78 PHYSIOLOGY AT THE FARM. 



side the truth lies, there remains a great gap in the descrip- 

 tion of animal nutrition. 



As the food received into the stomach consists of proximate 

 organic principles, quite analogous to or rather identical with 

 the proximate organic principles that constitute the solids 

 of the living animal fabric, it seems, on a superficial consid- 

 eration, the mere pursuit of a close analogy to assume, that 

 as dead organic substance from without is undeniably a source 

 of nutrition, so disintegrated organic matter from within 

 should be a second source of nutrition. But here the death 

 which indeed inevitably follows on the mere plucking of a 

 flower is not distinguished from the complete chemical death 

 exemplified in its final rotting. 



"When I have plucked the rose ; 

 I cannot give it vital growth again, 

 It needs must wither." 



So the grass made into hay withers ; but the proximate 

 organic principles of which it consists still retain their com- 

 position, until such complete chemical death, resolving them 

 into the pure mineral substances, takes place, as when it rots 

 in the dunghill. 



It is not necessary for the present object to determine 

 whether it be impossible for the chemist to succeed hereafter 

 in producing from mineral nature compounds equivalent as 

 food in the animal world to albumen, fibrine, and the like ; 

 it is plain that organic compounds do not owe their fitness for 

 the food of animals to any remains of vitality in them, since 

 their nutritive virtue is, for the most part, not impaired, but 

 improved by processes so destructive of vitality as those of 

 cookery. The necessity, then, for organic products to consti- 

 tute the food of animals may lie merely in the near coincidence 

 between the chemical composition of such products and that 



