Chapter V 

 The Actions and Functions of the Heart 



FROM these and other observations I am con- 

 vinced that the motion of the heart is as follows: 

 First, the auricle contracts, and this forces the 

 abundant blood it contains as the cistern and reser- 

 voir of the veins, into the ventricle. This being 

 filled, the heart raises itself, makes its fibers tense, 

 contracts, and beats. By this beat it at once ejects 

 into the arteries the blood received from the auricle; 

 the right ventricle sending its blood to the lungs 

 through the vessel called the vena arteriosa, but 

 which in structure and function is an artery; the 

 left ventricle sending its blood to the aorta, and to 

 the rest of the body through the arteries. 



These two motions, one of the auricles, the other 

 of the ventricles, are consecutive, with a rhythm 

 between them,^ so that only one movement may 



^ The auricular-ventricular rhythm has become an important sub- 

 ject for investigation and discussion since the introduction of electro- 

 cardiographic studies by means of W. Einthoven's (i86o-i9a7) string 

 galvanometer. See F. H. Garrison's History of Medicine, 3rd Ed., 

 Phila., I92i,p. 735. 



Note the excellent description of the chain of events in the act of 

 swallowing. Here is an example of that straight-forward mechanistic 

 description of functional activity in which Harvey so closely approxi- 



I47] 



