Al'chemy is to modern chemistry what astrology is to astronomy, or legend to history. In the eye of the astrologer, a knowledge of the stars was valuable only as a means of foretelling, or even of influencing, future events. In like manner, the genuine alchemist toiled with his crucibles and alembics, calcining, subliming, distilling, not with a view to discover the chemical properties of substances, as we understand them, but with two grand objects, as illusory as those of the astrologer—to discover, namely, (1) the secret of transmuting the baser metals into gold and silver, and (2) the means of indefinitely prolonging human life.
The word is derived from the Arabic alkīmīa, compounded of the Arabic article and a Greek word chēmīa, used in Diocletian's decree against Egyptian works treating of the chēmīa (transmutation) of gold and silver. The Greek word is now most usually explained to mean 'the Egyptian art,' and derived from the Egyptian name for Egypt, Khmi; but it was ultimately confounded with the true Greek chumeia, pouring, infusion. The latter form, which was possibly, however, the real original of chēmīa, justifies the Renaissance spellings, alchymy and chymistry.
Tradition points to Egypt as the birthplace of the science. Hermes Trismegistus is represented as the father of it; but it should be remembered that the speculations of some of the early Greek philosophers, as of Empedocles, who first named the four elements, pointed in the direction of a rudimentary chemical theory. Zosimus the Theban discovered in sulphuric acid a solvent of the metals, and liberated oxygen from the red oxide of mercury. The students of the 'sacred art' at Alexandria believed in the transmutation of the four elements. The Roman emperor Caligula is said to have instituted experiments for producing gold out of orpiment (sulphuret of arsenic); and in the time of Diocletian, the passion for this pursuit, conjoined with magical arts, had become so prevalent in the empire, that that emperor is said to have ordered all Egyptian works treating of the chemistry of gold and silver to be burnt. For at that time multitudes of books on this art were appearing, written by Alexandrine monks and by hermits, but bearing famous names of antiquity, such as Democritus, Pythagoras, and Hermes.
At a later period, the Arabs, who had enthusiastically adopted Aristotle from the Greeks, appropriated the astrology and alchemy of the Persians and the Jews of Mesopotamia and Arabia; and it is to them that European alchemy is directly traceable. The school of polypharmacy, as it has been called, flourished in Arabia during the califates of the Abbasides. The earliest work of this school now known is the Summa Perfectionis, or 'Summit of Perfection,' composed by Gebir (q.v.) in the 8th century; it is consequently the oldest book on chemistry proper in the world. It contains so much of what sounds very much like jargon in our ears, that Dr Johnson (erroneously) ascribed the origin of the word 'gibberish' to the name of the compiler. Yet when viewed in its true light, it is a wonderful performance. It is a kind of text-book, or collection of all that was then known and believed. It appears that these Arabian polypharmacists had long been engaged in calcining and boiling, dissolving and precipitating, subliming and coagulating chemical substances. They worked with gold and mercury, arsenic and sulphur, salts and acids; and had, in short, become familiar with a large range of what are now called chemicals. Gebir discovered corrosive sublimate, the process of cupellation of gold and silver, and distillation. He taught that there are three elemental chemicals—mercury, sulphur, and arsenic. These substances, especially the first two, seem to have fascinated the thoughts of the alchemists by their potent and penetrating qualities. They saw mercury dissolve gold, the most incorruptible of matters, as water dissolves sugar; and a stick of sulphur presented to hot iron penetrates it like a spirit, and makes it run down in a shower of solid drops, a new and remarkable substance, possessed of properties belonging neither to iron nor to sulphur. The Arabians held that the metals are compound bodies, made up of mercury and sulphur in different proportions. With these very excusable errors in theory, they were genuine practical chemists. They toiled away at the art of making 'many medicines' (polypharmacy) out of the various mixtures and reactions of such chemicals as they knew. They had their pestles and mortars, their crucibles and furnaces, their alembics and aludels, their vessels for infusion, for decoction, for cohabitation, sublimation, fixation, lixiviation, filtration, coagulation, &c. Their scientific creed was transmutation, and their methods were mostly blind gropings; and yet, in this way, they found out many a new body, and invented many a useful process. To the Arab alchemists we owe the terms alcohol, alkali, borax, elixir.
From the Arabs, alchemy found its way through
Spain into Europe generally, and speedily became entangled with the fantastic subtleties of the scholastic philosophy. In the middle ages it was chiefly the monks that occupied themselves with alchemy. Pope John XXII. took great delight in it, but denounced the searchers for gold 'who promise more than they can perform,' and the art was afterwards forbidden by his successor. The earliest authentic works on European alchemy now extant are those of Roger Bacon (1214-94) and Albertus Magnus (1193-1280). Roger Bacon (q.v.), who was acquainted with gunpowder, condemns magic, necromancy, charms, and all such things, but believes in the convertibility of the inferior metals into gold. Still, he does not profess to have ever effected the conversion, an idea which took firm possession of the imagination and, latterly, of the avarice of the middle ages. Their conception was that gold was the perfect metal, and that all other metals were so many removes or deflections from gold, in consequence of arrestment, corruption, or other accidents. Now, though gold, being simply perfect, could not, if mixed with the imperfect, perfect the latter, but would rather share its imperfections; yet, were a substance found many times more perfect than gold, it might well perfect the imperfect. Such a substance would be composed of purest mercury and sulphur, commingled into a solid mass, and matured by wisdom and artificial fire into possibly a thousand thousand times the perfection of the simple body. This was the philosopher's stone which so many devotees of alchemy in the middle ages toiled in vain to fabricate. Roger Bacon followed Gebir in regarding potable gold—that is, gold dissolved in nitro-hydrochloric acid or aqua regia—as the elixir of life. Urging it on the attention of Pope Nicholas IV., he informs his Holiness of an old man who found some yellow liquor (the solution of gold is yellow) in a golden phial, when ploughing one day in Sicily. Supposing it to be dew, he drank it off. He was thereupon transformed into a hale, robust, and highly accomplished youth.—Albertus Magnus (q.v.) had a great mastery of the practical chemistry of his times; he was acquainted with alum, caustic alkali, and the purification of the royal metals by means of lead. In addition to the sulphur-and-mercury theory of the metals, drawn from Gebir, he regarded the element water as still nearer the soul of nature than either of these bodies. He is the first to speak of the affinity of bodies, a term he uses in reference to the action of sulphur on metals.—Thomas Aquinas (q.v.) also wrote on alchemy, and was the first to employ the word Amalgam (q.v.).—Raymond Lully (q.v.) is another great name in the annals of alchemy. He was the first to introduce the use of chemical symbols, his system consisting of a scheme of arbitrary hieroglyphics. He made much of the spirit of wine (the art of distilling spirits would seem to have been then recent), imposing on it the name of aqua vite ardens. In his enthusiasm, he pronounced it the very elixir of life.—Basil Valentine (q.v.) used to get the credit of having, about the end of the 15th century, introduced antimony into medical use. He, it was said, regarded salt, sulphur, and mercury as the three bodies contained in the metals; and he inferred that the philosopher's stone must be a compound of salt, sulphur, and mercury, so pure that its projection on the base metals should be able to work them up into greater and greater purity, bringing them at last to the state of silver and gold. But as it has been proved that 'Basil Valentine' is but an assumed name for Johann Thölde, writing in the middle of the 17th century, the attribution of these views to a writer of the 15th century has brought confusion into this part of the history.
But more famous than all was Paracelsus (q.v.), in whom alchemy proper may be said to have culminated. He held, with Basil Valentine, that the elements of compound bodies were salt, sulphur, and mercury—representing respectively earth, air, and water, fire being already regarded as an imperdurable—but these substances were in his system purely representative. All kinds of matter were reducible under one or other of these typical forms; everything was either a salt, a sulphur, or a mercury, or, like the metals, it was a 'mixt' or compound. There was one element, however, common to the four; a fifth essence or 'quintessence' of creation; an unknown and only true element, of which the four generic principles were nothing but derivative forms or embodiments: in other words, he inculcated the dogma, that there is only one real elementary matter—nobody knows what. This one prime element of things he appears to have considered to be the universal solvent of which the alchemists were in quest, and to express which he introduced the term alcahest. He seems to have had the notion, that if this quintessence or fifth element could be got at, it would prove to be at once the philosopher's stone, the universal medicine, and the irresistible solvent. An often-quoted saying of his is 'Vita ignis, corpus lignum' (Life is the fire, the body the fuel).
After Paracelsus, the alchemists of Europe became divided into two classes. The one class was composed of men of diligence and sense, who devoted themselves to the discovery of new compounds and reactions—practical workers and observers of facts, and the legitimate ancestors of the positive chemists of the era of Lavoisier. The other class took up the visionary, fantastical side of the older alchemy, and carried it to a degree of extravagance before unknown. Instead of useful work, they compiled mystical trash into books, and fathered them on Hermes, Aristotle, Albertus Magnus, Paracelsus, and other really great men. Their language is a farrago of mystical metaphors, full of 'red bridegrooms' and 'lily brides,' 'green dragons,' 'ruby lions,' 'royal baths,' 'waters of life.' The seven metals correspond with the seven planets, the seven cosmical angels, and the seven openings of the head—the eyes, the ears, the nostrils, and the mouth. Silver was Diana, gold was Apollo, iron was Mars, tin was Jupiter, lead was Saturn, and so forth. They talk for ever of the powder of attraction, which drew all men and women after the possessor; of the alkahest or universal solvent, and the grand elixir, which was to confer immortal youth upon the student who should approve himself fit to kiss and quaff the golden draught. There was the great mystery, the mother of the elements, the grandmother of the stars. There was the philosopher's stone, and there was the philosophical stone. The philosophical stone was younger than the elements, yet at her virgin touch the grossest calx (ore) among them all would blush before her into perfect gold. The philosopher's stone, on the other hand, was the first-born of nature, and older than the king of metals. Those who had attained full insight into the arcana of the science were styled Wise; those who were only striving after the light were Philosophers; while the ordinary practisers of the art were called Adepts. It was these visionaries that formed themselves into Rosicrucian Societies and other secret associations. It was also in connection with this mock-alchemy, mixed up with astrology and magic, that quackery and imposture so abounded, as is depicted by Scott in the character of Dousterswivel in the Antiquary. Designing knaves would, for instance, make up large nails, half of iron and half of gold, and lacker them, so that they appeared common nails; and when their credulous and avaricious dupes saw them extract from what seemed plain iron an ingot of gold, they were ready to advance any sum that the knaves pretended to be necessary for pursuing the process on a large scale. It is from this degenerate and effete school that the prevailing notion of alchemy is derived—a notion which is unjust to the really meritorious alchemists who paved the way for genuine chemistry. In 1782 Dr Price of Guildford exhibited to George III. some specimens of gold he affirmed he had made from a red and white powder. Being called upon, as a member of the Royal Society, to repeat his experiments in the presence of two witnesses, after much equivocation he took poison and died (1783). It should be remembered that Robert Boyle believed in the possibility of the alchemistic transmutations; Sir Isaac Newton not merely studied with care the works of the alchemists, but in his earlier years actually laboured in the search for the philosopher's stone.
It is interesting to observe that the leading tenet in the alchemists' creed—namely, the doctrine of the transmutability of other metals into gold and silver—a doctrine which it was at one time thought that modern chemistry had utterly exploded, and which was rejected as an impossibility by Sir Humphry Davy—receives not a little countenance from a variety of facts now coming to light, especially in connection with Allotropy (q.v.). See Kopp's Die Alchemie in älterer und neuerer Zeit, and his Geschichte der Chemie; Hoefler's Histoire de la Chimie; and G. Rodwell's Birth of Chemistry (1874).