34 CIRCULATION OF THE BLOOD 



take place, as is generally believed, through the septum of 

 the heart, but by a remarkable device the subtle blood is 

 driven from the right ventricle through a long passage in the 

 lungs. It is prepared by the lungs, and is there rendered 

 lighter in colour, and from the artery-like vein [pul- 

 monary artery] it is poured into the vein-like artery 

 [pulmonary vein]. Then in the vein- like artery [pul- 

 monary vein] it is mixed with the inspired air, and by 

 expiration is cleansed from its fumes. So at length 

 completely mingled [with the air] it is drawn in by the 

 left ventricle during its expansion, ready to become vital 

 spirit." Would it be possible to describe the pulmonary 

 circulation better in so few words ? 



That the communication and preparation," he adds, 

 " does take place in this way through the lungs [and not 

 through the septum] is moreover shown by the manifold 

 conjunction and communication of the arterial vein 

 [pulmonary artery] with the venal artery [pulmonary 

 vein] in the substance of the lung. This is confirmed 

 by the remarkable size of the venal artery [pulmonary 

 vein], which would not have been made so large and would 

 not discharge from the heart itself such a mass of pure 

 blood into the lungs merely for nourishment." This is 

 the first clear account of the lesser circulation. But can 

 we call it a real discovery ? Hardly. Servetus was so 

 near and yet so far from being a great physiologist ! But 

 he tells us something of the physiological questions of 

 his day, and he shows us how the world was, as it were, 

 almost consciously awaiting a solution of the ancient 

 problem. 



Let us follow a little further the career of the man who 

 wrote this. After he left Paris, Servetus spent a good 

 deal of his time in practice as a physician at Vienne in 

 south-eastern France. In 1546, the year of the completion 

 of his work on the Restitution of Christianity, he opened 



