The History of Chemistry, Volume 1 (of 2)

by Thomas Thomson

XI.—MISCELLANEOUS OBSERVATIONS.

The ancients seem to have been ignorant of the nature and properties of air, and of all gaseous bodies. Pliny’s account of air consists of a single sentence: “Aër densatur nubibus; furit procellis.” “Air is condensed in clouds, it rages in storms.” Nor is his description of water much more complete, since it consists only of the following phrases: “Aquæ subeunt in imbres, rigescunt in grandines, tumescunt in fluctus, præcipitantur in torrentes.”[95] “Water falls in showers, congeals in hail, swells in waves, and rushes down in torrents.” In the thirty-eighth chapter of the second book, indeed, he professes to treat of air; but the chapter contains merely an enumeration of meteorological phenomena, without once touching upon the nature and properties of air.

Pliny, with all the philosophers of antiquity, admitted the existence of the four elements, fire, air, water, and earth; but though he enumerates these in the fifth chapter of his first book, he never attempts to explain their nature or properties. Earth, among the ancients, had two meanings, namely, the planet on which we live, and the soil upon which vegetables grow. These two meanings still exist in common language. The meaning afterwards given to the term, earth, by the chemists, did not exist in the days of Pliny, or, at least, was unknown to him; a sufficient proof that chemistry, in his time, had made no progress as a science; for some notions respecting the properties and constituents of those supposed four elements must have constituted the very foundation of scientific chemistry.

The ancients were acquainted with none of the acids which at present constitute so numerous a tribe, except vinegar, or acetic acid; and even this acid was not known to them in a state of purity. They knew none of the saline bases, except lime, soda, and potash, and these very imperfectly. Of course the whole tribe of salts was unknown to them, except a very few, which they found ready formed in the earth, or which they succeeded in forming by the action of vinegar on lead and copper. Hence all that extensive and most important branch of chemistry, consisting of the combinations of the acids and bases, on which scientific chemistry mainly depends, must have been unknown to them.

Sulphur occurring native in large quantities, and being remarkable for its easy combustibility, and its disagreeable smell when burning, was known in the very earliest ages. Pliny describes four kinds of sulphur, differing from each other, probably, merely in their purity. These were 1. Sulphur vivum, or apyron. It was dug out of the earth solid, and was doubtless pure, or nearly so. It alone was used in medicine. 2. Gleba—used only by fullers. 3. Egula—used also by fullers. Pliny says, it renders woollen stuffs white and soft. It is obvious from this, that the ancients knew the method of bleaching flannel by the fumes of sulphur, as practised by the moderns. 4. The fourth kind was used only for sulphuring matches.

Sulphur, in Pliny’s time, was found native in the Æolian islands, and in Campania. It is curious that he never mentions Sicily, whence the great supply is drawn for modern manufacture.

In medicine, it seems to have been only used externally by the ancients. It was considered as excellent for removing eruptions. It was used also for fumigating.

The word alumen, which we translate alum, occurs often in Pliny; and is the same substance which the Greeks distinguished by the name of στυπτηρια (stypteria). It is described pretty minutely by Dioscorides, and also by Pliny. It was obviously a natural production, dug out of the earth, and consequently quite different from our alum, with which the ancients were unacquainted. Dioscorides says that it was found abundantly in Egypt; that it was of various kinds, but that the slaty variety was the best. He mentions also many other localities. He says that, for medical purposes, the most valued of all the varieties of alumen were the slaty, the round, and the liquid. The slaty alumen is very white, has an exceedingly astringent taste, a strong smell, is free from stony concretions, and gradually cracks and emits long capillary crystals from these rifts; on which account it is sometimes called trichites. This description obviously applies to a kind of slate-clay, which probably contained pyrites mixed with it of the decomposing kind. The capillary crystals were probably similar to those crystals at present called hair-salt by mineralogists, which exude pretty abundantly from the shale of the coal-beds, when it has been long exposed to the air. Hair-salt differs very much in its nature. Klaproth ascertained by analysis, that the hair-salt from the quicksilver-mines in Idria is sulphate of magnesia, mixed with a small quantity of sulphate of iron.[96] The hair-salt from the abandoned coal-pits in the neighbourhood of Glasgow is a double salt, composed of sulphate of alumina, and sulphate of iron, in definite proportions; the composition being 1 atom protosulphate of iron, 1½ atom sulphate of alumina, 15 atoms water.

I suspect strongly that the capillary crystals from the schistose alumen of Dioscorides were nearly of the same nature.

From Pliny’s account of the uses to which alumen was applied, it is quite obvious that it must have varied very much in its nature. Alumen nigrum was used to strike a black colour, and must therefore have contained iron. It was doubtless an impure native sulphate of iron, similar to many native productions of the same nature still met with in various parts of the world, but not employed; their use having been superseded by various artificial salts, more definite in their nature, and consequently more certain in their application, and at the same time cheaper and more abundant than the native.

The alumen employed as a mordant by the dyers, must have been a sulphate of alumina more or less pure; at least it must have been free from all sulphate of iron, which would have affected the colour of the cloth, and prevented the dyer from accomplishing his object.[97]

What the alumen rotundum was, is not easily conjectured. Dioscorides says, that it was sometimes made artificially; but that the artificial alumen rotundum was not much valued. The best, he says, was full of air-bubbles, nearly white, and of a very astringent taste. It had a slaty appearance, and was found in Egypt or the Island of Melos.

The liquid alumen was limpid, milky, of an equal colour, free from hard concretions, and having a fiery shade of colour.[98] In its nature, it was similar to the alumen candidum; it must therefore have consisted chiefly, at least, of sulphate of alumina.

Bitumen and naphtha were known to the ancients, and used by them to give light instead of oil; they were employed also as external applications in cases of disease, and were considered as having the same virtues as sulphur. It is said, that the word translated salt in the New Testament—“Ye are the salt of the earth: but if the salt have lost his savour, wherewith shall it be salted? It is henceforth good for nothing, but to be cast out, and to be trodden under foot of men”[99]—it is said, that the word salt in this passage refers to asphalt, or bitumen, which was used by the Jews in their sacrifices, and called salt by them. But I have not been able to find satisfactory evidence of the truth of this opinion. It is obvious from the context, that the word translated salt could not have had that meaning among the Jews; because salt never can be supposed to lose its savour. Bitumen, while liquid, has a strong taste and smell, which it loses gradually by exposure to the air, as it approaches more and more to a solid form.

Asphalt was one of the great constituents of the Greek fire. A great bed of it still existing in Albania, supplied the Greeks with this substance. Concerning the nature of the Greek fire, it is clear that many exaggerated and even fabulous statements have been published. The obvious intention of the Greeks being, probably, to make their invention as much dreaded as possible by their enemies. Nitre was undoubtedly one of the most important of its constituents; though no allusion whatever is ever made. We do not know when nitrate of potash, the nitre of the moderns, became known in Europe. It was discovered in the east; and was undoubtedly known in China and India before the commencement of the Christian era. The property of nitre, as a supporter of combustion, could not have remained long unknown after the discovery of the salt. The first person who threw a piece of it upon a red-hot coal would observe it. Accordingly we find that its use in fireworks was known very early in China and India; though its prodigious expansive power, by which it propels bullets with so great and destructive velocity, is a European invention, posterior to the time of Roger Bacon.

The word nitre (רתנ) had been applied by the ancients to carbonate of soda, a production of Egypt, where it is still formed from sea-water, by some unknown process of nature in the marshes near Alexandria. This is evident, not merely from the account given of it by Dioscorides and Pliny; for the following passage, from the Old Testament, shows that it had the same meaning among the Jews: “As he that taketh away a garment in cold weather, is as vinegar upon nitre: so is he that singeth songs to a heavy heart.”[100] Vinegar poured upon saltpetre produces no sensible effect whatever, but when poured upon carbonate of soda, it occasions an effervescence. When saltpetre came to be imported to Europe, it was natural to give it the same name as that applied to carbonate of soda, to which both in taste and appearance it bore some faint resemblance. Saltpetre possessing much more striking properties than carbonate of soda much more attention was drawn to it, and it gradually fixed upon itself the term nitre, at first applied to a different salt. When this change of nomenclature took place does not appear; but it was completed before the time of Roger Bacon, who always applies the term nitrum to our nitrate of potash and never to carbonate of soda.

In the preceding history of the chemical facts known to the ancients, I have taken no notice of a well-known story related of Cleopatra. This magnificent and profligate queen boasted to Antony that she would herself consume a million of sistertii at a supper. Antony smiled at the proposal, and doubted the possibility of her performing it. Next evening a magnificent entertainment was provided, at which Antony, as usual, was present, and expressed his opinion that the cost of the feast, magnificent as it was, fell far short of the sum specified by the queen. She requested him to defer computing till the dessert was finished. A vessel filled with vinegar was placed before her, in which she threw two pearls, the finest in the world, and which were valued at ten millions of sistertii; these pearls were dissolved by the vinegar,[101] and the liquid was immediately drunk by the queen. Thus she made good her boast, and destroyed the two finest pearls in the world.[102] This story, supposing it true, shows that Cleopatra was aware that vinegar has the property of dissolving pearls. But not that she knew the nature of these beautiful productions of nature. We now know that pearls consist essentially of carbonate of lime, and that the beauty is owing to the thin concentric laminæ, of which they are composed.

Nor have I taken any notice of lime with which the ancients were well acquainted, and which they applied to most of the uses to which the moderns put it. Thus it constituted the base of the Roman mortar, which is known to have been excellent. They employed it also as a manure for the fields, as the moderns do. It was known to have a corrosive nature when taken internally; but was much employed by the ancients externally, and in various ways as an application to ulcers. Whether they knew its solubility in water does not appear; though, from the circumstance of its being used for making mortar, this fact could hardly escape them. These facts, though of great importance, could scarcely be applied to the rearing of a chemical structure, as the ancients could have no notion of the action of acids upon lime, or of the numerous salts which it is capable of forming. Phenomena which must have remained unknown till the discovery of the acids enabled experimenters to try their effects upon limestone and quicklime. Not even a conjecture appears in any ancient writer that I have looked into, about the difference between quicklime and limestone. This difference is so great that it must have been remarked by them, yet nobody seems ever to have thought of attempting to account for it. Even the method of burning or calcining lime is not described by Pliny; though there can be no doubt that the ancients were acquainted with it.

Nor have I taken any notice of leather or the method of tanning it. There are so many allusions to leather and its uses by the ancient poets and historians, that the acquaintance of the ancients with it is put out of doubt. But so far as I know, there is no description of the process of tanning in any ancient author whatever.

CHAPTER III.
CHEMISTRY OF THE ARABIANS.

Hitherto I have spoken of Alchymy, or of the chemical manufactures of the ancients. The people to whom scientific chemistry owes its origin are the Arabians. Not that they prosecuted scientific chemistry themselves; but they were the first persons who attempted to form chemical medicines. This they did by mixing various bodies with each other, and applying heat to the mixture in various ways. This led to the discovery of some of the mineral acids. These they applied to the metals, &c., and ascertained the effects produced upon that most important class of bodies. Thus the Arabians began those researches which led gradually to the formation of scientific chemistry. We must therefore endeavour to ascertain the chemical facts for which we are indebted to the Arabians.

When Mahomet first delivered his dogmas to his countrymen they were not altogether barbarous. Possessed of a copious and expressive language, and inhabiting a burning climate, their imaginations were lively and their passions violent. Poetry and fiction were cultivated by them with ardour, and with considerable success. But science and inductive philosophy, had made little or no progress among them. The fatalism introduced by Mahomet, and the blind enthusiasm which he inculcated, rendered them furious bigots and determined enemies to every kind of intellectual improvement. The rapidity with which they overran Asia, Africa, and even a portion of Europe, is universally known. At that period the western world, was sunk into extreme barbarism, and the Greeks, with whom the remains of civilization still lingered, were sadly degenerated from those sages who graced the classic ages. Bent to the earth under the most grinding but turbulent despotism that ever disgraced mankind, and having their understandings sealed up by the most subtle and absurd, and uncompromising superstition, all the energy of mind, all the powers of invention, all the industry and talent, which distinguished their ancestors, had completely forsaken them. Their writers aimed at nothing new or great, and were satisfied with repeating the scientific facts determined by their ancestors. The lamp of science fluttered in its socket, and was on the eve of being extinguished.

Nothing good or great could be expected from such a state of society. It was, therefore, wisely determined by Providence that the Mussulman conquerors, should overrun the earth, sweep out those miserable governors, and free the wretched inhabitants from the trammels of despotism and superstition. As a despotism not less severe, and a superstition still more gloomy and uncompromising, was substituted in their place, it may seem at first sight, that the conquests of the Mahometans brought things into a worse state than they found them. But the listless inactivity, the almost deathlike torpor which had frozen the minds of mankind, were effectually roused. The Mussulmans displayed a degree of energy and activity which have few parallels in the history of the world: and after the conquests of the Mahometans were completed, and the Califs quietly seated upon the greatest and most powerful throne that the world had ever seen; after Almanzor, about the middle of the eighth century, had founded the city of Bagdad, and settled a permanent and flourishing peace, the arts and sciences, which usually accompany such a state of society, began to make their appearance.

That calif founded an academy at Bagdad, which acquired much celebrity, and gradually raised itself above all the other academies in his dominions. A medical college was established there with powers to examine all those persons who intended to devote themselves to the medical profession. So many professors and pupils flocked to this celebrated college, from all parts of the world, that at one time their number amounted to no fewer than six thousand. Public hospitals and laboratories were established to facilitate a knowledge of diseases, and to make the students acquainted with the method of preparing medicines. It was this last establishment which originated with the califs that gave a first beginning to the science of chemistry.

In the thirteenth century the calif Mostanser re-established the academy and the medical college at Bagdad: for both had fallen into decay, and had been replaced by an infinite number of Jewish seminaries. Mostanser gave large salaries to the professors, collected a magnificent library, and established a new school of pharmacy. He was himself often present at the public lectures.

The successor of Mostanser was the calif Haroun-Al-Raschid, the perpetual hero of the Arabian tales. He not only carried his love for the sciences further than his predecessors, but displayed a liberality and a tolerance for religious opinions, which was not quite consistent with Mahometan bigotry and superstition. He drew round him the Syrian Christians, who translated the Greek classics, rewarded them liberally, and appointed them instructors of his Mahometan subjects, especially in medicine and pharmacy. He protected the Christian school of Dschondisabour, founded by the Nestorian Christians, before the time of Mahomet, and still continuing in a flourishing state: always surrounded by literary men, he frequently condescended to take a part in their discussions, and not unfrequently, as might have been expected from his rank, came off victorious.

The most enlightened of all the califs was Almamon, who has rendered his name immortal by his exertions in favour of the sciences. It was during his reign that the Arabian schools came to be thoroughly acquainted with Greek science; he procured the translation of a great number of important works. This conduct inflamed the religious zeal of the faithful, who devoted him to destruction, and to the divine wrath, for favouring philosophy, and in that way diminishing the authority of the Koran. Almamon purchased the ancient classics, from all quarters, and recommended the care of doing so in a particular manner to his ambassadors at the court of the Greek emperors. To Leo, the philosopher, he made the most advantageous offers, to induce him to come to Bagdad; but that philosopher would not listen to his invitation. It was under the auspices of this enlightened prince, that the celebrated attempt was made to determine the size of the earth by measuring a degree of the meridian. The result of this attempt it does not belong to this work to relate.

Almotassem and Motawakkel, who succeeded Almamon, followed his example, favoured the sciences, and extended their protection to men of science who were Christians. Motawakkel re-established the celebrated academy and library of Alexandria. But he acted with more severity than his predecessors with regard to the Christians, who may perhaps have abused the tolerance which they enjoyed.

The other vicars of the prophet, in the different Mahometan states, followed the fine example set them by Almamon. Already in the eighth century the sovereigns of Mogreb and the western provinces of Africa showed themselves the zealous friends of the sciences. One of them called Abdallah-Ebn-Ibadschab rendered commerce and industry flourishing at Tunis. He himself cultivated poetry and drew numerous artists and men of science into his state. At Fez and in Morocco the sciences flourished, especially during the reign of the Edrisites, the last of whom, Jahiah, a prince possessed of genius, sweetness, and goodness, changed his court into an academy, and paid attention to those only who had distinguished themselves by their scientific knowledge.

But Spain was the most fortunate of all the Mahometan states, and had arrived at such a degree of prosperity both in commerce, manufactures, population, and wealth, as is hardly to be credited. The three Abdalrahmans and Alhakem carried, from the eighth to the tenth century, the country subject to the Calif of Cordova to the highest degree of splendour. They protected the sciences, and governed with so much mildness, that Spain was probably never so happy under the dominion of any Christian prince. Alhakem established at Cordova an academy, which for several ages was the most celebrated in the whole world. All the Christians of Western Europe repaired to this academy in search of information. It contained, in the tenth century, a library of 280,000 volumes. The catalogue of this library filled no less than forty-four volumes. Seville, Toledo, and Murcia, had likewise their schools of science and their libraries, which retained their celebrity as long as the dominion of the Moors lasted. In the twelfth century there were seventy public libraries in that part of Spain which belonged to the Mahometans. Cordova had produced one hundred and fifty authors, Almeria fifty-two, and Murcia sixty-two.

The Mahometan states of the east continued also to favour the sciences. An emir of Irak, Adad-El-Daula by name, distinguished himself towards the end of the tenth century by the protection which he afforded to men of science. To him almost all the philosophers of the age dedicated their works. Another emir of Irak, Saif-Ed-Daula, established schools at Kufa and at Bussora, which soon acquired great celebrity. Abou-Mansor-Baharam, established a public library at Firuzabad in Curdistan, which at its very commencement contained 7000 volumes. In the thirteenth century there existed a celebrated school of medicine in Damascus. The calif Malek-Adel endowed it richly, and was often present at the lectures with a book under his arm.

Had the progress of the sciences among the Arabians been proportional to the number of those who cultivated them, we might hail the Saracens as the saviours of literature during the dark and benighted ages of Christianity; but we must acknowledge with regret, that notwithstanding the enlightened views of the califs, notwithstanding the multiplicity of academies and libraries, and the prodigious number of writers, the sciences received but little improvement from the Arabians. There are very few Arabian writers in whose works we find either philosophical ideas, successful researches, new facts, or great and new and important truths. How, indeed, could such things be expected from a people naturally hostile to mental exertion; professing a religion which stigmatizes all exercise of the judgment as a crime, and weighed down by the heavy yoke of despotism? It was the religion of the Arabians, and the despotism of their princes, that opposed the greatest obstacles to the progress of the sciences, even during the most flourishing period of their civilization.[103] Fortunately chemistry was the branch of science least obnoxious to the religious prejudices of the Mahometans. It was in it, therefore, that the greatest improvements were made: of these improvements it will be requisite now to endeavour to give the reader some idea. Astrology and alchymy, they both derived from the Greeks: neither of them were inconsistent with the taste of the nation—neither of them were anathematized by the Mahometan creed, though Islamism prohibited magic and all the arts of divination. Alchymy may have suggested the chemical processes—but the Arabians applied them to the preparation of medicines, and thus opened a new and most copious source of investigation.

The chemical writings of the Arabians which I have had an opportunity of seeing and perusing in a Latin dress, being ignorant of the original language in which they were written, are those of Geber and Avicenna.

Geber, whose real name was Abou-Moussah-Dschafar-Al-Soli, was a Sabean of Harran, in Mesopotamia, and lived during the eighth century. Very little is known respecting the history of this writer, who must be considered as the patriarch of chemistry. Golius, professor of the oriental languages in the University of Leyden, made a present of Geber’s work in manuscript to the public library. He translated it into Latin, and published it in the same city in folio, and afterwards in quarto, under the title of “Lapis Philosophorum.”[104] It was translated into English by Richard Russel in 1678, under the title of, “The Works of Geber, the most famous Arabian Prince and Philosopher.”[105] The works of Geber, so far as they appeared in Latin or English, consist of four tracts. The first is entitled, “Of the Investigation or Search of Perfection.” The second is entitled, “Of the Sum of Perfection, or of the perfect Magistery.” The third, “Of the Invention of Verity or Perfection.” And the last, “Of Furnaces, &c.; with a Recapitulation of the Author’s Experiments.”

The object of Geber’s work is to teach the method of making the philosopher’s stone, which he distinguishes usually by the name of medicine of the third class. The whole is in general written with so much plainness, that we can understand the nature of the substances which he employed, the processes which he followed, and the greater number of the products which he obtained. It is, therefore, a book of some importance, because it is the oldest chemical treatise in existence,[106] and because it makes us acquainted with the processes followed by the Arabians, and the progress which they had made in chemical investigations. I shall therefore lay before the reader the most important facts contained in Geber’s work.

1. He considered all the metals as compounds of mercury and sulphur: this opinion did not originate with him. It is evident from what he says, that the same notion had been adopted by his predecessors—men whom he speaks of under the title of the ancients.

2. The metals with which he was acquainted were gold, silver, copper, iron, tin, and lead. These are usually distinguished by him under the names of Sol, Luna, Venus, Mars, Jupiter, and Saturn. Whether these names of the planets were applied to the metals by Geber, or only by his translators, I cannot say; but they were always employed by the alchymists, who never designated the metals by any other appellations.

3. Gold and silver he considered as perfect metals; but the other four were imperfect metals. The difference between them depends, in his opinion, partly upon the proportions of mercury and sulphur in each, and partly upon the purity or impurity of the mercury and sulphur which enters into the composition of each.

Gold, according to him, is created of the most subtile substance of mercury and of most clear fixture, and of a small substance of sulphur, clean and of pure redness, fixed, clear, and changed from its own nature, tinging that; and because there happens a diversity in the colours of that sulphur, the yellowness of gold must needs have a like diversity.[107] His evidence that gold consisted chiefly of mercury, is the great ease with which mercury dissolves gold. For mercury, in his opinion, dissolves nothing that is not of its own nature. The lustre and splendour of gold is another proof of the great proportion of mercury which it contains. That it is a fixed substance, void of all burning sulphur, he thinks evident by every operation in the fire, for it is neither diminished nor inflamed. His other reasons are not so intelligible.[108]

Silver, like gold, is composed of much mercury and a little sulphur; but in the gold the sulphur is red; whereas the sulphur that goes to the formation of silver is white. The sulphur in silver is also clean, fixed, and clear. Silver has a purity short of that of gold, and a more gross inspissation. The proof of this is, that its parts are not so condensed, nor is it so fixed as gold; for it may be diminished by fire, which is not the case with gold.[109]

Iron is composed of earthy mercury and earthy sulphur, highly fixed, the latter in by far the greatest quantity. Sulphur, by the work of fixation, more easily destroys the easiness of liquefaction than mercury. Hence the reason why iron is not fusible, as is the case with the other metals.[110]

Sulphur not fixed melts sooner than mercury; but fixed sulphur opposes fusion. What contains more fixed sulphur, more slowly admits of fusion than what partakes of burning sulphur, which more easily and sooner flows.[111]

Copper is composed of sulphur unclean, gross and fixed as to its greater part; but as to its lesser part not fixed, red, and livid, in relation to the whole not overcoming nor overcome and of gross mercury.[112]

When copper is exposed to ignition, you may discern a sulphureous flame to arise from it, which is a sign of sulphur not fixed; and the loss of the quantity of it by exhalation through the frequent combustion of it, shows that it has fixed sulphur. This last being in abundance, occasions the slowness of its fusion and the hardness of its substance. That copper contains red and unclean sulphur, united to unclean mercury, is, he thinks, evident, from its sensible qualities.[113]

Tin consists of sulphur of small fixation, white with a whiteness not pure, not overcoming but overcome, mixed with mercury partly fixed and partly not fixed, white and impure.[114] That this is the constitution of tin he thinks evident; for when calcined, it emits a sulphureous stench, which is a sign of sulphur not fixed: it yields no flame, not because the sulphur is fixed, but because it contains a great portion of mercury. In tin there is a twofold sulphur and also a twofold mercury. One sulphur is less fixed, because in calcining it gives out a stench as sulphur. The fixed sulphur continues in the tin after it is calcined. He thinks that the twofold mercury in tin is evident, from this, that before calcination it makes a crashing noise when bent, but after it has been thrice calcined, that crashing noise can no longer be perceived.[115] Geber says, that if lead be washed with mercury, and after its washing melted in a fire not exceeding the fire of its fusion, a portion of the mercury will remain combined with the lead, and will give it the crashing noise and all the qualities of tin. On the other hand, you may convert tin into lead. By manifold repetition of its calcination, and the administration of fire convenient for its reduction, it is turned into lead.[116]

Lead, in Geber’s opinion, differs from tin only in having a more unclean substance commixed of the two more gross substances, sulphur and mercury. The sulphur in it is burning and more adhesive to the substance of its own mercury, and it has more of the substance of fixed sulphur in its composition than tin has.[117]

Such are the opinions which Geber entertained respecting the composition of the metals. I have been induced to state them as nearly in his own words as possible, and to give the reasons which he has assigned for them, even when his facts were not quite correct, because I thought that this was the most likely way of conveying to the reader an accurate notion of the sentiments of this father of the alchymists, upon the very foundation of the whole doctrine of the transmutation of metals. He was of opinion that all the imperfect metals might be transformed into gold and silver, by altering the proportions of the mercury and sulphur of which they are composed, and by changing the nature of the mercury and sulphur so as to make them the same with the mercury and sulphur which constitute gold and silver. The substance capable of producing these important changes he calls sometimes the philosopher’s stone, but generally the medicine. He gives the method of preparing this important magistery, as he calls it. But it is not worth while to state his process, because he leaves out several particulars, in order to prevent the foolish from reaping any benefit from his writings, while at the same time those readers who possess the proper degree of sagacity will be able, by studying the different parts of his writings, to divine the nature of the steps which he omits, and thus profit by his researches and explanations. But it will be worth while to notice the most important of his processes, because this will enable us to judge of the state of chemistry in his time.

4. In his book on furnaces, he gives a description of a furnace proper for calcining metals, and from the fourteenth chapter of the fourth part of the first book of his Sum of Perfection, it is obvious that the method of calcining or oxidizing iron, copper, tin, and lead, and also mercury and arsenic were familiarly known to him.

He gives a description of a furnace for distilling, and a pretty minute account of the glass or stoneware, or metallic aludel and alembic, by means of which the process was conducted. He was in the habit of distilling by surrounding his aludel with hot ashes, to prevent it from being broken. He was acquainted also with the water-bath. These processes were familiar to him. The description of the distillation of many bodies occurs in his work; but there is not the least evidence that he was acquainted with ardent spirits. The term spirit occurs frequently in his writings, but it was applied to volatile bodies in general, and in particular to sulphur and white arsenic, which he considered as substances very similar in their properties. Mercury also he considered as a spirit.

The method of distilling per descensum, as is practised in the smelting of zinc, was also known to him. He describes an apparatus for the purpose, and gives several examples of such distillations in his writings.

He gives also a description of a furnace for melting metals, and mentions the vessels in which such processes were conducted. He was acquainted with crucibles; and even describes the mode of making cupels, nearly similar to those used at present. The process of cupellating gold and silver, and purifying them by means of lead, is given by him pretty minutely and accurately: he calls it cineritium, or at least that is the term used by his Latin translator.

He was in the habit of dissolving salts in water and acetic acid, and even the metals in different menstrua. Of these menstrua he nowhere gives any account; but from our knowledge of the properties of the different metals, and from some processes which he notices, it is easy to perceive what his solvents must have been; namely, the mineral acids which were known to him, and to which there is no allusion whatever in any preceding writer that I have had an opportunity of consulting. Whether Geber was the discoverer of these acids cannot be known, as he nowhere claims the discovery: indeed his object was to slur over these acids, as much as possible, that their existence, or at least their remarkable properties, might not be suspected by the uninitiated. It was this affectation of secrecy and mystery that has deprived the earliest chemists of that credit and reputation to which they would have been justly entitled, had their discoveries been made known to the public in a plain and intelligible manner.

The mode of purifying liquids by filtration, and of separating precipitates from liquids by the same means, was known to Geber. He called the process distillation through a filter.

Thus the greater number of chemical processes, such as they were practised almost to the end of the eighteenth century, were known to Geber. If we compare his works with those of Dioscorides and Pliny, we shall perceive the great progress which chemistry or rather pharmacy had made. It is more than probable that these improvements were made by the Arabian physicians, or at least by the physicians who filled the chairs in the medical schools, which were under the protection of the califs: for as no notice is taken of these processes by any of the Greek or Roman writers that have come down to us, and as we find them minutely described by the earliest chemical writers among the Arabians, we have no other alternative than to admit that they originated in the east.

I shall now state the different chemical substances or preparations which were known to Geber, or which he describes the method of preparing in his works.

1. Common salt. This substance occurring in such abundance in the earth, and being indispensable as a seasoner of food, was known from the earliest ages. But Geber describes the method which he adopted to free it from impurities. It was exposed to a red heat, then dissolved in water, filtered, crystallized by evaporation, and the crystals being exposed to a red heat, were put into a close vessel, and kept for use.[118] Whether the identity of sal-gem (native salt) and common salt was known to Geber is nowhere said. Probably not, as he gives separate directions for purifying each.

2. Geber gives an account of the two fixed alkalies, potash and soda, and gives processes for obtaining them. Potash was obtained by burning cream of tartar in a crucible, dissolving the residue in water, filtering the solution, and evaporating to dryness.[119] This would yield a pure carbonate of potash.

Carbonate of soda he calls sagimen vitri, and salt of soda. He mentions plants which yield it when burnt, points out the method of purifying it, and even describes the method of rendering it caustic by means of quicklime.[120]

3. Saltpetre, or nitrate of potash, was known to him; and Geber is the first writer in whom we find an account of this salt. Nothing is said respecting its origin; but there can be little doubt that it came from India, where it was collected, and known long before Europeans were acquainted with it. The knowledge of this salt was probably one great cause of the superiority of the Arabians over Europeans in chemical knowledge; for it enabled them to procure nitric acid, by means of which they dissolved all the metals known in their time, and thus acquired a knowledge of various important saline compounds, which were of considerable importance.

There is a process for preparing saltpetre artificially, in several of the Latin copies of Geber, though it does not appear in our English translation. The method was to dissolve sagimen vitri, or carbonate of soda, in aqua fortis, to filter and crystallize by evaporation.[121] If this process be genuine, it is obvious that Geber must have been acquainted with nitrate of soda; but I have some doubts about the genuineness of the passage, because the term aqua fortis occurs in it. Now this term occurs nowhere else in Geber’s work: even when he gives the process for procuring nitric acid, he calls it simply water; but observes, that it is a water possessed of much virtue, and that it constitutes a precious instrument in the hands of the man who possesses sagacity to use it aright.

4. Sal ammoniac was known to Geber, and seems to have been quite common in his time. There is no evidence that it was known to the Greeks or Romans, as neither Dioscorides nor Pliny make any allusion to it. The word in old books is sometimes sal armoniac, sometimes sal ammoniac. It is supposed to have been brought originally from the neighbourhood of the temple of Jupiter Ammon: but had this been the case, and had it occurred native, it could scarcely have been unknown to the Romans, under whose dominions that part of Africa fell. In the writings of the alchymists, sal ammoniac is mentioned under the following whimsical names: Anima sensibilis,
Aqua duorum fratrum ex sorore,
Aquila,
Lapis aquilinis,
Cancer,
Lapis angeli conjungentis,
Sal lapidum,
Sal alocoph.

Geber not only knew sal ammoniac, but he was aware of its volatility; and gives various processes for subliming it, and uses it frequently to promote the sublimation of other bodies, as of oxides of iron and copper. He gives also a method of procuring it from urine, a liquid which, when allowed to run into putrefaction, is known to yield it in abundance. Sal ammoniac was much used by Geber, in his various processes to bring the inferior metals to a state of greater perfection. By adding it or common salt to aqua fortis, he was enabled to dissolve gold, which certainly could not be accomplished in the time of Dioscorides or Pliny. The description, indeed, of Geber’s process for dissolving gold is left on purpose in a defective state; but an attentive reader will find no great difficulty in supplying the defects, and thus understanding the whole of the process.

5. Alum, precisely the same as the alum of the moderns, was familiarly known to Geber, and employed by him in his processes. The manufacture of this salt, therefore, had been discovered between the time when Pliny composed his Natural History and the eighth century, when Geber wrote; unless we admit that the mode of making it had been known to the Tyrian dyers, but that they had kept the secret so well, that no suspicion of its existence was entertained by the Greeks and Romans. That they employed alumina as a mordant in some of their dyes, is evident; but there is no proof whatever that alum, in the modern sense of the word, was known to them.

Geber mentions three alums which he was in the habit of using; namely, icy alum, or Rocca alum; Jamenous alum, or alum of Jameni, and feather alum. Rocca, or Edessa, in Syria, is admitted to have been the place where the first manufactory of alum was established; but at what time, or by whom, is quite unknown: we know only that it must have been posterior to the commencement of the Christian era, and prior to the eighth century, when Geber wrote. Jameni must have been another locality where, at the time of Geber, a manufactory of alum existed. Feather alum was undoubtedly one of the native impure varieties of alum, known to the Greeks and Romans. Geber was in the habit of distilling alum by a strong heat, and of preserving the water which came over as a valuable menstruum. If alum be exposed to a red heat in glass vessels, it will give out a portion of sulphuric acid: hence water distilled from alum by Geber was probably a weak solution of sulphuric acid, which would undoubtedly act powerfully as a solvent of iron, and of the alkaline carbonates. It was probably in this way that he used it.

6. Sulphate of iron or copperas, as it is called (cuperosa), in the state of a crystalline salt, was well known to Geber, and appears in his time to have been manufactured.

7. Baurach, or borax, is mentioned by him, but without any description by which we can know whether or not it was our borax: the probability is that it was. Both glass and borax were used by him when the oxides of metals were reduced by him to the metallic state.

8. Vinegar was purified by him by distilling it over, and it was used as a solvent in many of his processes.

9. Nitric acid was known to him by the name of dissolving water. He prepared it by putting into an alembic one pound of sulphate of iron of Cyprus, half a pound of saltpetre, and a quarter of a pound of alum of Jameni: this mixture was distilled till every thing liquid was driven over. He mentions the red fumes which make their appearance in the alembic during the process.[122] This process, though not an economical one, would certainly yield nitric acid; and it is remarkable, because it is here that we find the first hint of the knowledge of chemists of this most important acid, without which many chemical processes of the utmost importance could not be performed at all.

10. This acid, thus prepared, he made use of to dissolve silver: the solution was concentrated till the nitrate of silver was obtained by him in a crystallized state. This process is thus described by him: “Dissolve silver calcined in solutive water (nitric acid), as before; which being done, coct it in a phial with a long neck, the orifice of which must be left unstopped, for one day only, until a third part of the water be consumed. This being effected, set it with its vessel in a cold place, and then it is converted into small fusible stones, like crystal.”[123]

11. He was in the habit also of dissolving sal ammoniac in this nitric acid, and employing the solution, which was the aqua regia of the old chemists, to dissolve gold.[124] He assures us that this aqua regia would dissolve likewise sulphur and silver. The latter assertion is erroneous. But sulphur is easily converted into sulphuric acid by the action of aqua regia, and of course it disappears or dissolves.

12. Corrosive sublimate is likewise described by Geber in a very intelligible manner. His method of preparing it was as follows: “Take of mercury one pound, of dried sulphate of iron two pounds, of alum calcined one pound, of common salt half a pound, and of saltpetre a quarter of a pound: incorporate altogether by trituration and sublime; gather the white, dense, and ponderous portions which shall be found about the sides of the vessel. If in the first sublimation you find it turbid or unclean (which may happen by reason of your own negligence), sublime a second time with the same fuses.”[125] Still more minute directions are given in other parts of the work: we have even some imperfect account of the properties of corrosive sublimate.

13. Corrosive sublimate is not the only preparation of mercury mentioned by Geber. He informs us that when mercury is combined with sulphur it assumes a red colour, and becomes cinnabar.[126] He describes the affinities of mercury for the different metals. It adheres easily to three metals; namely, lead, tin, and gold; to silver with more difficulty. To copper with still more difficulty than to silver; but to iron it unites in nowise unless by artifice.[127] This is a tolerably accurate account of the matter. He says, that mercury is the heaviest body in nature except gold, which is the only metal that will sink in it.[128] Now this was true, applied to all the substances known when Geber lived.

He gives an account of the method of forming the peroxide of mercury by heat; that variety of it formerly distinguished by the name of red precipitati per se. “Mercury,” he says, “is also coagulated by long and constant retention in fire, in a glass vessel with a very long neck and round belly; the orifice of the neck being kept open, that the humidity may vanish thereby.”[129] He gives another process for preparing this oxide, possible, perhaps, though certainly requiring very cautious regulation of the fire. “Take,” says he, “of mercury one pound, of vitriol (sulphate of iron) rubified two pounds, and of saltpetre one pound. Mortify the mercury with these, and then sublime it from rock alum and saltpetre in equal weights.”[130]

14. Geber was acquainted with several of the compounds of metals with sulphur. He remarks that sulphur when fused with metals increases their weight.[131] Copper combined with sulphur becomes yellow, and mercury red.[132] He knew the method of dissolving sulphur in caustic potash, and again precipitating it by the addition of an acid. His process is as follows: “Grind clear and gummose sulphur to a most subtile powder, which boil in a lixivium made of ashes of heartsease and quicklime, gathering from off the surface its oleaginous combustibility, until it be discerned to be clear. This being done, stir the whole with a stick, and then warily take off that which passeth out with the lixivium, leaving the more gross parts in the bottom. Permit that extract to cool a little, and upon it pour a fourth part of its own quantity of distilled vinegar, and then will the whole suddenly be congealed as milk. Remove as much of the clear lixivium as you can; but dry the residue with a gentle fire and keep it.”[133]

15. It would appear from various passages in Geber’s works that he was acquainted with arsenic in the metallic state. He frequently mentions its combustibility, and considers it as the compeer of sulphur. And in his book on Furnaces, chapter 25 (or 28 in some copies), he expressly mentions metallic arsenic (arsenicum metallinum), in a preparation not very intelligible, but which he considered of great importance. The white oxide of arsenic or arsenious acid, was obviously well known to him. He gives more than one process for obtaining it by sublimation.[134] He observes in his Sum of Perfection, book i. part iv. chap. 2, which treats of sublimation, “Arsenic, which before its sublimation was evil and prone to adustion, after its sublimation, suffers not itself to be inflamed; but only resides without inflammation.”

Geber states the fact, that when arsenic is heated with copper that metal becomes white.[135] He gives also a process by which the white arseniate of iron is obviously made. “Grind one pound of iron filings with half a pound of sublimed arsenic (arsenious acid). Imbibe the mixture with the water of saltpetre, and salt-alkali, repeating this imbibation thrice. Then make it flow with a violent fire, and you will have your iron white. Repeat this labour till it flow sufficiently with peculiar dealbation.”[136]

16. He mentions oxide of copper under the name of æs ustum, the red oxide of iron under the name of crocus of iron. He mentions also litharge and red lead.[137] But as all these substances were known to the Greeks and Romans, it is needless to enter into any particular details.

17. I am not sure what substance Geber understood by the word marchasite. It was a substance which must have been abundant, and in common use, for he refers to it frequently, and uses it in many of his processes; but he nowhere informs us what it is. I suspect it may have been sulphuret of antimony, which was certainly in common use in Asia long before the time of Geber. But he also makes mention of antimony by name, or at least the Latin translator has made use of the word antimonium. When speaking of the reduction of metals after heating them with sulphur, he says, “The reduction of tin is converted into clear antimony; but of lead, into a dark-coloured antimony, as we have found by proper experience.”[138] It is not easy to conjecture what meaning the word antimony is intended to convey in this passage. In another passage he says, “Antimony is calcined, dissolved, clarified, congealed, and ground to powder, so it is prepared.”[139]

18. Geber’s description of the metals is tolerably accurate, considering the time when he wrote. As an example I shall subjoin his account of gold. “Gold is a metallic body, yellow, ponderous, mute, fulged, equally digested in the bowels of the earth, and very long washed with mineral water; under the hammer extensible, fusible, and sustaining the trial of the cupel and cementation.”[140] He gives an example of copper being changed into gold. “In copper-mines,” he says, “we see a certain water which flows out, and carries with it thin scales of copper, which (by a continual and long-continued course) it washes and cleanses. But after such water ceases to flow, we find these thin scales with the dry sand, in three years time to be digested with the heat of the sun; and among these scales the purest gold is found: therefore we judge those scales were cleansed by the benefit of the water, but were equally digested by heat of the sun, in the dryness of the sand, and so brought to equality.”[141] Here we have an example of plausible reasoning from defective premises. The gold grains doubtless existed in the sand before, while the scales of copper in the course of three years would be oxidized and converted into powder, and disappear, or at least lose all their metallic lustre.

Such are the most remarkable chemical facts which I have observed in the works of Geber. They are so numerous and important, as to entitle him with some justice to the appellation of the father and founder of chemistry. Besides the metals, sulphur and salt, with which the Greeks and Romans were acquainted, he knew the method of preparing sulphuric acid, nitric acid, and aqua regia. He knew the method of dissolving the metals by means of these acids, and actually prepared nitrate of silver and corrosive sublimate. He was acquainted with potash and soda, both in the state of carbonates and caustic. He was aware that these alkalies dissolve sulphur, and he employed the process to obtain sulphur in a state of purity.

But notwithstanding the experimental merit of Geber, his spirit of philosophy did not much exceed that of his countrymen. He satisfied himself with accounting for phenomena by occult causes, as was the universal custom of the Arabians; a practice quite inconsistent with real scientific progress. That this was the case will appear from the following passage, in which Geber attempts to give an explanation of the properties of the great elixir or philosopher’s stone: “Therefore, let him attend to the properties and ways of action of the composition of the greater elixir. For we endeavour to make one substance, yet compounded and composed of many, so permanently fixed, that being put upon the fire, the fire cannot injure; and that it may be mixed with metals in flux and flow with them, and enter with that which in them is of an ingressible substance, and be fermented with that which in them is of a permixable substance; and be consolidated with that which in them is of a consolidable substance; and be fixed with that which in them is of a fixable substance; and not be burnt by those things which burn not gold and silver; and take away consolidation and weights with due ignition.”[142]

The next Arabian whose name I shall introduce into this history, is Al-Hassain-Abou-Ali-Ben-Abdallah-Ebn-Sina, surnamed Scheik Reyes, or prince of physicians, vulgarly known by the name of Avicenna. Next to Aristotle and Galen, his reputation was the highest, and his authority the greatest of all medical practitioners; and he reigned paramount, or at least shared the medical sceptre till he was hurled from his throne by the rude hands of Paracelsus.

Avicenna was born in the year 978, at Bokhara, to which place his father had retired during the emirate of the calif Nuhh, one of the sons of the celebrated Almansor. Ali, his father, had dwelt in Balkh, in the Chorazan. After the birth of Avicenna he went to Asschena in Bucharia, where he continued to live till his son had reached his fifteenth year. No labour nor expense was spared on the education of Avicenna, whose abilities were so extraordinary that he is said to have been able to repeat the whole Koran by heart at the age of ten years. Ali gave him for a master Abou-Abdallah-Annatholi, who taught him grammar, dialectics, the geometry of Euclid, and the astronomy of Ptolemy. But Avicenna quitted his tuition because he could not give him the solution of a problem in logic. He attached himself to a merchant, who taught him arithmetic, and made him acquainted with the Indian numerals from which our own are derived. He then undertook a journey to Bagdad, where he studied philosophy under the great Peripatician, Abou-Nasr-Alfarabi, a disciple of Mesue the elder. At the same time he applied himself to medicine, under the tuition of the Nestorian, Abou-Sahel-Masichi. He informs us himself that he applied with an extraordinary ardour to the study of the sciences. He was in the habit of drinking great quantities of liquids during the night, to prevent him from sleeping; and he often obtained in a dream a solution of those problems at which he had laboured in vain while he was awake. When the difficulties to be surmounted appeared to him too great, he prayed to God to communicate to him a share of his wisdom; and these prayers, he assures us, were never offered in vain. The metaphysics of Aristotle was the only book which he could not comprehend, and after reading them over forty times, he threw them aside with great anger at himself.

Already, at the age of sixteen, he was a physician of eminence; and at eighteen he performed a brilliant cure on the calif Nuhh, which gave him such celebrity that Mohammed, Calif of Chorazan, invited him to his palace; but Avicenna rather chose to reside at Dschordschan, where he cured the nephew of the calif Kabus of a grievous distemper.

Afterwards he went to Ray, where he was appointed physician to Prince Magd-Oddaula. Here he composed a dictionary of the sciences. Sometime after this he was raised to the dignity of vizier at Hamdan; but he was speedily deprived of his office and thrown into prison for having favoured a sedition. While incarcerated he wrote many works on medicine and philosophy. By-and-by he was set at liberty, and restored to his dignity; but after the death of his protector, Schems-Oddaula, being afraid of a new attempt to deprive him of his liberty, he took refuge in the house of an apothecary, where he remained long concealed and completely occupied with his literary labours. Being at last discovered he was thrown into the castle of Berdawa, where he was confined for four months. At the end of that time a fortunate accident enabled him to make his escape, in the disguise of a monk. He repaired to Ispahan, where he lived much respected at the court of the calif Ola-Oddaula. He did not live to a great age, because he had worn out his constitution by too free an indulgence of women and wine. Having been attacked by a violent colic, he caused eight injections, prepared from long pepper, to be thrown up in one day. This excessive use of so irritating a remedy, occasioned an excoriation of the intestines, which was followed by an attack of epilepsy. A journey to Hamdan, in company with the calif, and the use of mithridate, into which his servant by mistake had put too much opium, contributed still further to put an end to his life. He had scarcely arrived at the town when he died in the fifty-eighth year of his age, in the year 1036.

Avicenna was the author of the immense work entitled “Canon,” which was translated into Latin, and for five centuries constituted the great standard, the infallible guide, the confession of faith of the medical world. All medical knowledge was contained in it; and nothing except what was contained in it was considered by medical men as of any importance. When we take a view of the Canon, and compare it with the writings of the Greeks, and even of the Arabians, that preceded it, we shall find some difficulty in accounting for the unbounded authority which he acquired over the medical world, and for the length of time during which that authority continued.

But it must be remembered, that Avicenna’s reign occupies the darkest and most dreary period of the history of the human mind. The human race seems to have been asleep, and the mental faculties in a state of complete torpor. Mankind, accustomed in their religious opinions to obey blindly the infallible decisions of the church, and to think precisely as the church enjoined them to think, would naturally look for some means to save them the trouble of thinking on medical subjects; and this means they found fortunately in the canons of Avicenna. These canons, in their opinion, were equally infallible with the decisions of the holy father, and required to be as implicitly obeyed. The whole science of medicine was reduced to a simple perusal of Avicenna’s Canon, and an implicit adherence to his rules and directions.

When we compare this celebrated work with the medical writings of the Greeks, and even of the Arabians, the predecessors of Avicenna, we shall be surprised that it contains little or nothing which can be considered as original; the whole is borrowed from the writings of Galen, or Ætius, or Rhazes: scarcely ever does he venture to trust his own wings, but rests entirely on the sagacity of his Greek and Arabian predecessors. Galen is his great guide; or, if he ever forsake him, it is to place himself under the direction of Aristotle.

The Canon contains a collection of most of the valuable information contained in the writings of the ancient Greek physicians, arranged, it must be allowed, with great clearness. The Hhawi of Razes is almost as complete; but it wants the lucidus ordo which distinguishes the Canon of Avicenna. I conceive that the high reputation which Avicenna acquired, was owing to the care which he bestowed upon his arrangement. He was undoubtedly a man of abilities, but not of inventive genius. There is little original matter in the Canon. But the physicians in the west, while Avicenna occupied the medical sceptre, had no opportunity of judging of the originality of their oracle, because they were unacquainted with the Greek language, and could not therefore consult the writings of Galen or Ætius, except through the corrupt medium of an Arabian version.

But it is not the medical reputation of Avicenna that induced me to mention his name here. Like all the Arabian physicians, he was also a chemist; and his chemical tracts having been translated into Latin, and published in Western Europe, we are enabled to judge of their merit, and to estimate the effect which they may have had upon the progress of chemistry. The first Latin translation of the chemical writings of Avicenna was published at Basil in 1572; they consist of two separate books; the first, under the name of “Porta Elementorum,” consists of a dialogue between a master and his pupil, respecting the mysteries of Alchymy. He gives an account of the four elements, fire, air, water, earth, and gives them their usual qualities of dry, moist, hot, and cold. He then treats of air, which, he says, is the food of fire, of water, of honey, of the mutual conversion of the elements into each other; of milk and cheese, of the mixture of fire and water, and that all things are composed of the four elements. There is nothing in this tract which has any pretension to novelty; he merely retails the opinions of the Greek philosophers.

The other treatise is much larger, and professes to teach the whole art of alchymy; it is divided into ten parts, entitled “Dictiones.” The first diction treats of the philosopher’s stone in general; the second diction treats of the method of converting light things into heavy, hard things into soft; of the mutation of the elements; and of some other particulars of a nature not very intelligible. The third diction treats of the formation of the elixir; and the same subject is continued in the fourth.

The fifth diction is one of the most important in the whole treatise; it is in general intelligible, which is more than can be said of those that precede it. This diction is divided into twenty-eight chapters: the first chapter treats of copper, which, he says, is of three kinds; permenian copper, natural copper, and Navarre copper. But of these three varieties he gives no account whatever; though he enlarges a good deal on the qualities of copper—not its properties, but its supposed medicinal action. It is hot and dry, he says, but in the calx of it there is humidity. His account of the composition of copper is the same with that of Geber.

The second chapter treats of lead, the third of tin, and in the remaining chapters he treats successively of brass, iron, gold, silver, marcasite, sulphuret of antimony, which is distinguished by the name of alcohol; of soda, which he says is the juice of a plant called sosa. And he gives an unintelligible process by which it is extracted from that plant, without mentioning a syllable about the combustion to which it is obvious that it must have been subjected.

In the twelfth chapter he treats of saltpetre, which, he says, is brought from Sicily, from India, from Egypt, and from Herminia. He describes several varieties of it, but mentions nothing about its characteristic property of deflagrating upon burning coals. He then treats successively of common salt, of sal-gem, of vitriol, of sulphur, of orpiment, and of sal ammoniac, which, he says, comes from Egypt, from India, and from Forperia. In the nineteenth and subsequent chapters he treats of aurum vivum, of hair, of urine, of eggs, of blood, of glass, of white linen, of horse-dung, and of vinegar.

The sixth diction, in thirty-three chapters, treats of the calcination of the metals, of sublimation, and of some other processes. I think it unnecessary to be more particular, because I cannot perceive any thing in it that had not been previously treated of by Geber.

The seventh diction treats of the preparation of blood and eggs, and the method of dividing them into their four elements. It treats also of the elixir of silver, and the elixir of gold; but it contains no chemical fact of any importance.

The eighth diction treats of the preparation of the ferment of silver, and of gold. The ninth diction treats of the whole magistery, and of the nuptials of the sun and moon; that is, of gold and silver. The tenth diction treats of weights.

The chemical writings of Avicenna are of little value, and apply chemistry rather to the supposed medical qualities of the different substances treated of, than to the advancement of the science. All the chemical knowledge which he possesses is obviously drawn from Geber. Geber, then, may be looked upon as the only chemist among the Arabians to whom we are indebted for any real improvements and new facts. It is true that the Arabian physicians improved considerably the materia medica of the Greeks, and introduced many valuable medicines into common use which were unknown before their time. It is enough to mention corrosive sublimate, manna, opium, asafœtida. It would be difficult to make out many of the vegetable substances used by the Arabian chemists; because the plants which they designated by particular names, can very seldom be identified. Botany at that time had made so little progress, that no method was known of describing plants so as to enable other persons to determine what they were.

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CHAPTER IV
OF THE PROGRESS OF CHEMISTRY UNDER PARACELSUS AND HIS DISCIPLES.

Hitherto we have witnessed only the first rude beginnings, or, as it were, the early dawn of the chemical day. It is from the time of Paracelsus that the true commencement of chemical investigations is to be dated. Not that Paracelsus or his followers understood the nature of the science, or undertook any regular or successful investigation. But Paracelsus shook the medical throne of Galen and Avicenna to its very foundation; he roused the latent energies of the human mind, which had for so long a period lain torpid; he freed medical men from those trammels, and put an end to that despotism which had existed for five centuries. He pointed out the importance of chemical medicines, and of chemical investigations, to the physician. This led many laborious men to turn their attention to the subject. Those metals which were considered as likely to afford useful medicines, mercury for example, and antimony, were exposed to the action of an infinite number of reagents, and a prodigious collection of new products obtained and introduced into medicine. Some of these were better, and some worse, than the preparations formerly employed; but all of them led to an increase of the stock of chemical knowledge, which now began to accumulate with considerable rapidity. It will be proper, therefore, to give a somewhat particular account of the life and opinions of Paracelsus, so far as they can be made out from his writings, because, though he was not himself a scientific chemist, he may be truly considered as the man through whose means the stock of chemical knowledge was accumulated, which was afterwards, by the ingenuity of Beccher, and Stahl, moulded into a scientific form.

Philippus Aureolus Theophrastus Paracelsus Bombast ab Hohenheim (as he denominates himself) was born at Einsideln, two German miles from Zurich. His father was called William Bombast von Hohenheim. He was a very near relation of George Bombast von Hohenheim, who became afterwards grand master of the order of Johannites. William Bombast von Hohenheim practised medicine at Einsideln.[143] After receiving the first rudiments of his education in his native city, he became a wandering scholastic, as was then the custom with poor scholars. He wandered from province to province, predicting the future by the position of the stars, and the lines on the hand, and exhibiting all the chemical processes which he had learned from founders and alchymists. For his initiation in alchymy, astrology, and medicine, he was indebted to his father, who was much devoted to these three sciences. Paracelsus mentions also the names of several ecclesiastics from whom he received chemical information; among others, Tritheimius, abbot of Spanheim; Bishop Scheit, of Stettbach; Bishop Erhart, of Laventall; Bishop Nicolas, of Hippon; and Bishop Matthew Schacht. He seems also to have served some years as an army surgeon, for he mentions many cures which he performed in the Low Countries, in the States of the Church, in the kingdom of Naples, and during the wars against the Venetians, the Danes, and the Dutch.

There is some uncertainty whether he received a regular college education, as was then the practice with all medical men. He acknowledges himself that his medical antagonists reproached him with never having frequented their schools; and he is perpetually affirming, that a physician should receive all his knowledge from God, and not from man. But if we can trust his own assertions, there can be no doubt that he took a regular medical degree, which implies a regular college education. He tells us, in his preface to his Chirurgia Magna, that he visited the universities of Germany, France, and Italy. He assures his readers, that he was the ornament of the schools where he studied. He even speaks of the oath which he was obliged to take when he received his medical degree; but where he studied, or where and when he received his medical degree, are questions which neither Paracelsus nor his disciples, nor his biographers, have enabled us to solve. If he ever attended a university, he must have neglected his studies, otherwise he could not have been ignorant, as he confessedly was, of the very first elements of the most common kinds of knowledge. But if he neglected the universities, he laboured long and assiduously with the rich Sigismond Fuggerus, of Schwartz, in order to learn the true secret of forming the philosopher’s stone.

He gives us some details of the numerous journeys that he made, as was customary with the alchymists of the time, into the mountains of Bohemia, the East, and Sweden, to inspect the mines, to get himself initiated into the mysteries of the eastern adepts, to inspect the wonders of nature, and to view the celebrated diamond mountain, the position of which, however, he unfortunately forgets to specify.

In the preface to his Chirurgia Magna, he informs us that he traversed Spain, Portugal, England, Prussia, Poland, and Transylvania; where he not only profited by the information of the medical men with whom he became acquainted, but that he drew much precious information from old women, gipsies, conjurors, and chemists.[144] He spent several years in Hungary; and informs us that at Weissenburg, in Croatia, and in Stockholm, he was taught by several old women to prepare drinks capable of curing ulcers. He is said also to have made a voyage into Egypt, and even into Tartary; and he accompanied the son of the Kan of the Tartars to Constantinople, in order to learn the secret of the philosopher’s stone from Trismogin, who inhabited that capital. This prodigious activity, this constant motion from place to place, left him but little leisure for reading: accordingly he informs us himself, that during the space of ten years he never opened a book, and that his whole library consisted only of six sheets. The inventory of his books, drawn up after his death, confirms this recital; for they consisted only of the Bible, the Concordance to the Bible, the New Testament, and the Commentaries of St. Jerome on the Evangelists.

We know not at what period he returned back to Germany; but at the age of thirty-three the great number of fortunate cures which he had performed rendered him an object of admiration to the people, and of jealousy to the rival physicians of the time. He assures us that he cured eighteen princes whose diseases had been aggravated by the practitioners devoted to the system of Galen. Among others he cured Philip, Margrave of Baden, of a dysentery, who promised him a great reward, but did not keep his promise, and even treated him in a way unworthy of that prince. This cure, however, and others of a similar nature, added greatly to his celebrity; and in order to raise his reputation to the highest possible pitch, he announced publicly that he was able to cure all the diseases hitherto reckoned incurable; and that he had discovered an elixir, by means of which the life of man might be prolonged at pleasure to any extent whatever. He began the practice, which has since been so successfully followed in this country, of dispensing medicines gratuitously to the poor, in order to induce the rich to apply to him for assistance when they were overtaken with diseases.

In the year 1526 Paracelsus was appointed professor of physic and surgery in the University of Basil. This appointment was given him, it is said, by the recommendation of Œcolampadius. He introduced the custom of lecturing in the common language of the country, as is at present the universal practice: but during the time of Paracelsus, and long after indeed, all lectures were delivered in Latin. The new method which he followed in explaining the theory and practice of the art; the numerous fortunate cures which he stated in confirmation of his method of treatment; the emphasis with which he spoke of his secrets for prolonging life, and for curing every kind of disease without distinction, but still more his lecturing in a language which was understood by the whole population, drew to Bâle an immense crowd of idle, enthusiastic, and credulous hearers.

The lectures which he delivered on Practical Medicine still remain, written in a confused mixture of German and barbarous Latin, and containing little or nothing except a farrago of empirical remedies, advanced with the greatest confidence. They have a much greater resemblance to a collection of quack advertisements than to the sober lectures of a professor in a university. In the month of November, 1526, he wrote to Christopher Clauser, a physician in Zurich, that as Hippocrates was the first physician among the Greeks, Avicenna among the Arabians, Galen among the Pergamenians, and Marsilius among the Italians, so he was beyond dispute the greatest physician among the Germans. Every country produces an illustrious physician, whose medicines are adapted to the climate in which he lived, but not suited to other countries. The remedies of Hippocrates were good to the Greeks, but not suitable to the Germans; thus it was necessary that an inspired physician should spring up in every country, and that he was the person destined to teach the Germans the art of curing all diseases.[145]

Paracelsus began his professorial career by burning publicly, in his class-room, and in the presence of his pupils, the works of Galen and Avicenna, assuring his hearers that the strings of his shoes possessed more knowledge than those two celebrated physicians. All the universities united had not, he assured them, as much knowledge as was contained in his own beard, and the hairs upon his neck were better informed than all the writers that ever existed put together. To give the reader an idea of the arrogant absurdity of his pretensions, I shall translate a few sentences of the preface to his tract, entitled “Paragranum,” where he indulges in his usual strain of rodomontade: “Me, me you shall follow, you Avicenna, you Galen, you Rhazes, you Montagnana, you Mesue. I shall not follow you, but you shall follow me. You, I say, you inhabitants of Paris, you inhabitants of Montpelier, you Suevi, you Misnians, you inhabitants of Cologne, you inhabitants of Vienna; all you whom the Rhine and the Danube nourish, you who inhabit the islands of the sea; you also Italy, you Dalmatia, you Athens, you Greek, you Arabian, you Israelite—I shall not follow you, but you shall follow me. Nor shall any one lurk in the darkest and most remote corner whom the dogs shall not piss upon. I shall be the monarch, the monarchy shall be mine. If I administer, and I bind up your loins, is he with whom you are at present delighted a Cacophrastus? This ordure must be eaten by you.”

“What will your opinion be when you see your Cacophrastus constituted the chief of the monarchy? What will you think when you see the sect of Theophrastus leading on a solemn triumph, if I make you pass under the yoke of my philosophy? your Pliny will you call Cacopliny, and your Aristotle, Cacoaristotle? If I plunge them together with your Porphyry, Albertus, &c., and the whole of their compatriots into my necessary.” But the terms become now so coarse and indelicate, that I cannot bring myself to proceed further with the translation. Enough has been given to show the extreme arrogance and folly of Paracelsus.

So far, however, was this impudence and grossness from injuring the interest of Paracelsus, that we are assured by Ramus and Urstisius that it contributed still further to increase it. The coarseness of his language was well suited to the vulgarity of the age; and his arrogance and boasting were considered, as usual, as a proof of superior merit. The cure which he performed on Frobenius, drew the attention of Erasmus himself, who consulted him about the diseases with which he was afflicted; and the letters that passed between them are still preserved. The epistle of Paracelsus is short, enigmatical, and unintelligible; that of Erasmus is distinguished by that clearness and elegance which characterize his writings.[146] But Frobenius died in the month of October, 1527, and the antagonists of Paracelsus attributed his death (and probably with justice) to the violent remedies which had been administered to a man whose constitution had been destroyed by the gout.

His death contributed not a little to tarnish the glory of Paracelsus: but he suffered the greatest injury from the habits of intoxication in which he indulged, and from the vulgarity of the way in which he spent his time. He hardly ever went into his class-room to deliver a lecture till he was half intoxicated, and scarcely ever dictated to his secretaries till he had lost the use of his reason by a too liberal indulgence in wine. If he was summoned to visit a patient, he scarcely ever went but in a state of intoxication. Not unfrequently he passed the whole night in the alehouse, in the company of peasants, and when morning came, was quite incapable of performing the duties of his station. On one occasion, after a debauch, which lasted the whole night, he was called next morning to visit a patient; on entering the room, he inquired if the sick person had taken any thing: “Nothing,” was the answer, “except the body of our Lord.” “Since you have already,” says he, “provided yourself with another physician, my presence here is unnecessary,” and he left the apartment instantly. When Albertus Basa, physician to the king of Poland, visited Paracelsus in the city of Basel, he carried him to see a patient whose strength was completely exhausted, and which, in his opinion, it was impossible to restore; but Paracelsus, wishing to make a parade of his skill, administered to him three drops of his laudanum, and invited him to dine with him next day.[147] The invitation was accepted, and the sick man dined next day with his physician.

Towards the end of the year 1527 a disgraceful dispute into which he entered brought his career, as a professor, to a sudden termination. The canon Cornelius, of Lichtenfels, who had been long a martyr to the gout, employed him as his physician, and promised him one hundred florins if he could cure him. Paracelsus made him take three pills of laudanum, and having thus freed him from pain, demanded the sum agreed upon; but Lichtenfels refused to pay him the whole of it. Paracelsus summoned him before the court, and the magistrate of Basle decided that the canon was bound to pay only the regular price of the medicine administered. Irritated at this decision, our intoxicated professor uttered a most violent invective against the magistrate, who threatened to punish him for his outrageous conduct. His friends advised him to save himself by flight. He took their advice, and thus abdicated his professorship. But, by this time, his celebrity as a teacher had been so completely destroyed by his foolish and immoral conduct, that he had lost all his hearers. In consequence of this state of things, his flight from Basle produced no sensation whatever in that university.

Paracelsus betook himself, in the first place, to Alsace, and sent for his faithful follower, the bookseller, Operinus, together with the whole of his chemical apparatus. In 1528 we find him at Colmar, where he recommenced his ambulating life of a theosophist, which he had led during his youth. His book upon syphilis, known at that time by the name of Morbus Gallicus, was dedicated at Colmar, to the chief magistrate of Colmar, Hieronymus Bonerus.[148] In 1531 he was at Saint-Gallen; in 1535, at Pfeffersbade, and in 1536, at Augsburg, where he dedicated his Chirurgia Magna to Malhausen. At the request of John de Leippa, Marshal of Bohemia, he undertook a journey into Moravia; as that nobleman, having been informed that Paracelsus understood the method of curing the gout radically, was anxious to put himself under his care. Paracelsus lived for a long time at Kroman, and its environs. John de Leippa, instead of receiving any benefit from the medicines administered to him, became daily worse, and at last died. This was the fate also of the lady of Zerotin, in whom the remedies of Paracelsus produced no fewer than twenty-four epileptic fits in one day. Paracelsus, instead of waiting the disgrace with which the death of this lady would have overwhelmed him, announced his intention of going to Vienna, that he might see how they would treat him in that capital.

It is said, that from Vienna he went into Hungary; but in 1538, we find him in Villach, where he dedicated his Chronica et Origo Carinthiæ to the states of Carinthia.[149] His book, De Natura Rerum, had been dedicated to Winkelstein, and the dedication is dated also at Villach, in the year 1537.[150] In 1540 he was at Mindelheim, and in 1541, at Strasburg, where he died, in St. Stephen’s hospital, in the forty-eighth year of his age.

To form an accurate idea of this most extraordinary man, we must attend to his habits, and to the situation in which he was placed. He had acquired such a habit of moving about, that he assures us himself he found it impossible for him to continue for any length of time in one place. He was always surrounded by a number of followers, whom neither his habits of intoxication, nor the foolish and immoral conduct in which he was accustomed to indulge, could induce to forsake him. The most celebrated of these was Operinus, a printer at Basle, on whom Paracelsus lavishes the most excessive praises, in his book De Morbo Gallico. But Operinus loaded his master with obloquy, being provoked at him because he had not made him acquainted with the secret of the philosopher’s stone, as he had promised to do. We must therefore be cautious in believing the stories that he relates to the discredit of his master. We know the names of two others of his followers; Francis, who assures us that Paracelsus was devoted to the transmutation of metals; and George Vetter, who considered him as a magician; as was the opinion also of Operinus. Paracelsus himself, speaks of Dr. Cornelius, whom he calls his secretary, and in honour of whom he wrote several of his libels. Other libels are dedicated to Doctors Peter, Andrew, and Ursinus, to the licentiate Pancrace, and to Mr. Raphael. On this occasion he complains bitterly of the infidelity of his servants, who, he says, had succeeded in stealing from him several of his secrets; and had by this means been enabled to establish their reputation. He accuses equally the barbers and bathers that followed him, and is no less severe upon the physicians of every country through which he travelled.

When we attempt to form an accurate conception of the medical and philosophical opinions of this singular man, we find ourselves beset with almost insurmountable difficulties. His statements are so much at variance with each other, in his different pieces, and so much confusion reigns with respect to the order of publication, that we know not what to fix on as his last and maturest opinions. His style is execrable; filled with new words of his own coining, and of mysticisms either introduced to excite the admiration of the ignorant, or from the fanaticism and credulity of the writer, who was undoubtedly, to a considerable extent, the dupe of his own impostures. That he was in possession of the philosopher’s stone, or of a medicine capable of prolonging life to an indefinite length, as he all along asserted, he could not himself believe; but he had boasted so long and so loudly of his wonderful cures, and of the efficacy of his medicines, that there can be no doubt that he ultimately placed implicit faith in them. The blunders of the transcribers whom he employed to copy his works, may perhaps account for some of the contradictions which they contain. But how can we look for a regular system of opinions from a man who generally dictated his works when in a state of intoxication, and thus laboured under an almost constant deprivation of reason.

His obscurity was partly the effect of design, and no doubt was intended to exalt the notions entertained of his profundity. He uses common words in new significations, without giving any indication of the change which he introduced. Thus anatomy, in the writings of Paracelsus, signifies not the dissection of dead animals to determine their structure, but it means the nature, force, and magical designation of a thing. And as, according to the Platonic and Cabalistic theory, every earthly body is formed after the model of a heavenly body, Paracelsus calls anatomy the knowledge of that model, of that ideal, or of that paradigm after which all things are created. He terms the fundamental force of a thing a star, and defines alchymy the art of drawing out the stars of metals. The star is the source of all knowledge. When we eat, we introduce into our bodies the star, which is then modified, and favours nutrition.

It is probable that many of his obscure and unintelligible expressions are the fruit of ignorance. Thus he uses the term pagoyus, instead of paganus. He gives the name of pagoyæ to the four entities, or causes of diseases, founded on the influence of the stars, to the elementary qualities; to the occult qualities, and to the influence of spirits; because these had been already admitted by the Pagans. But the fifth entity, or cause of disease, which has God immediately for its author, is non pagoya. The undimia of Paracelsus is our œdema; only he applies the name to every kind of dropsy. The Latin word tonitru, we find is declined by Paracelsus. Thus he says, lapis tonitrui. The well-known line of Ovid, Tollere nodosam nescit medicina podagram,
He travestied into Nescit tartaream Roades curare podagram.[151]
Roades, he says, means medicines for horses; and if any person wishes a more elegant verse, he may make it for himself.[152] He employs, also, a great number of words to which no meaning whatever can be attached; and to which, in all probability, he himself had affixed none.

As is the case with all fanatics, he treated with contempt every kind of knowledge acquired by labour and application; and boasted that his wisdom was communicated to him directly by God Almighty. The theosophist who is worthy of partaking of the divine light, has no occasion for adopting a positive religion, nor of subjecting himself to any kind of religious ceremony. The divine light within, which assimilates him to the Deity, more than compensates for all these vulgar usages, and raises the illuminated votary far above the beggarly elements of external worship. Accordingly, Paracelsus has been accused of treating the public worship of the Deity with contempt. Not satisfied with the plain sense of the book, he attempted to explain in a mystical manner the words and syllables of the Bible. He accused Luther of not going far enough. “Luther,” says he, “is not worthy of untying the strings of my shoes: should I undertake a reformation, I would begin by sending the pope and the reformers themselves to school.” God, says Paracelsus, is the first and most excellent of writers. The Holy Scripture conducts us to all truth, and teaches us all things. But medicine, philosophy, and astronomy, are among the number of things. Therefore, when we want to know what magical medicine is, we must consult the Apocalypse. The Bible, with its paraphrases, is the key to the theory of diseases. It puts it in our power to understand St. John, who, like Daniel, Ezekiel, Moses, &c., was a magician, a cabalist, a diviner. The first duty of a physician is to study the Cabala, without which he must every moment commit a thousand blunders. “Learn,” says he, “the cabalistic art, which includes under it all the others.” “Man invents nothing, the devil invents nothing; it is God alone who unveils to us the light of nature.” “God honoured at first with his illumination the blind pagans, Apollo, Æsculapius, Machaon, Podalirius, and Hippocrates, and imparted to them the genius of medicine; their successors were the sophists.” One would suppose, from this passage, that Paracelsus had read and studied Hippocrates, and that he held him in high estimation. But the commentaries which he has left on some of the aphorisms, show evidently that he did not even understand the Greek physician. “The compassion of God,” says he, “is the only foundation of medical science, and not a knowledge of the great masters, or of the writings which they have left in Greek and Latin.” “God often acts in dreams by the light of nature, and points out to man the manner of curing diseases.” “This knowledge renders all those objects visible which would otherwise escape the sight; and when faith is joined with it, nothing is then impossible to the theosophist, who may transport the ocean to the top of Mount Ætna, and Olympus into the Red Sea.” Paracelsus predicts that by the year 1590 Christian theosophy would be generally spread over the world, and that the Galenical schools would be almost or entirely overthrown.

We find in Paracelsus some traces of the opinions of the Gnostics and Arians, who considered Christ as the first emanation of the Deity. He calls the first man parens hominis; and makes all spirits emanate from him. He is the limbus minor, or the last creature, into whom enters the great limbus, or the seed of all the creatures, the infinite being. All the sciences, and all the arts of man, are derived from this great limbus; and he who can sink himself in the little limbus, that is to say, in Adam, and who can communicate by faith with Jesus Christ, may invoke all spirits. Those who owe their science to this limbus, are the best informed; those who derive it from the stars, occupy the last rank; and those who owe it to the light of nature, are intermediate between the preceding. Jesus Christ, in his capacity of limbus minor and first man, being always an emanation of the Divinity; and, consequently, a subordinate personage. These ideas explain to us why Paracelsus passed for an Arian, and was supposed not to believe in the Divinity of Jesus Christ. He was of opinion that the faithful performed miracles, and operated magical cures by their simple confidence in God the Father, and not by their faith in Christ; but he adds, however, that we ought to pray to Jesus, in order to obtain his intercession.

From the preceding attempt to explain the opinions of Paracelsus, it will be evident to the reader that he was both a fanatic and impostor, and that his theory (if such a name can be given to the reveries of a drunkard), consisted in uniting medicine with the doctrines of the Cabala. A few more observations will be necessary to develop his dogmas still further.

Every body, in his opinion, and man in particular, is double, consisting of a material and spiritual substance.[153] The spiritual, which may be called the sideric, results from the celestial influences; and we may trace after it a figure capable of producing all kinds of magical effects. When we can act upon the body itself, we act at the same time upon the spiritual form by characters and conjurations.[154] Yet, in another passage, he blames all magical ceremonies, and ascribes them to want of faith. The celestial intelligences impress upon material bodies certain signs, which manifest their influence. The perfection of art consists in understanding the meaning of these signs, and in determining from them the nature, qualities, and essence of a body. Adam, the first man, had a perfect knowledge of the Cabala; he could interpret the signatures of all things. It was this which enabled him to assign to the animals names which suited them best. A man who renounces all sensuality, and is blindly obedient to the will of God, is capable of taking a share in the actions which celestial intelligences perform; and consequently is possessed of the philosopher’s stone. Never does he want any thing; all creatures in earth and in heaven are obedient to him; he can cure all diseases, and prolong his life as long as he pleases; because he possesses the tincture which Adam and the patriarch’s before the flood employed to prolong the term of their existence.[155] Beelzebub, the chief of the demons, is also subject to the power of magic: and who can blame the theosophist for believing in the devil? He ought, however, to take care to prevent this malignant spirit from commanding him. Paracelsus was often wont to say, “If God does not aid me, the devil will help me.”

Pantheism was one of the principal dogmas of the Cabala; and Paracelsus adopts it in all its grossness. He affirms perpetually that every thing is animated in the universe; that every thing which exists, eats, drinks, and voids excrements: even minerals and liquids take food and void the digested remains of their nourishment.[156] This opinion leads necessarily to the admission of a great number of spiritual substances, intermediate between material and immaterial in every part of the sublunary world, in water, air, earth, and fire; who, as well as man, eat, drink, converse, beget children; but which approach pure spirits in this, that they are more transparent, and infinitely more agile than all other animal bodies. Man possesses a soul, of which these pure spirits are destitute. Hence it happens that these spiritual substances are at once body and spirit without a soul. When they die (for like the human race they are subject to death), no soul remains. Like us they are exposed to diseases. Their names vary according to the places that they occupy. When they inhabit the air, they are called sylphs; when the water, nymphs; when the earth, pigmies; when the fire, salamanders.[157] The inhabitants of the waters are also called undinæ, and those of the fire vulcani. The sylphs approach nearest to our nature, as they live in the air like us. The sylphs, nymphs, and pigmies, sometimes obtain permission from God to make themselves visible, to converse with men, to indulge in carnal pleasures, and to produce children. But the salamanders have no relation to man. These spiritual beings are acquainted with the future, and capable of revealing it to man. They appear under the form of ignes fatui. We have also the history of the fairies and the giants; and are told how these spiritual beings are the guardians of concealed treasures; and how these sylphs, nymphs, pigmies, and salamanders, may be charmed, and their treasures taken from them.

This division of man into body and spirit, and of the things of nature into visible and invisible, has in all ages of the world, been adopted by fanatics, because it enabled them to explain the history of ghosts, and a thousand similar prejudices. Hence the distinction between soul and spirit, which is so very ancient; and hence the three following harmonies to which the successors of Paracelsus paid a particular attention: Soul, Spirit, Body, Mercury, Sulphur, Salt, Water, Air, Earth. The will and the imagination of man acts principally by means of the spirit. Hence the reason of the efficacy of sorcery and magic. The nævi materni are the impressions of these vice-men, and Paracelsus calls them cocomica signa. The sideric body of man draws to him, by imagination, all that surrounds him, and particularly the stars, on which it acts like a magnet. In this manner, women with child, and during the regular period of monthly evacuation, having a diseased imagination, are not only capable of poisoning a mirror by their breath, but of injuring the infants in their wombs, and even also of poisoning the moon. But it seems needless to continue this disagreeable detail of the absurd and ridiculous opinions which Paracelsus has consigned to us in his different tracts.

The Physiology of Paracelsus (if such a name can be applied to his reveries) is nothing else than an application of the laws of the Cabala to the explanation of the functions of the body. There exists, he assures us, an intimate connexion between the sun and the heart, the moon and the brain, Jupiter and the liver, Saturn and the spleen, Mercury and the lungs, Mars and the bile, Venus and the kidneys. In another part of his works, he informs us that the sun acts on the umbilicus and the middle parts of the abdomen, the moon on the spine, Mercury on the bowels, Venus on the organs of generation, Mars on the face, Jupiter on the head, and Saturn on the extremities. The pulse is nothing else than the measure of the temperature of the body, according to the space of the six places which are in relation to the planets. Two pulses under the sole of the feet belong to Saturn and Jupiter, two at the elbow to Mars and Venus, two in the temples to the moon and mercury. The pulse of the sun is found under the heart. The macrocosm has also seven pulses, which are the revolutions of the seven planets, and the irregularity or intermittence of these pulses, is represented by the eclipses. The moon and Saturn are charged in the macrocosm with thickening the water, which causes it to congeal. In like manner the moon of the microcosm, that is to say the brain, coagulates the blood. Hence melancholy persons, whom Paracelsus calls lunatics, have a thick blood. We ought not to say of a man that he has such and such a complexion; but that it is Mars, Venus, &c., so that a physician ought to know the planets of the microcosm, the arctic and antarctic pole, the meridian, the zodiac, the east and the west, before trying to explain the functions or cure the diseases.[158] This knowledge is acquired by a continual comparison of the macrocosm with the microcosm. What must have been the state of medicine at the time when Paracelsus wrote, when the propagator of such opinions could be reckoned one of the greatest of its reformers?

The system of Galen had for its principal basis the doctrine of the four elements, fire, air, water, and earth. Paracelsus neglected these elements, and multiplied the substances of the disease itself. He admits, strictly speaking, three or four elements; namely, the star, the root, the element, the sperm, which he distinguishes by the name of the true seed. All these elements were originally confounded together in the chaos or yliados. The star is the active force which gives form to matter. The stars are reasonable beings addicted to sodomy and adultery, like other creatures. Each of them draws at pleasure out of the chaos, the plant and the metal to which it has an affinity, and gives a sideric form to their root. There are two kinds of seed; the sperm is the vehicle of the true seed. It is engendered by speculation, by imagination, by the power of the star. The occult, invisible, sideric body produces the true seed, and the Adamic man secretes only the visible envelope of it. Putrefaction cannot give birth to a new body: the seed must pre-exist, and it is developed during putrefaction by the power of the stars. The generation of animals is produced by the concourse of the infinite number of seeds which detach themselves from all parts of the body. Thus the seed of the nose reproduces a nose, that of the eye the eye, and so on.

With respect to the elements themselves, Paracelsus admits occasionally their influence on the functions of the body, and the theory of diseases; but he deduces the faculties which they possess from the stars. It was he that first shook the doctrine of the four elements, originally contrived by Empedocles. Alchymy had introduced another set of elements, and the alchymists maintained that salt, sulphur, and mercury, were the true elements of things. Paracelsus endeavoured to reconcile these chemical elements with his cabalistic ideas, and to show more clearly their utility in the theory of medicine. He invented a sideric salt, which can only be perceived by the exquisite senses of a theosophist, elevated by the abnegation of all gross sensuality to a level with pure and spiritual demons. This salt is the cause of the consistence of bodies, and it is it which gives them the faculty of being reproduced from their ashes.

Paracelsus imagined also a sideric sulphur, which being vivified by the influence of the stars, gives bodies the property of growing, and of being combustible. He admits also a sideric mercury, the foundation of fluidity and volatilization. The concourse of these three substances forms the body. In different parts of his works, Paracelsus says, that the elements are composed of these three principles. In plants he calls the salt balsam, the sulphur resin and the mercury gotaronium. In other passages he opposes the assertion of the Galenists, that fire is dry and hot, air cold and moist, earth dry and cold, water moist and cold. Each of these elements, he says, is capable of admitting all qualities, so that in reality there exists a dry water, a cold fire, &c.

I must not omit another remarkable physiological doctrine of Paracelsus, namely, that there exists in the stomach a demon called Archæus, who presides over the chemical operations which take place in it, separating the poisonous from the nutritive part of food, and furnishing the alimentary substances with the tincture, in consequence of which they become capable of being assimilated. This ruler of the stomach, who changes bread into blood, is the type of the physician, who ought to keep up a good understanding with him, and lend him his assistance. To produce a change in the humours ought never to be the object of the true physician, he should endeavour to concentrate all his operations on the stomach and the ruler who reigns in it. This Archæus to whom the name of Nature may also be given, produces all the changes by his own power. It is he alone who cures diseases. He has a head and hands, and is nothing else than the spirit of life, the sideric body of man, and no other spirit besides exists in the body. Each part of the body has also a peculiar stomach in which the secretions are elaborated.

There are, he informs us, five different causes of diseases. The first is the ens astrorum. The constellations do not immediately induce diseases, but they alter and infect the air. This is what, properly speaking constitutes the entity of the stars. Some constellations sulphurize the atmosphere, others communicate to it arsenical, saline, or mercurial qualities. The arsenical astral entities injure the blood, the mercurial the head, the saline the bones and the vessels. Orpiment occasions tumours and dropsies, and the bitter stars induce fever.

The second morbific cause is the ens veneni, which proceeds from alimentary substances: when the archeus is languid putrefaction ensues, either localiter or emuncturaliter. This last takes place when those evacuations, which ought to be expelled by the nose, the intestines, or the bladder, are retained in the body. Dissolved mercury escapes through the pores of the skin, white sulphur by the nose, arsenic by the ears, sulphur diluted with water by the eyes, salt in solution by the urine, and sulphur deliquesced by the intestines.

The third morbific cause of disease is the ens naturale; but Paracelsus subjects to the ens astrorum the principles which the schools are in the habit of arranging among the number of natural causes. The ens spirituale forms the fourth species and the ens deale or Christian entity the fifth. This last class comprehends all the immediate effects of divine predestination.

It would lead us too far if I were to point out the strange methods which he takes to discover the cause of diseases. But his doctrine concerning tartar is too important, and does our fanatic too much credit to be omitted. It is without doubt the most useful of all the innovations which he introduced. Tartar according to him, is the principle of all the maladies proceeding from the thickening of the humours, the rigidity of the solids, or the accumulation of earthy matter. Paracelsus thought the term stone not suitable to indicate that matter, because it applies only to one species of it. Frequently the principle proceeds from mucilage, and mucilage is tartar. He calls this principle tartar (tartarus) because it burns like hellfire, and occasions the most dreadful diseases. As tartar (bitartrate of potash) is deposited at the bottom of the wine-cask, in the same way tartar in the living body is deposited on the surface of the teeth. It is deposited on the internal parts of the body when the archæus acts with too great impetuosity and in an irregular manner, and when it separates the nutritive principle with too much impetuosity. Then the saline spirit unites itself to it and coagulates the earthy principle, which is always present, but often in the state of materia prima without being coagulated.

In this manner tartar, in the state of materia prima, may be transmitted from father to son. But it is not hereditary and transmittable when it has already assumed the form of gout, of renal calculus, or of obstruction. The saline spirit which gives it its form, and causes its coagulation, is seldom pure and free from mixture; usually it contains alum, vitriol, or common salt; and this mixture contributes also to modify the tartarous diseases. The tartar may be likewise distinguished according as it comes from the blood itself, or from foreign matters accumulated in the humours. The great number of calculi which have been found in every part of the body, and the obstructions, confirm the generality of this morbific cause, to which are due most of the diseases of the liver. When the tartarous matter is increased by certain articles of food, renal calculi are engendered, a calculous paroxysm is induced, and violent pain is occasioned. It acts as an emetic, and may even give occasion to death, when the saline spirit becomes corrosive; and when the tartar coagulated by it becomes too irritating.

Tartar, then, is always an excrementitious substance, which in many cases results from the too great activity of the digestive forces. It may make its appearance in all parts of the body, from the irregularity and the activity, too energetic or too indolent, of the archeus; and then it occasions particular accidents relative to each of the functions. Paracelsus enumerates a great number of diseases of the organs, which may be explained by that one cause; and affirms, that the profession of medicine would be infinitely more useful, if medical men would endeavour to discover the tartar before they tried to explain the affections.

Paracelsus points out, also, the means by which we can distinguish the presence of tartar in urine. For this it is necessary, not merely to inspect the urine, but to subject it to a chemical analysis. He declaims violently against the ordinary ouroscopy. He divides urine into internal and external; the internal comes from the blood, and the external announces the nature of the food and drink which has been employed. To the sediment of urine he gives the new name of alcola, and admits three species of it, namely, hypostasis, divulsio, and sedimen. The first is connected with the stomach, the second with the liver, and the third with the kidneys; and tartar predominates in all the three.

The Cabala constantly directs Paracelsus in his therapeutics and materia medica. As all terrestrial things have their image in the region of the stars, and as diseases depend also on the influence of the stars, we have nothing more to do, in order to obtain a certain cure for these diseases, than to discover, by means of the Cabala, the harmony of the constellations. Gold is a specific against all diseases of the heart, because, in the mystic scale, it is in harmony with that viscus. The liquor of the moon and crystal cure the diseases of the brain. The liquor alkahest and cheiri are efficacious against those of the liver. When we employ vegetable substances, we must consider their harmony with the constellations, and their magical harmony with the parts of the body and the diseases, each star drawing, by a sort of magical virtue, the plant for which it has an affinity, and imparting to it its activity. So that plants are a kind of sublunary stars. To discover the virtues of plants, we must study their anatomy and cheiromancy; for the leaves are their hands, and the lines observable on them enable us to appreciate the virtues which they possess. Thus the anatomy of the chelidonium shows us that it is a remedy for jaundice. These are the celebrated signatures by means of which we deduce the virtues of vegetables, and the medicines of analogy which they present in relation to their form. Medicines, like women, are known by the forms which they affect. He who calls in question this principle, accuses the Divinity of falsehood, the infinite wisdom of whom has contrived these external characters to bring the study of them more upon a level with the weakness of the human understanding. On the corolla of the euphrasia there is a black dot; from this we may conclude that it furnishes an excellent remedy against all diseases of the eye. The lizard has the colour of malignant ulcers, and of the carbuncle; this points out the efficacy which that animal possesses as a remedy.

These signatures were exceedingly convenient for the fanatics, since they saved them the trouble of studying the medical virtues of plants, but enabled them to decide the subject à priori. Paracelsus acted very considerately, when he ascribed these virtues principally to the stars, and affirmed that the observation of favourable constellations is an indispensable condition in the employment of these medicines. “The remedies are subjected to the will of the stars, and directed by them; you ought therefore to wait till heaven is favourable, before ordering a medicine.”

Paracelsus considered all the effects of plants as specifics, and the use of them as secrets. The same notions explain the eulogy which he bestowed on the elixir of long life, and upon all the means which he employed to prolong the term of existence. He believed that these methods, which contained the materia prima, served to repair the constant waste of that matter in the human body. He was acquainted, he says, with four of these arcana, to which he applied the mystic terms, mercury of life, philosopher’s stone, &c. The polygonum persicaria was an infallible specific against all the effects of magic. The method of using it is, to apply it to the suffering part, and then to bury it in the earth. It draws out the malignant spirits like a magnet, and it is buried to prevent these malignant spirits from making their escape.

The reformation of Paracelsus had the great advantage of representing chemistry as an indispensable art in the preparation of medicines. The disgusting decoctions and useless syrups gave place to tinctures, essences, and extracts. Paracelsus says, expressly, that the true use of chemistry is to prepare medicines, and not to make gold. He takes that opportunity of declaiming against cooks and innkeepers, who drown medicines in soup, and thus destroy all their properties. He blames medical men for prescribing simples, or mixtures of simples, and affirms that the object should always be to extract the quintessence of each substance; and he describes at length the method of extracting this quintessence. But he was very little scrupulous about the substances from which this quintessence was to be extracted. The heart of a hare, the bones of a hare, the bone of the heart of a stag, mother-of-pearl, coral, and various other bodies may, he says, be used indiscriminately to furnish a quintessence capable of curing some of the most grievous diseases.

Paracelsus combats with peculiar energy the method of cure employed by the disciples of Galen, directed solely against the predominating humours, and the elementary qualities. He blames them for attempting to correct the action of their medicines, by the addition of useless ingredients. Fire and chemistry, he affirmed, are the sole correctives. It was Paracelsus that first introduced tin as a remedy for worms, though his mode of employing it was not good.

I have been thus particular in pointing out the philosophical and medical opinions of Paracelsus, because they were productive of such important consequences, by setting medical men free from the slavish deference which they had been accustomed to pay to the dogmas of Galen and Avicenna. But it was the high rank to which he raised chemistry, by making a knowledge of it indispensable to all medical men; and by insisting that the great importance of chemistry did not consist in the formation of gold, but in the preparation of medicines, that rendered the era of Paracelsus so important in the history of chemistry; for after his time the art of chemistry was cultivated by medical men in general—it became a necessary part of their education, and began to be taught in colleges and medical schools. The object of chemistry came to be, not to discover the philosopher’s stone, but to prepare medicines; and a great number of new medicines, both from the mineral and vegetable kingdom—some of more, some of less, consequence, soon issued from the laboratories of the chemical physicians.

There can be little doubt that many chemical preparations were either first introduced into medicine by Paracelsus, or at least were first openly prescribed by him: though from the nature of his writings, and the secrecy in which he endeavoured to keep his most valuable remedies, it is not easy to point out what these remedies were. Mercury is said to have been employed in medicine by Basil Valentine; but it was Paracelsus who first used it openly as a cure for the venereal disease, and who drew general attention to it by his encomiums on its medical virtues, and by the eclat of the cures which he performed by means of it, after all the Galenical prescriptions of the schools had been tried in vain.

He ascertained that alum contains, united to an acid, not a metallic oxide, but an earth. He mentions metallic arsenic; but there is some reason for believing that this metal was known to Geber and the Arabian physicians. Zinc is mentioned by him, and likewise bismuth, as substances not truly metallic, but approaching to metals in their properties: for malleability and ductility were considered by him as essential to the metals.[159] I cannot be sure of any other chemical fact which appears in Paracelsus, and which was not known before his time. The use of sal ammoniac in subliming several metallic calces, was familiar to him, but it had long ago been explained by Geber. It is clear also that Geber was acquainted with aqua regia, and that he employed it to dissolve gold. Paracelsus’s reputation as a chemist, therefore, depends not upon any discoveries which he actually made, but upon the great importance which he attached to the knowledge of it, and to his making an acquaintance with chemistry an indispensable requisite of a medical education.

Paracelsus, as the founder of a new system of medicine, the object of which was to draw chemistry out of that state of obscurity and degradation into which it had been plunged, and to give it the charge of the preparation of medicine, and presiding over the whole healing art, deserved a particular notice; and I have even endeavoured, at some length, to lay his system of opinions, absurd as it is, before the reader. But the same attention is not due to the herd of followers who adopted his absurdities, and even carried them, if possible, still further than their master: at the same time there are one or two particulars connected with the Paracelsian sect which it would be improper to omit.

The most celebrated of his followers was Leonhard Thurneysser-zum-Thurn, who was born in 1530, at Basle, where his father was a goldsmith. His life, like that of his master, was checkered with very extraordinary vicissitudes. In 1560 he was sent to Scotland to examine the lead-mines in that country. In 1558 he commenced miner and sulphur extractor at Tarenz on the Inn, and was so successful, that he acquired a great reputation. He had turned his attention to medicine on the Paracelsian plan, and in 1568 made himself distinguished by several important cures which he performed. In 1570 he published his Quinta Essentia, with wooden cuts, in Munster; from thence he went to Frankfort on the Oder, and published his Piso, a work which treats of waters, rivers, and springs. John George, Elector of Brandenburg, was at that time in Frankfort, and was informed that the treatise of Thurneysser pointed out the existence of a great deal of riches in the March of Brandenburg, till that time unknown. His courtiers, who were anxious to establish mines in their possessions, united in recommending the author. He was consulted about a disease under which the wife of the elector was labouring, and having performed a cure, he was immediately named physician to this prince.

He turned this situation to the best account. He sold Spanish white, and other cosmetics, to the ladies of the court; and instead of the disgusting decoctions of the Galenists, he administered the remedies of Paracelsus under the pompous titles of tincture of gold, magistery of the sun, potable gold, &c. By these methods he succeeded in amassing a prodigious fortune, but was not fortunate enough to be able to keep it. Gaspard Hoffmann, professor at Frankfort, a well-informed and enlightened man, published a treatise, the object of which was to expose the extravagant pretensions and ridiculous ignorance of Thurneysser. This book drew the attention of the courtiers, and opened the eyes of the elector. Thurneysser lost much of his reputation; and the methods by which he attempted to bolster himself up, served only to sink him still lower in the estimation of men of sense. Among other things, he gave out that he was the possessor of a devil, which he carried about with him in a bottle. This pretended devil was nothing else than a scorpion, preserved in a phial of oil. The trick was discovered, and the usual consequences followed. He lost a process with his wife, from whom he was separated; this deprived him of the greatest part of his fortune. In 1584 he fled to Italy, where he occupied himself with the transmutation of metals, and he died at Cologne in 1595.

Thurneysser extols Paracelsus as the only true physician that ever existed. His Quintessence is written in verse. In the first book The Secret is the speaker. He is represented with a padlock in his mouth, a key in his hand, and seated on a coffer in a chamber, the windows of which are shut. This personage teaches that all things are composed of salt, sulphur, and mercury, or of earth, air, and water; and consequently that fire is excluded from the number of the elements. We must search for the secret in the Bible, and then in the stars and the spirits. In the second book, Alchymy is the speaker. She points out the mode of performing the processes; and says that to endeavour to fix volatile substances, is the same thing as to endeavour to trace white letters on a wall with a piece of charcoal. She prohibits all long processes, because God created the world in six days.

His method of judging of the diseases from the urine of the patient deserves to be mentioned. He distilled the urine, and fixed to the receiver a tube furnished with a scale, the degrees of which consisted of all the parts of the body. The phenomena which he observed during the distillation of the urine, enabled him to draw inferences respecting the state of all these different organs.

I pass over Bodenstein, Taxites, and Dorn, who distinguished themselves as partisans of Paracelsus. Dorn derived the whole of chemistry from the first chapter of Genesis, the words of which he explained in an alchymistical sense. These words in particular, “And God made the firmament, and divided the waters which were under the firmament from the waters which were above the firmament,” appeared to him to be an account of the great work. Severinus, physician to the King of Denmark, and canon of Roskild, was also a celebrated partisan of Paracelsus; but his writings do not show either that knowledge or stretch of thought which would enable us to account for the reputation which he acquired and enjoyed.

There were very few partisans of Paracelsus out of Germany. The most celebrated of his followers among the French, was Joseph du Chesne, better known by the name of Quercitanus, who was physician to Henry IV. He was a native of Gascony, and drew many enemies upon himself by his arrogant and overbearing conduct. He pretended to be acquainted with the method of making gold. He was a thorough-going Paracelsian. He affirmed that diseases, like plants, spring from seeds. The word alchymy, according to him, is composed of the two Greek words ἁλς (salt) and χημεια, because the great secret is concealed in salt. All bodies are composed of three principles, as God is of three substances. These principles are contained in saltpetre, the salts of sulphur solid and volatile, and the volatile mercurial salt. He who possesses sal generalis may easily produce philosophical gold, and draw potable gold from the three kingdoms of nature. To prove the possibility of this transmutation, he cites an experiment very often repeated after him, and which some theologians have even employed as analogous to the resurrection of the dead; namely, the faculty which plants have of being produced from their ashes. His materia medica is founded on the signatures of plants, which he carries so far as to assert that male plants are more suitable to men, and female plants to women. Sulphuric acid, he says, has a magnetic virtue, in consequence of which it is capable of curing the epilepsy. He recommends the magisterium cranii humani as an excellent medicine, and boasts much of the virtues of antimony.

Du Chesne was opposed by Riolanus, who attacked chemical remedies with much bitterness. The medical faculty of Paris took up the cause of the Galenists with much zeal, and prohibited their fellows and licentiates from using any chemical medicines whatever. He had to sustain a dispute with Aubert relative to the origin and the transmutation of metals. Fenot came to the assistance of Aubert, and affirmed that gold possesses no medical properties whatever, that crabs’ eyes are of no use when administered in intermittents, and that the laudanum of Paracelsus (being an opiate) is in reality hurtful instead of being beneficial.

The decree of the medical faculty of Paris which placed antimony among the poisons, and which occasioned that of the Parliament of Paris, was composed by Simon Pietre, the elder, a man of great erudition and the most unimpeachable probity. Had it been literally obeyed it would have occasioned very violent proceedings; because chemical remedies, as they act more promptly and with greater energy, were getting daily into more general use. In 1603 the celebrated Theodore Turquet de Mayenne was prosecuted, because, in spite of the prohibition, he had sold antimonial preparations. The decree of the faculty against him exhibits a remarkable proof of the bigotry and intolerance of the times.[160] However Turquet does not seem to have been molested notwithstanding this decree. He ceased indeed to be professor of chemistry, but continued to practise medicine as formerly; and two members of the faculty, Seguin and Akakia, even wrote an apology for him. At last he went to England, whither he had been invited, to accept an honourable appointment.

The mystical doctrines of Paracelsus are supposed to have given origin to the sect of Rosecrucians, concerning which so much has been written and so little certain is known. It is not at all unlikely that the greatest part, if not the whole that has been stated about the antiquity, and extent, and importance of this sect, is mere fiction, and that the origin of the whole was nothing else than a ludicrous performance of Valentine Andreæ, an ecclesiastic of Calwe, in the country of Wirtemburg, a man of much learning, genius, and philanthropy. From his life, written by himself, and preserved in the library of Wolfenbuttel, we learn that in the year 1603 he drew up the celebrated Noce Chimique of Christian Rosenkreuz, in order to counteract the alchymistical and the theosophistical dogmas so common at that period. He was unable to restrain his risible faculties when he saw this ludibrium juvenilis ingenii adopted as a true history, while he meant it merely as a satire. It is believed that the Fama Fraternitatis is a production of this ecclesiastic, and that he published it in order to correct the chemists and enthusiasts of the time. He himself was called Andreæ, Knight of the Rose-cross (rosæ crucis) because he had engraven on his seal a cross with four roses.

It is true that Andreæ instituted, in 1620, a fraternitas christiana, but with quite other views than those which are supposed to have actuated the Rosecrucians. His object was to correct the religious opinions of the times, and to separate Christian theology from scholastic controversies, with which it had been unhappily intermixed. He himself, in different parts of his writings, distinguishes carefully between the Rosecrucians and his own society, and amuses himself with the credulity of the German theosophists, who adopted so readily his fiction for a series of truths. It would appear, therefore, that this secret order of Rosecrucians, notwithstanding the brilliant origin assigned to it, really owes its birth to the pleasantry of a clergyman of Wirtemburg, who endeavoured by that means to set bounds to the chimeras of theosophy, but who unfortunately only increased still more the adherents of this absurd science.

A crowd of enthusiasts found it too advantageous to propagate the principles of the rosa crux not to endeavour to unite them into a sect. Valentine Weigel, a fanatical preacher at Tschoppau, near Chemnitz, left at his death a prodigious number of followers, who were already Rosecrucians, without bearing the name. Egidius Gutmann, of Suabia, was equally a Rosecrucian, without bearing the name; he condemned all pagan medicines, and affirmed that he possessed the universal remedy which ennobles man, cures all diseases, and gives man the power of fabricating gold. “To fly in the air, to transmute metals, and to know all the sciences,” says he, “nothing more is requisite than faith.”

Oswald Crollius, of Hesse, must also take his station in this honourable fraternity of enthusiasts. He was physician to the Prince of Anhalt, and afterwards a counsellor of the Emperor Rodolphus II. The introduction to his Basilica Chymica, contains a short but exact epitome of the opinions of Paracelsus. It is not worth while to give the reader a notion of his own opinions, which are quite as absurd and unintelligible as those of Paracelsus and his followers. As a preparer of chemical medicines he deserves more credit; antimonium diaphoreticum was a favourite preparation of his, and so was sulphate of potash, which was known at the time by the name of specificum purgans Paracelsi: he knew chloride of silver well, and first gave it the name of luna cornea, or horn silver: fulminating gold was known to him, and called by him aurum volatile.

This is the place to mention Andrew Libavius, of Halle, in Saxony, where he was a physician, and a professor in the gymnasium of Coburg, who was one of the most successful opponents of the school of Paracelsus, and whose writings do him much credit. As a chemist, he deserves perhaps to occupy a higher rank than any of his contemporaries: he was, it is true, a believer in the possibility of transmuting metals, and boasted of the wonderful powers of aurum potabile; but he always distinguishes between rational alchymy and the mental alchymy of Paracelsus. He separated, with great care, chemistry from the reveries of the theosophists, and stands at the head of those who opposed most successfully the progress of superstition and fanaticism, which was making such an overwhelming progress in his time. His writings are very numerous and various, and were collected and published at Frankfort, in 1615, in three folio volumes, under the title of “Opera omnia Medico-chymica.” Libavius himself died in 1616. It would occupy more space than we have room for, to attempt an abstract of his very multifarious works. A few observations will be sufficient: he wrote no fewer than five different tracts to expose the quackery of George Amwald, who had boasted that he was in possession of a panacea, by means of which he was enabled to perform the most wonderful cures, and which he was in the habit of selling to his patients at an enormous price; Libavius showed that this boasted panacea was nothing else than cinnabar, which neither possessed the virtues ascribed to it by Amwald, nor deserved to be purchased at so high a price. He entered also into a controversy with Crollius, and exposed his fanatical and absurd opinions. He engaged likewise in a dispute with Henning Scheunemann, a physician in Bamberg, who was a Rosecrucian, and, like the rest of his brethren, profoundly ignorant not merely of all science, but even of philology. The expressions of Scheunemann are so obscure, that we learn more of his opinions from Libavius than from his own writings. He divides the internal nature of man into seven different degrees, from the seven changes it undergoes: these are, combustion, sublimation, dissolution, putrefaction, distillation, coagulation, and tincture. He gives us likewise an account of ten modifications which the three elements undergo; but as they are quite unintelligible, it is not worth while to state them. Libavius had the patience to analyze and expose all these gallimatias.

Libavius’s system of chemistry, entitled “Alchymia è dispersis passim optimorum auctorum, veterum et recentiorum exemplis potissimum, tum etiam preceptis quibusdam operose collecta, adhibitisque ratione et experientia quanta potuit esse methodo accurate explicata et in integrum corpus redacta. Accesserunt tractati nonnulli physici chymici item methodistici.” Frankfort, 1595, folio, 1597, 4to.—is really an excellent book, considering the period in which it was written, and deserves the attention of every person who is interested in the history of chemistry. I shall notice some of the most remarkable chemical facts which occur in Libavius, and which I have not observed in any preceding writer; who the actual discoverer of these facts really was, it is impossible to say, in consequence of the secrecy which at that time was affected, and the obscure terms in which chemical facts are in general stated.

He was aware that the fumes of sulphur have the property of blackening white lead. He was in the habit of purifying cinnabar by means of arsenic and oxide of lead. He knew the method of giving glass a red colour by means of gold or its oxide, and was aware of the method of making artificial gems, such as ruby, topaz, hyacinth, garnet, balass, by tinging glass by means of metallic oxides. He points out fluor spar as an excellent flux for various metals and their oxides. He knew that when metals were fused along with alkaline bodies, a certain portion of them was converted into slags, and this portion he endeavoured to recover by the addition of iron filings. He was aware of the mode of acidifying sulphur by means of nitric acid. He knew that camphor is soluble in nitric acid, and forms with it a kind of oil. Of the perchloride of tin he was undoubtedly the discoverer, as it has continued ever since his time to pass by his name; namely, fuming liquor of Libavius. He was aware, that alcohol or spirits could be obtained by distilling the fermented juice of a great variety of sweet fruits. He procured sulphuric acid by the distillation of alum and sulphate of iron, as Geber had done long before his time; but he determined the nature of the acid with more care than had been done, and showed, that it was the same as that obtained by the combustion of sulphur along with saltpetre. To him, therefore, in some measure, are we indebted for the process of preparing sulphuric acid which is at present practised by manufacturers.

Libavius found a successor in Angelus Sala, of Vicenza, physician to the Duke of Mecklenburg-Schwerin, worthy of his enlightened views and indefatigable exertions to oppose the torrent of fanaticism which threatened to overwhelm all Europe. Sala was still more addicted to chemical remedies than Libavius himself; but he had abjured a multitude of prejudices which had distinguished the school of Paracelsus. He discarded aurum potabile, and considered fulminating gold as the only remedy of that metal that deserved to be prescribed by medical men. He treated the notion of the existence of a universal remedy with contempt. He described sulphuret of gold and glass of antimony with a good deal of precision. He recommended sulphuric acid as an excellent remedy, and showed that it might be formed indifferently from sulphur, or by distilling blue vitriol or green vitriol. He affirmed, that the essential salts obtained from plants had not the same virtues as the plants from which they are obtained. He showed that sal ammoniac is a compound of muriatic acid and ammonia. To him, therefore, we are indebted for the first accurate mention of ammonia. It could not but have been noticed before by chemists, as it is procured with so much ease by the distillation of animal substances; but Sala is the first person who seems to have examined it with attention, and to have recognised its peculiar properties, and the readiness with which it saturates the different acids. He showed that iron has the property of precipitating copper from acid solutions: he pointed out also various precipitations of metals by other metals. He seems to have been acquainted with calomel, and to have been aware of at least some of its medical properties. He says, that fulminating gold loses its fulminating property when mixed with its own weight of sulphur, and the sulphur is burnt off it. Many other curious chemical facts occur in his writings, which it would be too tedious to particularize here. His works were collected and published in a quarto volume at Frankfort, in 1647, under the title of “Opera Medico-chymica, quæ extant omnia.” There was another edition in the same place in 1682, and an edition was published at Rome in 1650.

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CHAPTER V.
OF VAN HELMONT AND THE IATRO-CHEMISTS.

Paracelsus first raised the dignity of chemistry, by pointing out the necessity of it for medical men, and by showing the superiority of chemical medicines over the disgusting decoctions of the Galenists. Libavius and Angelus Sala had carefully separated chemistry from the fanatical opinions of the followers of Paracelsus and the Rosecrucians. But matters were not doomed to remain in this state. Chemistry underwent a new revolution at this period, which shook the Spagirical system to its foundation; substituted other principles, and gave to medicine an aspect entirely new. This revolution was in a great measure due to the labours of Van Helmont.

John Baptist Van Helmont was a gentleman of Brabant, and Lord of Merode, of Royenboch, of Oorschot, and of Pellines. He was born in Brussels in 1577, and studied scholastic philosophy in Louvain till the age of seventeen. After having finished his humanity (as it was termed), he ought, according to the usage of the place, to have taken his degree of master of arts; but, having reflected on the futility of these ceremonies, he resolved never to solicit any academical honour. He next associated himself to the Jesuits, who then delivered courses of philosophy at Louvain, to the great displeasure of the professors of that city. One of the most celebrated of the Jesuits, Martin del Rio, even taught him magic. But Van Helmont was disappointed in his expectations: instead of that true wisdom which he hoped to acquire, he met with nothing but scholastic dialectics, with all its usual subtilties. He was no better satisfied with the doctrines of the Stoics, who taught him his own weakness and misery.

At last the works of Thomas à Kempis, and John Taulerus fell into his hands. These sacred books of mysticism attracted his attention: he thought that he perceived that wisdom is the gift of the Supreme Being; that it must be obtained by prayer; and that we must renounce our own will, if we wish to participate in the influence of the divine grace. From this moment he imitated Jesus Christ, in his humility. He abandoned all his property to his sister, renouncing the privileges of his birth, and laying aside the rank which he had hitherto occupied in society. It was not long before he reaped the fruit of these abnegations. A genius appeared to him in all the important circumstances of his life. In the year 1633 his own soul appeared to him under the figure of a resplendent crystal.

The desire which he had of imitating in every respect the conduct of Christ, suggested to him the idea of practising medicine as a work of charity and benevolence. He began, as was then the custom of the time, by studying the art of healing in the writings of the ancients. He read the works of Hippocrates and Galen with avidity; and made himself so well acquainted with their opinions, that he astonished all the medical men by the profundity of his knowledge. But as his taste for mysticism was insatiable, he soon became disgusted with the writings of the Greeks; an accident led him to abandon them for ever. Happening to take up the glove of a young girl afflicted with the itch, he caught that disagreeable disease. The Galenists whom he consulted, attributed it to the combustion of the bile, and the saline state of the phlegm. They prescribed a course of purgatives which weakened him considerably, without effecting a cure. This circumstance disgusted him with the system of the humorists, and led him to form the resolution of reforming medicine, as Paracelsus had done. The works of this reformer, which he read with attention, awakened in him a spirit of reformation, but did not satisfy him; because his knowledge, being much greater than that of Paracelsus, he could not avoid despising the disgusting egotism, and the ridiculous ignorance of that fanatic. Though he had already refused a canonicate, he took the degree of doctor of medicine, in 1599, and afterwards travelled through the greatest part of France and Italy; and he assures us, that during his travels, he performed a great number of cures. On his return, he married a rich Brabantine lady, by whom he had several children; among others a son, afterwards celebrated under the name of Francis Mercurius, who edited his father’s works, and who went a good deal further than his father had done, in all the branches of theosophy. Van Helmont passed the rest of his life on his estate at Vilvorde, almost constantly occupied with the processes of his laboratory. He died in the year 1644, on the 13th of December, at six o’clock in the evening, after having nearly reached the age of sixty-seven years.

The system of Van Helmont has for its basis the opinions of the spiritualists. He arranged even the influence of evil genii, the efforts of sorcerers, and the power of magicians among the causes which produce diseases. The archeus of Paracelsus constituted one of the capital points of his theory; but he ascribed to it a more substantial nature than Paracelsus had done. This archeus is independent of the elements; it has no form; for form constitutes the object of generation, or of production. These ideas are obviously borrowed from the ancients. The form of Aristotle is not the μορφη, but the ενεργεια (the power of acting) which matter does not possess.

The archeus draws all the corpuscles of matter to the aid of fermentation. There are, properly speaking, only two causes of things; the cause ex qua, and the cause per quam. The first of these causes is water. Van Helmont considered water as the true principle of every thing which exists; and he brought forward very specious arguments in favour of his opinion, drawn both from the animal and vegetable kingdom. The reader will find his arguments on the subject, in his treatise entitled “Complexionum atque Mistionum elementalium Figmentum.”[161] The only one of his experiments that, in the present state of our knowledge, possesses much plausibility, is the following: He took a large earthen vessel, and put into it 200 lbs. of earth, previously dried in an oven. This earth he moistened with rain-water, and planted in it a willow which weighed five pounds. After an interval of five years, he pulled up his willow and found that its weight amounted to 169 pounds, and about three ounces. During these five years, the earth in the pot was duly watered with rain or distilled water. To prevent the earth in which the willow grew from being mixed with new earth blown upon it by the winds, the pot was covered with tin plate, pierced with a great number of holes to admit the air freely. The leaves which fell every autumn during the vegetation of the willow in the pot, were not reckoned in the 169 lbs. 3 oz. The earth in the pot being again dried in the oven, was found to have lost about two ounces of its original weight. Thus 164 lbs. of wood, bark, roots, &c., were produced from water alone.[162] This, and several other experiments which it is needless to state, satisfied him that all vegetable substances are produced from water alone. He takes it for granted that fish live (ultimately at least) on water alone; but they contain almost all the peculiar animal substances that exist in the animal kingdom. Hence he concludes that animal substances are derived also from pure water.[163] His reasoning with respect to sulphur, glass, stone, metals, &c., all of which he thinks may ultimately be resolved into water, is not so satisfactory.

Water produces elementary earth, or pure quartz; but this elementary earth does not enter into the composition of organic bodies. Van Helmont excludes fire from the number of elements, because it is not a substance, nor even the essential form of a substance. The matter of fire is compound, and differs entirely from the matter of light. Water gives origin also to the three chemical principles, salt, sulphur, and mercury, which cannot be considered as elements or active principles. I do not see clearly how he gets rid of air; for he says, that though water may be elevated in the form of vapour, yet that these vapours are no more air than the dust of marble is water.

According to Van Helmont, a particular disposition of matter, or a particular mixture of that matter is not necessary for the formation of a body. The archeus, by its sole power, draws all bodies from water, when the ferment exists. This ferment, in its quality of a mean which determines the action of the archeus, is not a formal being; it can neither be called a substance, nor an accident. It pre-exists in the seed which is developed by it, and which contains in itself a second ferment of the seed, the product of the first. The ferment exhales an odour, which attracts the generating spirit of the archeus. This spirit consists in an aura vitalis, and it creates the bodies of nature in its own image, after its own idea. It is the true foundation of life, and of all the functions of organized bodies; it disappears only at the instant of death to produce a new creation of the body, which enters then, for the second time, into fermentation. The seed, then, is not indispensable to enable an animal to propagate its species; it is merely necessary that the archeus should act upon a suitable ferment. Animals produced in this manner are as perfect as those which spring from eggs.

When water, as an element, ferments, it develops a vapour, to which Van Helmont gave the name of gas, and which he endeavours to distinguish from air. This gas contains the chemical principles of the body from which it escapes in an aerial form by the impulse of the archeus. It is a substance intermediate between spirit and matter, the principle of action of life, and of generation of all bodies; for its production is the first result of the action of the vital spirit on the torpid ferment, and it may be compared to the chaos of the ancients.

The term gas, now in common use among chemists, and applied by them to all elastic fluids which differ in their properties from common air, was first employed by Van Helmont: and it is evident, from different parts of his writings, that he was aware that different species of gas exist. His gas sylvestre was evidently our carbonic acid gas, for he says, that it is evolved during the fermentation of wine and beer; that it is formed when charcoal is burnt in air; and that it exists in the Grotto del Cane. He was aware that this gas extinguishes a lighted candle. But he says that the gases from dung, and those formed in the large intestines, when passed through a candle, catch fire, and exhibit a variety of colours, like the rainbow.[164] To these combustible gases he gave the names of gas pingue, gas siccum, gas fuliginosum, or endimicum.

Sal ammoniac, he says, may be distilled alone, without danger, and so may aqua fortis (aqua chrysulca), but if they be mixed together so much gas sylvestre is produced, that the vessels employed, however strong, will burst asunder, unless an opening be left for the escape of this gas.[165] In the same way cream of tartar cannot be distilled in close vessels without breaking them in pieces, an opening must be left for the escape of the gas sylvestre, which is generated in such abundance.[166] He says, also, that when carbonate of lime is dissolved in distilled vinegar, or silver in nitric acid, abundance of gas sylvestre is extricated. From these, and many other passages which might be quoted, it is evident that Van Helmont was aware of the evolution of gas during the solution of carbonates and metals in acids, and during the distillation of various animal and vegetable substances, that he had anticipated the experiments made so many years after by Dr. Hales, and for which that philosopher got so much credit. But it would be going too far to say, as some have done, that Van Helmont knew accurately the differences which characterize the different gases which he produced, or indeed that he distinguished accurately between them. For it is evident, from the passages quoted and from many others which occur in his treatise, De Flatibus, that carbonic acid, protoxide of azote, and deutoxide of azote, and probably also muriatic acid gas were all considered by him as constituting one and the same gas. How, indeed, could he distinguish between different gases when he was not acquainted with the method of collecting them, or of determining their properties? These observations of Van Helmont, then, though they do him much credit, and show how far his chemical knowledge was superior to that of the age in which he lived, take nothing from the merit or the credit of those illustrious chemists who, in the latter half of the eighteenth century, devoted themselves to the investigation of this part of chemistry, at that time attended with much difficulty, but intimately connected with the subsequent progress which the science has made.

Van Helmont was aware, also, that the bulk of air is diminished when bodies are burnt in it. He considered respiration to be necessary in this way: the air was drawn into the blood by the pulmonary arteries and veins, and occasioned a fermentation in it requisite for the continuance of life.

Gas, according to Van Helmont, has an affinity with the principle of the movement of the stars, to which he gave the name of blas. It had, he supposed, much influence on all sublunary bodies. He admitted in the ferment which gives birth to plants, a substance which, after the example of Paracelsus, he called pessas, and to the metallic ferment he gave the name of bur.[167]

The archeus of Van Helmont, like that of Paracelsus, has its seat in the stomach. It is the same thing as the sentient soul. This notion of the nature and seat of the archeus was founded on the following experiment: He swallowed a quantity of aconitum (henbane). In two hours he experienced the most disagreeable sensation in his stomach. His feeling and understanding seemed to be concentrated in that organ, for he had no longer the free use of his mental faculties. This feeling induced him to place the seat of understanding in the stomach, of volition in the heart, and of memory in the brain. The faculty of desire, to which the ancients had assigned the liver as its organ, he placed in the spleen. What confirmed him still more in the idea that the stomach is the seat of the soul, is the fact, that life sometimes continues after the destruction of the brain, but never, he alleges, after that of the stomach. The sentient soul acts constantly by means of the vital spirits, which are of a resplendent nature, and the nerves serve merely to moisten these spirits which constitute the mediums of sensation. By virtue of the archeus man is much nearer to the realm of spirits and the father of all the genii, than to the world. He thinks that Paracelsus’s constant comparison of the human body with the world is absurd. Yet Van Helmont, at least in his youth, was a believer in magnetism, which he employed as a method of explaining the effect of sympathy.

The archeus exercises the greatest influence on digestion, and he has chiefly the stomach and spleen under his superintendence. These two organs form a duumvirate in the body; for the stomach cannot act alone and without the concurrence of the spleen. Digestion is produced by means of an acid liquor, which dissolves the food, under the superintendence of the archeus. Van Helmont assures us that he had himself tasted this acid liquor in the stomach of birds. Heat, strictly speaking, does not favour digestion; for we see no increase of the digestive powers during the most ardent fever. Nor are the powers of digestion wanting in fishes, although they want the animal heat which is requisite for mammiferous animals. Certain birds even digest fragments of glass, which, certainly, simple heat would not enable them to do. The pylorus is, in some measure, the director of digestion. It acts by a peculiar and immaterial power, in virtue of a blas, and not as a muscle. It opens and shuts the stomach according to the orders of the archeus. It is in it, therefore, that the causes of derangement of digestion must be sought for.

The duumvirate just spoken of is the cause of natural sleep, which does not belong to the soul, as far as it resides in the stomach. Sleep is a natural action, and one of the first vital actions. Hence the reason why the embryo sleeps without ceasing. At any rate it is not true that sleep is owing to vapours which mount to the brain. During sleep the soul is naturally occupied, and it is then that the deity approaches most intimately to man. Accordingly, Van Helmont informs us, that he received in dreams the revelation of several secrets, which he could not have learnt otherwise.

The duumvirate operates the first digestion, of which, Van Helmont enumerates six different species. When the acid, which is prepared for digestion, passes into the duodenum it is neutralized by the bile of the gall-bladder. This constitutes the second digestion. To the bile of the gall-bladder, Van Helmont gave the name of fel, and he carefully distinguished it from the biliary principle in the mass of the blood. This last he called bile. The fel is not an excrementitious matter, but a humour necessary to life, a true vital balsam. Van Helmont endeavoured to show by various experiments that it is not bitter.

The third digestion takes place in the vessels of the mesentery, into which the gall-bladder sends the prepared fluid. The fourth digestion is operated in the heart, where the red blood becomes more yellow and more volatile by the addition of the vital spirits. This is owing to the passage of the vital spirit from the posterior to the anterior ventricle, through the pores of the septum. At the same time the pulse is produced, which of itself develops heat; but does not regulate it in any manner, as the ancients pretended that it did. The fifth digestion consists in the conversion of the arterial blood into vital spirit. It takes place principally in the brain, but is produced also throughout all the body. The sixth digestion consists in the elaboration of the nutritive principle in each member, where the archeus prepares its own nourishment by means of the vital spirits. Thus, there are six digestions: the number seven has been chosen by nature for a state of repose.

From the preceding sketch of the physiology of Van Helmont, it is evident that he paid little or no regard to the structure of the parts in explaining the functions. In his pathology we find the same passion for spiritualism. He admitted, indeed, the importance of anatomy, but he regretted that the pathological part of that science had been so little cultivated. As the archeus is the foundation of life and of all the functions, it is plain that the diseases can neither be derived from the four cardinal humours, nor from the disposition or the action of opposite things; the proximate cause of diseases must be sought for in the sufferings, the anger, the fear, and the other affections of the archeus, and their remote cause may be considered as the ideal seed of the archeus. Disease, in his opinion, is not a negative state or a mere absence of health, it is a substantial and active thing as well as a state of health. Most of the diseases which attack certain parts or members of the body result from an error in the archeus, who sends his ferment from the stomach in which he resides into the other parts of the body. Van Helmont explained in this way not only the epilepsy and madness, but likewise the gout, which does not proceed from a flux, and has not its seat in the limb in which the pain resides, but is always owing to an error in the vital spirit. It is true that the character of the gout acts upon the semen in which the vital spirit principally manifests its action, and that in this way diseases are propagated in the act of generation; but if, during life instead of altering the semen it is carried to the liquid of the articulations, this is a proof of the prudence of nature, which lavishes all her cares on the preservation of the species, and loves better to alter the humours of the articulations than the semen itself. The gout acidifies the liquors of the articulations, which is then coagulated by the acids. The duumvirate is the cause of apoplexy, vertigo, and particularly of a species of asthma, which Van Helmont calls caducus pulmonalis. Pleurisy is produced in a similar way. The archeus, in a movement of rage, sends acrid acids to the lungs, which occasion an inflammation. Dropsy is also owing to the anger of the archeus, who prevents the secretions of the kidneys from going on in the usual way.

Of all the diseases, fever appeared to him most conformable to his notions of the unlimited power of the archeus. The causes of fever are all much more proper to offend the archeus, than to alter the structure of parts and the mixture of humours. The cold fit is owing to a state of fear and consternation, into which the archeus is thrown, and the hot stage results from his disordered movements. All fevers have their peculiar seat in the duumvirate.

Van Helmont was in general much more successful in refuting the scholastic opinions by which the practice of medicine was regulated in his time, than in establishing his own. We are struck with the force of his arguments against the Galenical doctrine of fever, and against the influence of the cardinal humours on the different kinds of fever. He refuted no less vehemently the idea of the putridity of the blood, while that liquid circulates in the vessels. Perhaps he carried the opposite doctrine too far; but his opinions have had a good effect upon subsequent medical theory, and medical men learned from them to make less use of the term putridity. The phrase mixture of humours, not more intelligible, however, came to be substituted for it.

Van Helmont’s theory of urinary calculi deserves peculiar attention, because it exhibits the germ of a more rational explanation of these concretions than had been previously attempted by physiologists. Van Helmont was aware that Paracelsus, who ascribed these concretions to tartar, had formed an idea of their nature, which a careful chemical analysis would immediately refute. He satisfied himself that urinary calculi differ completely from common stones, and that they do not exist in the food or drink which the calculous person had taken. Tartar, he says, precipitates from wine, not as an earth, but as a crystallized salt. In like manner, the natural salt of urine precipitates from that liquid, and gives origin to calculi. We may imitate this natural process by mixing spirit of urine with rectified alcohol. Immediately an offa alba is precipitated.

It is needless to observe that Van Helmont was mistaken, in supposing that this offa was the matter of calculus. Spirit of urine was a strong solution of carbonate of ammonia. The alcohol precipitated this salt; so that his offa was merely carbonate of ammonia. Nor is there the shadow of evidence that alcohol, as Van Helmont thought it did, ever makes its way into the mass of humours; yet his notion of the origin of calculi is not less accurate, though of course he was ignorant of the chemical nature of the various substances which constitute these calculi. From this reasoning Van Helmont was induced to reject the term tartar, employed by Paracelsus. To avoid all false interpretations he substitutes the word duelech, to denote the state in which the spirit of urine precipitates and gives origin to these calculous concretions.

As all diseases proceeded in his opinion from the archeus, the object of his treatment was to calm the archeus, to stimulate it, and to regulate its movements. To accomplish these objects he relied upon dietetics, and upon acting on the imaginations of his patients. He considered certain words as very efficacious in curing the diseases of the archeus. He admitted the existence of the universal medicine, to which he gave the names of liquor alkahest, ens primum salium, primus metallus. Mercurials, antimonials, opium, and wine, are particularly agreeable to the archeus, when in a state of delirium from fever.

Among the mercurial preparations, he praises what he calls mercurius diaphoreticus as the best. He gives no account of the mode of preparing it; but from some circumstances I think it must have been calomel. He considers it as a sovereign remedy in fevers, dropsies, diseases of the liver, and ulcers of the lungs. He employed the red oxide of mercury as an external application to ulcers. The principal antimonial preparations which he employed were the hydrosulphuret, or golden sulphur, and the deutoxide, or antimonium diaphoreticum. This last medicine was used in scruple doses—a proof of its great inertness compared with the protoxide of antimony.

Opium he considered as a fortifying and calming medicine. It contains an acrid salt and a bitter oil, which give it the virtue of putting a stop to the errors of the archeus, when it was sending its acid ferment into other acid parts of the body. Van Helmont assures us that he wrought many important cures by the employment of wine.

Such is a very short statement of the opinions of a man, who, notwithstanding his attachment to the fanatical opinions which distinguished the time in which he lived, had the merit of overturning a vast number of errors, both theoretical and practical; and of laying down many principles, which, for want of erudition, have been frequently assigned to modern writers. Van Helmont has been frequently placed on the same level with Paracelsus, and treated like him with contempt. But his claims upon the medical world are much higher, and his merits infinitely greater. His notions, it is true, were fanatical; but his erudition was great, his understanding excellent, and his industry indefatigable. His writings did not become known till rather a late period; for, with the exception of a single tract, they were not published till 1648, by his son, after his death.

The decided preference given to chemical medicines by Van Helmont, and the uses to which he applies chemical theory, had a natural tendency to raise chemistry to a higher rank in the eyes of medical men than it had yet reached. But the man to whom the credit of founding the iatro-chemical sect is due, is Francis de le Boé Sylvius, who was born in the year 1614. While a practitioner of medicine at Amsterdam, he studied with profound attention the system of Van Helmont, and the rival and much more popular theory of Descartes: upon these he founded his own theory, which, in reality, contains little entitled to the name of original, notwithstanding the tone in which he speaks of it, and his repeated declarations that he had borrowed from no one. He was appointed professor of the theory and practice of medicine in the University of Leyden, where he taught with such eclat, and drew after him so great a number of pupils, that Boerhaave alone surpassed him in this respect. It was he that first introduced the practice of giving clinical lectures in the hospitals, on the cases treated in the presence of the pupils. This admirable innovation has been productive of much benefit to medicine. He greatly promoted anatomical studies, and inspected, himself, a vast number of dead bodies. This is the more remarkable, because his own system, like that of Van Helmont, from whom it was borrowed, was quite independent of the structure of the parts.

Every thing was explained by him according to the principles of chemistry, as they were then understood. The celebrity of the university in which he taught, and the vast number of his pupils, contributed to spread this theory into every part of the world, and to give it an eclat which is really surprising, when we consider it with attention. But he possessed the talents just suited for securing the reception of his opinions by his pupils as infallible oracles, and of being the idol of the university. Yet it is melancholy to be obliged to add, that few persons ever more abused the favours of nature, or the advantages of situation and elocution.

To form a clear idea of the principles of this founder of iatro-chemistry, we have only to call to mind the ferments of Van Helmont, which constitute the foundation-stone of the whole system. We cannot, says he, conceive a single change in the mixture of the humours, which is not the consequence of fermentation; and yet he assigns to this fermentation conditions which are scarcely to be found united in the living body. Digestion, in his opinion, is a true fermentation produced by the application of a ferment. Like Van Helmont, he admits a triumvirate; but places it in the humours; the effervescence or fermentation of which enabled him to explain most of the functions of the body. Digestion is the result of the mixture of the saliva with the pancreatic juice and the bile, and the fermentation of these humours. The saliva, as well as the pancreatic juice, contains an acidulous salt easily recognised by the taste. Here Sylvius derives advantage from the experiments of Regnier de Graaf on the pancreatic juice, which he had constantly found acid.

Sylvius, who affirmed that the bile contained an alkali, united with an oil and a volatile spirit, supposes an effervescence from the union of the alkali of the bile with the acid of the pancreatic juice, and this fermentation he considered as the cause of digestion. By this fermentation the chyle is produced, which is nothing else than the volatile spirit of the food accompanied by an oil and an alkali, neutralized by a weak acid. The blood is more than completed (plus quam perficitur) in the spleen. It acquires its highest perfection by the addition of a certain quantity of vital spirits. The bile is not drawn from the blood in the liver, but pre-exists in the circulating fluid. It mixes with that fluid anew to be carried to the heart together with the lymph, equally mixed with the blood, and there it gives origin to a vital fermentation. In this way the blood becomes the centre of reunion of all the humours of the secretions, which mix together or separate, without the solids taking the smallest share in the operations. Indeed, so completely are the solids banished from the system of Sylvius that he attends to nothing whatever except the humours.

The formation and motion of the blood is explained by the fermentation of the oily volatile salt of the bile, and the dulcified acid of the lymph, which develops the vital heat, by which the blood is attenuated and becomes capable of circulating. This vital fire, quite different from ordinary fire is kept up in its turn by the uniform mixture of the blood. It attenuates the humours, not because it is heat but because it is composed of pyramids. This last notion is obviously borrowed from Descartes, just as the fermentation in the heart, as the cause of the motion of the blood, reminds us of the opinions of Van Helmont.

Sylvius explains the preparation of the vital spirits in the encephalos by distillation, and he finds a great resemblance between their properties and those of spirit of wine. The nerves conduct these spirits to the different parts, and they spread themselves in the substance of the organs to render them sensible. When they insinuate themselves into the glands the addition of the acid of the blood produces a liquid analogous to naphtha, which constitutes the lymph. Lymph, then, is a compound of the vital spirit and the acid of the blood. Milk is formed in the mammæ by the afflux of a very mild acid, which gives a white colour to the red humour of the blood.

The theory of the natural functions was no less chemical. Even the diseases themselves were explained upon chemical principles. Sylvius first introduced the word acridity to denote a predominance of the chemical elements of the humours, and he looked upon these acridities as the proximate cause of all diseases. But as every thing acrid may be referred to one or other of two classes, acids and alkalies, there are only two great classes of diseases; namely, those proceeding from an acid acridity, and those proceeding from an alkaline.

Sylvius was not altogether ignorant of the constituent parts of the animal humours; but it is obvious, from the account of his opinions just given, that this knowledge was very incomplete; indeed the whole of his chemical science resolves itself into a comparison of the humours of the living body with chemical liquids. Perhaps his notions respecting such of the gases, as he had occasion to observe, were somewhat clearer than those of Van Helmont. He called them halitus, and takes some notice of their different chemical properties, and states the influence which he supposes them to exert in certain diseases.

In the human body he saw nothing but a magna of humours continually in fermentation, distillation, effervescence, or precipitation; and the physician was degraded by him to the rank of a distiller or a brewer.

Bile acquires different acridities, when bad food, altered air, or other similar causes act apon the body. It becomes acid or alkaline. In the former case it thickens and occasions obstructions; in the latter it excites febrile heat; and the viscid vapours elevated from it are the cause of the cold fit with which fever commences. All acute and continued fevers have their origin in this acridity of the bile. The vicious mixture of the bile with the blood, or its specific acridity, produces jaundice, which is far from being always owing to obstructions in the liver. The vicious effervescence of the bile with the pancreatic juice produces almost all other diseases. But all these assertions of Sylvius are unsupported by evidence.

The acid acridity of the pancreatic juice, and the obstruction of the pancreatic ducts, which are produced by it, are considered by him as the cause of intermittent fevers. When the acid of the pancreatic juice acquires still more acridity, hypochondriasis and hysteria are the consequences of it. If, during the morbid effervescence of the pancreatic juice with the bile an acid and viscid humour arise, the vital spirits of the heart are overwhelmed during a certain time. This occasions syncope, palpitation of the heart, and other nervous affections.

When the acid acridity of the pancreatic juice or of the lymph (for both are similar) is deposited on the nerves, the consequence is spasms or convulsions; epilepsy in particular depends upon the acrid vapours produced by the morbid effervescence of the pancreatic juice with acrid bile. Gout has the same origin as intermittent fevers, for we must look for it in the obstruction of the pancreas and the lymphatic glands, accompanied with an acid acridity of the lymph. Rheumatism is owing to the acrid acid, deprived of the oil which dulcifies it. The smallpox is occasioned by an acid acridity in the lymph, which gives origin to the pustules. Indeed all suppuration in general is owing to a coagulating acid in the lymph. Syphilis results from a caustic acid in the lymph. The itch is produced by an acid acridity of the lymph. Dropsies are produced by the same acid acridity of the lymph. Urinary calculi are the consequences of a coagulating acid existing in the lymph and the pancreatic juice. Corrosive acids, and the loss of volatile spirits, occasion leucorrhœa.

From the preceding statement it would appear that almost all diseases proceed from acids. However, Sylvius informs us that malignant fevers are owing to a superabundance of volatile salts and to a too great tenuity of the blood. The vital spirits themselves give occasion to diseases. They are sometimes too aqueous, sometimes they effervesce too violently, and sometimes not at all. Hence all the nervous diseases, which Sylvius never considers as existing by themselves; but as always derived from the acid, acrid, or alkaline vapours which trouble the vital spirits.

The method of cure which Sylvius deduced from these absurd and contemptible hypotheses, was worthy of the hypotheses themselves; and certainly constitute the most detestable mode of treatment that ever has disgraced medical science. To diseases produced by the effervescence of the bile he opposed purgatives; because in his opinion emetics produced injurious effects. The reason was, that the emetics which he employed were too violent, consisting of antimonial preparations, particularly powder of Algerotti, or an impure protoxide of antimony. For though emetic tartar had been discovered in 1630, it does not seem to have come into use till a much later period. We do not find any notice of it in the praxis chymiatrica of Hartmann published in 1647, at Geneva.

He endeavoured to moderate the acridity of the bile by opiates and other narcotics. It will scarcely be believed, though it was a natural consequence of his opinions, when we state that he recommended ammoniacal preparations, particularly his oleaginous volatile salt, and spirit of hartshorn, &c., as cures for almost all diseases. Sometimes they were employed to correct the acidity of the lymph, sometimes to destroy the acid acridity of the pancreatic juice, sometimes to correct the inertness of the vital spirits, sometimes to promote the secretions, and to induce a flow of the menses. Volatile spirit of amber and opium were prescribed by him in intermittent fevers; and volatile salts in almost all acute diseases. He united them with antivenomous potions, angelica, contrayerva, bezoard, crabs’ eyes, and other similar substances. These absorbents seemed to him very necessary to correct the acidity of the pancreatic juice, and the acridity of the bile. In administering them he paid no attention to the regular course which acute diseases usually run; he neither inquired into the remote nor proximate causes of disease, nor to the symptoms: every thing was neglected connected with induction, and his whole proceedings regulated by wild speculations and absurd theories, quite inconsistent with the phenomena of nature.

To attempt to refute these wild notions of Sylvius would be loss of time. It is extraordinary, and almost incredible, that he could have regulated his practice by them: and it is a still more incredible thing, and exhibits a very humiliating view of human nature, that these crudities and absurdities were swallowed with avidity by crowds of students, who placed a blind reliance on the dogmas of their master, and were initiated by him into a method of treating their patients, better calculated than any other that could easily have been devised, to aggravate all their diseases, and put an end to their lives. If any of the patients of the iatro-chemists ever recovered their health, well might it be said that their recovery was not the consequence of the prescriptions of their physicians, but that it took place in spite of them.[168]

It is a very remarkable circumstance, and shows clearly that mankind in general had become disgusted with the dogmas of the Galenists, that iatro-chemistry was adopted more or less completely by almost all physicians. There were, indeed, a few individuals who raised their voices against it; but, what is curious and inexplicable, they never attempted to start objections against the principles of the iatro-chemists, or to point out the futility of their hypothesis, and their inconsistency with fact. They combated them by arguments not more solid than those of their antagonists.

During the presidency of Riolan over the Medical College of Paris, that learned body set itself against all innovations. Guy Patin, who was a medical professor in the University of Paris, and a man of great celebrity, opposed the chemical system of medicine with much zeal. In his Martyrologium Antimonii he collects all the cases in which the use of antimony, as a medicine, had proved injurious to the patient. But in the year 1666, the dispute relative to antimony, and particularly relative to tartar emetic, became so violent, that all the doctors of the faculty of Paris were assembled by an order of the parliament, under the presidency of Dean Vignon, and after a long deliberation, it was concluded by a majority of ninety-two votes, that tartar emetic, and other antimonials, should not only be permitted, but even recommended. Patin after this decision pretended no longer to combat chemical medicine; but he did not remain inactive. One of his friends, Francis Blondel, demanded the resolution to be cancelled; but his exertions were unsuccessful; nor were the writings of Guillemeau and Menjot, who were also keen partisans of the views of Patin, attended with better success.

In England iatro-chemistry assumed a direction quite peculiar. It was embraced by a set of men who had cultivated anatomy with the most marked success, and who were quite familiar with the experimental method of investigating nature. The most eminent of all the English supporters of iatro-chemistry was Thomas Willis, who was a contemporary of Sylvius.

Dr. Willis was born at Great Bodmin, in Wiltshire, in 1621. He was a student at Christchurch College, in Oxford, when that city was garrisoned for King Charles I. Like the other students, he bore arms for his Majesty, and devoted his leisure hours to the study of physic. After the surrender of Oxford to the parliament, he devoted himself to the practice of medicine, and soon acquired reputation. He appropriated a room as an oratory for divine service, according to the forms of the church of England, to which most of the loyalists of Oxford daily resorted. In 1660, he became Sedleian professor of natural philosophy, and the same year he took the degree of doctor of physic. He settled ultimately in London, and soon acquired a higher reputation, and a more extensive practice, than any of his contemporaries. He died in 1675, and was buried in Westminster Abbey. He was a first-rate anatomist. To him we are indebted for the first accurate description of the brain and nerves.

But it is as an iatro-chemist that he claims a place in this work. His notions approach nearer to those of Paracelsus than to the hypotheses of Van Helmont and Sylvius. He admits the three chemical elements of Paracelsus, salt, sulphur, and mercury, in all the bodies in nature, and employs them to explain their properties and changes; but he gives the name of spirit to the mercury of Paracelsus. He ascribes to it the virtue of volatilizing all the constituent parts of bodies: salt, on the other hand, is the cause of fixity in bodies; sulphur produces colour and heat, and unites the spirit to the salt. In the stomach there occurs an acid ferment, which forms the chyle with the sulphur of the aliments: this chyle enters into effervescence in the heart, because the salt and sulphur take fire together. From this results the vital flame, which penetrates every thing. The vital spirits are secreted in the brain by a real distillation. The vessels of the testes draw an elixir from the constituent parts of the blood; but the spleen retains the earthy part, and communicates a new igneous ferment to the circulating fluid. On this account the blood must be considered as a humour, constantly disposed to fermentation, and in this respect it may be compared to wine. Every humour in which salt, sulphur, and spirit predominates in a certain manner, may be converted into a ferment. All diseases proceed from a morbid state or action of this ferment; and a physician may be compared to a wine-merchant; for, like him, he has nothing to do but to watch that the necessary fermentations take place with regularity, and that no foreign substance come to derange the operation.

At this period the mania of explaining every thing had proceeded to such a length, that no distinction was made between dead and living bodies. The chemical facts which were at that time known, were applied without hesitation to explain all the functions and all the diseases of the living body. According to Willis, fever is the simple result of a violent and preternatural effervescence of the blood and the other humours of the body, either produced by external causes, or by internal ferments, into which the chyle is converted when it mixes with the blood. The effervescence of the vital spirits is the source of quotidians; that of salt and sulphur produces continued fever; and external ferments of a malignant nature produce malignant fevers. Thus the smallpox is owing to the seeds of fermentation set in activity by an external principle of contagion. Spasms and convulsions are produced by an explosion of the salt and sulphur with the animal spirits. Hypochondriacal affections and hysteria depend originally on the morbid putrifaction of the blood in the spleen, or on a bad fermentescible principle, loaded with salt and sulphur, which unites with the vital spirits and deranges them. Scurvy is owing to an alteration of the blood, which may then be compared to vapid or stale wine. The gout is merely the coagulation of the nutritive juices altered by the acidified animal spirits; just as sulphuric acid forms a coagulum with carbonate of potash.

The action of medicines is easily explained by the effects which they produce on the nourishing principles. Sudorifics are considered as cordials, because they augment the sulphur of the blood, which is the true food of the vital flame. Cordials purify the animal spirits, and fix the too volatile blood. Willis disagrees with the other iatro-chemists of his time in one thing: he recommends bleeding in the greater number of diseases, as an excellent method of diminishing unnatural fermentation.

Dr. Croone, a celebrated Fellow of the Royal Society, was another English iatro-chemist, who attempted to explain muscular motion by the effervescence of the nervous fluid, or animal spirits.

It is not worth while to notice the host of writers—English, French, Italian, Dutch, and German, who exerted themselves to maintain, improve, and defend, the chemical doctrines of medicine. The first person who attempted to overturn these absurd doctrines, and to introduce something more satisfactory in their place, was Mr. Boyle, at that time in the height of his celebrity.

Robert Boyle was born at Youghall, in the province of Munster, on the 25th of January, 1627. He was the seventh son, and the fourteenth child of Richard, Earl of Cork. He was partly educated at home, and partly at Eton, where he was under the tuition of Sir Henry Wotton. At the age of eleven, he travelled with his brother and a French tutor through France to Geneva, where he pursued his studies for twenty-one months, and then went to Italy. During this period, he acquired the French and Italian languages; and, indeed, talked in the former with so much fluency and correctness, that he passed, when he thought proper, for a Frenchman. In 1642, his father’s finances were deranged, by the breaking out of the great Irish rebellion. His tutor, who was a Genevese, was obliged to borrow, on his own credit, a sum of money sufficient to carry him home. On his arrival, he found his father dead; and, though two estates had been left to him, such was the state of the times, that several years elapsed before he could command the requisite sum of money to supply his exigencies. He retired to an estate at Stalbridge, in Dorsetshire.

In 1654 he went to Oxford, where he associated himself with a number of eminent men (Dr. Willis among others), who had constituted themselves into a combination for experimental investigations, distinguished by the name of the Philosophical College. This society was transferred to London; and, in 1663, was incorporated by Charles II. under the name of the Royal Society. In 1668 Mr. Boyle took up his residence in London, where he continued till the last day of December, 1691, assiduously occupied in experimental investigations, on which day he died, in the sixty-fifth year of his age.

We are indebted to Mr. Boyle for the first introduction of the air-pump and the thermometer into Britain, and for contributing so much, by means of Dr. Hooke, to the improvement of both. His hydrostatical and pneumatical investigations and experiments constitute the foundation of these two sciences. The thermometer was first made an accurate instrument of investigation by Sir Isaac Newton, in 1701. This he did by selecting as two fixed points the temperatures at which water freezes and boils; marking these upon the stem of the thermometer, and dividing the interval between them into a certain number of degrees. All thermometers made in this way will stand at the same point when plunged into bodies of the same temperature. The number of divisions between the freezing and boiling points constitute the cause of the differences between different thermometers. In Fahrenheit’s thermometer, which is used in Great Britain, the number of degrees, between the freezing and boiling points of water, is 180; in Reaumur’s it is 80; in Celsius’s, or the centigrade, it is 100; and in De Lisle’s it is 150.

But my reason for mentioning Mr. Boyle here was, the attempt which he made in 1661, by the publication of his Sceptical Chemist, to overturn the absurd opinions of the iatro-chemists. He raises doubts, not only respecting the existence of the elements of the Peripatetics, but even of those of the chemists. The first elements of bodies, in his opinion, are atoms, of different shapes and sizes; the union of which gives origin to what we vulgarly call elements. We cannot restrain the number of these to four, as the Peripatetics do; nor to three, with the chemists: neither are they immutable, but convertible into each other. Fire is not the means that ought to be employed to obtain them; for the salt and sulphur are formed during its action by the union of different simple bodies.

Boyle shows, besides, that the chemical theory of qualities is exceedingly inaccurate and uncertain; because it takes for granted things which are very doubtful, and in many cases directly contrary to the phenomena of nature. He endeavours to prove the truth of these ideas, and particularly the production of the chemical principles, by a great number of convincing and conclusive experiments.

In another treatise, entitled “The Imperfections of the Chemical Doctrine of Qualities,”[169] he points out, in the second section, the insufficiency of the hypotheses of Sylvius relative to the generality of acids and alkalies. He shows that the offices ascribed to them are arbitrary, and the notions respecting them unsettled; that the hypotheses respecting them are needless, and insufficient, and afford but an unsatisfactory solution of the phenomena.

These arguments of Boyle did not immediately shake the credit of the chemical system. In the year 1691, a chemical academy was founded at Paris by Nicolas de Blegny, the express object of which was to examine these objections of Boyle, which by this time had attracted great attention. Boyle’s experiments were repeated and confirmed; but the academicians, notwithstanding, came to the conclusion, that it is unnecessary to have recourse to the true elements of bodies; and that the phenomena which occur in the animal economy may be explained by the predominance of acids or alkalies. Various other publications appeared, all on the same side.

In Germany, Hermann Conringius, the most skilful physician of his time, opposed the chemical theory; and his opinions were impugned by Olaus Borrichius, who defended not only alchymy, but the chemical theory of medicine, with equal erudition and zeal.[170]

Towards the end of the sixteenth century, the chemists thought of examining the liquids of the living body, to ascertain whether they really contained the acids and alkalies which had been assigned them, and considered as the cause of all diseases. But at that time chemistry had made so little progress, and such was the want of skill of those who undertook these investigations, that they readily obtained every thing that was wanted to confirm their previous notions. John Viridet, a physician of Geneva, announced that he had found an acid in the saliva and the pancreatic juice, and an alkali in the gastric juice and the bile. But the most celebrated experiments of that period were those of Raimond Vieussens, undertaken in 1698, in order to discover the presence of an acid spirit in the blood. His method was, to mix blood with a species of clay, called bole, and to subject the mixture to distillation. He found that the liquid distilled over was acid. Charmed with this discovery, which he considered as of first-rate importance, he announced it by letter to the different academies and colleges in Europe. Some doubts being raised about the accuracy of his experiment, it having been alleged that the acid came from the clay which he had mixed with the blood, and not from the blood itself, Vieussens purified the bole from all the acid which it could contain, and repeated his experiment again. The result was the same—the acrid salt of the fluid yielded an acid spirit.

It would be needless in the present state of our knowledge to point out the inaccuracy of such an experiment, or how little it contributed to prove that blood contains a free acid. It is now well known to chemists, that blood is remarkably free from acids; and, that if we except a little common salt, which exists in all the liquids of the human body, there is neither any acid nor salt whatever in that liquid.

Michael Ettmuller, at Leipsic, who was a chemist of some eminence in his day, and published a small treatise on the science, which was much sought after, was also a zealous iatro-chemist; but his opinions were obviously regulated by the researches of Boyle. He denies the existence of acids and alkalies in certain bodies, and distinguishes carefully between acid and putrid fermentation.

One of the most formidable antagonists to the iatro-chemical doctrines was Dr. Archibald Pitcairne, first a professor of medicine in the University of Leyden, and afterwards of Edinburgh, and one of the most eminent physicians of his time. He was born in Edinburgh, on the 25th of December, 1652. After finishing his school education in Dalkeith, he went to the University of Edinburgh, where he improved himself in classical learning, and completed a regular course of philosophy. He turned his attention to the law, and prosecuted his studies with so much ardour and intensity that his health began to suffer. He was advised to travel, and set out accordingly for the South of France: by the time he reached Paris he was so far recovered that he determined to renew his studies; but as there was no eminent professor of law in that city, and as several gentlemen of his acquaintance were engaged in the study of medicine, he went with them to the lectures and hospitals, and employed himself in this way for several months, till his affairs called him home.

On his return he applied himself chiefly to mathematics, in which, under the auspices of his friend, the celebrated Dr. David Gregory, he made uncommon progress. Struck with the charms of this science, and hoping by the application of it to medicine to reduce the healing art under the rigid rules of mathematical demonstration, he formed the resolution of devoting himself to the study of medicine. There was at that time no medical school in Edinburgh, and no hospital at which he could improve himself; he therefore repaired to Paris, and devoted himself to his studies with a degree of ardour that ensured an almost unparalleled success. In 1680 he received from the faculty of Rheims the degree of doctor of medicine, a degree also conferred on him in 1699 by the University of Aberdeen.

In the year 1691 his reputation was so high that the University of Leyden solicited him to fill the medical chair, at that time vacant; he accepted the invitation, and delivered a course of lectures at Leyden, which was greatly admired by all his auditors, among whom were Boerhaave and Mead. At the close of the session he set out for Scotland, to marry the daughter of Sir Archibald Stevenson: his friends in his own country would not consent to part with him, and thus he was reluctantly obliged to resign his chair in the University of Leyden.

He settled as a physician in Edinburgh, where he was appointed titular professor of medicine. His practice extended beyond example, and he was more consulted by foreigners than any Edinburgh physician either before or after his time. He died in October, 1713, admired and regretted by the whole country. He was a zealous supporter of iatro-mathematics, and as such a professed antagonist of the iatro-chemists. He refuted their opinions with much strength of reasoning, while his high reputation gave his opinions an uncommon effect; so that he contributed perhaps as much as any one, to put a period to the most disgraceful, as well as dangerous, set of opinions that ever overspread the medical horizon.

Into the merits of the iatro-mathematicians it is not the business of this work to enter; they at least display science, and labour, and erudition, and in all these respects are far before the iatro-chemists. Perhaps their own opinions were not more agreeable to the real structure of the human body, nor their practice more conformable to reason, or more successful than those of the chemists. Probably the most valuable of all Dr. Pitcairne’s writings, is his vindication of the claims of Hervey to the great discovery of the circulation.

Boerhaave, the pupil of Pitcairne, and afterwards a professor in Leyden, was a no less zealous or successful opponent of the iatro-chemists.

Herman Boerhaave, perhaps the most celebrated physician that ever existed, if we except Hippocrates, was born at Voorhout, a village near Leyden, in 1668, where his father was the parish clergyman. At the age of sixteen he was left without parents, protection, advice, or fortune. He had already studied theology, and the other branches of knowledge that are considered as requisite for a clergyman, to which situation he aspired; and while occupied with these studies he supported himself at Leyden by teaching mathematics to the students—a branch of knowledge to which he had devoted himself with considerable ardour while living in his father’s house. But, a report being raised that he was attached to the doctrines of Spinoza, the clamour against him was so loud that he thought it requisite to renounce his intention of going into orders.[171] He turned his studies to medicine, and the branches of science connected with that pursuit, and these delightful subjects soon engrossed the whole of his attention. In 1693 he was created doctor of medicine, and began to practise. He continued to teach mathematics for some time, till his practice increased sufficiently to enable him to live by his fees. His spare money was chiefly laid out upon books; he also erected a chemical laboratory, and though he had no garden he paid great attention to the study of plants. His reputation increased with considerable rapidity; but his fortune rather slowly. He was invited to the Hague by a nobleman, who stood high in the favour of William III., King of Great Britain; but he declined the invitation. His three great friends, to whom he was in some measure indebted for his success, were James Trigland, professor of theology, Daniel Alphen, and John Van den Berg, both of them successively chief magistrates of Leyden, and men of great influence.

Van den Berg recommended him to the situation of professor of medicine in the University of Leyden, to which chair he was raised, fortunately for the reputation of the university, on the death of Drelincourt, in 1702. He not only gave public lectures on medicine, but was in the habit also of giving private instructions to his pupils. His success as a teacher was so great, that a report having been spread of his intention to quit Leyden, the curators of the university added considerably to his salary on condition that he would not leave them.

This first step towards fortune and eminence having been made, others followed with great rapidity. He was appointed successively professor of botany and of chemistry, while rectorships and deanships were showered upon him with an unsparing hand. And such was the activity, the zeal, and the ability with which he filled all these chairs, that he raised the University of Leyden to the very highest rank of all the universities of Europe. Students flocked to him from all quarters—every country of Europe furnished him with pupils; Leyden was filled and enriched by an unusual crowd of strangers. Though his class-rooms were large, yet so great was the number of students, that it was customary for them to keep places, just as is done in a theatre when a first-rate actor is expected to perform. He died in the year 1738, while still filling the three different chairs with undiminished reputation.

It is not our object here to speak of Boerhaave as a physician, or as a teacher of medicine, or of botany; though in all these capacities he is entitled to the very highest eulogium; his practice was as unexampled as his success as a teacher. It is solely as a chemist that he claims our attention here. His system of chemistry, published in two quarto volumes in 1732, and of which we have an excellent English translation by Dr. Shaw, printed in 1741, was undoubtedly the most learned and most luminous treatise on chemistry that the world had yet seen; it is nothing less than a complete collection of all the chemical facts and processes which were known in Boerhaave’s time, collected from a thousand different sources, and from writings equally disgusting from their obscurity and their mysticism. Every thing is stated in the plainest way, stripped of all mystery, and chemistry is shown as a science and an art of the first importance, not merely to medicine, but to mankind in general. The processes given by him are too numerous and too tedious to have been all repeated by one man, how laborious soever he may have been: many of them have been taken upon trust, and, as no distinction is made in the book, between those which are stated upon his own authority and those which are merely copied from others, this treatise has been accused, and with some justice, as not always to be depended on. But the real information which it communicates is prodigious, and when we compare it with any other system of chemistry that preceded it, the superiority of Boerhaave’s information will appear in a very conspicuous point of view.

After a short but valuable historical introduction he divides his work into two parts; the first treats of the theory of chemistry, the second of the practical processes.

He defines chemistry as follows: “Chemistry is an art which teaches the manner of performing certain physical operations, whereby bodies cognizable to the senses, or capable of being rendered cognizable, and of being contained in vessels, are so changed by means of proper instruments, as to produce certain determinate effects; and at the same time discover the causes thereof; for the service of various arts.”

This definition is not calculated to throw much light on chemistry to those who are unacquainted with its nature and object. Neither is it conformable to the modern notions entertained of chemistry; but it is requisite to keep in mind Boerhaave’s definition of chemistry, when we examine his system, that we may not accuse him of omissions and imperfections, which are owing merely to the state of the science when he gave his system to the world.

In his theory of chemistry he begins with the metals, which he treats of in the following order: Gold, mercury, lead, silver, copper, iron, tin. The account of them, though imperfect, is much fuller and more satisfactory than any that preceded it. He then treats of the salts, which are, common salt, saltpetre, borax, sal ammoniac and alum. This it will be admitted is but a meagre list. However other salts occur in different parts of the book which are not described here. He next gives an account of sulphur. Here he introduces white arsenic, obtained, he says, from cobalt, and not known for more than two hundred years. He considers it as a real sulphur, and takes no notice of metallic arsenic, though it had been already alluded to by Paracelsus. He then treats of bitumens, including under the name not merely bitumens liquid and solid, but likewise pit-coal, amber, and ambergris. An account of stones and earths comes next, and constitutes the most defective part of the book. It is very surprising that in this part of his work he takes no notice of lime. The semi-metals come next: they are, antimony, bismuth, zinc. Here he gives an account of the three vitriols or sulphates of iron, copper, and zinc. He knew the composition of sulphate of iron; but was ignorant of that of sulphate of copper and sulphate of zinc. He considers semi-metals as compounds of a true metal and sulphur, and therefore enumerates cinnabar among the semi-metals. Lastly he treats of vegetables and animals; and it is needless to say that his account is very imperfect.

He next treats of the utility of chemistry, and shows its importance in natural philosophy, medicine, and the arts. Afterwards he describes the instruments of chemistry. This constitutes the longest and the most important part of the whole work. He first treats of fire at great length. Here we have an account of the thermometer, of the expansion produced by heat, of steam, and in fact the germ of many of the most important parts of the science of heat, which have since been expanded and applied to the improvement, not merely of chemistry, but of the arts and resources of human industry. The experiments of Fahrenheit related by him, on the change of temperature induced by agitating water and mercury together at different degrees of heat, gave origin to the whole doctrine of specific heats. Though Boerhaave himself seemed not aware of the importance of these experiments, or indeed even to have considered them with any attention. But when afterwards analyzed by Dr. Black, these experiments gave origin to one of the most important parts of the whole science of heat.

He next treats at great length on fuel. Here his opinions are often very erroneous, from his ignorance of a vast number of facts which have since come to light. It is curious that during the whole of his very long account of combustion he makes no allusion to the peculiar opinions of Stahl on the subject; though they were known to the public, and had been admitted by chemists in general, before his work was published. To what are we to ascribe this omission? It could scarcely have been owing to ignorance, Stahl’s reputation being too high to allow his opinions to be treated with neglect. We must suppose, I think, that Boerhaave did not adopt Stahl’s doctrine of combustion; but at the same time did not think it proper to enter into any controversy on the subject.

He next treats of the heat produced when different liquids are mixed, as alcohol and water, &c. He gives many examples of such increase of temperature, and describes the phenomena very correctly. But he was unable to assign the cause of the evolution of this heat. The subject was elucidated many years after by Dr. Irvine, who showed that it was owing to a diminution of the specific heat which takes place when liquids combine chemically together. It is in this part of his work that he gives an account of phosphorus, of the action of nitric acid on volatile oils, and he concludes, from all the facts which he states, that elementary fire is a corporeal body. His explanation of the combustion of Homberg’s pyrophorus and of common phosphorus, shows clearly that he had no correct notion of the reason why air is necessary to maintain combustion, nor of the way in which that elastic fluid performs its part in the great phenomena of nature.

He next treats of the mode of regulating fire for chemical purposes: then he treats of air, his account being chiefly taken from Boyle. He ascribes the discovery of the law of the elasticity of air both to Boyle and Mariotte. Boyle, I believe, was the first discoverer of it. The French are in the habit of calling it the law of Mariotte. He then treats of water, and lastly of earth; but even here no mention whatever is made of lime. In the last part of the theory of chemistry he treats at great length of menstruums. These are water, oils, alcohol, alkalies, acids, and neutral salts. He mentions potash and ammonia, but takes no notice of soda; the difference between potash and soda not being accurately known. Nor can we expect any particular account of the difference between the properties of mild and caustic potash; as this subject was not understood till the time of Dr. Black. The only acids which he mentions are the acetic, sulphuric, nitric, muriatic, and aqua regia. He subjoins a disquisition on the alcahest or universal solvent, which it is obvious enough, however, from the way in which he speaks of it, that he was not a believer in. The object of his practical part is to teach the method of making all the different chemical substances known when he wrote. This he does in two hundred and twenty-seven processes, in which all the manipulations are described with considerable minuteness. This part of the work must have been long considered as of great utility, and must have been long resorted to by the student as a mine of practical information upon almost every subject that could arrest his attention. So immense is the progress that chemistry has made since the days of Boerhaave, and so different are the researches that at present occupy chemists, and so much greater the degree of precision requisite to be attained, that his processes and directions are now of little or no use to a practical student of chemistry, as they convey little or none of the knowledge which it is requisite for him to possess.

Boerhaave made a set of most elaborate experiments, to refute the ideas of the alchymists respecting the possibility of fixing mercury. He put a quantity of pure mercury into a glass vessel, and kept it for fifteen years at a temperature rather higher than 100°. It underwent no alteration whatever, excepting that a small portion of it was converted into a black powder. But this black powder was restored to the state of running mercury by trituration in a mortar. In this experiment the air had free access to the mercury. It was repeated in a close vessel with the same result, excepting that the mercury was kept hot for only six months instead of fifteen years.

To show that mercury cannot be obtained from metals by the processes recommended by the alchymists, he dissolved pure nitrate of lead in water, and, mixing the solution with sal ammoniac, chloride of lead precipitated. Of this chloride he put a quantity into a retort, and poured over it a strong lixivium of caustic potash, The whole was digested at the temperature of 96° for six months and six days. It was then distilled in a glass retort, by a temperature gradually raised to redness, but not a particle of mercury was evaporated, as it had been alleged by the alchymists would be the case.

Isaac Hollandus had stated that mercury could be easily obtained from the salt of lead made by means of distilled vinegar. To prove this he calcined a quantity of acetate of lead, ground the residue to powder, and triturated it with a very strong alkaline lixivium, and kept the lixivium over it covered with paper for months, taking care to add water in proportion as it evaporated. The calx was then distilled in a heat gradually raised to redness; but not a particle of mercury was obtained.[172]

These were not the only laborious experiments which he made with this metal. He distilled it above five hundred times, and found that it underwent no alteration. When long agitated in a glass bottle it is convertible into a black acrid powder, obviously protoxide of mercury. This black powder, when distilled, is converted into running mercury. Exposure of mercury for some months in a heat of 180°, converts it also into protoxide; and if the heat be higher than this, the mercury is converted into a red acrid substance, obviously peroxide of mercury. But this peroxide, by simple distillation, is again reduced into the state of running mercury.[173]

Boerhaave combated the opinions of the iatro-chemists with great eloquence, and with a weight derived from his high reputation, and the extraordinary veneration in which his opinions were held by his disciples. His efforts were assisted by those of Bohn, who combated the medical opinions by arguments drawn both from experience and observation, and perfectly irresistible; and the ruin of the chemical sect was consummated by the exertions of the celebrated Frederick Hoffmann, the founder of the most perfect and satisfactory system of medicine that has ever appeared. His efforts were probably roused into action by a visit which he paid to England in 1683, during which he got acquainted with Boyle and with Sydenham; the former the greatest experimentalist, and the latter the greatest physician of the time; and both of whom were declared enemies to iatro-chemistry.

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CHAPTER VI.
OF AGRICOLA AND METALLURGY.

I have been induced by a wish to prosecute the history of the opinions first supported by Paracelsus, and carried so much further by Van Helmont and Sylvius, to give a connected view of their effects upon medical practice and medical theory; and I have come to the commencement of the eighteenth century, without taking notice of one of the most extraordinary men, and one of the greatest promoters of chemistry that ever existed: I mean George Agricola. I shall consecrate the whole of this chapter to his labours, and those of his immediate successors.

George Agricola was born at Glaucha, in Misnia, in the year 1494. When a young man he acquired such a passion for mining and minerals, by frequenting the mountains of Bohemia, that he could not be persuaded to relinquish the study. He settled, indeed, as a physician, at Joachimstal; but his favourite study engrossed so much of his attention, that he succeeded but ill in his medical capacity. This induced him to withdraw to Chemnitz, where he devoted himself to his favourite pursuits. He studied the mineralogical writings of the ancients with the most minute accuracy; but not satisfied with this, he visited the mines in person, examined the processes followed by the miners in extracting the different ores, and in washing and sorting them. He made collections of all the different ores, and studied their nature and properties attentively: he likewise collected information about the methods of smelting them, and extracting from them the metals in a state of purity. The information which he collected, respecting the mines wrought in the different countries of Europe, is quite wonderful, if we consider the period in which he lived, the little intercourse which existed between nations, and the total want of all those newspapers and journals which now carry every new scientific fact with such rapidity to every part of the world.

Agricola died at Chemnitz in the year 1555, after he had reached the sixty-first year of his age. Maurice, the celebrated Elector of Saxony, settled on him a pension, the whole of which he devoted to his metallurgic pursuits. To him we find him dedicating the edition of his works which he published in the year of his death, and which is dated the fourteenth before the calends of April, 1555. He even spent a considerable proportion of his own estate in following out his favourite investigations. In the earlier part of his life he had expressed himself rather favourable to the protestant opinions; but in his latter days he had attacked the reformed religion. This rendered him so odious to the Lutherans, at that time predominant in Chemnitz, that they suffered his body to remain unburied for five days together; so that it was necessary to remove it from Chemnitz to Zeitz, where it was interred in the principal church.

His great work is his treatise De Re Metallica, in twelve books. In this work he gives an account of the instruments and machines, and every thing connected with mining and metallurgy; and even gives figures of all the different pieces of apparatus employed in his time. He has also exhibited the Latin and German names for all these different utensils. This work may be considered as a very complete treatise on metallurgy, as it existed in the sixteenth century. The first six books are occupied with an account of mining and smelting. In the seventh book he treats of docimasy, or the method of determining the quantity of metal which can be extracted from every particular ore. This he does so completely, that most of his processes are still followed by miners and smelters. He gives a minute and accurate account of the furnaces, muffles, crucibles, &c., almost such as are still employed, with minute directions for preparing the ores which are to be subjected to examination, the fluxes with which they must be mixed, and the precautions necessary in order to obtain a satisfactory result. In short, this book may be considered as a complete manual of docimasy. How much of the methods given originated with Agricola it is impossible to say. He probably did little more than collect the scattered processes employed by the smelters of metals, in different parts of the world, and reduce the whole to a regular system. But this was a great deal. Perhaps it is not saying too much, that the great progress made in the chemical investigation of the metals, was owing in a great measure to the labours of Agricola. Certainly the progress made by the moderns, in the difficult arts of mining and metallurgy, must in a great measure be ascribed to the labours of Agricola.

In the eighth book he describes the mechanical preparation of the ores, and the mode of roasting them, either in the open air or in furnaces. The ninth book is occupied with an account of smelting-furnaces. It contains also a description of the processes for obtaining mercury, antimony, and bismuth, from their ores. The tenth book treats of the separation of silver and gold from each other, by means of nitric acid and aqua regia: minute directions for the preparation of which are given. The modes of purifying the precious metals by means of sulphur, antimony, and cementations, are also described. In the eleventh book he treats of the method of purifying silver from copper and iron, by means of lead. He gives an account also of the processes employed for smelting and purifying copper. In the twelfth book he treats of the methods of preparing common salt, saltpetre, alum, and green vitriol, or sulphate of iron: of the preparation and purification of sulphur, and of the mode of manufacturing glass. In short, Agricola’s work De Re Metallica is beyond comparison the most valuable chemical work which the sixteenth century produced, and places the author very high indeed among the list of the improvers of chemistry.

The other works of Agricola are his treatise De Natura Fossilium, in ten books; De Ortu et Causis Subterraneorum, in five books; De Natura eorum quæ effluunt ex Terra, in four books; De veteribus et novis Metallis, in two books; and his Bermannus sive de re metallica Dialogus. The treatise De veteribus et novis Metallis is amusing. He not only collects together all the historical facts on record, respecting the first discoverers of the different metals and the first workers of mines, but he gives many amusing anecdotes nowhere else to be found, respecting the way in which some of the most celebrated German mines were discovered. In the second book he takes a geographical view of every part of the known world, and states the mines wrought and the metals found in each. We must not suppose that all his statements in this historical sketch are accurate: to admit it would be to allow him a greater share of information than could possibly belong to any one man. He frequently gives us the authority upon which his statements are founded; but he often makes statements without any authority whatever. Thus he says, that a mine of quicksilver had been recently discovered in Scotland: the fact however, is, that no quicksilver-mine ever existed in any part of Britain. There was, indeed, a foolish story circulated about thirty years ago, about a vein of quicksilver found under the town of Berwick-upon-Tweed; but it was an assertion unsupported by any authentic evidence.

Many years elapsed before much addition was made to the processes described by Agricola. In the year 1566, Pedro Fernandes de Velasco introduced a method of extracting gold and silver from their ores in Mexico and Peru by means of quicksilver. But I have never seen a description of his process. Alonzo Barba claims for himself, and seemingly with justice, the method of amalgamating the ores of gold and silver by boiling. Barba was a Spanish priest, who lived about the year 1609, at Tarabuco, a market-town in the province of Charcso, eight miles from Plata, in South America. In the year 1615 he was curate at Tiaguacano, in the Province of Pacayes, and in 1617, he lived at Lepas in Peru. He is said to have been a native of Lepe, a small township in Andalusia, and had for many years the living of the church of St. Bernard at Potosi. His work on the amalgamation of gold and silver ores appeared at Madrid in the year 1640, in quarto.[174] In the year 1629 a new edition of it appeared with an appendix, under the title of “Trattado de las Antiquas Minas de España de Alonzo Carillo Lasso.” The English minister at the Court of Madrid, the Earl of Sandwich, published the first part of it in an English translation at London, in 1674, under the title of “The First Book of the Art of Metals, in which is declared the manner of their generation, and the concomitants of them, written in Spanish by Albaro Alonzo Barba. By E. Earl of Sandwich.”

The next improver of metallurgic processes was Lazarus Erckern, who was upper bar-master at Kuttenberg, in the year 1588, and was superintendent of the mines in Germany, Hungary, Transylvania, the Tyrol, &c., to three successive emperors. His work has been translated into English under the title of “Heta Minor; or the laws of art and nature in knowing, judging, assaying, fining, refining, and enlarging the bodies of confined metals. To which are added essays on metallic words, illustrated with sculptures. By Sir J. Pettus. London, 1683, folio.” But this translation is a very bad one. Erckern gives a plain account of all the processes employed in his time without a word of theory or reasoning. It is an excellent practical book; though it is obvious enough that the author was inferior in point of abilities to Agricola. His treatment of Don Juan de Corduba, who offered, in 1588, to put the Court of Vienna in possession of the Spanish method of extracting gold and silver from the ores by amalgamation, as related by Baron Born in his work on amalgamation, shows very clearly that Erckern was a very illiberal-minded man, and puffed up with an undue conceit of his own superior knowledge.[175] Had he condescended to assist the Spaniard, and to furnish him with proper materials to work upon, the Austrians might have been in possession of the process of amalgamation with all its advantages a couple of centuries before its actual introduction.

I need not take any notice of the docimastic treatises of Schindlers and Schlutter, which are of a much later date, and both of which have been translated into French, the former by Geoffroy, junior; the latter by Hellot. This last translation, in two large quartos, published in 1764, constitutes a very valuable book, and exhibits all the docimastic and metallurgic processes known at that period with much fidelity and minuteness. Very great improvements have taken place since that period, but I am not aware of any work published in any of the European languages, that is calculated to give us an exact idea of the present state of the various mining and metallurgic processes—important as they are to civilized society.

Gellert’s Metallurgic Chemistry, so far as it goes, is an excellent book.

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CHAPTER VII.
OF GLAUBER, LEMERY, AND SOME OTHER CHEMISTS OF THE END OF THE SEVENTEENTH CENTURY.

Hitherto I have treated of the alchymists, or iatro-chemists, and have brought the history of chemistry down to the beginning of the eighteenth century. But during the seventeenth century there existed several laborious chemists, who contributed very materially by their exertions, either to extend the bounds of the science, or to increase its popularity and respectability in the eyes of the world. Of some of the most eminent of these it is my intention to give an account in this chapter.

Of John Rudolf Glauber, the first of these meritorious men in point of time, I know very few particulars. He was a German and a medical man, and spent most of his time at Salzburg, Ritzingen, Frankfort on the Maine, and at Cologne. Towards the end of his life he went to Holland, but during the greatest part of his residence in that country he was confined to a sick-bed. He died at Amsterdam in 1668, after having reached a very advanced age. Like Paracelsus, whom he held in high estimation, he was in open hostility with the Galenical physicians of his time. This led him into various controversies, and induced him to publish various apologies; most of which still remain among his writings. One of the most curious of these apologies is the one against Farmer. To this man Glauber had communicated certain secrets of his own, which were at that time considered as of great value; Farrner binding himself not to communicate them to any person. This obligation he not only broke, but publicly deprecated the skill and integrity of Glauber, and offered to communicate to others, for stipulated sums, a set of secrets of his own, which he vaunted of as particularly valuable. Glauber examines these secrets, and shows that every one of them possessed of any value, had been communicated by himself to Farrner, and to put an end to Farrner’s unfair attempt to make money by selling Glauber’s secrets, he in this apology communicates the whole processes to the public.

Glauber’s works were published in Amsterdam, partly in Latin, and partly in the German language. In the year 1689 an English translation of them was published in London by Mr. Christopher Packe, in one large folio volume. Glauber was an alchymist and a believer in the universal medicine. But he did not confine his researches to these two particulars, but endeavoured to improve medicine and the arts by the application of chemical processes to them. In his treatise of philosophical furnaces he does not confine himself to a description of the method of constructing furnaces, and explaining the use of them, but gives an account of a vast many processes, and medicinal and chemical preparations, which he made by means of these furnaces. One of the most important of these preparations was muriatic acid, which he obtained by distilling a mixture of common salt, sulphate of iron, and alum, in one of the furnaces which he describes.

He makes known the method of dissolving most of the metals in muriatic acid, and the resulting chlorides, which he denominates oils of the respective metals, constitute in his opinion valuable medicines. He mentions particularly the chloride of gold, and from the mode of preparing it, the solution must have been strong. Yet he recommends it as an internal medicine, which he says may be taken with safety, and is a sovereign remedy in old ulcers of the mouth, tongue, and throat, arising from the French pox, leprosy, scorbute, &c. Thus we see the use of gold as a remedy for the venereal disease did not originate with M. Chretiens, of Montpelier. This chloride of gold is so violent a poison that it is remarkable that Glauber does not specify the dose that patients labouring under the diseases for which he recommends it ought to take.—The sesqui-chloride of iron he recommends as a most excellent application to ill-conditioned ulcers and cancers. We see from this that the use of iron in cancers, lately recommended, is not so new a remedy as has been supposed.

He mentions the violent action of chloride of mercury (obviously corrosive sublimate), and says that he saw a woman suddenly killed by it, being administered internally by a surgeon. Butter of antimony he first recognised as nothing else than a combination of chlorine and antimony; before his time it had been always supposed to contain mercury.

He describes the method of obtaining sulphuric acid by distilling sulphate of iron; gives an account of the mode of obtaining sulphate of iron and sulphate of copper, in crystals: the method of obtaining nitric acid from nitre by means of alum, was much improved by him. He gives a particular detail of the way of obtaining fulminating gold. This fulminating gold he says is of little use in medicine; but he gives a method of preparing from it a red tincture of gold, which he considers as one of the most useful and efficacious of all medicines: this tincture is nothing else than chloride of gold. It would take up too much space to attempt an analysis of all the curious facts and preparations described in this treatise on philosophical furnaces; but it will repay the perusal of any person who will take the trouble to look into it. All the different pharmacopœias of the seventeenth century borrowed from it largely. The third part of this treatise is peculiarly interesting. It will be seen that Glauber had already thought of the peculiar efficacy of applying solutions of sulphur, &c. to the skin, and had anticipated the various vapour and gaseous baths which have been introduced in Vienna and other places, during the course of the present century, and considered as new, and as constituting an important era in the healing art. In the fourth part he not only treats of the docimastic processes, so well described by Agricola and Erckern, but gives us the method of making glass, and of imitating the precious stones by means of coloured glasses. The fifth part is peculiarly valuable; in it he treats of the methods of preparing lutes for glass vessels, of the construction and qualities of crucibles, and of the vitrification of earthen vessels.

Another of his tracts is called “The Mineral Work;” the object of which is to show the method of separating gold from flints, sand, clay, and other minerals, by the spirit of salt (muriatic acid), which otherwise cannot be purged; also a panacea, or universal antimonial medicine. This panacea was a solution of deutoxide of antimony in pyrotartaric acid; Glauber gives a most flattering account of its efficacy in removing the most virulent diseases, particularly all kinds of cutaneous eruptions. The second and third parts of The Mineral Work are entirely alchymistical. In the treatise called “Miraculum Mundi,” his chief object is to write a panegyric on sulphate of soda, of which he was the discoverer, and to which he gave the name of sal mirabile. The high terms in which he speaks of this innocent salt are highly amusing, and serve well to show the spirit of the age, and the dreams which still continued to haunt the most laborious and sober-minded chemists. The sal mirabile was not merely a purgative, a virtue which it certainly possesses in a high degree, being as mild a purgative, perhaps the very best, of all the saline preparations yet tried; but it was a universal medicine, a panacea, a cure for all diseases: nor was Glauber contented with this, but pointed out many uses in the various arts and manufactures for which in his opinion it was admirably fitted. But by far the fullest account of this sal mirabile is given by him in his treatise on the nature of salts.

I shall satisfy myself with giving the titles of his other tracts. Every one of them contains facts of considerable importance, not to be found in any chemical writings that preceded him; but to attempt to connect these facts into one point of view would be needless, because they are not such as would be likely to interest the general reader.

1. The Consolation of Navigators. This gives an account of a method by which sailors may carry with them a great deal of nourishment in very small bulk. The method consists in evaporating the wort of malt to dryness, and carrying the dry extract to sea. This method has been had recourse to in modern times, and has been found to furnish an effectual remedy against the scurvy. He recommends also the use of muriatic acid as a remedy for thirst, and a cure for the scurvy.

2. A true and perfect Description of the extracting good Tartar from the Lees of Wine.

3. The first part of the Prosperity of Germany; in which is treated of the concentration of wine, corn, and wood, and the more profitable use of them than has hitherto been.

4. The second part of the Prosperity of Germany; wherein is shown by what means minerals may be concentrated by nitre, and turned into metallic and better bodies.

5. The third part of the Prosperity of Germany; in which is delivered the way of most easily and plentifully extracting saltpetre out of various subjects, every where obvious and at hand. Together with a succinct explanation of Paracelsus’s prophecy; that is to say, in what manner it is to be understood the northern lion will institute or plant his political or civil monarchy; and that Paracelsus himself will not abide in his grave; and that a vast quantity of riches will offer itself. Likewise who the artist Elias is, of whose coming in the last days, and his disclosing abundance of secrets, Paracelsus and others have predicted.

6. The fourth part of the Prosperity of Germany; in which are revealed many excellent, useful secrets, and such as are serviceable to the country; and withal several preparations of efficacious cates extracted out of the metals and appointed to physical uses; as also various confections of golden potions. To which is also adjoined a small treatise which maketh mention of my laboratory; in which there shall be taught and demonstrated (for the public good and benefit of mankind) wonderful secrets, and unto every body most profitable but hitherto unknown.

7. The fifth part of the Prosperity of Germany; clearly and solidly demonstrating and as it were showing with the fingers, what alchymy is, and what benefit may, by the help thereof, be gotten every where and in most places of Germany. Written and published to the honour of God, the giver of all good things, primarily; and to the honour of all the great ones of the country; and for the health, profit, and assistance against foreign invasions, of all their inhabitants that are by due right and obedience subject unto them.

8. The sixth and last part of the Prosperity of Germany; in which the arcanas already revealed in the fifth part, are not only illustrated and with a clear elucidation, but also such are manifested as are most highly necessary to be known for the defence of the country against the Turks. Together with an evident demonstration adjoined, showing, that both a particular and universal transmutation of the imperfect metals into more perfect ones by salt and fire, is most true; and withal, by what means any one, that is endued with but a mean knowledge in managing the fire, may experimentally try the truth hereof in twenty-four hours’ space.

9. The first century of Glauber’s wealthy Storehouse of Treasures.—Many of the processes given in this treatise are mystically stated, or even concealed.

10. The second, third, fourth, and fifth century of Glauber’s wealthy Storehouse of Treasures.

11. New chemical Light; being a revelation of a certain new invented secret, never before manifested to the world.—This was a method of extracting gold from stones. Probably the gold found by Glauber in his processes existed in some of the reagents employed; this, at least, is the most natural way of accounting for the result of Glauber’s trials.

15. The spagyrical Pharmacopœia, or Dispensatory.—In this book he treats chiefly of medicines peculiarly his own; one of those, on which he bestows the greatest praise, is secret sal ammoniac, or sulphate of ammonia. He describes the method of preparing this salt, by saturating sulphuric acid with ammonia. He informs us that it was much employed by Paracelsus and Van Helmont, who distinguished it by the name of alkahest.

13. Book of Fires.—Full of enigmas.

14. Treatise of the three Principles of Metals; viz. sulphur, mercury, and salt of philosophers; how they may be profitably used in medicine, alchymy, and other arts.

15. A short Book of Dialogues. Chiefly relating to alchymy.

16. Proserpine, or the Goddess of Riches.

17. Of Elias the Artist.

18. Of the three most noble Stones generated by three Fires.

19. Of the Purgatory of Philosophers.

20. Of the secret Fire of Philosophers.

21. A Treatise concerning the Animal Stone.

John Kunkel, who acquired a high reputation as a chemist, was born in the Duchy of Sleswick; in the year 1630: his father was a trading chemist, or apothecary; and Kunkel himself had, in his younger years, paid great attention to the business of an apothecary: he had also diligently studied the different processes of glass-making; and had paid particular attention to the assaying of metals. In the year 1659, he was chamberlain, chemist, and superintendent of apothecaries to the dukes Francis Charles and Julius Henry, of Lauenburg. While in this situation, he examined many pretended transmutations of metals, and undertook other researches of importance. From this situation he was invited, by John George II., Elector of Saxony, on the recommendation of Dr. Langelott and Counsellor Vogt, as chamberlain and superintendent of the elector’s laboratory, with a considerable salary. From this situation he went to Berlin, where he was chemist to the elector Frederick William; after whose death, his laboratory and glass-house were accidentally burnt. From Berlin he was invited to Stockholm by Charles XI., King of Sweden, who gave him the title of counsellor of metals, and raised him to the rank of a nobleman: here he died, in 1702, in the seventy-second year of his age. Kunkel’s greatest discovery was, the method of extracting phosphorus from urine. This curious substance had been originally discovered by Brandt, a chemist, of Hamburg, in the year 1669, as he was attempting to extract from human urine a liquid capable of converting silver into gold. He showed a specimen of it to Kunkel, with whom he was acquainted: Kunkel mentioned the fact as a piece of news to one Kraft, a friend of his in Dresden, where he then resided: Kraft immediately repaired to Hamburg, and purchased the secret from Brandt for 200 rix-dollars, doubtless exacting from him, at the same time, a promise not to reveal it to any other person. Soon after, he exhibited the phosphorus publicly in Britain and in France; whether for money, or not, does not appear. Kunkel, who had mentioned to his friend his intention of getting possession of the process, being vexed at the treacherous conduct of Kraft, attempted to discover it himself, and, after three or four years labour, he succeeded, though all that he knew from Brandt was, that urine was the substance from which the phosphorus was procured. In consequence of this success, phosphorus was at first distinguished by the epithet of Kunkel added to the name.

Kunkel published, in 1678, a treatise on phosphorus, in which he describes the properties of this substance, at that time a subject of great wonder and curiosity. In this treatise, he proposes phosphorus as a remedy of some efficacy, and gives a formula for preparing pills of it, to be taken internally. It is therefore erroneous to suppose, as has been done, that the introduction of this dangerous remedy into medicine is a modern discovery. Kunkel appears to have been acquainted with nitric ether. One of the most valuable of his books, is his treatise on glass-making, which was translated into French; and which, till nearly the end of the eighteenth century, constituted by far the best account of glass-making in existence. The following is a list of the most important of his works:

1. Observations on fixed and volatile Salts, potable Gold and Silver, Spiritus Mundi, &c.; also of the colour and smell of metals, minerals, and bitumens.—This tract was published at Hamburg, in 1678, and has been several times reprinted since.

2. Chemical Remarks on the chemical Principles, acid, fixed and volatile alkaline Salts, in the three kingdoms of nature, the mineral, vegetable, and animal; likewise concerning their colour and smell, &c.; with a chemical appendix against non-entia chymica.

3. Treatise of the Phosphorus mirabilis, and its wonderful shining Pills; together with a discourse on what was formerly rightly named nitre, but is now called the blood of nature.

4. An Epistle against Spirit of Wine without an acid.

5. Touchstone de Acido et Urinoso, Sale calido et frigido.

6. Ars Vitraria experimentalis.

7. Collegium Physico-chymicum experimentale, or Laboratorium chymicum.[176]

Nicolas Lemery, the first Frenchman who completely stripped chemistry of its mysticism, and presented it to the world in all its native simplicity, deserves our particular attention, in consequence of the celebrity which he acquired, and the benefits which he conferred on the science. He was born at Rouen on the 17th of November, 1645. His father, Julian Lemery, was procureur of the Parliament of Normandy, and a protestant. His son, when very young, showed a decided partiality for chemistry, and repaired to an apothecary in Rouen, a relation of his own, in hopes of being initiated into the science; but finding that little information could be procured from him, young Lemery left him in 1666, and went to Paris, where he boarded himself with M. Glaser, at that time demonstrator of chemistry at the Jardin du Roi.

Glaser was a true chemist, according to the meaning at that time affixed to the term—full of obscure notions—unwilling to communicate what knowledge he possessed—and not at all sociable. In two months Lemery quitted his house in disgust, and set out with a resolution to travel through France, and pick up chemical information as he best could, from those who were capable of giving him information on the subject. He first went to Montpelier, where he boarded in the house of M. Vershant, an apothecary in that town. With his situation there he was so much pleased, that he continued in it for three years: he employed himself assiduously in the laboratory, and in teaching chemistry to a number of young students who boarded with his host. Here his reputation gradually increased so much, that he drew round him the professors of the faculty of medicine of Montpelier, and all the curious of the place, to witness his experiments. Here, too, he practised medicine with considerable success.

After travelling through all France, he returned to Paris in 1672. Here he frequented the different scientific meetings at that time held in that capital, and soon distinguished himself by his chemical knowledge. In a few years he got a laboratory of his own, commenced apothecary, and began to give public lectures on chemistry, which were speedily attended by great crowds of students from foreign countries. For example, we are told that on one occasion forty Scotchmen repaired to Paris on purpose to hear his lectures, and those of M. Du Verney on anatomy. The medicines which he prepared in his laboratory became fashionable, and brought him a great deal of money. The magistery of bismuth (or pearl-white), which he prepared as a cosmetic, was sufficient, we are told, to support the whole expense of his house. In the year 1675 he published his Cours de Chimie, certainly one of the most successful chemical books that ever appeared; it ran through a vast number of editions in a few years, and was translated into Latin, German, Spanish, and English.

In 1681 he began to be troubled in consequence of his religious opinions. Louis XIV. was at that time in the height of his glory, entirely under the control of his priests, and zealously bent upon putting an end to the reformed religion in his dominions. Indeed, from the infamous conduct of Charles II. of England, and the bigotry of his successor, a prospect was opened to him, and of which he was anxious to avail himself, of annihilating the reformed religion altogether, and of plunging Europe a second time into the darkness of Roman Catholicism.

Lemery found it expedient, in 1683, to pass over into England. Here he was well received by Charles II.: but England was at that time convulsed with those religious and political struggles, which terminated five years afterwards in the revolution. Lemery, in consequence of this state of things, found it expedient to leave England, and return to France. He took a doctor’s degree at Caen, in Normandy; and, returning to Paris, he commenced all at once practitioner in medicine and surgery, apothecary, and lecturer on chemistry. The edict of Nantes was revoked in 1685, when James II. had assured Louis of his intention to overturn the established religion, and bring Great Britain again under the dominion of the pope. Lemery was obliged to give up practice and conceal himself, in order to avoid persecution. Finding his success hopeless, as long as he continued a protestant, he changed his religion in 1686, and declared himself a Roman catholic. This step secured his fortune: he was now as much caressed and protected by the court and the clergy, as he had been formerly persecuted by them. In 1699 when the Academy of Sciences was new modelled, he was appointed associated chemist, and, on the death of Bourdelin, before the end of that year, he became a pensioner. He died on the 19th of June, 1715, at the age of seventy, in consequence of an attack of palsy, which terminated in apoplexy.

Besides his System of Chemistry, which has been already mentioned, he published the following works:

1. Pharmacopée universelle, contenant toutes les Operations de Pharmacie qui sont en usage dans la Médicine.

2. Traité universelle des Drogues simples mis en ordre alphabétique.

3. Traité de l’Antimoine, contenant l’analyse chimique de ce mineral.

Besides these works, five different papers by Lemery were printed in the Memoirs of the French Academy, between 1700 and 1709 inclusive. These are as follow:

1. Explication physique et chimique des Feux souterrains, des tremblemens de Terre, des Ouragans, des Eclairs et du Tonnere.—This explanation is founded on the heat and combustion produced by the mutual action of iron filings and sulphur on each other, when mixed in large quantities.

2. Du Camphre.

3. Du Miel et de son analyse chimique.

4. De l’Urine de Vache, de ses effets en médicine et de son analyse chimique.

5. Reflexions et Experiences sur le Sublimé Corrosive.—It appears from this paper, that in 1709, when Lemery wrote, corrosive sublimate was considered as a compound of mercury with the sulphuric and muriatic acids. Lemery’s statement, that he made corrosive sublimate simply by heating a mixture of mercury and decrepitated salt, is not easily explained. Probably the salt which he had employed was impure. This is the more likely, because, from his account of the matter which remained at the bottom of the matrass after sublimation, it must have either contained peroxide of iron or peroxide of mercury, for its colour he says was red.

M. Lemery left a son, who was also a member of the French Academy; an active chemist, and author of various papers, in which he endeavours to give a mechanical explanation of chemical phenomena.

Another very active member of the French Academy, at the same time with Lemery, was M. William Homberg, who was born on the 8th of January, 1652, at Batavia, in the island of Java. His father, John Homberg, was a Saxon gentleman, who had been stripped of all his property during the thirty years war. After receiving some education by the care of a relation, he went into the service of the Dutch East India Company, and got the command of the arsenal at Batavia. There he married the widow of an officer, by whom he had four children, of whom William was the second.

His father quitted the service of the India Company and repaired to Amsterdam with his family. Young Homberg studied with avidity: he devoted himself to the law, and in 1674 was admitted advocate of Magdeburg; but his taste for natural history and science was great. He collected plants in the neighbourhood, and made himself acquainted with their names and uses. At night he studied the stars, and learned the names and positions of the different constellations. Thus he became a self-taught botanist and astronomer. He constructed a hollow transparent celestial globe, on which, by means of a light placed within, the principal fixed stars were seen in the same relative positions as in the heavens.

Otto Guericke was at that time burgomaster of Magdeburg. His experiments on a vacuum, and his invention of the air-pump, are universally known. Homberg attached himself to Otto Guericke, and this philosopher, though fond of mystery, either explained to him his secrets, in consequence of his admiration of his genius, or was unable to conceal them from his penetration. At last Homberg, quite tired of his profession of advocate, left Magdeburg and went to Italy. He sojourned for some time at Padua, where he devoted himself to the study of medicine, anatomy, and botany. At Bologna he examined the famous Bologna stone, the nature of which had been almost forgotten, and succeeded in making a pyrophorus out of it. At Rome he associated particularly with Marc-Antony Celio, famous for the large glasses for telescopes which he was able to grind. Nor did he neglect painting, sculpture, and music; pursuits in which, at that time, the Italians excelled all other nations.

From Italy he went to France, and thence passed into England, where he wrought for some time in the laboratory of Mr. Boyle, at that time one of the most eminent schools of science in Europe. He then passed into Holland, studied anatomy under De Graaf, and after visiting his family, went to Wittemberg, where he took the degree of doctor of medicine.

After this he visited Baldwin and Kunkel, to get more accurate information respecting the phosphorus which each had respectively discovered. He purchased a knowledge of Kunkel’s phosphorus, by giving in exchange a meteorological toy of Otto Guericke, now familiarly known, by which the moisture or dryness of the air was indicated—a little man came out of his house and stood at the door in dry weather, but retired under cover in moist weather. He next visited the mines of Saxony, Bohemia, and Hungary: he even went to Sweden, to visit the copper-mines of that country. At Stockholm he wrought in the chemical laboratory, lately established by the king, along with Hjerna, and contributed considerably to the success of that new establishment.

He repaired a second time to France, where he spent some time, actively engaged with the men of science in Paris. His father strongly pressed him to return to Holland and settle as a physician: he at last consented, and the day of his departure was come, when, just as he was going into his carriage, he was stopped by a message from M. Colbert on the part of the king. Offers of so advantageous a nature were made him if he would consent to remain in France, that, after some consideration, he was induced to embrace them.

In 1682 he changed his religion and became Roman catholic: this induced his father to disinherit him. In 1688 he went to Rome, where he practised medicine with considerable success. A few years after he returned to Paris, where his knowledge and discoveries gave him a very high reputation. In 1691 he became a member of the Academy of Sciences, and got the direction of the laboratory belonging to the academy: this enabled him to devote his undivided attention to chemical investigations. In 1702 he was taken into the service of the Duke of Orleans, who gave him a pension, and put him in possession of the most splendid and complete laboratory that had ever been seen. He was presented with the celebrated burning-glass of M. Tchirnhaus, by the Duke of Orleans, and was enabled by means of it to determine many points that had hitherto been only conjectural.

In 1704 he was made first physician to the Duke of Orleans, who honoured him with his particular esteem. This appointment obliging him to reside out of Paris, would have made it necessary for him to resign his seat in the academy, had not the king made a special exemption in his favour. In 1708 he married a daughter of the famous M. Dodart, to whom he had been long attached. Some years after he was attacked by a dysentery, which was cured, but returned from time to time. In 1715 it returned with great violence, and Homberg died on the 24th of September.

His knowledge was uncommonly great in almost every department of science. His chemical papers were very numerous; though there are few of them, in this advanced period of the science, that are likely to claim much attention from the chemical world. His pyrophorus, of which he has given a description in the Mémoires de l’Académie,[177] was made by mixing together human fæces and alum, and roasting the mixture till it was reduced to a dry powder. It was then exposed in a matrass to a red heat, till every thing combustible was driven off. Any combustible will do as a substitute for human fæces—gum, flour, sugar, charcoal, may be used. When a little of this phosphorus is poured upon paper, it speedily catches fire and kindles the paper. Davy first explained the nature of this phosphorus. The potash of the alum is converted into potassium, which, by its absorption of oxygen from the atmosphere, generates heat, and sets fire to the charcoal contained in the powder.

Homberg’s papers printed in the Memoirs of the French Academy amount to thirty-one. They are to be found in the volumes for 1699 to 1714 inclusive.

M. Geoffroy, who was a member of the academy about the same time with Lemery and Homberg, though he outlived them both, and who was an active chemist for a considerable number of years, deserves also to be mentioned here.

Stephen Francis Geoffroy was born in Paris on the 13th of February, 1672, where his father was an apothecary. While a young man, regular meetings of the most eminent scientific men of Paris were held in his father’s house, at which he was always present. This contributed very much to increase his taste for scientific pursuits. After this he studied botany, chemistry, and anatomy in Paris. In 1692 his father sent him to Montpelier, to study pharmacy in the house of a skilful apothecary, who at the same time sent his son to Paris, to acquire the same art in the house of M. Geoffroy, senior. Here he attended the different classes in the university, and his name began to be known as a chemist. After spending some time in Montpelier, he travelled round the coast to see the principal seaports, and was at St. Malo’s in 1693, when it was bombarded by the British fleet.

In 1698 Count Tallard being appointed ambassador extraordinary to London, made choice of M. Geoffroy as his physician, though he had not taken a medical degree. Here he made many valuable acquaintances, and was elected a fellow of the Royal Society. From London he went to Holland, and thence into Italy, in 1700, where he went in the capacity of physician to M. de Louvois. The great object of M. Geoffroy was always natural history, and materia medica. In 1693 he had subjected himself to an examination, and he had been declared qualified to act as an apothecary; but his own object was to be a physician, while that of his father was that he should succeed himself as an apothecary: this in some measure regulated his education. At last he declared his intentions, and his father agreed to them; he became bachelor of medicine in 1702, and doctor of medicine in 1704.

In 1709 he was made professor of medicine in the Royal College. In 1707 he began to lecture on chemistry, at the Jardin du Roi, in place of M. Fagan, and continued to teach this important class during the remainder of his life. In 1726 he was chosen dean of the faculty of medicine; and, after the two years for which he was elected was finished, he was again chosen to fill the same situation. There existed at that time a lawsuit between the physicians and surgeons in Paris; a kind of civil war very injurious to both; and the mildness and suavity of his manners fitted him particularly for being at the head of the body of physicians during its continuance. He became a member of the academy in 1699, and died on the 6th of January, 1731.

The most important of all his chemical labours, and for which he will always be remembered in the annals of the science, was the contrivance which he fell upon, in 1718, of exhibiting the order of chemical decompositions under the form of a table.[178] This method was afterwards much enlarged and improved. Such tables are now usually known by the name of tables of affinity; and, though they have been of late years somewhat neglected, there can be but one opinion of their importance when properly constructed.

M. Geoffroy first communicated to the French chemists the mode of making Prussian blue, as Dr. Woodward did to the English.

Claude Joseph Geoffroy, the younger brother of the preceding, was also a member of the Academy of Sciences, and a zealous cultivator of chemistry. Many of his chemical papers are to be found in the memoirs of the French Academy. He demonstrated the composition of sal ammoniac, which however was known to Glauber. He made many experiments upon the combustion of the volatile oils, by pouring nitric acid on them. He explained the pretended property which certain waters have of converting iron into copper, by showing that in such cases copper was held in solution in the water by an acid, and that the iron merely precipitated the copper, and was dissolved and combined with the acid in its place. He pointed out the constituents of the three vitriols, the green, the blue, and the white; showing that the two former were combinations of sulphuric acid with oxides of iron and copper, and the latter a solution of lapis calaminaris (carbonate of zinc) in the same acid. He has also a memoir on the emeticity of antimony, tartar emetic, and kermes mineral; but it is rather medical than chemical. He determined experimentally the nature of the salt of Seignette, or Rochelle salt, and showed that it was obtained by saturating cream of tartar with carbonate of soda, and crystallizing. It is curious that this discovery was made about the same time by M. Boulduc. I have noticed only a few of the papers of M. Geoffroy, junior; because, though they all do him credit, and contributed to the improvement of chemistry, yet none of them contain any of those great discoveries, which stand as landmarks in the progress of science, and constitute an era in the history of mankind. For the same reason I omit several other names that, in a more minute history of chemistry, would deserve to be particularized.

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CHAPTER VIII.
OF THE ATTEMPTS TO ESTABLISH A THEORY IN CHEMISTRY.

Bacon, Lord Verulam, as early as the commencement of the 17th century, had pointed out the importance of chemical investigations, and had predicted the immense advantages which would result from the science, when it came to be properly cultivated and extended; but he did not himself attempt either to construct a theory of chemistry, or even to extend it beyond the bounds which it had reached before he began to write. Neither did Boyle, notwithstanding the importance of his investigations, and his comparative freedom from the prejudices of the alchymists, attempt any thing like a theory of chemistry; though the observations which he made in his Sceptical Chemist, had considerable effect in overturning, or at least in hastening the downfall of the absurd chemical opinions which at that time prevailed, and the puerile hypotheses respecting the animal functions, and the pathology and treatment of diseases founded on these opinions. The first person who can with propriety be said to have attempted to construct a theory of chemistry, was Beccher.

John Joachim Beccher, one of the most extraordinary men of the age in which he lived, was born at Spires, in Germany, in the year 1635. His father, as Beccher himself informs us, was a very learned Lutheran preacher. As he lost his father when he was very young, and as that part of Germany where he lived had been ruined by the thirty years’ war, his family was reduced to great poverty. However, his passion for information was so great, that he contrived to educate himself by studying what books he could procure, and in this way acquired a great deal of knowledge. Afterwards he travelled through the greatest part of Germany, Italy, Sweden, and Holland.

In the year 1666 he was appointed public professor of medicine in the University of Mentz, and soon after chief physician to the elector. In that capacity he took up his residence in Munich, where he was furnished by the elector with an excellent laboratory: but he soon fell into difficulties, the nature of which does not appear, and was obliged to leave the place. He took refuge in Vienna, where, from his knowledge of finance, he was appointed chamberlain to Count Zinzendorf, and through him acquired so much importance in the eyes of the court, that he was named a member of the newly-erected College of Commerce, and obtained the title of imperial commercial counsellor and chamberlain. But here also he speedily raised up so many enemies against himself, that he found it necessary to leave Vienna, and to carry with him his wife and children. He repaired to Holland, and settled at Haerlem in 1678. Here he was likely to have been successful; but his enemies from Vienna followed him, and obliged him to leave Holland. In 1680 we find him in Great Britain, where he examined the Scottish lead-mines, and smelting-works; and in 1681, and 1682, he traversed Cornwall, and studied the mines and smelting-works of that great mining county; here he suggested several improvements and ameliorations. Soon after this an advantageous proposal was made to him by the Duke of Mecklenburg Gustrow, by means of Count Zinzendorf; but all his projects were arrested by his death, which took place in the year 1682. It is said that he died in London, but I have not been able to find any evidence of this.

It would be a difficult task to particularize his various discoveries, which are scattered through a multiplicity of writings. He was undoubtedly the first discoverer of boracic acid, though the credit of the discovery has usually been given to Homberg.[179] But then he gives no account of boracic acid, nor does he seem to have attended to its qualities. The following is a list of Beccher’s writings:

1. Metallurgia, or the Natural Science of Metals.

2. Institutiones Chymicæ.

3. Parnassus Medicinalis illustrata.

4. Œdipus Chymicus seu Institutiones Chymicæ.

5. Acta laboratorii Chymici Monacensis seu Physica Subterranea.—This, which is the most important of all his works, is usually known by the name of “Physica Subterranea.” This is the sole title affixed to it in the edition published at Leipsic, in 1703, to which Stahl has prefixed a long introduction. It is divided into seven sections. In the first he treats of the creation of the world; in the second he gives a chemical account of the motions and changes which are constantly going on in the earth; in the third he treats of the three principles of all bodies, which he calls earths. The first of these principles of metals and stones is the fusible or stony earth; the second principle of minerals is the fat earth, improperly called sulphur; the third principle is the fluid earth, improperly called mercury; in the fourth section he treats of the action of subterraneous principles, or the formation of mixts; in the fifth he treats of the solution of the three classes of mixts, animals, vegetables, and metals; in the sixth he treats of mixts, in which he gives their chemical constituents. This section is very curious, because it gives Beccher’s views of the constitution of compound bodies. It will be seen from it that he had much more correct notions of the real objects of chemistry, than any of his contemporaries. In the seventh and last section he treats of the accidents and physical affections of subterraneous bodies.

6. Experimentum Chymicum novum quo artificialis et instantanea metallorum generatio et transmutatio, ad oculum demonstratur.—This constitutes the first supplement to the Physica Subterranea.

7. Supplementum secundum in Physicam subterraneam, demonstratio philosophica seu Theses Chymicæ, veritatem et possibilitatem transmutationis metallorum in aurum evincentes.

8. Trifolium Beccherianum Hollandicum.

9. Experimentum novum et curiosum de Minera arenaria perpetua, sive prodromus historiæ seu propositionis Præp. D.D. Hollandiæ ordinibus ab authore factæ, circa auri extractionem mediante arena littorali per modum mineræ perpetuæ seu operationis magnæ fusoriæ cum emolumento. Loco supplementi tertii in Physicam suam subterraneam.

10. Chemical Luckpot, or great chemical agreement; in a collection of one thousand five hundred chemical processes.

11. Foolish Wisdom and wise Folly.

12. Magnalia Naturæ.

13. Tripus Hermeticus fatidicus pandens oracula chemica; seu I. Laboratorium portatile, cum methodo vere spagyricæ seu juxta exigentiam naturæ laborandi. Accessit pro praxi et exemplo; II. Centrum mundi concatenatum seu Duumviratus hermeticus s. magnorum duorum productorum nitri et salis textura et anatomia atque in omnium præcedentium confirmationem adjunctum est; III. Alphabetum Minerale seu viginti quatuor theses de subterraneorum mineralium genesi, textura et analysi; his accessit concordantia mercurii lunæ et menstruorum.

14. Chemical Rose-garden.

15. Pantaleon delarvatus.

16. Beccheri, Lancelotti, etc. Epistolæ quatuor Chemicæ.

Beccher’s great merit was the contrivance of a chemical theory, by which all the known facts were connected together and deduced from one general principle. But as this theory was adopted and considerably modified by Stahl, it will be better to lay a sketch of it before the reader, after mentioning a few particulars of the life and labours of one of the most extraordinary men whom Germany has produced; a man who, in spite of the moroseness and haughtiness of his character, and in spite of the barbarity of his style, raised himself to the very first rank as a man of science; and had the rare or almost unique fortune of giving laws at the same time to two different and important sciences, which he cultivated together, without letting his opinions respecting the one influence him with regard to the other. These sciences were chemistry and medicine.

George Ernest Stahl was born at Anspach, in the year 1660. He studied medicine at Jena under George Wolfgang Wedel; and got his doctor’s degree at the age of twenty-three. Immediately after this he began his career as a public lecturer. In 1687 the Duke of Weimar gave him the title of physician to the court. In 1694 he was named, at the solicitation of Frederick Hoffmann, second professor of medicine in the University of Halle, which had just been established. Hoffmann and he were at that time great friends, though they afterwards quarrelled. Both of them were men of the very highest talents and both were the founders of medical systems which, of course, each was anxious to support. Hoffmann had greatly the superiority in elegance and clearness of style, and in all the amenities of polite manners. But perhaps the moroseness of Stahl, and the obscurity, or rather mysticism of his style, contributed equally with the more amiable qualities of Hoffmann to excite the attention and produce the veneration with which he was viewed by his pupils, and, indeed, by the world at large.

At Halle he continued as a teacher of medicine for twenty-two years. In 1716 he was appointed physician to the King of Prussia. In consequence of this appointment he left Halle, and resided in Berlin, where he died in the year 1734, in the seventy-fifth year of his age. Notwithstanding the great figure that Stahl made as a chemist, there is no evidence that he ever taught that science in any public school. The Berlin Academy had been founded under the superintendence of Leibnitz, who was its first president; and therefore existed when Stahl was in Berlin: but, till it was renovated in 1745 by Frederick the Great, this academy possessed but little activity, and could scarcely, therefore, have stimulated Stahl to attend to chemical science. However, his Chymia rationalis et experimentalis was published in 1720, while he resided in Berlin. The same date is appended to the preface of his Fundamenta Chymiæ; but, from some expressions in that preface, it must, I should think, have been written, not by Stahl, but by some other person.[180] I suspect that the book had been written by some of his pupils, from the lectures of the author while at Halle. If this was really the case, it is obvious that Stahl must have taught chemistry as well as medicine in the University of Halle.

Stahl’s medical theory is not less deserving of notice than his chemical. But it is not the object of this work to enter into medical speculations. Like Van Helmont, he resolved all diseases into the actions of the soul, which was not merely the former of the body, but its ruler and regulator. When any of the functions are deranged, the soul exerts itself to restore them again to their healthy state; and she accomplishes this by what in common language is called disease. The business of a medical man, then, is not to prevent diseases, or to stop them short when they appear; because they are the efforts of the soul, the vis medicatrix naturæ, to restore the deranged state of the functions: but he must watch these diseases, and prevent the symptoms from becoming too violent. He must assist nature to produce the intended effect, and check her exertions when they become abnormal. It was a kind of modification of this theory, or rather a mixture of the Stahlian and Hoffmannian theories, that Dr. Cullen afterwards taught in Edinburgh with so much eclat. And these opinions, so far as medical theories have any influence on practice, still continue in some measure prevalent. Indeed, much of the vulgar practice followed by medical men, chiefly in consequence of the education which they have received, is deduced from these two theories. But it would be too great a digression from the object of this work to enter into any details: suffice it to say, that the rival theories of Hoffmann and Stahl for many years divided the medical world in Germany, if not in the greater part of Europe. It was no small matter of exultation to so young a medical school as Halle, to have at once within its walls two such eminent teachers as Hoffmann and Stahl.

Let us turn our attention to the chemical writings of Stahl. Of these the most important is his Fundamenta Chymiæ dogmaticæ et experimentalis. It is divided, like the chemistry of Boerhaave, into a theoretical and practical part. The perusal of it is very disagreeable, as it is full of German words and phrases, and symbols are almost constantly substituted for words, as was at that time the custom.

His definition of chemistry is much more exact than Boerhaave’s. It is, according to him, the art of resolving compound bodies into their constituents, and of again forming them by uniting these constituents together.

He is inclined to believe with Beccher, that the simple principles are four in number. The mixts are compounds of these principles; and he shows by the doctrine of permutations that if we suppose the simple principles four, then the number of mixts will be 40,340. He treats in the first place of mixts, compounds, and aggregates.

The first object of chemistry is corruption, the second generation. Of these he treats at considerable length, giving an account of the different chemical processes, and of the apparatus employed.

He next treats of salts, which he defines mixts composed of water and earth, both simple and pure, and intimately united. The salts are vitriol, alum, nitre, common salt, and sal ammoniac. He next treats of more compound salts. These are sugar, tartar, salts from the animal and salts from the mineral kingdom, and quicklime.

After this comes sulphur, cinnabar, antimony, the sulphur of vitriol, the sulphur of nitre, resins, and distilled oils. Then he treats of water, which he divides into aqua humida or common water, and aqua sicca or mercury. Next he treats of earths, which are of two kinds, viz., friable earths, such as clay, loam, sand, &c., and metallic earths constituting the bases of the metals.

He next treats of the metals; and, as a preliminary, we have a description of the method of smelting, and operating upon the different metals. The metals are then described successively in the following order: Gold, silver, copper, iron, tin, lead, bismuth, zinc, antimony.

To this part of the system are added three sections. The first treats of mercuries, the second of the philosopher’s stone, and the third of the universal medicine. We must not suppose that Stahl was a believer in these ideal compositions; his object is merely to give a history of the different processes which had been recommended by the alchymists.

The second part of his work is divided into two tracts. The first tract contains three sections. The first of these treats of the nature of solids and fluids, of solutions and menstrua, of the effects of heat and fire, of effervescence and boiling, of volatilization, of fusion and liquefaction, of distillation, of precipitation, of calcination and incineration, of detonation, of amalgamation, of crystallization and inspissation, and of the fixity and firmness of bodies. In the second section we have an account of salts, and of their generation and transmutation, of sulphur and inflammability, of phosphorus, of colours, and of the nature of metals and minerals. In this article he gives short definitions of these bodies, and shows how they may be known. The bodies thus defined are gold, silver, iron, copper, lead, tin, mercury, antimony, sulphur, arsenic, vitriol, common salt, nitre, alum, sal ammoniac, alkalies, and salts; viz., muriatic acid, sulphuric, nitric, and sulphurous.

In the third section he treats of the method of reducing metallic calces, of the mode of separating metals from their scoriæ, of the mode of making artificial gems, and finally of the mode of giving copper a golden colour.

The second tract is divided into two parts. The first part is subdivided into four sections. In the first section he treats of the instruments of chemical motion, of fire, of air, of water, of the most subtile earth or salt. In the second section he treats de subjectis, under the several heads of dissolving aggregates, of triturations and solutions, and of calcinations and combustions. In the third section he treats of the object of chemistry under the following heads: Of chemical corruption, consisting of compounds from liquids, of the separation of solids and fluids, of mixts, of the solution of compounds from solids. In the fourth section he treats of fermentation.

The second part of this second tract treats of chemical generation, and is divided into two sections. In the first section he treats of the aggregate collection of bodies into fluids and solids. The section treats of compositions under the heads of volatile and solid bodies. He gives in the last article an account of the combination of mixts.

The third and last part of this elaborate work discusses three subjects; viz. zymotechnia or fermentation, halotechnia, or the production and properties of salts, and pyrotechnia, in which the whole of the Stahlian doctrine of phlogiston is developed. This third part has all the appearance of having been notes written down by some person during the lectures of Stahl: for it consists of alternate sentences of Latin and German. It is not at all likely that Stahl himself would have produced such a piebald work; but if he lectured in Latin, as was at that time the universal custom, it was natural for a person occupied in taking down the lectures, to write as far as was possible in Latin, but when any of the Latin phrases were lost, or did not immediately occur to memory, it were equally natural to write down the meaning of what the professor stated in the language most familiar to the writer, which was undoubtedly the German.

Another of Stahl’s works is entitled “Opusculum Chymico-physico-medicum,” published at Halle in a thick quarto volume, in the year 1715. It contains a great number of tracts, partly chemical and partly medical, which it is needless to specify. Perhaps the most curious of them all is his dissertation to show the way in which Moses ground the golden calf to powder, dissolved it in water, and obliged the children of Israel to drink it. He shows that a solution of hepar sulphuris (sulphuret of potassium), has the property of dissolving gold, and he draws as a conclusion from his experiments that this was the artifice employed by Moses. We have in the same volume a pretty detailed treatise on metallurgic pyrotechny and docimasy. This is the more curious, because Stahl never appears to have frequented the mines and smelting-houses of Germany. He must, therefore, have drawn his information from books and from experiment.

Another of his books is entitled “Experimenta, Observationes, Animadversiones, CCC. Numero.” An octavo volume, printed at Berlin in 1731. Another of his books is entitled “Specimen Beccherianum.” There are also two chemical books of Stahl, which I have seen only in a French translation, viz., Traité de Soufre and Traité de Sels. These are the only chemical writings of Stahl that I have seen. There are probably others; indeed I have seen the titles of several other chemical works ascribed to him. But as it is doubtful whether he really wrote them or not, I think it unnecessary to specify them here.

Stahl’s writings evince the great progress which chemistry had made even since the time of Beccher. But it is difficult to say what particular new facts, which appear first in his writings were discovered by himself, and what by others. I shall not, therefore, attempt any enumeration of them. His reasoning is more subtile, and his views much more extensive and profound than those of his predecessors. The great improvement which he introduced into chemistry was the employment of phlogiston, to explain the phenomena of combustion and calcination. This theory had been originally broached by Beccher, from whom Stahl evidently borrowed it, but he improved and simplified it so much that the whole credit of it was given to him. It was called the Stahlian theory, and raised him to the highest rank among chemists. The sole objects of chemists for thirty or forty years after his time was to illucidate and extend his theory. It applied so happily to all the known facts, and was supported by experiments, which appeared so decisive that nobody thought of calling it in question, or of interrogating nature in any other way than he had pointed out. It will be requisite, therefore, before proceeding further with this historical sketch, to lay the outlines of the phlogistic theory before the reader.

It was conceived by Beccher and Stahl that all combustible bodies are compounds. One of the constituents they supposed to be dissipated during the combustion, while the other constituent remained behind. Now when combustible bodies are subjected to combustion, some of them leave an acid behind them; while others leave a fixed powdery matter, possessing the properties of an earth, and called usually the calx of the combustible body. The metals are the substances which leave a calx behind them when burnt, and sulphur and phosphorus leave an acid. With respect to those bodies that would not burn, chemists did not speculate much at first; but afterwards they came to think that they consisted of the fixed substance that remained after combustion. Hence the conclusion was natural, that they had already undergone combustion. Thus quicklime possessed properties very similar to the calces of metals. It was natural, therefore, to consider it as a calx, and to believe that if the matter dissipated during combustion could be again restored, lime would be converted into a substance similar to the metals.

Combustibility then, according to this view of the subject, depends upon a principle or material substance, existing in every combustible body, and dissipated during the combustion. This substance was considered to be absolutely the same in all combustible bodies whatever; hence the difference between combustible bodies proceeded from the other principle or number of principles with which this common substance is combined. In consequence of this identity Stahl invented the term phlogiston, by which he denoted this common principle of combustible bodies. Inflammation, with the several phenomena that attend it, depended on the gradual separation of this principle, which being once separated, what remained of the body could no longer be an inflammable substance, but must be similar to the other kinds of matter. It was this opinion that combustibility is owing to the presence of phlogiston, and inflammation to its escape, that constituted the peculiar theory of Beccher, and which was afterwards illustrated by Stahl with so much clearness, and experiments to prove its truth were advanced by him of so much force, that it came to be distinguished by the name of the Stahlian theory.

The identity of phlogiston in all combustible bodies was founded upon observations and experiments of so decisive a nature, that after the existence of the principle itself was admitted, they could not fail to be satisfactory. When phosphorus is made to burn it gives out a strong flame, much heat is evolved, and the phosphorus is dissipated in a white smoke: but if the combustion be conducted within a glass vessel of a proper shape, this white smoke will be deposited on the inside of the glass; it quickly absorbs moisture from the atmosphere, and runs into an acid liquid, known by the name of phosphoric acid. If this liquid be put into a platinum crucible, and gradually heated to redness, the water is dissipated, and a substance remains which, on cooling, congeals into a transparent colourless body like glass: this is dry phosphoric acid. If now we mix phosphoric acid with a quantity of charcoal powder, and heat it sufficiently in a glass retort, taking care to exclude the external air, a portion or the whole of the charcoal will disappear, and phosphorus will be formed possessed of the same properties that it had before it was subjected to combustion. The conclusion deduced from this process appeared irresistible; the charcoal, or a portion of it, had combined with the phosphoric acid, and both together had constituted phosphorus.

Now, in changing phosphoric acid into phosphorus, we may employ almost any kind of combustible substance that we please, provided it be capable of bearing the requisite heat; they will all equally answer, and will all convert the acid into phosphorus. Instead of charcoal we may take lamp-black, or sugar, or resin, or even several of the metals. Hence it was concluded that all of these bodies contain a common principle which they communicate to the phosphoric acid; and since the new body formed is in all cases identical, the principle communicated must also be identical. Hence combustible bodies contain an identical principle, and this principle is phlogiston.

Sulphur by burning is converted into sulphuric acid; and if sulphuric acid be heated with charcoal, or phosphorus, or even sulphur, it is again converted into sulphur. Several of the metals produce the same effect. The reasoning here was the same as with regard to phosphoric acid, and the conclusion was similar.

When lead is kept nearly at a red heat in the open air for some time, being constantly stirred to expose new surfaces to the air, it is converted into the beautiful pigment called red lead; this is a calx of lead. To restore this calx again to the state of metallic lead, we have only to heat it in contact with almost any combustible matter whatever. Pit-coal, peat, charcoal, sugar, flour, iron, zinc, &c., all these bodies then must contain one common principle, which they communicate to red lead, and by so doing convert it into lead. This common principle is phlogiston.

These examples are sufficient to show the reader the way in which Stahl proved the identity of phlogiston in all combustible bodies. And the demonstration was considered as so complete that the opinion was adopted by every chemist without exception.

When we inquire further, and endeavour to learn what qualities phlogiston was supposed to have in its separate state, we find this part of the subject very unsatisfactory, and the opinions very unsettled. Beccher and Stahl represented phlogiston as a dry substance, or of an earthy nature, the particles of which are exquisitely subtile, and very much disposed to be agitated and set in motion with inconceivable velocity. This was called by Stahl motus verticillaris. When the particles of any body are agitated with this kind of motion, the body exhibits the phenomena of heat or ignition, or inflammation, according to the violence and rapidity of the motion.

This very crude opinion of the earthy nature of phlogiston, appears to have been deduced from the insolubility of most combustible substances in water. If we except alcohol, and ether, and gums, very few of them are capable of being dissolved in that liquid. Thus the metals, sulphur, phosphorus, oils, resins, bitumens, charcoal, &c., are well known to be insoluble. Now, at the time that Beccher and Stahl lived, insolubility in water was considered as a character peculiar to earthy bodies; and as those bodies which contain a great deal of phlogiston are insoluble in water, though the other constituents be very soluble in that liquid, it was natural enough to conclude that phlogiston itself was of an earthy nature.

But though the opinions of chemists about the nature and properties of phlogiston in a separate state were unsettled, no doubts were entertained respecting its existence, and respecting its identity in all combustible bodies. Its presence or its absence produced almost all the changes which bodies undergo. Hence chemistry and combustion came to be in some measure identified, and a theory of combustion was considered as the same thing with a theory of chemistry.

Metals were compounds of calces and phlogiston. The different species of metals depend upon the different species of calx which each contains; for there are as many calces (each simple and peculiar) as there are metals. These calces are capable of uniting with phlogiston in indefinite proportions. The calx united to a little phlogiston still retains its earthy appearance—a certain additional portion restores the calx to the state of a metal. An enormous quantity of phlogiston with which some calces, as calx of manganese, are capable of combining, destroys the metallic appearance of the body, and renders it incapable of dissolving in acids.

The affinity between a metallic calx and phlogiston is strong; but the facility of union is greatly promoted when the calx still retains a little phlogiston. If we drive off the whole phlogiston we can scarcely unite the calx with phlogiston again, or bring it back to the state of a metal: hence the extreme difficulty of reducing the calx of zinc, and even the red calx of iron.

The various colours of bodies are owing to phlogiston, and these colours vary with every alteration in the proportion of phlogiston present.

It was observed very early that when a metal was converted into a calx its weight was increased. But this, though known to Beecher and Stahl, does not seem to have had any effect on their opinions. Boyle, who does not seem to have been aware of the phlogistic theory, though it had been broached before his death, relates an experiment on tin which he made. He put a given weight of it into an open glass vessel, and kept it melted on the fire till a certain portion of it was converted into a calx: it was now found to have increased considerably in weight. This experiment he relates in order to prove the materiality of heat: in his opinion a certain quantity of heat had united to the tin and occasioned the increase of weight. This opinion of Boyle was incompatible with the Stahlian theory: for the tin had not only increased in weight, but had been converted into a calx. It was therefore the opinion of Boyle that calx of tin was a combination of tin and heat. It could not consequently be true that calx of tin was tin deprived of phlogiston.

When this difficulty struck the phlogistians, which was not till long after the time of Stahl, they endeavoured to evade it by assigning new properties to phlogiston. According to them it is not only destitute of weight, but endowed with a principle of levity. In consequence of this property, a body containing phlogiston is always lighter than it would otherwise be, and it becomes heavier when the phlogiston makes its escape: hence the reason why calx of tin is heavier than the same tin in the metallic state. The increase of weight is not owing, as Boyle believed, to the fixation of heat in the tin, but to the escape of phlogiston from it.

Those philosophic chemists, who thus refined upon the properties of phlogiston, did not perceive that by endowing it with a principle of levity, they destroyed all the other characters which they had assigned to it. What is gravity? Is it not an attraction by means of which bodies are drawn towards each other, and remain united? And is there any reason for supposing that chemical attraction differs in its nature from the other kinds of attraction which matter possesses? If, then, phlogiston be destitute of gravity, it cannot possess any attraction for other bodies; if it be endowed with a principle of levity, it must have the property of repelling other bodies, for that is the only meaning that can be attached to the term. But if phlogiston has the property of repelling all other substances, how comes it to be fixed in combustible bodies? It must be united to the calces or the acids, which constitute the other principle of these bodies; and it could not be united, and remain united, unless a principle of attraction existed between it and these bases; that is to say, unless it possessed a principle the very opposite of levity.

Thus the fact, that calces are heavier than the metals from which they are formed, in reality overturned the whole doctrine of phlogiston; and the only reason why the doctrine continued to be admitted after the fact was known is, that in these early days of chemistry, the balance was scarcely ever employed in experimenting: hence alterations in weight were little attended to or entirely overlooked. We shall see afterwards, that when Lavoisier introduced a more accurate mode of experimenting, and rendered it necessary to compare the original weights of the substances employed, with the weights of the products, he made use of this very experiment of Boyle, and a similar one made with mercury, to overturn the whole doctrine of phlogiston.

The phlogistic school being thus founded by Stahl, in Berlin, a race of chemists succeeded him in that capital, who contributed in no ordinary degree to the improvement of the science. The most deservedly celebrated of these were Neumann, Pott, Margraaf, and Eller.

Caspar Neumann was born at Zullichau, in Germany, in 1682. He was early received into favour by the King of Prussia, and travelled at the expense of that monarch into Holland, England, France, and Italy. During these travels he had an opportunity of making a personal acquaintance with the most eminent men of science in all the different countries which he visited. On his return home, in 1724, he was appointed professor of chemistry in the Royal College of Physic and Surgery at Berlin, where he delivered a course of lectures annually. During the remainder of his life he enjoyed the situation of superintendent of the Royal Laboratory, and apothecary to the King of Prussia. He died in 1737. He was a Fellow of the Royal Society, and several papers of his appeared in the Transactions of that learned body. The following is a list of these papers, all of which were written in Latin:

1. Disquisitio de camphora.

2. De experimento probandi spiritum vini Gallici, per quam usitato, sed revera falso et fallaci.

Some merchants in Holland, England, Hamburg, and Dantzic, were in possession of what they considered an infallible test to distinguish French brandy from every other kind of spirit. It was a dusky yellowish liquid. When one or two drops of it were let fall into a glass of French brandy, a beautiful blue colour appeared at the bottom of the glass, and when the brandy is stirred, the whole liquid becomes azure. But if the spirit tried be malt spirit, no such colour appears in the glass. Neumann ascertained that the test liquid was merely a solution of sulphate of iron in water, and that the blue colour was the consequence of the brandy having been kept in oak casks, and thus having dissolved a portion of tannin. Every spirit will exhibit the same colour, if it has been kept in oak casks.

3. De salibus alkalino-fixis.

4. De camphora thymi.

5. De ambragrysea.

His other papers, published in Germany, are the following: