240 INDUCTION OF 



the living cells, or other organisms, with which the 

 decomposing food is brought in contact. 



The oxidation of the blood presents the same idea 

 to us perhaps in its simplest form. Certain particles 

 of the venous blood enter into union with the oxygen 

 of the atmosphere, with formation of carbonic acid : 

 a manifest process of decomposition. But another 

 part of the same blood, which resists this decompos- 

 ing action, or refuses to undergo it, receives there- 

 from an impulse which causes its higher vitalization 

 and fits it to be the agent in nutrition. Is there in 

 this process, regarded in its general outline, and 

 apart from theory, anything more hard of compre- 

 hension than the coincident fall and rise of the 

 respective arms of a balance? 



In the same light, also, may be viewed the higher 

 vitalization of the blood effected by its partial decom- 

 position in the secreting glands. And with these 

 may be classed the excretive or other decomposing 

 changes which so generally accompany the process 

 of metamorphosis. The silkworm spins its cocoon by 

 a decomposition or retrograde chemical action, which 

 imparts to the remaining blood a higher vital status 



