8& SCIENTIFIC AGRICULTURE, 



strictly true, as both kinds of food produce heat and 

 energy. It is true that an animal cannot live on 

 food that contains no nitrogen. A dog, or horse, 

 or other animal, will starve if fed on starch alone. 

 There must be a proper mixture of both nitrogenous 

 and non-nitrogenous food, to build up and sustain 

 the body. 



197. Young animals, in whose bodies a rapid for- 

 mation of muscle is going on, require a great deal of 

 nitrogenous food, and all animals require more non- 

 nitrogenous, or carbonaceous food, in cold weath- 

 er than when the weather is warm. In very cold 

 countries, and during the winter in temperate cli- 

 mates, men will eat more fat meat than in summer. 

 The Esquimaux, a people that live in the intensely 

 cold regions of the frigid zone, drink oil and melted 

 fat, which are consumed in their bodies like fuel in 

 a stove or fireplace, and supply heat for the body. 



198. Fat in animals, like starch, sugar, and oil 

 in plants, contains no nitrogen, and, when an animal 

 is not fed, this fat wastes away first in other words, 

 is consumed. If the animal be exposed to great cold 

 without extra food it cannot fatten. The reason, 

 therefore, that animals protected from the cold of 

 winter fatten much faster than when exposed, is, that 

 what would accumulate as fat is used in keeping the 

 animal warm. 



199. The earthy, or inorganic matter, in plants is 

 as necessary for animal growth as the organic mat- 

 ter. The bony skeleton consists chiefly of calcium 



