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SCIENCE 



[N. S. Vol. XLIV. No. 1127 



of the circulation Harvey naturally reviewed 

 what little was known of the respiration in re- 

 gard to which there were current at this time 

 two ancient beliefs, (1) the refrigerating ac- 

 tion and (2) the production of vital spirits. 

 The Hippocratic writers believed that in spite 

 of the obstruction of the semilunar valves 

 some air entered the heart to cool it. Aristotle 

 amplified this view, stating that the action of 

 the air upon the innate heat which had as its 

 origin and seat the heart, was like the action 

 of the air in respect to a fire — it cooled it and 

 prevented too rapid combustion. The second 

 conception was also as old as Hippocrates. It 

 consisted in the belief that something derived 

 from the inspired air (spirits) enters into the 

 heart and thence passes by the vessels to all parts 

 of the body. Aristotle rejected this doctrine 

 and taught that the spirits are not derived from 

 without. When the arteries and veins came 

 to be distinguished and the former were found 

 empty, it was thought that during life the 

 spirits filled the arteries while the blood filled 

 the veins, and when Galen proved that the 

 arteries also contained blood it was at once 

 concluded that this blood, unlike that in the 

 veins, was spirituous. 



For a while Harvey held both of these views. 

 Then first he disposed of the notion that the 

 blood received anything from the lungs by ob- 

 serving that the pulmonary veins contain blood 

 only and not blood and air. This conclusion 

 was not justified, since from the same premises 

 Columbus inferred that the concoction of the 

 air and blood to make the spirituous blood 

 takes place in the lungs and that in the pulmon- 

 ary veins the two are no longer separable. For 

 a longer time Harvey adhered to the refrig- 

 erating action of the respiration, but in his old 

 age he was inclined to doubt its importance, 

 for the fetus required no refrigeration of its 

 innate heat. So it was of no use to turn to 

 the respiration for any light as to the uses of 

 the circulation. 



Primacy of the Heart. — But might it not be 

 that the body needed heat and spirits from 

 the heart which is, according to Aristotle, the 

 center of heat and of the soul? Aristotle's 

 doctrine of the primacy of heat had been de- 



nied by Galen who pointed to the tricuspid 

 valve (of which Aristotle knew nothing) and 

 asked : " How then can the heat be the origin 

 of the veins ? " According to Galen the veins 

 arose from the liver and supplied the parts 

 with nutritive blood. The heart, on the other 

 hand, supplied the parts with spirituous blood. 

 The little blood which passed from the right 

 to the left side of the heart did so through in- 

 visible pores of the septum. In the left ven- 

 tricle it became mixed with spirits and passed 

 thence to the aorta and also to the lungs 

 through the mitral valve, which, having but 

 two leaves, was imperfect. The followers of 

 Aristotle (called " philosophers ") and those 

 of Galen (" physicians ") were soon at odds, 

 each finding the weak points of the other's 

 doctrine. In Galenism were the pores in the 

 septum and the imperfection of the mitral 

 valve; while, on the other hand, the tricuspid 

 was the stumbling block of the Aristotelians. 



By his discovery of the pulmonary path for 

 the blood Columbus materially aided the 

 Galenists, who might now abandon the idea 

 that blood sweats through pores in the septum. 

 "When Harvey demonstrated the circulation 

 and thus explained the use of the atrio- 

 ventricular valves, he regarded himself as 

 defending Aristotle's doctrine of the primacy 

 of the heart and hence his remark regarding 

 his opponent Riolanus, " It is proper that the 

 dean of the College of Paris should keep the 

 medicine of Galen in repair ; and should admit 

 no novelties into his school without the utmost 

 winnowing." 



Primacy of the Blood. — Aristotle believed 

 that the heart was the center of life, the source 

 of heat and the abode of the soul. But to the 

 discoverer of the circulation the primacy of 

 the heart began very early to give place to the 

 primacy of the blood until in his latest utter- 

 ances the heart is merely the servant of the 

 blood, of use to pump it along but contributing 

 to the blood nothing but motion. Harvey sup- 

 ported this novel view by observation. He be- 

 lieved that he saw in the chick embryo first 

 the blood which presently began to pulsate by 

 itself and only later the developing heart. 



Aristotle had set forth a principle that those 



