128 THE ADVANCE OF SCIENCE 



functions of assimilation, respiration, se- 

 cretion, distribution of nutriment, removal 

 of waste products, motion, sensation, and 

 reproduction are performed ; while the 

 operation of the nervous system, as a 

 regulative apparatus, which influences the 

 origination and the transmission of mani- 

 festations of activity, either within itself 

 or in other organs, has been largely eluci- 

 dated. 

 Practi- I have pointed out, in an earlier part 



of physi- of this chapter, that the history of all 

 discov- branches of science proves that they must 

 ery " attain a considerable stage of development 

 before they yield practical ' fruits ; ' and 

 this is eminently true of physiology. It 

 is only within the present epoch, that 

 physiology and chemistry have reached 

 the point at which they could offer a sci- 

 entific foundation to agriculture ; and it 

 is only within the present epoch, that 

 zoology and physiology have yielded any 

 very great aid to pathology and hygiene. 



