Animal Heat. 35 



There are a number of animals,, as the hedge- 

 hog, (hybernating,) which during the summer 

 become enormously fat, and sleep throughout the 

 whole of the winter. In this case, as no food is 

 taken, the body maintains its animal heat entirely 

 by the consumption of fat which has been stored 

 up in the system. 



The bear also disposes of himself nearly in the 

 same manner. It is also a notable fact that our 

 cattle lay on, during the summer, a great quantity 

 of fat, which is derived from the plentiful herbage 

 of the period. In both these instances we also 

 perceive the provision which is ensured towards 

 obtaining the necessary amount of warmth during 

 cold weather, and when food is either withheld or 

 not very abundant. 



Animal heat is not maintained by saccharine 

 bodies or fat alone. In carnivorous animals, as 

 the lion, tiger and wolf, whose diet is confined to 

 flesh, also the wild hunters of some countries who 

 occupy their time chiefly in the saddle, sufficient 

 fat cannot be obtained, nor are saccharine com- 

 pounds forthcoming. Natural warmth then must 

 be procured from another source. 



Wild animals in their natural state, and the 

 hunters of uncivilised nations, are on an equality. 

 The habits of both necessitate much exertion 

 activity of muscle and consequently waste or 

 decay. 



Flesh, upon which they live, being purely a 

 nitrogenous compound, would furnish none of the 



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