8 WHAT THE STUDY OF PHYSIOLOGY MEANS 



order to answer the question " how " we should first pull 

 our pump or a similar machine to pieces and find what 

 parts it has and how they are placed in relation to one 

 another. We should call this the study of the structure 

 of the pump. Next, we should set the machine in motion 

 and observe the action of the parts and how the move- 

 ment of one affects the other. We should call this the 

 study of function, or use of parts. Combining our knowl- 

 edge of structure and function we might go still further, 

 and, by experimenting, find that certain actions, such as 

 lubricating the parts with oil, improve the action of the 

 machine as a whole. We call this the study of the con- 

 ditions best suited to the action of the machine. 



Applied to the study of living objects such a method of 

 investigation resolves itself into the following divisions of 

 research. 



First. The study of the structure of the living bodies. 

 Such a study is called anatomy (ana, up; temnein, to cut) 

 and is dependent upon dissection. 



Second. The study of the use or functions of the various 

 structures. Such a study is called physiology {jphysiologia, 

 an investigation into the nature of things) and is dependent 

 upon experimenting w'lih. living structures. 



Third. The study of methods that will cause the parts 

 to act to the best advantage. This study is called hygiene 

 {hygeia, health) and like physiology is dependent upon 

 experimentation. 



Formulating these three directions we have the follow- 

 ing definitions : 



Anatotiy. — The study of the structure of a plant or 

 animal to determine the parts present and the relative 

 position of these parts. 



