WORKING OF THE HEART AND BLOOD-VESSELS. 239 



thus on two factors: first, the elasticity of the large arteries; 

 and, secondly, the resistance to their emptying, dependent 

 upon internal friction in the small arteries and the capillaries, 

 which calls into play the elasticity of the large vessels. Were 

 the capillary resistance or the arterial elasticity absent the 

 blood-flow in the capillaries would be rhythmic. 



