( 304 ) 



EXTRACTS FROM THE JOURNALS. 



SOME CHEMICAL POINTS CONNECTED WITH THE 

 FEEDING OF CATTLE. 



BY WILLIAM PROCTOR, YORK, ENGLAND. 



One of the greatest physiological distinctions between the ve- 

 getable and animal kingdoms consists in the different food they 

 respectively require for their nutrition and growth — the latter 

 consuming organized materials for that purpose; whilst for the 

 former division, unorganized and mineral matters effect the same 

 end, and become converted into organic substances necessaiy ibr 

 the support of animals. In this manner, dependent upon the pro- 

 perty it possesses of converting inorganic material into organic 

 food, does the vegetable prove subservient to the animal king- 

 dom by affording it food for growth and sustenance, assimilated 

 by the organs of plants into albumen, gluten, and casein, from 

 carbonic acid, the refuse of animal respiration; from the nitrogen 

 of the air, and from the minerals. A little consideration will 

 show that the difference between the nutrient principles of plants 

 and animals is more real than apparent; in fact that they are 

 identical. Liebig divides the substances of which the food of 

 man is composed into two great classes: I. Those into which 

 nitrogen enteis as a constituent — azotized. 2. Those into the 

 constitution of which nitrogen does not enter — non-azotized. 

 The individual substances, according to the above arrangement, 

 stand thus: 



I. Vegetable Jllhmieii (as the kernel of nuts, &c.); vegetal le 

 fibrin (or gluten, as in wheat); vegetable casein (or legumin, in 



peas, beans, &c.) Exactly identical in composition are, animal 

 albumen (as white of egg); animal fijrin (principal part of ani- 

 mal muscle); animal casein (entering largely into the composi- 

 tion of milk.) 



II. Fat, starch, gum, various kinds of sugar, alcohol, &c. 



Chemical and physiological research have shown, unquestiona- 

 bly, that among the above substances, the pro\'imate prinriples of 

 animals and vegetables, those alone can afford support to an ani- 

 mal which contain nitrogen, or belong to the first division; and 



