Circulation of the Blood 125 



the heart on the one hand, therefore, the blood 

 speedily returns to it again ; another and longer circula- 

 tion proceeding from the left ventricle of the heart 

 performs the circuit of the whole body by the arteries, 

 and by the veins returns to the right side of the heart." 



The learned anatomist might here have added a third 

 and extremely short circulation, viz. from the left to the 

 right ventricle of the heart, with that blood which 

 courses through the coronary arteries and veins, and by 

 their ramifications is distributed to the body, walls, and 

 septum of the heart. 



" He who admits one circulation," proceeds our 

 author, " cannot repudiate the other ; " and he might, 

 as it appears, have added, " the third." For why 

 should the coronary arteries of the heart pulsate, if it 

 were not to force on the blood by their pulsations ? 

 and why should there be coronary veins, the end and 

 office of all veins being to receive the blood brought by 

 the arteries, were it not to deliver and discharge the 

 blood sent into the substance of the heart? In this 

 consideration let it be remembered that a valve is very 

 commonly found at the orifice of the coronary vein, 

 as our learned author himself admits, 1 preventing all 

 ingress, but offering no obstacle to the egress of the 

 blood. It therefore seems that he cannot do otherwise 

 than admit this third circulation, who acknowledges a 

 general circulation through the body, and that the 

 blood also passes through the lungs and the brain. 2 

 Nor, indeed, can he deny a similar circulation to every 

 other part of every other region. The blood flowing 

 in under the influence of the arterial pulse, and returning 

 by the veins, every particle of the body has its 

 circulation. 



From the words of our learned writer quoted above, 

 consequently, his opinion may be gathered both of the 

 general circulation, and then of the circulation through 

 the lungs and the several parts of the body ; for he who 



1 Lib. iii, cap. 9. 2 Lib. iv, cap. 2. 



