74 THE LIFE AND LEGEND OF MICHAEL SCOT 



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 eflPect is in great measure pro- 

 duced. Nay, they can also remove the impurity 

 from lead, so that it looks like silver, thouo-h 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' ^ 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 theu" 

 differences is forced upon us by the fact, that works 

 are extant under the names of Kases, Al Kindi, and 

 Avicenna, which evidently belong to the eleventh 

 century, the period when they first appeared, and 

 could not therefore have been written bv 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 observinof that 

 Spain was the country where these developments 



^ Fondo Vaticano, 4428, p. 114. This treatise is tlie same as the De 

 mineralibus published along with the I)e Secretis id Venice (? 1501) by 

 Bernardiniis de Vitalibiis. 



