2 92 Mayow 



the septum of the heart. Now, I say, inasmuch as in 

 the contraction of the wall, a^ 3, its one end, b^ that is 

 the cone of the heart, is carried towards c, because of 

 the simultaneous contraction of a^ e^ the septum of 

 the heart, that wall is, in its contraction, carried 

 outwards to d^ and forms the line a^ d^ c, which, 

 although shorter than the line, «, 2, b^ still rises as a 

 tumour at d. The distention of the wall is to no 

 small extent due to the impulse of the blood which, 

 strongly compressed by the contraction of the heart, 

 as it cannot all immediately be driven into the great 

 artery, gives a blow to the wall of the ventricle. 



Should any one ask here how the blood contained 

 within the contracted ventricle, a^ d^ <;, is expelled 

 from it (for it is not to be supposed that in the systole 

 of the heart the ext^reme part of the heart moves 

 quite up to the base of the heart, but that some space 

 remains between them), T answer that it has not yet 

 been established that all the blood leaves the 

 ventricles each time that they contract. And at 

 any rate, if the ventricles of the heart were nearly 

 emptied of blood it would seem that what remains of 

 the blood could not be compressed by them with 

 force sufficient for the projection of the blood to the 

 furthest members of the body. If, however, all the 

 blood is expelled from the ventricles, we must suppose 

 that the walls of the ventricles continue their 

 contraction for some little time after that first rush 

 of the heart by which the pulsation is started. For 

 otherwise it seems impossible that all the blood 

 should be driven by the beat of the heart so 

 instantaneously into the great artery. And it tells 

 in favour of this, that in the section of animals, when 

 the dying heart is opened, the movement of contraction 

 is seen to be completed not at one stroke, but to 



