FURNITURE, AND ITS USES. 225 



pushes the blood with considerable force ; and 

 the muscular capillaries, at the same time, act 

 in a slight degree like little pumps. Then the 

 vacuum I have spoken of has some influence ; 

 and there may be other causes in operation 

 which I have not mentioned. The whole 

 process of circulation is wonderful, and it 

 requires a large volume to illustrate and ex- 

 plain it fully. 



