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In a cloister or a pew,
The mother only with fond care
Since thy throne thou dost not place,
ON THE CHEMISTRY OF THE ANCIENTS.
If we are guided by the greatest number of etymologists, there needs no deep research to demonstrate the antiquity of chemistry. Its name seems to declare its origin. It is agreed almost by all, that it was first cultivated in Egypt, the country of Cham, of whom it is supposed primarily to have taken the name Chemeia sive Chemia, the science of Cham.* But without entering here into a philological discussion, I shall content myself with considering whether the ancients were chemists, and to what degree; and I hope to make it appear, that they not only knew that art scientifically, but had such an insight into some particulars, that in those points they excelled the moderns.
The first instance that occurs, for ascertaining the antiquity of the science, is of a very remote date. Nobody, I think, will disallow that Tubal-Cain, and those who with him found out the method of working in brass and iron, must have been able chemists. In reality it was impossi
In the one hundred and fifth psalm, Egypt is called “ The land of Cham.” According to Bochart, the Coptes called themselves Chemi or Chami; and Plutarch, in his Isis and Osiris, speaking of a district in Egypt, names it Chamia quasi Chimia. Another etymology is assigned to this word, by deriving it from the Arabian kema, occultare, to conceal ; because chemistry is in the nature of an occult art.
ble to work upon these metals, without first knowing the art of digging them out of the mine, and refining and separating them from the ore ; all which are chemical operations, and must have been at first invented by those who excelled in the art, however afterwards they might be put in practice by the meanest artizans. Those who are engaged in the working of copper mines, for instance, and know that the metal itself must pass above a dozen times through the fire, before it can acquire its proper colour and ductility, will easily enter into this sentiment. It appears to me needless to bring together here all the passages of heathen historians, which speak of Vulcan in the same manner as the sacred author does of Tubal-Cain ; or to show from the resemblance, and as it were identity of names, that all of them relate to one and the same person. That would occupy too long a digression. It is enough to observe, that those authors represent Vulcan as skilled in operating upon iron, copper, gold, silver, and all the other bodies capable of sustaining the action of fire.
I likewise pass over whatever carries in it the air of fable ; such as the story of the golden fleece ; the golden apples that grew in the garden of Hesperides; the reports of Manethon and Josephus with relation to Seth's pillars, whence deductions have been made in favour of the translation of metals. I come to facts more real and established ; and, for the sake of chronological order, shall still adhere to the sacred text in considering an action of Moses, who, having broken the golden calf, reduced it into powder, to be mingled with water, and given to the Israelites to drink; in one word he rendered the gold potable ; an operation so difficult, that it is entirely impracticable to most of the chemists of our days, and owned by Boerhaave, to be of so exalted a kind, that it was unknown in his days even to the most skilful. Yet it must be admitted, that it has been looked upon by some able chemists as practicable, who at the same time acknowledge it to be a most remarkable proof of Moses's eminent skill in all the wisdom of the Egyptians. For how, without the aid of chemistry, could Moses have dissolved the golden calf, and that too without applying corrosives, which would have poisoned all who afterwards drank of the water? Yet this is to be done, and in a short time too, though there be but one way of doing it. Frederick the Third, king of Denmark, curious to put this operation into practice, engaged some able chemists of his time to attempt it. After many trials, they at last succeeded, but it was in following the method of Moses, by first of all reducing the gold into small parts by means of fire, and then pounding it in a mortar along with water, till it was so far dissolved as to become potable. This fact cannot be called in question, nor has it any thing supernatural about it. We know that Moses was instructed in all the learning of the Egyptians, among whom the sciences were cultivated with all manner of success, and from whom the most eminent philosophers of Greece derived all their knowledge. That they were not unworthy
of the reputation they acquired, might be shewn from this single article on chemistry.
How the Egyptians formed that cement, which they applied in rearing those monuments which still subsist, remains a secret yet to us unknown; though it be past all doubt, that they prepared it in a chemical way, so hidden however from us, that we daily lament the loss of it. They must also have had some method of tempering steel, far superior to ours, as the deep and sharp inscriptions on their obelisks and temples abundantly testify. The numberless mummies which still endure, after so long a course of ages, proves that the Egyptians carried chemistry to a very high degree of excellence. In their mummies alone there is such a series and contexture, of operations, that some of them still remain unknown, notwithstanding all the attempts of the ablest moderns to recover them. The art of embalming bodies, for example, and preserving them for many ages, is absolutely lost. All the essays to restore this art have proved ineffectual; nor have the reiterated analyses made of mummies, to discover the ingredients of which they are composed, had any better success. Some moderns have attempted, by certain preparations, to preserve dead bodies entire, but all to no purpose. The mummies of Lewis de Bils, or Bilsius, of Copenhagen, who flourished about 1680, have long since been in a state of corruption. There were also, in the composition of the Egyptian mummies, many things beside, which fall within the verge of chemistry; such as their gilding,* so very fresh, as if it were but of fifty years' standing; and their stained silk, so vivid in its colours, though after a series of thirty ages. In the British museum there was, and may be still, a mummy covered over with fillets of granated glass, various in colour, which shews that these people, at that time, understood not only the making of glass, but could paint it to their liking. It may be remarked here, that the ornaments of glass, with which that mummy is bedecked, are tinged with the same colours, and set off in the same taste, as the dyes in which almost all other mummies are painted; so that it is probable, that this kind of ornaments, being very expensive, was reserved for personages of the first rank only; whilst others, who could not afford this, contented themselves with an imitation of it in painting.
It would be easy to make a more extensive enumeration of the particulars of the chemical processes which altogether concurred towards the composition of a mummy; but I proceed now to take notice of their manner of painting upon linen, which, if I mistake not, is still a secret to
After having drawn the outlines of their design upon the piece of linen, they filled each compartment of it with different sorts of gums, proper to absorb the various colours : so that none of them could be dis
That the ancients understood the art of gilding with beaten or water gold is attested by Pliny. Æs inaurari argento vivo, legitimum erat.-Hist: Nat: lib. 33, c. 3.
tinguished from the whiteness of the cloth. Then they dipped it for a moment in a cauldron full of boiling liquor, prepared for the purpose; and drew it thence, painted in all the colours they intended. And what was very remarkable, the colours neither decayed by time, nor faded in washing; the caustic, impregnating the liquor in which it was dipt, having penetrated and fixed every colour intimately through the whole contexture of the cloth. This single instance is sufficieut to give us a very high conception of the progress that chemistry had made among the Egyptians, though their history affords a thousand others of a similar kind not to be wondered at among a people so very active and industrious, where even the lame, the blind, and the maimed, were in constant employment; and so little were the Egyptians subject to envy or jealousy, that they inscribed their discoveries in the arts and sciences upon pillars reared in holy places, in order to omit nothing that might contribute to public utility. The emperor Adrian attests the first part of their character, in a letter written to the consul Servianus, upon presenting him with three very curious cups of glass, which, like a pigeon's neck, reflected, on whatever side they were viewed, a variety of colours, representing those of the precious stone called obsidianum, 'which some commentators have imagined to be the cats-eye, and others the opal.
This art of imitating precious stones was not peculiar to the Egyptians; the Greeks, who, indeed, derived their knowledge from those great masters, were also very skilful in this branch of chemistry. They could give to a composition of chrystal, all the different tints of any precious stone they wanted to imitate. Pliny, Theophrastus, and many others, give some instances of this; but they most remarkably excelled in an exact imitation of the ruby, the hyacinth, the emerald, and the sapphire.
I insist not upon what Diodorous Siculus says, that some of the Egyptian kings had the art of extracting gold from a sort of white marble ; nor upon what Strabo reports of their manner of preparing nitre, and the considerable number of mortars of granite that were to be seen in his time at Memphis, which were intended for chemical purposes; but I cannot in silence pass over their hatching the eggs of hens, geese, and other fowls, at all seasons, and in different ways, first renewed among the moderns by Reaumur, and now daily practised in London and Paris. The method adopted by Reaumur was precisely that of the Egyptians, according to the testimony of Diodorus Siculus, Aristotle, and Flavius Vopiscus.
Chemistry being a principal branch of medicine, it will not be amiss to mention some particulars, wherein the Egyptians have contributed to the perfection of that science. I set aside the history of Æsculapius, who was instructed by Mercury or Hermes, and I come to facts. Their pharmacy depended much on chemistry ; witness their manner of extracting
oil, and preparing opium, for alleviating acute pains, or relieving the mind from melancholy thoughts. Homer seems to have had this last in view, when he introduces Helen as ministring to Telemachus a medical preparation of this kind. They also made a composition or preparation of a clay or fuller's earth, adapted to the relief of many disorders, particularly to render the fleshy parts dry, and thence to cure the dropsy and the hemorrhoids. They knew all the different ways of composing salts, nitre, alum, sal cyrenaïc or ammoniac, so called by them on account of its being found in the environs of the temple of Jupiter Ammon. They made use of the litharge of silver, the rust of iron, and calcined alum, in the cure of ulcers, cuts, boils, defluxions of the eyes, pains of the head, &c., and of pitch against the bite of serpents. They successfully applied caustics. They knew every different way of preparing plants, herbs, and grain, whether for medicine or beverage. Beer had its origin among them,* a circumstance very little known. Their unguents were of the highest estimation, and most lasting; and their using remedies, taken from metallic substances, is so manifest in the writings of Pliny and Dioscorides, that it would be needless, nay tedious, to enter into further details. Dioscorides, especially, often makes mention of their metallic preparations, such as burnt lead, ceruse, verdigrease, and burnt antimony; all which they made use of in their plaisters, and other external applications. It should be observed here, that I have had nothing in view but the pharmacy of the Egyptians, otherwise I might have made mention of the Theriæ, that famous composition of Andromachus the physician of Nero, which has at all times been in bigh estimation, and is now in as much repute as ever.
What little I have advanced respecting the medicinal chemistry of the ancients, must suffice upon this occasion; the Greeks and Romans presenting too vast a field to be comprised in an article of this kind. Hippocrates especially, the contemporary and friend of Democritus, was remarkably assiduous in the cultivation of chemistry. He not only understood the general principles of it, but was an adept in many of its most useful combinations. Passages are quoted from Plato, that are now received as axioms in chemistry. Galen knew that the energy of fire might be applied to many important purposes, and that by the instrumentality of it many secrets in nature were to be discovered, which otherwise must for ever lie hid ; and he gives many instances of this in several parts of his writings. Dioscorides has transmitted to us many of the mineral operations of the ancients, and in particular that of extracting quicksilver from cinnabar, which is in effect an extract description of distillation.
These are abundant proofs of the genius, industry, science, and civilization of the ancient Egyptians, and if their posterity are now degenerated
This fact is confirmed by Pliny. Conficitur potus ex Hordeo, quem Zythum vocant, odoris et saporis jucunditate vero non multum cedens.-Lib. 13, c. 5.