MOTION OF THE HEART AND BLOOD 



no one need doubt further, for if the cavity of the 

 ventricle be cut into, the blood contained therein 

 will be forcibly squirted out when the heart is tense 

 with each movement or beat. 



The following things take place, then, simul- 

 taneously: the contraction of the heart; the beat 

 at the apex against the chest, which may be felt 

 outside; the thickening of the walls; and the forcible 

 ejection of the blood it contains by the constriction 

 of the ventricles. 



So the opposite of the commonly received opinion 

 seems true. Instead of the heart opening its ven- 

 tricles and filling with blood at the moment it strikes 

 the chest and its beat is felt on the outside, the 

 contrary takes place so that the heart while con- 

 tracting empties. Therefore the motion commonly 

 thought the diastole of the heart is really the systole, 

 and the significant movement of the heart is not the 

 diastole but the systole. The heart does not act 

 in diastole but in systole for only when it contracts 

 is it active. 



It is not to be admitted that the heart moves only 

 in the direction of its straight fibers. The great 

 Vesalius, in support of this idea, speaks of a bundle 

 of willow-twigs bound in a pyramid.'' It is implied 

 that as the apex is drawn to the base, the sides 



''Andreas Vesalius (1514-1564), De Humani Corporis Fabrica, 

 Basle, 1543, Lib. 6, Cap. zo, p. 587. It is interesting to note how 

 Vesalius described fairly well the gross structures of the heart, and then 

 fitted them as best he could into the Galenical system. 



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