8o THE HISTORY OF BIOLOGY 



combinations of metals; he also introduced into chemical terminology the 

 word "affinity" as denoting chemical relationship. As a biologist he follows 

 Aristotle, even where the latter's errors have been corrected by other ancient 

 philosophers; he holds that the arteries contain air, that the brain is humid 

 and cold, etc. The observations which he himself claims to have made are 

 often purely fantastical, but they also sometimes bear witness to his powers 

 of observation, which his chemical researches prove him to have possessed 

 in a high degree. His greatest service undoubtedly lies in his having directed 

 the world's attention to Aristotle's conception of nature and thereby also 

 indirectly evoking an interest in nature itself — an interest which the suc- 

 ceeding centuries were able to cherish and widen. 



Contemporary with Albertus and, like him, a Dominican friar was 

 Thomas, called Cantimpratensis, after the monastery atCantimpre in France, 

 where he worked. His home was at Liege, but he studied at Cologne and 

 finally became a canon in the afore-mentioned monastery. His principal 

 work, De naturis rermn, forms, like that of his master, a compilation of the 

 nature theories of Aristotle and other classical authors, with a wealth of 

 notes on animals, both real and imaginary. More than Albertus, Thomas has 

 a penchant for weaving into his accounts of animals stories with a moral 

 point to them, and also, on the whole, he enters more into detail and is 

 less systematic than his master. 



A third contemporary of these two, and a brother monk, was Vincen- 

 Tius Bellovacensis, who was likewise named after his monastery, at Beau- 

 vais in France. He wrote a work on nature entitled Speculum natura — 

 Nature's Mirror. This work is compiled from various sources: Aristotle in 

 Latin translation, Pliny, and Avicenna, as well as the Bible and the Church 

 Fathers. Though more haphazard and less lucidly arranged than those of 

 his colleagues mentioned above, it nevertheless had its influence on the age 

 and the succeeding centuries. 



It is not worth while recounting further examples of this kind of medi- 

 aeval descriptions of nature — natural research it can scarcely be called. Those 

 already cited sufficiently show their character, that of a compilation of the 

 literary material of past ages in the service of that stock conservative theol- 

 ogy which dominated science during these centuries. But even at this period 

 there arose personalities whose ideas presage the intellectual liberation, the 

 foundations of which were laid in the course of these centuries and which 

 was destined later to overcome all obstacles during the Renaissance. One 

 such man was Roger Bacon (born 1114, died 12.94). By birth an Englishman, 

 he studied at Oxford and Paris and entered the Franciscan order, in which 

 he soon assumed a position of eminence. His liberal views, however, gained 

 for him bitter enemies, and once he was arrested and had to spend years in 

 prison, being deprived of every possibility of working until he was again 



