CHAPTER XI 



THE SECOND POSITION IS DEMONSTRATED 



THAT this may the more clearly appear to every one, 

 I have here to cite certain experiments, 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 immediately 

 by anastomosis from the arteries into the veins, or 

 mediately 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 mani- 

 fest that in the circuit the blood moves from thence 

 hither, and from hence thither ; from the centre to the 

 extremities, to wit ; and from the extreme parts back 

 again to the centre. Finally, upon grounds of calcula- 

 tion, with the same elements as before, it will be 

 obvious that the quantity can neither be accounted 

 for by the ingesta, nor yet be held necessary to 

 nutrition. 



The same thing will also appear in regard to ligatures, 

 and wherefore they are said to draw; though this is 

 neither from the heat, nor the pain, nor the vacuum 

 they occasion, nor indeed from any other cause yet 

 thought of; it will also explain the uses and advantages 

 to be derived from ligatures in medicine, the principle 

 upon which they either suppress or occasion hemor- 

 rhage ; how they induce sloughing and more extensive 



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