In philosophy the Jews had been gradually emanc.i.p.ating themselves from the influence of ancient traditions; their advance in this direction is shown by the active manner in which they aided in the development of Neo-platonism. After the destruction of Jerusalem all Syria and Mesopotamia were full of Jewish schools; but the great philosophers, as well as the great merchants of the nation, were residents of Alexandria.

Persecution and dispersion, if they served no other good purpose, weakened the grasp of the ecclesiastic. Perhaps, too, repeated disappointments in an expected coming of a national temporal Messiah had brought those who were now advanced in intellectual progress to a just appreciation of ancient traditions. In this mental emanc.i.p.ation their physicians took the lead. For long, while their pursuits were yet in infancy, a bitter animosity had been manifested toward them by the Levites, whose manner of healing was by prayer, expiatory sacrifice, and miracle; or, if they descended to less supernatural means, by an application of such remedies as are popular with the vulgar everywhere.

Thus, to a person bitten by a mad dog, they would give the diaphragm of a dog to eat. As examples of a cla.s.s of men soon to take no obscure share in directing human progress may be mentioned Hannina, A.D. 205, often spoken of by his successors as the earliest of Jewish physicians; Samuel, equally distinguished as an astronomer, accoucheur, and oculist, the inventor of a collyrium which bore his name; Rab, an anatomist, who wrote a treatise on the structure of the body of man as ascertained by dissections, thereby attaining such celebrity that the people, after his death, used the earth of his grave as a medicine; Abba Oumna, whose study of insanity plainly shows that he gave a material interpretation to the national doctrine of possession by devils, and replaced that strange delusion by the scientific explanation of corporeal derangement.

This honourable physician made it a rule never to take a fee from the poor, and never to make any difference in his a.s.siduous attention between them and the rich. These men may be taken as a type of their successors to the seventh century, when the Oriental schools were broken up in consequence of the Arab military movements. In the Talmudic literature there are all the indications of a transitional state, so far as medicine is concerned; the supernatural seems to be pa.s.sing into the physical, the ecclesiastical is mixed up with the exact: thus a rabbi may cure disease by the ecclesiastical operation of laying on of hands; but of febrile disturbances, an exact, though erroneous explanation is given, and paralysis of the hind legs of an animal is correctly referred to the pressure of a tumour on the spinal cord. Some of its aphorisms are not devoid of amusing significance: "Any disease, provided the bowels remain open; any kind of pain, provided the heart remain unaffected; any kind of uneasiness, provided the head be not attacked; all manner of evils, except it be a bad woman."

[Sidenote: The Arabs affiliate with them.]

[Sidenote: Rise of Jewish physicians to influence.]

[Sidenote: They found medical colleges,]

[Sidenote: and promote science and literature.]

At first, after the fall of the Alexandrian school, it was all that the Jewish physicians could do to preserve the learning that had descended to them. But when the tumult of Arabic conquest was over, we find them becoming the advisers of crowned heads, and exerting, by reason of their advantageous position, their liberal education, their enlarged views, a most important influence on the intellectual progress of humanity. Maser Djaivah, physician to the Khalif Moawiyah, was distinguished at once as a poet, a critic, a philosopher; Haroun, a physician of Alexandria, whose Pandects, a treatise unfortunately now lost, are said to have contained the first elaborate description of the small-pox and method of its treatment. Isaac Ben Emran wrote an original treatise on poisons and their symptoms, and others followed his example. The Khalif Al Raschid, who maintained political relations with Charlemagne by means of Jewish envoys, set that monarch an example by which indeed he was not slow to profit, in actively patronising the medical college at Djondesabour, and founding a university at Bagdad. He prohibited any person from practising medicine until after a satisfactory examination before one of those faculties. In the East the theological theory of disease and of its cure was fast pa.s.sing away. Of the school at Bagdad, Joshua ben Nun is said to have been the most celebrated professor, the school itself actively promoting the translation of Greek works into Arabic--not alone works of a professional, but also those of a general kind. In this manner the writings of Plato and Aristotle were secured; indeed, it is said that almost every day camels laden with volumes were entering the gates of Bagdad. To add to the supply, the Emperor Michael III. was compelled by treaty to furnish Greek books. The result of this intellectual movement could be no other than a diffusion of light.

Schools arose in Ba.s.sora, Ispahan, Samarcand, Fez, Morocco, Sicily, Cordova, Seville, Granada.

[Sidenote: Intermingling of magic and sorcery.]

[Sidenote: Dedication of portions of matter and time to the supernatural.]

[Sidenote: Origin of the week.]

Through the Nestorians and the Jews the Arabs thus became acquainted with the medical science of Greece and Alexandria; but to this was added other knowledge of a more sinister kind, derived from Persia, or perhaps remotely from Chaldee sources, the Nestorians having important Church establishments in Mesopotamia, and the Jews having been long familiar with that country; indeed, from thence their ancestors originally came.

More than once its ideas had modified their national religion. This extraneous knowledge was of an astrological or magical nature, carried into practice by incantations, amulets, charms, and talismans. Its fundamental principle was that the planetary bodies exercise an influence over terrestrial things. As seven planets and seven metals were at that time known--the sun, the moon, Mars, Mercury, Jupiter, Venus, Saturn, being the planets of astrology--a due allotment was made.

Gold was held sacred to the sun, silver to the moon, iron to Mars, etc.

Even the portions of time were in like manner dedicated; the seven days of the week were respectively given to the seven planets of astrology.

The names imposed on those days, and the order in which they occur, are obviously connected with the Ptolemaic hypothesis of astronomy, each of the planets having an hour a.s.signed to it in its order of occurrence, and the planet ruling first the hour of each day giving its name to that day. Thus arranged, the week is a remarkable instance of the longevity of an inst.i.tution adapted to the wants of man. It has survived through many changes of empire, has forced itself on the ecclesiastical system of Europe, which, unable to change its idolatrous aspect, has encouraged the vulgar error that it owes its authenticity to the Holy Scriptures, an error too plainly betrayed by the pagan names that the days bear, and also by their order of occurrence.

These notions of dedicating portions of matter or of time to the supernatural were derived from the doctrine of a universal spirit or soul of the world, extensively believed in throughout the East. It underlies, as we have seen in Chapter III., all Oriental theology, and is at once a very antique and not unphilosophical conception. Of this soul the spirit of man was by many supposed to be a particle like a spark given off from a flame. All other things, animate or inanimate, brutes, plants, stones, nay, even natural forms, rivers, mountains, cascades, grottoes, have each an indwelling and animating spirit.

[Sidenote: Alexandrian necromancy.]

Amulets and charms, therefore, did not derive their powers from the material substance of which they consisted, but from this indwelling spirit. In the case of man, his immaterial principle was believed to correspond to his personal bodily form. Of the two great sects into which the Jewish nation had been divided, the Pharisees accepted the a.s.syrian doctrine; but the Sadducees, who denied the existence of any such spirit, boasted that theirs was the old Mosaic faith, and denounced their antagonists as having been contaminated at the time of the Babylonian captivity, before which catastrophe, according to them, these doctrines were unheard of in Jerusalem. In Alexandria, among the leading men there were many adherents to these opinions. Thus Plotinus wrote a book on the a.s.sociation of daemons with men, and his disciple Porphyry proved practically the possibility of such an alliance; for, repairing to the temple of Isis along with Plotinus and a certain Egyptian priest, the latter, to prove his supernatural power, offered to raise up the spirit of Plotinus himself in a visible form. A magical circle was drawn on the ground, surrounded with the customary astrological signs, the invocation commenced, the spirit appeared, and Plotinus stood face to face with his own soul. In this successful experiment it is needless to inquire how much the necromancer depended upon optical contrivances, and how much upon an alarmed imagination. But if thus the spirit of a living man could be called up, how much more likely the souls of the dead.

[Sidenote: These ideas originate in Pantheism.]

In reality, these wild doctrines were connected with Pantheism, which was secretly believed in everywhere; for, though, in a coa.r.s.e mode of expression, a distinction seemed thus to be made between matter and spirit, or body and soul, it was held by the initiated that matter itself is a mere shadow of the spirit, and the body a delusive semblance of the soul.

[Sidenote: The black art.]

In the eighth century, many natural facts of a surprising and unaccountable description, well calculated to make a profound impression upon those who witnessed them, had acc.u.mulated. They were such as are now familiar to chemists. Vessels tightly closed were burst open when tormented in the fire, apparently by some invisible agency; intangible vapours condensed into solids; from colourless liquids gaudy precipitates were suddenly called into existence; flames were disengaged without any adequate cause; explosions took place spontaneously. So much that was unexpected and unaccountable justified the t.i.tle of "the occult science," "the black art." From being isolated marvels unconnected with one another, these facts had been united. The Chaldee notions of a soul of the world, and of indwelling spirits, had furnished a thread on which all these pearls, for such they proved to be, might be strung.

[Sidenote: The Arabians fall into these delusions,]

With avidity--for there is ever a charm in the supernatural--did the Arabs receive from their Nestorian and Jewish medical instructors these mystical interpretations along with true knowledge. And far from resting satisfied with what their masters had thus delivered, they proceeded forthwith to improve and extend it for themselves. They submitted all kinds of substances to all kinds of operations, greatly improving the experimental process they had been taught. By exposing various bodies to the fire, they found it possible to extract from them more refined portions, which seemed to concentrate in themselves the qualities pertaining in a more diffuse way to the substances from which they had been drawn. These, since they were often invisible at their first disengagement, yet capable of bursting open the strongest vessels, and sometimes of disappearing in explosions and flames, they concluded must be the indwelling spirit or soul of the body, from which the fire had driven them forth. It was the Chaldee doctrine realized. Thus they obtained the spirit of wine, the spirit of salt, the spirit of nitre. We still retain in commerce these designations, though their significance is lost. When first introduced they had a strictly literal meaning.

Alchemy, with its essences, quintessences, and spirits, was Pantheism materialized. G.o.d was seen to be in everything, in the abstract as well as the concrete, in numbers as well as realities.

[Sidenote: and the Christians also.]

Antic.i.p.ating what will have hereafter to be considered in detail, I may here remark that it was not the Mohammedan alone who delivered himself up to these mystic delusions; Christendom was prepared for them also. In its opinion, the earth, the air, the sea, were full of invisible forms.

With more faith than even by paganism itself was the supernatural power of the images of the G.o.ds accepted, only it was imputed to the influence of devils. The lunatic was troubled by a like possession. If a spring discharged its waters with a periodical gushing of carbonic acid gas, it was agitated by an angel; if an unfortunate descended into a pit and was suffocated by the mephitic air, it was by some daemon who was secreted; if the miner's torch produced an explosion, it was owing to the wrath of some malignant spirit guarding a treasure, and whose solitude had been disturbed. There was no end to the stories, duly authenticated by the best human testimony, of the occasional appearance of such spirits under visible forms; there was no grotto or cool thicket in which angels and genii had not been seen, no cavern without its daemons. Though the names were not yet given, it was well understood that the air had its sylphs, the earth its gnomes, the fire its salamanders, the water its undines; to the day belonged its apparitions, to the night its fairies. The foul air of stagnant places a.s.sumed the visible form of daemons of abominable aspect; the explosive gases of mines took on the shape of pale-faced, malicious dwarfs, with leathery ears hanging down to their shoulders, and garments of grey cloth. Philosophical conceptions can never be disentangled from social ideas; the thoughts of man will always gather a tincture from the intellectual medium in which he lives.

In Christendom, however, the chief application of these doctrines was to the relics of martyrs and saints. As with the amulets and talismans of Mesopotamia, these were regarded as possessing supernatural powers. They were a sure safeguard against evil spirits, and an unfailing relief in sickness.

[Sidenote: Trans.m.u.tation of metals--Alchemy.]

[Sidenote: Philosopher's stone.]

A singular force was given to these mystic ideas by the peculiar direction they happened to take. As there are veins of water in the earth, and apertures through which the air can gain access, an a.n.a.logy was inferred between its structure and that of an animal, leading to an inference of a similarity of functions. From this came the theory of the development of metals in its womb under the influence of the planets, the pregnant earth spontaneously producing gold and silver from baser things after a definite number of lunations. Already, however, in the doctrine of the trans.m.u.tation of metals, it was perceived that to Nature the lapse of time is nothing--to man it is everything. To Nature, when she is trans.m.u.ting a worthless into a better metal, what signify a thousand years? To man, half a century embraces the period of his intellectual activity. The aim of the cultivator of the sacred art should be to shorten the natural term; and, since we observe the influence of heat in hastening the ripening of fruits, may we not reasonably expect that duly regulated degrees of fire will answer the purpose? by an exposure of base material in the furnace for a proper season, may we not antic.i.p.ate the wished for event? The Emperor Caligula, who had formerly tried to make gold from orpiment by the force of fire, was only one of a thousand adepts pursuing a similar scheme.

Some trusted to the addition of a material substance in aiding the fire to purge away the dross of the base body submitted to it. From this arose the doctrine of the powder of projection and the philosopher's stone.

[Sidenote: Trans.m.u.tation and transubstantiation.]

This doctrine of the possibility of trans.m.u.ting things into forms essentially different steadily made its way, leading, in the material direction, to alchemy, the art of making gold and silver out of baser metals, and in theology to transubstantiation. Trans.m.u.tation and transubstantiation were twin sisters, destined for a world-wide celebrity; one became allied to the science of Mecca, the other to the theology of Rome.

[Sidenote: The elixir of life.]

[Sidenote: Potable gold.]

[Sidenote: Chemical waters.]

While thus the Arabs joined in the pursuit of alchemy, their medical tendencies led them simultaneously to cultivate another ancient delusion, the discovery of a universal panacea or elixir which could cure all diseases and prolong life for ever. Mystical experimenters for centuries had been ransacking all nature, from the yellow flowers which are sacred to the sun, and gold his emblem and representative on earth, down to the vilest excrements of the human body. As to gold, there had been gathered round that metal many fict.i.tious excellences in addition to its real values; it was believed that in some preparation of it would be found the elixir vitae. This is the explanation of the unwearied attempts at making potable gold, for it was universally thought that if that metal could be obtained in a dissolved state, it would const.i.tute the long-sought panacea. Nor did it seem impossible so to increase the power of water, as to impart to it new virtues, and thereby enable it to accomplish the desired solution. Were there not natural waters of very different properties? were there not some that could fortify the memory, others destroy it; some re-enforce the spirits, some impart dulness, and some, which were highly prized, that could secure a return of love?

It had been long known that both natural and artificial waters can permanently affect the health, and that instruments may be made to ascertain their qualities. Zosimus, the Panopolitan, had described in former times the operation of distillation, by which water may be purified; the Arabs called the apparatus for conducting that experiment an alembic. His treatise on the virtues and composition of waters was conveyed under the form of a dream, in which there flit before us fantastically white-haired priests sacrificing before the altar; cauldrons of boiling water, in which there are walking about men a span long; brazen-clad warriors in silence reading leaden books, and sphinxes with wings. In such incomprehensible fictions knowledge was purposely, and ignorance conveniently concealed.

[Sidenote: The Arabs originate scientific chemistry.]

The practical Arabs had not long been engaged in these fascinating but wild pursuits, when results of very great importance began to appear. In a scientific point of view, the discovery of the strong acids laid the true foundation of chemistry; in a political point of view, the invention of gunpowder revolutionized the world.

[Sidenote: Gunpowder and fireworks.]

There were several explosive mixtures. Automatic fire was made from equal parts of sulphur, saltpetre, and sulphide of antimony, finely pulverized and mixed into a paste, with equal parts of juice of the black sycamore and liquid asphaltum, a little quick-lime being added. It was directed to keep the material from the rays of the sun, which would set it on fire.

[Sidenote: Incombustible men.]

Of liquid or Greek fire we have not a precise description, since the knowledge of it was kept at Constantinople as a state secret. There is reason, however, to believe that it contained sulphur and nitrate of potash mixed with naphtha. Of gunpowder, Marcus Graecus, whose date is probably to be referred to the close of the eighth century, gives the composition explicitly. He directs us to pulverize in a marble mortar one pound of sulphur, two of charcoal, and six of saltpetre. If some of this powder be tightly rammed in a long narrow tube closed at one end, and then set on fire, the tube will fly through the air: this is clearly the rocket. He says that thunder may be imitated by folding some of the powder in a cover and tying it up tightly: this is the cracker.

It thus appears that fireworks preceded fire-arms. To the same author we are indebted for prescriptions for making the skin incombustible, so that we may handle fire without being burnt. These, doubtless, were received as explanations of the legends of the times, which related how miracle-workers had washed their hands in melted copper, and sat at their ease in flaming straw.

[Sidenote: Arabian chemists.]

Among the Saracen names that might be mentioned as cultivators of alchemy, we may recall El-Rasi, Ebid Durr, Djafar or Geber, Toghrage, who wrote an alchemical poem, and Dschildegi, one of whose works bears the significant t.i.tle of "The Lantern." The definition of alchemy by some of these authors is very striking: the science of the balance, the science of weight, the science of combustion.

[Sidenote: Djafar discovers nitric acid and aqua regia,]

[Sidenote: and that oxidation increases weight.]

[Sidenote: He solves the problem of potable gold.]

To one of these chemists, Djafar, our attention may for a moment be drawn. He lived toward the end of the eighth century, and is honoured by Rhazes, Avicenna, and Kalid, the great Arabic physicians, as their master. His name is memorable in chemistry, since it marks an epoch in that science of equal importance to that of Priestley and Lavoisier. He is the first to describe nitric acid and aqua regia. Before him no stronger acid was known than concentrated vinegar. We cannot conceive of chemistry as not possessing acids. Roger Bacon speaks of him as the magister magistrorum. He has perfectly just notions of the nature of spirits or gases, as we call them; thus he says, "O son of the doctrine, when spirits fix themselves in bodies, they lose their form; in their nature they are no longer what they were. When you compel them to be disengaged again, this is what happens: either the spirit alone escapes with the air, and the body remains fixed in the alembic, or the spirit and body escape together at the same time." His doctrine respecting the nature of the metals, though erroneous, was not without a scientific value. A metal he considers to be a compound of sulphur, mercury, and a.r.s.enic, and hence he infers that trans.m.u.tation is possible by varying the proportion of those ingredients. He knows that a metal, when calcined, increases in weight, a discovery of the greatest importance, as eventually brought to bear in the destruction of the doctrine of Phlogiston of Stahl, and which has been imputed to Europeans of a much later time. He describes the operations of distillation, sublimation, filtration, various chemical apparatus, water-baths, sand-baths, cupels of bone-earth, of the use of which he gives a singularly clear description. A chemist reads with interest Djafar's antique method of obtaining nitric acid by distilling in a retort Cyprus vitriol, alum, and saltpetre. He sets forth its corrosive power, and shows how it may be made to dissolve even gold itself, by adding a portion of sal ammoniac. Djafar may thus be considered as having solved the grand alchemical problem of obtaining gold in a potable state. Of course, many trials must have been made on the influence of this solution on the animal system, respecting which such extravagant antic.i.p.ations had been entertained. The disappointment that ensued was doubtless the reason that the records of these trials have not descended to us.