ufually clarified ; we then 
 boiled the Liquor to a higher Confiftence than 
 that of a Syrup, or till it would fhoot grainy 
 in the Cold. To make it do this the better, we 
 continued to add Lime-Water at feveral times 
 in the boiling. Having obtaine(J this Point of 
 Confifience, by the Sugar- Refiners called Proofs 
 we poured the whole into a Sugar- Baker’s Earth- 
 en Mould, flopping the Hole in the lower 
 End, and fetting the Mould in a moderately 
 warm Place, the Sugar, after fome Days, fet 
 hard, or hardened j then opening the lower 
 
 * . Orifice 
 
of oils and Salts. 277 
 
 Orifice of the Mould, we inverted the fharp 
 End into a little Pot, or Sugar-Baker's Receiver^ 
 and applied to the wider End, or on the Top of 
 the Sugar, a Mixture of Tobacco-Pipe Clay and 
 Water, made into a Kind of thin Pafte, or 
 pappy Subftance. And thus the Water quitting 
 the Clay, foaked through the Sugar, without dif- 
 folving the grained Part, and carried down with 
 it only the treacly Matter, lodged betwixt the 
 Pores of the Sugar ; which treacly Matter was 
 catched by the Receiver underneath. And thus, 
 by keeping the Clay frequently wetting, and 
 fometimes renewing it, all the Treacle was got 
 out, and a pure Eoaf of White Sugar left be- 
 hind *, which we afterwards dried in a w’arm 
 Chamber, and kept it in a dry place. 
 
 36. The chemical Hiftory of Sugar deferves 
 to be traced through all its Stages. The rip^cefsand 
 Sugar Canes are ground dov/n in a Mill betwixt 
 Iron Rollers, kept continually feeding ; fo that 
 the expreffed Juice runs in a conftant Stream, into 
 its proper Receiver, from whence it is foon com- 
 mitted to the firft boiling Pan, to prevent its 
 turning eager: there it is boiled, Icummed, and 
 cleared of its grofler and lighter Feculencies 
 that float a-top, and alfo drawn from its hea- 
 vier F^ces which' fall to the Bottom. And thus 
 the Juice is brought to a Kind of Mfllago^ or 
 Rob For the Juice of the Sugar-Cane, when 
 firfl: boiled down, is like the Rob of Malt, Rai- 
 flns, the boiled Juice of the Birch or Sycamore- 
 Tree, and would never appean.in the faline 
 Form of Sugar, without fome Contrivance to 
 feparate its herbaceous, feculent Parr, and a 
 particular Addition to give it a confiflent Form. 
 
 Both thefe Ends are anfwered by the Addition 
 
 T 3 
 
 * See Ua, X. Exp. III. 
 
 of 
 
278 Lecture the Thirteenth. 
 
 of Lime-Water : For the Rob of the Sugar-Cane 
 being of an acid and uncStuous Nature, the 
 Quicklime deftroys the prevalent Acidity, dif- 
 folves and feparates the grofifer un6luous Mat- 
 ter, and at the fame time, combining along 
 with the truly faccharine Part, gives a Iblid and 
 dry Confiftence. And fomething of this Elfebt 
 Lime-Water has in every frefh Boiling; fo 
 that by a prudent Ufe hereof the Sugar may, 
 after repeated Operations, or by boiling it over 
 again with more or ftronger Lime-Water, be 
 brought aimoft to a cryftaliine P'orm. And on 
 the Strength, Goodnefs, and Quantity of the* 
 fine Part of the Lime, thus introduced into Su- 
 gar, depends the Hardnefs, Whitenefs, and 
 ihining, rocky Refplendency of Loaf-Sugar. So 
 that the Perfection of the Refiner’s Art depends 
 in a great Meafure upon the prudent Choice of 
 his Lime, and the Management of his Lime-Water. 
 
 37. The treacly Matter feparated from the 
 Sugar, is colleded together and boiled, feum- 
 rned, and treated with Lime-Water again, to 
 obtain from it all the Sugar that it will afford 
 in a dry form. When no more can be procured 
 from it by the Sugar-Baker, it is then called 
 ^Treacle \ being before ufually termed Syritp^ 
 which it perfedlly refembles : ’ Jnfomuch that a 
 thorough Knowledge of the Art of preparing 
 Syrups^ w'ith the Effedls of their Different 
 Confidences, and their Dirpofition to ferment, 
 turn acid, or candy, and the bed Ways of 
 clarifying them, &c. may contribute to improve 
 the Art of Sugars ; and accordingly it appears, 
 that moft of the Improvements in the Refining 
 of Sugars have been owing to Apothecaries and 
 Chemifts. 
 
 38, Sugar, 
 
I of Oils a 7 id Salts. 279 
 
 38. Sugar, thus refined, and difcharged of 
 its fuperfluous oily Parts, is thereby rendered 
 dry, thirfty, or apt to imbibe aqueous Moifture 
 or Oil ; upon which Property depends that 
 ufeful Invention of Elaof ac char urns ^ occafionally 
 mentioned above by means whereof we are fur- 
 nifhed with a very advantageous Method of unit- 
 ing Oils with Waters, Wines, Spirits, or all 
 Manner of aqueous, vinous, or fpirituous Li- 
 quors ; fo that fuch Liquors may be altered in 
 their Flavours, and improved in their Virtues, at 
 I pleafure. For, by grinding a fmall Proportion 
 I of any eflential Oil with dry Loaf-Sugar, the 
 Oil is thus rendered mifcible with any of the 
 above mentioned Liquors, and at the fame Time 
 is no Way impaired, but rather improved in 
 its Efficacy. 
 
 39. And thus we are taught an extempora- 
 neous Method of making all thofe fimple and 
 compound Waters, whofe Virtues depend upon 
 the effential Oils they contain *, which is the Cafe 
 of mod fimple Waters, as thofe of Mint, Pen- 
 nyroyal, Nay, fome fimple Waters may be 
 procured in greater Perfedion by this Means 
 than by Diftillation, as it is commonly perform- 
 ed. Thus the fimple Water of Baulm, for In- 
 ilance, may be made better by means of the 
 El(eofaccharum^ of Baulm and pure Water, than 
 by fimple Diftillation, which in this Cafe brings 
 over but little of the eflential Oil. 
 
 4.0. And for compound Waters, they may be 
 thus made to greater Perfedtion than we ufually 
 meet with them. For if only the firft Part of 
 the eflential Oils that comes over be ground 
 with Sugar, and introduced into a very clean 
 Spirit, the Cordial Waters fo prepared will .be 
 
 ^4 
 
 * See L.a. XI. Exp. I, 
 
 no 
 
280 Lecture the Thirteenth. 
 
 no way inferior to thofe diftilled in the ordinary 
 Manner. And thus Cinnamon-Water, Clove- 
 Water, Nutmeg- Water, Citron- Water, Cfr. 
 which depend upon the Ufe of but one Ingre- 
 dient, may be readily made. And if compound 
 Waters are required from feveral Ingredients, 
 vve need only have a compound Elaofacckarum at 
 Hand. 
 
 41. Thefe El ^ofac char urns alfo, as they are 
 eafily made, either fimple or compound, in great 
 Variety, might help to improve the Art of 
 Cookery, as affording the Virtues of Aromatics 
 in a commodious Form, for feveral oeconomical 
 Occafions *, and may thus be carried the long- 
 eft Voyages without Danger of fpoiling, or of 
 having their Virtues impaired: an Inconvenience 
 to which the natural Spices, though ever fo well 
 cured, are liable. 
 
 42’ Again; A proper Set of thefe EUofac- 
 charums might afford a Variety of ferviceable 
 Medicines, that fnould have all the Qualities re- 
 quired in the beft ; that is, ihould be at once 
 fimple, parable, efficacious, and pleafant : For 
 
 as effiential Oils contain the fpecific Virtues of the 
 Subjeds, or thofe Qualities which conftitutc every 
 Plant the Thing it is, they are of Confequence 
 fome of the moft concentrated, powerful, refto- 
 rative, and reviving Medicines hitherto known. 
 
 Experiment V. 
 
 ^he Way of Refining Ear tar, 
 
 Tartar re- 43* Pounds of common white 
 
 fined, Tartar rt'duced to Powder, and put to it five 
 Gallons of fair Water, in an earthen Pan, and 
 fetting it over the Fire to boil, we in the mean 
 Time beat up the Whites of two or three Eggs, 
 
 and 
 
 < 
 
of oils and Salts. 281 
 
 and whifked them in among the Liquor, which 
 we afterwards fkimmed and drained *, then fet it 
 to fhoot in an earthen Veffel, in a cool Place, , 
 for two Days, at the Expiration of which we 
 found a Parcel of whitifh Cryftals (licking to the 
 Sides of the VeOTel. 
 
 44. This is a very troublefome and hconn^e* 
 
 Operation; for Tartar requiring twenty times 
 
 its own Quantity of Water to diffolve it, the 
 Veffels, the Fire, and the whole Apparatus, mu(t 
 of Neceffity be large to refine a fmall Quantity 
 of this Salt; which yet is nor fufficiently refined 
 at one Operation, though the Whites of the Eggs 
 take up much dirty, and light earthy Matters, 
 while the more ponderous fink to the Bottom upon 
 (landing. Hence the Operation mud be feveral 
 times repeated, before the Crydals will become 
 perfedlly white; which they will fcarce ever 
 do, if the Vefiel wherein the Operation is per- 
 formed be metalline ; and Velfels of Earth, 
 which this Salt does not corrode, being hard to 
 procure fo large as they are required for the Fur- 
 pofe, this adds to the Inconvenience. 
 
 45. It is true, for mod Ufes in Chemidry, Remedied. 
 unrefined Tartar will anfwer as well as the re- 
 fined , but for the Service of certain Arts, par- 
 ticularly Dying, it is required thoroughly puri- 
 fied : So that a more commodious Method of 
 refining it diould be endeavoured after, that we 
 might at lead be able to refine it in England^ as 
 
 well as they do in France. 
 
 46. Tartar is of a very particular Nature ; 
 being a folid and firm vegetable Salt, extremely 
 hard to dififolve in Water, as containing much 
 earthy and unduous Matters, which defend it 
 from the Adion of Water : Vv^hence we are di- 
 reded to fofeen the Body of this Salt, or loofea 
 
 its 
 
282 Lecture the Thirteenth. 
 
 its Texture, in order to its more commodious 
 Refinement. And this End may be obtained 
 by a prudent Ufe of Lime-Water, or a weak 
 Lixivium of Pot-Afh, or Salt of Tartar ; as in 
 the Making of tartarized Tartar where com- 
 mon Tartar is united with its own fixed Salt, and 
 rendered eafily foluble in a fmall Proportion of 
 Water. But there need not be fo much Alkali 
 ufed for this Purpofe, as to deffroy the Acidity 
 of the Tartar *, and if too much fhould happen to 
 be added, it may be mortified with Oil of Vi- 
 triol, fo as not to prejudice the Salt. 
 
 "The E Xpe- 
 rt r/ient per- 
 jeded. 
 
 47. But where an extremely pure and perfedl 
 Cream or Cryflal of Tartar is required, we re- 
 commend the ordinary Cryflals, or Cream of 
 Tartar, to be diffolved in Water, made highly 
 acid with redified Oil of Vitriol ; for if the 
 fuperfluous Humidity be afterwards exhaled, the 
 Tartar will thus fhoot into perfedly tranfparent 
 and beautiful Cryflals, without at all participating 
 of the Oil of Vitriol. And by the Help of thefe 
 Diredlions common Tartar may be refined in great 
 Perfedlion, and with no greater Trouble than the 
 more foluble vegetable Salts. 
 
 ijjss. 48. When the Powdered Cryflals of Tartar 
 
 are mixed with half their Weight of Salt of Tar- 
 tar, and diffolved together in boiling Water, they 
 make a very extraordinary neutral Liquor, or 
 Mevftruum ; and by Evaporation a neutral Sale 
 of very uncommon Properties. This Salt eafily 
 runs in a moifl xA.ir; and will powerfully alTift 
 in extradling the refinous or oleaginous Parts of 
 Vegetables, by being boiled with them in Wa- 
 ter. The aqueous Solution of this Salt will dif- 
 folve the tough Bodies even of Myrrh, Gum- 
 
 ^ See below § 48. 
 
 Lac, 
 
283 
 
 of Oils and Salts. 
 
 j Lac, and is much better fitted than Salt of 
 i Tartar for many of the fame Purpofes where 
 i that Salt is commonly employed. This neutral 
 ! Salt, or tartarized Tartar, is exxellent in healing 
 i Wounds, and cleanfing Ulcers : It is an agreeable 
 I and iliccefsful Purgative in hypochondriacal Cafes ; 
 I! and, diflblved in Water, makes a pleafant Kind 
 of Purging Water, Its Virtues and Powers, 
 
 I both as a Menftruum and a Medicine, feem 
 i not hitherto fufficiently known ; whence we re- 
 commend it to farther Experience. 
 
 Experiment VI. 
 
 The Method of Refining Nitre ^ or Salt-Petre, 
 
 49. We diflblved four Pounds of rough Nitre, 
 as it comes to us from the Indies.^ by boiling 
 in as much Water as would commodioufly fuf- 
 fice for that Purpofe ; then fet it to fhoot for 
 two or three Days in a covered Veflfel of Earth, 
 with Sticks laid acrofs for the Cryftals to adhere 
 to. Thefe Cryftals being afterwards taken out, 
 were drained and dried in the open Air. 
 
 50. This leems to be the beft and fimpleft 
 Method of purifying Nitre ; for thus, by its 
 own natural Property of cryftallizing, it fhoocs 
 pure from the Sea-Salt, or other Foulnefs that 
 is apt to mix among it. However, if the Nitre 
 prove unduous, it may be proper to add a little 
 lixivium of Pot-Afh, Lime-Water, or Allum. 
 And if by this Means it does not become fufti- 
 ciently pure for making the beft Gun-powder, or 
 Aqua Fortis^ it muft be diftblved again, and re- 
 cryftallized, in the Manner of our prcfent Expe- 
 riment ; which being repeated, with a larger 
 Proportion of Water than before, evaporating 
 
 flov/ly 
 
 
284 
 
 Hlpory 
 
 Nitre, 
 
 Lecture the Thirteenth. 
 
 flowly and fuffering the Salt to flioot in a mode- 
 rately warm Place, without the free AdmifTion 
 of the external Air, the Nitre will be obtained 
 in its utmoft Purity and Perfedion. It is judged 
 to be pure, when being thrown upon live Wood 
 Coals, it fulminates brifkly, and will then make 
 perfedt Gun-powder and Aq^ua Fortis, 
 
 51. The chemical Hiftory of Nitre is ft ill de- 
 
 fective. This Hiftory fhould fhew, by what 
 Means Nitre is procurable from all animal and 
 moft vegetable Matters : For there are many 
 
 Experiments and Obfervations which feem tq 
 prove, that Nitre originally proceeds from pu- 
 trified Vegetables ; that many uncorrupted ve- 
 getable Subjects contain it in a large Proportion ; 
 and that all animal Subjects contain a femivolatile 
 Nitre *, which may be rendered more fixed, or 
 like the common, by the Addition of Pot-Afh or 
 Qj^iicklime a). 
 
 52. To thofc difpofed to enter upon this ufe- 
 ful Enquiry, we recommed a full Knowledge 
 of the Methods now in ufe for procuring Nitre 
 from certain Earths that are dunged by Ani- 
 mal?, and putrefied Vegetables ; the fliorteft: 
 Ways of feparating the unCtuous Matter from 
 the Nitre, which occafions all the Difficulty ; 
 and a due Comparifon of the Procefs for pro- 
 curing and refining of Nitre with that for pro- 
 curing and refining of Sugar. There is Reafon 
 to believe, an Enquiry of this Kind might be at- 
 tended with fuch Succefs, as to fhew that Nitre 
 is not peculiar to any one Country, but obtain- 
 able in Plenty, wherever animal and vegetable 
 SubjeCls abound Ip). 
 
 o ) ScG Mr. Lemer/s Papers upon this Subjed in the French 
 Memoirs. See alfo Dr. Stub'i Legends no liijloties, 
 
 b ) See Glauber s Profferity of Germany, 
 
 Expert- 
 
285 
 
 Of oils and Salts. 
 
 Experiment VII. 
 ne Method of Making Pot^AJh, 
 
 53. Having burnt a Quantity of common Billet- Pot-A/I? 
 Wood to grey Allies, we took feveral Pounds 
 
 of thofe Allies and boiled them in Water, fo as 
 to make a very ftrong TJxivium^ or Lie, This 
 Lie we drained thro’ a coarfe Linen Cloth, to 
 keep out any black Parts of the half-burnt Wood 
 that might happen to remain in the Adies ; then 
 we diredlly evaporated this drained Lie in an 
 Iron- Pan over a quick Fire, alrnod to Drienefs. 
 
 We took out the Matter remaining at the Bot- 
 tom, and putting it into an Iron-Crucible, fet it 
 in a drong Fire till the Matter melted ; and then 
 immediately poured it out upon an Iron-Plate, 
 where it foon cooled, and appeared in the Form 
 of a folid Lump of Pot-Afli. 
 
 54. And much after this Manner is Pot-Afh 
 made in the large VN^ay of Bufinefs, for the Ser- 
 vice of the Soap-Boiler, Glafs-Maker, F'uller, 
 
 But according to the Difference of the 
 Wood or combudible Matter employed, with 
 the Manner of burning it, and conducing the 
 Procefs, different Kinds of Pot-Adi are pre- 
 pared. 
 
 55. There are certain faline Plants that yield And ap- 
 this Pot-Affi to great Advantage, as particu- plication, 
 larly the Plant Kali ; there are others that afford 
 
 it in lefs Plenty, and of an inferior Quality, 
 as Bean-Stalks, i^c. But in general, all vege- 
 table Subjedls afford it of one Kind or other, 
 and may mod of them be made to yield it tole- 
 rably perfedt, after the Manner of our prefent 
 Experiment \ even the Loppings, Roots, and 
 
 refufe 
 
286 
 
 Difft- 
 
 rence. 
 
 Lecture the Thirteenth. 
 
 refufe Parts of ordinary Trees, Vine prunings 
 
 56. But befides the Difference found in diffe- 
 rent Vegetables for producing this Salt, as fome 
 may naturally contain more or lefs of the faline, 
 oily, or earthy Principle, than others * ; an- 
 other Difference will arife from the Manner of 
 burning the Subjeft, according as that is done 
 with a greater or lefs Degree of Fire, or Admif- 
 fion of the Air. If a vegetable Subjedl be burnt 
 in a clofe, ftifling Manner, to a grey, or fome- 
 what blackifli or brown Afh, thefe Afhes thus 
 containing more of the Oil of the Subjed, will 
 afford a more unduous Salt, that eafiiy melts in 
 the Fire, and is better fitted for the ready mak- 
 ing of Soap. > But if the Subjed be burnt in the 
 open Air, fo that it have every Way free Accefs 
 thereto, the Afhes will be white, or contain no 
 Part of the Oil of the Subjed ; and thus the 
 Salt will difficulty melt in the Fire, and prove 
 fitter for the making of Glafs (where no Oil is 
 required) than of Soap. 
 
 57. A third Difference in Pot- Afh arifes from 
 the Length or Shortneis of Time it is detained 
 in the melting Fire; whereby it becomes either 
 of a grey, white, bluifh, or greeniffi Colour 5 
 grey or white if it be foon taken out ; and bluifh 
 or greenifh if long detained therein. And ac- 
 cording to thefe Differences Pot-Afn is more or 
 lefs (harp or flrong ; a longer Continuance in 
 the Fire always confuming the more unduous 
 Parts, and leaving the faline ones more naked : 
 provided no confiderable Proportion of Earth 
 remain mixed with the Salt, which in that Cafe 
 would foon be vitrified, or turn to Glafs, and 
 have no faline Property at all. 
 
 See Lc£l. VIII. fajjlm, 
 
 58. The 
 
Of oils and Salts. 287 
 
 58. The fixed Salts of all Vegetables, when Improve- 
 reduced to abfolute Purity, or entirely feparated 
 
 from the other Principles, appear to be one and 
 the fame Thing *, at leaPc not manifeftly to differ 
 Whence it fhould feem that, by a fuitable Ma- 
 nagement, good faleable Pot-Afh might be made 
 in all Places where vegetable Matters abound : 
 
 For if, by examining Rujfia Pot afh, for Ex- 
 ample, we find, that its fuperior Excellence de- 
 pends upon its being clear of Earth, or upon its 
 containing a large proportion of Oil, or fixed 
 Salt •, thefe Advantages mayi by properly regu- 
 lating the Operation, be given to Englifh Pot- 
 Afhes, fo as perhaps to render the latter as good 
 as the former. But where the Pot-Afh of any 
 remarkably faline Vegetable is to be imitated, 
 as that of Kali fuppofe, we would recommend a 
 prudent Sprinkling of the Subjedt with Salt or 
 Sea Water in the Burning. And by thefe Ways 
 properly diverfified, any Principle that is natu- 
 rally wanting in the Subjedl might be artificially 
 introduced, fo as to perfed: the Art of Pot-Afh, 
 on which the Art of Soap-making depends. 
 
 59. For to make Soap requires an intimate 
 Union of the Salt of Pot-Afh with Oil, orany^r/<?/ 
 vegetable or animal Fat. This Union in the 
 prefent Method of Soap-makihg is procured by 
 
 a tedious Operation, or by long Boiling a weak 
 Lie of Pot-Afh and Quicklime with the Fat ; 
 adding a fbronger and a v/eaker Lie occafionally 
 by degrees, till the Point requifite to the Perfec- 
 tion of the Soap is hit. 
 
 60. It might greatly contribute to fhorten this hn ro-ve- 
 Operation and eafe the Expence thereof, if a me:;t in 
 mechanical Motion or Engine were employed that Art, 
 ftead of Fire, to procure this intimate Union of 
 
 ' the 
 
 See Lea, VIII. 
 
288 Lecture the Thirteenth. 
 
 the Lie and Oil. And that fomething of this 
 Kind is pradticable appears from hence, that 
 if, for Example, half a Pint of the Soap-boiler’s 
 ftrongeft, or Capital Lie^ as they call it, be 
 brifkly fhook in a Phial, with an Ounce or 
 more of Oil-Olive, for half a Quarter of an 
 Hour,' and then the Phial be fudered to red, 
 there will, in a fliort Time after, be found a 
 folid Cake of tolerable Soap at the Top of the 
 Liquor *, and may be eafiiy preferved in that 
 Form by breaking the Phial, and rendered harder 
 by being expofed to the Air. 
 
 71. We could wifh that the Chemical Hijlory 
 Wpryof of Soap were extant; for it iliould feem that 
 many Advantages might be thence derived to 
 particular Arts and Trades. This Hiftory is a 
 Thing of larger Extent than will be generally ap** 
 prehended, as containing three large Branches ; 
 (i ) the Hiftory of Pot-AJh ; (2) the Hijlory of Oils 
 and Fats \ and (3^ the fever al Ways of uniting 
 them to advantage. 
 
 62. (i) The Hiftory of Pot-AJh would fhew 
 wherein the Superiority of the foreign Afhes, 
 particularly tho!e of Marjeilles., Caftile., Venice., 
 and Joppa., confifts ; why the Soaps at prefent 
 made in Fjtgland fall fhort of Perfedion ; and 
 pofhbly inform us of the Ways whereby even 
 Joppa Soap might be equalled in England. For 
 luch a Hiflory would trace out the real phyfical 
 Differences betwixt one Sort of Pot-Afh and 
 another, and the Ways of converting any one 
 of them into the reft fo as to fit them for the 
 Soap-boiler, Glafs maker, ^c. refpedively; it 
 would fhew how the rnildeft Pot-Afh is obtain- 
 able, for the more curious Soaps, and efpecially 
 for thofe intended to be ufed medicinally, i 3 c* 
 
 * Ste above, § 62 — 65, 
 
 And, 
 
i 
 
 Of Oils and Salts. 289 
 
 And, by the Way, there is Room to fufpc( 5 t that 
 a thorough Enquiry into this Subjcdt would 
 Ihew the Matter of all Pot-Alh to be the Mat- 
 ter of Nitre-, or that all the Vegetables which 
 yield Pot-Afli by Calcination.^ might be brought 
 to afford Nitre by Putrefaffion \ or that Pot-Alh 
 is nearly the fame Thing, both in Nature and 
 Subftance, witli fixed Nitre *. 
 
 63. (2) The Hiflory of Oils and Fats would 
 alfo lliew how one Sort might be converted into 
 another, or hard animal Fats into liquid Oils, 
 and liquid Oils into folid Fats, by digefting 
 Oils with certain coagulating Acids, how 
 all the foreign folid Oil-Soaps might be imitated 
 in England-^ and how a great Variety of liquid 
 Soaps might be prepared for many different Pur- 
 pofes ; the Foundation of the Thing entirely 
 depending upon the Ufe of a highly fubtilized, 
 and thin vegetable Oil. 
 
 64.. (3) The Hiftory of uniting fixed vegetable 
 Salts with OiU might deferibe feveral Machines 
 for the Purpofe-, whereby many Tuns of Soap 
 fhould be readily made by Means of Mills, 
 wrought by the Wind or Water; and this ei- 
 ther with or without Fire. It might alfo inform 
 us of feveral Menftruums., or conne fling Mediums^ 
 which fhould, either alone, or with little AT 
 fiftance, procure an intimate Union. And that 
 fomething of this Kind is practicable, we are 
 affured by particular Experiments. 
 
 AXIOMS and CANONS. 
 
 I. We learn from the foregoing Enquiries, 
 that large Quantities of Oil may lie concealed 
 
 * 5ee Glauber s Profperity of Germany ; and M, Lemery\ 
 
 Papers upon 'Nitre in the French Memoirs. 
 
 u 
 
 in 
 

 290 Lecture the Thirteenth. 
 
 in Bodies apparently dry ; where neither the 
 Eye, nor any of the Scnfes, can perceive the 
 ordinary Signs of Oil a'). 
 
 2. That Oils gained by ExprefTion are apt to 
 turn rancid, and become unwholfome, by Heat : 
 Whence they fhould always be kept cool, and 
 not be drawn by the Means of Fire, if intended 
 for curious or internal Ufes. a). 
 
 3. That much Oil may be feparated by boil- 
 ing Water from Subjedls that have already 
 tek the utmofl: Force of the Prefs : Whence an 
 Eye fhould be had upon the Cakes of Lint-feed^ 
 Muftard-feed, for obtaining a farther Oil, 
 after they have been once fqueezed a), 
 
 4. That the oily Subftance of Nuts, Almonds, 
 and the like vegetable Subjects, is foluble in 
 Water, by bare Triture, into a vegetable Milk, 
 having a great Affinity with the Milk of Ani- 
 mals a). 
 
 5. That exprejjed Oils may be readily changed, 
 or improved, in their Colours, Takes, and 
 Odours V fo as that any one of them may afford 
 a great Variety of apparently different Kinds a), 
 
 6. That aromatic Vegetables yield an ejfential 
 Oil by Dikillation with Water; which Oil con- 
 tains the effential Or fpecific Take, Smell and 
 Virtues of the Subject b). 
 
 7. That the native Spirits^ or fine odoriferous 
 Parts of Vegetables, are readily imbibed, and 
 long preferved, by expreffed vegetable Oils a). 
 
 8. That the Difference betwixt the artificial 
 and 7 iatural effential Oils of Vegetables^ depends 
 upon the different Fixednefs or Volatility of their 
 diredt unckuous Parts b) : Whence we are diredl- 
 ed to a Way of introducing the native Spirits of 
 
 • 
 
 a) Exp. L 
 
 b) Exp. Jt 
 
 Plants 
 
Of oils and ^alts. 
 
 Plants into finer or lighter Oils than the common 
 exprefTed Kinds j fo as perfectly to imitate, or 
 exceed,* the natural eiTential Oils. 
 
 9. That there are fure Methods of difcove^f- 
 Ing feveral fraudulent and abufive Kinds of Ad- 
 iikeration in ejfentml Oils •, but that a more cu- 
 rious Adulteration is pradticable, fo as to elude 
 the common Trials a)\ 
 
 10. That every ejfenti'dl Oil has its determi-^ 
 hate fpecific Gravity : Whence, if a Table of 
 their fpecific Gravities were formed, from a 
 known genuine Set, fuch a Table might be of 
 Service in detedfing the Frauds or Debafements 
 frequently pradtifed in thefe Oils a). 
 
 It. That feveral Cautions are required th ex- 
 tradf the ejfential Oils of aromatic Indian VegC” 
 tables to Advantage ; which Cautions being du- 
 ly obferved, fuch Oils may be obtained in Eng- 
 land^ perhaps as perfedl as in the Indies a), 
 
 12. That a highly attenuated Oil is,- by re- 
 peated Redtifications, obtainable from the grofs^^ 
 fetid, and empyreumacic Oil of vegetable and 
 animal Subjedls b), 
 
 13. That the grofs, empyreumatic^ animal 
 Oils may, by Digeftion with fixed Alkalies^ af- 
 ford volatile Salts b). 
 
 14. That the Matter of Sugar is, originally, a 
 Vegetable Juice, ^ apt to grow four with Heat, 
 and not reducible by bare Boiling to folid Sugar, 
 but only to a mellaginous or treacly Subfiance c). 
 
 1 5. That many other vegetable Juices, as par- 
 ticularly thofe of the Birch and Sycamore Trees^ 
 the Rob of Malt, of Raifins, are convertible 
 into good Sugars, by the fame Means that are 
 tifed in the ordinary Sugar-making c). 
 
 a) Exp. II. 
 
 b) Exp, m. 
 
 t) Exp. IV, 
 
 TJ ^ jg. Thai 
 
 
2Q2 Lecture the Thirteenth. 
 
 j 6. That the Art of refining Sugar, fo as to 
 make it rocky, perfectly white, fpangly and 
 refplendent, principally depends upon a prudent 
 Choice and life of Lime-Water a . 
 
 17. That refined Sugar renders ejfential Oils 
 inftantaneoufly mifcible with Wines, Water, 
 and Spirits •, fo as to afford a ready Means of 
 improving feveral Arts a] : Or that the proper 
 lntrodu 61 :ion, Ufc, and Application of EUofac- 
 charums^ may improve the Art of Diflilhng, 
 Pharmacy, Wines, Cookery, and Medicine d), 
 
 18. That the troublefome Art of refining 'Tar- 
 tar may be fhortened and improved by the Ufe 
 of Alkalies and Oil of Vitriol b). 
 
 19. That Tartar is convertible into a very dif- 
 ferent Salt, by being united with its own fixed 
 Salt ; fo as hence to become a powerful Men- 
 ftruum, and a valuable Medicine ^). 
 
 20. That Cryffallization, once or twice re- 
 peated, is a fure Method of refining Nitre, or 
 Salt' Petr e r). 
 
 21. That 'Nitre is not originally a foffil,' but 
 a vegetable Salt *, and thence to be found in ani- 
 mal Subjedls d), 
 
 22. That a full Enquiry into pradficable Me- 
 thods of procuring Nitre dire6Hy from vegetable 
 and animal Subjeds, may be attended with Suc- 
 cels d)^ 
 
 23. That ferviceable Pot-i\fh may be made 
 in any Place that abounds with vegetable Sub- 
 jedfs e\ 
 
 24. That the Art of making Pot-Afh is im- 
 proveable by chemical Knowledge, to the Ad- 
 vantag;e of the feveral Arts thereon depend- 
 ing «r). 
 
 Exp. IV. h) Exp. V. 0 Exp, VI. d) Exp. VI. 
 and Vll. e) Exp, VII. 
 
 25. That 
 
of Oils and Salts. 293 
 
 25. That in particular, the Art of Soap- 
 making may be brought to much greater Per- 
 feflion in England.^ by Means of a mixt chemical 
 and mechanical Enquiry ^). 
 
 LECTURE XIV. 
 
 CONTAINING 
 
 Attempts to illu/lrate and improve the Buji^ 
 nefs of Colours, Dyes, and Stains. 
 
 i. /'^UR prefent Bufinefs is to difcover the The Suts- 
 Means of producing, varying, chang-^^^^^* 
 ing, and deftroying the Colours of Bodies ; with 
 a View to improve the feveral Arts that depend 
 upon the Ufe of Colours,, Dyes, and Stains h), 
 
 2. This we fhall endeavour to perform by The 
 Means of Experiments, firft upon Light, and Means. 
 then upon felecled Subjecfls of the vegetable, 
 animal, and mineral Kingdoms ; in order to find 
 
 out the phyfical Caufes of the Effeds produced. 
 
 3. The firji Experiment therefore will ihtw., The Heads 
 that common Light is feparable into kvtV2i\of the Ex- 
 Colours : The fecond will be colledtive, or afford 
 
 a Variety of Inftances to prove that the Colours 
 of Bodies depend upon a certain Difpofition of 
 Parts, fitting them to refled: the differently 
 
 a) Exp. Vir. 
 
 The prefent LeSlure was not publicldy read, as the reft 
 w’ere ; a clear fun-fhiny Day, which the Experiments require^ 
 not happening at the Time. 
 
 U3 
 
 coloured 
 
#94 
 
 'J Uc^difig 
 Experi- 
 2f2€»t, 
 m)ith the 
 frifn;. 
 
 fhe frlf. 
 
 piaiic Co- 
 Jo^rs. 
 
 Eiit far- 
 ther refol 
 
 Lecture the Fourteenth, 
 
 coloured Rays of Light : The third principal 
 Experiment will exhibit the Method of obtain- 
 ing chofe vegetable Colours commonly called La- 
 ques : The fourth will teach the Way of preparing 
 a certain animal Colour called Prujfian Blue : 
 and the fifth will fhew the Way of preparing a 
 metalline Colour, for tinging Glafs red, 
 
 ExpePvIment L 
 
 fhat the Rays of Light are compounded^ and fepa- 
 rahle into Jeven dijlindl ’Kinds or Orders of Light. ^ 
 on which all Colours depend. 
 
 4. (i) Having darkened a Room, by fhutting 
 np all the Windows, and bored a fmall Hole in 
 a Shutter oppofite to the Sun ; if a Glafs Prifm 
 be now properly placed againft this Hole, v/e find 
 that an oblong and varioufly coloured Image of 
 Light will be thrown upon the Cieling, or far- 
 ther Wall of the Room. (2) If this Image of 
 Light be carefully examined, it will appear to 
 (confift of feven diftindt Colours, or different 
 vivid Lights, which are conffantly found in the 
 fame Order ; viz. Red in the firff Place, Orange 
 in the feepnd, Yellovv in the third. Green in 
 the fourth. Blue in the fifth, Violet in the 
 jfixth, and Indigo in the feventh : But a flight 
 View diftinguifhes only five principal Colours ; 
 viz. Red, Yellow, Green, Blue, ’ and Violet.' 
 (3) If thefe feveral coloured Lights be fepa- 
 rately received upon anpther Prifm, in the 
 fame Manner as the Stiffs Rays are by the firft, 
 they fuffer no farther Divifion, or Refolution, 
 but remain invariably the fame : And this they 
 do whatever figured Glafs, Cryftal, or Diamond 
 be made ufe of. (4) But if the whole Number 
 
of Colours. 
 
 29S 
 
 thefe differently coloured Rays be received, Compsund 
 from the firft Prifm, upon a Lm, or double 
 convex Glafs, in the Room, they are thus 
 blended together again, and may be thrown up- 
 on Paper, or any other Body, placed at a due Di- 
 ftance, fo as to form a Spot of white and bright 
 Light in the Focus of the convex Glafs. (5.) If OhjeBsaf.^ 
 the red Rays be feparately received by an opake/«^^^^^ 
 white Body, that Body appears to be red; 
 the yellow Rays be feparately received in the ^ ^ 
 
 fame Manner, by an opake white Body, the 
 Body appears to be yellow ; and fo of the othe^ 
 
 Colours refpedively : A red Body appears more 
 vivid, or intenfely red, in the red Light ; a 
 blue Body more vivid, or intenfely blue, in the 
 blue Light, ^c.. But all coloured Bodies appear 
 more dead or languid in Lights of different Co- 
 lours from their own ; as a red Body in a blue 
 Light, 
 
 5. This general Experiment is the Foundar v 
 tion of Sir I[aac Newtorfs Dodtrine of Light and 
 Colours *; and may fhew, (i.) that the Sun’s Light a 
 Light is not a fimpie Thing, but compounded of Compound 
 feven different Orders of coloured Rays ; all 
 which being exquifitely blended together, eon- 
 ftitute a perfedly whitefiLight : (2.) That thefe Of fenjen 
 feven Orders of Ray:# are differently refran- Colours, 
 gible ; that is, differently difpofed to be turned 
 out of their Way, in "paffing from one tranfpa- 
 rent Body into another ; the red Rays leaft, the 
 Violet molt, and the reft in their Order as men- 
 tioned above : Which . is the phyfical Reafon 
 of the Divifion of Light into thefe feven Or- 
 ders of Rays, and that there are no more 
 than feven original Colours of Light : (3.) That 
 Bodies appear of the fame Colour with the 
 
 f Sc3 his Optics, paffm. 
 
 y 4 
 
 Order 
 
296 
 
 Ihe Co- 
 lours of 
 Bodies 
 from 
 
 Light. 
 White and 
 Black no 
 Colours, 
 
 Colours of 
 
 Bodies 
 
 whence. 
 
 ^he tex- 
 ture of Bo- 
 dies chan- 
 gedbj Lri- 
 tare. 
 
 Lecture the Fourteenth. 
 
 Order of Rays they refled^, or turn back, in^ 
 to the fame Medium from whence they were 
 received : (4.) That White and Biack arc no 
 true Colours ^ but White an equal Refledion 
 of all the original Colours, and Black the Ab- 
 forption of them all *, for if they were returned, 
 either mixed or unmixed, Whitenefs, or fome 
 of the feven original Colours of Light, and not 
 Blacknefs, would appear : (5.) That the Variety 
 of Colours in natural Bodies proceeds from their 
 differently refie^Hng or refracting the Rays of 
 one, two, or feveral Orders, more than the reft. 
 Thus the Bodies denominated red chiefly re- 
 flect the red Order of Rays ; thofc denomi- 
 nated blue Bodies chiefly refledt the blue Rays 
 of Light ; and are thence faid to be red, blue, 
 ^c. And all the mixed Colours of natural Bo- 
 dies arife from their refledling two or more 
 Orders of Rays together, and abforbing or 
 ftifling the Reft. 
 
 Experiment II. 
 
 Or, colleBive Inftances to Jhew that Tranfparenryy 
 Whitenefs,^ Blacknefs,, and Colours,, as confidered 
 in Bodies., depend upon certain particular Struc- 
 tures, L e% Hires, or Arrangements of the Parts of 
 Bodies ; differently difpofmg them to tranfmit, re- 
 fiedl, refraA, or ahforb the Rays of Light, 
 
 6. (i.) Glafs, Cryftal, Diamonds, Nitre, Bo- 
 rax, and other tranfparent folid Bodies, lofe 
 their Tranfparency, and appear white, upon 
 their being reduced to Powder ; that is, by a bare 
 Alteration of their grofs Texture, or a Ample 
 Redudlion to fmaller Parts, fo as to make them 
 reflect many of the Rays of Light which they be- 
 fore tranfmitted. And the fame holds of the Whites 
 of Eggs whifked up to a Froth, frothy Water, c. 
 
 7. Black 
 
Of Colours. 297 
 
 7. Black Talc, by being made red hot in the By lire. 
 Fire, is turned of a Gold Colour ; Syrup of 
 Violets, by a boiling Heat, lof«s its beautiful 
 Violet Colour, fo as at length to become pale, 
 
 or coloLirlefs •, white Loaf-Sugar, being barely 
 melted over the Fire, without Water, immedia- 
 tely changes its Whitenefs, and becomes brown, 
 or, by a longer Continuance, black ; fo that a 
 fingle Grain of this black Subftance will tinge a 
 Pint or a Quart of fair Water, or colourlefs 
 Brandy, of a beautiful yellow, brown, or draw 
 Colour ; for which Purpofe it is ufed by Diftil- 
 lers, and others d). 
 
 8. All the finer coloured Flowers, as Violets, By the Air. 
 Carnations, Rofes, lofe their Colours ba- 
 rely by being expofed to the open Air for any 
 
 long Time ; fo as at lad to appear perfectly dif- 
 charged, or white ; as if they had been expofed 
 to that particular Difcharger of Colours, the 
 Fume of burning Brimdone. And the fame 
 is remarkable of the finer or lighter Kinds of 
 Colours in Silks, or the light Blues, Yellows, 
 and Reds, particularly the light grain-coloured 
 Silks ; all which Colours are gradually changed, 
 difcharged, or abolifhed, in wearing, or by the 
 Silks being long expofed to the Acdion of the 
 Air h). But the Scarlet Colour is more fixed and 
 durable. And, in general, the deeper any Co- 
 lours are, the more fixed and durable they 
 prove ; as being thus not Shades, as the Pinks, 
 light Blues, idc. are, but true Colours, corre- 
 fponding to the original Colours of Light. Add 
 to this, that Dyers condantly find their Colours 
 prove brighted, or drike to the bed Advantage, 
 when the Air is clear h). Ladly, the blue efien- 
 
 tiai 
 
 m) See Le5l. IT. and XII’, 
 U) See LeCl. III. paj/im. 
 
298 Lecture the Fourteenth, 
 
 tial Oil of Camomile-Flowers lofes its Colour, 
 and changes to a dirty Green, by being expofed 
 to the Air. 
 
 Py Water, p. Different Waters ftrike different Colours 
 
 with the fame tinging Ingredients. Thus irony 
 Waters turn black, or inky, with Galls, Green 
 Tea, ^c. And Dyers find fome certain Wa- 
 ters more proper for their Purpofes than others. 
 And, in general, the pureft and lighteft Waters 
 ftrike the beft Colours with Dying -Stuffs, And 
 hence it is that fuch Waters as have, by long 
 ftanding, putrified, or fermented, and purged 
 themfelves, or been filtred thro’ the common 
 Fiitring-Stone, or Sand, are found to extradt 
 and communicate Colours tp the greateft Ad- 
 vantage 
 
 Py Salts, JO. Salts having a Power to alter the Textures 
 of Vegetables, do confequently produce Changes 
 of Colours therein. Thus moft Flowers, whe- 
 ther blue or red, as Violets, Rofes, &c. turn 
 green with Alkalies *, but Violets turn red, and 
 jed Rofes have their native Rednefs greatly high- 
 tened by Acids, So again, the yellow Roots of 
 Rhubarb, Turmeric, are hightened, or made 
 redder, by alkaline Salts, 
 
 fhe Tex Metals have a ftrong Texture in their 
 
 ture of metalline Form, fo they preferve their natural 
 Metals left Colours durably, unlefs corroded or diffolved 
 alterable, particular Menftruums •, after which, 
 
 their Solutions ftrike particular durable Colours, 
 or afford the ftrongeft Siam. 
 
 12. Iron diffolved in ftale Small-Beer gives the 
 beautiful Yellow ufedin Callico-Printing •, when 
 fublimed with Sal-Armoniac it alfo affords ^ 
 Yellow. And the common Iron-Moulds made 
 by Ink, are owing to the Iron diffolved in thp 
 
 f Sfse Lect, V. fajjlm. 
 
 Copperas^ 
 
1 
 
 Of Colours, 
 
 Copperas, whereaf the common BIa,ck Writing- 
 ink is made. 
 
 13. Copper melted with Zink appears of d. Colter 0 
 .Gold Colour ; diffolved in Aqua-Fortis it affords 
 
 a beautiful Green •, and in any urinous Spirit, 
 a beautiful Blue \ and the Solutions may be re- 
 duced to dry Colours, by Cryffallization, or 
 Evaporation. The fame Metal precipitated 
 with common Salt, out of Aqua-Fort, s,^ gives the 
 Turquoife Colour to white Glafs, when m.eited 
 therewith. 
 
 14. Tin, a white, or colourlefs Metal, Tin. 
 fords a light blue Colour, by being fluxed with 
 Antimony and Nitre. The fame Metal is ne- 
 ceffary in ftriking the Scarlet-Dye, with Aqua- 
 Fortis and Cochineal. Its Calx turns, by ffrong 
 Fufion, to a Glafs of the opal Colour. 
 
 15. Lead, being corroded by the Fumes of 
 Vinegar, makes the fine White called Cerufe.^ 
 and the white Fucus called Magifiery of Lead\ 
 being calcined in a ffrong naked Fire, it be- 
 comes Minium, or Red Lead 5 and this melted 
 into Glafs with Sand, is the Foundation of the 
 Art of imitating all the coloured Gems : For 
 this Glafs jtfejf will refemble the Hyacinth, 
 and by the Addition of prepared Gold and Tin, 
 the Ruby a) ; the Sapphire with Cobalt, the 
 Emerald with Iron and Copper, the A methyl]: 
 with Gold, and the Granat with Iron, fAc. b). 
 
 16. Silver, another white, or colourlefs Metal, 
 being dilTolved in Aqua-Fortis.^ if Chalk is put 
 to the Solution, turns ot a beautiful Purple, or 
 Amethyft Colour : And its own Solution, tho’ 
 pale as Water, durably ftains the Nails, the 
 Skin, the Hair, and other animal Subftances^ 
 brown or black. 
 
 a) See below Exp, V. See NerEj Art of Glafs ; an4 
 Mr. Boyle's Philofopbical Works^ paffim, 
 
 j 7. Quick- 
 
300 Lecture the Fourteenth. H, 
 
 s^ick- ij, Quickfilver mixed with Brimftone makes ‘| 1 '* 
 filler, ^ black Mafs ; and this, by Sublimation, affords ;; i* *" 
 the beautiful red Pigment called Cinnabar^ or j. 
 Vermillion : and the Solution of Quickfilver, 
 being precipitated with common Salt, yields a v' j' ^ 
 fnow white Powder ; which alfo turns black, by , ^ |l 
 being mixed with Sulphur. ^ !| 
 
 Cold, 1 8. Gold,, diflblved in Aqua Regia,, affords a ; ! \ 
 
 fine yellow Liquor ; which ftains animal Sub- ji| 
 fiances beautifully purple : And if the Solution ^ 
 be fufficiently weakened with Water, and mixed 
 with a Solution of Tin, a fine red or purple 
 Powder may be thus obtained for ftaining Glafs 'I: 
 moft beautifully red a), | 
 
 Minerals, 1 9. Many mineral Subjedls are natural Pig- S 
 ments ; as native Cinnabar, Ochre, Black Lead, S 
 but particularly the yellow Earth called ® 
 Light Ochre,, found in Shottover Hills, which is S 
 ufed native as a light Yellow, and by Calcina- 
 tion makes a light Red. This Colour England ®|; 
 fupplies Italy with , and Le Gar would frequently 
 fay he had been no Painter without it h'). 
 
 Experimental Inftances of Colours produced^ deftroyed^ 1 
 and regenerated upon fmple Mixture, * 
 
 Acohurlefs 20. (i) Put dry red Rofe-Leaves into Spirit 
 Liquor af- Qf Wine, and, by (landing a little therein, the 
 ^Catursb' R^fe-Lcaves will lofe their red Colour, without 
 Mixture^, manifeflly tinging or altering the Liquor ; then 
 add a little Oil, or Spirit, of Vitriol thereto, 
 and the Liquor will appear of a red Colour. 
 
 But if a little alkaline or urinous Spirit be poured 
 to the Mixture, the red Colour prefently chan- 
 ges to a Green *, which, by the Addition of a 
 
 a) See hereafter, Exp, V. 
 
 It) See below, Lxp. V. ^ 07, 
 
Of Colours. 30 1 
 
 little more Spirit of Vitriol, turns to a red Co- 
 lour again. 
 
 21. (2.) Make a flight Infufion of bruifed Galls Cohurkfs 
 in Water, fo as not to difcolour the Water *, filtre ^ 
 the Infufion ; make alfo a weak Solution 
 
 Green Vitriol in Water, and filtre the Liquor, fo 
 that they may both appear pellucid : Thefe Li- 
 quors being now mixed together, an inky Black- 
 nefs will immediately arife ; but if a little Oil 
 of Vitriol be added to the Mixture, the Black- 
 nefs will, by Degrees, totally vanilh, and the 
 Liquor appear pellucid again ; tho’ the Black- 
 nefs may be recalled by the Addition of a little 
 Salt of Tartar. 
 
 22. (3.) If a little bruifed Camphire, which is Amihlte 
 a very white Subftance, be put into pellucid 
 
 of Vitriol, and the containing Glafs be fhook^^^Jj^ 
 for fome Time, the Camphire will diflblve, tumU into 
 
 gradually change the Mixture to a Brown, and Blacknefs. 
 at length to a full Black. But upon the Addi- 
 tion of fair Water, the Blacknefs entirely va- 
 nifhes, and the Camphire rifes to the Top in its 
 priftine Form, and native Whitenefs *. 
 
 23. (4.) If the Shavings of Lignum Nephriti- a Liquor 
 cum be infufed for fomeTime in cold Water, and differently 
 the clear Liquor be decanted into a clean Glafs, ^ 
 and viewed from the Light, the Liquor will ap- ffjZZedZ 
 pear of a beautiful Blue ; but if viewed towards 
 
 the Light, of a Yellow. If a little Spirit of Its Colour 
 Nitre be put to this Liquor, it lofes its Power 
 of refledfing the blue Rays ; but the Addition of^^ZZdhy 
 a little Oil of Tartar, per deliquium^ recovers that Mixture, 
 Power again. 
 
 24. (^.) If Logwood be infufed in Water, \ti^^d chan- 
 gives a red Colour ; which, upon the Addition. 
 
 * It is remarkable, in this Experiment, that the ftrong 
 Scent of the Camphire is abfolutely wanting in the black So- 
 lution ; but recovered upon the Addition of the Water. 
 
 of 
 
go2 Lecture t rt e Fou rte e n th., 
 
 of a little Spirit of Urine, turns to a fine Purple : 
 But this may be changed to a dilute Red, by 
 dropping in a little Spirit of common Sait. 
 
 25. ( 6 .) An Infufion of Brazil Wood, of C6- 
 chineal, in 'Water, is much hightened in its red 
 Colour, by the Addition of Spirit of Urine ^ 
 and lowered or turned paler by the Spirit of 
 Salt. 
 
 26. (y.) If Spirit ot Wine be digefted uport 
 recent Camomile-Flowers, and diliilled over 
 from them in a Glafs Retort, the Spirit will thus^ 
 acquire a beautiful blue Colour, which may be 
 made deeper by being drawn over again from 
 frefii Flowers. 
 
 27. (^.) A beautiful blue Tinflure being made 
 
 by digefting Spirit of Urine upon Filings of 
 Copper, the Addition of a little Oil of Vitriol 
 entirely deftroys the blue Colour ; as a little Spi- 
 rit of Salt turns it to a Green. ^ 
 
 28. ('qj Pellucid Oil of Vitriol being mixed 
 with pellucid Oil of Turpentine, or the effential 
 Oil of Anifeeds, or more particularly with Oil 
 of Cloves, they turn thereupon into a thick, red 
 Balfam. And fo again, if a pellucid common 
 Oil be, by Means of a little Wax and continued 
 Triture, gradually mixed with fair Water, they 
 unite into a very thick, white Subftance, Balfam,' 
 or cold Cream. 
 
 29. (10.) Oil of Vitriol being difcrlled over 
 from Quickfilver, leaves a white Powder be- 
 hind *, to which if Water be poured, the Powder 
 prefently becomes of a beautiful Yellow. 
 
 30. (ii.) To a Solution of Quickfilver iit 
 Spirit of Nitre, add Spirit of Urine ; and a white 
 Powder will be precipitated : To another Parcel 
 of the fame Solution add Oil of Tartar per deli- 
 quium^ and a yellow Powder will fall to the Bot- 
 tom : To a third Parcel of the fame Solution 
 
 add 
 
 Red Co- 
 lour s hij^h- 
 i tried and 
 lo'^ 'tred b) 
 Mixture. 
 
 Apeliucid 
 Liquor 
 maae blue 
 by a bite 
 Body* 
 
 A blue Co- 
 lour def- 
 troyed by 
 Mixture. 
 
 Tellucid 
 Liquors 
 made red 
 by Mix- 
 ture, 
 
 A niohite 
 Ponvder 
 made )el- 
 louj by 
 Mixture. 
 
 ^he fame 
 Solution 
 aff'ordirtg 
 differently 
 coloured 
 Precipi- 
 tates. 
 
of Colours. 363 
 
 add Spirit of Urine, and the Precipitate obtain- 
 ed will be of a Flclh-Colour. 
 
 31. (12) If a clean new Pen be dipped inLimpiJInk 
 Spirit of Vitriol, and the common deep 
 
 Paper be wrote upon therewith, the Letters ap- 
 pear of a very bright and beautiful Red : And,* 
 in the fame Manner, pellucid Spirit of Salt ftains 
 a black Hat red. 
 
 32. (13) A pellucid Solution of Saccharum invifihk 
 Saturni in Water, being wrote with, becomes InL 
 invifible upon the Paper, when dried : But the 
 
 bare Fumes of another tranfparent Liquor^ viz. 
 an Infufion of Quicklime and Orpiment in Wa- 
 ter, will foon render the invifible Writing black 
 and legible. And thus thofe commonly called 
 Invifible or Sympathetic Inks are made. 
 
 33. ' (14) The volatile Sait of Sal- Ammoniac, ^ 
 a white Body, and the Cryftals of Copper, 
 
 green one, will, by Mixture, become Purple. Pulple. 
 
 34. (15) Salt of Steel, a green Body, zxi^AGreen 
 Sugar of Lead, a white one^ being mixed 
 
 ther, the Surface of the mixt Powder will ap- 
 
 pear red ; whilfl the internal Parts are of a dirty * 
 
 White. 
 
 35. (16) That original, and fimple, as well 
 as compound. Colours, are producible by Mix- 
 ture, appears from many Experim.ents. 
 
 36. (17) If the Sun’s Rays pafs thro’ X.'^QAGreex 
 Pieces of differently coloured Glafs, for Inftance, 
 
 a blue and a yellow Piece, laid upon each other, 
 and thele Rays be received from the Glaffcs 
 upon white Paper,' ^they then appear of a beau- Glafs. 
 tiful Green. 
 
 37. (18) It is common with the Dyers, toGreens’ 
 dye the Cloth firft Blue with Woad, and turn 
 
 that Blue into a Green by the Yellow CdW^di 
 Dyefs }Feed^ or Luteola. 
 
 38- (19) 
 
304 Lecture the Fourteenth. 
 
 Green from 38. (19) To a fine ycllow Solution of pure 
 abheand Gold, in Aqua Regia^ add a deep blue Solution 
 of Copper in Spirit of Urine ; and the Mixture 
 will appear green. 
 from Hue 39' (^°) ^lue and yellow Ammel, being 
 Gnd-^ellouo melted together, conftitute a green one 
 
 jyello'xv Li- 
 quor, 
 
 Ammel. 
 Many 
 Painter's 
 Colours by 
 Mixture. 
 
 Mixed Co- 
 lours may 
 make 
 
 White. 
 
 Flames of 
 
 different. 
 
 Colours* 
 
 green 
 
 40. (21) The Painters make a great Variety 
 of compound Colours, by mixing two, three, 
 or more different Colours together, either on 
 their Fallal., or on the Canvas. 
 
 41. (22) A Mixture of the feven original Co- 
 lours, or even five oi them, will make a White; 
 and the more perfedliy, the finer and more per- 
 fed: the coloured Bodies are. Thus, if a large 
 Top be painted on its upper Surface, one Part 
 red, another yellow, another green, another blue, 
 and another violet ; this Surface, whilfl the 
 Top is fpinning brifkly (fo that the Motion 
 fliall confound the feveral Colours, or make 
 them appear mixed to the Eye) will exhibit a 
 dirty Kind of Whitenefs. And in like Manner, 
 by mixing together Powders of different Co- 
 lours, as Vermillion, Orpiment, Indigo, Verdi- 
 greafe, &c. in proper Proportions, the compound 
 Powder will, in a firong Light, appear to be 
 white. And if differently coloured Flames 
 could be brought to mix, this Experiment might 
 be made in greater Perfedion. 
 
 42. (23) Flames are of different Colours, 
 according to the Bodies that produce them. 
 Thus the Flame of burning Camphire is white, 
 like the Focus of a Burning Glafs ; the Flames 
 of Spirit of W ine, and of Sulphur, are blue ; the 
 Flame of white Wax is white, inclining to blue ; 
 that of Tallow, white, but rather inclining to 
 yellow, &c. Whence proceeds the Difference 
 of the Colours of Bodies, as viewed by Day- 
 light, Candle light, Fire-light, fulphureous Light, 
 
 iAc* 
 
Of Colours. 305 
 
 ^c. And, for making Experiments to this 
 Purpofe, Oil might be impregnated with cer- 
 tain Metals, as particularly Copper and Iron, 
 by Triture, and Digeftion, fo as to exhibit 
 their particular Flames. 
 
 43. (24) The Prifmatic, or original ColoursT-^^f Prif- 
 may be imitated to confiderable Perfedcion inmaticCo- 
 Liquors, where the Parts of the tinging 
 
 ces are rendered extremely minute or fine. Thus^^^^ * • 
 a Solution of Cochineal in Spirit of Urine, view- 
 ed in a ftrong Light, alfords a mioft vivid and 
 beautiful Red*, a Solution of Copper in Spirit 
 of Urine, yields a glorious Blue; a Solution of 
 Verdigreafe in diftiiied Vinegar, is an excellent 
 Green *, a Solution of Gold in Aqua Regia^ 
 makes a fine Yellow ; an Infufion of Violets in 
 hot Water, affords an excellent Violet Colour, 
 
 Cfr. And from a thorough Acquaintance with 
 thefe Liquors, and the Methods of varying, 
 mixing, and heightening their Colours, many 
 Improvements in the Arts depending upon Co- 
 lours, Dyes, and Stains, might be rationally 
 expected. 
 
 44. (25) The foregoing Set of Experiments^^y«// ^ 
 not only confirms the former leading Experiment^^^ 
 made with the Prifm, but alfo Sir Ifaac 
 
 tori% general Do^irine of Colours : For it is hence 
 manifefl, that fright mechanical Alterations in 
 Bodies, produce, alter, or abolifh all Kinds of 
 Colours therein *, or that all the Colours of Bo- 
 dies are only original Colours of Light, diffe- 
 rently reflected, either in a fimplc or varioufly 
 compounded State, according to the particular 
 Difpofition, Texture, Mixture, or Arrangement 
 of the fmall Parts of the refieding Body, fo as 
 to afford that infinite V ariety of Colours we meet 
 with in natural and artificial Things. 
 
 X 
 
 E X P E R I- 
 
3o6 Lecture the Fourteenth. 
 
 Experiment III. 
 
 ^he Method of preparing the vegetable Colours called 
 Laques. 
 
 ^heLaque 45. Take a Pound of Turmeric-Root, redu- 
 offlurme- ^ed to fine Powder, three Pints of fair Water, 
 and an Ounce of Salt of Tartar ; put them into 
 a glazed earthen Vefiel, and let them boil to- 
 gether, gently, over a clear Fire, till the Wa- 
 ter appears richly impregnated with the Tur- 
 meric, or will ftain a Piece of white Paper beau- 
 tifully yellow ; then filtre the Liquor, and gra- 
 dually add to it a ftrong aqueous Solution of 
 Roch-Allum, till the yellow Matter is all curd- 
 led together, or precipitated : After this, pour 
 the Whole into a Filtre of Paper ; where the 
 aqueous Part will run off, and leave a yellow 
 Matter behind ; which being edulcorated, or 
 walked in the Filtre, by the repeated Affufion 
 of frefii Water, till the Water comes away in- 
 fipid, and afterwards dried, becomes the La- 
 que of Lurmeric^ or a beautiful yellow Colour 
 for Painting. 
 
 ‘The gene- 46, This Experiment fliews a general Me- 
 r*it of of obtaining a Laque from all the vege- 
 table Subjeds fitted to afford it : For in the 
 fame Manner may a red Laque be made from 
 Madder, Brazil, and many other dying Woods, 
 or tinging Vegetables. But where the Colour 
 of the Subjedl depends upon a very fubtil Tex- 
 ture, Mixture, or Arrangement of the Parts, 
 this Method deftroys, or at leafl: impairs, the 
 Colour ; as particularly in Violets, Red Rofes, 
 Carnations, So that it feems applicable 
 
 only to the tinging Vegetables of a fomewhat 
 ftrong and firm Texture, 
 
 47- In 
 
Of Colours. 307 
 
 47. In fome Cafes alfo a fimpler Procefs is'The parti^ 
 fufficient to obtain rich Laques particularly 
 
 that beautiful red one emphatically called Laque , ^stuTlai. 
 and from which the Name feems to be derived 
 to the reft. This red Laque is obtained barely 
 by boiling Stick-Lac in Water ; then filtring the 
 Deco6lion, and evaporating the fuperfluous Hu- 
 midity : For the beautiful red Colour adheres 
 to the Outfides of the Sticks broke off the Trees, 
 along with the Gum-Lac ; and readily communi- 
 cates itfelf to boiling Water As fome of this 
 tinging Matter likewife fticks to the Gum 
 itfelf, it is proper to boil them both together : 
 
 For the Gum does not prejudice the Colour, nor 
 diffolve in boiling Water : So that after the 
 Operation the Gum is as fit for the making of 
 Sealing-Wax, or other Ufes that do not require 
 the Colour, as it was before. 
 
 48. And much after the fame Manner is xh^itCarminei 
 extremely rich and beautiful red Colour called 
 Carmine prepared from Cochineal and a Solu- 
 tion of Tin ; for Carmine may be conceived as 
 
 no more than the Scarlet, or Bow-Dye Liquor, 
 concentrated, or reduced to what the Painters 
 call a Body. 
 
 49. Flow far our prefent Experiment may be 
 applicable to other Parts of the Materia tinfloria., 
 feems not hitherto well confidered. Doubtlefs^^^^^^^^^^’ 
 it might afford a great Variety of new Colour 
 
 by a proper Extenfion and Diverfification in the 
 Menjiruum and Method. For Example : If Red 
 Saunders be digefled warm in Spirit of Wine,, 
 
 * The tinging Matter adhering to the Sticks and Gum is 
 perhaps not a vegetable, but animal Subftance; fomewhat of 
 the Nature of Cochineal, and depofited in Form of an Excre- 
 ment, by a certain Kind of Bees, in the Indies. See a Paper 
 upon this Subjeft in the French Memoirs; fee alfo Mr. Boylt 
 Upon human Blood. Jbridgm. Vol. II, p 481. 
 
 X 2 
 
 the 
 
3o8 Lecture the Fourteenth. 
 
 AredRoJinxho, Menftruum acquires a deep red Colour; 
 
 ^Sa 7 n 7 ers drawn off by Diftillation, leaves behind 
 
 it a red, tatlelefs, and inodorous Roftrij that 
 affords no Smell even upon burning, nor diffolves 
 in any expreiTed or effencial Oil ; yet, even in 
 a fmall Proportion, tinges Spirit of Wine of a 
 full red Colour, fo as to render it ufeful for 
 anatomical Inje6lions, 
 
 Another 50. In like Manner may a particular gummy, 
 from Red red Subftance, or Figment, be obtained, by Spi- 
 IVtneLees.^'^^ of Wine, from dried red Wine Lees; and 
 whether the tinging Parts of the more cumber- 
 fome dying Vv^oods and Stuffs could not be ad- 
 vantageoufly extraded, at the Places of their 
 Growth, fo as to leave their ponderous Bulk 
 behind, and bring away only their concentra- 
 ted, elfential Colours, might deferve the Confi- 
 deration of the Merchant, the Dry-Salter, the 
 Dyer, the Callico-Printer, It might be 
 
 tried in Log-Wood, Campeche, or Brazil ; in 
 Madder, Safflore, and many other dying \¥oods 
 and Stuffs, whofe Names we feldom meet with 
 but in the Bills of Entry, 
 
 Experiment IV. 
 
 I'he Way of preparing an animal Colour called 
 Pruffian Blue. 
 
 ^iheProcefs 51. Take of Crude Tartar and Nitre, each 
 for making pulvcrizc, and mix them toge- 
 
 ther ; and, by Deflagration, bring them to a 
 fixed Salt ; which being powdered hot, add to 
 it four Ounces of thoroughly dried Ox-Blood, 
 reduced to fine Pov/der : Calcine the Mixture 
 in a covered Crucible, whereof it may fill tv/o 
 thirds : Then lightly grind the Matter in a 
 Mortar, and throw it hot into two Quarts of 
 
 boiling 
 
 O 
 
Of Colours. 309 
 
 boiling Water ; boil them together for half an 
 Hour ; afterwards (train off the Liquor, wafh 
 the black remaining Subitance with frefh Y/ater, 
 and drain as before; continuing to do thus till 
 the Water poured off becomes infipid. Put the 
 feveral Liquors together, and evaporate them 
 to two Quarts. Now diffolve an Ounce of 
 green Vitriol, firff calcined to Whitenefs, in fix 
 Ounces of Rain-Water, and hltre the Solution. 
 Diffoive alfo half a Pound of crude Allum in 
 two Quarts of boiling V/ater ; and add this to 
 the Solution of Vitriol, taktm hot from the 
 Fire; pouring to them likewife the firff Lixi- 
 vium, whilff thoroughly hot, in a large Veffel : 
 
 A great Ebullition and a green Colour will im- 
 mediately enfue. Y/hilff this Ebullition conti- 
 nues, pour the Mixture out of one Veffel into 
 another, and afterwards let it reff ; then (train 
 the Liquor thro’ a Linen Cloth, and let the 
 Matter, or Pigment, remain in the Strainer ; 
 from whence put it, with a wooden Spatula, 
 into a fmall new Pot ; pour upon it two or three 
 Ounces of Spirit of Salt *, and a beautiful blue 
 Colour will immediately appear. Let the Mat- 
 ter be now well ffirred; then fuffered to reft 
 for a Night ; afterwards thoroughly edulcorate 
 it by repeated Affufions of Rain-Water ; al- 
 lowing a proper Time for the Precipitate to fub- 
 fide ; And thus, at length, it will become ex- 
 quifitely blue. Laftly, let it drain upon a Linen 
 Strainer, and dry it gently : By all which Means 
 it becomes the Pigment that goes by the Name 
 of the Frujfian Blue, 
 
 52. The Succefs of the Experiment depends 7 '^'? 
 greatly upon the Calcination. The Crucible 
 is firff to be furrounded with Coals, at fome 
 Diftance ; that it may grow gradually hot, and 
 the Matter leifurely flame and glow, Let this 
 
 X 3 Degree • 
 
^lO Lecture the Fourteenth. 
 
 Degree of Heat be continued till the Flame 
 and Glowing decreafe , then raife the Fire 
 that the Matter may glow with an exceeding 
 white Heat, and but little Flame appear above 
 the Crucible. The Lixiviums fliould be very 
 hot, and mixed together with the utmofl Expe- 
 dition^. 
 
 ItsNature, 53- The Method of Pntffian Blue 
 
 in Ferfedion, has been held and purchafed as a 
 very valuable Secret, both in England^ Germany^ 
 and elfewhere ; but it is now got into feveral 
 Hands. Its Procefs is very extraordinary, and 
 could fcarce be deduced a 'priori^ from any rea- 
 foning about the Nature of Colours. It is allowed 
 an excellent blue Pigment, and by foine preferred 
 to Ultramarine \ tho’ its Durability might have 
 been fufpedled, from the vegetable and animal 
 Matters ufed in its Preparation, if the Colour 
 did not feem wonderfully fixed by the Opera- 
 tion. 
 
 'Manyani- 54. A great Variety of Colours are prepared 
 mauviat-^ by the Means of animal Matters-, and more 
 particularly by the Means of Urine ^ which, 
 when it has flood to ferment, or putrify, ferves 
 to extradl, change, or fix the natural Colours 
 of fome Bodies ; and to heighten the Colours of 
 Tarticu^ others. Thus it is ufed in the preparation of 
 the ordinary Blue called yfrrMj which chiefly 
 comes to us from Holland: It is alfo ufed in the 
 changing or fixing of Purnjol ; fo as to make a 
 mofl elegant Red from the Sun-Flower : It is 
 alfo a principal Ingredient, along with Indigo^ 
 in making that noble, fixed, and durable Blue, 
 very lately difeovered in England^ for the ftain- 
 ing of Callico^ a Colour thatfirft appears Green, 
 
 ^ See Fhilofophical Furnfa^iionsj N® 381, 
 
 but 
 
Of Colours. 
 
 31 
 
 but by wafliing with Soap changes, and fixes 
 into a lovely Blue. 
 
 55. Certain chemical Preparations from zm-The Spirit 
 mal Subjefts are likewife employed for extract- 
 
 ing, changing, or heightening the Colours ofva- 
 rious Bodies. Thus the alkaline, or volatile. 
 
 Spirit of Urine, Blood, Bones, extradls a 
 fine Blue from Copper, changes a green Solution 
 of Copper to a Purple, and heightens the Red 
 of Cochineal. And doubtlefs the prefent Stock 
 of Colours might be considerably enlarged, or 
 improved, by a prudent Choice of animal Men- 
 Jiruums. 
 
 56. By animal Menftruums we mean hoxh Am mal 
 the natural and artificial Kind : The natural are^'^^A"* 
 fuch as Blood, Serum, Gall, Urine, 
 
 Rennet, Whey, Butter-milk, ^c. mofc of which 
 being properly employed, will either difcharge 
 or produce Colours. Thus recent Urine dis- 
 charges the common Ink out of Linen ; the Sa- 
 liva difcharges Red Ink ; Butter-milk takes 
 Stains and Mildews out of Linen, Cfr. Blood, 
 we fee by our prefent Experiment, affords a 
 rich and beautiful Blue-, and Gall is a natural 
 Yellow -, which may deferve to be treated as 
 Blood, in making the Frujfian Blue. 
 
 57. Thefe natural animal Menftruums, orAn^iartif* 
 other animal Subftances, being chemically treat- 
 
 cd, may afford a great Variety both of fimple 
 and compound Liquors, or new artificial Men- 
 ftruums, for farther improving the Bufinefs of 
 Colours, Dyes, and Stains. Thus, as putrified 
 Urine affords an alkaline Spirit, by Djftillation, 
 that ferves to produce, alter, or deftroy a great 
 Number of Colours fd likewife might the Li- 
 quors obtained, by Diftillation, from recent, or 
 fermented Whey, Butter-milk, Cfr. And by 
 varioufly compounding thefe feveral Subftances, 
 
 X 4 or 
 
312 Lecture THE Fourteenth. 
 
 or Liquors, even by random Trials, or chance 
 Experiments, Tome new Difcoveries in ( clours 
 might be made *, as in the prefent Examf)le 
 of the Priiffian Blue: Tho’ we have a much 
 greater Dependence upon Experiments con- 
 dudled in a rational Manner ; or in the V/ay of 
 an Art, formed upon a competent Knowledge of 
 chemical Operations, with their Productions and 
 Effects j which will enable the Enquirer to rea- 
 fon, by Analogy, from one Experiment to an- 
 other ; and thus lead, in a fure and guarded 
 Manner, to new Inventions and Difcoveries. 
 
 ^he Expg- Thus, for Inftance, the chemical Opera- 
 
 7 end£d having found that common Bones, burnt only 
 to Blacknefs, alfcrd the Bone-black ; it is eafy 
 to transfer the Experiment to Ivory, v/hereby a 
 better Black is produced. And thus, upon find- 
 ing that dried Ox-Blood has fo great an Efiedb 
 in making the Fy^ujjian Bule^ we are naturally 
 led to try the fame Experiment with the Blood 
 of different animals *, or other concreted animal 
 . Juices, as Gall, Feathers, Flefh, Leather, 
 or the entire Bodies 'of certain Infefls, Fifh, 
 Birds, Gfr, And this fnould be done with pro- 
 per Diverfifications of the Ingredients, and their 
 Proportions *, all along carefully noting the feve- 
 ral Phenomena and Events •, which will conflant- 
 iy afford Light and inftrud'ion to the Mind, for 
 the better regulating and condudfing of the 
 Enquiry, till it ends in a full Difeovery. 
 
 Experiment V. 
 
 l^he Way of pt^eparing a metalline Colour^ from Gold 
 and ^in^for tinging Glafs of a beautiful Red, 
 
 ^ 59. Difiblve Gold in Aqua Regia ^ and dilute 
 t.he fine yellow Solution v/ith a large Proportion 
 
 of 
 
Of Colours. /313 
 
 l| of fair Water-, to the Mixture add, by Degrees, 
 a fufficient Quantity of a faturated Solution 
 1 ' Tin, made alfo in Aqua Regia ; and a mod 
 beautiful red, or purple coloured Powder will 
 i foon fall to the Bottom of the containing Glafs. 
 
 ' Decant the Liquor, and dry the Powder a 
 few Grains whereof being melted along with 
 , cryflalline Glafs, will tinge it throughout of 
 an extremely fine purple or 'ruby Colour ^2). 
 
 60. By Means of this Experiment the ancient 
 
 Art of Staining Glafs red, long fuppofed to ht itsUfes^h 
 loft, feems at prefent reftored. All the Colours of 
 are eafily given to Glafs, as we mentioned 
 above : But this feems to have been kept as a 
 Secret in very few Hands, till lately ; and may 
 be confiderably diverfified, fo as to introduce a 
 grateful Variety of beautiful red and purple 
 Colours in Glafs c). 
 
 61, It fhould alfo feem that the Art of Cal- Callico- 
 lico-Printing, which now wants a Red, equally Printing, 
 perfeft with the Blue it has lately obtained, 
 might hence be furnifhed with fuch a Red; tho* 
 
 there is Reafon to fufpecft it might come out too 
 dear for ordinary Ufe. But as the Perfedlion 
 of this Art confifis in difcovering fixed, bright, 
 and permanent Colours, not fubje<ft to change 
 for the worfe in the open Air -, fuch Colours 
 fhould rather be expedled from mineral or me- 
 tallic Matters, than from thofe of the ve- 
 getable and animal Kingdoms ; which ufually 
 afford Subjetfts of too lax and alterable a Tex- 
 ture for permanent Colours, unlefs they could 
 be fome way fubfi antially fixed. 
 
 a) Sec Cafius de Auro^ p. 105 . 
 
 See Exp. II. §. 15 . 
 
 c) See Mr. Philo fophical Works. Ahridgm, Vol. I. 
 
 P* 457—459- 
 
314 Lecture the Fourteenth. 
 
 Indian 62. It appears highly probable that the In- 
 Colours iians^ for making the fine, bright, and durable 
 ht^ma wherewith their Callicoes and Chintzes 
 
 are llained, ufe metalline Solutions ; for fome 
 flained Callicoes having been kept for forty or 
 fifty Years, the bright Colours have been ob- 
 ferved to eat out the Cloth, exactly in the fame 
 Manner as the corrofive, acid Spirits, which 
 diflblve Metals, are found to do : Whence, to 
 imitate their richeft and nobleft Colours, we are 
 direded to ufe proper metalline Solutions, made 
 after the Manner of our prefent Experiment. 
 ^heh'igheji 63. But it would be a farther Step towards 
 Improve Perfedion, not only in this Art, but alfo in the 
 Slrj Painting, to prepare the fineft Colours 
 
 without employing either acid or alkaline Salts ; 
 which ufually fubjed Colours to change, or elfe 
 are apt to prey upon the Cloth, or Canvas, as 
 v/e fee in Verdigreafe, the blue and green Cry- 
 ftals of Copper, Whence we are direded, 
 
 (i) to fearch for Menftruums that are neither 
 acid, alkaline, orfaline; (2) for fuch metalline 
 Cahes^ Precipitates, or Powders, as will not 
 lofe their Colours by being well waflied, to get 
 out their Salts; (3) to prepare certain metalline 
 Matters by Calcination, or the bare AlTiftance 
 of the Fire ; and (4) to look out for native Co- 
 lours, wherein no faline Matter abounds. 
 
 Variation 64. (i) It may be wortli the trying, whether 
 andExten Certain Metals are not foluble by Triture, with 
 fion of the pureft Oils employed in Painting, and fuch 
 
 Expert- contain neither acid nor alkaline Salts ; or 
 
 ^riturl whether mere Water, the Whites of Eggs, Sali- 
 va, Gum-Water, may not, by the fame 
 Means, be made todifiblve them ; fo as that the 
 metalline Particles may be left behind upon Cal- 
 licoes. Cloths, ^c. when the aqueous or mucila- 
 ginous Matter is dried, or walked away from 
 
 them, 
 
Of C clours. 315 
 
 them. But no great Effe6l can be rationally ex~ 
 peded in fuch Attempts, unlefs thcTriture be 
 long continued, and Mills, or other well adapt- 
 ed Engines, be ufed for the Purpofe : For we 
 find, in all Inftances, that Metals muft be redu- 
 ced to very fine Particles before they will tinge 
 or colour. 
 
 65. (2) The Pigments or Colours obtained 
 by Cryflallization, fuch as the blue and green 
 Vitriols, or Cryftals of Copper, cannot be 
 deprived of their aqueous or faline Parts by a//W. 
 dry Air, or by Walliing, without fuffering ex- 
 treme Alterations, or being left in the Form of a 
 grofs, terreftrial Matter, differently coloured 
 from what they were at firft. Thus the fine 
 green Cryftals of Iron, by being expofed to the 
 Air, become white; and when well wafhed in 
 Water, lofe their Greennefs, and turn to a 
 reddifh or yellow-coloured Ochre, or Earth ; 
 
 And if deprived of their faline and aqueous 
 Parts, by a ftrong Diftillation, they leave be- 
 hind a brown or red Caput mortuum ; which being 
 walhed in Water, affords not a green, but a 
 dark-coloured Pigment, or Kind of Spanijh 
 Brown. And as this holds proportionably of 
 other Colours obtained by Cryflallization, there 
 are little Hopes of procuring durable Pigments 
 
 by that Operation, which fhall be of the fame 
 Colours with the Cryftals themfelves; tho’, after 
 being well walhed, different Colours may be 
 thus procured. 
 
 66. (3) Metalline and mineral Matters zxtDryCahi.^ 
 reducible to a confiderable Degree of Subtilty 
 Smallnefs of Parts, by Fire, or dry Calcination ; 
 
 fo as to leave them durably poffeffed of their na- 
 tive or adventitious Colours. Thus Lapis La- 
 zuli., by being calcined, becomes the fine, du- 
 rable, rich Blue, called Ultramarine: Light Ochre 
 
'^i6 Lecture THE Fourteenth. 
 
 V/ 
 
 by the fame Treatment, becomes a light Red ; 
 or the moft ufeful Flefh-Colour in Painting, a) 
 Lead, by C alcination, becomes durably red ; 
 and Iron, durably brown. But a proper Me- 
 thod Teems wanting for the dry Caldriation of 
 the nobler Metals, Gold and Silver ; Though, 
 for the Ufes of Gilding, thefe nobler Me- 
 tals are eafily calcined by dipping linen Rags 
 into their refpedtive Solutions ; then drying the 
 Rags, and fetting them on Fire, fo as that they 
 may burn to Allies *, whereby a dry and fine 
 metalline Powder is readily obtained. 
 and 6j, (4) Many native mineral Pigments, or 
 durable durably tinging Subftances, are already difco- 
 
 abound with Salts ; fuch as 
 difccve- Ochre, both yellow and red. Cinnabar, or Ver- 
 raih. million, Zafibra, Manganefe, and doubtlefs 
 many others might be found in Countries that 
 are ftored with Mines, or where a proper Search 
 is made after new mineral Subllances h). 
 
 Ores tried Our prcfent Experiment likcwife affords 
 
 by the an ufeful Method of examining Ores, or difco* 
 gaining p/^veringa fmall Proportion of a metallic Subllance 
 in a large Proportion of Earth, i^c. for a Quan- 
 tity of pulverized cryltalline Glafs being ready 
 at Hand, it is but mixing a little of the Ore, or 
 mineral Matter, therewith, and melting them 
 together*, whereby the Glafs will be deeply or 
 lightly tinged of a certain Colour, according to 
 the Nature and Quantity of the Metal contained 
 in the mineral Matter. I'hus a little Silver tin- 
 ges white Glafs yellow, Copper green,Cf c. Putty, 
 or a Mixture of calcined Tin and Lead, turns 
 it Vv^hite, Cfr. tho’ thefe Colours will fomewhat 
 vary, according to the Mixture of the metalline 
 Matters with others, the Regulation of the Fire, 
 
 a) above II. §. 20. h) See ib. 
 
 and 
 
1 
 
 Of Colours. 317 
 
 and other Circumftances : So that a Sett of par- 
 ticular Experiments are required, to bring this 
 Affair to greater Certainty, and reduce the whole 
 to a regular T^ahle, But this Method, if fuffi- 
 ciently verified, might be commodioufly ufed, 
 when the Quantity of Ore, or mineral Matter, 
 is fmall, or contains but a very minute Propor- 
 tion of Metal *, for a little metalline Matter will 
 thus tinge a large Proportion of Glafs. 
 
 69. The Art of Enamelling in Glafs alfor;^^ 
 depends upon a prudent Ufe of mineral V\^-Enamd' 
 ments ; or a Mixture of Miniature- Painting and'^^* 
 Annealing ; For the Method here is, to lay 
 the Colours upon Glafs, as the Painter does 
 upon Canvas ; and afterwards to foften the 
 Glafs, by a proper Degree of Heat, in the An- 
 nealing-Furnace, under a Muffle, till the Co- 
 lours fink into the Glafs. And in this Manner 
 alfo is Glafs frequently coloured, on its more 
 fuperficial Parts, without being tinged through- 
 out ; as we fee in the coloured Glafs of certain 
 Church-Windows, and ancient Buildings. 
 
 
 AXIOMS and CANONS. 
 
 1. The preceding Enquiry fflews. That the 
 phyfical Caufe of the Generation, Variation, and 
 Deffrudlion of Colours in Bodies, is the diffe- 
 rent Refrangibility and Reflexibility of the dif- 
 ferent Orders of the Rays of Lights). 
 
 2. That Colours therefore are not inherent 
 m the Bodies faid to be coloured 5 but rather 
 in the Rays of Light which fall upon them ; and 
 are thence refle< 5 fed to the Eye, fo as to caufc 
 the Senfation of Colour b). 
 
 h) Ib, 
 
 a) Erp. I. ir. 
 
 g. That 
 
3i8 Lect ure t he Fo u rt e e n th. 
 
 3. That Colours, fo far as they may be con- 
 fidered as in the Bodies faid to be coloured, de- 
 pend upon a certain mechanical Texture, or 
 Mixture of the fmall farts of Bodies *, which 
 Texture, or Mixture, being altered, or deftroy- 
 ed, the Colours alfo are altered, or abolifhed a), 
 
 4. That Whitenefs in Light is an intimate 
 Mixture of the feveral Orders of Rays ; and 
 'W'hitenefs in Bodies, the adlual Refledion of 
 their Rays in their natural, mixed, or unfepa- 
 rated State b). 
 
 5. That Darknefs is the Abfence of the 
 Rays of Light *, and Blacknefs in Bodies, not 
 a Colour, but the V/ant of thofe Rays being re- 
 fledted from the Surface of the Bodies faid to be 
 black; or, in other Words, that Blacknefs is 
 produced by the Rays of Light being abforbed, 
 ftifled, or drank in, by the Bodies denominated 
 black c), 
 
 6 . That 1 'ranfparency in bodies is their Tranf- 
 mitting the Rays of Light ; and Opacity their 
 not Tranfmitting, but refiedling thefe rays 
 
 7. That common Light is compounded of 
 feven different original orders of Rays ; viz. 
 Red, Orange, Yellow, Green, Blue, Indigo, 
 and Violet ; and that according as Bodies refiedl 
 more or lefs of thefe Rays, fuch Bodies appear 
 of different fimpie or compound Colours e), 
 
 8. That great Alterations of Colours are pro- 
 ducible by a bare Alteration of the Arrange- 
 ment, Texture, or Mixture of the fmall Parts 
 of Bodies ; or by the Interpofition of different 
 Parts, upon bare Triture, and fimple Mixture/). 
 
 9. That vegetable and animal Colours are, in 
 general, lefs durable, or more fubjed to change, 
 
 c:) Exp, I. II. if) ib, f) ib. <t) ib. i) ib. f) Exp, 
 II. III. IV. V. 
 
 than 
 
Of Colours. 319 
 
 than the mineral Kind ; on Account of the loofer, 
 or more porous Nature and Texture of the two 
 former, and the ftronger and clofer of the lat- 
 ter a), 
 
 10. That the Arts of Enamelling, and Imi- 
 tating Precious Stones, in Glafs, depend upon 
 the Addition of metalline Cahes to the Glafs 
 of Lead, or pure cryftalline Glafs, in Fufion ; 
 and that an infinite Variety of the molt durable 
 and beautiful Colours are obtainable by this 
 Means h), 
 
 11. That many new Colours may be reafoa- 
 ably expected from a proper Enquiry into, and 
 a chemical Treatment of, various Subjedls of 
 the vegetable and animal Kingdoms c ) ; and that 
 there arc four principal Ways of obtaining new, 
 fixed, or durable mineral and metalline Colours ; 
 mz. (i) by difeovering new Menfiruums\ (2) by 
 finding fuch metalline Powders as will bear to 
 be waihed from their adhering Salts ; (3) by 
 properly applying dry Calcination; and (4) 
 by enquiring after native mineral Colours that 
 are not faline d). 
 
 12. That a great Variety of new and fixed 
 Colours may be prepared from Metals, and 
 their Menftruums, or certain Mixtures of metal- 
 line and mineral Matters, for the farther Ser- 
 vice and Improvement of the feveral Arts that 
 depend upon Colours, Dyes, and Stains e). 
 
 a) Exp. II. in. IV. V. Exp. It. V. 0 Exp. 
 III. IV. d) Exp. V. 0 Exp. II. III. IV. V. 
 
 LECTURE 
 
( 320 ) 
 
 7he Sub‘ 
 je^. 
 
 LECTURE XV. 
 
 CONTAINING 
 
 Attempts to illujlrate and improve the 
 common Ways of preparing Remedies, 
 
 I. HE Bufinefs we are now entering upon 
 ^ is Pharmacy ; a Subjed which has 
 almoft engrofled Chemiftry to itfelf : Whence 
 many underhand by Chemiftry little more than 
 the Preparation of Medicines. This Notion is 
 countenanced by the Books of Chemiftry gene- 
 rally publiftied ; which feldom contain more, 
 than Diredions for the Making of Medicines : 
 So likewife the Courfes of Chemiftry ufually 
 given, turn chiefly upon the Application of Che- 
 miftry to Pharmacy. 
 
 2. That Chemiftry is applicable to the Illu- 
 ftration and Improvement of many other Arts, 
 hath we hope been fhewn in the preceding Lec- 
 tures. But as the Application of it to Pharmacy 
 is a Thing of Importance to Life and Health ; 
 and as Men generally think that this is the prin- 
 cipal Offlce and Ufe of Chemiftry ; we judge it 
 proper to beftow two Ledures upon the Subjed : 
 in the firft whereof we propofe to confider the 
 prefent State of Pharmacy, with the Means to 
 improve it, upon the footing it now ftands ; and 
 in the fecond we will endeavour to ftiew how it 
 may be reduced to a greater Degree of Simpli- 
 city, and thus be brought nearer to Perfedion : 
 The one we may call the copious^ and the 
 other the condfe Method of Pharmacy. 
 
 3. We 
 
Of common Pharmacy. 321 
 
 3. We define Pharmaceutical Chemiftry., i\\tPharma‘ 
 Art of directing and performing the feveral^"^^^'^^ 
 Procefles or Ways of Working, whereby natu- 
 
 ral Subftances are reducible to ufeful Medicines. 
 
 4. And thus the whole Art confifts of two 
 Parts, a Pheory., and a Practice : The Theory is- 
 claimed by the Phyfician, and the Pradlice is 
 turned over to the Apothecary. 
 
 5. Mofl of the natural Bodies being ^omtHifloryof 
 Way or other employed as Subjeds of Pharmacy,^'^«A’w«9'. 
 the Materia medica is extremely large, and its 
 Operations various. Its Materials in the ear- 
 
 lieil Ages indeed were few, and the Ways 
 of managing them fimple : Subjedls after- 
 
 wards multiplied. Operations increafed, and at 
 prefcnt we feem abundantly flocked with both 
 fimple and compound Medicines. 
 
 6. But the Hiflory of Pharmacy may deferve 
 to be more particularly traced, in order to fee 
 by what Means it arrived at its prefent State, 
 and how it may be farther advanced. 
 
 y.Difeafes mufl have begun very early, if the firft 
 Inhabitants of the World experienced the fame 
 Changes of Seafons, breathed the fame Kind of 
 Air, and ufed a like Diet and Regimen of Life 
 with ourfelves. But foon after a Difeafe afflidls, 
 the Patient feeks for a Remedy : Whence we 
 may reafonably fuppofe that this was the Foun- 
 dation of Pharmacy in various Parts of the 
 World. 
 
 8. Experiments being thus multiplied^ and 
 the Event gradually introducing better Methods 
 of preparing the Simples, Fharm.acy would be- 
 gin to appear in the form of an Art : Yet when 
 Hippocrates came to compile a Kind of Syftem of 
 Phyfic from the Obfervations of Antiquity, he 
 defcribed but fev/ Preparations, and'thofe were 
 generally fimple. 
 
 9. Suc- 
 
 Y 
 
322 Lecture the Fifteenth. 
 
 9. Succeeding Phyficians enlarged the Materia 
 medica : Galen confiderably fwelled the Cata- 
 logue, which received many Additions from the 
 Arabians, 
 
 10. And when Learning began to revive in 
 Europe^ the Materia medica was again enlarged, 
 and great Changes wrought upon it by Chemf- 
 ftry : Whence Chemiftry at length was general- 
 ly received, and acknowledged to be of ufe in 
 Pharmacy. 
 
 11. Both the Galenic and Chemical Part of 
 this Art are now extremely copious. NecefTuy 
 gave the Occafion ; Nature fupplied the Mate- 
 rials-, and Art and Obfervation difcovered their 
 Preparations, Virtues, and Ufes. 
 
 12. Thus we at prefent feem provided with a 
 Competency of (landing Medicines and have, 
 by Degrees, acquired a Method of prefcribing 
 in extemporaneous Forms, 
 
 13. The Art of Pharmacy may be confidered 
 as under the Management of Phyficians, Apothe- 
 caries, trading Chemifts, and Druggifts. 
 
 14. It is the Office of the Phyfician to direfl 
 the Medicines, or give Rules for extradling, 
 compounding, and managing the Simples. If 
 the Phyfician therefore fhouid be defedive in 
 this Part, let the Apothecary, the trading Che- 
 mift, and the Druggift, be ever fojuil, or ever 
 fo knowing, the Art of Pharmacy mud fall (hort 
 of Perfection. 
 
 1 5. To the Apothecary belongs the Reduction 
 of the Materia medica into certain Forms of Me- 
 dicines, according to the Direction of the Phy- 
 fician. 
 
 16. But there are two Kinds of Apothecaries, 
 vulgarly known by the Names of wholefale and 
 retail Apothecaries. It is the latter alone we 
 are here concerned with : Thefe aCt by Rule, 
 
 gene- 
 
Of comfnon Pharmacy. 323 
 
 generally follow their Standard, and compound 
 with Art and Care *, tho’ they will fometimes 
 fubftitute a quid pro quo.^ and now and then ven- 
 ture to reverfe an Order. In Proportion to their 
 Skill and Care they are more or lefs liable to be 
 impofed on by the Druggift and the trading 
 Chemill ; all of them ulually felling what they 
 buy. But if the Apothecary be often deceived 
 by them, how Hands it with the Patient and Phy- 
 V fician ? or what is the State of Pharmacy ? 
 
 17. The retail Apothecaries, however, deal 
 more in Subjlitution than in Sophiftication. The 
 prudent Phy fician therefore prefcribes what is 
 ufually kept, and proper to keep, in the Shops, 
 or what is otherwife eafily obtainable. If there 
 are other Abufes committed in this Part of Phar- 
 macy, they may perhaps be chiefly attributed 
 to fome Want of Skill or Conduct in the Phy fi- 
 cian. 
 
 18. The Defign of the trading Chemifts and 
 Druggifts is to furnilh medicinal Matters to the 
 Apothecary, who cannot always detedf an art- 
 ful Counterfeit, or a dexterous Sophiftication : 
 
 And perhaps many Remedies, well defigned by 
 the Phyfician, have failed, or had mifchievous 
 Effects, upon this Account. 
 
 19. This is propofed as a fliort Intimation 
 of the prefent State of Pharmacy in England, if 
 the Art be found more perfedt in other Nations, 
 it may perhaps be chiefly owing to this. That 
 their Phyficians are well acquainted not only with 
 the Theory, but alfo with the Fradlice thereof; 
 two Things which fhould never be feparated, as 
 being in Reality butoneeftedtive Thing confifting 
 of two Parts ; viz, previous Notion, and Ex- 
 ecution. 
 
 20. What ufeful Addition or Reformation the 
 Materia rnedica is capable of receiving, no one 
 
 y 2 at 
 
324 Lecture the Fifteenth. 
 
 at prefent can fay. If a ftridt Enquiry were 
 made, perhaps it might be found proper to 
 throw out of our prefent Colledion a confide- 
 rable Number of Materials, to make Room‘for 
 others of greater Efficacy. But this is no Work 
 for private Perfons. Our prefent Bufinefs is to 
 fee whether any Improvements may be made in 
 the Ways of preparing the common Medicines of 
 the Shops. 
 
 Deftgn of 21. And for the better regulating of our En- 
 
 Fharmacy. it may be of fome Service to lay down 
 
 two larger Obfervations •, viz. (i) That the 
 Defign of Pharmacy is to feparate from Bodies 
 the more medicinal Parts with which they are 
 naturally endowed *, and, upon Occafion, to mix 
 fuch of them together as will bell anfwer the 
 curative Intentions. All in the Power of Art 
 is only to feparate and mix, or differently modi- 
 fy j it is Nature alone that is able to produce. 
 Pharmacy therefore confifts in Analyfis and Syn- 
 th efis 
 
 22. (2) As it is the Perfection of Art to co- 
 py Nature jullly, fo by refolving Bodies into 
 their Principles we obtain a general Rule for 
 Compofition, and fee the feveral Steps we ought 
 to take in it. Nature fhews us that in all 
 mixed Bodies there is a Bafis or Subjlratum-y 
 fomething to fiipport and envelope the other In- 
 gredients. Thus natural Salts are the diluted 
 with Water ; the Oils with both ; and all toge- 
 ther compofe one uniform and elegant Whole. 
 To preferibe jullly, therefore, we Ihould imi- 
 tate Nature : If we compound without Re- 
 gard to this Rule, the Ingredients will appear 
 huddled together, as if it were by Chance j and. 
 
 ^ See Lea. VIII. and IX. 
 
 inllead 
 
Of common Pharmacy. 325 
 
 inftead of preferving and affifting, they will often 
 clog, encumber, and deftroy each other. 
 
 23. We now proceed to our Experiments, 
 by which we propofe to illuftrate and improve 
 (i) the common Method of diftilling Simple- 
 Waters *, (2) the common Method of preparing 
 Tin6tures ; (3) the Method of preparing Sy- 
 rups (4) the Method of making Eleduaries ; 
 and (5) the Method of making compound Oils, 
 Unguents, and Plaifters : Thus propofing to 
 touch upon the chief Articles ot the prefent 
 Galenical Pharmacy^ as it is vulgarly called *, tho’ 
 in Reality it be no lefs chemical than the other. 
 
 Experiment I. 
 
 The heft IVay of diftilling Simple-Waters, 
 
 24. We took as much dried Mint, cut fmall, 5 //^//? 
 as filled two thirds of our Still; then adding ^.^aters,^ 
 Quantity of Rain-Water fufficient to make the^JJ^ 
 Plant float commodioufly, yet leaving a fourth 
 
 of the Still empty, we digefled a while with a 
 gentle Heat; then worked the Still, drawing 
 off only fo long as the Water appeared thick 
 or milky, and tafted rich and grateful ; where- 
 by we obtained a Simple Mint-Water in tolerable 
 Ferfedion. • 
 
 25. This Experiment, with a few occafional 
 Aiterations, may ihew a general Method of ob- 
 taihing Simple Waters in their greatefl; Perfec- 
 tion. The Subjeds befl: fitted for it are thofe 
 of the odorous, aromatic, and oily Kind ; tho’ 
 fome others alfo may perhaps communicate par- 
 ticular Virtues to the Water: Among the fittefl: 
 may, however, be reckoned, Angelica^ Annifeed,, 
 Baulm^ Calamint^ Cmnamon^ Cloves, Fennel^ Hy- 
 fop, Rofemary^ Tanfey^ JVortnwood^ &c. but parti- 
 
 y 3 cularly 
 
■; 
 
 326 Lecture the Fifteenth. 
 
 cularly Pepper-Mint, which affords anextremC'- 
 ly aromatic, pungent, and agreeable Water, 
 good againft the Cholic, and many other Difor-^ 
 ders ot the Stomach and Bowels ; though its 
 Ufe is, perhaps, too little known. 
 
 CautioKs. 26. it is a principal Caution, in this Opera- 
 tion, to remove the Receiver before the more 
 pellucid, acid, faint, and dead Water comes 
 over, as it foon will do ; and if fuffered to mix 
 among the reff it is apt to fpoil the whole, by 
 giving it a vappid or faint Tafte, and fometimes 
 a Degree of Acidity, or vitriolic Stypticity, and an 
 emetic Quality ; for Part oftheeffential Salt of the 
 Plant, which now begins to rife, ufually corrodes 
 the Copper Head of the Still, and carries over 
 with it fome Particles of the Metal. Hence thefe 
 Waters fliould be diftilled either with a Glafs 
 Head, or one of Pewter, or wtII tinned Copper ; 
 or elfe the Operation fhould be carefully watched, 
 that the fecondj Running may not mix with 
 the hrft. The greater Care fhould be taken, 
 becaufe fome Patients, more particularly Chil- 
 dren and thofe of a tender Habit, have fuffered 
 thro’ a Negled herein ; and been vomited, pur- 
 ged, and griped by the Ufe of a Simple Water, 
 contrary to the Intention. 
 
 ^egula- 27. The Simple Waters diftilled after the 
 nun. Manner of our prefent Experiment may in ma- 
 ny Cafes prove too ftrong to be ufed alone , but 
 then it is eafy to let them down to the proper 
 Strength with common diftilled Water : And 
 this is, beyond all Comparifon, better than to 
 mix fuch Waters with their own Faints, or Li- 
 quor of the fecond Running. 
 
 JmiA-o<ve^ 28. Two Improvements might be made in 
 PiLn. this Method of obtaining Simple Waters : 
 The firft, by means of Coliobation and 
 Digeftion; the other, by means of a pre- 
 vious 
 
I Of common Pharmacy. 327 
 
 ! vious Fermentation of the Plant. With regard 
 I to the firft; If the Liquor remaining in the Still 
 be exprelTed from the Herb, and returned, along 
 with all the Water that came over, upon a 
 ; frefh Quantity of the fame Subject, and they be 
 I digefted together in a gentle Heat for two Days, 
 
 ! and then diftilled as before, the Water thus 
 obtained will be much richer and more effica- 
 cious than the former : And if the fame Pro- 
 1 cefs be repeated two or three Times, thofe who 
 ! have not tried would fcarce imagine how rich 
 ' a Simple Water may be thus procured. This 
 I Method we would particularly recommend 
 [j . for making the Simple Water of Baulm, Elder- 
 i: Flowers, Roles, Camomile, and fuch Subjeds 
 
 J as are but fparingly furnilhed with ellential 
 Oils ; for otherwife they make but indifferent 
 I Waters. 
 
 i 29. The other Means of improving Simple 
 I Waters is by ufing a previous, imperted Fer- 
 mentation : This is performed by adding to the 
 Plant and Water, put together as in our pre- 
 fent Experiment, a tenth or twelfth Part of 
 Sugar or Honey, or elfe a fortieth Part of 
 Yeaft ; then fetting the whole in a warm Place 
 to ferment for two or three Days only, fo that 
 the Herb may not fall to the Bottom, nor the 
 Fermentation be above half hniffied : thewholc 
 being afterwards committed to the Still, a Water 
 may, at one Operation, be obtained extremely 
 rich, or impregnated with the full Virtue of the 
 Plant. And thus may Simple Waters be made 
 fit for long keeping without fpoiling; the fmall 
 Proportion of inflammable Spirit generated in 
 the Fermentation ferving excellently topreferve 
 them. And thefe two Methods feem applicable 
 to the Improvement of all thofe Simple Waters 
 commonly found in the Shops. 
 
 Y 4 
 
 30. We 
 
328 
 
 Lecture'the Fifteenth, 
 
 30. We fhould nej^t proceed to fhew the 
 Method 'of perfe< 5 ting or improving Compound 
 Waters, it we had not already endeavoured to 
 do it in our Lecture upon Diltiliacion by an 
 Example in Citrcn-V/ater 
 
 Exp e r I m e n t II. ‘ 
 
 ne heft IVay of making light "Tin^ures^ and In- 
 fuJiGns. 
 
 LightTinc- 31. We took half an Ounce of the Rind of 
 turei pre- Sevilk Orange iliaved thin, halt a Dram of 
 pared. Gentian Root thin diced, a Scruple of the 
 Tops of Roman Wormwood, half a Dram of 
 Cardamums, and halt a Dram of Cochineal, 
 each of them lightly bruifed : Thefe Ingredients 
 we put to deep for a night in a Pint French 
 Brandy, and filtred the Liquor the next morn- 
 ing. 
 
 Kegula- 3 ^* Experiment is general, and not per- 
 iion. formed for its own Sake, but to lliew the Method 
 of miaking ail Kinds of the lighter and finer Tinc- 
 tures and Infufions without Fire, which would 
 here prove prejudicial. The Preparation itfeif 
 is, however, a good Stomachic Bitter, of the 
 fame general Nature with thofe commonly fold 
 under the name of Stoughton's Elixir. The Ex- 
 cellence of thefe Preparations depends not niorc 
 upon the Choice and Goodnefs or the Ingredients, 
 than upon the Manner of their being infufed : 
 For if fuftered to remain too long in the Men- 
 ftruum, or if Fieat be ufed in extradling the 
 Tiridure, the grofs, terreftrial, and naufeous 
 Parts of the Ingredients will be fetched out, 
 and the Tincdure thus be loaded with a heavy 
 
 * See un. xm. Exp. V. 
 
 inert 
 
’ Of common Pharmacy. 
 
 inert Matter, of little Virtue. But if the 
 Infufion be made in the Cold, and the Liquor 
 ftrained off Ibon, only the finer and more fpiri- 
 tuous Parts of the Ingredients will be imbibed 
 by theMenftruum j whence the Preparation will 
 not only tafte and fmell more brisk and agree- 
 able, but alfo have a much greater Virtue and 
 Efficacy. But if, thro’ the Shortnefs of their 
 Continuance in Infufion, the Ingredients ffiould 
 not have fufficiently impregnated the Liquor, 
 the bell Method is to pour it again upon 
 freffi Ingredients, and again to ftrain it off, 
 without letting it flay too long upon them, or 
 api lying the Heat of the Fire. And thus, by re- 
 peated Affufions of the fame impregnated Men- 
 flruum upon freffi Ingredients, an Infufion or 
 Tindture may be obtained, of almoft any De- 
 -gree of Strength orRichnefs, without containing 
 the groffer or more inablive Parts of the In- 
 gredients, but only what may be called their 
 finer Spirit or Quinteffence. And this is no 
 inconfiderable Secret both in Chemiftry and 
 Pharmacy, and may deferve Regard of rhofe 
 who defire to procure the full Virtues of the 
 Simples, unaltered in their Nature, yet exalted 
 or concentrated to fuch a Degree, that a few 
 Spoonfuls of the Liquor ffiall contain the Spirit 
 or Qiiinteffence of a Pound of a Plant. And 
 this is an Effedt not to be expedled from the Fire, 
 which almoft conftantly alters the Nature of 
 Things committed to it j nor can a valuable 
 Effence of Violets, Jufmin, Lilies, Borage-Flow- 
 ers, or any f lower or Plant of an extremely 
 fine odoriferous Spirit, be procured by Pleat, 
 tho’ it readily may by fteeping thefe Flowers in 
 cold Water, cold Vinegar, cold Wine, or the 
 like, and frequently pouring the Tindlure upon 
 
 freffi 
 
330 
 
 Lecture the Fifteenth. 
 
 frefli Flowers, till the Liquor becomes ftrongly 
 impregnated. 
 
 33. Apothecaries ufually commit the fame 
 Error in preparing the finer Tinctures, that they 
 do in making their Cordial Waters *, in both 
 Cafes fatu rating the Liquor with the grofler, 
 more ufelefs, and lefs fpirituous Parts of the 
 Ingredients ; whence the Cordial Waters of the 
 Shops too often abound with a grofs, heavy, dif- 
 agreeable Oil •, and the Tindures of the Shops 
 with a grofs, heavy Earth, or Kind of bitumi- 
 nous Matter, inftead of a brisk, lively, and in- 
 vigorating Spirit ; v/hich alone is the Thing re- 
 quired in both Cafes. 
 
 34. This DoCfrine of Tin 61 ures and Infufions 
 
 iliould be reduced to Rule for the Improvement 
 of Chemifiry, which will never be perfected till 
 it can extra6f, feparate, and concentrate, the 
 Virtues of Things unimpaired, or unaltered in 
 their Nature. And doubtlefs it would prove a 
 very ferviceable Thing in Chemiftry, Medicine, 
 and Natural Philofophy, to know the befi: and 
 cafieftWay s of concentrating the Virtues of Bod ies 
 unaltered: And this may, in fome Meafure, 
 
 be effected by our prefent Method, and the 
 Ufe of well a dapted Menftruums : For, in 
 general, (i) a quick and cold Infufion extracts 
 the Spirit of Vegetables but a long and hoc 
 one confounds, impairs, or deftroys it. (2) To 
 repeat quickly thecold Infufion of a frefh Subject 
 in the fame impregnated Menfiruum, feems 
 greatly to collect and concentrate the Spirit, 
 that is, the finer and more effential Part of 
 Bodies. (3J The proper Menftruums for this 
 Purpofe feem to be fuch as pure Rain-Water, 
 Vinegar, Wine, Water mixed with a little fine 
 Alcohol, Water and a little Sugar ; and for 
 certain Ufes, the common atmofpherical Air, 
 
 which 
 
, Of common Pharmacy. 331 
 
 ! which^an excellent Menftruum to extradl the 
 jSpiritf or Effluvia of Plants, as we remarkably 
 jfi-nd in fpicy Groves Gardens, and may be 
 I ufed with good Effe( 51 :. 
 
 : 35. But to obtain the faturated Tinflures of 
 
 ihard, refinous, or gummy Bodies, requires a 
 [ different Treatment, as in the following Ex- 
 ii periment. 
 
 36. We took two Ounces of that hard IndianSoIution , «/ 
 1 Rofin called Gum Lac.^ and reducing it into a^^^^ 
 fine Powder, made it into a Kind of ffiff Pafte 
 i with Oil of Tartar fer deliquhim\ wc fet this 
 I Pafte in an open Glafs to dry by a gentle 
 ! Heat; then removed it to the open Air, that 
 it might relent or grow foft*, and after this 
 we dried it again as before : By repeating 
 the Procefs once or twice the hard Body of the 
 Rofin was at length refolved into a purple co- 
 loured Idquor ; which being now gently dried, 
 and reduced to Powder, afforded an excellent 
 Tinsfture, by being boiled for two or three Hours 
 in a tall Glafs with Alcohol. 
 
 57. This Procefs is almoft general, or mayr/^^ Ex^e- 
 be advantageoufly ufed for making theTin6tures''^'^^«^ 
 of Myrrh., Gum Juniper., Dragons-Blood., Amber 
 and other hard, gummy Subftances, which will 
 fcarcc otherwife yield a Tinfture in Spirit of 
 Wine. Any Improvement in the extra( 5 ling 
 Tindtures with Alcohol may tend confiderably 
 to improve the Art of Pharmacy, becaufe fuch 
 Tindlures are generally found powerful Medi- 
 cines, the Spirit of Wine appearing greatly to 
 increafe the Virtue of the Subjedls. Thus, tho’ 
 the Tindture of Amber prepared in this Manner 
 appears to be only a bare Solution of the Sub- 
 ftance of the Amber, yet it is found to have 
 fuch Effedls as are no Way equalled by any fine 
 Powder of Amber : And what feems remark- 
 able, 
 
332 Lecture the Fifteenth. 
 
 able, tho’ fo large a Quantity of fixed Alkali be 
 ufed in the Preparation of thefe Tindlures, yet 
 they give no manifeft Signs of containing an 
 Alkali ; which is therefore changed in the Ope- 
 ration, either by the Acid naturally contain- 
 ed in thefe refinous and gummy Bodies, or by 
 being expofed to the Air, or by both. 
 
 Varied 3 ^* There are other Methods of extra6ting 
 the Tindures of thefe hard, gummy Bodies, 
 but that delivered appears to be the bell ; tho’ 
 it might perhaps be fhortened, by ufing fome 
 proper intermediate Subftance to divide the 
 Particles of the Subjedl, fo as that the alkaline 
 Salt, the Axir, 'and the fpirituous Menftruum 
 might all come into fuller contadl therewith 
 and a6l more forcibly thereon. And for this 
 Purpofe we would recommend pure virgin Earth, 
 fuch as is commonly ufed for the making of 
 Tefts or Cupels ; by Means whereof Spirit of 
 Wine will extract a tolerable Tindure from 
 Myrrh^ without the Addition of any fixed Ad- 
 kali. 
 
 39. But when TincTures not fpirituous, or 
 
 only aqueous Solutions oF thefe hard, gummy 
 Bodies are required, we recommend the Ufe of 
 the foluble Tartar, art arum T'artarizatum \ 
 
 for a Solution of this Salt will readily difiblve 
 Myrrh, even in the Cold j as Water diifolves 
 Gum-Arabic 
 
 ExPE R I ME NT III. 
 
 "The hefi Method of making Syrups, 
 
 40. We took three Ounces of the yellow ex- 
 ternal Rind of frefii Oranges, and infufed them 
 in a clofeVefiel, with a gentle Heat in Balneo 
 
 ^ Sec Lea XIII. Exj>, V. §.47. 
 
 
Of common Pharmacy. 333 
 
 Mart<e^ for fix Hours, along with a Pint and z.^yrup of 
 half of pure Water *, then fuffering the Infufion^''^^^^^ 
 to cool we filtred the Liquor and, adding 
 it twice its own W^eight of hard double-refined 
 Sugar, made it into a Syrup, in a clofe Veflel 
 fet in Balneo Marine. 
 
 41 . We could not contrive a general Example Ufes, 
 to fit all Syrups, becaufe they differ greatly in 
 Refpedl of the Liquors of which they are made^ or 
 according as thefe Liquors are Infufions,Decoc- 
 tions, natural Juices, Wines, or Vinegars. We 
 chofe to give an Inftance in a Syrup made of a 
 Liquor by the Infufion of an aromatic Subftance, 
 whofe Virtue would be almoft intirely loft it 
 the Syrup were to be prepared by long Boiling, 
 
 as it is fometimes directed, with lefs than an 
 equal Weight of Sugar. Difpenfatory- Writers 
 have perhaps no where erred more remarkably 
 than in directing the Making of Syrups ; y/hich 
 feem.s the more ftrange, becaufe this Part of 
 Pharmacy is extremely facile. The Misfortune 
 feems to have lain here, that great Men cannot 
 fubmit to confidcr common and ordinary Things; 
 neverthelefs the Credit of a Phyfician may fink 
 in the Efteem of thofe who by their Employ- 
 ment are led to a Knowledge of thefe ordinary 
 Things. 
 
 42. We judge that the Whole of this Bufinefs 
 may be reduced to a few eafy Rules, which we 
 fhall here endeavour to lay down for improving 
 this' Branch of Pharmacy. And ( i ) It is Mat- Rules. 
 ter of Experience that aqueous Infufions, De- 
 codfions, or other aqueous Liquors, require 
 twice their own Weight of dry Sugar -Candy 
 
 to make them into a Syrup of a juft Confiftence 
 for keeping, without candying or fermenting. 
 
 This Rule, by diredfing the Ufe of Sugar -Candy 
 feems to fix the Confiftence of Syrups with Exadl- 
 
 ,nefs \ 
 
334 Lecture the Fifteenth. 
 
 nefs; becaufe all Salts acquire a determinate 
 Proportion of Water in cryftailizing ; fo that 
 Sugar in the Form of Candy confilfs of one cer- 
 tain Proportion of Water, whilfl different Kinds 
 may hold more or lefs aqueous Matter, accord- 
 ing to the Manner of' refining, the Accidents 
 of Weather, (ffc. Hence therefore all fuch 
 Intufions for Syrups as are of a delicate or de- 
 ftrudlible Colour, which is impaired by boiling 
 (for Example, Violets, CloveJuly-Flowers,Cf^*. j 
 and all fuch Infufions as contain any volatile 
 Parts, which would evaporate by a boiling Heat, 
 (for Example, thofe of Nutmeg, Cinnamon, 
 Orange-Peel, Citron-Peel, ^c.) fhould have 
 twice their own Weight of Sugar added to them, 
 and be kept clofe covered in the gentle Heat of 
 a Balneum Mari a ^ till the Sugar is diffolved ; 
 to haften which the Sugar fliould befirfi: reduced 
 to fine Powder. 
 
 43. (2) The Decodlions of fuch vegetable 
 Subfiances as lofe no valuable Parts by boiling, 
 may be boiled down to the Form of a Syrup 
 along with their own Weight of Sugar *, the two 
 being firfi clarified together with Whites of 
 Eggs in the ordinary Way : But if the Ingre- 
 dients here contain any undluous or balfamic 
 Parts on which their medicinal Virtues depend, 
 let the Sugar be added from the firfi, and boil- 
 ed along with the Ingredients •, afterwards 
 firaining and clarifying the Decodlion, before it 
 is boiled to near the full Confifience of a Syrup. 
 This Rule is founded upon that remarkable Pro- 
 perty which Sugar has to diflblve Oils, or the 
 finer refinous Subfiances, fo as to make them 
 intimately mix with Water. Whence it may 
 deferve to be confidered whether the Syrup of 
 Myrtles^ Comfrey^ and Diacodium fhould not be 
 thus prepared. It mufi aifo be obferved that 
 
Of common Pharmacy. 335 
 
 by boiling the Sugar fo long with the Deco6Hon 
 the aqueous Part exhales, and leaves the Syrup 
 much ftronger than it could have been made 
 without this boiling. 
 
 44.(3) vegetable Juices are to be tho-* 
 roughly purified before they are made 'into Sy- 
 rups. Thus the Juices of Citrons, Lemons, 
 and Oranges are to pafs the Filtre, and then 
 be made into Syrups, without boiling, according 
 to the firft Rule^ obferving to ufe no metalline 
 Veflel about them. But the Juices of Fruits, as 
 particularly Mulberries, Rasberries, will 
 not clarify without a beginning Fermentation \ 
 but by (landing for a Day or two they will be- 
 gin to ferment and liquify, and may then be 
 commodioufly drained thro’ Flannel •, after which 
 thefe alfo are to be made into Syrups with about 
 an eighth Part lefs than twice their own Quantity 
 of Sugar, or with two Pounds and twelve Oun- 
 ces of Sugar to a Pint of Juice, on account of 
 their being fomewhat faccharine themfelves. 
 
 And this holds alfo of Wines and Vinegars, 
 when they come to be made into Syrups ; for 
 Wine contains an inflammable Spirit which 
 does not incorporate with Sugar ^ and alfo a 
 thick fyrupy Subftance, which is found in 
 Vinegar likewife. By a due Application of thefe 
 Rules we apprehend the Bufinefs of making 
 Syrups may be brought to tolerable Ferfedtion. 
 
 Experiment IV. 
 
 The hejl Method of making Ele^uaries^ by an Ax- 
 ample in the Sajfafr as -Electuary. 
 
 45. We took two Ounces of the bed Saffafras Safa- 
 newly rafped, and half an Ounce of CinnamonA^^ 
 finely powdered j thefe Ingredients w^e boiled 
 
 a tall 
 
Regular 
 
 tion. 
 
 Rules, 
 
 Lecture the Fifteenth. 
 
 a tall Glafs in a Sand-Heat, with ten Ounces 
 of Warer and fourteen Ounces of Sugar, fo as 
 that nothing might evaporate, tor two Hours ; 
 then ftraining and prctfing out the Syrup, we 
 added to it an Ounce of frefh rafped Saflafras, 
 a Dram of Cinnamon, and ten Gnnns of Nut- 
 meg, both reduced to fine Powder ; and made 
 the Whole into an Eleduary. 
 
 46. In the common Method of making this 
 Eleduary the Saffafras and Cinnamon are boil- 
 ed in the Water, whereby a great Fart of their 
 Virtue is loft or not extraded : Whence the 
 Medicine comes to be defrauded of its Due. 
 But here, by boiling the Ingredients in a tail 
 Glafs, with a due Proportion of Sugar and 
 Water, to make a Syrup (allowing an extraor- 
 dinary Proportion of Water for what the Saf- 
 fafras will drink up) we obtain the fine aromatic 
 Virtues of the Ingredients to Advantage, with- 
 out any confiderable Lofs. 
 
 47. To make Eleduaries in Ferfedion where' 
 a Syrup is employed as their Bafis, (i) the Sy- 
 rup fitould be prepared in the Manner above 
 delivered fo as that the Virtues of the In- 
 gredients may be preferved •, (2) the Pow^ders, 
 or Species employed, fliould be frefh and fine 
 ground ; (3) the Gums, where any are ufed, 
 muft be wxll cleanfed, and diftbived in their 
 proper Menftruums ; and (4) the WTole muft 
 be mixed, or thoroughly united, into a finooth, 
 uniform Subftance, of a due Confiftence for 
 keeping, without either candying or running 
 into Fermentation. 
 
 48. (1) Where Syrups are ufed in the mak- 
 ing of Eleduaries, care is not only required that 
 the Virtues of the Ingredients of the Syrups be 
 
 * Exf. in. 
 
 pre- 
 
Of common Pharmacy. 
 
 prefervcd as much as the Form will allow of, 
 but alfo that its Confiftence be not too high \ 
 for this would difpofe it to candy in the Elec^tu- 
 ary, and render the Medicine unduly mixed, 
 or knotty; the Sugar concreting together in 
 Lumps, or fhooting away from the Species. 
 Again ; If the Syrup be made too thin or aque- 
 ous, fo as not to fufpend and hold the Powders 
 together by a binding Confiitence, it will 
 of Neceflity ferment in hoc Weather, and be- 
 come firft fomewhat vinous, afterwards four or 
 acetous, and at length corruptive d ) ; fo as to 
 change, invert, or deftroy the Nature of the 
 Medicine : For purgative Ingredients, by Fer- 
 menting, lofc their purgative Virtues ; and all 
 other Ingredients, by Corrupting, are reduced 
 to an inert Kind of Fsces or Caput mortuum.^ 
 very different from the Thing intended b). And 
 hence Electuaries that have thus fermented, or 
 changed their Nature, may fometimes prove per- 
 nicious, inflead of falutary. 
 
 49. The Electuaries made with the Pulp of 
 Fruits are lefs difpofed to keep, for any confi- 
 derable Time, perfeCt, on account of the greater 
 Tendency which fuch pulpy Subftances have to 
 Fermentation and Putrefaction. Thus, tho’ the 
 Lenitive Elebtuary were made ever fo artificially, 
 it will fcarce keep many Months without altering 
 its Nature; but efpecially if the Confiftence was 
 originally too thin : Whence fuch EleCtuaries 
 fhould be made in fmall Quantities, or frefh as 
 they come to be wanted. 
 
 50. But this does not equally hold of the ca- 
 pital Ele5fuaries.i fuch as Venice-Lrcacle., or Md 
 thridate \ which require to lie forfome Time, that 
 the Ingredients may digeft, or ripen, as it were, 
 
 a) See X. paffm. b') See VII. 
 
 Z and 
 
 337 
 
Lecture the F ifteenth. 
 
 and grow mellow together j for the Gums and 
 Spices that enter thefe Compofitions prefervethe 
 Medicines from Alterations for the worfe, and 
 the Mixture becomes more perfedl by Time ; 
 provided the Honey ufed in their Compofition 
 do not candy, or the Whole become too dry. 
 To keep the Honey from candying,fome Artifts 
 mix the Spices and Gums with it unclarified ; 
 only taking Care to feparate the foul Parts that 
 lodge either at the Top or Bottom. And if the 
 Medicines prove too dry, it is ufual at any Time 
 to foften, or beat them up in a Mortar, with 
 Canary : And thus thefe Capitals of the Shops 
 are fuppofed to improve by keeping. But Biaf- 
 cordium^ having few of the warm Gums in its 
 Compofition, is more apt to alter, and lofe of 
 its aftringent or ftyptic C^ality by keeping : For 
 which Reafon it feems an Alteration here for the 
 better, to ufe a Quantity of Saccharumrofatum in* 
 ftead of Honey, oxDiafcordium \ as this not only 
 gives a greater Compadlnefs to the Medicine, 
 but alfo contributes to preferve its Colour and 
 Virtues. 
 
 51. (2) The Powders, or Species, that enter 
 the Compofition of Eleduaries, fhould be frefh, 
 becaufe they lofe of their Virtue by keeping ; 
 and they fhould alfo be fine ground, becaufe 
 they would not otherwife intimately mix with- 
 the Honey or Syrup, nor fo readily part with 
 their Virtues in the Stomach, nor render the. 
 Medicine fo agreeable to the Eye. The common 
 Method of reducing thefe Powders to a fufficient 
 Degree of Finenefs, by the Mortar and Searce, 
 is faulty ; becaufe this Method expofes them too 
 long to the A( 5 lion of the open Air ; whereby 
 their more volatile and grateful Parts are carried, 
 off, whilft only the groffer are left behind : 
 it might therefore be proper to have a clofe 
 
 Engine 
 
Of common Pharmacy. 3 3 
 
 Engine contrived for the Purpofe, fo as to pre- 
 vent this ill Effefl. 
 
 52. Some Artifts grind their Powders {oxlmprorue 
 Eleduaries by Means of a Horfe-Mili ; but 
 Mill-Stones here wear off, and communicate a 
 gritty or ftony Matter to the Ingredients, fo as 
 
 to prove difagreeable in the Mouth, and fome- 
 what increafe the Bulk of the Medicine, with- 
 out adding to its Virtues. Nor is this Method, 
 by the Mill, free from the Inconvenience of the 
 Mortar *, for the finer or more fpiricuous Parts 
 of the Ingredients alfo fly off-, as is fenfibly found 
 by the whole Neighbourhood where any large 
 Quantity of the Ingredients for Venice-^^reacky 
 is ground by the common Horfe-Mill. 
 
 53. (3) The better Way doubtlefs is, by the 
 Means of Iron Rollers, moving oppofite to each 
 other in a clofe Box, to grind all the Ingredi- 
 ents, viz. the purified Gums, the Roots, Herbs, 
 Flowers, &c. along with the Honey and Wine, 
 after the Manner of the new invented Chocolate- 
 Engine \ for thus the fine, volatile, and aromatic 
 Parts of the Ingredients may, as well as the 
 groffer, been tangled with the Honey and Gums, 
 and all at once be mixed uniformly together in- 
 to a fmooth Mafs of a due Confiflence. 
 
 54. (4) But perhaps a much better, though 
 more troublefome. Method would be, to get 
 out the full Virtues of the Ingredients, without 
 any of their groffer Parts, in the Form of Ex- 
 tradls, effential C ils, and to mix thefe Oils, 
 Extradls, Gums, Rofins, together, with a 
 fuitable Proportion of Honey, fo as at once 
 to perfeff and concentrate the Medicine; which 
 might therefore be given in Dofes of an agree- 
 able Smallncfs, with all the Advantages that can 
 well be expedled. And the fame Method feems 
 alfo applicable to the making of Fills and Froches, 
 
 Z2 Experi- 
 
340 Lecture THE Fifteenth. 
 
 Oihyor Li 
 quid 
 fams. 
 
 CopjJi/^ent 
 
 Baljams, 
 
 Cerates* 
 
 Plaijlers. 
 
 The Expe- 
 riment ex- 
 tended. 
 
 And ap- 
 plied . 
 
 Experiment V. 
 
 1*106 heft Methods of making the compound Oils, 
 Unguents, Cerates, and Plaifters. 
 
 55 * twelve Ounces of fine Sailad- 
 
 Oil, half a Pint of Canary and half an 
 Ounce of Dragons-Blood reduced to fine Pow- 
 der ; thefe we boiled together, over a gentle 
 Fire, till the Wine was exhaled *, and thus ob- 
 ' tained a fine red Oil, or liquid Balfam. (2) To 
 one Half of this Oil we added four Ounces of 
 yellow Bees-Wax, fix Ounces of VeniceTurptn- 
 tine, and diflblved them together over the Fire; 
 then removing the Veflel into the Cold, we added 
 half an Ounce of Balfam Peru *, and thus made 
 a red Ungent, or better Sort of Lucatellush Bal- 
 fam. (3) To the other Half of the red Oil we 
 added a due Proportion of Wax; fo as when 
 cold to give it the Confiftence of a Cerate, or foft 
 Plaifter : And (4) By adding more Wax, and a 
 Proportion of Rofin, we made the Cerate into 
 a Plaifter of a hard Confiftence. 
 
 56. This Experiment at once ftiews us 
 the Method of preparing the compound Oils, 
 Unguents, Cerates, and Plaifters. The making 
 of compound Oils, in general, depends upon 
 boiling certain Ingredients, as particularly re- 
 cent Herbs well broiled, or elfe their Juices, 
 in Oil, till the aqueous Moifture is exhaled (as 
 the W^ine was in the prefent Experiment) and 
 the Plant become almoft crifp ; at which Time 
 the Veftel muft be removed from the Fire, and 
 the Oil fqueezed from the Herb by Means of a 
 Screw -Prefs. 
 
 57. This Oil is now to be fet over the Fire 
 again, that its remaining aqueous Moifture may 
 
 exhale. 
 
Of common Pharmacy. 341 
 
 exhale, and the groITer Parts of the Whole fub- 
 fide ; whereby the Oil will become not only 
 more beautiful in Colour, but alfo more durable, 
 or keep the better from turning mouldy. If the 
 Pan be not removed from the Fire before the 
 Herb is grown crifp, the Oil will be in Danger 
 of turning black, or being burnt ; which both 
 fpoils the Colour, and gives a difagreeable 
 Odour. If thefe Cautions are duly obferved, 
 the common compound Oils, by Deco^ 5 lion, may 
 be obtained in their intended Perfe6lion *, as Oil 
 6f Camomile, Elder, Rofes, Earth-Worms, ^c. 
 
 And after the fame Manner are feveral com- 
 pound Ointments made, by boiling Herbs along 
 with Lard, or Suet; as the Ointment of Elder, 
 Populeon, Nerve-Ointment, Melilot-Suet, Cfr. 
 
 58. The red Oil, obtained in the firft Step of 
 our prefent Experiment, fliews how liquid com- 
 pound Balfams are procurable by dilTolving re^ 
 finous Gums in Oil, over the Fire. And in 
 this Manner a fine Balfam may be made with 
 Gum Elemi^ and tinged beautifully red with 
 Dragons-Blood, or an Infufion of Alkanet Root 
 in Oil. And upon the fame Foundation might 
 feveral excellent liquid Balfams be prepared 
 for chirurgical Ufes. 
 
 59. Powder of Red Saunders has been com- 
 monly ufed, inftead of Dragons-Blood, in the 
 making of Lucatellus\ Balfam ; but doubtlefs 
 Dragons-Blood is much better fuited to the In- 
 tention of a Balfamic, a Healer, and Deter- 
 gent ; and alfo improves the Colour of the Me- 
 dicine : Tho’ Red Saunders may be made to give 
 a very good red Colour to the Balfam, by infu- 
 fing the Powder cold for two or three Days in 
 White Wine ; which opens the Body thereof, 
 exalts the Colour, and renders it communicable 
 with Advantage to the unduous Ingredients. 
 
 ' • Z 3 But 
 
342 L ECT U RE T HE Fl F T E EN T H. 
 
 But this End may be moreexpeditiouftyanfwercd 
 by infufing a little Alkanet-Root in the Oil. 
 
 60. The Confidence of an Unguent is given 
 either by ufing animal Fats, as Lard and Suet, 
 or by the Addition of Wax, Rofin, Pitch, dry 
 Powders, metalline Calces^ Cfr. and by adding 
 a fmaller or larger Proportion of thefe folid or 
 dry Ingredients, we obtain the Confidence of a 
 Cerate, or Plaider, refpecdively. When hare! 
 animal Fats are ufed, the Procefs differs not 
 from that for making the compound Oils^ ; and 
 •where Wax, Rofin, Cfr. are employed, the Ma- 
 nagement is the fame as in the prefent Experi- 
 ment, where the Confidence of the Oil is thick- 
 ened into that of a Balfam by Wax. 
 
 61. Yf hen dry Powders, or metalline 
 
 are ufed in the making of Ointments, the Pow- 
 ders diould be fredi and fine ground, and the 
 metalline Calces made more fubtile by Triture ; 
 after which the Whole may be mixed fmooth to- 
 gether, or beat up in a Mortar : And thus the 
 Unguentiim alburn^ Dejlccativum ruhrum^ Viapom- 
 pholygos^ &c. are readily prepared. 
 
 62. The Plaiders made with metalline 
 
 fuch as Diachylon^ and de Minio^ require no Wax 
 or Rofin to give them an empladic Confidence *, 
 the bare Solution of the metalline Calces^ or the 
 Litharge, and Red Lead, by boiling in the Oil, 
 being fufficient for the Purpofe. I'hus, if half 
 a Pound of Red Lead, half a Pint of Vinegar 
 or Water, and twelve Ounces of Oil, be boiled 
 together over a gentle Fire, with continual Stir- 
 ring, till the aqueous Moidure be confumed, 
 and the Red Lead entirely difiblved the Mat- 
 ter, when cold, will be of a hard, empladic 
 Confidence, and differently coloured, or red, 
 
 f See above §.55, 
 
 brown. 
 
Of common Pharmacy. 343 
 
 brown, or black, according as it was more or 
 Jefs boiled. 
 
 63. In the making of Plaifters with metalline 
 Powders and Oils, it is always proper to add 
 Water or other aqueous Liquor, to keep the 
 Mixture from burning, or turning black, before 
 the due Confidence is gained, or the requifite 
 Diffolution made. But here great Care muft be 
 had, not to throw in cold Water, if that added 
 at firft be exhaled before the Operation is finifh- 
 edj for this would be dangerous, bycaufingthe 
 Matter to crackle, fly about, and boil over with 
 great Violence : But if the Water be added in 
 the State of boiling, itoccafions no Tumult j and 
 may be thus uled with Safety. 
 
 64. When aromatic Species, native Balfams, 
 or eflTential Oils, are ordered in Unguents or ‘ 
 Plailters, Care muft be taken to add fuch Ingre- 
 dients towards the End of the Operation, when 
 the Veflel is removed from the Fire; becaufe 
 the Heat of boiling Oil, Cfc. would caufe the 
 fine aromatic or odoriferous Parts of the Ingre- 
 dients to exhale, and be loft to the Unguent or 
 Plaifter. The fame Caution fhould be likewife 
 extended to the Cantharides ufed in the Pajia 
 epifpajiica^ See, and to other Bodies of a delicate 
 Texture, whofe more efficacious Parts are ex- 
 haled by Heat. And by the due Obfervation of 
 thefe few Rules and Cautions, the common com- 
 pound Oils, Unguents, Cerates, and Plaifters, 
 may be made in confiderable Perfedion. 
 
 AXIOMS Pjjd CANONS. 
 
 I. We learn from the preceding Enquiry, 
 
 That fome Part of the Salts of Plants, as well 
 as their Oils, will rife by Diftillation with Wa- 
 ter, and give an acid or alkaline Nature to the 
 
 Z 4 (imple 
 
344 Lecture THE Fifteenth. 
 
 fimple Waters thus prepared, according to the 
 Nature of the Plant <3). 
 
 2. That no Simple Waters fhould bediftilled 
 fo low, as to bring over any remarkable acid 
 or alkaline Liquor from the Plant ; for fear of 
 mifchievous Effeds, or making fuch Waters 
 prove emetic or purgative, contrary to the In- 
 tention h), 
 
 3. That the Virtues of Simple Waters chiefly 
 depend upon their containing the eflential Oil 
 of the Plant r). 
 
 4. I'hat there are two Methods of perfeding 
 Simple Waters, Cohobation, and Fermen- 
 tation d). 
 
 5. That all Tindures and Infufions of In- 
 gredients, whofe principal Virtues depend upon 
 their lighter, or more fubtile and fpirituous. 
 Parts, fhould not be made with Heat, but in 
 the Cold e), 
 
 6. That if fuch Tindures or Infufions be 
 required rich and ftrong, they are to be made 
 fo, not by fuffering the Menftruum to remain 
 long upon the Ingredients, or by the Ufe of 
 Heat •, but by adding frefh Ingredients feveral 
 Times to the fame Liquor ; infufing them quick , 
 and each Time keeping put the Ingredients that 
 have once been ufed /). 
 
 7. That the Fire is apt to exhale, alter, or 
 confume the more fubtile and fpirituous Parts 
 of Vegetables ; and therefore unfit to be ufed 
 where thefe more delicate Parts are required^). 
 
 8. That the Bufinefs of Infufions and Tinc- 
 tures may be greatly improved by extrading 
 the efficacious, or more fpirituous Parts of Ve- 
 getables, unaltered in their Nature; yet con- 
 
 a) Exp, h ib. c) ib. ib. e) Exp, II. 
 
 /) ib. g) ib. 
 
 centratedj 
 
Of common Pharmacy. 345 
 
 centrated, or brought together into a moderate 
 compafs. 
 
 9. That rich Tin6lures may be extradled, 
 with Spirit of Wine, from the hardeft refinous 
 and gummy Bodies hitherto known, by Means 
 of fixed Alkali properly applied 
 
 10. That even aqueous Solutions may be 
 made of the fame Kind of Bodies, by Means of 
 the "Tartarum tartarizatum.^ or foluble Tartar b), 
 
 ji. That the Ways in common Ufe for the 
 making of Syrups, Eledluaries, compound Oils, 
 and Plaifters, are improveable by the Obfervance 
 of a few eafy Rules c). 
 
 12. That, therefore, there are grounds to 
 expedl fome Improvement of the common Phar- 
 macy, upon the footing it now ftands, barely 
 by perfecting the Methods of preparing the 
 Shop-Medicines in Ufe, without either retrench- 
 ing their Number, or introducing new ones; that 
 is, by reducing the Art to a greater Simplicity. 
 
 Exp, 11. h) ib. 0 Exp, III. IV. V. 
 
 LEG- 
 
[ 346 ] 
 
 lecture XVI. 
 
 CONTAINING 
 
 Attempts for reducing Pharmacy to a 
 
 greater degree of Simplicity and Efficacy, 
 
 fleSuB- % 1 \T ^ proceed to confider how Phar- 
 jea, y y macy may be reduced to Simplicity *, 
 which in Arts appears to include Perfedion. 
 
 *lhe Sim- 2. The Simplicity of Pharmacy feems to con- 
 fiidty of fifl; in fupplying a few powerful, parable, fafe, 
 Hartnacy.^^^ agreeable Medicines, for the Cure of Dif- 
 eafes. 
 
 3- Thofe verfed in the Hiftory of Phyfic ob- 
 fefve that Remedies have their Run, or Revo- 
 riarfi. lutions of Fate and Fortune ; many of them 
 being highly efteemed or magnified for a Sea- 
 fon, and afterwards thrown afide and negledted. 
 
 4. Not to mention the Medicines celebrated 
 by the Ancients, there are Numbers of others 
 which have had their Revolutions almoft within 
 our own Memory. The Elixir Proprietatis of 
 Paracelfus^ the Liquid Laudanum of Helmont^ the 
 Sal volatile oleofum of Sylvius^ the Aperitive Line- 
 ture of Moehius the Antiheflic of Poterius, the 
 Aqua henedifia^ or Vinum emeticum^ of Rulandus^ 
 the Bezoardic Powder of Sennertus^ Cerufe of An- 
 timony, and many more, have been extrava- 
 
 * That is, Spirit cf common Salt neutraliaed with Salt of 
 Tartar, and tinged with Red Rofes. 
 
 gantly 
 
347 
 
 Of fmple Pharmacy. 
 
 gant/ valued in their Time *, but arc now funk 
 in th Efteem of Pbyficians. And thus perhaps 
 our ^refent Opiates, our Salt of Vipers, our 
 Pea-s, our Bezoar, our Aurum fulminans^ See. 
 mayofe their Credit hereafter, or give Way to 
 othes of no greater Efficacy. 
 
 5 If we enquire into the Caufe of this Infta-^<»«/^ »/ 
 bilii in Pharmacy, it does not appear owing^^^"* 
 to te Medicines thcmfelves, but rather to the 
 Inatention, Levity, and RaffinefsofMen : In- 
 attetion, in not Efficiently regarding and dif- 
 tingiiffiing between the Kinds and Differences 
 of )iftempers and Conftitutions ; Levity, in 
 premtly changing one Medicine for another, 
 if th expeded Effed is not foon procured ; and 
 Rainefs, in ufing fuch Medicines as come re* 
 coimended by incompetent Judges, or unfair 
 Rerefenters. 
 
 t If the Caufe were owing to any Changes in 
 the Medicines themfelves, we could have little 
 Hoes^of redreffing the Evil *, but as it is owing 
 to urfelves, we are hence encouraged to look 
 outfor a Remedy. 
 
 . The Art of forming a found Judgment of R^^ula- 
 thtSuccefs and Virtues of Medicines is fo little //on. 
 knwn, that the Mind ufually fluduates therein, 
 as >eing deftitute of a fecure Foundation ; and 
 cofequently is led by Rumour, Opinion, and 
 Exmple, inftead of the true .Light arifing from 
 carful Obfervation,and well digefted Experience. 
 Wence it frequently happens that unlucky 
 Eents are attributed to ufeful Medicines ; whilft 
 fun Events were really owing to fome other 
 Cafe. 
 
 ). This Inattention is fucccedcd by Levity and 
 Rdinefs : For when a Medicine thus fails to 
 arwer the Expedation conceived of it, it is ufual 
 tcrejed it with Contempt, and immediately to 
 
 feizf 
 
3^8 Lecture the Sixteenth. 
 
 feize, in its Stead, the firft new one that comes 
 ftrongiy and vehemently recommended; which 
 again, after Trial, is frequently rejeded in the 
 fame Manner as the former. And thus the Lives 
 of Phyficians are often fpent in flying from one 
 Medicine to another, without fixing upon thofe 
 that are liable, or fuch whofe Virtues are duly 
 determined and afcertained. 
 
 9. This perverfe Temper or ill Habit of the 
 Mind muft therefore be cured ; or elfe Phyfi- 
 cians will continue to fludluate, and never bring 
 Pharmacy to a State of Perfecftion. 
 
 10. The Way of rectifying this ill Habit, we 
 apprehend, is to acquire a Competency of found 
 and fundamental medicinal Knowledge, by keep- 
 ing fleady to the Ufe of a few Ample Medicines ; 
 which are eafily prepared, no way hazardous, 
 and yet powerful in their EfleCls : And to fliew 
 the Way of procuring a few fuch Medicines, is 
 the Defign of our prefent LeClure. 
 
 1 1 . We judge that all Medicines are commo- 
 dioufly reducible to four general ClafiTes ; viz, 
 Evacuants,, Alter mils,, Strength eners,^ and ^ieters : 
 For as all the Caufes of Difeafes muft regard 
 either S^uantity,, ^ality,, or Motion,^ the Medi- 
 cines adapted to thefe Caufes will be either Eva- 
 cuants^ Alterants,, Augmenters,, or Appeafers of 
 Motion in the Body. 
 
 12. It muft, however, be obferved, that un- 
 der each of thefe general Tribes of Medicines 
 there are fome better adapted than others to the 
 Difeafes of particular Parts. Thus it is Matter 
 of Obfervation, that Mercury particularly affeCls 
 the falival Glands, Cantharides the Bladder, 
 Cfr. all which Remedies are to be colleCled, as 
 fo many particular Inftances, under our refpec- 
 tive general Heads of Medicines. And by duly 
 proceeding in this Manner, it fliould feem that 
 
 we 
 
Of fmple Pharmacy. 349 
 
 we might eafily fix upon a fmall Colle6lion of 
 Remedies, able, with a proper Regimen, to 
 cure the ordinary Difeafes. 
 
 13. At leaft, by throwing out of our prefent 
 Colledlion fuch as are certainly found to be of 
 fmall Efficacy, or certainly dangerous, we might 
 greatly retrench the prefent Set of Officinals^ and 
 bring the more ferviceable of them within the 
 Compafs of a 'portable Cheft, And with this View 
 we (hall endeavour to point out fome of the 
 more efficacious, parable, fafe, and agreeable 
 Evacuants, Alterants, Strengtheners, and Qui- 
 eters ; all along fixing a Mark upon thofe which 
 we take to be either unfafe or infignificant. 
 
 14. Our firft Experiment will fhew a Method 
 of procuring a fafe Emetic-, the fccond will fhew 
 how to prepare a fafe Purgative ; the third how 
 to prepare a fafe Perfpirative ; the fourth how 
 to prepare a fafe Alterant; the fifth how to 
 prepare an innocent Strengthener ; and the fixth 
 how to obtain a powerful Quieter, or Anodyne- 
 
 Ex periment I. 
 
 An eafy and Jimple Method of obtaining a fafe and 
 gentle Emetic, 
 
 15. Two Drams of the common white Ipeca-^^ 
 cuanha being reduced to fine Powder, and prepared, 
 fed for two or three Days in half a Pint of white 
 Lisbon Wine, in the Cold ; if the clear Liquor 
 
 be decanted, frefh Wine may be added to the 
 remaining Powder, fo as to extradt all the Vir- 
 tue, which it will thus yield to Wine in the Cold. 
 
 16. This Infufion of Ipecacuanha in Wine z'p-Ufes, 
 pears to be the mofi: fafe, gentle, and agreeable 
 Emetic hitherto known : Whence it may in moft 
 Cafes be properly fubftituted for the Vinum bene- 
 
 di^um 
 
350 Lecturethe Sixteenth. 
 
 di5lum^ the Tart arum emeticum^ and the other an- 
 timonial Emetics ; which arc all attended with 
 fome Degree of Virulency and Uncertainty in 
 their Operation. 
 
 Ipecacuan. I?- The Ipecacuanha Root, upon a proper 
 haanal^fed by Means of Water and Spirit of 
 Wine, is found to contain a dired faline and 
 refinous Part, whereof the faline is the larger ; 
 whence even an aqueous Infufion of the Root 
 will largely extradl its Virtues : So that a ftrong 
 White Wine feems a Menfiruum well adapted 
 to the Extradlion both of its faline and refinous 
 Parts, on account of the large Proportion of 
 Water, and a lefs of inflammable Spirit, that 
 it contains. Add to this, that Emetics, as well 
 as Purgatives, are found to a6l the freer, eafler, 
 and quicker, when joined with Wine, or other 
 ftrengthening fpirituous Vehicle. However, af- 
 ter both Water and Spirit of Wine have fuccef- 
 fively a(5ted upon this Powder, it ftill retains 
 fome Virtue *, fo that its Power is greateft when 
 given in Subftance : Whence our prefent Me- 
 thod of extradling a Tindure from it with Wine 
 only abates its Violence, and, in fome Mea- 
 fgre, moderates its Operation-, fo as to fit it for 
 weak Conftitutions, or render it almoft univer- 
 fally fafe. 
 
 Notimpro- 1 8 . This Root may, therefore, pafs for one 
 *vedby Qf thofe Simples which are little or nothing im- 
 emijiry, ^ chemical Treatment *, Nature fupply- 
 
 ing it almoft ready prepared to our Hands, fo as 
 to require no more than drying and Redudion 
 to Powder, at moft no more than a bare Infu- 
 fion in Wine, to render it a fafe Emetic. 
 
 Farther ^9* Now, being once pofleflTed of fuch an 
 Ufes, Emetic as this, which feems to include the Ex- 
 cellencies of all thofe of the lame Tribe, it is 
 doubtlefs proper to pradife the Method of Rejec- 
 tion 
 
Of fmple Pharmacy. 351 
 
 tim upon the reft ; or at lead to examine whe- 
 ther any of them deferve to be retained and 
 kept in the Shops. 
 
 20. We obferved above that the common Poifimvs 
 antimonial Emetics, of which there is a great 
 Variety, are virulent, or in fome Degree poilbn- 
 ous; and therefore not to be trufted, when fafer 
 can be procured to anfwer the End. ’Tis true, 
 fome Pradfitioners have ventured to give Arfenic 
 itfelf, in the Quantity of a few Grains, as an 
 Emetic •, and thus it fometimes operates violent- 
 ly, after the Manner of the emetic Preparations 
 of Antimony, which are nearly allied thereto. 
 
 But as we certainly know, by many fatal Inftan- 
 ces, that Arfenic is a virulent Poifon, even in 
 a fmall Dofe *, it may feem a Kind of Madnefs 
 to ufc it as an Emetic, when Ipecacuanha is at 
 Hand. And the lame is to be underftood, tho* 
 in a lefs Degree, of the Mercurius Glafs of 
 Antimony, Antimonial Cups, the Perpetual Pills, 
 the Sulphurs of Antimony, and indeed all other 
 draft ic Emetics ; which have a diretft virulent 
 Virtue, and, if given in too large a Dofe, pro- 
 duce poifonous Effedls. And here we do not 
 except emetic Tartar itfelf ; which, unlefs pru- 
 dently diluted with Wine or fome Cordial Wa- 
 ter, is apt to prove not only uncertain and chur- 
 lifh in its Operation, but fometimes virulent or 
 poifonous \ efpecially when exhibited in a dry 
 Form, as in that of Pills, Powder, or Bolus : 
 
 For all antimonial or other metalline Emetics, 
 coming in a dry Form into the Stomach, feem 
 to lodge in its membranous Coats, and ftimulacc 
 and corrode them ; fo as to occafion Spafms, 
 Convulfions, after the Manner of Poifons. 
 
 » §. 16. 
 
 21. And 
 
352 Lecture the Sixteenth. 
 
 Reguia- 21. And tho’ Solutions of Vitriol, Verdi- 
 tion. greafe, and various Preparations of Copper, 
 have been, and ftill continue to be, uf^ as 
 Emetics, and generally operate quick ; yet we can- 
 not judge fuch Preparations fafe, or any way 
 comparable to Ipecacuanha for Safety. And 
 even thefe cupreous Emetics, when given in a 
 large Dofe, have a corrofive Effect upon the 
 membranous Parts of the Stomach \ fo as to 
 prove, in a lefs Degree, poifonous. And thus, 
 if the whole Tribe of Emetics were carefully ex- 
 amined, and their Effects noted from compe- 
 tent Experience, we judge they would moft of 
 them be found unfafe or dangerous ; and con- 
 fequcntly deftrve to be banifhed the Shops, as 
 Emetics, whilft their Place may be fo well fup- 
 plied by Ipecacuanha. And this Method of Exa- 
 mination and Reje6lion being duly pradlifed, 
 might, as we apprehend, thin our Shops, and 
 reduce the Bulk of our Pharmacopoeias, to the 
 great Advantage of Pharmacy and Medicine. 
 
 Expe r iment II. 
 
 An eafy Method of procuring a fafe and effectual 
 Purgative, 
 
 ACathar- 22. If in a Quart of Dulwich-Y^s^tzc we dif- 
 ticprepa^ folve an Ounce of fine Manna, and half an 
 Ounce of black Tamarinds, then drain off the 
 Liquor clear, we fhall obtain an agreeable pur- 
 ging Pci fan, or cathartic Liquor, in a Dofe luf- 
 ficient for a full-grown Perfon of an ordinary 
 Conftitution •, the Whole being drank at feveral 
 Draughts, in the Space of about an Hour and 
 half, or two Hours. 
 
 23. It appears to be Matter of Obfervation, 
 that the common purging mineral Waters operate 
 
 with 
 
Of fmple Pharmacy. 353 
 
 with more Eafe, Gentlenefs, and Safety, than mi d 
 almoft any Cathartics of the Shops; and Q^\y Cathartic 
 require to be concentrated by boiling, or quick- 
 ened, in fome Cafes, to prevent the Trouble of 
 taking two or three Quarts for a Dole. Our pre- 
 fent Experiment, therefore, fliews the Method of 
 quickening thefc Waters, by the Addition of 
 innocent Purgatives ; fuch as are Manna ^ ’Tama- 
 rinds., Ej)fom-Salt.^ Tar tar urn tartarizatum.. Tar- 
 tarum vitriolatum^ &c. 
 
 24. The Shops and common DirpenfatoriesT'^^^/o/^;?/ 
 abound with purgative Medicines, many of to be re- 
 them draftic, or violent, and fome of them 
 rulent, or almolf poifbnous ; of which Kinds we 
 reckon Rofin of Jalap ..Elateriitm., Scammony., Gam- 
 boge., Coloquintida., Afarum.,^^c. ail which are of 
 a caullic Nature, when given crude and alone, 
 fo as to prove mortal in a large Dole : Y/hence 
 we apprehend that the crude and feparate Ufe 
 of all fuch Purgatives (hould be baniflied ; efpe 
 ciaily as there are numerous Inftances of their 
 deleterious and poifonous Etre(ft% and as we are 
 abundantly provided of fafer and more gentle 
 Kinds ; for Example, Rhubarb^ Manna., Tama- 
 rinds., Cajfia^ Cremor Tartari., Epfom-Salt ; and 
 particularly the purging mineral IVaters. Or \ f Qy. render- 
 the Ufe of the more violent purging Simples h^ed milder, 
 (till retained, let them at lead: be boiled in Wa- 
 ter ; which is a certain way of rendering them 
 milder, and difeharging a great Part of thar 
 Malignity. And for the purgative Rofins, par- 
 ticularly thofe of Jalap and Scammony, we 
 would recommend them to be ground fine, and 
 beat into a Pafte, with twice or thrice their 
 Quantity of blanched Almonds ; which, by their 
 oily Matter, dilTolve the Texture of thefc Ro- 
 fins, and render them more fafe and innocent 
 * See belcw Exp. III. 
 
354 Lecture the Sixteenth. 
 
 25. But we do not apprehend that the Art of 
 Medicine has any Occafion for thofe violent Pur- 
 gatives. Certainly violent Purgatives are feldom 
 proper, and generally prejudicial. If the Wronger 
 be ever required, we would, in (lead of the for- 
 mer virulent Kind, recommend the fimple Pow- 
 der of Jalap- Root *, vdiich is found to operate 
 much more mildly, and with greater Certainty 
 and EfFed, than its Rofin, Tindlure, or other 
 chemical Preparations of the Root ; which is 
 alfo the Cafe ot Mechoacan and Rhubarb. 
 
 26. We defire it may be remembered, that 
 the deleterious or poifonous Nature of the vio- 
 lent Purgatives above mentioned is much greater 
 in the Body than that of the poifonous Emetics ; 
 doubtlefs becaufe fome Part of thefe Emetics is 
 foon thrown up again by the Stomach •, whereas 
 the Purgatives defeend to the Inteftines, and 
 
 - mix with the Juices ol the Body : Whence we 
 have a fironger Reafon for rejeding the Ufe of 
 thefe virulent Purgatives, than the Ufe of the 
 virulent Emetics. 
 
 27. And thus we conceive the Matter of Pur- 
 iion. gaiives may be reduced to a tolerable Degree of 
 
 Simplicity *, yet fo as to leave Variety enough for 
 fuiting the diiierent Difeafes and Conftitutions 
 where Purging is required. The Nature of our 
 Defign will only permit us to indicate, as we go 
 along, the Pleads of this general Enquiry into 
 the Means of reducing Pharmacy to an elegant 
 and uieful Simplicity-, the Jntrodudion whereof 
 is not to be expeded from private Hands. 
 
 Ex P E R I- 
 
Of fimple Pharmacy, 
 
 355 
 
 Experiment III; 
 
 -A facile and fimple Method of preparing a fafe and 
 effe^ual Sudorific, 
 
 28. If an Ounce of refined Cam phi re be beat,^ 
 
 and ground, in a Marble Mortar, with iv^ofic prepa- 
 Ounces of blanched Almonds *, the Camphire'"^^’ 
 will be thus fubtilly divided^ and brought into 
 an uniform Mafs, fit for the forming of Pills, 
 Bolufes, Cfc. fo as to be commodioufly taken 
 in the Way of a Sudorific, Dil’cutitnr, or Per- 
 fpirative Remedy *, the Dofe whereof may be 
 affigned betwixt the Limits of three Grains and 
 forty. 
 
 29. Sudorific, Perfpirative, and Alexiphar-L^^j^ 
 mic Medicines, make a large Part of the com- 
 mon Difpenfatories : We judge that their Places 
 may be advantageoufly fupplied by a lew power- 
 ful ones of approved Virtues \ ati'iong which we 
 edecm this of Camphire as a principal one, or 
 
 at leaft fuperior to Gafcoign^ Powder, Lapis Con- 
 tray erv^e,, Bezoar,^ whole Virtues at bed ap- 
 pear to be fmall. 
 
 30. We are fenfible that the Qualities ofCam- 
 phire are not univcrfally agreed on by Phyficians ; 
 
 Ibme efteeming it hot, and others cold *, fome of 
 great, and others of little Efficacy. However, the Cafe 
 is not to be decided by Authorities, but Expe- 
 rience 5 which feems to declare that Camphire 
 is one of the moll powerfu’, mod immediate, 
 and mod innocent Perfpiratives, SudoriBcs, and 
 Alexipharmics hitherto known : For a large Dole 
 of it, luppofe a Scruple or more, being didolved 
 in Spirit of Wine, and given to a healthy Perfon, 
 does not increafe the Puife, or excite a prseter- 
 natural Heat ^ but rather caufes a remarkable 
 
 A a 2 Ccolnefs 
 
35 ^ 
 
 Farther 
 
 Ufa. 
 
 Lecture the Sixteenth. 
 
 Coolnefs and Compofure, with a gentle Sweating, 
 or Increafe o[ Perlpiration. So little have the 
 Virtues of this Medicine been underdood ; or 
 fo little can the Virtues of Medicines be dedu*' 
 ced from their apparent Properties, or from rea- 
 foning a friori ! 
 
 31. The natural and medicinal H ftory of this 
 Drug well defcrves to be traced : Ic appears to 
 be an dfential Oil, of peculiar Properties ; tho’ 
 fome would have it a Rofin, and others a Gum. 
 Certainly it Hands alone, as a Thing [ui generis \ 
 or a Body wherein the Nature of Rohns, Gums, 
 and eiTential Oils, all meet in fome Degree. It 
 is perhaps one of the mod difcutient and fubtile 
 Remedies hitherto difcovered : Whence it proves 
 highly anodyne, perfpirative, and prefervatory. 
 And we judge, from certain Obfervations and 
 Experiments, that if the full Virtues of this Con- 
 crete, both internal and external, were I'uffi- 
 ciently known, ic might fupply the Place of nu- 
 merous other Drugs and Preparations, to the 
 Eafc and Advantage of Pharmacy. 
 
 32. In particular, we would recommend this 
 Medicine to be ukd inftead of the common fu- 
 dorific Decodlions of the Woods, in Cafes both 
 of the recent and inveterate Lues Venerea : Ic 
 may aifo be advantageoufly mixed along with 
 the Ballams, or fine Turpentines, commonly 
 ufed at the dole of that Didemper. In fhort, 
 we recommend it in all infiammatory, putrid, 
 pedilential, and even maniacal, Difeafes. And 
 whoever has the Secret of prudently joining this 
 fimple Medicine along with Nitre, may, as we 
 apprehend, perform Cures fcarce to be expeded 
 from other Medicines frequently ufed for the 
 fame Purpofes. 
 
 Ex P E R I- 
 
Of fmple Pharmacy. 
 
 357 
 
 Experiment IV. 
 
 An eafy and Jimple Method of procuring a fafe and 
 powerful Alterant. 
 
 33. If an Ounce of well purified Nitre, 
 
 and two Scruples of Cochineal in Powder, ht am from 
 boiled in five or fix Ounces of Water *, and 
 Solution be filtred, and afterwards evaporated 
 to Drinefs, keeping the Matter fiirring as it 
 thickens-, a fine red or pu^'plc Powder will be 
 left behind *, that is, the Nitre will be thus dif- 
 guifed, aud reduced to a P'orm fit for taking in 
 the Way of Bolus, Powder, or Solution, with any 
 convenient Vehicle. 
 
 34. Nitre thus prepared, in order to conceal 
 fo common a Thing, we judge to be an extremely 
 fafe and ufeful Alteranr, capable of produ- 
 cing confiderable Efiedis in the Body, without 
 caufing any difturbance, or fenfible Evacuation, 
 unlefs in the Way of a Diuretre in which 
 Refped: it operates as an Evacuant. 
 
 35. It is remarkable of Nitre, that it may 
 with Safety be injeded into the Blood. Mal- 
 pighi injedled fix Ounces of its Solution into the 
 Jugular Vein of a Dog, without obferving any 
 other Effedl than its proving diuretic. It is far- 
 ther obfervable of- it that it heightens the florid 
 Colour of extravafated Blood, and excellently 
 prelerves it from Putrefadfcion yet does not li- 
 quify frefh and warm Blood, as has b^en ima- 
 gined, but fomewhat thickens it, almofl in the 
 Manner of a Mucilage : Which may give us the 
 phyiical Reafon of many of its EfFecfls in rhe Body; 
 as particularly its allaying Inflammations and 
 P'evers, its (lopping FIiEmorrhag?s, curing the 
 Spitting of Blood, ^c, 
 
 A a 3 36. If 
 
35 ^ 
 
 Lecture the Sixteenth. 
 
 36 If the m'^dicinal Virtues of this fimple 
 Medicine were to be enumerated, as they fland 
 coniirmed by competent Exp:^irience, perhaps 
 they would prove more numerous than thofe of 
 almoH: any Medicine hitherto known. It has 
 been found ferviceable in the Stone, and Stop- 
 pages of Urine in Deliriums, in malignant 
 Fevers, in Diarrhoeas attending the confluent 
 Small Pox, fo as to prove a Kind of general 
 Remedy. And as all thcfe Excellencies of the 
 Medicine are joined with that defirable Property 
 oi being innocent, or Icarce any Way prejudicial 
 to the Body *, it may feem flrange that it fliould 
 be fo little ufed, or that Medicines no Way com- 
 parable to itfliould be preferred before it. 
 
 Whence 37- Poffibly the mixing of Nitre with other 
 aifejteemeeiMcdiCAncs may have occafioned its Virtues to be 
 lels known, or obferved ; perhaps that Humour 
 oi changing Medicines, almofl: every Day, may 
 not have given it the Opportunity oi fliewing it- 
 felf j bat chiefly that flrange Method of jum* 
 bling many Simples together in one Medicine, 
 feenis to hive prevented the due noting of the 
 EfFeds of this and other Ample Remedies. We, 
 therefore,' wifii that the Mtiiidnal Hifiory of Nitre 
 were drav/n up, with Care and Judgment ; as 
 be'og peifuaded, that both Pharmacy and Me- 
 dicine might, by means thereof, be brought much 
 nearer to Simplicity and Perfedion than they 
 are at prufent. 
 
 Experiment V. 
 
 An artificial Method of preparing a powerful and 
 innocent Strengthener. 
 
 38. We put half a Pound of the beft Peruvian 
 Bark, reduced to fine Powder, into a proper 
 Giafs, and poured upon it two Quarts of Spirit 
 
 of 
 
Of fmple Pharmacy. ' 359 
 
 of Wine ; then Hiaking them vveil together, {tt^ne£en- 
 them to digefl in a Saiid-heat for two or rh»ee^'^'^ 
 Days, tili the Spirit of Wine appeared of ^ 
 deep red Colour, inclining to t'urple. We 
 now ftrained the Tinflure through a clofe 
 Linen, and committed the F^ces at laff to the 
 Prefs* Then returning the Prefilngs, or re- 
 maining Powder, into the fame Glafs, we pour- 
 ed thereto tv;o Quarts of drong White Wine, 
 and again fet the Matter to digeft for two or 
 three Days ; then drained as before. After this 
 we put the two Liquors into a Glafs-Body, and 
 didilled oft a large Part of the Spirit of Wine ; 
 then evaporated the Remainder in a glazed Vef- 
 fel, taking Care to keep the Matter dirring, and 
 wadiing down, with fome of the Spirit of Wine, 
 the (efinous Parts that adhered to the Sides of 
 the Vedel. When the Matter began to grow 
 thick, we added to it three ‘Ounces of the Syrup 
 of Orange-Peel ; and thus brought the Whole to 
 the Confidence of an Extradt, 
 
 39. This Method of excra6ling the Virtues OijtsH.fiory 
 the Bark is the Invention of M. Charas *, who ex- 
 perienced its Succefs in a large Pradlice for fifteen 
 Years, wherein he never found it fail him, for 
 
 the Cure of all Sorts of Intermittents. We have 
 ourfelves alfo had a competent Experience of its 
 Succefs ; and found it anfwer better than any 
 other Preparation of the Bark we have feen : 
 
 Whence we judge it the bed Manner hitherto 
 known of preparing an Extracl: from the Bark, 
 fo as to render it more innocent and effedtuaL 
 
 40. The Procefs was formed upon this Suppo- Rationale: 
 fition, That the Bark contained a Rodn and a 
 
 Salt for its principal component Parts •, to the 
 Extradlion whereof the two Mendruums are well 
 adapted. And, in Efredt, we find that Spirit of 
 W'ine does extradt a Kind of Rodn from the 
 
 A a 4 Bark ; 
 
360 
 
 J^egimen. 
 
 El'Sol'ac- 
 c ha rums 
 recommcn 
 did. 
 
 Lecture the Sixteenth. 
 
 *, and Wine fuch a Part as renders it able 
 to cure iome Kinds of Intermittcncs in certain 
 Conkirutions : Whence thefe two Menlfruums, 
 doLibilefs, take up the more medicinal l^arts of 
 this Subfiance, leaving its more woody or fibrous 
 Part behind •, which }:rjbably occafions that 
 Stoppage and troubiefome Weight at the Stomach 
 we otcen hear complained of after taking large 
 Quantities of the Bark in Subifance. 
 
 41. The two finer and more medicinal Parts 
 of the Bark being thus extradled, they are com- 
 rnodioufly joined together again by the Interpo- 
 fition of the Sugar contamed in the Syrup ; fo 
 as to form an elegant Whole, that may be aro- 
 matized at Pleafure with the eficntial Oil of 
 Mint, Cinnamon, or Cloves. 
 
 42. The Dofe, and xMtthod of exhibiting this 
 Preparation of the Bark, are the fame as the 
 common ^ and though a much larger Dofe fliould 
 be given, it has not been found to produce any 
 ill Effedl Ti'he U^e of this Medicine is alfo at- 
 tended with a quicker Recovery of the natural 
 Complexion, Vjgour, and Phelhnefs, than the 
 Ufe of the crude Bade. And as the Medicine 
 appears to be thus rendered fo powerful and 
 innocent, perhaps it may be proper to try it 
 alfo in fomc other weakening Dilden'ipers, befides 
 Intermitting Fevers. 
 
 43. There are many other powerful and in- 
 nocent Screngtheners, befides this Prep^aration 
 
 "of the Bark •, among the principal whereof come 
 the capital Aromatics, Cmnamon, Cloves, Nut- 
 meg ; or rather their efiTcntial Ods *, which being 
 made into Elieofac char urns,, afford as poteiU Cor- 
 dial Medicines, in a commodious Form, as can 
 well be expected. But if more compounded 
 Medicines are required, v/e would recommend 
 the Ule of a cGm^Q'tnd EU'faccharum^ confining 
 
 of 
 
361 
 
 Of fmple Pharmacy. 
 
 of a few le(e6t aromatic Oils, and the richeft 
 Gums and Balfams, as one general Cordial, or 
 compound Screngthener. And thus a Medicine 
 might be cafily contrived, that fhould colledt 
 in itfelf, or concentrate, the Cordial Virtues 
 difperfed in feveral capital Ingredients. Thus 
 for Example, Camphire, Balfam Balm of 
 
 Gilead., the eflential Oils of Cinnamon, Lignum 
 Aloes., Myrrh, iAc. are all homogeneous, and 
 capable of being united either alone, or with 
 Spirit of Wine, or Sugar ; fo as to be given 
 with alldefirablc Advantage and Convenience. 
 
 Experiment VI. 
 
 A ready Method of procuring a fafe §uieter^ or 
 Anodyne. 
 
 44. We took half an Ounce of Opium, z.x\diOptum^re- 
 didblved it- with a gentle Heat in five or fix times/^''^^*. 
 its own Quantity of fair Water *, then {training 
 
 the Solution, and exhaling away the fuperfluous 
 Moifiure, in a temperate Sand-heat, we reduced 
 the Matter 10 a dry Subftance *, which being 
 ground in a Glafs-Mortar, with twice its own 
 Weight of hard Loaf-Sugar, Teems to afford us 
 one of the belt or mildeft Preparations of Opium ; 
 and may be given from one Grain to three or 
 four for a Dole. 
 
 45. By diffolving the Opium in Water, we^^j. 
 get rid of its more grofs and refinous Parts, 
 which are found much more pernicious than the 
 reft ; and by dividing its Parts afterwards, 
 with Sugar, we render the Medicine more uni- 
 form, rdbluble, and mifcible with the animal 
 Fluids ; and can thus the better adjuft its Dofe. 
 
 But (till this Medicine is not without Tome 
 pernicious Property •, nor is there any way 
 
 known 
 
362 
 
 Lecture the Sixteenth. 
 
 known to render the Ufe of Opium perfe 61 :ly 
 iafe and innocent in all Conftitutions : For if a 
 large Dofe of it be given, it is apt to dilfurb 
 cr cloud the Head, caufe a Vertigo, Delirium, 
 or Convulfions •, in particular, it proves preju- 
 dicial to the Stomach and intellines, which it 
 is apt to inflame and fphacdate ; thus ading, 
 in fome D gree, as a Poifon : Whence a better 
 Method of correding it fbould be endeavoured 
 after, or a more innocent Remedy be ufed in 
 its Stead. A Mixture of Nitre and Camphire, 
 we apprehend, may fupply its Place on many 
 Occafions, without any P'ear of Danger or Incon- 
 venience. 
 
 Regula- ^5, Thus we have endeavoured to give an 
 *pi of a Ample and Iafe Preparation in each 
 
 ^ '^'ot the four general Tribes under which we con- 
 
 ceive all Medicines may be commodiouOy ran- 
 ged •, viz. Evacuants, Alterants, Strengtheners, 
 and Quieters. If the Method we have here ob- 
 ferved were purfued to its due Length, it might, 
 doubtlefs, terminate in the certain Difcovery of 
 a few Ample, elegant, innocent, and powerful 
 Remedies ; at ieall it would enable us to throw 
 our, as dangerous, noxious, or poifonous, a 
 large Part of our prefent Materia medica., and 
 pharmaceutical Preparations ; and a confiderable 
 Part thereof, as almofl: ufelefs, or inAgniAcant : 
 Whence fome tolerable Degree of Per fed ion in 
 Pharmacy might be obtained. 
 
 47. Thus all the Medicines that have Lead 
 in their Compofition are fcarce to be trufted for 
 internal Ufe. We have various Inftances of the 
 poifonous Nature of this Metal ; as particularly 
 among the Workmen at the White-Lead Houfes, 
 the Colourmen, or Grinders of Cerufe, and 
 thofe who any way work in Lead. And it were 
 fufiicient to banifli the frequent internal Ufe of 
 
 Saccha- 
 
Of fimple Pharmacy. 
 
 Saccharum Saturni, the Tin5iura anttphthefica., &c. 
 to read, in the Mifcelianea curiofa how many 
 Men were poifoned by drinking acid Wine 
 rendered Tweet v/ith Litharge. 
 
 48 . But Metals do not acl in the Body till 
 they are once diffulved : Whence crude Mer- 
 cury, fwallo'A^ed in large Quantities, proves 
 harmlefs, through the Want of a Menftruum in 
 the Stomach, to diffblve it. But when crude 
 Mercury is diflblved by its proper Menftruum, 
 as in the Preparation of Mercury- Sublimate, 
 we fee it becomes one of the ftrongeft Poi- 
 fons. Lead, Iron, and Copper, being much 
 more eafily diftblved than Quickfilver, are fel- 
 dom taken without fome remarkable EfFedt ; 
 which mu ft neceiTarily prove the greater, the 
 more of an acid, or, in the Cafe of Copper, 
 even alkaline Humour, is lodged in the Stomach 
 or Inteftines : Whence we derive a phyfical Rea- 
 fon why thefe Metals often produce different 
 Effc61;s in different Conftitutions. The internal 
 Ufe of the Crjftah of though fometimes 
 
 fuccefsfully given in dropfical Cafes, ffiould 
 hardly be trufted, on account of their corrofive 
 Acrimony •, which has fometimes occafioned 
 bloody Stools, and ext'feme Weaknefs. The 
 common Tindlures of Copper, and Solutions of 
 blue Vitriol, can fcarce be taken internally with' 
 Safety *, as being not only emetic, but in fome 
 Degree corrofive and poifonous. Even the Au~ 
 rum fiilminans^ though highly efteemed by fome 
 as an internal Medicine, cannot be fafely given, 
 unlefs it has been firft well wafhed from its 
 Salts, and does not meet with a fuitable acid 
 Solvent in the Stomach : For in both thefe Cafes 
 it may have dire Effeds j of which there have 
 
 * Decad, III. Obf. 30. 
 
 been 
 
Lecture the Sixteenth. 
 
 been remarLtble Inftances. Iron and Tin have 
 rot been found fo pernicious to the Body, but 
 ratii.r bcntn.ial ; erpecially Iron, when pru- 
 dently prepared and ufed. Indeed, of all the 
 Metals iron ferms to be the mod innocent, and 
 iLfncicncly powerful, rho’ diflblved in fo weak a 
 Mend uum as Wine. And as this is the Refulc 
 of o .r Method of Rejcdion applied to Metals 
 and metalline Preparations, fo we apprehend that 
 if the fame Method were applied to the whole 
 Materia medica^ there would thence refulc the 
 difeovery of fafe and powerful Medicines for the 
 Cure of all ordinary Difeafes : Whence we would 
 recommend this Kind of Procedure to thofe who 
 regard the Improvement of Pharmacy and Phyfic. 
 
 t 
 
 AXIOMS and CANONS. 
 
 1. We learn from the preceding Enquiry, 
 That certain Simples are naturally better pre- 
 pared for medicinal Ufe, than by the common 
 chemical Treatment *, fuch in particular are Ipe- 
 cacuanha, Jalap, Rhubarb, Mechoacan, 
 Tables, or Catalogues, of which Kind of Simples 
 ought to be formed, in order to abridge and 
 perfedV Pharmacy a), 
 
 2. That moll of the Emetics in common 
 Ufc, efpecially the antimonial Kind, are virulent 
 and fomewhat poifonous, compared to that milder 
 one of Ipecacuanha h.) 
 
 3. That many of the common violent Purga- 
 tives are of an adually poifonous Nature, and 
 therefore fhould be artificially correded, or elfe 
 make room for more innocent Kinds to be ufed 
 in their Stead ; particularly the purging mineral 
 Waters^ Manna, Rhubarb, Cfr. 
 
Of fmple Pharmacy. 
 
 4. That the more violent and poifonous Pur- 
 gatives, -fuch as E!aterium, Coloquintida, Scam- 
 mony, Hellebore, may have their poiibnous 
 Quality mitigated, or taken away, by boiling in 
 Water and other Expedients a). 
 
 5. That the Effects of the poifonous Purgatives 
 are conGderably greater in the Body than the 
 Effedfs of the poifonous Emetics^). 
 
 6. That the two principal Tribes of Evacu- 
 ants, viz. Purgatives and Emetics, are reducible 
 to a few fimple and eafy Preparations c). 
 
 7. That Camphire has confiderable Virtues, 
 as a Perfpirative, Sudorific, and Refolver ; be- 
 ing capable of uniting with oily' Subftance^ and 
 bearing a Relation to effential Oils, Rofins, 
 Gums, and Balfams d), 
 
 8. That purified Nitre has many medicinal 
 Virtues *, fo as advantageoufly to fupply the Place 
 of numerous other Medicines e). 
 
 9. That this purified Nitre has a great Power 
 of preferving the Blood uncorrupted, frefh, and 
 florid /). 
 
 10. That many of the medicinal Virtues of 
 Nitre do not depend upon its liquifying, but 
 rather upon its jellying the Bloody). 
 
 11. That the Pcrfedtion of Phyfic and Phar- 
 macy may have a confiderable Dependence upon 
 the medicinal Hiftory of Nitre h), 
 
 12. That the Peruvian Bark may be rendered 
 more innocent and effcdual than when given in 
 Subftance, for the Cure of Intermittents, Cfc. 
 by Means of a proper Treatment, or by extrad- 
 ing and uniting its faline and refinous Parts 
 with a fuitable intermediate Subftance /). 
 
 13. That this Bark appears to contain three 
 very different Parts in a loofe Texture ; viz. a 
 rofin, a fait, and a woody Subftance k), 
 
 «) Exp. II. b') ib. f) Exp. I. III. d) Exp. in. 
 ij Exp. IV. f) ib. g) ib. h)\\). i) Exp.V. h) ib. 
 
 14, That 
 
366 Le CT UR E T H E SiXT E E NT H. 
 
 14. That pofTibly the refinoiis and faline Ex- 
 trads of the Bark may be ferviceable in curing 
 more Difcafes bclicies Intermitting Fevers ; and 
 that probably the frequent Failure of the com- 
 mon Infufions and Extrads of this Drug are 
 owing to their containing much of its refinous 
 Part without the laline one, or the faline Part 
 without much of the rdinous •, and not a due 
 Mixture and full Proportion of the two, as they 
 are naturally found in the Bark itfelf : Whence 
 the Subftance has generally proved more elFedual 
 than any of thofe imperfed Extrads, Tinctures, 
 or Infufions d), 
 
 15. That powerful Strengtheners, or Cordi- ~ 
 als, are obtainable from a Mixture of the richeft 
 Balfams, and effential vegetable Oils h'). 
 
 16. That Opium may be fo prepared as to 
 become more innocent than in the common Me- 
 thods of treating it c), 
 
 17. That a lefs noxious Quieter is wanted 
 than Opium, and may, in fome Meafurc, be 
 fupphed by Nitre and Camphirei). 
 
 18. That no Preparation of I,ead can be long 
 or freely ufed internally, without confiderabie 
 Hazard 
 
 19. That the common Solutions and Prepara- 
 tions of Copper, Silver, Gold, and Mercury, 
 are hardly proper for internal Uie; nor even 
 Tin and Iron, unlcfs prudently prepared with 
 gentle Menftruums, and cautioully given/). 
 
 20. That there are rational Grounds to exped 
 fome confiderabie Improvements in the prelent 
 State of Pharmacy and Medicine, by a due En- 
 quiry, and a proper Ufe of the Means conducive 
 to this End^). 
 
 a) Exp, V. b) ib. c) Exp. VI. d) ib. . e) ib. 
 
 /) ^l^s whole Le^iure, pajjim. 
 
 LECTURE 
 
( 3^7 ) 
 
 LECTURE XVII. 
 
 CONTAINING 
 
 Mineralog Y ; or the Art of Mining: 
 
 With the previous Operations to Metal- 
 lurgy; viz. Roafting, Stampings Wafh-- 
 ingy and the Bufinejs of Fluxes, 
 
 I. E are now entering upon a large, and 
 
 V V extremely ufeful Branch of Chemiftry \jeSi, 
 the Bufinefs of Mineralogy and Metallurgy, 
 
 2. By Mineralogy we underfland that previous 
 
 Part of Metallurgy, v/hich teaches the Ways o{logyi<^hat, 
 finding, judging, and digging Mines ; with the 
 Ufes of Salts and Earths for making Fluxes, in 
 order to the afiaying and fmdting of Ores for 
 their Metals. 
 
 3. By Metallurgy we underfland the Perform- 
 ance of thofe feveral Operations required to fe-i'i’» 
 parate Metals from their Ores, for the Ufes of 
 Life. And according to this Diflindion we fhall 
 beflow one Ledlure upon Mineralogy^ and another 
 upon Metallurgy^ in the Senfe we have here ex- 
 plained them. 
 
 4. Mineralogy is an Art that requires a confi- j^etimfites 
 derable Compafs of Knowledge, before it can h^toMinera- 
 pra6tiled to Advantage: For as this Art includes 
 
 the Difcovery, Sinking, and Working of Mines ; 
 it requires a competent Skill in the Nature, Efflu- 
 via, and Effeds of mineral Matters, whether 
 Earths, Salts, Sulphurs, Stones, Ores, Bitu- 
 mens, 
 
368 Lecture THE Seventeenth. 
 
 mens, Gems, or Metals. It like wife requires a 
 Knowledge of the internal Scrudure of the Earth, 
 and its various Strata \ with a competent Skill in 
 fubterraneOLis Architedure, Menfuration, Ely- 
 draulics, Levelling, and Mechanics •, without 
 which we can never judge what Mountain, 
 Plain, or Valley, is proper to be dug; in what 
 Manner to dig it ; how to difcharge the Water 
 that may flow in upon the Works ; how the 
 Beds of Ore and Stone will dip, or run; how 
 the various Kinds of Earths, Marble, and ocher 
 mineral or metallic Matters, are to be cut 
 through, or broken ; or how the general Procefs 
 of Mining fhould be conduded, in order to 
 procure, with the leaft Expence, or bring to 
 open Day, the principal Matter or Ore re- 
 quired. 
 
 ^alijica^ 5 . And even when all thefe Difficulties a^e 
 tions of a conquered, no more than half the Work is cffed- 
 MetaUiJi. ed ; and ftill the End can never be obtained 
 without a tolerably exad Knowledge of fcveral 
 chemical Operations ; viz. Trituration, Torre- 
 fadion, Lotion, Calcination, Cementation, Fu- 
 fion. Amalgamation, Vitrification, Sublimation, 
 Diftillation, and the like : Whence it might be 
 laid down as a Rule, That every direding Me- 
 talfift fhould not only be tolerably verfed in the 
 feveral Parts of Natural Philofophy, but parti- 
 cularly be well acquainted with Chemijiry, 
 
 6: And perhaps it may not be improper to 
 intimate, that many metallurg'cal Attempts have 
 mifcarried, merely for Want of a competent Skill 
 to condud therrj. The under Workmen in this 
 Way are generally a head-ftrong, ignorant Peo- 
 ple,- that cannot be managed without the Uie of 
 Ibme good political Rules, and a Knowledge 
 much fuperior to their own. Yet how little 
 foever the Art of Mineralogy may have been 
 
 under- 
 
3^9 
 
 underftood, Hiflory afiords us numerous Exam- TheSutce/s 
 pies of plentiful Poi tunes and irnrnenfe Ticafures 
 raifed from mines, as well by private Perions, 
 as by particular States and Knigdoms. But the 
 Vulgar, and even Pbilofophers unverfed in 
 Trade, generally reckon the Bufinds of Mining 
 unprofperous, and at bell precarious and un- 
 certain j eipecially when compared with Agri- 
 culture, or other Arts exercifed more in the 
 open Day. 
 
 7. The Truth is. Mines are liable to many 
 Contingencies ; being fometimes poor, fome- 
 times foqn exhauftible, fometimes fubjed: to 
 be drowned, efpecially when deep, and fome- 
 times hard to trace. Yet there are many In- 
 ftances of Mines proving highly advantageous 
 for hundreds of Years. The Mines of Potqfi 
 are, to this Day, worked with nearly the fame 
 Succefs as at fird; ; the Gold Mines of Crem- 
 nitz have been worked almoft thefe thoufand 
 Years ; and our Cornijh Tin-Mines are extreme- 
 ly ancient. In general, the Profit of Mines, 
 compared with that of Agriculture, is immenfe- 
 ly greater in the fame Time, fo as to compen- 
 fate largely for its Uncertainty. Even Lead- 
 Mines generally yield twice or thrice the Re- 
 turns of the richeft Soils, cultivated in the ordi- 
 nary Manner, either by Nature or Art. What 
 then fliall we fay of the Mines that are rich in 
 the nobler Metals ? The neat Profit of the Sil- 
 ver alone, dug in the Mifnian Silver-Mines of 
 Saxony^ in the Space of eighty Years, is computed 
 at an amazing Sum 
 
 8. Many Mines have been difeovered by Ac- Accidental 
 cident. A Torrent firfi: laid open a rich Vein 
 
 Oi the Silver- Mine at Friberg in Germany. Some- 
 
 * See Peit\ Albin. in Chronic. Mifn. Miner. German. 
 
 E b 
 
 times 
 
370 Lecture'the Seventeenth. 
 
 times a violent Wind, by blowing up Trees, or 
 overturning Rocks, has difcovered a Mine. The 
 fame has happened by violent Showers, Earth- 
 quakes, T hunder, the firing of Woods, or even 
 the Stroke of a Plough-Share, or a Horfe’s 
 Hoof. 
 
 fhe Art of 9. The Art of Mining does not wait for thefe 
 hiining, favourable Accidents *, but diredtly goes upon the 
 Search and Difeovery of fuch mineral Veins, 
 Ores, or Sands, as may be worth the working 
 for Metal. 
 
 Ho^tohe 10. The artificial inveftigation and Difeovery 
 fraaifed. of Mines depends upon a particular Sagacity, or 
 an acquired Habit of judging, from particular 
 Signs, that metallic Matters are contained in cer- 
 tain Parts of the Earth, not far below its Surface. 
 Signs of a II. The. principal Signs of a latent metallic 
 Mine. Vein feem reducible to general Heads *, fuch as 
 
 (1) the appearance of certain mineral Waters ; 
 
 (2) the Difcolourarion of the Trees or Grafs ; 
 
 (3) Pieces of Ore on the Surface of the Ground •, 
 
 (4) the Rife of warm Exhalations •, (5) metallic 
 Sands, and the like : All which are fo many 
 Encouragem.ents for making a ftriefer Search 
 near the Places where any Thing of this Kind 
 appears. Whence Rules of Practice might be 
 formed for reducing this Art to a greater Cer- 
 tainty. 
 
 TV Art of 12 But v^^hen no evident Signs of a Mine ap- 
 Boring. pear, the fleilful Mineralifl ufuaily bores the 
 Earth in fuch Places as, from fome Analogy 
 of Knowledge, gained by Experience (or by ob- 
 ferving the Situation, Courfe, or Nature of other 
 Mines) he judges may contain Metal. 
 
 13, This Method of Boring confifls in the Ufe 
 of^ Set of Scooping Irons, made with Joints, fo 
 as to be lengthened at Pleafure, and thruft down 
 to a considerable Depth below the Surface of the 
 
 Earth, 
 
of Mineralogy. 371 
 
 Earth; fo as when drawn out again to bring back 
 Samples of the Earth, or mineral Matter, from 
 the Depth to which the Iron defcended; much 
 after the Manner that Samples of Sugar are taken 
 out of the Hogfhead by the Inftrument called 
 a Refi. 
 
 14. After a Mine is found, the next Thing to When 
 be confidered is, whether it may be dug to 
 vantage. In order to determine this, we 
 
 duly to weigh the Nature of the Place, and its^^^^. 
 Situation, as to Wood, Water, Carriage, Heal- 
 thinefs, and the like ; and compare the Refult 
 with the Richnefs of the Ore, the Charge of Dig- 
 ging, Stamping, Wafliing, and Smelting. This 
 is a Matter of common, civil, or ceconomical 
 Prudence. . 
 
 1 5. Particularly the Form and Situation of the 
 Spot Ihould be well confidered. A Mine muft 
 happen either (i) in a Mountain, (2) in a Hill, 
 
 (3) in a Valley, or (^) in a Flat. But Mountains 
 and Hills are dug with much the greateft Eafe 
 and Convenience *, chiefly becaufe the Drains and 
 Burrows., as the Miners call them, that is, the 
 Adits., or Avenues., may be therein readily cut, fo as 
 both to drain off the Water, and to form Gang- 
 ways for bringing out the Load, or Ore, Cfc. 
 
 1 6. In all rhefe four Cafes *, we are to look out Mines, 
 for the Veins, which the Rains or other Acci- 
 dents may have laid bare-, and if fuch a Vein/'^ opened. 
 be found, it may often be proper to open the 
 Mine in that Place, efpecially if the Vein proves 
 tolerably large and rich : Otherwife the moll 
 commodious Place, for Situation, is to be chofen 
 for the Purpofe; viz. neither on a Flat, nor on 
 the Top of a Mountain, but on its Sides : For 
 the Mineralifl: is always to exercife his Judgment 
 
 See 
 
 B b 2 
 
 m 
 
372 Lecture the Seventeenth. 
 
 in the due Choice of a Place to begin the 
 Work. 
 
 *The heft 17. The bell Situation for a Mine is a moun- 
 Situation tainous, woody, wholefome Spot, of a fafc, eafy 
 Afcent, and bordering upon a navigable River. 
 Such a Place therefore being the Standard of 
 Goodnefs, all others may be judged of as they 
 approach to, or recede from it. 
 
 J^eguires 1 8. Wood is indifpenfably necefTary for make- 
 Wood. ,-}^£ neceflary Inflruments, Engines, and 
 
 H uts ; as alfo lor fencing the Pits, or Avenues, 
 and fupporting the Rock, where large Caverns 
 are made by digging away the Ore : And 
 again, for fupplying Fewel to the melting 
 Works ; unlefs where Pit Coal will ferve the 
 turn. But though no Wood or Coal fhould 
 grow upon the Spot, it may often be fupplied by 
 iVieans of a navigable River, or cheap Carriage. 
 And thus there are fome rich Mines, in the 
 hotter Climates, Vv^ithout fo much as a Shrub 
 growing near them. 
 
 Water. 19* Plenty of Water fhould never be want- ' 
 ing, and is beft: fupplied by a River, from which 
 it may be commodioully derived, by Pipes, into 
 the Lavaderos, Smelting-PIuts, Cfr. or even 
 brought into the Burrows themfelves, and made 
 to work the fubterraneous Machines. Thefe are 
 Conveniencies not to be expedled from cafual 
 Rains, or the Torrents of the Mountains. 
 
 20. The Roads and Conveniencies of Carri- 
 
 Roads, to and from the adjacent Parts, muft be 
 
 likewife regarded ; as well for the Sale of the 
 Metal produced, as the Conveyance of Goods 
 and the Neceffaries of Life to the V^orkmen : 
 For it rarely happens that Provifions are afforded 
 by the Spot v;here Metals are found. 
 
 21. The Places abounding with Mines are 
 generally healthy } as ftanding high, and every 
 
 way 
 
Of Mineralogy. 373 
 
 Way expofed to the Air : Yet fome Places And n^hoi. 
 IVlines are found prove poifonous, and can hyjome Air. 
 no means be dug, though ever fo rich. The 
 Way of examining a lufpeded Place of this 
 Kind is, to make Experiments upon Brutes, by 
 expohng them to the Effluvia or Exhalations, 
 in order to find the Effedts thereof. 
 
 22. But a confiderable Advantage may fome- Petals oh^ 
 times be made, without the Labour and Expencc 
 
 of Digging : For as Springs and Rivulets are 
 frequently the Outlets of Mines, it may happen 
 that the Sand of fuch Waters fhall be worth the 
 waffling for Metal ; in which Manner large 
 Qiiantities of Gold-Duft are often procured. 
 
 And hence it appears to be, that the Sands of 
 many rapid Rivers, and even the Sands of the 
 Sea in fome Places, contain Gold ; though the 
 latter in fo fmall a Proportion as feldom to be 
 worth the Waffling. But the Sand of fuch Ri- 
 vers wherein llamped Ores are continually waffl- 
 ed may frequently deferve to be aflayed. 
 
 23, The Veins of a Mine differ greatly fvom^he diffe- 
 each other, in Depth, Length, and Breadth, ^ent Veins. 
 Some ftretch obliquely from the Surface towards 
 
 the central Parts of the Earth ; and thefe are 
 called deep Veins : Others lie fflallow and circu- 
 lar, fo as to encompafs a large Space ; thefe are 
 termed fpreading Veins : Others poffefs a great 
 deal of Space, both in Length and Breadth • 
 and thefe are called accumulated Veins ; being no 
 more than a Space poffeffed by a Group of Foffils 
 of one certain Kind. But to give the Hiftory 
 of Veins, and Fibres, which are fmaller Veins, 
 their Differences, their Directions, their Inter- 
 fedions, their different Goodnefs, their Difcon- 
 tinuations, their Rifing, Falling, ^c. would be 
 a large Work. Let it, however, be obferved, 
 that thefe Things feem to proceed in a certain 
 
 B b 3 order, 
 
374 
 
 Ha^ to he 
 traced. 
 
 And dug. 
 
 *The Bur- 
 ro'-ivs, ho w 
 made. 
 
 The Di T- 
 gins <va- 
 rtou!. 
 
 By the 
 Spade, 
 
 Lecture the Seventeenth.' 
 
 order, though the Laws thereof have not been 
 fo well obferved as to afford us fure Rules of 
 Praiflice : Whence It fometimes happens, that 
 after a Vein has been fuccefsfully traced for 
 fome time, it dips, breaks off, or takes a different 
 Courfe, leaving the Workmen as it were at 
 Fault. 
 
 24* When a Vein of Ore is found, and all 
 Things prepared for the Work, if the Vein be 
 of the deep Kind * it is firft to be laid bare, and 
 a Pit to be funk upon it ; at the Mouth whereof 
 a Shed is to be raifed, and a Crane, or Barrel 
 and Winch, fixed, for drawing up the Ore. The 
 Pit is to be funk either perpendicular or oblique, 
 according as the Vein happens to run. 
 
 25. it is alfo ufual, in this Cafe, to cut a Bur- 
 row, or Adit into the Side of the Hill. This 
 Burrow is iifually cut twice as high as wide, 
 that the Workmen may commodiouQy pafs along 
 it with their Barrows and Burdens ; being for 
 that Purpofe ufually about feven Foot and a 
 half high, and almofl four Foot wide. If this 
 Side Pit reaches to the funk Pit, it becomes a 
 true Burrow, open at both Ends ; and thus ren- 
 ders the Work more Ecile and commodious, as 
 the Ore may be now wheeled out in Barrows, 
 inflead of being craned up to the upper mouth 
 of the Pit. After the fame Manner it is ufual to 
 dig many Caverns into the Sides of the Moun- 
 tain, in order to fcoop out the Ore : So that 
 fometimes there are thus feveral Burrows made, 
 to the Eafe and Advantage of the V/ork. 
 
 26. The Art of Digging the Veins varies 
 according to the Nature of the Vein, or accord- 
 ing as it is foft or hard. The foft Vein is gene- 
 rally dug with the Spade, and turned out into 
 
 * See above, §.23. 
 
 wooden 
 
of Mineralogy. 
 
 375 
 
 wooden Trays, placed underneath to receive it : 
 
 But the hard Veins are knocked out with a By the 
 Gad, or Kind of Chizzd, and Hanimer. But 
 if the Ore is fo hard as to be incapable of break- 
 ing in this Manner, they ufually foften it vdth Bire, 
 Fire; which has the Power of rendering thcx 
 hardeft and moll flinty Stones brittle and friable. 
 
 But a Hill more expeditious Method is the work- 
 ing with Gunpowder; by Means whereof much-^^^*^* 
 of the hardeft Rock may be fhivered and fplit 
 in a very little Time ; a fmall Parcel of Powder 
 being laid in a long Hollow cut for the Purpofe, 
 after the Nature of a Gun-Barrel, and fired as it 
 were at a Touch-hole; a fmall Vent, where the 
 Quick- match is applied, being left for the Pur- 
 pofe, and the reft of the Orifice being hard 
 flopped up with Clay. 
 
 27. The Manner of purfuing and digging all TheDeJign 
 Sorts of Veins, the Ways of under-propping, and 
 difcharging the Water from the Vv orks, the 
 finking of Air-fliafts, curing of Damps, and^ 
 the like, we have no time to defcribe * ; our 
 more immediate Bufinefs being the Treatment of 
 the Ore, after it is dug and brought to open 
 Day. For this Purpofe there are certain pre- 
 vious Operations required, of which we propofe 
 to exhibit Examples. Our firjt Experiment, 
 therefore, will fhew the Method of Roafting 
 fulphureous or arfenical Ores ; the fecond will 
 fliew the Method of Stamping and Wafhing of 
 Ores; and the thirds the Method of preparing 
 Fluxes. 
 
 * See Agricola de re metallica. 
 
 B b 4 
 
 Ejc PE R I- 
 
37^ Lecture the Seventeenth. 
 
 yiun/itc 
 
 ronjied. 
 
 The Expe- 
 riment ex- 
 p'.ained. 
 
 And appli- 
 ed, fo the 
 kindly 
 Ores. 
 
 Experiment L 
 
 The Method of Roafting Ores. 
 
 28. We took a Pound of the common Corni(h 
 Mundic, and breaking it into fmall Lumps, ex- 
 pofed it upon the Grate of a Furnace, whilft the 
 Fire was made below •, and thus at firfi: we gently- 
 heated and torriiied the Mundic, but afterwards 
 by Degrees increafed the Fire, fo as to make 
 the Lumps glow, or appear red hot ; in which 
 State wc kepi them for half an Hour, or till no 
 more fulphureous Vapour or Stench rofe from 
 them. 
 
 29. This Experiment fhews the common Me- 
 thod of Roading Ores, in order to difcharge 
 their fulphureous, arfenical, or antimonial Farts, 
 that might otherwife hinder their Fufion, or 
 elfe carry off a confiderable Proportion of the 
 truly metallic Matter in melting. For fear this 
 metallic Matter Ihould fly off', we made the 
 Fire gentle at firfi ; but increafed it, by Degrees, 
 till the Lumps became red hot, becaufe other- 
 wife the Sulphur would not quit its hold ; for 
 Sulphur requires a naked Fire and the Afiiflance 
 of the open Air, before it will burn, or go enti- 
 rely off *. 
 
 30. The richer and more tradlable Ores have 
 no Occafion to undergo this previous Operation 
 of Roafting, but are ufually committed to Fu- 
 fion foon after being dug up, and feparated from 
 their Slone, or Mine. However, if they con- 
 tain any confiderable Qiiantity of Sulphur, or 
 Arfenic, it is ufual to roafl: even thefe a little. 
 
 See I4S8. M.pnJJlm. 
 
 31. But 
 
Of Mineralogy. 377 
 
 31. But feme Copper Ores are fo ftubborn 
 and refradiory, or hold their Sulphur fo tena- 
 cioufly, as to require many Roaffings before they 
 will let it go : being either ftamped or melted 
 after every Operation, fo that all the Parts may, 
 at feveral Times, be equally expofed to the Fire, 
 and have their Sulphur difciiarged. 
 
 32. In the large Way of Bufinefs this Opera- imj^eiar e 
 tion is ufually performed in a Trench cut fome- Way, 
 what aflope in the Ground, that the Air may 
 
 have the freer Accefs at the Bottom : they firlt 
 place a Layer of Billet- Wood in this Trench, 
 and upon that a Layer of the Ore, in little 
 Lumps, and fo continue, interpofing a Layer of 
 Wood and a Layer of Ore, for three or four 
 Stories ; when the Pile being compleated, they 
 fet Fire thereto, and make it continue to burn 
 flowly for feveral Days together, during which 
 Time there rifes a large Quantity of fulphureous 
 Vapour, that may be perceived to a confiderablc 
 Dilcance. 
 
 33. But when the Ore, by repeated Roafting, 
 Stamping, and Fufing, is become tolerably pure, 
 they now finilh the Operation by throwing it in- 
 to a particular Furnace, having a Funnel to in- 
 creafe the Draught ; fo as to make the Fire the 
 ftronger, and difeharge the fulphureous Fumes 
 in greater Plenty. And this Furnace is fo con- 
 trived, that the open Flame of the Wood may 
 play diredlly upon the Ore ; whence all its vola- 
 tile Part is feparated, and the Remainder left fit 
 for the lad Stamping and Wafliing. 
 
 34. When the Ores contain a large Qii anti ty 7 / 5 ^ W- 
 of Sulphur, this ufually fweats out and runs down/*^^«^, 
 into Cavities made on Purpofe to receive it ; 
 whence it may be ladled out, and cad into 
 Moulds. But perhaps the mod frugal Method 
 
 of reading Ores, fo as to fave, or colled, all 
 
 the 
 
378 Lecture the Seventeenth. 
 
 the Sulphur, or Arfenic, they contain, is not 
 generally known and pracftiied : For in the com- 
 mon Way, a large Proportion is loft, which 
 might be colledted by Means of a proper Hood, 
 in the Form of Flowers •, and aifo the rifing Fume 
 mig'i-, by a particular Strutflure of the Furnace, 
 be made to pafs into a large VelTel of cold Wa- 
 ter, and there be condenfed •, as we fee in cer- 
 tain chemical Diflillations and Sublimations. 
 Vitriol oh- 35. After the j)oorer and more ftubborn Sorts 
 tainahlein of Copper Ore have been thus fucceffively roaft- 
 thc come to be quenched in Water, or 
 
 wafhed, they olten impregnate the Water with 
 a vitriolic Matter ; lo that fometimes profit may 
 be made by evaporating thefe Waters, and fuf- 
 fering the Vitriol to fhoot : For the acid Part of 
 the Sulphur, here feparated by the F'ire, is 
 greatly difpofed to enter the metallic Part of 
 the Ore, and diffolve it ; fo as to form an adual 
 blue Vitriol, or Vitriol of Copper, which fells 
 for a confiderable Price. 
 
 Roapring 36. And here it fliould be remembered, that 
 generally Ores rarely yield the lefs Metal for Roaiting ; 
 pojitable. Fire were made too ftrong, efpecially 
 
 at the firfl: : For when the Yield proves fmall, 
 the general comsplaint of the Smelters is, That 
 the Ore, when fent to their Furnace, was too 
 little roalfed ; though indeed the fault is often 
 their own, in neglecting to make their Fire fufn- 
 ciencly brifle and ftrong from the firft ; which is 
 a very confiderable Secret for increafing the 
 Yield of an Ore. 
 
 W not 3 *^- There are, however, fome Reafons to be- 
 ai^ayi in lieve, that many imperfe6t Ores lofe confidera- 
 imperfea gjy of their Metal by Roafting, efpecially when 
 they are mixed with arfenical, or antimonial. 
 Matters, which have a known Property of vola- 
 tilizing the impurer Metals, and carrying them 
 
 Qir 
 
f 
 
 Of Mineralogy: 379 
 
 [ off in Fume : Whence, doubtlefs, it is that 
 il fome poor Ores and Mundics are commonly 
 treated with little Succefs. 
 
 38. The Remedy in this Cafe we apprehend Thishcon- 
 to be the due Ufe and Application of fome fixing sentence 
 Suhftances^ whether of an abforbent, alkaline, or 
 I neutral Nature *, fuch as Qiiicklime, Kelp, or 
 Pot-Afli, dry River-Mud, Clay, Iron-Filings, 
 or the like, mixed or ftratihed along with the 
 Ore. And by certain Additions of this Kind, 
 v/e doubt not but the Yield of fome poorer Ores 
 might be confiderably increafed. 
 
 39. The Bufmefs of Roafting Ores may RoajUng 
 be improved, and reduced to a few eafy Rules, reduced to 
 (i) We fee it is of two Kinds, or fimple and 
 compound *, that is, either with or without Ad- ^^dditloni, 
 dition. No Addition is wanted when the Ore 
 proves rich, or in itfelf nearly of a metallic Na- 
 ture, as fome Ores are found to be. But Addi- 
 tions are principally required, when arlenical, 
 antimonial, or fulphureous Matters are natural- 
 ly mixed wdth the Ores 
 
 40. (2) The Fire is to be fo regulated, from fheFire^ 
 the firfb, that only the lighter, or more volatile, 
 fulphureous, or arfenical Fumes may go off; 
 otherwife the more metallic Part alfo would fly 
 away, and, without fome proper Contrivance to 
 catch it, be loft. Yet the Ore mult feel the 
 
 force of an open Flame at iaft*, otherwife all the 
 Sulphur, Arfenic, Antimony, and other imma- 
 ture mineral Subfliances, will not be diflodged. 
 
 41. (3) The more thefe immature Subftances 
 abound in the Ore, the gentler the Fire fliould 
 be at firfl: •, and when the greater Part of them 
 is thus exhaled, the Fire is to be quickened by 
 a freer Admifllon of the external Air. 
 
 See §. 38. 
 
 42- (4) 
 
380 
 
 AndWaJk- 
 ing. 
 
 Mundic 
 Jlamped 
 and nx:ap‘ 
 ed. 
 
 TVafrAng 
 andStafnp- 
 ing not al' 
 ejoayi ne- 
 cejjdry. 
 
 Hard 
 Ores, hovi 
 foftened 
 
 Lecture the Seventeenth. 
 
 42. (4) Laft]y ; Where fuch fixing Additions 
 are ufed as are not metalJinc, for Example, Lime, 
 Mud, the unrnetallick Parts ought again 
 to be feparated by Stamping and Walhing, be- 
 fore Fufion, which would other v/ife be hin- 
 dered, or ufelefsly encumbered. 
 
 Experiment II. 
 
 "The Method of Stamping and IVafmng of Ores, 
 
 43. We took the Mundic roafted in our for- 
 mer Experiment, beat it fine in a metalline 
 Mortar, and learced it ; then putting it into a 
 Buddling-Difh, we wafhed it in feveral Waters, 
 taking care to feparate the heavier Portion from 
 the lighter, and drying this heavier Part, which 
 is always the more metallic. 
 
 44. Thefe Operations of Stam.ping and Waffl- 
 ing are not necefTary in the richer Sorts of Ores, 
 but are often abfolutely required in the poorer 
 and more flinty Kinds. If a large Quantity of 
 mere flony Matter adheres to the Ore, it is fome- 
 times knocked off with Elammers ; fo as to leave 
 the more metallic Part free from this barren or 
 fuperfluous Subflance. 
 
 45. If the Ore ffill proves hard and flinty, 
 it is fometimes foltened by lying, for feveral 
 months, expofed to the open Air, which thus 
 renders it fle for the Stampers ; though it fome- 
 times alfo requires to be heated, or ignited, and 
 quenched in Water, to fit it for that Purpofe. 
 Thus a large Heap of hard, and otherwife un- 
 tracfable. Ore mav be heated red hot, by inter- 
 fperflng it with Billets, and letting them on 
 fire ; after which it may readily be quenched, 
 and rendered friable, by throwing cold Water 
 upon it, or by paiTing a fmall Stream of 
 Water through it, derived from fome adja- 
 cent River. And fometimes this Operation 
 
 mufl 
 
Of Mineralogy. 381 
 
 muft be repeated, before the Ore will grow foft 
 and tracStable. 
 
 46. It is ufnal to ftamp moft Ores in a State Oresho-M 
 of Moiiture or Wetnefs, to prevent the Avola- befi jiamp- 
 don of their Dull or Powder; but efpeciaily 
 
 fuch as require much wafhing to feparate their 
 barren and lighter earthy Parts, which would 
 otherwife ufelefsly encumber the melting Fur- 
 nace. To perform this Stamping the more com- 
 modioufly, a Stream of Water is made to pafs 
 under the Stampers ; fo as to make various win- 
 dings and turnings, and, in Part, run into cer- 
 tain Cavities, made on Purpofe to catch and 
 detain the heavier Matter, whilft the lighter 
 is wafhed away to a greater Diftance by the 
 Current. 
 
 47. But the Method of wafhing the Ores of 
 
 the nobler Metals is more exad and curious ; j 
 
 as in wafhing of Sand for Gold, on the Banks 
 of the Rhine and Danube^ where Gold is fre- ed. 
 quently found, efpecially in fuch Places where 
 the Sand is raifcd into large Heaps, or a Kind 
 of Mountains, by the Rapidity of the Stream. 
 
 48. Thefe Sands are ufually wafhedby the Pland, 
 in a long Trough, made for the Purpofe, with a De- 
 fcentorCurrent,and linedattheBottornwithFlan- ^ * 
 nel ; for thus the Sand being artificially agitated 
 
 with the Hand, the lighter and larger ftony Matter 
 rifes uppermoft, v/hilfl the heavier defcends, and is 
 catched in the Pores of the woolly Cloth at the Bot- 
 tom; in the mean Time the lighter Matters are 
 wafhed farther off* by a Stream running down the 
 Declivity. V\/^hen the Flannel has thus collecfled 
 a confiderable Quantity of the richer metallic 
 Matter, the whole Cloth may be eafily taken off, 
 and rinfed in a proper VelTel of V/ater, where 
 
 all 
 
382 Lecture the Seventeenth. 
 
 ' all the metallic Matter, before adhering to it, 
 readily falls off, and finks to the Bottom of the 
 Veffel ; and then, the Water being decanted, 
 the Metal may be colledled alone and dried. And 
 this is the Method of procuring the Gold where 
 the Sand is fine, or extremely fmall. 
 fhecoarfer larger Works, or where the Gold is 
 
 mixed with big Sand, Gravel, or Stones, they 
 make Ufe of Wire-Sieves, whofe Meafh is always 
 of one certain Size ; fo as readily to tranfad’ the 
 fine Sand, or Gold Duff, and retain the larger 
 Gravel and Stones behind : For it is extremely 
 rare to meet with a Grain of Gold, in the Sands 
 of Rivers, fo large as a Barley-Corn. Whence 
 this Method by the Sieve is highly ferviceable, 
 and conducive to the former Operation : For 
 though a large Quantity of fine Sand thus paffes 
 the Sieve, it may be readily feparated in the 
 Trough, after the Vethod already defcribed 
 •The End of 50. And this may fulfice to fhew the general 
 Stamping particular Methods of Stamping and Wafh- 
 anJ.WaJh- Qres. We fee the End of thefe two pre- 
 vious Operations is to get rid of the Matters 
 which are not metalline ; that fo the Furnace may 
 not be ufelefsly employed upon fuch Subftances 
 as will themfelves yield no Metal in the Fire, 
 and only hinder the metallic Parts of the Ore 
 from coming together, and affording a Yield 
 anfwerable to the Expence and Trouble of the 
 Fufion. 
 
 * § 4 ^- 
 
 Experi 
 
Of Mineralogy. 
 
 383 
 
 Experiment III. 
 
 Ways of preparing the ftrongeft Fluxes. 
 
 51. We took four Ounces of red Lead, an GJa/s of 
 Ounce of White Sand in Powder, and ^ead pre^ 
 Ounces of dry decrepitated Salt, and mixed 
 
 them all well together in a Mortar ; this Mix- 
 ture we put in a clean Hejfian Crucible, fitt- 
 ed with a Cover, and fufed it in a Wind-Fur- 
 nace for a Quarter of an Hour ; then taking it 
 out, and letting it cool, we broke the Crucible, 
 and found the Salt at top, and a pure Glafs of 
 Lead at the Bottom : This Glafs we carefully 
 feparated and kept apart, as a powerful Flux. 
 
 52. The Salt is of no other Ufe in this Ope- 
 ration, than to ferve as a Flux to the Sand, and Kfed there- 
 make it m.ore readily unite with the Red Lead \ 
 
 fo as to form a Glafs without any great Violence 
 of Fire, or the Necefiity of detaining it long 
 therein. So that by this Means a Glafs of Lead 
 may be readily prepared for the Purpofe of arti- 
 ficial Gems or other Ufes. 
 
 53. This Glafs of Lead is an extremely ufeful of 
 
 Flux in the Bufmefs of afTaying-, and when kept^^^^^ Glafs. 
 long in Fufion, pafies through the Pores of any 
 common Crucible, almofi: like Water through 
 
 a Sieves fo as, upon the Teft, readily to vitri- 
 fy, and carry off, all Sorts of metalline and mi- 
 neral Matters, except Gold and Silver : On 
 which Property, therefore, the Art of Cupelling 
 depends. 
 
 54. Fluxes feem reducible to two general fluxes of 
 Kinds', the vitreous and the faline. By the t-^oKinds\ 
 
 * See L.:?. XIV. Exp.ll. andV. 
 
 vitreous 
 
384 Lecture the Sev nteenth. 
 
 viz. the 
 ’Vitreous, 
 
 and fallne. 
 
 vitreous we underftand all thofe which either 
 have of themfelves, or readily alfume, a glalfy 
 Form in the Fire *, among the Principal whereof 
 we reckon the Glafs of Lead, the Glafs of Anti- 
 mony, and Borax. 
 
 ^Iheir dif- 
 ferent 
 'Ufes. 
 
 Some Ores 
 require no 
 flux. 
 
 Metallurgy 
 
 impronje- 
 
 able by df- 
 
 co^uering 
 
 cheap 
 
 fluxes. 
 
 55. By the f aline Kind of Fluxes we under- 
 fland all thofe that are compofed of Salts, whe- 
 ther Tartar, Nitre, fixed Alkali, or the like. 
 And among the Principal of this Kind we reckon 
 the Black Flux, which we formerly fliewed how 
 to prepare alfo Sandiver, Kelp, i£c. 
 
 56. The vitreous Kind feem more immediate- 
 ly deftined to acfi; upon the ftony or vitrefcible 
 Matter, wherewith ftubborn Ores are frequently 
 mixed ; and the faline Kind, to a6l more imme- 
 diately upon the Ore itfelf, for the due Exclu- 
 fion or Separation of the Metal. 
 
 57. The more kindly Ores require no Flux to 
 make them run thin, or to afford all the Metal 
 they contain. And fometimes Ores are fo kind- 
 ly as to contain their own Fluxes within theni- 
 felves. Thus we have met with Copper-Ores, 
 which being barely ground to Powder, and 
 melted, without any Addition, in a comimon 
 Wind Furnace, have yielded as much, or even 
 more pure Metal at the firft Operation, than 
 we could obtain from them by Means of the 
 ufual Fluxes. Whence we fee that artificial 
 Fluxes are not always neceifary ; or that the 
 principal Ufe of them is for the ftubborn or lefs 
 tradtable Ores. And thefe are fometimes fo 
 exceedingly hard to fufe, and bring to a metalline 
 Form, that it requires the utmofi: Power of Arc 
 to treat them advantageoufly in the larger Way 
 of Bufinefs, vdiere no confiderable Expence can 
 ufually be allowed for Fluxes. 
 
 » S-e Lea, I. Exp, II. 
 
 58. On 
 
Of Mineralogy. 
 
 385 
 
 58. On this account it is that many Mines re- Metal- 
 main unwrought, as being intractable without 
 great Charges. Whence the Improvement of the 
 Bufinefs of Fluxes, fo as to render them cheap 
 
 and efFeclual, might greatly contribute to the Im- 
 provement of Metallurgy. We would therefore 
 recommend to farther Enquiry what Matter it is, 
 in the more foft and tradfable Ores, which renders 
 them fo fufible, and eafy to part from their 
 Metal. Certain Experiments which we have made 
 with this View feem to fhew, that in Copper-Ores 
 it is a Kind of bituminous Subftance, capable of 
 melting, by a Itrong Heat, into a foft and black 
 kind of Glafs. 
 
 59. Some of the mod powerful and cheap The cheap 
 limple Fluxes hitherto known are dried Wine- 
 
 Lees, dried Cow-dung and Hone- dung, dried 
 River-Mud, Fuller’s Earth, Iron Filings, com- 
 mon Salt, Glafs, Kelp, Pot-Afh, Sandivcr, Cfr. 
 which may be ufed in the larger Work *, as N ere, 
 
 Tartar, Borax, Sal-Ammoniac, Mercury-Subli- 
 mate, Cfr. may in the fmalier, or for the making 
 of Afiays. 
 
 60. As for compound Fluxes, they are nume- Cheap' 
 rous ; almod every Operator having his favou- compound 
 rite one. And certainly Ibme Fluxes are better Maxes, 
 adapted than others to certain Ores. But per- 
 haps a few general ones might be fixed upon, 
 which fhould ferve inflead of ail thofe hitherto 
 commonly known and uled. We will here re- 
 commend three, which are powerlul, almofl; ge- 
 neral, and not exj)enfive. 
 
 61. (i) Take of Nitre, prepared by long boil- 
 ing it in Lime-Water, of Sea-Salt melted in the 
 Fire, Sandiver, and dry Wine-L.ees, each one 
 part ; Glafs of Lead, three Parts ; and powdered 
 Glafs, eight parts : mix them all well together. 
 
 C c This 
 
386 
 
 Lecture the Seventeenth. 
 
 This Flux added, in an equal Weight, will fufe 
 a very ftubborn Ore. 
 
 62. (2) For a (till ftronger, take equal Parts 
 of white Tartar, common Salt, and Nitre, pre- 
 pared as above i calcine them to a white Pow- 
 der, and mix therewith its own Weight of Glafs 
 of Lead *, and of this Flux add two Parts to one 
 of the ftubborneft Ore. 
 
 ^3 (3) For a powerful faline Flux take of 
 the ftrongeft Soapboiler’s Lees four Pounds, white 
 Tartar and common Salt, melted in the Fire, 
 each one Pound *, boil them together with five 
 Gallons of human Urine, to a dry Salt. This 
 Flux is particularly proper where Sulphur and 
 Cobalt abound, and render the Ore very refradtory. 
 
 Jm- 5^^ But the great Secret in the making and 
 ^ofTluxe! Fluxes, is not only to feparate the 
 
 of ^jj-eady ripened in the Ore, but even to 
 
 mature and ripen the crude or immature Part of 
 the Ore in the Fire. Something of this Kind, 
 we apprehend, may be effedled ; as having rea- 
 - fon to believe, that certain Fluxes, will obtain a 
 larger Yield of Metal from certain Ores, than 
 other Fluxes in common Ufe, though efteemed of 
 the beft, and though they are perhaps of the dear- 
 eft Kind. Thus clean Iron Filings will often do 
 more than Borax. But as the Scales and Crocus, 
 or Ruft, of Iron have been commonly ufed, in- 
 ftead of pure and perfedt Iron itfelf, for a Flux, 
 few Operators appear acquainted with the Excel- 
 lence of perfedt Iron employed for this Purpofe. 
 Many Advantages alfo are now commonly reaped 
 by a prudent Mixing of one Ore with another of 
 the fame Denomination, and with the Slags of 
 Recrements of Metals, in the Way of a Flux. 
 
 AXIOMS 
 
Of Mineralogy. 
 
 3^7 
 
 Axioms and Canons* 
 
 1. We learn from the preceding Enquiry, that 
 to pradtife Mineralogy and Metallurgy to advan- 
 tage, a confiderable Knowledge in Natural Phi- 
 lofophy and the Operations of Chemiftry is re- 
 quired 
 
 2. That many Mifcarriages in mineral Attempts 
 have been owing to the Want of a competent 
 Skill in Mechanics, Hydraulics, and Chemiftry a 
 
 3. That the Profit attending the fcientifical 
 Working of Mines is generally greater^ and up- 
 on the whole more confiderable, than that of 
 Agriculture, or Merchandize h). 
 
 4. That there are two Ways of difcovering 
 Mines ; viz, by Accident, and by Art : The 
 latter whereof belongs to the intelligent Mine- 
 ralift c), 
 
 5. Tliat the Art of difcovering Mines depends 
 upon a certain Sagacity, which may be acquired 
 by Ufe and Pradlice •, or upon the Obfervation of 
 particular Signs that generally denote a Mine 5 
 and again upon the Method of Boring, according 
 to fome Analogy of Knowledge, gained by being 
 converfant with the common Appearances, Situa- 
 tions, and other Phaenomena of Mines c). 
 
 6 . That the Art of difcovering Mines is redu- 
 cible to Rule, fo as not to be mere Conjedture, 
 or Guefs-work c), 
 
 7. That in general, Mines are to be firft 
 opened where a Vein is laid bare by accident or 
 otherwke, efpecially if it prove large or rich : 
 But where no fudi Encouragement appears, the 
 
 nj §4—6. and Exp. I. II. III. 
 
 i ) § 4—6. 
 
 ^ g .13. 
 
 C c 2 
 
 Tides 
 
388 Lecture the Seventeenth, 
 
 fides of Hills are preferably to be chofeii for an 
 opening a). 
 
 8, That a deliberate Confideration, and a com- 
 petency of oeconomical Prudence, are ufually 
 required to determine before-hand, whether a 
 M ine, after it is difcovered, may be wrought to 
 Profit h ). 
 
 9. That the moft perfect Situation of a Mine 
 is to be mountainous, woody, eafy of Afcent, 
 healthy, bordering upon a navigable River, and 
 good Roads b). 
 
 19. That Metals may be fometimes obtained 
 to Advantage without Digging *, or barely by 
 wafhing the Sands of certain Springs and Ri- 
 vers c'). 
 
 11. That mineral Veins differ greatly from 
 each other, and accordingly require different 
 Methods of Digging, which may be reduced to 
 flandard Rules of Pradfice d). 
 
 12. That the Bufinefs of Mining is improve- 
 able by difcovering' better Methods of preventing 
 or curing Damps in Mines, rendering poifonous 
 Mines wholefome, or defending the Bodies of 
 the Workmen againft their ill Efedts ; as alfo by 
 difcovering better Methods ofraifingor dilcharg- 
 ing the Waters, following the Veins, breaking the 
 Rock, bringing up the Ore, d), 
 
 13. That the End of Roafting Ores is to dif- 
 charge their fulphureous, arfenical, antimonial, 
 or other rapacious Matters ; which would other- 
 wife carry off the purer Metal in the melting Fur- 
 nace, and defraud the Account e). 
 
 14 That the richer Ores require neither Roaff- 
 ing, Stamping, nor Wafhing ; but may be dl- 
 
 a ) § 14-- 16. h ) § 14- — 21. c ) § 22, 47—49. 
 
 J ) S 23 26. e ) Exp. I. 
 
 redtly 
 
of Mineralogy. 
 
 redlly committed to the Smelting-Furnace, without 
 FI l:x or Addition a), 
 
 15. That in order to roaft Ores in Perfedlion 
 per the Fire fhould be gentle at firft, and 
 afterwards inc eafed to a Degree of ignition in 
 the Ore b). 
 
 16. That fome Ores, joined with rapacious 
 mineral Matters, may be advantageoufly mixed, 
 or ftratified, in Roafting, with proper fixing In- 
 gredients b). 
 
 17 That O es are fddom rendered the poor- 
 er, but generally the richer, for Roifting ; un- 
 lefsthe Fire at be made too ftrong b), 
 
 18. That the Bufinefs of Roafling Ores is im- 
 proveable, and reducible to a few eafy Rules, 
 with a View to render the Ore more pulverable, 
 and difcharge its volatile, fulphureous, and ar- 
 fenical Parts ; which, if retained, would, in 
 ftrong Fufion, partly prevent the Separation of 
 the purer Metal, and partly carry it off into the 
 Air b). 
 
 19. That Metals, in their Ores are not thofe 
 fixed Bodies they appear to be in the Bars or In- 
 gots, into which they are brought by metallurgi- 
 cal Operations a). 
 
 20. That the Operations of Stamping and 
 Wafhing are required only in the hard, flinty, 
 and poorer Ores ; the Defign of thefe Operations 
 being merely to feparate the ufelefs terreftrial, or 
 flinty and ftony Parts, which would otherwife 
 encumber the Furnace and leffen the Yield. 
 
 21. That fome hard Ores, may be foftened, 
 or rendered fitter for Stamping and Wafhing, 
 barely by lying expofed to the open Air, which 
 feems to turn fome Parts of the Ore into a faline 
 
 a) Exp. I.ILIir. 
 
 C c 3 Matter 
 
Lecture the Seventeenth, 
 
 matter, or Vitriol ; whence a Kind of Friability 
 or Softnefs is communicated to the Reft a). 
 
 2 2. That the hardeft or ftubborneft Ores may 
 be foftened, and rendered fitter for the Stampers, 
 by being firft ignited, and then quenched in Wa- 
 ter*, efpecially if this Operauipn be feveral Time§ 
 repeated ^ ). 
 
 23 That the two Operations of Scamping and 
 Wafhing are, in good Meafure, reducible to one, 
 in the ordinary Ores; the Courfe of the Water 
 being fo directed under the Stampers, as imme- 
 diately to carry off the lighter ftony Matters, 
 and leave the heavier or more metallic Part's 
 behind b). 
 
 24. That the Sands of certain Rivers may, by 
 a flight manual Operation, be fometimes wafhed 
 for their Gold to confiderable ProBt c). 
 
 25. That the wafhing of Sand for Gold may 
 be confiderably expedited, by a proper Ufe of 
 the Sieve 
 
 26. That Glafs of Lead is a powerful Flux*, fo 
 as to be capable of vitrifying, and carrying, away 
 with itfelf upon the Teft, all the metallic or mi- 
 neral Matters that are not either Gold or Silver 
 
 27. That the vitrefcible Clafs of Fluxes are 
 tnore adapted to operate upon’ the ftony Parts of 
 Ores, and the faline Clafs upon the Ores them- 
 felves, fo as to feparate their Metal d). 
 
 28. That the Bufinefs of A flaying and Refining 
 Gold and Silver, depends upon that Property 
 which Lead and the Glafs thereof have of vitri- 
 fying, and carrying off upon the Teft, all the 
 known Matters, except the two nobler Metals d). 
 
 sc ) Exp. II. See alfo Le£i\ III'. 
 
 b)Exp.lL ' 
 
 €) § 2 2 , and Exp. II. 
 
 ) Exp, 111, 
 
 29. Tha 
 
of Mineralogy. 
 
 29. That fome Ores naturally contain their 
 own Fluxes, and are therefore beft aflfayed and 
 fmelted per fe a), 
 
 30. That the Bufinefs of Metallurgy might be 
 conliderably improved, by difcovering a cheap and 
 general Set of powerful Fluxes a ). 
 
 3 1 That an Enquiry into the Nature of the 
 fufible Matter, naturally contained in the more 
 kindly Ores, might lead to a Difcovery of fome 
 cheap and powerful Fluxes a ), 
 
 32. That the large Number of compound 
 Fluxes might be reduced to a few general Kinds, 
 capable of performing as much as all of them 
 feverally a), 
 
 33. That the greatefl: Improvement of Fluxes 
 depends upon making and ufing them fo as to ma- 
 turate the Ore, or otherwife caufe a larger Yield 
 than can be procured by the common Fluxes a), 
 
 34. That fuch maturating Fluxes may be, in 
 fome Degree, obtained by a farther Knowledge 
 of the Properties, Affinities, or Relations betwixt 
 Metals and Metals, Metals and Minerals, Ores 
 and Ores, or Minerals and Minerals a). 
 
 a ) Exp, III, 
 
 C c 4 
 
 LEG- 
 
[ 392 ] 
 
 ^he Suh^ 
 je5h 
 
 Metallur- 
 gical Ope- 
 rations of 
 tnxo kinds, 
 
 Jjfaying, 
 
 And Smelt' 
 ing. 
 
 Dejign of 
 the Expe- 
 riments. 
 
 LECTURE. XVIII. 
 
 CONTAINING 
 
 Metallurgy; or' the Art oj Affaying, 
 and working Metals from their Ores, 
 
 H aving already confidered the fe- 
 veral Parts of Mineralogy as pre- 
 vious to the Art of Metallurgy., we 
 now come to Enquire into the Operations of 
 Metallurgy itfclf. 
 
 2. Thele Operations are of two kinds, or 
 fmaller and larger ; with regard to which the whole 
 of Metallurgy may be divided into two Parts ; 
 viz JJfaying^ Smelting. 
 
 3. By Airaying we underftand the Method of 
 determining by Trial, in Miniature, what will 
 be the Yield of an Ore in pure Metal when it 
 comes to be wrought in the larger Furnace. 
 
 4. And by Smelting we underdand the feveral 
 Ways of reducing Ores to pure Mrtal in the 
 large Way of Bufinefs, fo as to fit the Produce 
 for the civil, mechanical, and oeconomical Ufes. 
 
 5. We fhall here enquire into both thefe Parts 
 of Metallurgy, or confider as well the Smelting 
 as the AiTaying of Ores. Thus the firft Experi- 
 ment will fhew the Method of Aflaying and 
 Smelting Gold and Silver; fecond will fhew 
 the Method of feparating Gold from Silver ; the 
 third will fiicw the Method of Aflaying and Smelt- 
 
 » See Lea, XVII. 
 
 ing 
 
of Metallurgy. 
 
 ing' Copper, Tin, Lead, and Iron ; the fourth 
 will (hew the Method ot making Brafs and Princes 
 Metal V and the fifth will exhibit the Method of 
 making Steel. 
 
 393 
 
 Experiment I. 
 
 "The Method of ^ffaying and Smelting Gold and 
 Silver Ores, 
 
 6. (i) We took a Penny -weight of Silver- Silver Ore 
 Ore reduced to fine Powder; and having 
 
 it together with half an Ounce of Lead cleared of 
 its Silver, into a little flat Eflfay-Crucible, under 
 a Muffle, in the Tefting- Furnace, we continued 
 to Life a gentle Heat till the Lead had imbibed 
 the powdered Oie at lead its metallic Part, and 
 feparated the more ftony Matter in form of a 
 glafly Scoria at the Top. (2) We now took out 
 the Lump of Lead, impregnated with the Silver 
 of the Ore, and placed it upon a which 
 
 had been heating, or nealing, all this while un- 
 der the fame Muffle; and working with a pro- 
 per Degree of Heat, till all the Lead was either 
 evaporated, vitrified, or funk into the Tefl, we 
 found a little Bead, or Grain, of Silver left be- 
 hind ; which Grain, or Bead, being exadly weigh- 
 ed, and compared with the original Weight of 
 the Ore, gives the proportion of Silver contained 
 in the Ore, that is, determines its Richnefs : And 
 the fame Method is equally applicable to Gold- 
 Ores, Sand, or any other Matters containing 
 Gold, Silver, or a Mixture of both. 
 
 7. This Operation is ufually called Tefting, 
 
 or Cupelling; and exhibits almoft the whole Kxx. ratiolex- 
 of the Aflay- Mailer and Refiner. We fee the plained, 
 Procefs con fills of two Parts ; viz. Imbibition., 
 and Separation : For the Lead is firll made to 
 
 drink 
 
394 
 
 Lecture the Eighteenth. 
 
 drink in all the Silver from the Ore ; and then 
 the fame Lead is entirely feparated from the 
 Silver, And in this Manner alfo are Eflays 
 taken of Silver Coin, or any Mixtures of the no- 
 bler with the ignobler Metals : For when the 
 Operation is exadily performed, no other Me- 
 tals, bcfides Gold and Silver, will be left upon 
 the Teft. 
 
 7 /j Ratio- The phyfical Reafon of the prefen t Procefs 
 deferves to be enquired into. The Laws or Prin- 
 ciples on which it depends are thefc : (i) When 
 the imperfed' Metals, or other Minerals, are ad- 
 ded to melted Lead, fome of them will not enter 
 iifto it, but remain floating on its furface, in form 
 of a hard Scoria ; v^hich is the Cafe with Iron : 
 (2) Others enter it, but gradually emerge again-, 
 as Tin: (3) Others totally exhale; as Regulus 
 of Antimony, and Arfenic : (4) Others again 
 burn to Afhes, or run into Glafs, along with the 
 Lead ; as does Copper : But (5) neither Silver nor 
 Gold is capable of flying off, burning to Afhes, 
 or turning to Glafs, by being detained in melted 
 Lead : Whence thefe two Metals, of courfe, re- 
 main pure and feparated from all the Reft, at 
 the End of the Operation. And thus we find, 
 that the Gold and Silver remaining all the Time 
 mixed among the Lead, without going into 
 Glafs, continually fink down from the fhelving 
 fides of the Teft, towards the Bottom of the 
 Hollow, along with the Lead ; which being at 
 length totally confumed, and the Fire unable to 
 keep Silver or Gold melted without lome Addi- 
 tion of Lead, they neceffarily grow rigid, and 
 fix in a fmall Bead at. the Centre of the Teft. 
 
 Gold and 9. In the large Way of Bufinefs, Silver or Gold 
 ^iher Qrcs aic treated either by Amalgamation with 
 ^reatedln Smelting and refining them 
 
 the large Lead. The Method by Amalgamation is 
 
 Way. ufed 
 
of Metallurgy. 395 
 
 ufed only where the Ore is exceeding rich •, par- Amal- 
 ticularly at the Silver Mines of Fotofi: For 
 grinding fuch rich Ores with Mercury, the no- 
 bler Metals will be drunk up by it, and may 
 be readily feparated from it again by Diftiilation, 
 which carries over the Quickfilver, and leaves 
 the nobler Metals behind. Lead is ufed along 
 with the poorer Ores, in order to drink up the 
 nobler Metals they may contain *, which it does 
 much after the fame Manner by Fufion, as Quick- 
 filver does without it v fo as to feparate many he- 
 terogeneous Parts, by keeping them floating, and 
 afterwards reftoring the nobler Metals, by Cu- 
 pellation. 
 
 10. The large Way of Smelting Gold and^«^-^«- 
 Silver Ores is analogous to the fmall one of Af- Al- 
 laying ; all things being proportionably larger, 
 
 the Fire animated with Bellows, and the Blaft 
 direded upon the Surface of the melted Metal ; 
 fo as to blow off the Lead in the Form of Li- 
 tharge, before it is fully vitrified. But here the 
 Silver is not perfedly refined at one Operation ; 
 fome Proportion of Lead ftill remaining mixed 
 among it, that requires to be burnt our^ after the 
 fame Manner, in a ftronger Fire ; And even thus 
 it is with great Difficulty that Silver can be ob- 
 tained pure, or totally feparated, either from 
 Lead or Copper. This large Way of working 
 might perhaps be improved in refped of the Vel- 
 fel or Teft employed, and the Management of the 
 Fire fo as to work by the Means of Flame, with- 
 out the Affiftance of Bellows. 
 
 11. With regard to the Teft, we are to ob- The larger' 
 ferve that Bone-Afhes, though ever fo well waffi- 
 
 cd and fitted, are not, perhaps, the fitteft mat- 
 ter to make Tefts of-, the Tefts fo made being 
 apt to crack in the Fire, unlefs dried very gently 
 for many Days before they are ufed. But there 
 ‘ ^ ^ ^ is 
 
And the 
 Tire, 
 
 396 Lecture the Eighteenth. 
 
 is a particular Kind of Talc, or unvitrifiable 
 Spath-Stone, that being calcined to fine Pow- 
 der, as it readily may, and made up with a fmall 
 Solution of Vitriol in Water, affords fuch Tcfts 
 as m.<y be immediately ufed without Danger 
 of cracking. 
 
 12. Again; the Flame of a Wind -Furnace 
 may be rriadc to pL.y upon the Surface of the 
 melted Metal ; fo as readily to perform this 
 Operarim, without the Ufe of B^^llows which 
 violently tear away the Silver along with the 
 Lead, in the Form of Litharge. Arid this far- 
 ther Convenience may be obr ined, that not 
 only fmaller and cheaper Wood, but even Pit- 
 Coal fhall here ferve for the Fewe! ; provided 
 the Strudture of the Furnace be contrived for the 
 Purpofe. And in fome Places they have of late 
 advantageoufly ufed common Pit- Coal for Tuft- 
 ing in the large Way; and the fame Improve- 
 ments might aifo be made in the fmall Way of 
 Aflaying. 
 
 13. But how improveable foever the Bufinefs 
 
 AJfafing 
 
 imperfect. 
 
 of AflTaying may be, it is fcarce worth while 
 to intimate in what Particulars it m ght be im- 
 proved ; becaufe the Affay-M afters in all Coun- 
 tries are obhged to make their Afiuivs in the Man- 
 ner peculiar to each Country : Whence we fee 
 one Rcafon of the Difagreemerits, fo frequently 
 complained of by Merchants, in the Affays made 
 upon the fame Kinds of Ore, in Holland^ Ger- 
 many^ England^ France^ &c. The Methods em- 
 ployed for this Purpole all over Europe are, how- 
 ever, in moft Refpeds the fame ; but fhould never 
 be trufted, unlefs two or three Experiments at 
 leaft, made at the fame Time, by the fame Per- 
 fon, agree in the fame Report. ^ 
 
 14. And 
 
Of Metallurgy. 
 
 14. And perhaps in all Natural Philofophy, 
 
 • Chemiftry, and Metallurgy, there are no Experi- 
 ' ments which require greater Skill, Accuracy, and 
 Truth of Work, than thofe in the Art of Afiay- 
 ing, to make them fit to be depended upon : 
 Nor indeed can fuch Precifion as is here required 
 be well expeded, but from thofe who are ac- 
 quainted with the rapacious Nature of many 
 volatile mineral Fumes, and the Methods of fix- 
 ing them, or preventing their carrying off the 
 nobler Metals upon the Teft. To afifay in Per- 
 fedion alfo requires a Knowledge of the Rela- 
 tion and Differences of all the Metals with re- 
 gard to each other ; and particularly to Lead 
 and Antimony. As this Art therefore requires 
 fo much Knowledge, and fo much Accuracy, in 
 order to pradife it with Succefs \ hence, doubtlefs, 
 proceeds the Difficulty we find in procuring a 
 true Effay to be made upon any uncommon Ore : 
 For the Art of Affaying is extremely backward 
 in admitting of Improvements \ as if it were 
 to defeend unaltered from one Generation to 
 another. 
 
 Experiment II. 
 
 ne Method of feparating Gold from Silver^ by 
 Variation. 
 
 15. We took a mixed Mafs of Gold and Sil- 
 ver, and melt'ng it along with three or four 
 tim.es its own Weight of pure Silver, we beat the 
 whole Lump, when cold, into a thin Plate; which 
 we put into a GUIs of ^voo\ Aqua fortis fet in 
 
 warm Sand ; whereby the Silver was foon dif- 
 foived, and the Gold let fall in a black Powder 
 
 ♦ See Lea. VI. VI. 
 
 397 
 
 Its biffi. 
 culty. 
 
 Gold fepa~ 
 rated from 
 S il^er by 
 Aqua for- 
 tis. 
 
 CO 
 
398 Lecture the Eighteenth. 
 
 to the Bottom. The Solution of Silver we now 
 carefully poured off, and adding a little frcfh 
 J([ua fortis to the Gold, w^e ufed a fomewhac 
 ftrongcr Heat than before, in order to diffolve 
 any remains ot Silver from amongft the Gold' 
 Powder. Then the Aqua fortis being again de- 
 canted, we wafiied the Gold well, in feveral Par- 
 cels ot fair Water. And now the Gold- Powder 
 was put into a little Say-Cup, and placed under 
 the Muffle in the Tefting-Furnace till it became 
 yellow. It might otherwife have been melted 
 with Borax ; which brings it to its true Colour 
 and Form. We afterwards weighed the Gold, 
 to determine the Proportion it bore to the Silver. 
 Laffly, we precipitated the Silver out of the Aqua 
 fortis^ by fufpending a Copper- Plate therein § 
 then waffled the Calx, and reduced it to its me- 
 talline Form in the fame Manner. 
 
 Ratio- 16. The Reafon for adding three or four Times 
 nale. Quantity of Silver, in Proportion to the mix- 
 
 ed Mafs, is, for fear the Mafs fflould contain too 
 much Gold to be fit for the Operation *, or to 
 fpread the Gold contained in the Mafs, and dif- 
 fufe it fo thinly, that it may not defend the Silver^ 
 as it otherwife would do, from the adtion of the 
 Aqua fortis. And from the proportion of this 
 Addition it Teems to be that the Operation is 
 called Variation, 
 
 The 17* This Method of feparating Gold and Sil- 
 
 Troubie ver was unknown to the Ancients ; who there- 
 and Ex- fore feparated Silver from Gold by Calcination 5 
 t^ceQfthe ^j| Silver that was mixed with ths 
 
 peration. indeed the ’Method by Variation 
 
 is expenfive and laborious; fo as not to be very 
 advantageoufly pradtifed in the large Way of 
 Bufinefs ; though the whole has been divided in- 
 to fuch a Number of Hands, as to make the fe- 
 veral Parts come cheap: fome Operators being 
 
 wholly 
 
of Metallurgy. 399 
 
 wholly employed in making the Aqua forth ; 
 others in purifying it, or bringing it to Proofs 
 others in laminating the Silver, and difiblving it ; 
 others in feparating and reducing the Calx of the 
 Gold ; others in precipitating the Silver with Cop- 
 per ; and others again in feparating the Copper 
 from the Aqua fortis. And thus the whole Ope- 
 ration has been found to anfwer, fo long as about 
 a Dram of Gold could be recovered from a Pound 
 of Silver. 
 
 18. But there are certain Workmen of late, 7-^^ 
 who have a Method of feparating Gold from ration im- 
 Silver to much greater Profit, without the JJkP^ovet/, or 
 of Aqua fortis., or Aqua regia *, and that barely \ys^ 
 
 a dexterous Application or Management of the 
 Fire ; at lead without any colliy Additions. This 
 Method is kept as a Secret, but may, perhaps, be 
 no other than that publiflied by M. Homherg d) \ 
 which confifts in fluxing the mixed Mafs of Gold 
 and Silver with equal Parts of rough Nitre and 
 decrepitated Salt, placed at the Bottom, of the 
 Melting-Pot. By this means the Operation, in 
 the large Way, may be finifhed in a Quarter of 
 an Hour, the Gold falling to the Bottom, and 
 leaving the Silver ful'pended or detained in the 
 Salts. Another Way of eife6ling this Separa- 
 tion may depend upon a dexterous Ufe of Sul- 
 phur, which has the Power of making Silver 
 melt away from a metalline Mixture almoft as 
 cafy as Lead b ), 
 
 19. But to obtain either Gold or Silver in GoU, h(n¥ 
 abfolute Purity is no eafy Talk. For the 
 
 mon Ufes, indeed, the Methods above delivered 
 may ferve ; but for the more curious chemical 
 and philofophical Purpofes, better Ways than 
 
 a) In the French Memoirs. 
 
 b) See below § 20. 
 
 arc 
 
400 
 
 Silwr, 
 
 ho'W^ 
 
 Lecture the Eighteenth. 
 
 are commonly known and pra 6 lifed fhould 
 diicovered. To refine Gold by melting and tell- 
 ing it with Antimony, or Glafs of Antimony, 
 is generally, and even by the metallurgical Che- 
 mifts, thought a perfedl Way *, but M. Homherg * 
 has fliewn, that even this Criterion, as alfo Quar- 
 tation. Cupelling with Lead, Fluxing with Bo- 
 rax, yc. may fail, in Cafe the Gold be mixed 
 with Emery y or polTibly Tome other things. When 
 Gold is eager ^ as the Workmen call it, that is, 
 brittle, they hold it as a Secret to melt it with 
 Mercury- Sublimate. But perhaps no Gold can 
 be proved to be perfedlly pure, till it has gone 
 through all the trials hitherto known *, or even 
 fome of a more curious Nature *, particularly 
 melting with crude Antimony, and afterwards 
 cupelling the Regulus with Lead *, and at lall, 
 fufing it with Borax. Which Frocefs we recom- 
 mend to thofe who require Gold in abfolute 
 Purity for any Standard, or very curious Ope- 
 ration. 
 
 20. The Methods of obtaining Silver in Pu- 
 rity are various, and differ according to the 
 Metal wherewith the Silver is mixed or alloyed. 
 If Copper be the Alloy, the bed and cheapcft 
 Way to purify the Silver is, to calcine it with 
 half its Weight of common Sulphur-, then melt 
 the whole together ; and throw into the Pot, at 
 feveral Times a due Quantity of clean and new 
 Filings of iron, which will immediately draw the 
 Sulphur from the Silver, and Form a Scoria at top, 
 leaving the Silver free from Copper, Iron, or 
 Sulphur at the Bottom. 
 
 ^ See the French Memoirs. 
 
 Exp e r I* 
 
401 
 
 Of Metallurgy. 
 
 , Exper iment III. 
 
 ^he general Method of AJfaying and Smelting the 
 
 impurer Metals \ Copper y Leady and Iron, 
 
 21. We took four Ounces .of Lead-Ore rt- Lead-Or$ 
 duced to Powder, and mixing it with an Ounce 
 
 of the clean Tilings of pure Iron, and half an 
 Ounce of the Black Flux % \Ve mdted therni all 
 together in a new Crucible fet in a Wind Fur- 
 nace. By this Means we found the Lead clearly 
 feparated, in a Lump, at the Bottom of the 
 Crucible, after it was taken out of the Fire 
 and fuffered to cool. 
 
 22. The Method of thus working in Crucibles, 
 
 and by the Help of Fluxes, is not only too fmali, 'ffff 
 but alfo too chargeable, to anfwer in the large fff 
 Way of Bufinefs : Nor is there any Occafion for 
 being confined to this Method *, fihce Fufion in 
 a naked Fire, or in Contadl with the burning 
 Fewel, is found to a6l as a powerful Flux, and 
 get the Metal out of its Ore with Advantage. 
 
 Hence we every where find that Metals arc 
 fmelted in open Furnaces with a naked Fire. 
 
 And though this hath long been a general Pra- 
 ctice, the phyfical Reafon of it feems little 
 known *, infomuch that nothing is found more 
 wanting in Philofophical Metallurgy, than the 
 particular <?/ common Fujibn, 
 
 23. The Ores of Lead, Tin, Copper, andT’^^Rati- 
 Iron, are all commonly fufed in ContaCt with onalc. 
 the Fewel of the Furnace ; the prepared Ore 
 being at firft ftratified, or intermixed with the 
 Wood or Coals : Nor could thefe Ores be any 
 other Way fufed in a large Quantity, fo as 
 
 See Lea, I. Exp. II. 
 
 D d to 
 
402 Lecture the Eighteenth. 
 
 to acquire a metalline Form, though urged with 
 ever fo ftrong a Flame, or beat ever fo violently 
 upon by the Fire, ^whilc kept from touching the 
 Coals, by being included in a large Crucible, 
 or Melting Pot, after the Manner that Glafs is 
 made 5 or without adding fome Flux-Powder, 
 of an oily of Inflammable Nature a). Even if 
 the Ore thus treated were rich, or naturally con- 
 tained fome vifible Grains of pure Metal, this 
 Metal would only remain in almoft the fame 
 State as it was, without enlarging its bulk from 
 the Reft of the Ore : Whereas if a little pow- 
 dered Charcoal be thrown , iii, or the Ores‘ be 
 committed to a naked Wood-Fire, they pre- 
 fently refolve into Metal. 
 
 The metal’ 24. Wc might obfervc in ouf Experiment of 
 iic Nature Cupel lation ^), how extremely apt thefe imperfeft 
 ^/h^e^I^'or receive a deftruftive Alteration in 
 
 recovered the Fire, or to be burnt and reduced to Aflies, 
 or Glafs, along with the Lead ; on which Dif- 
 pofuion of theirs the Art of Cupelling depends. 
 But by contriving to melt thefe Metals in Con- 
 tad with the Coals, their metallic Form is 
 greatly preferved j efpccially as the ftony, vi- 
 trifiable Matter, wherewith fuch Ores are ufu- 
 ally mixed^ occafions them, by their clinging 
 Nature, to unite more intimately with the glow- 
 ing Coals. 
 
 Metalline 2 5. This Doftrinc receives a remarkable Con- 
 
 . Calces re’ firmation from the ufual Method of recovering 
 duetd. Metals . burnt to Aftics at the Smelting- Furnace : 
 For if the Litharge, blown off in tefting, or 
 even the Glafs of Lead, or the Aflies of any 
 other of the imperfeft Metals, be barely melted 
 in Contaft with Charcoal, they prefently recover 
 their metalline "Form. And the fame Thing 
 
 «) See LeB, II. faj/lm, I) See I. 
 
 is 
 
Of Metallurgy. 403 
 
 js jikewife effected by the Addition of any unc- 
 tuous or inflammable Matter ; whence it feems 
 to be the undtuous or inflammable Matter of the 
 Coals, which thus infinuatihg into the metalline 
 Calces, reftores their metallic Nature. And‘we 
 have leveral Times, in the Courfc of thefe Lec- 
 tures, had Occafion to obferve the great Affinity 
 there is betwixt Oils and Metals * ; infomuch 
 that their true metallic Form, or their Softnefs 
 and Ductility, feems entirely owing thereto. 
 
 26. There are three Things, therefore, to be Three 
 principally regarded in the Smelting of Ores ; 
 
 viz. (i) the Fufibility of the Metal; (2) ^ 
 
 Fufibility of the Scoria \ and (3) the Contadl or 
 Mixture of the metallic Matter with the inflam- 
 mable Part of the Coals. 
 
 27. (i) Different Metals run in different viz The 
 Manners from their dres. Thus Lead, though 
 extremely fufible in the Metal, yet runs with 
 Difficulty from the Ore ; fo as to require a con- fance 7 in 
 fiderable Violence of Fire. This Stubbornnefs, lead. 
 not belonging to the Metal, muft be attributed 
 
 to the ftony, fulphureoiis, or other mineral Mat- 
 ter, wherewith the Ore is mixed ; which Matter 
 feems to require a Degree of Heat capable of vi- 
 trifying the Lead, before the Metal will run : 
 
 But then the' Lead thus vitrified recovers a me- 
 tallic Form again, by coming in Contad with the 
 Coals. 
 
 28. In the Cafe of our prefent Experiment, 
 the Iron-Filings laying hold of the fulphureous 
 Parts of the Ore, leave the Lead at Liberty to 
 run much fooncr, and freer, from the Stone : 
 
 Where alfo the great Degree of Heat communi- 
 cated by the Iron-Filings, and their inflammable 
 Nature, muft have a conflderable Effed, at the 
 
 • See leB. VI. Sxf. II. alibi pajjim. 
 
 Dd 2 
 
 fame 
 
404 
 
 Cop- 
 
 fgr, and 
 Iron, 
 
 ne Tufihu 
 
 lityof the 
 $/ag. 
 
 Lecture the Eighteenth. 
 
 fame Time that they will not incorporate with 
 Lead, but float on its Surface in Fuflon. 
 
 29. Tin runs from its Ore with greater Eafc 
 than Lead; and is therefore fmelted in much 
 lefs Furnaces : But Copper requires an intenfe 
 Heat, or a Blaft-Furnace ; and Iron, the great- 
 efl: Heat that can be given in a Furnace : and 
 both Iron and Copper abfolutely require imme- 
 diate Contad with the Fewel employed. Hence 
 it appears, that each Metal muft have its deter- 
 minate Degree of Heat, to run it with Advan- 
 tage from the Ore or Stone. 
 
 30. (2) In order, likewife, to obtain the 
 Metal from the Ore to befl Advantage, the Sco- 
 ria^ or Slag, muft be nccefTarily made to run 
 thin and fluid ; otherwife it entangles or invif- 
 cates the Metal, and will not Jet it feparate 
 fully. And hence we frequently obferve, in the 
 Aflaying of Copper Ores, fmall grains of Metal 
 interfperfed, here and there, among the Scoria^ 
 that require to be feparated by ftamping and 
 waftiing the whole Mafs ; which Labour might 
 have been prevented, by ufing a fuitable Flux, 
 and a proper Degree of Heat, capable of pro- 
 curing a thin Fufion ; fo as to have made all the 
 Metal fall to the Bottom of the Crucible, which 
 it conftantly does when the Operation is well 
 performed. 
 
 31. To promote a thin Fufion of the Slag, in 
 the larger Furnace, it is often proper to ufe the 
 more foft and fufible Sands as a Flux ; and fome- 
 times that Loamy-Sand, which the Smiths em- 
 ploy for the Welding of Iron ; this Sand readily 
 vitrifying, and adhering to the Metal in the 
 Fire : And where it will anfwer the Charge, even 
 Litharge, or Drofs of Lead, might be ufed for 
 this Purpofe, in the larger Furnaces ; for fcarce 
 any Thing procures fo thin a Fufion of the Slag. 
 
 32. In 
 
Of Metallurgy. 
 
 405 
 
 32 . In the large Work, Sulphur is found to Sulphur 
 adhere tenacioufly to Copper *, which Metal, honAj/epa- 
 therefore, feldom comes out pure in the Furnace, 
 without repeated Fufions. The beft Method of 
 feparating this Sulphur is, to ufe a violent 
 Heat, no additional Flux at all, and the great- 
 eft Draught of Air that can any Way be procu- 
 red ; fo that all Things may confpire to burn 
 out, or carry off, the Sulphur, and introduce, 
 in its Stead, a Thing of a different Nature ; viz, 
 the inflammable Matter of the Coals ; on which, 
 as we before obferved, Ductility feems to de- 
 pend. But where Iron is mixed with Copper, 
 no better Addition is found than Sulphur, and 
 the more fulphureous Marcafites *, or what at the 
 Smelting Huts they call Marcafite Blocks : For 
 the Sulphur which thefe contain caufes the Cop- 
 per readily to run away from the Iron, and 
 leave it behind in the Furnace. And here the 
 Power which Sulphur has upon the feveral Me- 
 tals is very remarkable. We before obferved, 
 that it renders Silver almoft as fufible as Lead 
 It alfo greatly increafes the Fufibility of Iron, 
 and Regulus of Antimony ; but renders Tin 
 much lefs fufible than it is of itfelf ; and Lead, 
 even refradlory in the Fire : Whence certain 
 Rules might be formed, for the Ufe and Appli- 
 cation of Sulphur to Metals, for the Improve- 
 ment of Metallurgy. And thus the whole Arc 
 of Smelting feems to depend upon knowing the 
 Degree of Heat required by every Ore ; fo as 
 to make the Slag, as well as the Metal, run 
 thin, and evaporate or difeharge the fulphure- 
 ous Parts *, and, laftly, to introduce the proper 
 
 II. §. 18. 
 
 Dd 3 
 
 metallic, 
 
4o6 
 
 Confequert' 
 cej ofinar~ 
 tijicial Fu- 
 fiorii and 
 Separu' 
 tionj. 
 
 Metals to 
 ht cart^ 
 
 fully 
 
 fooled. 
 
 Lecture the Eighteenth. 
 
 metallic, duftile Form, by Means of an unftuous 
 gr inflammable Matter. 
 
 33. It Teems principally ov/ing to a Defe 61 : in 
 the' Knowledge of Fufion, that fo many Recre- 
 ments, or Slags, of Metails, anciently thrown, 
 as ufelefs, from the Furnacb, have been wrought 
 to confiderable Profit of late, by more Ikiltul 
 Workmen; atieafl it feerns more rational to 
 attribute the Succefs to this taufe,,.thah to 'any 
 fuppofed Growth of Metals in fuch Slags : So 
 like wife it is currently believed, that Lead 
 grows rich in Silver, by lying 'expofed to the 
 open Air, or by long covering Churches, or 
 other Buildings ; whilft perhaps it is rather ow- 
 ing to the Unfldlfulnefs of the former Workmen,' 
 who were not able to feparate all the Silver na- 
 turally contained in Lead. And thus it appears 
 certain, that the ancient Metallurgifts were un- 
 acquainted with any Way of extracting, to profit, 
 a fmall Quantity of Silver out of Copper ; which 
 is' now commonly done by an ingenious Contri- 
 vance * : Whence the ancient Copper found up- 
 on Temples, or other Buildings; frequently 
 contains silver. So likewife in the Foreji of Dean 
 they at this Day work the Slag oftheir old Iron- 
 Works over again to Profit. 
 
 34. AllMoifture, as well as too hidden Cooling, 
 proves prejudicial to the more ignoble Metals 
 after Fufion *, and fometimes dangerous to the 
 Operator. A little Water falling upon melted 
 Iron or Copper makes them expand with prodi- 
 gious Violence, and difeharge thcmfclves abroad 
 with a Force like that of a Canon : And even 
 hidden cooling ‘"will often occafion the Surface 
 of the Metal to crack, and force the more in- 
 ternal Part, not yet fet or fixed, to iffue out to 
 
 • See below, 35. 
 
 a con- 
 
Of Metallurgy. ‘407 
 
 a confidCiTable Diftance ; whence either Lofs of 
 the Metal or Mifchief may enfuc. But to pre- ' 
 vent thefe ill EfFcds, after Cupellation* it is 
 ufual for the Operator to throw a Quantity of 
 Water, all at once, upon the Lump of Silver, as 
 it lies in the Teft, at the Moment that it begins 
 to grow rigid ; for thus the Water, by its Cold- ' 
 nefs, fuddenly makes fo thick a Cover upon the 
 Surface of the Silver, that the hotter infide 
 Parts cannot break through the upper : 
 
 Whence that fpringing, or fpouting out, of the 
 Silver, which we fo'metimes fee in the fmaller 
 Way of allaying upon the Teft, when the Metal 
 fpontaneoully cools, is entirely prevented. 
 
 35. We have already confidered how Gold The igno- 
 and Silver are to be feparated when mixed a) ; hier Metals 
 we fliould alfo know how the lefs noble Metals 
 may be feparated from one another : This is 
 done either by Means of Fire alone, or by Means 
 of Lead. Thus Copper, being more fufible viz. 
 than Iron, will, in a proper Furnace, melt, and /row Cop- 
 run entirely from it ; whilft the Iron is not 
 made to flow with the fame Degree ^of Heat as 
 melts the Copper, or elfc flicks behind in the 
 Slag. After the fame Manner Lead, being from 
 more fufible than Copper, readily funs away 
 from it, in a Furnace kept of a due Heat for 
 the Purpofe, A Mixture of Iron and Lead is 
 feparated in the fame Mariner; the Iron floating 
 upon the Surface of the Lead. Copper,, Tin, * 
 Iron, Antimony, we before obferved might 
 
 be Icparated from Gold or Silver, by telling 
 with Lead h ) ; but then the ignobler Metals are 
 loll. And where only a fmall Proportion of 
 Silver is mixed with a large one of Copper, this 
 Method would prove ufelefs, or prejudicial : 
 
 See Exp, II, h) Exp.l^ 
 
 Dd 4 
 
 Nor 
 
4o8 Lecture the Eighteenth. 
 
 Stiver Nor can a fmall Proportion of Silver be well 
 from Cop- ieparated from Copper, by any Method hitherto 
 known ; fo as to preihrve the Copper pure, or 
 eafily recoverable : Whence at the Smelting- 
 Huts the Method is, to get the Silver out of 
 imperfed Copper, whilft it ftill remains mixed 
 with its own Sulphur, under the Form of what 
 they call Black Copper, This they melt, and 
 make to run among a large Proportion of 
 melted Lead *, then calling the Mixture out into 
 large Blocks, thefe are carried to a particular 
 Furnace, and there fet upright, fo as that the 
 Fire, being lighted at top, may commodioufly 
 play between them. And thus the Lead melts 
 away trom the Blocks, carrying with it the Sil- 
 ver before contained in the Copper ; the Blocks 
 of which Metal are now left hollow, porous, 
 fpungy, and wrinkled. Thefe exhaufted Blocks 
 are then removed xo a hotter Furnace, in order 
 to be farther drained of their Lead. The lall 
 Remains are now, in another Furnace, reduced 
 to perfedl popper ; and the whole Parcel of 
 Lead, tl^w^nriched, committed to the Teft, in 
 order feparate the Silver. 
 
 C'f}erOre 3^. In the fame Manner may Copper Ores be 
 tejied' a.ffayed, by telling them with a fmaller Propor- 
 tion of Lead than is ufed to Silver Ores ; tho’ 
 this Operation requires a great Degree of Care 
 and'Exa6lnefs, to prevent the Copper from be- 
 ing carried off with the Lead, or vitrified. So 
 likewife when Copper happens to be mixed with 
 Iron, the bed Method of feparating them, in 
 the Way of Effay, is to melt them with Lead; 
 which readily imbibes the Copper, but throws 
 the Iron to the Surface ; where being entangled 
 with the vitrified Scoria of the Lead, it may be 
 taken off, and the Copper thus brought to a 
 great Degree of Purity *, though indeed it is apt 
 
 to 
 
Of Metallurgy. 409 
 
 to lofe a little of its Dudbility, on Account of fome 
 very minute Proportion of Lead, or its Fumes, 
 remaining therein, 
 
 37. We have not here confined ourfelves tofheDoc- 
 the Confideration of one Metal more than 
 
 ther; but endeavoured, under the prefent 
 periment, to (hew the Ways of treating all the 
 ignobler Kinds, or working them, in the beft 
 Manner, from their Ores. It is cafy to apply 
 this general Dodlrine, occafionally, to the Treat- 
 ment either of Lead, Tin, Copper, or Iron. 
 
 Experiment IV. 
 he Method of making Prince^ s> Metal. 
 
 38. We took fix Ounces of Copper, and melt- A mixed 
 ing it in a Wind -Furnace, added to it an Ounce 
 
 of Zink; then ftirring the whole well together, 
 we immediately poured out the Metal. The 
 Copper and the Zink may be put into the Cru- 
 cible together, if firfi: covered over with the 
 Black Flux ; which prevents the Avolation of 
 the Zink, or preferves its metalline Form. 
 
 39. This is an expeditious Method of making Bra/show 
 a fine Kind of Brafs ; whereas the common Me- made. 
 thod with Lapis Calaminaris requires a confide- 
 
 rable Length of Time, and a violent Fire : For 
 this Purpofe they calcine and powder the Cala- 
 my ; then mix it with a little Charcoal-duft ; and 
 to feven Pounds of this Mixture add .five of 
 Copper-Plates ; then giving eleven or twelve 
 Hours Fire, the Copper imbibes about one. third 
 of its Weight of the Calamy. 
 
 40. It is here remarkable that the Calamy, 
 
 though no compleat metallic Body, nor of Calamy. 
 
 ble, fhould yet concrete along wifh the Copper, 
 
 fo as not only to increafe its Weight, but alfo to 
 
 extend 
 
4io: Lecture THE Eighteenth. 
 
 extend with it under the Hammer ; which Zink, 
 inf making the Prince’s Metal, does not do, 
 though it appear in ‘all Refpefts of a more mc-^ 
 tallic Nature than Calamy. 
 
 AndZink^ 41. The Agreements and Difagreements of 
 * thrfc* two Bodies, Zink and Lapis Calaminaris^ 
 may deferve to be farther enquired into, by 
 particular Experiments. . The Inflammability of 
 Zink is very remarkable ; for it burns durably 
 of- a bluifli white Flame in the Fire; and thus 
 refolvcs into a white Calx. . 
 
 Imitations 42. Many curious Phsenomena, and unexped- 
 ed Refults, happen upon mixing metallic and 
 mineral Bodies in the Fire ; all which deferve to 
 be tried, and noted, as Fadls that might at leaft 
 direft to the difeovery of feveral new and ufeful 
 Mixtures, or Compofitions of Metals. We might 
 be encouraged to profecute thisr Enquiry, by 
 thofe pretty Imitations of Gold, lately introdu- . 
 eed for the making of Watches, Buckles, Cane- 
 Hom- heads. Snuff-boxes, But perhaps a better 
 
 berg’i. Imitation of Gold, for thefe and many other 
 
 MttaL Purpofes, may be obtained by M. Homberg's 
 Method of treating Copper with Quickfilver : 
 For if an Amalgam be made of one Part pure 
 Copper, and three Parts Quickfilver ; and the 
 Amalgam be boiled in River- Water for two 
 Hours ; then the Quickfilver diftilled off, and 
 cohobated once ; the remaining Copper, being 
 now fufed, will be found of a beautiful Gold 
 Colour, and more dudile than common Cop- 
 per 5 fo as to become well fitted for Watch- 
 work, Gilding, and the finer Machines and 
 Utenfils. 
 
 E X P E R i- 
 
of Metallurgy^ 4 1 1 
 
 Experiment V. 
 
 Method of converting Iron into Steel. 
 
 43. ^We took a few Pieces of foft Iron -Wire, SudmaJe. 
 and burying them in a clofc Crucible, full of 
 powdered Charcoal, fet the whole in a Wind- 
 Furnace, -for two or three Hours ; then taking 
 
 out the Pieces of Wire we found them changed 
 to Steel. 
 
 44. The Method of making Steel has been The an- 
 ufually kept as' a Secret, and at prefent there 
 
 arc but very few Steel-makers in England : The 
 ancient Method was; to keep flender Bars of Iron 
 ignited, for feveral Hours, in a melted Mixture 
 of Iron and vitrefcible Sand ; then taking out 
 the Bars, forging them, and immediately plung- 
 ing them, whilft hot, into cold Water; after- 
 wards forging them again, till they would eafily 
 fhap, and appear white, and of a clofc Texture, 
 or Steel-Grain, w^hen broke. 
 
 45. The prefent Method is, to ftratify a large Themodern 
 Number of flender Iron Bars with powdered Method. 
 Charcoal ; to fill a Furnace with them, in the 
 
 Form of a long Cheft; and then to keep up a ftrong 
 Fire, but fo as not to melt the Iron, for two or 
 three Days together. And thus at lengthy when 
 the Furnace is cold, the Bars are taken out 
 unaltered in their external Form : But they may 
 be bliftered according to the Pleafure of the Ope- 
 rator, by ufing Quicklime along with the pow- 
 dered Charcoal. 
 
 46. The whole Secret of making Steel fecms 
 to depend upon excluding the Air from the 
 Iron to be wrought upon. Accordingly if 
 large Ball of Iron be kept fo hot, for fomeTime, 
 that its external Surface ihall melt, and run like 
 
 Water, 
 
Cafe^ 
 
 hard- 
 
 gftifig. 
 
 412 Lecture the Eighteenth. 
 
 Water, the internal Part of the Ball will, at 
 the fame Time, be converted into true Steel. 
 And hence appears the Reafon why certain 
 Knots, or Spindles, of Iron are fometimes found 
 in the Middle of Caft^Work, fo hard that no 
 Tool will touch them. 
 
 47. The Art of Cafe-hardening is a leffer 
 Degree of Steel- making ; and is pradlifed by bak- 
 ing Rafors, Files, Knife-Blades, in a Kind of 
 Oven, ftratified with powdered Charcoal, Hoofs, 
 Horns, and the like, fo as to exclude the Air •, 
 and thus, by baking, to give a Coat of Steel to 
 Inftruments, fome Depth below their Surface. 
 48. But the Making of the beft Steel depends 
 5/7^/7wupon the Nature of the Iron employed, or its 
 madf. Ore ; and ufually requires a proper Mixture of 
 feveral Kinds together, as well as Perfedlion in 
 the Art of Tempering ; which, according as it 
 is managed, fuits* the Steel for different Ufes. 
 Thus Gravers are of one Temper, Drills of an- 
 other, Watch-Springs of another. Razors of an- 
 other, fsfr. Which Tempers are given them by 
 being quenched with different Heats in Tallow, 
 Water, or certain Liquors, Juices, or the like. 
 
 Th leji 
 
 Axioms and Canons. 
 
 1. We learn from the foregoing Enquiry, 
 That different mineral and metallic Matters bear 
 different Relations to melted Lead in Fufion : 
 Whence fome of them will not mix therewith, 
 but float on its Surface ; others evaporate, 
 and others vitrify with it; whilfl: Silver and Gold 
 remain unaltered by it, and unimpaired *. 
 
 2. That the nobler Metals have nearly the 
 fame Relation to Qiiickfilver, as they have to 
 
 I. 
 
 melted 
 
Of Metallurgy. 
 
 melted Lead ; being readily drunk up by them 
 both, and thus feparated from other heteroge- 
 neous Matters a). 
 
 3. ThatTefting, in the large Way, is improvc- 
 able by finding a properer Matter than Bone- 
 Afhes for the making of Tefts ; by working 
 without Bellows ; and again by ufing Pit-Coal, 
 and a well contrived Furnace a). 
 
 4. That the Art of AfTaying is hitherto imper- 
 fedf \ but capable of receiving confiderable Im- 
 provements from chemical and mechanical Know- 
 ledge a). 
 
 5. That the troublefome and expenfive Me- 
 thod of feparating Gold from Silver by Varia- 
 tion., may be advantageoufly fuperfeded, or fet 
 afide, by Means of Fufion, or a dexterous Ma- 
 nagement of the Fire h), 
 
 6. That Gold and Silver are rarely rendered 
 abfolutely pure, or feparated from all other 
 Kinds of metallic or mineral Matters ; and that 
 to purify them to fuch a Degree requires the Ufe 
 of better Methods than thofe commonly employ- 
 ed : though the Thing is ftill performable by 
 Art, and a fuitable Procefs h). 
 
 7. That the particular Hiftory of common metal- 
 lic Fufion is wanting, for the Improvement of 
 Metallurgy r). 
 
 8. That when the Ore of an imperfect Metal 
 is in immediate Contad with the Fire or Fewel, 
 it yields more and better Metal, than when con- 
 tained in a Crucible, or kept from touching the 
 Coals c), 
 
 9. That a languid Fire leflens the Yield of an 
 Ore *, but a brifk one, if not too long continued, 
 increafes it d), 
 
 a) Exp. I. b') Exp. II. 0 BL ^ 
 
 See alfo Lect. XVII. 
 
 + 13 
 
 10. That 
 
, Lecture the Eighteenth. 
 
 10. That the Bufinefs of Smelting in* Perfec- 
 tion depends ( i ) upon ufing a Degree of Eire 
 fuitcd to the Ore; (2) procuring a quick and 
 thin Fufion of the Sceria ; and f 3) a clofc Con- 
 
 . ta( 5 t of the Metal with the Fewel, or Coals, em- 
 ployed a). 
 
 11. tW Sulphur has different Effe< 5 ls up, on 
 the different Metals ; which Effeds being well 
 
 . noted. Rules of Pradice might^be thence deri- 
 ved, for the farther Improvement of Metal- 
 lurgy a). 
 
 12. That metalline Recrements, or the Slags 
 of Metals once fmelted, have been wrought over 
 
 , again to profit, on Account of the imperfed Man- 
 ner wherein the Ores , were originally treated for 
 . their Metals a). 
 
 13. That the ignobler Metals are feparable 
 f from each other by the Application of proper 
 
 Degrees of Heat; fo as to make the more fu- 
 fible melt away from the ^lefs fufiblc; at leaft 
 with the Affiftance of Lead a), 
 
 14. ^That all Metals are reducible, by burn- 
 ing, or Calcination, to terreftrial Powders, or 
 Calces ; which, by being melted with any in- 
 
 , flammable Matter,* affume their metalline Form 
 ^ again a). 
 
 15 That the great Enemies to Dudility, or 
 r the true metallic Nature, are Sulphur; Cobalt, 
 and Things compounded thereof b ) ; but that all 
 unduous or inflammable Bodies are friendly to 
 Metals, and promote or reftorc their Dudility, 
 when melted therewith r). 
 
 - 16. That Copper may be made to approach 
 the Colour of Gold, and at the fame Time not 
 lofe, but increafe, its Dudility, by being amal- 
 gamated with, and diftilled from, Quickfilver ; 
 
 s) Exp. III. 0 IR- See alfo Lta. XVII. c) Exp. III. 
 
 and 
 
Of Metallurgy. 
 
 and that probably many artificial or compound 
 Metals are difcoverable,-by mixing various me- 
 talline and mineral Bodies together ; fo as greatly 
 to enrich and improve the Art of Metallurgy a\ 
 
 17. That Steel is made by a proper Applica- 
 tion of Fire to Iron, in a dole Place, fo as to pre- 
 vent the open Air from communicating freely 
 with the Iron h). 
 
 18. That Metals receive particular Alterationa 
 in their Texture or Confiftence, , according to 
 the Nature of the folid Subftance or Liquor, 
 wherein they are quenched or cooled h)* 
 
 1 9. That, in general. Ores are no more than 
 a natural, loofe ‘Mixture of metallic Matters, 
 along with earthy and fulphureous ones Whence 
 artificial Ores may be readily madej* by calcining 
 a Metal with Sulphur, and mixing it with Earth \ 
 fo as, with Heat, to form folid Lumps of Ore, 
 refembling thofe Dug out of Mines c). 
 
 20. That numerous Experiments remain to be 
 made, Fafts of Nature, or Obfervations, to be 
 regiftered, and Relations of Bodies to be found, 
 before this ufeful Subjed of Metallurgy* can ^bc 
 brought to Perfeftion d). 
 
 m) Exp. IV. b) Exp. V. c) Sec Led. XVH. and * 
 XYlll.paJim. * II. Ill, IV. V. 
 
 LECf 
 
[ 4i6 ] 
 
 L E G T U R E XIX. 
 
 CONTAINING 
 
 Pyrotechny; Or Experiments relating to 
 ' ' Gunpowder, Explolions, and Phofphori. 
 
 I. rr^HE prefent Defign is to enquire into 
 Jl Nature of Gunpowder, Explofions, 
 and Phofphori *, and to try if any ufeful 
 Do6lrine or Difcoveries may be thence derived, 
 for the Improvement of Chemiftry and Natural 
 Philofophy. We therefore propofe (i) to examine 
 into the Nature and Compofition of Gunpowder, 
 with the Ways of trying and improving it; 
 (2) to fliew fome of the more remarkable Kinds 
 of Explofions ; (3) tp examine fome of the more 
 eminent Phofphori ; and (4) to deliver the Doc- 
 trine pointed out by this Kind of Experiments. 
 
 ^he Intent Experiment, therefore, will Ihew 
 
 ^ the Method of making Gunpowder; o\jiv fecond 
 feriments, the Method of making the Pulvis and Jurum 
 fulminans', our thirds a Method of producing 
 Heat and Fire by the Mixture of Sulphur and 
 Iron Filings ; our fourth^ a Method of produ- 
 cing Corufcations with Oil of Vitriol and Iron 
 Filings; ouv fifths a Method of producing Fire 
 and Flame by the Mixture of two cold Li- 
 quors ; and our ftxth Experiment will Ihew the 
 Method of making the liquid Phofphorus of 
 Urine. 
 
 E X P E R I- 
 
Of Pyrotechny. 417 
 
 E X P E R I M 6 N T I. 
 
 ^he Method of making Gunpowder, 
 
 1. We took four Ounces of refined Sak-Petre, Guvpo'rv* 
 an Ounce of Brimftone, and fix Drams 
 Small-Coal ; thefe we reduced to fine Powder, 
 
 and continued beating them, for fome Time, 
 in a Stone- Mortar, with a Wooden Peftle ; 
 wetting the Mixture, betv/een whiles, v/ith Wa-' 
 ter, fo as to bring the whole into an uniform 
 Pafle ; which we then reduced to Grains, by 
 pafTing it through a Wire-Sieve fit for the Pur- 
 pofe : And in this Form, being carefully dried, 
 it became the common Gunpowder. 
 
 2. We formerly fhewed the Way of refining \'itre h’w 
 Salt-Petre for the making of Gunpowder In pul^eri^td 
 order to reduce this Salt to Powder, they dif- readily. 
 folve a large Quantity of it in as fmall a Propor- 
 tion of Water as poflible *, then keeping it con- 
 tinually ftirring over the Fire, till the Water 
 exhales, a white dry Powder is left behind. 
 
 3. In order to purify the Brimftone employed, "^heSuU 
 they diflblve it with a very gentle Heat ; then^^"''^*''’'" 
 feum and pafs it through a double Strainer. Ir 
 
 the Brimftone fhould happen to take Fire in the 
 melting, they have an Iron-Cover that fits on 
 clofe to the melting Veflel, and damps the 
 Flame. The Brimftone is judged to be fuffi- 
 ciently refined, if being put between two hot Iron 
 Plates, it melts into a Kind of red Subftance, 
 without yielding any fetid Odour. 
 
 4. The Coal for the making of Gunpowder, fhe Coal 
 is either of Willow or Hazel, well charred prepared. 
 in the ufual Manner, and reduced to Powder : 
 
 And thus the Ingredients are prepared for mak- 
 
 * See XIII. 
 
4,i8 
 
 TheStawp- 
 
 i>£. 
 
 Rationale 
 of Gun- 
 ■p'jvjder. 
 
 Lecture the Nineteenth. 
 
 ing this Commodity. But as thefe Ingredients 
 require to be- intimately mixed, and as there 
 v/ould be Danger of their firing if beat in a dry 
 Form, the Method is to keep them continually 
 moift, either with Water, Urine, or a Solution 
 of Sal-Ammoniac, and to continue thus {lamp- 
 ing them together for 24- Hours *, after which 
 the Mafs is fit for corning, and drying in the 
 Sun or otherwife, fo as feduloufly to prevent 
 its firing. 
 
 5. The explofive Force of Gunpowder is now 
 a thing commonly known , but the phyfical Rea- 
 fon thereof may not, perhaps, be hitherto fuf- 
 hciently underflood. In order to explain it, 
 let us obferve (i) that Salt-Petre, of itfelf, 
 is not inflammable •, and though it melts in the 
 Fire, and grows red hot, yet it does not explode, 
 ualefs it comes in immediate Contad with the 
 Coals; (2) that Brimflone eafily melts at the 
 Fire, and than readily catches Flame; (3) that 
 powdered Charcoal readily takes Fire, even from 
 the Sparks yielded by a Flint and Steel ; (4) that 
 if Nitre be mixed with powdered Charcoal, and 
 brought in Contad with the Fire, it burns and 
 flames ; (5) that if Sulphur be mixed with pow- 
 dered Charcoal, and Fire applied to it, part 
 of the Sulphur burns (lowly away, but not much 
 of the Charcoal ; and (6j that if a lighted Coal 
 be applied to a Mixture of Nitre and Sulphur, 
 the Sulphur prefently takes Fire, with fome De- 
 gree of Explofion, leaving a Part of the Nitre 
 behind ; as we fee in making the Sal PrunelU 
 and, Sal Polychreftum. 
 
 6. Thefe Experiments duly confidered may 
 give us the chemical Caufe ot the flrange explo- 
 iive Force of Gunpowder : For each Grain of 
 this Powder confifting of a certain Proportion 
 of Sulphur, Nitre, and Coal, the Coal prefent- 
 
Of Pyrotechny. 419 
 
 ly takes Fire, upon Conta6l of the fmallefl Spark • 
 whereupon both the Sulphur and the Nitre 
 immediately melt, by Means of the Coal inter- 
 pofed between them, and burft into Flame ; 
 which, fpreading from Grain to Grain, propa- 
 gates the fame Effedl almoft inftantaneoufly ; 
 fo that the whole Mafs of Powder comes to be 
 fired : And as Nitre contains a large Proportion 
 both of Air and Water, which are now violent- 
 ly rarefied by the Heat, a Kind of fiery explofive 
 Blaft is thus produced ; wherein the Nitre 
 feems, by its aqueous and aerial Parts, to a6t 
 as Bellows to the other inflammable Bodies, Sul- 
 phur and Coal, blow them into a Flame, and 
 carry off their whole Subftance in Smoak and 
 Vapour. 
 
 7. The Difcovery of this Compofition was acci- Its Dlfcg- 
 dental, and perhaps owing to that common Ope- 
 ration of fulminating Nitre with Sulphur, for 
 
 the making of Sal PrunelU. It appears to have 
 been known long before the Time of Schwartz^ 
 as being particularly mentioned by Friar Bacon, 
 
 8. The three Ingredients of Gunpowder zxzl'he hgre- 
 mixed in various Proportions, according as the 
 Powder is intended for Mufquets, Great 
 
 or Mortars : Though thefe Proportions feem 
 not to be hitherto perfedlly adjuflcd, or fettled 
 by competent Experience. 
 
 9. There are two general Methods of examin- How tried 
 ing Gunpowder; one with regard to its Purity, 
 
 the other with regard to its Strength. Its Purity 
 is known, by laying two or three little Heaps 
 near each other upon white Paper, and firing 
 one of them ; for if this takes Fire readily, and 
 the Smoke rifes upright, without leaving any 
 Drofs or feculent Matter behind, and without 
 burning the Paper, or firing the other Heaps, 
 it is efleemed a Sign that the Sulphur and Nitre 
 
 E e 2 wer^ 
 
420 
 
 Lecture the Nineteenth. 
 
 were well purified; that the Coal was good ; 
 and all the three Ingredients were thoroughly 
 incorporated together. But if the other Heaps 
 alfo take Fire at the fame Time, it is prefumed 
 that either common Salt was mixed with the 
 Nitre, or that the Coal was not well ground, 
 or the whole Mafs not well beat and mixed 
 together; and if the Nitre or Sulphur was not 
 well purified, the Paper will be black or fpot- 
 ted. 
 
 How as to lo. In order to try the Strength of Gunpow- 
 strength. there are two Kinds of Inftruments in Ufe ; 
 but neither of them appear more exadl than the 
 common Method of trying to what Diftance a 
 certain Weight of Powder will throw a Bali 
 from a Mufquet. 
 
 How II. To increafe the Strength of Powder, it 
 feems proper to make the Grains confiderably 
 ^ ‘ large, and to have it well fifted from the fmall 
 Duft. We fee that Gunpowder reduced to 
 Dull has little explofive Force ; but when the 
 Grains are large, the Flame of one Grain has 
 a ready Paflage to another, fo that the whole 
 Parcel may thus take Fire nearly at the fame 
 Time; otherwife* much Force may be loft, or 
 many of the Grains go away, as Shot, unfired. 
 
 12. It fhould alfo feem, that there are other 
 Ways of increafing the Strength of Powder ; par- 
 ticularly by the Mixture of Salt of Tartar : But 
 perhaps it may be improper to divulge any Thing 
 of this Kind, as Gunpowder feems already fuf- 
 ficiently deftrudive. 
 
 White 13. There has been much talk of a white Pow- 
 Powder, der ; which, if it anfwered the Character given 
 it, might be a dangerous Thing : For ’tis pre- 
 tended that this white Powder will throw a Ball 
 as far as the Black, yet without making any Re- 
 port. But none of the white Powder which we 
 
 have 
 
Of Pyrotechny. 421 
 
 have feen anfwers this Charadler ; being, as 
 we apprehend, commonly made cither with 
 Touch-wood or Camphire, inftead of Coal. The 
 mod dangerous white Powder, if it may be fo 
 called, is condenfed Air*, which, though able 
 I to difeharge a Ball, with great Force, to a con- 
 I fiderable Diftance, makes not a loud Report ; 
 
 efpecially when not violently condenfed, as it 
 ; need not be to have pernicious Effects. 
 
 I 14. And how far Wind-Guns are improve- Wind- 
 able, has not, perhaps, been well confidered. 
 
 Some of them we have feen difeharge a great 
 Number of Bullets fucccffively *, even the lad* 
 whereof would go through an Inch-Plank, at 
 - the Dldance of feveral Yards : So that this 
 Machine might anfwer the fame End as a Muf- 
 quet. But whether it be pradicable to make 
 great Guns in the fame Manner, is another Con- 
 lidcration *, and chiefly depends upon finding a 
 Spring fufliciently drong to refid the violent 
 Force wherewith Air might be condenfed by the 
 Ufeof a Winch, 
 
 Experiment II. 
 
 Pulvis and Aurum fulminans 
 
 15. We took three Ounces of purified Nitre, Pulvis fal- 
 t wo Ounces of Salt of Tartar, and one Ounce 
 
 of Brimdone, and ground them well together 
 in a Mortar ; then putting a fmall Quantity, as 
 about half a Dram, of this Powder upon an 
 Iron Plate, and placing it over a gentle Fire, as 
 foon as the Powder jud began to melt, it made 
 a fmarc and loud Explofion. 
 
 16. The mod philofophical Way of accounting its 
 
 for this EflTed of the Pulvis fulminansy is by fup- accounn* 
 pofing that the acid Spirits of the Nitre and '^^'* 
 
 E e j Sulphur 
 
422 
 
 Lecture the Nineteenth, 
 
 Sulphur, being loofened by the Heat, rufii to- 
 wards one another, and towards the Salt of 
 Tartar, with fo great a Violence, as, by the 
 Shock, at once to turn the whole into Vapour 
 and Fume. 
 
 A.urum 17* We diflblved a few Grains of fine Gold 
 fuiminans in Aqua-Regia^ precipitated the Solution with 
 yre^ared. 5^]^- q£ Xai'tar, and thus obtained a Powder, 
 which we dried with a very gentle Heat, h 
 fingle Grain of this Powder being laid upon 
 the point of a Knife, and held over a lighted 
 Candle, prefently went off, with a very brifk 
 and loud Report. 
 
 Its odd 18. This Atirum fuiminans has otherremark- 
 Pro^ertics. Properties*, for (i) it does not, like the 
 Pulvis fuiminans and Gunpowder, require the 
 Application of adlual Fire to make it explode ; 
 but though prepared with two of the moll: fixed 
 Bodies, Gold and Salt of Tartar, yet is fo vo- 
 latile as to fly off, and give this loud Report, 
 with a lefs Degree of Heat than fuffices to kindle 
 any of the mofl inflammable Bodies ; or even by 
 being ftrongly rubbed in a Mortar, or dried on 
 a hot Furnace : ; 2) It exerts its explofive Force 
 m vacuo^ as well as in the open Air \ and when 
 made to explode in the exhaufted Receiver, a 
 fine Gold Dufl: has been found fticking to the 
 Sides of the Glafs. (3) The Addition of a little 
 Brimflcne to this Powder takes away its fulmi- 
 nating Property ; fo that after having been melt- 
 ed therewith, the Gold is fet loofe, and may be 
 eafily recovered, in its native form, by fluxing ip 
 v'ith Borax. 
 
 r/^/'Ratio* ^ 9- Flence it fnould feem that the Body of the 
 iiale. Gold in this Powder is fubtilely divided by the 
 A(fticn and Interpofition of the Parts of the com- 
 pound Menifruum ; which Menflruum being of 
 
 - an 
 
Of Pyrotechny. • 423 
 
 an aqueous and aerial Nature, and its Parts 
 ■clofely wedged in betwixt the fine ponderous 
 Parts of the Gold in the Aurum fulminans^ when 
 this Powder corner, any way, to feel fuch a De- 
 gree of Heat as fufiices ftrongly to ratify and 
 expand the aqueous and aerial Particles, they 
 burft with Violence from their Prifons, and fcat- 
 ter the dully Particles of the Gold around. 
 
 Experiment III. 
 
 Produ 5 lion of Heat and Fire^ by the Mixture of 
 Sulphur and Iron -Filings, 
 
 20. We took two Pounds of clean Iron-Fil- The firing 
 ings,and as much common Brimllone, and beat- Mixtureof 
 ing them together for fome Time, in a Mortar, 
 
 with the Addition of Water, we brought the e^liained, 
 whole to a Kind of Palle ; which being clofe 
 prell into an earthen Pot, and fet in a Chim- 
 ney, it in a fhort Time begun to grow hot, and 
 at Length took fire. 
 
 21. This Mixture never fails to take Fire, if 
 the Quantity be large *, but if it be fmall, the 
 Palle only heats and cracks, in feveral Places, 
 fo that hot Vapours ilTue out thereat. But if 
 the Heat continues fufficiently long, the whole 
 Mafs will be changed into one uniform Sub- 
 fiance *, which, being ground and boiled in Wa- 
 ter, affords good Vitriol of Iron ^ : Vv^hence it 
 is manifell, that the Acid naturally contained 
 in the Brimllone enters the Body of the Iron, 
 and diflblves it. This AiStion may therefore be 
 the Caufe of the Effcd ; efpecially if we confidcr 
 that Sulphur confills of an unduous or inffam- 
 
 See below §. 26. 
 
 E e '4 mable. 
 
Lecture. THE Nineteenth. 
 
 mable, as well as an acid Part : For this inflam- 
 mable Part of the Sulphur, doubtlefs, takes Fire 
 in the violent Conflid betwixt the Iron and the 
 Acid of the Sulphur. 
 
 And ap^ 22. This Experiment, if duly attended to 
 
 plied, and applied, may, in the ufual Way of Philo- 
 fophers, account for feveral Phasnomena of Na- 
 ture ; fuch as burning Mountains, fubterraneous 
 Fires, Earthquakes, hot Baths, Thus, for 
 infcance, as there are large Quantities of Iron- 
 Stone, and Sulphur, found in the Bowels of the 
 Earth ; as alfo Marcafites, which are a Mixture 
 of the two *, when thefe come to be wet, as 
 they may, on many Occafions, with Water, ’tis 
 eafy to conceive, that they muil heat, fwell, fer- 
 ment, explode, and yield a hot Steam or Va- 
 pour, which forcing its Way through certain 
 Caverns of the Earth, fhall produce Earth- 
 quakes, or violent Strugglings, of longer or 
 fhorter Duration, till the Force finds vent, or 
 expires through fome Cranny into the Atrno- 
 fphere. Sulphureous Vapours certainly abound 
 in the Bowels of the Earth,. and ferment, and 
 confiid with Minerals, fo as to take Fire, and 
 make fudden Corufeations, or Explofions ; and 
 if confined in the Caverns of the Earth, fome- 
 times burft and fliudder thofe Caverns to Pieces. 
 At which Time the hot V apours, generated by 
 the Explofion, and expiring through the Pores 
 of the Earth, may raife Tempefts and Hurri- 
 canes, or make the Ground fink into Chafms, 
 or the Sea boil up in certain Places. Thefe ful- 
 phureous Vapours at other Times afeending into 
 the Atmofphere, may there ferment along with 
 other Matters, take Fire, and thus Occafion 
 Thunder, Lightning, the Aurora Borealis^ and 
 other fiery Meteors ; At leafl: this feems one 
 
 probable 
 
Of Fyrotechny. 425 
 
 probable Caufe of fuch Effects, and has a Founda- 
 tion in Nature 
 
 Experiment IV. 
 
 Cor uj cations produced by means of Oil of Vitriol 
 and Iron. 
 
 23. We took a cut Body, capable of holding Artificial 
 two or three Quarts ; and put into it three 
 Ounces of Oil of Vitriol, and twelve of com- 
 
 mon Water •, then warming the Mixture a little, 
 we threw in, at feveral Times, two Ounces, or 
 more, of clean Iron-Filings ; upon which an 
 Ebullition, and white Vapours, arofe ; then pre- 
 fenting a lighted Candle to the Mouth of the 
 Body, the Vapour took Fire, and at the fame 
 Time afforded a bright Fulmination, or Flafli 
 like Lightning. The Candle being feveral Times 
 applied, in the fame Manner, afforded the like 
 Corufeation ; during which we fomecimes found 
 the Glafs filled with a Flame that reached, and 
 circulated, to tFe Bottom of the Liquor •, and 
 fometimes the Flame only rofe into the Neck of 
 the Glafs. 
 
 24. This Experiment will not fucceed, unlefs Cautions. 
 the Oil of Vitriol be largely diluted with Wa- 
 ter, to make the Menftruum fit for diffolving 
 
 the Metal. ’Tis alfo rcquifite to heat the Li- 
 quor a little, in order to promote the Solution, 
 that the Vapour may afeend the freer : But if 
 the Liquor be too hot, the Vapour will rife too 
 faft *, and fo, when the Candle is applied, only 
 take fire in the Neck of the Glafs, without mak- 
 ing any remarkable Fulmination. 
 
 * See Sir Ifaac Ve’wtons ^eries^ at the End of his Optics*, 
 and M. Lemerj% Paper upon the Subject, in the French Me- 
 nioirs. 
 
 25. This 
 
426 Lecture the Nineteenth. 
 
 Rationale, 25. This Experiment appears to have a great 
 Affinity with the preceding, and to depend upon 
 nearly the fame Principle ; the Oil of Vitriol 
 being a very powerful Acid, correfponding to 
 that of Brimftone ; and Iron, in itfelf, con- 
 taining fomething that is properly fulphureous, 
 or inflammable. It ffiould feem, however, that 
 it is not the Sulphur of the Iron alone, but 
 that fome fulphureous Part of the Oil of Vi- 
 triol alfo contributes to the Effed •, for Spirit of 
 Nitre, or Aqua fortis^ being ufed in this Cafe, 
 produce no Fulmination : But the Spirits of Salt, 
 of Sulphur, and of Allum, which are all ful- 
 phureous, have here the fame Effed as Oil of 
 Vitriol. 
 
 Difcc<very ^6. The Experiment feems to have been ac- 
 *ndVje, cidentally difcovered, by inadvertently approa- 
 ching a Candle near the Mouth of the Glafs, 
 whilft Iron was diflfolving in diluted Oil of Vi- 
 triol, in order to make the common Vitriol of 
 Iron ; for if what remains in the Glafs after the 
 Fulmination is over, be boiled, filtred, evapo- 
 rated, and cryftallized, it affords this Vitriol in 
 great Perfedion, like what we before obferved 
 of the Mixture of Iron-Filings and Sulphur a), 
 
 27. We would recommend it to the curious 
 in Chemiftry, to endeavour to colled, and, il" 
 poffible, to condenfe, a Qiiantity of the fulphu- 
 reous Vapour generated in the prefent Experi- 
 ment: For this Vapour has not the fetid Smell 
 of Brimftone ; but is, perhaps, fomewhat like 
 that volatile, aerial Spirit, which gives Virtue to 
 certain mineral Waters h)» 
 
 a) See above, §.22. 
 
 b) See Hoffman of Mineral Waters. 
 
 Exp e r I- 
 
of Pyroteehny. 
 
 427 
 
 Experiment V. 
 
 Fire and Flame produced hy the Mixture of two 
 cold Liquors, 
 
 28. We took two Drams of flrong and frefh on of 
 Spirit of Nitre, prepared with Oil of Yixrioly Cloves and 
 and putting it into a clean and dry four Ounce f 
 Gaily- Pot, we fet it under a Chimney; then 
 immediately, and at once, poured to it a Dram 
 
 of the true efiential Oil of Indian Cloves ; and 
 there was inftantly produced a loud Noife, a 
 violent Conflict and Ebullition, with a confide- 
 rable Flame ; which being extinguifhed, a refi- 
 nous Subftance, or adlual Rofin, was found at 
 the Bottom of the Gally-Pot. 
 
 29. To render this Experiment fafe, (i) it Cautions. 
 ought to be performed under a Chimney that 
 
 may carry up the offenfive Vapour ; (2) the 
 Oil ihould be poured from a Phial fixed at the 
 end of a Stick, to prevent any of the fiery Mat- 
 ter from flying upon the Operator ; And to 
 render it fuccefsful, (i) the Spirit of Nitre 
 fhould be ftrong, and frefli drawn ; (2) the 
 Oil fhould be genuine ; ("3) the VefiTel wherein 
 tjie Mixture is made lliould be perfefUy clean, 
 dry, and large enough to give the Matter room 
 to fweli; (4) the Oil fhould be poured in at 
 once, to make the more expeditious Mixture. 
 
 30. This Experiment is neither confined to Extended, 
 one certain Oil, nor to one certain Acid ; the 
 diftilled Oil of SafTafras, Guajacum, Box, Ja^ 
 maica Pepper, Cinnamon, or even the empyreu- 
 matic Oils of Hartfhorn, Blood, ^c. will ferve 
 
 the' Purpofe ; or, in general, any thin,. efTential 
 Oil, thickened with Balfam of Sulphur, i^c. For 
 
428 
 
 And ae> 
 taunted fo 
 
 Its Force 
 in vacuo. 
 
 Lecture the Nineteenth. 
 
 fome Degree of Thicknefs or Tenacity in the Oil 
 feems a primary requifite, to make it explode 
 with Spirit of Nitre ; and for acid Spirits, Oil 
 of Vitriol, and moft of the other acid Spirits 
 highly redlified, will produce Flame with the 
 aromatic Indian Oils, if unadulterated. 
 
 31. The Experiment is made to give the great- 
 er Surprize when Gunpowder is fired by pour- 
 ing a cold Liquor upon it ; for if Gunpowder 
 were put to the Oil, this alfo would be fired, 
 upon pouring in the Spirit of Nitre. Hence it 
 may feem ftrange that Camphire, which is an 
 exceeding inflammable Subftance, fhould not 
 take Fire when added to the Oil, and treated 
 as the Gunpowder. The Reafon feems to be, 
 that Camphire contains an Acid ; and therefore 
 when diflblved in the Oil, fomewhat anticipates 
 or leiTens the Force of the Spirit of Nitre that 
 is afterwards applied •, fo that the Shock betwixt 
 the tv^o is not now great enough to produce 
 Flame : For in the Shock, or violent Conflidt 
 betwixt a ftrong Acid and a thick Oil, divelled 
 of Acid, the Fire and Flame in the Experiment 
 appear to be produced, 
 
 32. Nor is theEffedl leflfened when the Expe- 
 riment is performed in vacuo \ where half a Dram 
 of Oil of Carraway-Seeds, and a Dram of Spirit 
 of Nitre, have made a Flalh like Gunpowder, 
 and burfl: the exhaufled Receiver, a Glafs fix 
 Inches wide, and eight deep *. This is a very 
 extraordinary Effedt *, as differing from moft 
 other flaming Bodies, which rather deftroy than 
 generate Air : But here muft be a large Quan- 
 tity of Air, or fomething of equal Force, gene- 
 rated by the exploding Mixture, in order to 
 balance and over- power the external Preffure ; 
 
 , * Sec Sir Ifaac Ne^vuton's ^eriei at the End of his Optics. 
 
 which 
 
Of Pyrotechny. 429 
 
 which ia this Cafe was feveral hundred Weight. 
 
 Hence it (hould feem that the Force of our explo- 
 five Mixture is much greater than that of Gun- 
 powder; which will not explode in vacuo^ nor, 
 even with the AlTiftance of the Air, produce any 
 thing like fuch an Effect. It may therefore be 
 worth confidering, whether fo great a Power 
 could not be applied to fome ufeful Purpofe. 
 
 The Mixture might be made cheap, by ufing 
 any of the grofs and ponderous empyreumatic 
 Oils, inftead of the eflential Kind. 
 
 Experiment VI. 
 
 ^he liquid Phofphorus of Urine. 
 
 33. We took half a Dram of Camphire, Solid Phof 
 
 ground it in a Glafs Mortar, with three Grains 
 
 of the folid Phofphorus of Urine; then added 
 much effential Oil of Cloves as ferved to reduce 
 the v/hole to a fluid Form. The Mixture thus 
 made may be rubbed upon the Cloaths, the 
 Hair, or the Hands, without Danger of burn- 
 ing a). 
 
 34. Chemiflry hath fcarce afforded any Thing Hiflory of 
 more furprizing than the common Phofphorus, Pho/pho- 
 To fee Letters traced with this Matter become 
 luminous in the dark, Images and the Bodies of 
 
 Men to blaze with Light, and Abundance of the 
 like Experiments performed by Means of Phof- 
 phorus,, made many Perfons curious to know how 
 it was made^). The Preparation indeed feems 
 even to this Day kept as a gainful Secret in few 
 Hands, and the Matter is fold at a very great 
 Price ; Whence we apprehend it would be of 
 
 a) See below under § 43. No. ii. 
 
 h) Sec M. Homberg% Papers on the Subject. 
 
 Angular 
 
430 Lecture the Nineteenth. 
 
 fingiilar Service to Chemiftry, to render this 
 Commodity cheaper, and difcover its farther 
 Ufes. 
 
 35. With this view we fhall here touch a 
 little upon the Hiftory of this Phofphorus^ com- 
 monly called KunckelPs Phofphorus^ or the Phof- 
 phorus of Urine. It was difcovered by accident : 
 One Brandy an obfcure Chemift of Hamburgh^ 
 ftumbled upon it as he was fearching .after the 
 Philofophers Stone, which he firmly believed 
 lay concealed in Urine. This Subjed therefore 
 he tortured a thoufand Ways j and at length, 
 after a violent Diftillation, found a fhining Mat- 
 ter, fince called Phofphorus^ in his Receiver. 
 This Matter was fhewn to Dr. Kunckell ; but 
 the Procefs was concealed from him. Soon af- 
 ter this Brand died *, and Kunckell refledling that 
 Brand worked wholly upon Urine, he continued 
 to work upon the fame Subjedl himfelf for four 
 years together ; and at length, in the year 
 1679, found the Thing he fought after. Dodlor 
 Kraft has ufually pall for the Inventor of this 
 Phofphorus^ he being the firft that carried it 
 abroad : but he only diftributed it for Dr. 
 Kunckell^ being at that Time unacquainted with 
 the Preparation. 
 
 (fhe [olid 3 ^* The fuccefsful Method of making it is 
 Phofpho- this : Evaporate any Quantity of frefh Urine 
 rus, ho^ over a gentle Fire, to a black, and almofl dry, 
 made. Subftance *, then with two Pounds thereof tho- 
 roughly mix twice its Weight of fine Sand; put 
 the Mixture into a ftrong coated Retort of 
 Stone ; and, having poured a Quart or two of 
 clear Water into a large Receiver with a long 
 Neck, join it to the Retort, and work in a na- 
 ked Fire ; let the Heat be fmall for the two firfl 
 Hours •, then increafe it gradually to the utmoft 
 Violence : and thus continue for three or four 
 
 Hours 
 
Of Pyrotechny. ' 
 
 Hours fucceffively. At the Expiration of that 
 time there will pafs into the Receiver a little 
 Phlegm and volatile Salt, much black fetid Oil, 
 and laftly the Matter of xht Phofphorus in Form of 
 white Clouds, which will either ftick to the Sides 
 of the Receiver like a fine yellow Skin, or fall 
 to the Bottom in Form of a fmall Sand. Now 
 let the Fire go out ; but take not away the 
 Receiver before it is cold, for fear of fctting the 
 Phoffhorus on fire, by admitting the Air. To 
 reduce thefe fmall Grains into one Piece» put 
 them into a little Tin Ingot-Mould, along with 
 fome Water; heat the Ingot, to make the Grains ’ 
 melt together; then add cold Water, till the 
 Matter is congealed into one folid Stick, like 
 Bees- Wax ; which being cut into little Pieces 
 fit to enter the Mouth of a Phial, may be pre- 
 ferved by Water, and by keeping the Glafs clofe 
 (topped. If the Glafs be not kept (lopped, the 
 Phofphorus will turn black on its Surface, and 
 at length be fpoiled. 
 
 37. The Cautions required to make the Pro- Cautions. 
 cefs fucceed are, (i) to evaporate the Urine, 
 while it is recent ; (2) to prevent its boiling 
 over, and fo lofing the moft un( 5 luous Part ; 
 
 (3) to let the Matter afterwards Ferment in the 
 cold : (4) to mix the black Matter with Sand, 
 to prevent its melting and running together ; 
 
 (5) to ufe a Stone Retort, thofe of Earth being 
 too porous, and fuffering the Phojphorus to tran- 
 fude fooner than pafs into the Receiver; (6) to 
 have the Receiver very large, and with a very 
 long neck, to prevent its breaking and over- 
 heating, which would either evaporate the white 
 Vapour wherein the Phofphorus confifts, or elfe 
 prevent its coagulating; (7) to put Water into 
 the Receiver, for keeping it cool, and quench- 
 ing the 'Phofphorus^ as it falls to the Bottom ; 
 
 (8) to 
 
432 Lecture the Nineteenth. 
 
 (8) to make the Fire fmall at firfl, that the Re- 
 tort may be preferved, and the black Matter 
 gradually dried, which would otherwife fwell, 
 and come over in a black Froth ; Laftly^ it is 
 tound necelTary, that the Urine for the Opera- 
 tion be of fuch as ufe Malt-Liquors, rather 
 than Wine. All thefe Circumftanccs being re- 
 quired for obtaining the Phofphcrus to advantage, 
 no wonder if fo many have mifearried in their 
 Attempts to make it. 
 
 qheProcefs 3^* This Operation may be greatly fhorten- 
 
 Jf^ortened. cd, by freezing and concentrating frefh Urine, 
 afterwards evaporating it with care, and then di- 
 gefting Viper fe in the Manner above mentioned. 
 When thoroughly digefted, commit the Matter, 
 in a large Quantity, to an Iron Pot, with an 
 earthen Flead, as the Chemifts ufually do for 
 making Spirits of Hartfhorn, or the Spirit and 
 Salt of Urine. When all the Salt and Oil are 
 thus obtained, let the Caput mortuum be taken 
 out, and mixed with twice its own Weight of 
 Alum. This Matter may now be put into a 
 well coated Long-Neck, and worked with care 
 in a Reverberatory- Furnace, into very large 
 Receivers, filled with Water, and connected to 
 the Long-Necks by Adopters ; the lower Ends 
 whereof fhould enter the Water, as in diffilling 
 Quickfilver, and the Operation be continued 
 for eight or ten Flours. And this we apprehend 
 to be the beft Way hitherto known of procuring 
 Phofphorus to Advantage. Dr. TVall informs us 
 that Mr. Boyle^ concerned to find how fmall 
 a Proportion of Phofphorus was afforded by 
 Urine, defired him to look out for another Sub- 
 je6t that might afford it in greater Plenty. The 
 Dodfor afterwards caufing a Piece of dry Matter 
 to be dug up in the Fields where Night-men 
 emptied their Carts, he obferved a great Num- 
 
of Pyrotechny. 433 
 
 ber of fmall Particles of Pbofphorus therein. 
 
 This Matter the Dodlor immediately carried to 
 Mr. Boyle^ who let Bilgar the Chemift to work 
 upon it : But lie could obtain very little Phof- 
 fhorus from it, till another Material was added 
 thereto in Diftiilation *, and then he procured 
 Pbofphorus in fuch plenty that, felling large Quan- 
 tities at fix Guineas the Ounce, he foon became 
 rich and left England The Matter which 
 thus fixes and increafes the Pbofphorus^ we appre- 
 hend to be Alum •, which is itfelf not only in 
 fome Meafure prepared from Urine, but appears 
 to afford the fame Kind of Acid that Pbofphorus 
 yields by burning. For upon its Analyfis, Phof- 
 phorus appears to be a Compofuion of a ftrong 
 Acid and an inflammable Matter united > exadUy in 
 the Manner of common Brimilone \ whence it may 
 not improperly be called an animal Sulphur : 
 
 And accordingly, like common Brimftone, it will 
 burn under a Glafs Bell, and afford Flowers 
 which, by attrading the moifture of the Air, be- 
 come an acid Liquor like Oleum Sulpburis per 
 Campanam. 
 
 39. And in this Manner it has been ufed, fo as Fart¥^ 
 to produce extraordinary Changes upon Metals^ 
 efpecially in the philofophical View ; the Acid ic- 
 felf, even without Heat, proving a Menffruum 
 to perhaps ail ti>e Metals. But w^hen this Acid 
 is driven into the Pores of the Metal, by the 
 Adion of the Flame in burning the PhofpboruSy 
 it feems produdive of much greater Effeds •, as 
 is known to chofe acquainted with the fublimer 
 Metallurgy. And it is principally with a View 
 of promoting this Kind of Experiments, that we 
 have beftowed fo much of our Ledure upon fa- 
 cilitating the Method, and eaflng the Expenccj» . 
 
 See the Pkilofa^hicalTranfaSiions* 
 
 F of 
 
434 - Lecture the Nineteenth. 
 
 of preparing this Phofphorus % which of all the 
 Kinds hitherto difcovered Teems the moft ufeful. 
 Ciher 40. This Phofphorus has been feveral Ways dif- 
 kinds of ^ guifed, To as to make it appear under various 
 PLuiphon.pQj-ppjg . fometimes as a Solid, fometimes as a 
 Liquid, fometimes as an Ointment, fometimes 
 as a running Mercury. There are alfo others 
 of different Kinds j of which we fhall only men- 
 tion two, both difcovered by M. Homherg, The 
 The black is that ufually called the Black Phofphorus^ 
 now commonly prepared with Alum and Wheat 
 Flower, by taking four or five Parts of Alum to 
 one of Wheat Flower, and calcining them toge- 
 ther to a brown or blackilh Mafs ; which being 
 powdered, is put into a Phial, loofely flopped 
 with Paper, and fet in a Sand-Heat, fo as to 
 continue glowing hot for Tome time; then the 
 whole is removed from the Fire, fuffered to cool 
 gradually, and at lafl: the Bottle is flopped clofe. 
 A little of this Powder being poured out of 
 the Bottle, and cxpofed to the open Air, imme- 
 diately takes Fire, and appears like a glowing 
 Coal. But the Powder muft be frefli made, to 
 have a ftrong Effedt ; for the Sun’s Rays, or the 
 Moifture of the Air, being gradually admitted 
 to it, deftroy its Virtue : whence it ought to be 
 kept in a dark and dry Place. ’Tis remarkable 
 of this Phofphorus y that it may be made from 
 almoftany animal or vegetable Subftance, inflcad 
 of V/heat Flower j but that no Salt whatever can 
 be fubftituted inftead of Alum. 
 
 ^The Phof 41. M. Homherg^s other Phofphorus is made of 
 px'rus^cf Sal-Ammoniac, and two Parts Lime 
 
 in the Air •, thefe being mixed well toge- 
 Ime. ther, a Crucible is to be filled with them, and 
 fet in a fmall Fire of Fufion ; where, as foon as 
 the Crucible becomes red hot, the Mixture will 
 melt, and fhould be ftirred with an Iron Rod, 
 
 to 
 
Of Pyrotechny. 435 
 
 to prevent its running over. When the Matter 
 is entirely fufed, it may be poured into a Brafs 
 Mortar ; and when cold it will appear of a grey 
 Colour, and almoft as if it were vitrified. If 
 now it be ftruck with any hard Body, it ap- 
 pears as on Fire in the whole Extent of the 
 Stroke \ but the Matter being brittle, it may be 
 proper for the Experiment’s fake, to dip little 
 Bars of Iron, or Copper, into the melted Matter 
 in the Crucible *, for thus they will be enamelled, 
 as it were, with the Matter ; and thefe Bars may 
 be (Iruck upon, fo as commodioufly to repeat the 
 Experiment feveral Times before the Matter falls 
 off. The Bars are to be kept in a dry Place, 
 to prevent the Phofphorus upon them from run- 
 ning by the Moifture of the Air. 
 
 42. Both thefe Phofphori^ were difcovered by DiCcovery 
 Accident : The firft was obtained by fearching 
 
 fora limpid Oil, from the common ftercoraceous 
 Matter, that fhould fix Quickfilver ; and the fe- 
 cond, by endeavouring to calcine Sal-Ammoniac 
 v/ith Lime, fo as to render it fufible like Wax j 
 which end was obtained, but not the other. 
 
 43. There have been no very confiderable Ufes 
 of thefe two Phofphori hitherto difcovered j but 
 the Phofphorus of Urine has been employed for 
 making many curious Experiments ; a few where- 
 of we fhall here exhibit. 
 
 (1) The Light of this Phofphorus appears great- Exprri- 
 er in vacuo than in the open Air. 
 
 (2) In hot weather it is obferved to dart Flafhes 
 
 of Light through the Water wherein it is con- o^ Vnne. 
 tained, fo as exadcly to refemble Lightning ; which 
 thus darts unextinguifhed through watery Clouds 
 and Vapours. 
 
 (3) Thefe 
 
 F f 2 
 
436 Lecture the Nineteenth. 
 
 (3) Thefe Flafhes of Light are not apt to 
 kindie or burn any combuftibie Matter, in which 
 they refemble the harmlefs Kind of Lightning-, 
 but in a condenfed State this Phofphorus burns 
 very furioufly, and with a moft penetrating 
 Fire, fo as to melt and difTolve Metals : In 
 which refpe(!?l it again refembles the more de- 
 llrudive Kinds of Lightning, which are found 
 to have the fame EfFeds. 
 
 (4) If a little Piece of this Phofphorus be view- 
 ed through a Microfcope, the internal Parts ap- 
 pear in a conftant Ebullition. 
 
 (5J A little Piece of it being put into a Silver 
 Spoon, and held over the Fire, it burfts out 
 into a Alining Flame, leaving a red fpot in the 
 Spoon of a corrofive, acid tafte; which being 
 diluted with Water, the Mixture makes a con- 
 Aid with Oil of Tartar per deliquium, 
 
 (6) If a little of it be ground in a Glafs Mor- 
 tar, with twenty times its own Weight of 
 Nitre, it does not take Flame, but only difperfe 
 a Alining Property through the Body of the 
 Nitre ; but if ground in the fame Manner with 
 Iron^Filings, reduced to Powder, a bright Flame 
 immediately enfues. 
 
 (7) Though this Phofphorus appears to be a 
 Kind of Sulphur; yet it does not difTolve in 
 high redified Spirit of Wine, but communicates 
 fome lulphurecus Parts thereto; For if this Spi- 
 rit be poured to Water in the dark, it yields a 
 faint Des;ree of Liyht. 
 
 (8) The Nature of this Phofphorus is confide- 
 rably changed, by being long digeAed with Al- 
 cohol : For rhus it becomes a Kind of white 
 tranfparent Od, rhnt does not coagulate v/ith- 
 our an extreme Degree of cold, nor afford any 
 Manner of Light ; and when freAi Spirit of 
 
 Wine 
 
437 
 
 of Pyrotechny. 
 
 Wine is poured thereon, it does not like other 
 Oils, mix therewith, nor difTolve therein. 
 
 (9) If this Phofphonis be feparated from the 
 .Spirit of Wine wherewith it was digefted, and 
 be afterwards w’ell wafhed in common Water, 
 it, by Degrees, recovers its former Confidence, 
 and coagulates into a tranfparent Matter, whiter 
 than before ; but neither affords fo much Light, 
 nor recovers its primitive fhining Virtue, nor 
 its yellow Colour. 
 
 (10) The Spirit of Wine fo feparated be- 
 comes yellowifh, and fmells ftrong of the Phof- 
 pborus ; though it ihines nof^ except when poured 
 upon Water. 
 
 (11) This Phofphoius being mixed with a large 
 Quantity of Pomatum, makes, as well as with 
 Camphire and the Oil of Cloves, a fliining Un- 
 guent, that may be rubbed on the Hands and 
 Face, without Danger of burning, lo as to ren- 
 der them luminous in the Dark. 
 
 (12) If a Piece of Paper, or Linen, be dipt 
 at one End in Spirit of Wine, and a Bit Phof- 
 phorus be crulhed on the other End that remains 
 dry, the Spirit will be fired by the Phofphorus^ 
 wirhouc immediate Contadf : But the fame Thing 
 will not happen, if the Paper were dipt in Oil 
 of Turpentine, nor if a Bit of Phofphonis were 
 rubbed upon the End dipt in the Spirit of 
 Wine; only when the Spirit is entirely evapora- 
 ted the Phofphorus will burn, though with Diffi- 
 culty, and ilowly. 
 
 44. There are many of thefe odd Kind of 
 Experiments that might be made with Phofpho- 
 rus ; which is a Subftance that feems, in Che- 
 miftry, to be much fach a Thing as the Load (lone 
 in Natural Philofophy ; and itseffedls arealmoftas 
 odd and difficult to explain, for want of knowing 
 the latent Properties of Bodies. 
 
 F f 3 Axioms 
 
438 Lecture the Nineteenth. 
 
 Axioms and Canons. 
 
 1, We learn from the preceding Experiments, 
 That Gunpowder, and the Arts thereon depend- 
 ing, are capable of farther Improvement *, and 
 that more forcible and dedrudive Inventions, 
 than thofe at prefent in Ufe, are difcoverable, if 
 required a ), 
 
 2, Thar, in particular, great Ufe may be 
 made of comprefTed Air in this Way, the Mix- 
 ture of Iron-Filings and Brimftone, in large 
 quantities-, the Pulvis ?Lnd Aurum fidminans \ Salt 
 of Tartar ; the Mixture of certain cheap Oils 
 and acid Spirits, for producing extremely pow- 
 erful and dedrudive Efieds h). 
 
 3. That many natural Ph^enomena, fuch as 
 Earthquakes, Thunder, Lightning, Vulcanos, the 
 Aurora Borealis, Hot Baths, are imitable and 
 explicable by chemical Experiments, particular 
 Mixtures, and explofive Powers c). 
 
 4. That Fire and Flame are producible by 
 the fimple Mixture of appropriated Bodies, if 
 made with fufBcient Violence : or that Oils freed 
 of their acid Part, and fuddenly joined with 
 Ilrong acid Spirits, are inflantaneoufly produc- 
 tive of Fire and Flame d). 
 
 5. That by this Adion, or the intimate and 
 flrong Union of acid Spirits with Oils, Rofins 
 are producible d ). 
 
 6. That very violent Fxplofions may be made 
 in vacuo j as well as in the open Air d). 
 
 7. That the Phofphorus of Urine is applicable 
 to many extraordinary Purpofes; particularly to 
 the introducing of uncommon Changes in metal- 
 line Bodies e). 
 
 See Exp. I. II. and V, b) Exp. I. II. III. V. Exp. 
 m. IV, V, VI. Exp. V. ej Exp. VJ. 
 
 8. That 
 
439 
 
 Of Pyrotechny. 
 
 8 . That as moft Difcoveries of chemical Ex- 
 plofions and Pbofphori were accidental, greater 
 Things may be expcdled from a fagacious Expe- 
 rience, conduded by Keaibn, and by a farther 
 Difcovery of Caufes and Axioms a), 
 
 9. That the Phofphorus of Urine rhay be made 
 in large Quantities, and with fmall Expence •, fo 
 as to afford defirable Opportunities for the farther 
 Improvement of Chemiftry and Metallurgy b), 
 
 10. That there may be many latent Eroperties 
 in Bodies, remaining unknown to us, for Want 
 of making the proper Experiments *, which alone 
 can difeover, and bring thofe Properties to light <3^, 
 
 a') See Exp. I. II. Ill IV, V. VI. 
 
 £>) Exp. VI. 
 
 F f 4 
 
 L E C- 
 
[ 440 ] 
 
 LECTURE XX, 
 
 CONTAINING 
 
 Ways of applying Chemiftry to the farther 
 Service and Improvement of Natural Phi^ 
 lofophy, Arts, Trades, and Buiinefs. 
 
 I. 
 
 prefent Lecture is intended to fbew 
 I j Tome particular Ways of extending and 
 applying Chcmiftry to the farther Im- 
 provement of Natural Philofophy, Arts, Trades, 
 and Manufadlures. For though this be the ge- 
 neral Defign of our whole Courfe, yet we judge 
 it proper to bellow our Uft Lc( 5 lure exprefsly upon 
 the Subje6t. We fhall therefore (i) divide 
 Chemiftry into its feveral Branches, and fhew how 
 each of them may be farther improved ; (2) exhi- 
 bit a fet of Experiments tending to that End ; 
 and (3) offer a few Rules for its farther Appli- 
 tion and Enlargement. 
 
 Chemijlry 2. Chemtfiry^ m general, may be ufefully di- 
 dinjided^ vided into Philofophical, Technical, Commercial, 
 and Oeconomical Chemiftry. 
 
 Into Philo- 3. By Philofophical Chemiflry we underftand 
 jophical, Chemiftry pradlifed in Miniature, after the Man- 
 ner of our prefent Courfe*, fo as to find out the 
 Caufes of phylical Effeds, and to make new 
 Difeoveries in Nature *, 
 
 4. By 
 
 * See below § 7. 
 
Commer- 
 
 cial, 
 
 And OccQ' 
 nomicaL 
 
 Philo Tophi • 
 cal Che- 
 mijiry ; 
 its Parts ; 
 
 of Enlarging Chemijlry^ &c. 441 
 
 4. By Technical Chemijiry we under ftand t\it^echnical. 
 Application of Philofophical Chemiffry to the 
 immediate Service of fome Art*, fo as to invent, 
 form, afTift, promote, or perfedt it in the large 
 Way of Bufinefs. 
 
 5 By Commercial Chemijiry we mean the Appli- 
 cation both of Philofophical and Technical Che- 
 miftry to the eftablifhing, fupporting, and improv- 
 ing any Branch of Trade or Commerce. 
 
 6. And by Oeconomical Chemijiry we mean the 
 Application of Philofophical, Technical, and Com- 
 mercial Chemiftry to the Service and Accommo- 
 dation of a Family. 
 
 7. Philofophical Chemiftry confifts of three 
 Parts ; viz Invention^ Rationale^ and Experiment : 
 
 Whence we may define it a particular Exer- 
 cife of the rational and inventive Faculties of 
 the Mind, leading to Experiments, and thence 
 to the Difcovery of Caufes ; fo as to form 
 Axioms, that (hall rationally Account for Phae- 
 nomena, and difcover Rules of Praclice for pro- 
 ducing ufeful EfFeds. And thus Philofophical 
 Chemiftry is not only a Key to all the other 
 Parts, but of itfelf difcovers the Caufes of ma- 
 ny natural Phaenomena ; as particularly Earth- 
 quakes, Volcanos, Vegetation, the growth of 
 Minerals fsfr. 
 
 8. This Branch of Chemiftry alfo explains the //i 
 general Forms and Qualities of Bodies, whereon , 
 their Properties and EfFedls depend *, as Volatility 
 and Fixednefs, Fluidity and Firmnefs, Colours, 
 
 Taftes, Odours, Effervefcences, Fermentation, 
 
 Solution, Precipitation, Congelation, Extradion, 
 and the like. 
 
 9. To this Part of Chemiftry it likewife be- 
 longs to bring new Inventions to the Teft, fo as 
 to difcover their Validity or Infufficiency. Thus 
 when any Hint is ftarted for a new Trade, or 
 
 Method 
 
442 Lecture the Twentieth. 
 
 Method invented for the Improvement of an old 
 one, before any Attempt is made to apply it in 
 the larger Way, the proper Aflay or Experiment 
 muft firit be performed in Miniature; where if 
 it prove fuccefsful, this may rationally encourage 
 the eredting of fuch a Difcovery into an Art, or its 
 Application to the Improvement of Bufinel^. 
 llufirateL jq. To have an Example of this whole Pro- 
 cedure, we need but refled upon the general Office 
 of the AfHiy Mafter ; who before-hand difcover?, 
 in Miniature, the Quantity of Metal contained 
 in any Ore affigned ; thereby giving a Diredlion 
 to the Operator at the larger Furnace. And thus 
 Phiiofophical Chemiftry plays dire£lly into the 
 Hands of the Technical, Commercial, and Oeco- 
 r.omical Species, 
 
 Jislm- II. But before it can do this to the beft Ad- 
 vantage, there are feveral Deficiencies therein that 
 Ijrfort- j-equire to be fupplied: And firfl:, the Labour, 
 raiory. Lxpence nccdlary to procure the 
 
 proper Furnaces, VefTels, Utenfils, and Subjedts, 
 for the ready and commodious Exercife of this 
 Art, have been a great Hindi ance to its Advance- 
 ment. Upon which Confideration we have en- 
 deavoured to colledl together a commodious Phi-^ 
 lofophical Laboratory in a portable Form attended 
 with as many Conveniencies as the Nature of the 
 Thing will allow a ). 
 
 Bypraai- i2. In our Definition of Chemiftry b)^ we en- 
 deavoured to avoid the common Error of con- 
 fining this Art to the foie Ufe and Application of 
 Furnace, Fhe. We liDpe to have fhewn c) that it has a 
 Right to employ the other Elements, Air, Wa- 
 ter, and Earth ; to which we may add Cold, 
 
 a) See the Filay for introducing a Portable Laboratory. 
 
 h) lea, 1. in inii. 
 
 0 lea, 1. II, III, IV. 
 
 and 
 
4+3 
 
 Of Enlarging Chemijlry^ See. 
 
 and various Kinds of Motion. And if it be re- 
 membered, that Chemiftry is the Art of analy- 
 fing and compounding Bodies by Means of all 
 the Inftruments we can procure , an Attempt to 
 introduce Ways of working in the Art, without 
 Fire or Furnace, will not appear furprizing. 
 
 13. Nay, if a due Eftimate were made, znd Par/uu- 
 the full Scope and Extent of Chemiftry confi- 
 dered ; a large and curious Part of it would ap- 
 
 •pear to depend more upon other Things, than 
 upon the direct Ufe of Fire: Thus for Example, 
 the whole of Fermentation and Putrefadion, 
 two Extenfive Operations in Nature and Art, 
 are performable without the Ufe of either Fire 
 or Furnace. Farther, the Adion or inftrumental 
 Efficacy of Air, Water, and Earth might, with 
 regard to chemical Operations, be oppofed to 
 the Adion of Fire ; which has ftill a more dired 
 Antagonift, or rather Correlative, viz. Cold ; 
 whofe Efficacy in Chemiftry is extremely great, 
 and feparates the more ufelefs and aqueous Parts 
 of Bodies from thofe that are more fpirituous 
 and eflential *, as we fee in the Concentration of 
 Wines, Vinegars, and other fpirituous and faline 
 Liquors by Froft 
 
 14. There is farther wanting to the Improve- 
 ment of Philofophical Chemiftry^ a Colledion 
 
 all that is hitherto known and pradifed in the uaingthe 
 Art, to ftiew the prefent State and Condition Experi- 
 thereof. And this, perhaps, would make no very 
 large Volume *, for the original Experimental 
 Writers are very few, in Comparifon of the Col- 
 ledors and Tranferibers : But the more ufeful 
 Part of fuch a Work is not to be found in Books*, 
 and can be had only from obferving, colleding, 
 
 * See the laft of three EfTays in Artificial Philofophy, or 
 Univerfal Chemiftry, Ann. I’jii. 
 
 and 
 
444 ^ 
 
 AUflof 
 
 Dclldera- 
 
 ta. 
 
 technical 
 
 Chemijiry 
 
 divided. 
 
 Lecture the Nineteenth. 
 
 and digefting the daily Praftices of mechani- 
 cal Operators *, fuch as Refiners, A flay -M afters. 
 Smelters, Dyers, Sugar - Bakers, Soap - boylers, 
 Csff, And till the Secrets and Myfteries of thefe 
 Arts are known to the chemical Philofopher, he 
 will want many things that are neceflarily re- 
 quired to the Improvement of Philofophicaj. 
 Chemiftry. 
 
 15. The laft particular we dial] at prefent in- 
 timate, as wanting for the Exercife and Improve- 
 ment of Philofophical Chemiftry, is a Lift of the 
 Chemical Defiderata in all Arts and Trades, in 
 order to procure the readieft Ways of fupplying 
 them : For fuch a Lift would contain fo many 
 Problems for the Philofophical Chemift to folve. 
 
 16. We now proceed to technical Chemiftry^ 
 
 which, for the Sake of Ufe and Commodioulhefs, 
 we divide into four Parcs : as it relates to Sub- 
 je£ls of the animal, vegetable, and mineral King- 
 doms ; or to feveral of them at once. Thus 
 under animal Arts comes the Arc of preparing 
 Size and Glue, Tanning, Ivory-iStaining, the 
 Dying in Wool, Silk, Cfc. Under vegetable 
 Arts comes the Art of Timber, or the Ways of 
 preferving it found againft the Injuries of the 
 Weather, the Sea, Cfr. the Art of making 
 Rofin, Pitch, Oil of Turpentine, Charcoal, Poc- 
 Afh, Cfc. the Art of Brewing, and Fermenting 
 for Wines, Vinegars, the Art of Sugar- 
 
 making, and Refining-, the Art of Soap-mak- 
 ing, ^c. Under mineral Arts come the Arts of 
 Salt, Copperas, Vitriol, Borax, Pottery, Metals, 
 Foundery, Smithery, And laftly, under 
 
 mixed Arts comes the Art of Paper, the Art of 
 Ink, the Art of Japanning, the Art of Glafs, 
 the Art of Pigments, the Art of Pharmacy, 
 the Arc of Fire* Works, fcfc. all which are 
 
 proper 
 
of Enlarging Chemijlry, &c. 445 
 
 proper chemical Arts, that fall under Technical 
 Chernillry. 
 
 17. It were eafy to give a Catalogue of a large Hcnfftoh 
 Number of new, and probably advantageous, improved. 
 Arts or Trades, that might be fet up in Eng- 
 
 land. Thus, for inllance, we would recommend 
 the Introdudion of Englijh Arracks and Bran- 
 dies which might be plentifully afforded by 
 the Tappings of our Trees, and all Kinds of 
 Summer-Fruits : Nor need Wines themfelves, 
 even from the Grape, be here excepted ; efpe- 
 cially as we have an excellent Method of improv- 
 ing all poor and thin Whines, by adding fine fla- 
 vourlels Sugar in the Fermentation 
 
 18. We have endeavoured to fliew, in the 
 
 preceding Ledtures, that many of our Trades are 
 improveable ; particularly Brewing, DiftilJing, 
 Soap-boiling, Pharmacy, Metallurgy, And 
 
 for new Trades, that the refining and making of 
 various Commodities may be as advantageoufly 
 pradlifed in England as elfe where ; And among 
 thefe may be reckoned the refining of Borax, 
 Camphire, Tartar, Manna, the making of 
 Salt-Petre, the obtaining of Sulphur, the mak- 
 ing of blue Vitriol, Porcellane, artificial Gems, 
 and numerous ocher Commodities of Price and 
 Ule. 
 
 19. The great thing wanting to the Advance- 
 ment of Arts, and the Perfedlion of this whole 
 Affair, feems to be the joint Concurrence of cer- 
 tain Perfons, who fhouid contribute to the car- 
 rying it on. The Compafs of Knowledge al- 
 lotted to a fingle Man or two, bears no Propor- 
 tion to that required for the due condudting of 
 this Work: Nor, perhaps, is the Knowledge in 
 being, of the Kind here principally required. 
 
 f See lea, XI. 
 
 Arts 
 
446 
 
 Commer-- 
 dal Che- 
 mijlry di- 
 
 ^ided. 
 
 Lecture the Twentieth. 
 
 Arts and Sciences muft receive their Improve- 
 ments chiefly from Phyjlcal Knowledge % that is, a 
 Knowledge drawn from the Nature of Things, 
 which is to be acquired only by converfing with 
 natural Bodies, and obferving their Properties, by 
 putting Bodies together, and feparating them a- 
 gain. And this general Procefs is to be conduc- 
 ed in the way of a fagacious Experience \ which 
 is a Matter of Judgment, not cafual or accidental 
 but formed upon fome certain Principles and 
 Analogy of Knowledge. Thus we fee, in ordi- 
 nary Life, and the PraCice of Trades, that Men 
 educated to them have an acquired Sagacity, or 
 Habit of judging each in his own way ; which Sa- 
 gacity is rarely to be found in Men differently edu- 
 cated. The Qualifications therefore required for 
 our prefent purpofe may be termed, Phy fecal or 
 Chemical Habits of judging about Things relating 
 to Arts and Trades^ acquired by fome competent 
 Experience, or by being for fome Time vcrfed 
 in this Way. 
 
 20 If Choice were made of a Set of Men fo 
 qualified, and Rules given them to purfue, with 
 due Care to rcgifler all their Experiments, and 
 form them into Tables^ from whence fome fhould 
 derive Canons and Axioms, others deduce the 
 more ufeful Things for the Service of Arts and 
 Trades Cfr. So as to make an uniform and 
 Ready Bufinefs of the whole ; there is good Rea- 
 fon to expeC that, in the compafs of a few Years, 
 confideratDle Improvements might be made in the 
 prefent of Arts and Sciences. 
 
 2 1. Commercial con fiRs of three parts > 
 
 noiz. {i) The Exercife of all the Chemical Arts, 
 in a large Manner ^ fo as to fupply more than 
 the Den; anus of a fingle Country, and afford a 
 Surplus of Commodities for Exportation and fo- 
 reign Confumpeion ; (2) The various Ways of 
 
 con- 
 
Of Enlarging Chemifry^ &c. 447 
 
 condenfing, curing, preparing, fecuring, and fit- 
 ting natural and artificial Commodities for Car- 
 riage and Tranfportation ; And (3) the Ways of 
 fupplying the chemical Neceflaries to Voyagers 
 and Travellers, for founding, fupporting, and im- 
 proving Trade, Traffic, and Commerce, in dif- 
 ferent Countries. 
 
 22. And thus a Knowledge of Commercial Che- Howoteh 
 mtfiry will eafily diredt us in England^ to the 
 
 Arts that may be extended and improved, fo as to 
 underfell fomc other Nations at the foreign Mar- 
 kets j provided the Duties and Drawbacks are 
 in our Favour ; For example *, We conceive, that 
 Malt-Spirit may be produced in England cheaper 
 and better than in Holland \ that Wines, Vine- 
 gars, Brandies, and Arracks, may be made, either 
 here, or in our Plantations, as good as, and per- 
 haps cheaper than, in their prefent places of growth 
 and Importation *, that White Lead, Verdigreafe, 
 Sal-Amoniac, Pot-Afh, Hard Soap, ^^c. may 
 be prepared as cheap and good in England as in 
 any other Part of Europe. 
 
 23. We arelikewife intruded by Commercial 
 
 Chemijiry^ to reduce Goods to their lead Volume 
 or Bulk for Exportation ; and again to fecure 
 them from the Injuries of the Sea, the Weather, 
 and other Accidents. Thus Metals come to be 
 exported indead of their Ores, Sugars indead of 
 the Juice or Rob of the Sugar-Cane, Salt indead 
 of Sea- Water, Raifins indead of Grapes, high 
 Spirits indead of low Wines, Pot-Afh indead of 
 refufe Wood, And thus it is that, by means 
 
 of Technical and Commercial Chemidry toge- 
 ther, diderent Countries are fupplied with Lead, 
 
 Tin, Iron, Silver, Oil, Tallow, tanned Hydes, 
 
 Pitch, Rofin, Brimdone, Wax, Wines, Brandies, 
 
 Salt, Sugars, Treacle, Paper, Csfr, whereby all 
 
 Trade, 
 
Lecture the Twentieth. 
 
 Trade, Traffic, and Commerce, is fupported. 
 And to difcover this Kind of Contrivance, or 
 Reduction ^ is the Office of Commercial Chemiftry. 
 Thus, inftcad of importing many Tuns of a 
 foreign dying Wood, we are taught to extract 
 its tinging Parcs, and bring them away in the 
 Quantity of a few Pounds. And to do this more 
 generally, as it may be done, would tend to per- 
 fe6t the Trade of the Dry-Salter,, and leflen the 
 Expence of the Dyer. 
 
 24. Another Advantage of Commercial Chemu 
 Jiry is, that it affords the Neceffaries for long 
 trading Voyages. Thus, in particular, it directs 
 us to a Chemical Cheft^ and a Portable Furnace^ 
 with its Apparatus of Flux-Powders, for affaying 
 Ores ; a Screw- Prefs for Oils, and a Still for ex- 
 amining fermented vegetable Juices. It alfo 
 direds us to the certain Rules of difeovering the 
 Sophiftications prad'ifed in Wines, Brandies, Vine- 
 gars, Arracks, Gold-Sand, Gold in Bars or In- 
 gots, counterfeit Gems, (^c. and to the ways of 
 affaying Pot-Affi, Tinea), Amber-greafe, Mufkj 
 and ail other Drugs. So that to improve this 
 Parc of Chemiftry, little more Teems required than 
 the bringing it into more general Ul'e ; w'hich 
 might be done to great Advantage, if Philofo- 
 phical and Technical Chemiftry were im- 
 proved to any confiderable Degree. 
 
 Oeconomi-^ 25. We HOW come to our lad Divifion of 
 Chemiftry, viz, the Oeconomical Branch; which 
 is of great Utility and Extent, fo as to be capable 
 of improving all the reft. This Branch we 
 choofe to divide with regard to the feveral Of- 
 fices of a Houfe, in which, as in fo many dif- 
 ferent Laboratories, it may be commodioufty 
 pradtifed : For Inftance, in the Brewhoufe, the 
 Store - Room, the Kitchen, the Dairy, the 
 Laundry, and the Cellar. Thus, by Means of 
 
 Oecono^- 
 
Of Enlarging Chemtflry^ &c. 449 
 
 Oeconomical Chemifiry^ we are inftruded in the 
 beft Ways of brewing with Malt, Treacle, 
 
 Hony, Sugar, or other vegetable Juices-, the 
 belt Ways of raifing and preferving Yeaft, or 
 Wine Lees, for baking or brewing and of 
 imitating the natural Wines of foreign Growth. 
 
 This Arc direds us how to procure the fimple 
 and compound Waters of Vegetables, in their 
 greateft Perfe6i;ion and to make a Set of Bran- 
 dies or Cordial Waters, even from the grofs 
 Lees, Sediments, or Bottoms of our Wine or 
 Ale Cafks. Hence alfo we learri the Methods 
 of preferving Fruits in Sugar, and feveral vege- 
 table Produdlions in the Way of Pickle,- Lfc. 
 
 The Art of Cookery alfo is by this Means im- 
 proveable : So are all the Dairy Productions, 
 and the Bufinefs of the Laundry as by render- 
 ing hard Waters foft, ^c. But to Ibew this 
 fully, and to improve the Defign, would require 
 a’ particular Treatife, under the feveral Heads 
 of the Brewhoufe^ the Store-Room^ the Kitchen^ 
 the Dairy ^ the Laundry^ and the Cellar 
 
 II. 
 
 » 
 
 26. We now proceed to our Experiments ^ Purf-.ort of 
 the Jirft whereof will fhew that Sal-Ammoniac 
 may probably be made to as great Advantage in 
 England as in the Levant the fecond will fhew 
 the Method of making a Varnifli of Amber, 
 with a View to improve the Arts of Japanning, 
 Embalming, the third will fhew how to 
 make a very hard Glafs, for improving the Art 
 of Glafs, Enamelling, and the Bufinefs of arti- 
 ficial Gems ; the fourth will fliew^ how to pre- 
 pare a Foil for foliating figured GlafTes, and 
 
 * See tlie firft of the three EfTays in Artificial Vhilofophyy 
 cr Vniverfal Chemifiry^ publiihed in 1731. 
 
 g 
 
 turning 
 
450 Lecture THE Twentieth. 
 
 turning them into Speculums ; the fifth will 
 fliew a Way of making a curious and ufefui 
 Glue ; and the fi:>cth and laft will fhew a Method 
 of giving Copper a Gold Colour, and a greater 
 Degree of Dudility, by Way of direding an 
 Enquiry after Methods of introducing other ufe- 
 fiil Changes into Metals. 
 
 Experiment I. 
 
 nat Sal-Ammoniac may he advantageoufiy mads 
 in England. 
 
 SalJm- 27. We took four Ounces of the common 
 woniac volatile Salt of Ox-Bone, and faturating it with 
 frepared. drong Spirit of Sea-Salt, evaporated the fii- 
 perhuous Moiilure ; upon which we found a 
 Cake of true Sal-Ammoniac left behind. 
 
 Vfeofth‘> Experiment regards both Philofo- 
 
 Experi - " phlcal and Technical Chemiftry ; as not only 
 inent. Siew’ing that Odours may depend upon the Me- 
 chanical Strudure or Texture of the Parts of 
 Bodies •, but alfo leading to a cheap Way of ob- 
 taining Sal-Ammoniac in other Countries, as 
 v/eil as in the Levant. 
 
 In Fhilofo- 29. The volatile Salt here employed has a 
 phkalChe- quick and pungent Odour; fo likewife, 
 ^ Degree, has the Spirit of Salt : 
 of' thefe two, upon mixing, deftroy each other’s 
 
 Odours. Odour, fo as to leave the Cake of Sal-Ammo- 
 niac fcentlefs. The Reafon is, that thefe two 
 odorous Liquors lofe of their Volatility by Mix- 
 ture; fo that their fine Parts can no longer 
 fly off brifkly, and drike the Nerves of the Nofe, 
 on which all fmelling depends. But if a little of 
 the Sal-Ammoniac be ground in a Mortar, along 
 with another fcentlefs, but more fixed. Body, 
 viz. an equal Quantity of Salt of Tartar ; this 
 
 Salt 
 
Of Enlarging Chemiftry^ 8cc. 451 
 
 Salt of Tartar laying hold of the Acid of the 
 Sea-Salt, leaves the volatile Salt at Liberty to 
 afcend and ftrike the Noftrils as brifl^Iy as be- 
 fore : Whence we fee that Odours may be me- 
 chanically produced and deilroyed. The fame 
 is confirmed by many other Infcances of Phi- 
 lofophical Chemiftry, and holds equally of 
 Tafles. 
 
 30. Hence we may derive fome Rules {qi 'Rules for 
 improving the Odours of certain Perfumes, or 
 
 for recovering them when impaired, or almoft 
 deflroyed. Thus it is known to Perfumers, 
 that Sugar being ground with Muflc or Amber- 
 greafe, opens the Body thereof, and makes 
 thefe Subltances go farther in the perfuming of 
 Waters, Powders, or the like : And this the 
 Sugar does chiefly, by attenuating, refolving, 
 and fubtilizing the vifcous Parts of thofe Sweets, 
 fo that they now move more freely, and itrike 
 the Noflrils more brifkly, than before. And 
 when thefe, or other Perfumes, have almofl loft 
 their natural Odour, it may in good Meafure be 
 recovered by the prudent Addition of a little 
 volatile, animal Salt *, as that of Hartfiiorn. And 
 hence we fee the phyfical Reafon why decayed 
 Perfumes are fometimes fufpended in a Jakes, to 
 recover their loft Odour *, for all fuch Places 
 abound with volatile Salts, continually arifing 
 from the Urine, and other animal and vegetable 
 Matters, v^hich are there in a State of Putre- 
 facftion. 
 
 31. Sal-Ammoniac is alfo obtainable in Eng- 
 land^ by fubliming a Mixture of Wood- Soot, fuoniac 
 Urine, and Sea-Salt but it feems eafler and 
 perhaps it miight prove cheaper, to prepare it 
 
 in the Way of the prefent Experimienc. The 
 volatile Sait for the Purpofe will be abundantly 
 fuppiied by the Pith of Horns, Blood, the Refufe 
 G g 2 of 
 
452 
 
 ‘The Expe- 
 rimc/it ex' 
 tended. 
 
 Amher dij- 
 Jolved,. 
 
 Ufe of the 
 
 Expert- 
 
 ment. 
 
 Lecture the Twentieth. 
 
 of a Slaughter-houfe, putrified Vegetables, 
 and the Spirit of Salt may be made at an eafy 
 Kate, in a proper Furnace. 
 
 32. But the prefent Experiment might prove 
 flill more ferviceable, by leading to a Way of 
 procuring other faline Bodies befides Sal-Am- 
 moniac : For it fhouid feem that feveral Salts 
 may be artificially compofed by the Union of 
 their conftituent Farts ; as we here fee in Sal- 
 Ammoniac. For Example ; the Making of 
 blue Vitriol may be attempted, by boiling Cop- 
 per, inftead of Iron, in the raw Liquor of the 
 Pyrites, from which the common green Vitriol 
 is made. And it this Flint were duly purfued, 
 perhaps it might lead to the Difcovery of feveral 
 new Arts and Trades. 
 
 Experiment II. 
 
 An Amher Varnijh. 
 
 33. W^e took four Ounces of Amber, and 
 putting it into a Crucible, juft melted it with a 
 fmall Degree of Heat ; then poured the fluid 
 Mafs upon the Iron Plate. When the melted 
 Matter grew cold, we reduced it to Powder ; 
 and adding thereto two Ounces of drying Oil, 
 (that is, Linfeed Oil prepared, or thickened, 
 by boiling it with a little Litharge) and one 
 Pint of Oil of Turpentine, we diflTolved the 
 whole together into a Varnifh. 
 
 34. This Method of making the Amber Var- 
 nilh is kept as a Secret in few Hands ; but de- 
 ferves to be made publick, as a leading Experi- 
 ment, to direeft the Means of perfeding the Arts 
 of Varnifhing and Japanning, or the Ways of 
 diflTolving Amber; whereon the Perfeclion of 
 various Arts may depend. Thus, in particular, 
 
 the 
 
Of 'Enlarging Chemifry^ See. 453 . 
 
 the Art of Embalming would be highly impro- 
 ved, if we could preferve the human Corps in 
 a tranfparent Cafe of Amber*, as we fee the 
 ’ Bodies of Flies, Spiders, Gralhoppers, Cfc. are, 
 to great Perfedion. 
 
 35. An ufeful Subftitute, or Approximation, 
 in this Way, has been tried, by boiling fine Rofm 
 to Colophony, or a tranfparent and hard, though 
 brittle, Subftance. This being diflbived by 
 Heat, and the Bodies of fome fmall Animals 
 dipped therein feveral times fucceflively, they 
 have been thus coated over with Colophony ; 
 which in fome Degree refembles Amber, but re- 
 quires to be carefully kept from Duft, in order 
 to preferve its Tranfparency. 
 
 36. But if Amber could be difTolved without U/’^s of ellf- 
 impairing its Tranfparency *, or if one large Mafs 
 
 could be made of it, by uniting a Number 
 fmall ones, it would thus not only tend to per- 
 fed the Art of Embalming, but iikewife come to 
 be ufed, on many Occafions, inftead of Wood, 
 
 Marble, Glafs, Silver, Gold, and other Metals : 
 for then various Kinds of VefTels and Utenfils 
 might be commiodioufly miade thereof. 
 
 37. To forward the Difeovery, our prefentHow/® 
 Experiment fliews, that Amber contains a cer- 
 
 tain flimy, aqueous, or mucilaginous Part, which 
 in the ordinary Way requires to be evaporated 
 by a fcorching Heat, before the Amber will 
 readily diuolve in Oil *, with which however it 
 afterwards unites into a Subftance of a Nature 
 compounded of that of an Oil, a Gum, and a 
 Rofin. Nor would the thin ethereal Oil of Tur- 
 pentine diffolve it, unlefs nrft thickened, and 
 fitted for this Purpofe, by Means of the drying 
 Oil. Hence, as it feems plainly intimated that 
 Amber is not only refinous, but alfo mucilagi- 
 nous, whoever would attempt to melt fmall Pieces 
 
 G g 3 of 
 
45 + 
 
 Borax 
 
 Glafs, 
 
 XJfe of the 
 Experi- 
 ment, 
 
 Lecture the Twentieth. 
 
 of Amber into large ones, would do well to con- 
 fider the Subjed as a mucilaginous Rofin, and 
 confequently (i) fitted todifiblve, in a thick Oil, 
 after a previous Evaporation of its aqueous Parts, 
 or the Deftrudlion of its more mucilaginous Na- 
 ture •, (2) that it may pofTibiy be diflblved, by 
 boiling in a Lixivium of Salt of Tartar, and 
 Qiiicklime ; or if any could be found, as there 
 may, ftill fharper, and more alkaline ; and (3) 
 that the Digeffor fee ms well adapted to dilTol ve 
 this- mucilaginous and refinous Subftance, by 
 Means of an exprelTed Oil added to the Amber, 
 finely povv^dered and kept from fcorching by the 
 Interpofition ot Water. And here we recommend 
 a long and moderate Digeftion, rather than a vio- 
 lent Hear. Thus, therefore, our prefent Expe- 
 riment points out to us three Methods for dif- 
 folving Amber, which either do not confiderably 
 •deffroy its Texture, or at worft leave it in a 
 State reducible, by an eafy Operation, to a Kind 
 of Amber again. 
 
 Experiment III. 
 
 A harder Glafs than the common, 
 
 38. We took four Ounces of Borax, and an 
 Ounce of fine white Sand, reduced to Powder, 
 and melted them together in a large clofe Cru- 
 cible, fet in a Wind Furnace, keeping a ftrong 
 Fdre for half an Hour ; then taking out the Cru- 
 cible, and breaking it when cold, we found at 
 the Bottom a pure hard Glafs, capable of cutting 
 common Glafs almoft as well as a Diamond. 
 
 39. We have here an Experiment, which, be- 
 ing d^ly varied, m.ay lead to fome confiderable 
 Improvements in the Arts of Glafs, Enamels, 
 and artificial Gems : It fhews us an expeditious 
 
 Method 
 
Of Enlarging Chemijlry, &c. 4^^ 
 
 Method of making Glafs, without the Ufe of a 
 fixed Salt; which has generally been thought 
 an effential Ingredient in Glafs, and which is 
 the Ingredient that gives the common Glafs its 
 Softnefs. But Borax is a neutral Salt, which, 
 being urged by the Fire, does not turn any 
 Way alkaline ; but, of itfelf, without Addition, 
 prefently runs into Glafs. And whether other 
 Ingredients mdght not here be advantageoufly 
 fubftituted for foft Sand, particularly calcined 
 Flints, powdered Cryftal, Qc, we recommend to 
 farther Experience ; fo as to attempt making a 
 Glafs that fhall, in fome Degree, approach the 
 Hardnefs of a Diamond. 
 
 40. If a pure tranfparent Glafs, of this De- 
 gree of Hardnefs, can be tinged in the ordinary 
 Manner, by Means of the prepared metalline 
 Calces, it Ihould feem that the Art of making 
 counterfeit Gems would then have gained its 
 Perfection ; for the Colours thus introduced are 
 in no refpeCt inferior, but perhaps fuperior, to 
 the natural Colours of the Sapphire, Emerald, 
 
 Ruby, So that nothing more feems want- 
 ing to perfect this Art, than the Difcovery of a 
 denfe, hard, cryilalline Glafs, that fhall polifli 
 like Cryftal, and not fcratch in the Wjear. 
 
 41. In order to give our Glafs the Expe^ 
 
 Degree of Hardnefs, it may be proper to conti- ex- 
 nue it long in the Fire ; which is conftantly 
 
 found to add Strength and Flardnefs to Glafs : 
 Infomuch that common Glafs, by being con- 
 ftantly kept in a ftrong Fufion for a Month or 
 fix Weeks, has become of a ftony Hardnefs ; a 
 large Part of the fixed Salt thus going off in 
 the Fire ; and confequently leaving the Glafs 
 lefs charged with Salt, or nearer approaching to 
 the native Hardnefs of the Flint or Sand em- 
 ployed in the Preparation. 
 
 G g 4 
 
 42. If 
 
45^ 
 
 Lecture the Twentieth. 
 
 42. If theUfe of Borax fhould, in this Man- 
 ner, be found to have a confiderable EfFed, it 
 will be proper to enquire farther into its natu- 
 ral and chemical Eliftory, which feems at pre- 
 fent CO be little regarded. Perhaps it may not 
 be iinpolTible to find this ufeful Subtf ance in fome 
 Parts of Europe^ or to imitate it by Art, and to 
 difcover better Ways of refining it than thofe 
 nov/ ufualiy pradifed. 
 
 43. The Facility wherewith this Salt runs into 
 Glafs, or the fmall Degree of Hear, and the fhort 
 Time required for that Purpofe, if well attended 
 to, m,ay be capable of enriching Chemiftry, and 
 more particularly the Hiflory of Glafs ; at lead 
 we have good Reafon to believe that the prefent 
 Experiment is capable of being largely diverfi- 
 fied, and improved to the Service of fevera! 
 Arts. 
 
 Experiment IV. 
 
 A Foil for turning fpherical or other figured Glajfes 
 into Speculums, 
 
 The Sil- Ounce of clean Lead, 
 
 and melted it with an equal Weight of pure 
 Amalgam, Tin *, then immediately added half an Ounce of 
 Bifmuth, and carefully fkimmed off the Drofs : 
 Now removing the Ladle from, the Fire, we ad- 
 ded, before the Mixture grew cold, five Ounces 
 of pure Qtiickfilver, and ftirred the whole well 
 together ; then put the fluid Amalgam into a 
 clean Glafs. 
 
 Uonxjtobe 45. When this Amalgam is ufed for Foiling, 
 applied. or Silvering, let it firft be (trained through a 
 linen Rag j then gently pour fome Ounces there- 
 of into the Glafs intended to be foiled. The 
 Mixture fliould be poured into the Glafs by 
 Means of a paper Funnel, reaching almofl; to 
 
 the 
 
457 
 
 Of Enlarging Chemljlry^ See. 
 
 the Bottom, to prevent its flying to the Sides ; 
 then dexteroufly inclining the Glafs every Way, 
 endeavour thus to fallen the Foil. When this 
 is once done, let the Glafs reft for fome Hours ; 
 then repeat the Operation, till at length the fluid 
 Mafs is evenly fpread and fixed over the whole 
 internal Surface •, as it may be known to be by 
 viewing the Glafs againft the Light. The fuper- 
 fluous Amalgam being now poured out, the 
 Outfideof the Glafs may be polifhed with Putty, 
 
 Chalk, or Tripoli, fprinkled upon a Cloth: 
 
 And thus the Operation is compleated. In 
 this Manner are made thofe fliining fpherical 
 Glafles (appearing like Glafles filled with Quick- 
 filver) which we fometimes fee hung up in Par- 
 lours, near the Cieling, to invite the Flies in 
 Summer from the Windows, and other Parts 
 of the Room, where they might prove more 
 offenfive. 
 
 46. The Operation has confiderable Advanta- Advanta- 
 ges, as being performable in the Cold; and is 
 
 not attended with Danger from the poifonous 
 Fumes of Arfenic, or other unwholefome Mat- 
 ters, ufually employed for this Purpofe. And 
 how far it is applicable to the more commodious 
 foiling of the common Looking-GlafTes, and 
 other Speculums, may deferve to be confidered. 
 
 Experiment V. 
 
 A curious and ufeful Glue. 
 
 47. We took an Ounce of Ifing-Glafs beat 
 
 «o fhreds, and put it into a Pint of Brandy *, Glafs 
 where, by Means of a little Pleat, or gentle fim- 
 mering over a common Fire, it gradually diftbl- 
 ved : We then ftrained the Solution through a 
 Piece of fine Muflin, and thus obtained a 
 
 Glue, 
 
458 
 
 Its Vfa. 
 
 Esitsnded. 
 
 And }m^ 
 pi oved. 
 
 Lecture the Twentieth. 
 
 Glue, that fhould be kept in a Glafs clofc 
 flopped. 
 
 48. This Glue, with a very gentle Heat, 
 difTolves thin, tranfparent, and alnioft limpid : 
 When ufed in the Manner of common Glue, it 
 joins the Parts of Wood together, ftronger than 
 Wood is joined to itfelf \ fo that the Pieces thus 
 joined will break in any other Part rather than 
 where they are glued. It is alfo remarkable, 
 that if Saw-duft, or powdered Wood, be made 
 into a Ball with this Glue, the Ball will prove 
 folid and elaftic j fo that it may be turned and 
 ufed as a Bowl, without breaking. And whe- 
 ther, by Means of fuch a Glue as this, fome- 
 thing confiderable may not be effedled in the 
 emboffing of Wood-work, we leave to farther 
 Experience. The Glue being thus made with 
 Brandy, will keep long v/ithout corrupting ; 
 and is therefore a proper Form wherein to pre- 
 ferve Ifing-Glafs ready dilTolvcd for the fining 
 of Wines, or other Ufes. 
 
 49. Another curious Ufe of our Glue is, that 
 it ferves excellently for taking off the Impreffions 
 of Medals, or Coin : Thus if a little of this 
 melted Glue be poured thinly upon a Guinea, 
 fuppofe, fo as to cover the w^hole Surface of the 
 Piece, and the Glue be fuffered to remain there- 
 on for a Day or tVv^o, till it becomes thoroughly 
 dry, It will appear hard and tranfparent, like 
 a Piece of Muj'covy-Q\'2i{^^ with the Impreffion of 
 a fair Guinea in Entaglio^ as they call it, on one 
 Side, and in Relievo on the other. 
 
 50. This Glue, therefore, dries into a very 
 ftrong, tough, and tranfparent Subftance *, not 
 eafiiy to be hurt or damaged by any Thing but 
 aqueous Moiflure, which would foon diffolve it: 
 So that it is not fit to be ufed in any Work that 
 muft be expofed to Wet or Weather. But for a 
 
 Glue 
 
459 
 
 Of Enlarging Chemifry^ See. 
 
 Glue to ftand the Weather, let choice be made 
 of the common Glue diflblved with Linfeed- 
 Oil. 
 
 51. The natural and experimental Hiftory of HiHory of 
 Glue might greatly tend to the Improvement of^-^ 
 Chemiftry. For it fliould feem as if ail animal 
 
 and vegetable Subftances were either originally 
 made of, or might at laft be refolved into 
 Glue or Jelly. Doubtlefs a Knowledge of the 
 Nature of Ropinefs, Vifeidity, Sizinefs, Moul- 
 diaefs, would give confiderable Light to 
 Natural Fhilofophy and Medicine, and lead 
 us farther into the Effeds, Nature, and Procefs 
 of Growth, Fermentation, and Putrefadlion. 
 
 This Enquiry, therefore, fhould be profecuted 
 with Care ; beginning, for Example, with that 
 vifeous Subftance the White of the Egg, or Se- 
 rum of the Blood, in their natural States •, and 
 obferving how their Tenacity is altered, by mo- 
 derate Degrees of Warmth or Cold. The En- 
 quiry might next proceed to the mucilaginous 
 Matter of Snails, Frog-Spawn, Fifli, and other 
 Animals in Embrio, Vegetables, Cfc. and gra- 
 dually defeend to Subjedts of the mineral King- 
 dom. And this Enquiry, v/e apprehend, may 
 be ufefully profecuted without the Affiftance of 
 a chemical Apparatus •, fo as to difeover the 
 bed Ways of preparing Cements, Glues, Sizes, 
 
 Jellies, Cfc. for various mechanical and oeco- 
 nornical Ufes. 1 
 
 Ex PERIMENT, VI. 
 
 Copper made more duEllle^ and turned of a Gold 
 Colour. 
 
 52. Make an Amalgam, of one Part pure 
 Copper, and three Parts clean Quickfilver ; 
 
 boil 
 
460 
 
 Copper ad^ 
 wanced 
 fome’vjhat 
 nea >^er to 
 Gold, 
 
 Its U/e. 
 
 Lecture the Twentieth. 
 
 boil the Amalgam in River-Water for two 
 Hours ; then diftill off the Quickfilver,and coho- 
 bate It once or twice laftly, fufe the Copper 
 that remains in the Retort, and it will be of a 
 Gold Colour, and more dudbile than common 
 Copper. This Experiment was not brought to 
 Pertedlion in the Courfe, on Account of the 
 Difficulty then found of amalgamating the Cop- 
 per, which was attempted thus : We diffolved 
 as much Copper in Aq^ua forth as the Menflruum. 
 would take up ; then diluting the Solution with 
 ten or twelve Times its own Weight of Water, 
 we put Iron Plates into it, which precipitated 
 the Copper in fine Powder : This Powder was 
 edulcorated, or walked, in feveral Waters, to 
 clear it of its adhering Salts, and afterwards 
 dried ; then ground in a Stone- Mortar, along 
 with an equal Weight of Quickfilver j but no 
 Amalgamation enfued. It has been ufually 
 thought difficult, and by fome impradticable, 
 to make an Amalgam of Copper by Heat : In 
 which Method, indeed, it is not eafy to fucceed 
 perfedlly, the Copper requiring fuch a Heat to 
 keep it fluid, as will exhale the Mercury ; which 
 befides docs not readily unite with that Metal. 
 In the prefent Method the Thing may be effeded 
 without Heat ; viz. by firfl reducing the Copper 
 to an exceeding fine Powder; which here fup- 
 plies the Place of Fufion,and might put us upon 
 enquiring whether Trituration may not, in fome 
 other Cafes, be advantageoufly fubflituted for 
 Fufion. 
 
 53. This uncommon Experiment of M. Horn- 
 berg fhevvs us a Method of advancing Copper 
 fome Degrees nearer to Gold ; fo as to fit it 
 for Watch- work. Cane-heads, Snuff-boxes, and 
 other fmaller Machines and Utenfils, and efpe- 
 cially for Gilding. It is remarkable that the 
 
t 
 
 461 
 
 Of Enlarging Chemijlry, 8cc. 
 
 Quickfilver lofes an eight Part of its Weight in 
 the Operation. 
 
 54. The Experiment is here employed as a Extended, 
 leading one, capable of fhewing that ufeful 
 Changes may be wrought upon the common Me- 
 tals ; fo as, in fome Meafure, to introduce a new 
 
 Set. It is known to fome, that Copper may be 
 fo far whitened and foftened, as to ferve on ma- 
 ny Occafions for Silver. Lead, by a flight Ap- 
 plication, is capable of being whitened, harden- 
 ed, and rendered more ufeful for many Purpofes. 
 
 And if Perfons acquainted with the Nature and 
 Effedls of Metals, Minerals, and their Fumes 
 upon each other, were to profecute the Enquiry, 
 many ufeful Things of the like Kind might 
 doubtlefs be difeovered. 
 
 55. A little prepared or fixed Arfenic will in- Exemplh 
 ftantly whiten Copper throughout ; though thusA^* 
 indeed the Copper proves brittle, or rotten : 
 
 But there are other fecret Ways of whitening it, 
 fo as to leave it extreamly dudiilc. 
 
 56. The farther Profecution of this Subjefb TheProfe- 
 would lead us into the fublimer Metallurgy ; 
 which is a Part of Chemiflry by no Means hi- 
 therto cultivated as it deferves, feeing it is highly 
 capable of enriching the known mechanical Arts, 
 
 and ftriking out new ones. 
 
 • III. 
 
 57. We now come to offer a few ^uks for Rules for 
 condufling chemical Experiments in the Way of impron:ing 
 an Art ; fo as to improve the feveral Branches 
 
 of Chemiflry above mentioned *. 
 
 58. Let the firfl; Rule be, with Care and Dili- 
 gence to obferve the Proceffes ufed by Nature in . 
 
 * § 2, ' 
 
 the 
 
462 Lecture THE Twentieth, 
 
 the Produflion of all thofe things we would en- 
 deavour to imitate. For Nature, the moil ex- 
 pert Chemift, employs the very Inflruments which 
 Men a) lb employ ; viz Fire, Water, Air, and 
 Earth *, as we have fhewn in our Lectures upon 
 the Elements. 
 
 lilujlra- 59 ‘ To illuftrate this Rule by an Example •, 
 
 tion, it appears, by numerous Inftances, that there is 
 an acid or faline Liquor naturally contained in 
 the Bowels of the Earth *, which acid there mix- 
 ing with various Kinds of earthy Matters, and adt- 
 ing as a Menftruum upon them, changes their 
 Natures, or makes them appear under different 
 Forms. And hence common Brimftone, Alum, 
 the native Vitriol, fecm to have their Origin. 
 
 60. For by an exadl Scrutiny and attentive 
 Confideration it appears that, when this general 
 Acid diffolves a certain bituminous Earth, it 
 makes Brimftone ; when a chalky Earth, Alum ^ 
 when Iron or Copper, Vitriol ; And accor- 
 
 dingly, by ufing the fame Kind of general Acid 
 (which may be procured by burning Brimftone 
 under a glafs Bell) in the fame Manner as Na- 
 ture feems to employ it, we can likewife, by 
 Art, produce Brimftone, Alum, or Vitriol, when 
 and where we pleafe. And thus, if we could 
 univerfally difcover the Proceftes and Inftru- 
 ments which Nature employs in thg Produdlion 
 of her Effedls, we fliouid have certain Rules for 
 imitating her. 
 
 Kulell Our fecond Rule is, to gain a Habit of 
 
 transferring, diverfifying, enlarging, and improv- 
 ing an Experiment, till it ends in fome certain 
 Difcovery, either of Light to the Underftanding, 
 or of Ufe in Life •, one of which points all juft 
 Experiments will end in, when duly profecuted 
 and confidered. 
 
 62. For 
 
Of Enlarging Chemifry^ See. 4 . 6 - 
 
 62. For unfuccefsful Experiments are no lefs IZ/uj^ra^ 
 inftru( 5 ling than thofe that lucceed : Which 
 ought to be well remarked. The Head mud in 
 
 all Cafes co-operate with the Hands : So that 
 the Mind fliould be ever calling about to difeo- 
 ver the Caufes of Failure, as well as of Succefs. 
 
 And this is a Sagacity which may be procured 
 by Ufe, and turned into a Habit of Invention 
 and Difeovery : So that no fingle Experiment 
 fhali be performed, but fome Advantage will 
 be immediately derived from it *, nor any Experi- 
 ment be made, without fome reafonable Grounds 
 of Hope for Succefs. 
 
 63. Our third Rule is. To profecute Experi- Mill 
 ments in an orderly Series, with a View to fome 
 particular Enquiry that may be of Ufe in Life ; 
 
 and to let the Enquiry fuit the Genius and Tem- 
 per of the Enquirer, fo as that it may be profe- 
 cuted by h m with Vigour and Pleafure. 
 
 64. Thus, if any one fliould be averfe to the lllujlra- 
 Ufe of Fire and Furnace, he may dill improve tion. 
 Chemidry and Arts, or perform many fervice- 
 
 able chemical Operations, without much Appa- 
 ratus, or Expence, or without the Utenfils and 
 Indruments commonly employed in that Art : 
 
 Which may, therefore, be pradifed as well in 
 a Study or Parlour, as in a Laboratory. And 
 to thofe difpofed to operate in this Way, may 
 be recommended the Bufinefs of P'ermentation, 
 the Concentration of Liquors by Cold, and the 
 Profecution of the Nature and Hidory of Cold, 
 begun by Mr. Boyle. We might alfo recommend 
 the extracting of the finer ElTences of Vegeta- 
 bles i the making of the more noble and fpiritu- 
 ous Infufions, Tinctures, and Elixirs *, the exa- 
 mining and tabling the folutive Power of Water 
 with regard to Saits, and of Spirit of Wine with 
 
 regard 
 
464 Lecture the Twentieth. 
 
 regard to different Oils and Rofins ; the deter- 
 mining the Force of all known Menftruums in 
 the Cold ; the Difcovery of new Menftruums, 
 and particularly of a Solvent for the Stone. Thefe, 
 and many other chemical Enquiries, may be 
 profecuted without the Ufe of Fires and Fur- 
 naces : And even fuch Tempers as are more de- 
 lighted with Speculation than Pradlice, may 
 greatly contribute to the Improvement of Che- 
 miftry, by forting, ranging, and digefting Ex- 
 periments into Tables ; fhewing what they prove, 
 and how far they reach ; how far they fall fhort, 
 and how they may be carried farther : Others 
 might employ themfelves to Advantage, in 
 drawing Things of Ufe from the Experim.cnts 
 already known and publifhed : And laftly, 
 others might, from a due Confideration of 
 Experiments, deduce new Dire6fions and Rules 
 of Practice for producing, in a fure and con- 
 ftant Manner, much greater Effeds than are 
 ufualiy hoped for. 
 
 Axioms and Canon s. 
 
 I- We learn from the prefent Le6fure, that 
 Chemiftry is an Art of very extenfive Ufe in 
 Life ; infomuch that not only Natural Philofo- 
 phy, but alfo Trades, Commerce, and all adlive 
 Bufinefles, have a Dependence upon it, and may 
 be improved by it 
 
 2 . That therefore the Difefteem, which Che- 
 miftry has generally met with, proceeds from a 
 Want of knowing its proper Office, Extent, and 
 Ufefulnefs^ and from the frequent Mifapplica- 
 
 ^ See the whole Lecture paJJJm* 
 
 tion 
 
Of Enlarging Chemifiry^ &c. 
 
 tion of it to Things of a delufory or phantafti- 
 cal Nature. 
 
 3. That a large Part of general Chemiftry 
 may be advantageoufly pradlifed, and many Di- 
 fcoveries and Improvements made therein, for 
 the Service of Arts, without the dired Ufe of 
 Chemical Fires, Furnaces, and the common Af- 
 f aval us a), 
 
 4.. That numerous Difcoveries and Improve- 
 ments remain to be made in Chemiftry itfelf \ 
 and that thefe Improvements m.ay be made in 
 a dired, rational Manner ; and, if once made, 
 might greatly enlarge and illuftrate Natural Phi- 
 iofophy, improve various Arts, and introduce a 
 Set of new ones h). 
 
 5. That, in particular, Sal-Ammoniac, an Am* 
 her-Varnifh, a .hard Kind of Glafs, a Foil for 
 Glaffes, an excellent Glue, and a new Kind of 
 Metal, may be eafily obtained, for the Improve- 
 ment of Pharmacy and Dying, Japanning and 
 Embalming, the Art of Glafs and the making 
 of artificial Gems, the Foiling of Glaffes, the 
 Gluing of Timber, Emboffing, and taking off 
 Impreffions, the Art of Watch-making, and for 
 other mechanical Ufes. 
 
 6. That the Canons for the farther Improve- 
 ment of Chemiftry, and the Arts thereon de- 
 pending, require, (i) a careful Obfervation of 
 the Ways of working employed by Nature; 
 (2) a Talent of Experimenting *, and (3) the 
 Diferetion of fuiting the Enquiry to the Temper 
 and Genius of the Enquirer c), 
 
 a) See § 12, 13. and Exp. II. IV^. V, and § 63, 64% 
 
 h) See the whole Lefture. 
 
 c) See § 
 
466 Lecture the Twentieth. 
 CONCLUSION. 
 
 E are now come to the End of our Lec- 
 tures, where it may be proper to ftop 
 a while, and look back upon the Ground we 
 have gone over. We feem to ourfelves to have 
 been travelling in a new Road, too little fre- 
 quented cither by Philofophers, Chemifts, or 
 Men of Bufinefs. Our Aim has been to im- 
 prove the ufeful Arts, by Means of a more Phi- 
 lofophical Chemiftry j and at the fame Time to 
 ihew the Method of condudling Enquiries fo 
 as that they may terminate in ufeful Difeoveries. 
 With an Eye fixed upon this Point, we have 
 purpofely avoided the more entertaining and 
 agreeable Experiments, wherewith Chemiftry 
 abounds ; and have kept to fuch only as were 
 judged either beneficial in themfelves, or of Ser- 
 vice in difeovering Caufes, Axioms, and Rules. 
 And if there be any Merit in what we have done, 
 we freely own it to be borrowed, and that it lies 
 in the Venilamian Method we have purfued, that 
 is, in endeavouring to rectify the Mind, guard 
 it againft Error and lllufion, and condu6l it to 
 the Fountains of Nature and Ufe. We cannot 
 indeed prefumc to have difeovered many of the 
 true Caufes of Things, or Axioms perfectly juft 
 and univerfal. To do this, requires that the fe- 
 veral Parts of Philofophy fhould be better cul- 
 tivated than they are. All we can hope for is, 
 to have found and eftablifhed a few Rules 
 that may dircFc to a ferviceable Pradlice, and 
 enable us to enrich and improve fome of the 
 prefent A^rts and Sciences. Thus, for Example, 
 we hope to have difeovered this philofophical 
 Axiom, That Sugar ^ or a faccharine Suhftance^ is 
 the Bafts of JVines^ Beers, Vinegars, and infiam- 
 
 mahle 
 
Of Enlarging Chemiftry^ &c. 
 
 mahle Spirits : Whence we prefume, that the Arts 
 of Brewing, Wine-making, Vinegar- making, 
 and Diftilling, may receive a great Degree of 
 Berfeclion. And thus we defire to have it ob- 
 ferved, that the Difeovery of a fingle Axiom, 
 or Caufe, may often improve, or even perfedt, 
 a Number of Arts : For phyfical Axioms, duly 
 difeovered, mud be pregnant with the Matter 
 of many Arts and Sciences. And on this Ac- 
 count it is, that we have dire(5led our Enquiries 
 to the Inveftigation thereof, as the bed and fured 
 Means ot improving the known Arts, and dif- 
 covering new ones. Doubtlefs, if this Method 
 were carefully and generally purfued, the Bud- 
 nefs of Invention would not long continue to be 
 that caiual Thing it nowds; but be reduced to 
 an Art, which, of all others, is, perhaps, the 
 mod wanted. 
 
 ne END. 
 
 H h 2 
 
 INDEX. 
 
I N 
 
 EX 
 
 A. 
 
 
 ^Ggregates 
 
 -what 
 
 i6 
 
 Agents^i natural^ what 
 
 1 1 
 
 Agnciilture^ how improve- 
 able 1 ^’> 
 
 Air^ its injlrumental Effi- 
 cacy 12 — f7 
 
 necejfary to Fire 31-57 
 
 fpoiled by Fire 1 2 
 
 its PreJJure 44? 45 
 
 its Elafticity ib. 
 
 ' — its compound Nature 46, 
 
 55 
 
 — contains Water 47 
 — » required frejh in Refpi- 
 ration 48, 49 
 
 - — may and may not pro^ 
 mote Solution 50, 5 1 , 5 7 
 ^ — contained in Fluids and 
 Solids 49, 50 — 53 
 
 • — its Abfion on Liquors 55 
 ' — why fluid ^7 
 
 how analyfed lo, ii 
 
 Alab after calcined 69 
 
 Alchemifts^ their Frauds hovo 
 difc over able 107, 109 
 
 Alcohol^ what^ and how made 
 165 100, 132 
 its diffiolving Power 
 
 100, 112 
 
 its Ufes 133 
 
 Alterants 357 - 
 
 Amalgamation explained 105, 
 106, 395,45^ 
 Amber ^ how dijflolved 452, 
 
 453 
 
 Amber-Varnifb 452 
 
 Animals^ their Chemical Prin- 
 ciples 154 
 
 Anodynes 361,362 
 
 AquaFortis jo8 
 
 Aqua Regia ib. 
 
 Arts^ how improveable 58 
 AJflaying^ what 392 
 
 — — how improveable 
 
 397 
 
 Atmofphere^ what 42 
 
 how divided 10 
 
 “ — ^ — its Ufe in Chemiftry 
 
 42 
 
 — — how examined ib. 
 receives Vapours 
 
 > 44 
 Atmo- 
 
^Atmofpbere^ its phyfical Agency 
 53^ 58 
 
 its component Farts 
 
 55. 5 ^ 
 
 may aEl as a Men' 
 
 fbruum 58 
 
 its phyftcal Ufes 7 1 , 
 
 72. See Air. 
 Aurum fulminans 109, 294 
 
 B. 
 
 DArk^ Peruvian, its Ex- 
 traa 358, 359 
 
 Black ‘Flux 7, 8 
 
 Blafting in Mining 375 
 Bodies^ hew divided in Che- 
 miftry 5, 6 
 
 — how refolved chemically 
 15, 16 
 
 — ■ — fenjible^ compofed of in- 
 fenfible 16, 23 
 
 — — their Relations and 
 
 INDEX. 
 
 Brewing 202, 207, 215, 
 
 217 
 
 Burrows^ in Mining 374 
 
 C. 
 
 f^Alamy, its Nature 409 
 ^ Calces of Metals^ how re- 
 dticed 402, 403 
 
 Calcination^ its Effcdls 74 
 Callico- Printing improv cable 
 
 313^ 
 
 Camphircy diffolved m Alcohol 
 
 TOO 
 
 its Virtues ‘and Ufes 
 
 355. 356 
 
 Carmine^ how made 307 
 Cafe- hardening 4 ^ 2 
 
 Cathartics 352—354 
 
 Cement for Water-Pipes 103 
 Cerates^ how made 340 
 Chemiftry^analytical^ what 145 
 how improve able i , 
 
 Changes 
 
 18 
 
 23, 24, 41, 97> 115, 
 
 their Properties how 
 
 1 16, 160, 161, 441, 443 
 
 learnt 
 
 22 
 
 — Advantages of im- 
 
 Bofie foftened 
 
 110, III 
 
 proving it 1 9 
 
 analyjed 
 
 154 
 
 philofophical^ what i , 
 
 recompofed 
 
 176, 177 
 
 441, 44* 
 
 Borax^ its Glafs 
 
 454. 455 
 
 its Inftruments ii. 
 
 Bonng in Mining 
 
 27 ° 
 
 14 
 
 Brandy analyfed 
 
 16, 172 
 
 its Objedfs 2 — 5, 23 
 
 
 173 
 
 its Jjivifton 1 5, 440, 
 
 — — > how tried 
 
 125, 126 
 
 441 
 
 
 I3I, 132 
 
 its EffePds j8 
 
 what 
 
 130 
 
 — . l)GW to he conducted 
 
 Brafs^ how made 
 
 409 
 
 20, 21 
 
 Bread analyfed 
 
 104 
 
 its PerfeWton what 
 
 its Spirit 
 
 104, 105 
 
 22 
 
INDEX. 
 
 Chem^ftry of Nature 138 
 pharmaceutical^ what 
 
 321 
 
 technical^ divided 444 
 
 how improve- 
 
 able 445,446 
 
 — 0 economical^ how im- 
 
 proveable 446, 449 
 
 — fyntheticaf what 
 
 168, 169 
 
 Cinnabar re comp 0 fed 174, 175 
 Citron Water^ how made 255 
 Coals^ their Inflammability 
 whence 30 
 
 Cold^ its natural Effedis j 
 Colours what 294, 296, 318 
 
 how generated and 
 
 296, 305 
 how concentrated for 
 Dyings &c. ^ 307, 308 
 
 how improveable for 
 
 Paintings &c. 313, 316, 
 
 318, 319 
 
 Compofls^ what^ and how made 
 
 72, 73 
 
 Conflagrations^ how prevented 
 
 .... 
 
 Conflituent^ its Signification 1 5 
 Cordial V/aters^ how made 
 
 255 
 
 Ccrufcations made by Art 42 5 
 Copper refemhling Gold 459, 
 
 460 
 
 Cur alien ^ what 184, 185, 
 196 — 198 
 
 D. 
 
 j^Amps^ whence 
 
 69 
 
 Digeflory what no 
 
 its life 1 10, III 
 
 — how improveable in, 
 
 Eifiillation^ what 242 
 
 of JVaJh 257, 258, 
 
 244, 246 
 
 compoundy improved 
 
 255, 256, 264 
 
 Fine- Stilling improved 
 
 258 
 
 E. 
 
 JIf Arthy its general StruBure 
 
 ~ — in particular y what ib. 
 ■ — ana! y fed 7, 60 
 
 its phyftcal Ufes 72, 73 
 
 Earthquakes explained 296 
 
 Earths y what 73 
 
 their Species 59, 60, 
 
 65— ^7> 7* 
 
 Efl'cBSy chemicaly their Caujes 
 
 *9 
 
 great ones how produ- 
 
 cible 
 
 22, 2 
 
 Eledtuaries how bed made 
 
 Embalming 
 
 335 ' 
 
 349 = 
 
 339 
 
 453 
 
 35 ^ 
 
 26/ 
 
 Emetics 
 
 Emulfions bow made 
 Enamelling 
 
 El^jofaccharums 279 
 
 292, 360, 361 
 
 o 
 
 3'7 
 
 2b’0.. 
 
I N D 
 
 EJfay-Liquor for Brandies 
 2539 254 
 
 EJfences ’266, 26y 
 
 Experiments^ their Ufe 22 
 
 F. 
 
 ~r?Ermentation^ what 140, 
 
 141 
 
 its Bohlrine 117 — 130 
 
 its Efficacy 129,130 
 
 vinous 1 3 1, j 93 -—201 
 
 Obfervations there- 
 
 on 
 
 201 
 
 acetous 
 
 how determined 
 
 213 
 
 ^33 
 
 — its Subjehls 141 
 
 — its Species 138, 141 
 
 - — how flopped and pre- 
 vented 142, 144 
 
 its Degrees 
 
 14 
 
 whether in animal Bo- 
 dies 143, 144' 
 
 — whether in dry Bodies 
 138, 144 
 where performed 1 44 
 
 E X. 
 
 Fire^ its Kinds and Effects 
 28,^4,39 
 — — its Degrees of Purity 
 
 35 ^ 3 ^ 
 
 — — m^xes and analyfes 23 
 — — its Form and Matter 
 
 Its Ufes 39, 40 
 
 * how prevented and ex- 
 
 tinguijhed ib. 
 
 requires Air 57 
 
 produced by Iron and 
 
 Sulphur 423 
 
 — by two cold Liquors 
 
 427, 4293 43S 
 
 33 
 39 
 
 34 
 
 49^50 
 
 258, 
 
 3^3.38^ 
 
 386 
 45 ^ 
 
 Ferments-, their Doblrine 122, 
 
 124— I3N 142, 143 
 
 — their Ufe 142, 143 
 
 Fertility, whence 7^5 72 
 Fewel-i what 2 9 
 
 * Oil effiential to it 2<^, 30 
 
 how charred 33 
 
 Fire^ what 25, 26, 40 
 bow to be judged of 26, 
 
 27. 38 
 
 Flame, fuperficial 
 
 what 
 
 its Colours 
 
 Fluids contain Air 
 Fluxes^ their Kinds 
 
 improved 
 
 Foil, for Qlaffies 
 Forefl-Frees, how improve- 
 able 72 
 
 Fujion^ metallic^ how improve- 
 abk 403, 404, 406 
 G. 
 
 fjElfy, what 177, 178, 
 181, 182 
 
 Glafs., how flained red 313 
 
 a hard one 454, 455 
 
 Glue^ a curious one 357, 358 
 Glues., their Hiflory 459 
 
 Gold diffiolved 107, 108 
 
 Ufes of its Solution 109 
 
 - — how feparated from SiU 
 ver 397, 398 
 
 Cold, 
 
INDEX 
 
 Gold^ how ohtainable pure 
 
 399 
 
 - - imitated 
 
 410 
 
 Graves in Chandlery.^ thrir 
 .Ufe 
 
 Gunpowder how made 417 
 ~ - its Rationale 418 
 
 “ its Difeovery 419 
 
 - - how tried 419,420 
 » “ how Jlrcngthened 420 
 Gypfum, what .and huw made 
 
 70 
 
 II. 
 
 ZJyf/r, how changed black 
 ro8, 109 
 
 Heat^ its Ejfebls 1 2 
 
 « - its Charadierijiics 26 
 « - its Kinds and Degrees 
 
 Lime^ how improve able 74 
 Loamy how made Clay 64, 
 
 65 
 
 M. 
 
 265 l^Alting 186, 187, 189 
 Mar cafiteSy what 67 
 
 - - - - taking Fire 68 
 “ - - analyjed 68, 69 
 
 - - - - how turned to Ufe 
 
 74 
 
 - - - - their phyfical Ufes 
 
 ib. 
 
 Matching of Cafs 191, 
 Matrices y their Inftrumenta- 
 
 30--38 - 
 
 lity 
 
 Medicines clafj'ed 
 Menilruums, what 
 ■ - folid and fluid 
 
 13 
 
 348 
 
 95 
 
 ib. 
 
 ♦ - how regulated 
 
 36. 37 
 
 ^ ^ ^ . of Nature 96 
 
 ~ - its Form 
 
 38 . 40 
 
 their Ufe 10 r, 102 
 
 Hot Bathsy whence 
 
 60 
 
 - - - - hovo improveable 1 1 2 
 
 Hygrometers for I^aboratories 
 
 - - - - their Power how 
 
 
 93 ^ 94 
 
 found 1 1 3 , 1 1 4 
 
 I. 
 
 
 - - - - their Allion whence 
 
 INflarfimahility^ whence 30 
 InfufionSy hoiv heft made 
 
 328 --3 32, 344, 345 ones recommended 
 
 ib. 
 
 the 'Difeovery of nevo 
 102, 
 
 I 
 
 Integrality what 
 Ipecacuanha an aly fed 350 
 Juices, cf Vegetables^ how 
 
 cured 
 
 L. 
 
 ^S3- 
 
 95 
 
 T AqueSy how made 306, 
 
 . 307 
 
 Light y its Compofition 294, 
 
 ^■9 A 3 ^^ 
 
 105, 116 
 Mercurifleation 160 
 
 Mercury y a Principle 160, 
 
 161 
 
 Metallifty^ his Qualifications 
 
 368 
 
 Metallurgy y what 367 
 
 - ~ hovo improve able 387, 
 
 • 412. 415 
 
 Meialsy 
 
I N D 
 
 Metals^ whether to he ri- 
 pened 94 
 
 —— how dijlinguijhahle 
 
 103, 109 
 
 how dijfolv able 112, 
 
 obtainable without 
 
 Mining 373 
 
 how feparated from 
 
 each other 407 
 
 Meteors^ their Origin 54, 
 
 424 
 
 Minerals^ their chemical 
 Principles 159 - 162 
 Mineral- Waters^ how ex a- 
 
 ,56 
 
 mined 
 
 . — • how imitated 
 — • their Analyfis 
 Mineralogy^ what 
 its Reqiiiftes 
 
 MineSy how fired 
 — ^ how difccvered 
 
 87-89 
 89-91 
 
 94 
 
 368 
 69 
 
 369. 
 370 
 
 their Signs 370 
 
 — - how heft dug 371, 372 
 Minings its Profit 
 
 its Requifites 
 
 369 
 372 
 
 Mixts^ what 1 6 
 
 Mixture^ its Produuiions 1 8 
 Mould analyfed 60-64 
 
 Mundic analyfed 68, 252. 
 
 See Marcafitcs. 
 
 N. 
 
 how refined 283, 
 292 
 
 E X. 
 
 Nitre^ its Hiftory 
 
 its Virtues and Ufes 
 
 1 , 51 ^ 358 
 
 regenerated 169, 
 
 170 
 
 O. 
 
 the inflammable Prin- 
 dple 39 
 
 its dijfqhing Power 
 
 102, 103 
 
 its Relation to Metals 
 
 103, 104 
 
 — of Almonds y how made 
 
 262 
 
 Juniper^ how made 
 
 267, 268 
 
 may lie concealed 289, 
 
 290 
 
 how rendered mifcible 
 
 with Water 290, 292 
 
 Oils by Exprefiion 2 6 1 - 2 6 3 
 
 how to be kept 
 
 264, 290 
 
 coloured 265, 266, 290 
 
 ejfential^ how made 
 
 267-270, 290 
 claffed 268 
 
 — how tried^ and 
 
 adulterated 271-274 
 
 — empyreumatic^ how 
 
 reblified 274, 275, 291 
 Oleum animale, 275 
 Opacity^ what 318 
 
 Operations^ chemical^ require 
 different Heats 41 
 
 — how they may 
 
 vary 56 
 
 Opium prepared 361 
 
 Ores^ 
 
INDEX. 
 
 Ores y how analy fed 8,9,316 Principles^ what 145-147, 
 
 ■ how roafted 376-380 162-167 
 
 ■ howfiampedandwajhed Proofs in Spirits^ what 252, 
 
 380-382 253, 259,260, 346, 
 
 of Gold and Silvery 347, 35 ^^ 35 ^ 
 
 fefed 39^9 394 Pruflian how made 
 
 • of Lead y off ay ed and . 30^9309 
 
 fmelted 401 Pelvis prepared 
 
 of G ,per tefted 408 421 
 
 Putrefa 5 Uon, what 128- 38 
 P. in Vegetables 134, 
 
 7 ;ArtSyConftituentandin- ^ ^35 
 
 tegrant 15 — — in Animals 136 
 
 Per fumes y how improved how checked or pre- 
 
 451 vented 142 
 
 Pharmacy, its Hiftory 321- Pyrites, 67 
 
 324, 346, 347 
 — — its End and Rules 
 
 324 
 
 , — — how improveahle 
 
 345, 362-366 
 Phenomena of Nature y how 
 caufed 5 4 
 
 Phofpborus of Urine y itsHi- 
 Jtory 429-434, 
 
 435*437 
 
 — black 434 
 
 PlaiJlerSy hew made 340- 
 
 343 
 
 Pot'Afoy how made 285, 
 
 292 
 
 — . — its Kinds and Ufes 
 
 take Fire 140, See 
 Marcafites and Mundic. 
 Pyrotechny improveahle 310, 
 
 311 
 
 QUartationy what 397 
 
 ^icklime analyfed 66 
 ^ickjilvery whether metal- 
 lic 161. See Mercury. 
 — ^ — rendered invifibky 
 and recovered ^ 59 1 7 
 — — — its diffolving Power 
 105, U4 
 
 how adulterated 
 
 106 
 
 R. 
 
 285-287 J^compofttion illuftrated 
 Potteryy how improveahle 65 ^7 
 
 Precipitaiiony what 16,101 “* — how to be attempted 
 
 its Law I or 1719 17^ 
 
 princeS'lVletaly how made 'perfedl and imperfedi 
 
 409 179-181 
 
I N t> 
 
 Re^tjicatim of Spirits 131, 
 
 221 
 
 Refine, wba} , 126 
 
 Rivers^ why fertilizing 81 
 Ruby of Golf how made 
 
 184., 185 
 S. 
 
 C At- Ammoniac^ how made 
 342, 343 
 
 Silver dijfolved 107, 108 
 
 - - Ufes of its Solution 
 
 108 
 
 - - how recovered from its 
 
 Solution 1 09 
 
 “ - how feparated from Cop 
 per 408 
 
 - - how obtained pure 400 
 Simple floater ^ how beft made 
 
 ; 325 - 3=^-^5 343^ 344 
 Smeltings its Hiflory 1 60, 1 6 1 
 Soap - making improved 287, 
 288, 293, 
 Solders^ their Boblrine 103 
 Solution^ its Caufe 1 1 5 
 
 Spirits^ inflammable^ what 
 257, 258 
 
 - - how purified 258 
 
 - - native of Vegetables 290, 
 
 291 
 
 Steef how' made 411,412 
 Steepings for Grain 72, 73 
 Strengthens s 3 5 8 — 46 1 
 
 Stum^ what ' 191 
 
 Sudorific s 355 ? 35^ 
 
 Sugar ^ affords Wine 120,121 
 “ - how made and refined 
 270--278, 291, 292 
 
 “ - its Ufes 279, 280 
 
 E X. 
 
 Sulphury of MetalSy ''^swhat 
 103, \o4 
 
 - “ how feparated from Cop- 
 
 per^ 405 
 
 S'un^ its Effedfs 12 
 
 - - Purity of its Heat 28 
 
 Sweet Sy what 203 
 
 Syrups how beft made 332 
 
 — 335 
 
 T. 
 
 ^Artary how refined 280 
 -283 
 
 - - tartarized an extraordi- 
 nary Menflruum 282, 
 
 283, 292 
 
 "Tefting explained 3935394 
 Eexturey how changed 296 
 
 — 3G0 
 
 thermometers explained 46, 
 
 : 47 
 
 tindlureSy how be(i made 
 
 328-332. 344 
 
 318 
 
 75 
 
 T ranfparency. what 
 trituration, its Ufes 
 
 V. 
 
 JAApidity, what 128, 129 
 ^ Varnifloes 452, 453 
 Vegetables^ how preferved 72, 
 
 190 
 
 - - their Principles 148 
 
 - 151 
 
 Vegetation how proynoted 7 1 , 
 
 72 
 
 — how flopped 186 
 
 190 
 
 Veins of a Mine 37 3 74 - 
 Vinegar y how made 124-128 
 Vine- 
 
INDEX. 
 
 Vinegar^ its Subje 5 fs 117, 
 
 125 
 
 - - - its Procefs confidered 
 
 1 17, 125 126 
 
 - - - how putrefied 128 
 
 - - ' yields no Alcohol by 
 frm le ' iji illation 133 
 
 Vitriol fer Went ed 140, 1 9 1 
 
 U. 
 
 X -Ngients^ how hef made 
 
 340- 343 
 
 w. 
 
 f J/'Ater divided and ana- 
 lyfed 9. 10 75 
 ’ ” - its In'^mmentaHty 13 
 “ - - cOfUdnea in Air 47, 
 
 48, 77 ’ 7 ^ 
 
 ^ - an Analyfer 73 
 
 - - - in dry Bodies 75-773 
 
 91 
 
 - - - xontains Earth 79 
 
 - - - its Properties^ Office^ 
 
 andUfe 80 
 
 - « - whence fertilizing 80, 
 
 81 
 
 - - - its diffolving Power 
 
 81-83, 97, III 
 Jv - - its component Parts 
 83-85, 91, 92 
 
 - - - how to be examined 
 
 85-87 
 
 - - - its phyfical and che- 
 mical Ufes 91—94 
 
 - - - its different Forms and 
 
 Appearances 92 
 
 - - - how improved 94 
 
 - - - Sea-Water how made 
 
 fre(h ib. 
 
 F I N 
 
 Waters^ compound^ how bijl 
 
 made 255 
 
 Whitenefs^ what 1 90 
 
 White- Powder 420, 421 
 Wind-Guns 421 
 
 Wine^ how made from Rai- 
 fms 1 1 8 
 
 - - made from Sugar 1 2 1 
 
 - - how fined 207—209 
 
 - - its Difeafes how cured 
 
 209—220 
 
 - - white turned into red 
 
 210 
 
 “ - pricked^ recovered 214 
 Wines^ in general^ how made 
 118--124 
 
 - - the BoPtrine relating to 
 
 them ib. 
 
 - - how imi table ib. 
 
 - - how coloured 121 
 
 - - their Kinds 118, 119, 
 
 121 
 
 - - their Bafts 120, 121, 
 
 142 
 
 - - the made Sorts recom- 
 mended 119,120 
 
 - - how fpoiled or putrefied 
 
 128 
 
 - - - how preferved found 
 
 126,^128, 133 
 V/ornwoood analyfed 148— 
 
 *51 
 
 Y. 
 
 ajl how preferved j 9 5 
 
 Z. 
 
 what 410 
 
 I S. 
 

mi 
 
 tnu viu.iY IvLNIilU 
 
 LIBRARY