70 THE LIFE OF SCIENCE 



curiosity was universal to such a degree that to write a complete 

 study of his genius amounts to writing a real encyclopaedia of 

 fifteenth-century science and technology. From his earliest age he 

 had given proofs of this insatiable thirst for knowledge. He could 

 take nothing for granted. Everything that he saw, either in the 

 fields or on the moving surface of a river, or in the sky, or in the 

 bottega of his master, or in the workshops of Florence, raised a 

 new problem in his mind. Most of the time neither man nor book 

 could give an answer to his question, and his mind kept working 

 on it and remained restless until he had devised one himself. This 

 means, of course, that there was no rest for him until the end. In 

 a few cases, however, a satisfactory answer suggested itself, and 

 so a v/hole system of knowledge was slowly unfolding in him. 



His apprenticeship in Verrocchio's studio must have greatly 

 fostered his inquiries in the theory of perspective, the art of light 

 and shade, and the physiology of vision; the preparation of colors 

 and varnishes must have turned his thoughts to chemistry; while 

 the routine of his work woke up naturally enough his interest in 

 anatomy. He could not long be satisfied by the study of the so- 

 called artistic anatomy, which deals only with the exterior 

 muscles. For one thing, the study of the movements of the human 

 figure, which he tried to express in his drawings, raised innumer- 

 able questions: how were they possible, what kept the human 

 machine moving and how did it work? ... It is easy to 

 imagine how he was irresistibly driven step by step to investigate 

 every anatomical and physiological problem. There are in the 

 King's library at Windsor hundreds of drawings of his which 

 prove that he made a thorough analysis of practically all the 

 organs. Indeed, he had dissected quite a number of bodies, in- 

 cluding that of a gravid woman, and his minute and compre- 

 hensive sketches are the first anatomical drawings worthy of the 

 name. Many of these sketches are devoted to the comparison of 

 human anatomy with the anatomy of animals, the monkey or the 

 horse for instance; or else he will compare similar parts of various 

 animals, say, the eyes or a leg and a wing. Other sketches relate 



