To give a substantial idea of the De Alchimia let us translate one of the formulae which it contains: ‘Medibibaz the Saracen of Africa used to change lead into gold [in the following manner]. Take lead and melt it thrice with caustic (‘comburenti’), red arsenic, sublimate of vitriol, sugar of alum, and with that red tuchia of India which is found on the shore of the Red Sea, and let the whole be again and again quenched in the juice of the Portulaca marina, the wild cucumber, a solution of sal ammoniac, and the urine of a young badger. Let all these ingredients then, when well mixed, be set on the fire, with the addition of some common salt, and well boiled until they be reduced to one-third of their original bulk, when you must proceed to distil them with care. Then take the marchasite of gold, prepared talc, roots of coral, some carcha-root, which is an herb very like the Portulaca marina; alum of cumae something red and saltish, Roman alum and vitriol, and let the latter be made red; sugar of alum, Cyprus earth, some of the red Barbary earth, for that gives a good colour; Cumaean earth of the red sort, African tuchia, which is a stone of variegated colours and being melted with copper changeth it into gold; Cumaean salt which is …; pure red arsenic, the blood of a ruddy man, red tartar, gumma of Barbary, which is red and worketh wonders in this art; salt of Sardinia which is like …. Let all these be beaten together in a brazen mortar, then sifted finely and made into a paste with the above water. Dry this paste, and again rub it fine on the marble slab. Then take the lead you have prepared as directed above, and melt it together with the powder, adding some red alum and some more of the various salts. This alum is found about Aleppo (‘Alapia’), and in Armenia, and will give your metal a good colour. When you have so done you shall see the lead changed into the finest gold, as good as what comes from Arabia. This have I, Michael Scot, often put to the proof and ever found it to be true.’
If such a receipt is valuable as indicating the chemical practice of those days, it is no less interesting as it throws light upon the life and occupations of Scot. He must have set up a complete chemical laboratory at Toledo, with crucibles for the melting of metals, and alembics for the distillation of the substances which his art required him to mix with them. His situation was one very favourable to these pursuits, not only because Spain was one of those countries where the doctrine of alchemy made its greatest progress, and attracted most powerfully the concourse of foreign adepts, but also from the facility with which the necessary materia chemica could there be procured. The sierras of that country were full of mineral wealth of all kinds, especially quicksilver, which was one of the substances most frequently chosen to become the subject of the transmuter’s art. In the Alpujarras, a mountainous district lying under the soft climate of Granada, grew plenty of these rare herbs employed in alchemy, as they were also in the medicine of the Arabians. Ibn Beithar of Malaga describes them in his botanical thesaurus, and it is said that after the Moors had lost that fair kingdom their herbalists, even as late as our own times, made yearly journeys from Africa to gather in these hills the plants which ancient science taught them to value highly. But the days of the ‘ultimo sospiro del Moro’ were yet in the far future, and meanwhile Michael Scot in his laboratory at Toledo could easily command all these treasures for the purposes of experiment. Nor was it in vain that he fanned his fires, and watched the metals melt and the menstruum distil in the process of the lesser or greater mystery. If he never saw Venus blush into the true substance of Sol, or Mercury, the fickle and obstinate, congeal into a veritable Luna, his chemical practice, and the records in which he has embodied it, mark none the less true and significant a moment in the history of scientific progress.
CHAPTER V
THE ASTRONOMICAL WRITINGS OF SCOT
The alchemy of the thirteenth century, to the progress of which Michael Scot contributed not a little, bore a close relation to the opinions then entertained in another branch of science: that of astronomy. We have already noticed how chemistry, as practised in Egypt, was largely influenced by Eastern theories regarding the stars and their power over earthly elements. That this connection and sympathy was still a matter of common belief at the time Scot wrote is not only probable but can readily be established by direct evidence. The treatise ‘Cum studii solertis indagine,’ already referred to,[142] has a curious passage which bears directly on the point in question. We find in the preface the following remarkable statement: ‘For the art of alchemy belongs to the deeper and more hidden physics, and in particular to that division thereof which … is called the lower astronomy,’ It is plain then that no chemist could in those days be considered fully competent for the task he undertook unless to a knowledge of the customary theories and processes of his art he added some acquaintance with the mysteries of the heavenly spheres as well.
To Michael Scot, even before he came to Toledo, the science of astronomy was already a beaten path. His progress in mathematical studies naturally led him to this, the highest sphere in which they could be exercised. At the court of Frederick he had made many an observation and cast many a horoscope. In the Liber Introductorius and Liber Particularis he had produced two manuals expounding in a popular way the twin sciences of astrology and astronomy; publications which no doubt reproduced pretty exactly the teaching he had given to the Emperor.
In Spain he not only kept up his interest in this subject but lost no opportunity of improving his past acquirements. He was constantly on the watch for new astronomical works. He read them, not only as a student eager to extend his knowledge, but as a translator anxious to find the opportunity of adding to the resources of other scholars by the production of some important book in a Latin dress.
As a resident in Toledo, Scot found himself very favourably situated for such studies. That city was now indeed to become what may be called the classic ground of Moorish astronomy. A Spanish author would have us believe that there presently assembled there an incredible number of astronomers drawn, not only from all parts of Spain, but from France as well, and especially from Paris. The king himself is said to have presided over this congress. The works of Ptolemy, with the commentaries of Montafan and Algazel, were translated into Latin for the use of those scholars who did not understand Arabic. Discussions were held in the Alcazar of Galiana upon the various theories of the heavenly bodies and their movements. These labours, which commenced in 1218, and are said to have lasted till 1262, resulted in a more exact series of observations than had hitherto been made. They were published, and became generally known as the Tables of Toledo.[143]
It was in such a direction indeed that the line of true progress lay. As alchemy rose into a real chemistry rather by the practice of the laboratory than by the theory of the schools, so it was with regard to astronomy. The scheme of Ptolemy with its various modifications necessarily held the field, imperfect and erroneous as it was, till wider and more exact observations, such as those for which the wise king of Castile thus provided had, in the course of after ages, furnished adequate ground for the magical and illuminative speculations of Copernicus, Galileo, and Newton.