CHAPTER X 



THE FIRST POSITION : OF THE QUANTITY OF BLOOD 

 PASSING FROM THE VEINS TO THE ARTERIES. AND 

 THAT THERE IS A CIRCUIT OF THE BLOOD, FREED 

 FROM OBJECTIONS, AND FARTHER CONFIRMED BY 

 EXPERIMENT 



So far our first position is confirmed, whether the 

 thing be referred to calculation or to experiment and 

 dissection, viz. that the blood is incessantly infused 

 into the arteries in larger quantities than it can be 

 supplied by the food ; so that the whole passing over 

 in a short space of time, it is matter of necessity that 

 the blood perform a circuit, that it return to whence it 

 set out. 



But if any one shall here object that a large quantity 

 may pass through and yet no necessity be found for a 

 circulation, that all may come from the meat and drink 

 consumed, and quote as an illustration the abundant 

 supply of milk in the mammae for a cow will give 

 three, four, and even seven gallons and more in a day, 

 and a woman two or three pints whilst nursing a child 

 or twins, which must manifestly be derived from the 

 food consumed ; it may be answered, that the heart by 

 computation does as much and more in the course of 

 an hour or two. 



And if not yet convinced, he shall still insist, that 

 when an artery is divided a preternatural route is, as it 

 were, opened, and that so the blood escapes in torrents, 

 but that the same thing does not happen in the healthy 

 and uninjured body when no outlet is made ; and that 



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