862 INFLUENCE OF OXYGEN GAS ON 



When it was discovered that animal life cannot 

 be supported without the inspiration of oxygen, 

 physiologists began to regard this gas as the pri- 

 mary cause of vital action. In accordance with 

 this view, it is observed by a writer in the Monthly 

 Chronicle, that " of the two animal wants, air and 

 warmth, the former is incomparably the more 

 important," and that " oxygen is the life sustain- 

 ing principle of the air." (vol i. p. 221.) But I 

 have already shown that the principal office of 

 oxygen is to supply animals with caloric, without 

 which it could no more maintain the action of the 

 heart, stomach, brain, and other organs, than it 

 could the movements of a steam engine. 



And that more caloric is imparted to the blood 

 during the respiration of oxygen, than of common 

 air, has been proved by the experiments of many 

 physiologists, who found that it increased the 

 temperature of the body, the action of the heart, 

 and with it the activity of all the functions ; while 

 it enabled the system to resist the influence of 

 external cold and that of the mephitic gases, for 

 a longer time than common air. From some ex- 

 periments of Count Morozzo, related by Dr. 

 Thomson, it would appear that sparrows are ca- 

 pable of living nearly five times longer when con- 

 fined in pure oxygen, than in the same quantity 

 of atmospheric air. For he found on placing them 

 one after another in a vessel of air, (with potass 

 for absorbing the carbonic acid,) that the first 



