200 ANIMAL AUTOMATISM. [LECT. 



If we ask to whom mankind are indebted for this 

 great service, the general voice will name William 

 Harvey. For, by his discovery of the circulation of the 

 blood in the higher animals, by his explanation of the 

 nature of the mechanism by which that circulation is 

 effected, and by his no less remarkable, though less 

 known, investigations of the process of development, 

 Harvey solidly laid the foundations of all those 

 physical explanations of the functions of sustentation 

 and reproduction which modern physiologists have 

 achieved. 



But the living body is not only sustained and 

 reproduced : it adjusts itself to external and internal 

 changes ; it moves and feels. The attempt to reduce 

 the endless complexities of animal motion and feeling 

 to law and order is, at least, as important a part of 

 the task of the physiologist as the elucidation of what 

 are sometimes called the vegetative processes. Har- 

 vey did not make this attempt himself; but the 

 influence of his work upon the man who did make it 

 is patent and unquestionable. This man was Kene 

 Descartes, who, though by many years Harvey's 

 junior, died before him ; and yet, in his short span of 

 fifty-four years, took an undisputed place, not only 

 among the chiefs of philosophy, but amongst the 

 greatest and most original of mathematicians ; while, 

 in my belief, he is no less certainly entitled to the 

 rank of a great and original physiologist ; inasmuch as 

 he did for the physiology of motion and sensation 

 that which Harvey had done for the circulation of 

 the blood, and opened up that road to the mechanical 



