CONSUMPTION". 137 



while those that carry the blood for oxidation come 

 from the right heart. The blood which is sent to nour- 

 ish the lungs is bright red; that sent for oxidation is 

 dark venous, and contains many impurities. 



Uric Acid. 



Uric acid is the product of metabolism or tissue 

 change. Its chief source of supply is the liver. In 

 health this uric acid is oxidized; i. e., unites with the 

 oxygen from the air we breathe, is converted into urea, 

 and the urea is eliminated by the kidneys. As stated, 

 the return circulation carries many poisons from the 

 digestive tract to the liver, heart and the lungs. Uric 

 acid is also sent from the liver direct to the lungs. 

 Every poison in the system is carried by the return cir- 

 culation to the heart and sent direct into the lungs, 

 and inflammation is a frequent result. 



The amount of oxygen inhaled grows gradually less, 

 and the oxidation in the blood of certain unfinished 

 products is rendered less complete. The uric acid is 

 not converted into urea, but remains an irritating sub- 

 stance. 



Lactic Acid. 



Lactic acid exists in most parts of the body and is 

 supposed to be derived from muscle tissue. The excess 

 of this or uric acid is thought to be the cause of rheu- 

 matism. In health lactic acid is also oxidized and 

 converted into carbonic acid gas and water, and elimi- 

 nated by the kidneys and lungs. But with the dimin- 

 ished amount of oxygen taken into the system, this 



