" What is the range and position of Physiological Science as a 

 branch of knowledge, and what is its value as a means of mental 

 discipline ? Its subject-matter is a large moiety of the universe ; 

 its position is midway between the physico-chemical and the social 

 sciences. Its value as a branch of discipline is partly that which it 

 has in common with all sciences the training and strengthening 

 of common sense ; partly that which is more peculiar to itself the 

 great exercise which it affords to the faculties of observation and 

 comparison ; and, I may add, the exactness of knowledge which it 

 requires on the part of those among its votaries who desire to extend 

 its boundaries." HUXLEY. 



" The great benefit which a scientific education bestows, whether 

 as training or as knowledge, is dependent upon the extent to which 

 the mind of the student is brought into immediate contact with 

 facts upon the degree to which he learns the habit of appealing 

 directly to Nature, and of acquiring through his senses concrete 

 images of those properties of things which are, and always will be, 

 but approximative^ expressed in human language." HUXLEY 



viii 



