It is highly curious to find this idea presented in a novel and perhaps an exaggerated form by a writer of the sixteenth century. This was Fra Evangelista Quattrami of Gubbio, semplicista, or master of the still-room, to the Cardinal d’Este. He wrote a book entitled, The true declaration of all the metaphors, similitudes, and riddles of the ancient Alchemical Philosophers, as well among the Chaldeans and Arabians as the Greeks and Latins.[111] According to this work, the potable gold; the elixir of life; the quintessence, and the philosopher’s stone were nothing but fantastic names for the fire itself which was used in distillation and other chemical operations. In this the Frate may possibly have touched the true sense of Al Kindi at least, who, in his commentary on the Meteora,[112] speaks of fire as if it were the all in all of the alchemist.

While the primitive chemical practice followed the progress of the arts which it served, the new theory of alchemy, with the ever-growing tradition of fantastic experiments arising out of it, found different and less direct channels in its descent from ancient to modern times. It has been customary to speak of the Arabs as if that nation had been the chief means of transmitting the knowledge of Greek doctrine to our mediæval scholars, but we now know that there was a previous link in the chain of intellectual succession. This was supplied by the care and industry of the Syrian subjects of the early Caliphs, nor did their learned men play a less important part in the history of chemistry than in that of the other sciences. Sergius of Resaina, a scholar of the fifth century, was, it is said, the first Syrian who attempted to translate the Greek chemists, several of whom mention him by name. The chief development of this work belongs, however, to the ninth and tenth centuries, and its glory must ever remain with the great school of Bagdad. Chemical treatises composed by Democritus and Zosimus[113] were there and then rendered into Syriac, as may be seen by the manuscripts still preserved in the British Museum and at Cambridge.

It was not long before the Arabs themselves began to feel powerfully the intellectual impulse thus communicated to them in the heart of a country which they had made their own. Khaled ben Yezid ibn Moauia, who died in the year 708, is said by their historians to have been the first of that nation who devoted his attention to chemistry. In his case the filiation of doctrine would seem very plain, as he was the pupil of a Syrian monk named Mariannos. Djabar, the Geber of Western writers, followed in the same line of study, and from the ninth century there was a regular school of Arabian chemists whose labours may be studied in the manuscript collections of Paris and Leyden.

In the eleventh century appeared a curious phenomenon, in the shape of a dispute among the Arabians of that day regarding the truth of the tradition which pronounced the transmutation of metals possible. The unwearied but still unavailing experiments which had now been carried on through several ages, produced at last their inevitable effect in the shape of philosophic doubt, eagerly urged on the one part and as eagerly repelled on the other. The chemical school was now divided according to these opposite opinions, and each party in their writings sought to give weight to what they taught by borrowing in support of their arguments the names of the mighty dead. In this conflict it was left to the followers of Rases to sustain the affirmative and to assert the possibility of transmutation. These were the apologists for the past, and the advocates, in the name of their great master, of that hope which had inspired previous research and borne fruit in so many important discoveries.

The defence of the new doubt belonged on the other hand to the school of Al Kindi. This chemist lived and died during the ninth century. He was probably the earliest Arabian commentator on Aristotle, and seems to have paid special attention to the Meteora of that author. The treatise De Mineralibus, so often appended to the Meteora as a supplement, is ascribed to Al Kindi in the Paris manuscript.[114] It represents the alchemy of the time.

Between these two contending parties stood the school of Avicenna, which now occupied an intermediate position and doubted of the doubt. That this had not always been the opinion of Avicenna himself is plain, however, from a passage which occurs in his Sermo de generatione lapidum, where the author unhesitatingly pronounces against the theory of transmutation. ‘Those of the chemical craft,’ he says, ‘know well that no change can be effected in the different species of things, though they can produce the appearance of them: tinging that which is ruddy with yellow till it looks like gold, and that which is white with colour at their pleasure till the same effect is in great measure produced. Nay, they can also remove the impurity from lead, so that it looks like silver, though it be lead still, and can endue it with such strange qualities as to deceive men’s senses, and this by the use of salt and sal ammoniac.’[115] Avicenna was evidently well acquainted with the secrets of art and held them at their proper value. Had his followers in the eleventh century done the same they would have supported the school of Al Kindi instead of taking a less definite position.

This view of the later Arabian schools and their differences is forced upon us by the fact, that works are extant under the names of Rases, Al Kindi, and Avicenna, which evidently belong to the eleventh century, the period when they first appeared, and could not therefore have been written by authors who lived at an earlier date. They are plainly the production of later chemists who followed more or less intelligently the doctrine of these great masters in alchemy. The artifice involved in this ascription of authorship is one which has always been common in Eastern literature.

We have a direct interest in observing that Spain was the country where these developments of the later Arabian chemistry arose, contended and flourished. Spain, therefore, during the eleventh and twelfth centuries, became, by the attraction she offered to European scholars, the country where these theories first reached the Latin races, and began to find an entrance among them. M. Berthelot indeed, by a happy citation, has enabled us to fix, almost with certainty, the very moment of this important event. Robert Castrensis, the author alluded to, remarks: ‘Your Latin world has not as yet learned the doctrine of Alchemy.’ These words are taken from the preface to this author’s version of the Liber de Compositione Alchimiae, and a colophon informs us that the translation was completed on the 11th of February 1182. We may add that the same year, corrected, however, in one copy to 1183, was the date of another of these versions of the Arabian chemistry: that of the treatise called Interrogationes Regis Kalid, et responsiones Morieni.[116] Here then we stand on the threshold of a new age, and find ourselves in presence of an intellectual movement which was certainly of the greatest importance, since in it we may trace the origin of our modern chemistry. The knowledge of what had already been gained by Greek and Arabian alchemists was the first step to independent research among the Latins. The closing years of the twelfth century saw that knowledge at last beginning to unfold itself in a form intelligible to the Western schools.

As in Bagdad during the ninth century, the palmy period of Syrian studies, so in Spain three hundred years later, the work was in its commencement essentially one of interpretation, and the first age of these labours was distinguished by the number of versions which were then produced. From 1182, through the whole of the following century, students laboured in the translation of Moorish books on chemistry. Only towards the close of this period did a tendency become apparent which led in the direction of improvement and innovation. The seed already sown had begun to bear fruit. The material thus derived from Eastern sources was now treated with a new freedom, enriched by the results of original experiment, and edited in forms which betray the influence of scholastic philosophy. The criticism, however, which would determine the precise point when this change began to be operative, and the extent to which it proceeded, attempts what is perhaps an impossible and certainly a difficult task. For it is a remarkable fact that no Arabic texts have been preserved to us which can be regarded as the originals from which these earlier Latin versions were made. This want is probably due to the widespread destruction which overtook the Moorish libraries of Spain.[117] That such originals did at one time exist, however, is made certain by the correspondence which the Latin translations show with those which have come down to us in another language, the Hebrew. The labours of these Latin translators during a hundred years may be found in the manifold collections of chemical treatises, containing some forty or fifty articles apiece, which were arranged and copied out at the beginning of the fourteenth century. These volumes became, after the invention of printing, the chief quarry whence were composed the Ars Aurifera; the Theatrum Chemicum of Zetzner, and the Bibliotheca of Manget.

We are now in a position to understand, not only the nature and progress of the work in which Michael Scot took part, but the exact development which alchemy had reached in his day, and therefore the relation which his chemical publications bore to the general direction of study in this department of science. The time and care which our survey of the field has demanded need not be thought ill spent. It has prepared the way for a more intelligent appreciation of Scot’s labours as a chemist, and has furnished us with the means of coming to a true judgment regarding their authenticity and value.