MOTION OF THE HEART AND BLOOD 



heart, the artery leaves at the upper. Now, pinch- 

 ing off the vena cava with a forceps or between 

 finger and thumb, the course of blood being inter- 

 cepted some distance below the heart, you will 

 see that the space between the finger and the heart 

 is drained at once, the blood being emptied by the 

 heart beat. At the same time, the heart becomes 

 much paler even in distention, smaller from lack 

 of blood, and beats more slowly, so that it seems 

 to be dying. Immediately on releasing the vein, 

 the color and size of the heart returns to normal. 



On the other hand, leaving the vein alone, if you 

 ligate or compress the artery a little distance above 

 the heart, you will see the space between the com- 

 pression and the heart, and the latter also, become 

 greatly distended and very turgid, of a purple or 

 livid color, and, choked by the blood, it will seem to 

 suffocate. On removing the block, the normal 

 color, size, and pulse returns. 



This is evidence of two kinds of death, failure 

 from a lack, and suffocation from excess. In these 

 examples of both, one may find proof before his 

 eyes of the truth spoken about the heart. 



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