ALCHKMV. 



ALCOHOL. 



of gold, but to the preparing of medicines^, Libavius, Van Helmont, 

 Glauber, and Kunckel. 



To these believers ill the art may be added Bergtuann, n celebrated | 

 chemist of very late date, who, after Bumming up the evidence for .m.l 

 against the possibility and probability of transmutation, observes, 

 rejecting the numerous relation* that have been given by writers of 

 apparent veracity, that, "although most of them are deceptive, ami 

 many uncertain, some bear such character and testimony, that, unless 

 we reject all historical evidence, we must allow them entitled to con- 



The later Peter W.mlfe, who was a Fellow of the Royal Society, and 

 died in 1805. is reported to have been a believer in alchemy. Hi* 

 name is aaaociated with chemical operations on account of the apporntu* 

 which bears his name, but which had been previously described by 

 Glauber. 



The hot person, at least in this country, who professed to convert 

 mercury iiito silver and gold, was Dr. Price of Guildford : he is 

 have convinced some persons of the possibility of the transmutation ; 

 his experiments were to have been repeated before competent judges, 

 but he prevented detection and exposure by destroying himself with 

 laurel water. This happened in 1782. 



For an account of that mysterious substance, the philosophers' stone, 

 by which the wonders of transmutation were worked, and a detail of 

 the process for preparing it, given in the words of an adept, we refer 

 the reader to Dr. Thomson's ' History of Alchemy,' p. 23. 



Dr. Thomson states, that the philosophers' stone, prepared by the 

 elaborate process above referred to, could hardly have been anything 

 else than an amalgam of gold; and " there is no doubt," he adds, " that 

 amalgam of gold, if projected into melted lead or tin, and afterwards 

 cupellated, would leave a portion of gold ; all the gold, of course, that 

 existed previously in the amalgam. It might, therefore, have been 

 employed by impostors to persuade the ignorant that it was really the 

 philosophers' stone; but the alchemists who prejwed the amalgam, 

 could not be ignorant that it contained gold." 



In the ' Memoirs of the Academy of Sciences' for 1772, M. Geoffrey 

 published an account of the various modes in which the frauds of the 

 adepts were carried on ; some of these we shall mention. He observes 

 that, instead of the mineral substances which they pretended to trans- 

 mute, they put oxide (cAaiur) of gold or silver at the bottom of the 

 crucible, the mixture being covered with some powdered crucible and 

 gum-water, or wax, so that it might look like the bottom of the 

 crucible. On other occasions, they made a hole in a piece of charcoal, 

 filled it with powdered gold or silver, and closed the hole with wax ; 

 or they soaked charcoal in a solution of these metals, and threw the 

 charcoal, when powdered, upon the material to be transmuted. They 

 used also small pieces of wood, hollowed at the end, put filings of gold 

 or silver into the cavity, and stopped it with fine sawdust of the same 

 wood, which on burning left the metal in the crucible. Sometimes 

 they whitened gold with mercury, and made it pass for silver or tin ; 

 and the gold, when melted, was exhibited as gold obtained by trans- 

 mutation. They had a solution of nitrate of silver, or of chloride of 

 gold, or an amalgam of gold or silver, which, being adroitly introduced 

 into the crucible, furnished the necessary quantity of metal. A com- 

 mon exhibition was, to dip nails into a liquid, and to take them out 

 apparently half converted into gold : these nails consisted of one-half 

 iron, neatly soldered to the other half, which was gold, and covered 

 with something to conceal the colour, which the liquor removed. 

 Sometimes they had metals made of gold and silver soldered together ; 

 the gold side was whitened with mercury, dipped into some trans- 

 muting liquid, and then heated ; the mercury being dissipated, the 

 gold portion of the metal appeared. 



Bergmann, in his ' Essays,' vol. iii. p. 93 (' History of Chemistry 

 during the Middle Ages'), has given a number of cases in which gold 

 had been supposed to be formed by the use of the philosophers' stone. 

 They were unquestionably the result* of some of the above-mentioned 

 tricks ; but Bergmann states it an his opinion, that some accounts ol 

 transmutation are " entitled to a greater degree of credit " than others. 

 " For doubtless," he adds, " if a person, who has no faith in the changes 

 of alchemintry. *li<mM ..l.l.iin l>y chance a small piece of the philoso- 

 phers' stone, and, on making the experiment alone in his closet , pnmin 

 a quantity of gold heavier than the stone, will it not be difficult to 

 explain in what manner he wax liable to be deceived ? " Before the 

 difficulty is required to be explained, the fact must bo placed on 

 incontestable evidence. 



The question lias sometimes been asked, whether tin 1 l.-tlxmrs of the 

 adept* hare been favourable or otherwise to the program of chemical 

 -v-icnce f Thin question we should be inclined to answer in the ncga- 

 n account of the disrepute into which the jargon of their 

 writings and the frauds of their experiment* must have brought, not 

 only their authors, but the science which they abused. On thin subject 

 Dr Thomson however remarks (' History,' p. 30), " As the alchymist* 

 wwe aamduous workmen, an they mixed all the metals, salt*, &r., will 

 which tlipy were acquainted, in various ways with each other, and sub 

 jectod luch mixtures to the action of heat in close veiwels, their labours 

 were occasionally repaid by the discovery of new substances, posseasec 

 of mnch greater activity than any with which they were previously 

 acquainted. In this way they were led to the discovery of sulphuric- 

 nitric, and hydrochloric acids. These, when known, were made to ac' 



upon the metals; solutions of the metals were o'.i .Mn-d. an<1 this 

 gradually led to the knowledge of various metalline salt* and prepara- 

 hieh wen- introduced with considerable advantage into medicin--. 

 Chus the alchemi-t-. l>y their absurd pursuits, gradually fornn-d a 

 collection of fact*, which led ultimately to the establishment of 

 tine chemistry." It may be also stated in favour of the aMi. 

 .hat phosphorus was discovered by an adept of the name of Brandt, at 

 Hamburg, in 1677 : this he procured from urine, while 1 searching for 

 some substance capable of transmuting silver into gold. 



(iit>lH>n, ' Hex-line and Fall,' voL ii. p. 187, speaking of nlchem> 

 that, " congenial to the avarice of the human heart, it wan studied in 

 China as in Europe, with equal eagenieas, and with equal success. The 

 darkness of the middle ages insured a favourable reception to every 

 ale of wonder; and the revival of learning gave new vigour to li<>| . 

 and suggested more specious arts of deception. Philosophy, with tin- 

 aid of experience, has at length banished the study of alchemy: and 

 the present age, however desirous of riches, is content to seek them l>y 

 the humbler means of commerce and industry." 



A not very successful attempt has lately been made to show that 

 the alchemist* were in reality moral philosophers, who clothed their 

 thoughts in metaphorical language, and that the tran.-forinations they 

 describe refer to mental and not to chemical processes. 



ALCOHOL. (C. H, 0,) Sprit f Wine ; Jf : /tlmte of Kilty! ; Vlnir 

 Alcohol. Alcohol was first discovered as a distinct compound 1>y a 

 physician of Montpelier about 1300, but its true composition w- 

 made known by De Sassure. Alcohol is derived, 1st, from the fermen- 

 tation of saccharine matters, and, 2nd, from the product* of the destruc- 

 tive distillation of coal and other organic substances. It may also be 

 made artificially from it* elements. Practically it is always obtained 

 from the first source. By contact with yeast, grape sugar is trans- 

 formed into alcohol and carbonic acid. 



= 2C,n.O, 



Alcohol. 



Grape Sugar. 



4CO,. 



Carbonic 



Acid. 



The alcohol thus produced is contained in the various fermented 

 liquors, such as beer, wine, wash, &c., greatly diluted with water and 

 mixed also with several other substances. From the latter it is freed 

 by repeated distillation, by which much of the water is also got rid of ; 

 but on account of the chemical affinity existing between alcohol and 

 water, it is not possible to obtain the former free from the latter by 

 simple distillation, though frequently repeated ; the specific gra\ 

 the product is never less than 0'825, and the rectified spirit of wine of 

 commerce and of the 'London Pharmacopoeia' has a specific gravity 

 of 0-835. 



In order to obtain pure or absolute alcohol, other method.- must lc 

 resorted to. According to M. Soemiuering, the water may l>e entirely 

 separated from alcohol by the following process : Put the spirit i: 

 ox's bladder coated with isinglass, and expose it to a temperature of 

 105 to 120 ; the interior of the bladder is moistened by the water of 

 the spirit, and whilst the exterior coat dries, fresh portions of water 

 continue to penetrate the bladder, and to evaporate from its si 

 while but little of the alcohol escapes with it. Spirit put into a w ide- 

 mouthed bottle and tied over with bladder, suffers a Him: 

 tion of the water and concentration of the alcohol. Oeiger and Pla- 

 niava assert, however, that the remaining alcohol still retain* tin 

 cent, of water. Pajot Deschannes proposed to place spirit in a flat 

 vessel beside fragment* of chloride of calcium under a closed receiver ; 

 the air contained in this soon becomes loaded with the vapour rising 

 from the spirituous liquor, the salt combines with the aqueous portion 

 of it, and the alcohol is gradually concentrated; some, however, is 

 lost, being vaporised and condensed with the water. Berzelius, ' Trait*; 

 de Chimie,' t, vi. 448. 



Graham proposes a process upon a similar principle, namely, that of 

 placing a shallow vessel of spirit over another containing coarsely 

 powdered lime, under a bell-glass, upon the plate of an air-pump ; the 

 air is exhausted till the alcohol begins to boil, and the lime absorbs the 

 water only of the vapour which rises. If sulphuric ncid be substituted 

 for lime, then Isith the water and spirit evaporate and are totally 

 absorbed. ' KdiuK 1'hil. Trails.' 1828. 



Although these are interesting processes, yet they aro scarcely appli- 

 cable on an extensive scale. The oest method* de|>cnd upon adding to 

 the spirit some substance which ha affinity for the water, and none or 

 but little for the alcohol ; thus carlxmate of |iotasli is a deliquescent 

 salt, and has consequently a great affinity for water, but unlike most 

 this description, it has no affinity for alcohol, and is totally 

 in.-olulilc in it. When, then, dry carbonate of potash in jxmdcr is 

 put into rectified spirit of wine of s)M-cific gravity 0'835, the water 

 which it contains dissolves the alkaline salt, and forms a dense 

 solution, on which the alcohol float*, not, however, quite free from 

 water, for when separated and distilled, its specific gravity is reduced 

 only to O'SIS, and therefore it still continues to retain about 5 per cent. 

 of water. 



A convenient material for obtaining alcohol, nearly if not quite free 

 f lom water, is sulphate of copper, strongly dried so ax to expel it* water 

 of crystallisation. If strong spirit of wine be digested for three or four 

 days with an equal weight of the dried sulphate, and the mixture be 

 distilled from a water bath, alcohol, absolute or nearly so, will paws into 



