There is always much water in all parts of the body. Often 

 one-half of an animal is water. Water itself becomes a part of all 

 bone and flesh, but its chief use is to carry building material. 

 When an animal eats, the food goes into the stomach and is there 

 acted upon by different juices. The proper parts are then taken by 

 the blood, which is mostly water, to every part of the body which 

 needs repair. Water also helps to carry off the wastes, or worn 

 out parts of the body. 



The mineral inatter in the body of an animal is found mostly in 

 its bones. Flesh and muscle are so soft that they cannot stand hard 

 use alone, and so they are placed on a bony framework. From two 

 to live per cent of the animal body is mineral matter. 



Nitrogenous tnatter is a term the chemist uses for all parts of the 

 body which contain nitrogen. This is the same element you are 

 feeding to your farm crops ; for plants as well as animals must have 

 nitrogen. Flesh, skin, muscle, hair, wool, horn, hoof, feathers, 

 blood, lean meat, the white of an o,^^ and the curd of mild all con- 

 tain nitrogen. When you put horn and hoof waste or dried blood 

 on your land they give up their nitrogen to the plants, and thus 

 have a fertilizer value. 



Yi\Q,fat of an animal varies with its age, the amount of work it 

 has to do, and the food it gets. The leanest animal has seldom less 

 than five per cent of fat, and the fattest not much above thirty per 

 cent. Fat is a sort of store or reserve supply of food. Late in the 

 fall a fat bear goes to sleep in a hollow tree. When he come out in 

 the spring his ribs show through his hide. He has lived all winter 

 on the reserve fat stored in his body when autumn nuts and berries 

 were abundant. 



6. Fat keeps the hody war7n. — All the higher animals are warm 

 blooded and this body heat must come from the food. That is why 

 most animals eat more food in cold weather than in warm weather ; 

 and why you yourself relish fat more often in winter than in sum- 

 mer. The Esquimaux and other people of very cold climates, live 

 almost wholly on fatty meats. They need a lot of the little heat- 

 giving atoms to keep them warm. 



Fat-producing materials are given to the animal, sometimes in the 



540 



