ggl^ Medicine. [Chap. IV, 



pired. This theory was adopted and illustrated 

 by M. Hasserifratz, who succeeded in proving 

 its superiority to that of Lavoisier and his associ- 

 ates. Tlie establishment of this theory depended 

 upon proving that the oxygenous portion of the 

 atmosphere alone is absorbed from the inspired air. 

 This was indeed the generally received opinion of 

 chemical philosophers for some time ; but as it has 

 lately been brought into question, and the contrary 

 asserted, it is proper to notice the variation of 

 theory which has thence been attempted to be 

 made. 



Mr. Davy h^s endeavoured to prove that azote, 

 as well as oxygen, is partly absorbed by the lungs 

 in respiration. As the azote which disappears in 

 breathing is not to be found in the products of 

 respiration, it has been thence concluded that it 

 is absorbed by the blood. The experiments of 

 Mr. Davy led him to believe that atmospheric air 

 is absorbed by the blood in an undecomposed and 

 unaltered state ; that it is afterwards decomposed 

 in that fluid by the afhnity of the red particles for 

 its oxygen ; tliat the greater part of the aaote is 

 liberated without undergoing any change, and 

 again given out and mixed with the air in expira- 

 tion; but that a minute portion of it remains con- 

 densed in tlje serum and coagulable lymph, and 

 passes with them to the left ventricle of the heart. 

 A miimte examination and decision as to the cor- 

 rectness of these facts> will not be attempted in this 

 place. But admitting the facts to be justly stated, 

 the following changes will appear to be produced 

 by respiration. The blood in passing througli the 

 lungs absorbs a portion of air, and carries it along 



