NUTRITION. 



197 



pure the same kind that goes to the brain is sent 

 to the kidneys and to the skin to be purified. Yet, as this 

 mixed blood flows through each organ, that organ, so long 

 as it is in health, takes from it only what it should take 



Lung Capillaries 



Pulmonary Vein 



Body Capillaries 



Fig. 72. Diagram of the Circulation, representing the Right and Left Halves separated 

 (as they are in reality), showing that the Blood makes but One Circuit. 



Action of Diseased Kidneys. The kidney takes, 

 during health, only the waste matters, leaving the valuable 

 nourishing material. But, in disease, the kidneys may 



