452 THE POPULAR SCIENCE MONTHLY 



This catalogue of Albertus Magnus's works shows very well his own 

 interest and that of his generation in physical science of all kinds. 

 There were eight treatises on Aristotle's physics and on the underlying 

 principles of natural philosophy and of energy and of movement; four 

 treatises concerning the heavens and the earth, one on physical geog- 

 raphy which also contains, according to Pagel, numerous suggestions 

 on ethnography and physiology. There are two treatises on generation 

 and corruption, six books on meteors, five books on minerals, three 

 books on the soul, two books on the intellect, a treatise on nutritives, 

 and then a treatise on the senses and another on the memory and on 

 the imagination. All the phases of the biological sciences were espe- 

 cially favorite subjects of his study. There is a treatise on the motion 

 of animals, a treatise in six books on vegetables and plants, a treatise 

 on breathing things, a treatise on sleep and waking, a treatise on youth 

 and old age and a treatise on life and death. His treatise on minerals 

 contains, according to Pagel, a description of ninety-five different kinds 

 of precious stones. Albert's volumes on plants were reproduced with 

 Meyer, the German botanist, as editor (Berlin, 1867). All of Albert's 

 books are available in modern editions. 



Pagel says of Albertus Magnus that 



His profoiind scholarship, his boundless industry, the almost incontrollable 

 impulse of his mind after universality of knoweldge, the many-sidedness of hia 

 literary productivity, and finally the almost universal recognition which he 

 received from his contemporaries and succeeding generations, stamp him as one 

 of the most imposing characters and one of the most wonderful phenomena of 

 the middle ages. 



In another passage Pagel has said : 



While Albert was a Churchman and an ardent devotee of Aristotle, in 

 matters of natural phenomena he was relatively unprejudiced and presented an 

 open mind. He thought that he must follow Hippocrates and Galen, rather 

 than Aristotle and Augustine, in medicine and in the natural sciences. We 

 must concede it a special subject of praise for Albert tliat he distinguished 

 very strictly between natural and supernatural phenomena. The former he 

 considered as entirely the object of the investigation of nature. The latter he 

 handed over to the realm of metaphysics. 



Roger Bacon is, however, the one of these three great teachers 

 who shows us how thoroughly practical was the scientific knowledge of 

 the universities and how much it led to important useful discoveries 

 in applied science and to anticipations of what is most novel even in 

 our present-day sciences. Some of these indeed are so startling, that 

 only that we know them not by tradition but from his works, where 

 they may be readily found without any doubt of their authenticity, we 

 should be sure to think that they must be the result of later com- 

 mentators' ideas. Bacon was very much interested in astronomy, and 

 not only suggested the correction of the calendar, but also a method by 



