FROM PARACELSUS TO HARVEY 



that the blood passes from the arteries to the veins. 

 He demonstrated conclusively that this did occur, but 

 for once his rejection of the ancient writers and one 

 modern one was a mistake. For Galen had taught, 

 and had attempted to demonstrate, that there are 

 sets of minute vessels connecting the arteries and the 

 veins; and Servetus had shown that there must be 

 such vessels, at least in the lungs. 



However, the little flaw in the otherwise complete 

 demonstration of Harvey detracts nothing from the 

 main issue at stake. It was for others who followed 

 to show just how these small vessels acted in effecting 

 the transfer of the blood from artery to vein, and the 

 grand general statement that such a transfer does take 

 place was, after all, the all - important one, and the 

 exact method of how it takes place a detail. Harvey's 

 experiments to demonstrate that the blood passes 

 from the arteries to the veins are so simply and con- 

 cisely stated that they may best be given in his own 

 words. 



" I have here to cite certain experiments," he wrote, 

 "from which it seems obvious that the blood enters a 

 limb by the arteries, and returns from it by the veins; 

 that the arteries are the vessels carrying the blood 

 from the heart, and the veins the returning channels 

 of the blood to the heart ; that in the limbs and extreme 

 parts of the body the blood passes either by anastomosis 

 from the arteries into the veins, or immediately by the 

 pores of the flesh, or in both ways, as has already been 

 said in speaking of the passage of the blood through 

 the lungs; whence it appears manifest that in the 

 circuit the blood moves from thence hither, and hence 



