SCOPE AND AIMS 17 



essence be identical, or at all events similar, 

 but this is doubtful. 



6. The laws of physics are applied by the 

 physiologist to the investigation of the 

 motions of the solids and fluids in the animal 

 organism. Thus the movements of the limbs 

 in locomotion are mechanical, the movements 

 of the blood in the circulation are subject to 

 the physical laws of hydrodynamics, the 

 interchanges of gases between the air and 

 the blood in respiration are to be explained 

 as special cases of the transfusion of gases 

 through thin membranes, while the actions 

 of the eye and ear can only be understood 

 by the study of optics and acoustics and 

 their application to these highly specialized 

 mechanisms. The absorption into the blood 

 of nutrient matters, after their preparation by 

 digestion, and the elimination of waste matters 

 from the blood by various organs, are so far 

 to be explained by the laws regulating the 

 passage of fluids through thin membranes, 

 and which are studied by the physicist. 

 It may indeed be said that physical processes 

 are more or less involved in all the phenomena 

 B 



