HIS WORKS. Ivii 



the right ventricle of the heart communicates to the left. But 

 this communication takes place, not by the middle septum of 

 the heart, as is commonly believed, but by a remarkable arti- 

 fice ; the subtile blood of the right side of the heart is agitated 

 in a lengthened course through the lungs, whereby it is elabo- 

 rated, from which it is thrown of a crimson colour, and from 

 the vena arteriosa (pulmonary artery) is transfused into the 

 arteria venosa (pulmonary veins) ; it is then mixed in the 

 arteria venosa itself with the inspired air, and by the act of 

 expiration is purified from fuliginous vapours, when, having 

 become the fit recipient of the vital spirit, it is at length 

 attracted by the diastole. Now, that the communication and 

 preparation take place as stated through the lungs, is pro- 

 claimed by the various conjunctions and communications of 

 the arterial vein with the venous artery. The remarkable 

 size of the arterial vein (pulmonary artery) confirms this, a 

 vessel which could neither have its actual constitution nor 

 dimensions, nor transmit such a quantity of the purest blood 

 direct from the heart itself, for the mere nourishment of the 

 lungs. Neither would the heart supply the lungs in such 

 proportion, (especially when we see the lungs in the embryo 

 nourished from another source) by reason of those membranes or 

 valves which remain unopened until the hour of birth, as 

 Galen teaches. The blood, consequently, from the moment of 

 birth, is sent, and in such quantity is sent, for another pur- 

 pose from the heart into the lungs; from the lungs also it is 

 not simple air that is sent to the heart, but air mixed with 

 blood is transmitted through the arteria venosa (pulmonary 

 vein) . In the lungs consequently does the mixture take place. 

 The crimson colour is imparted to the spirituous blood by the 

 lungs, not by the heart. There is not room enough in the 

 left ventricle of the heart for so important and so great an 

 admixture; neither is there space there for the elaboration 

 into the crimson colour. Finally, the septum medium, seeing 



