DOMESTIC ANIMALS 213 



perhaps, has made a snow man, and knows that unless he 

 can add new snow regularly, the body of the snow man will 

 soon waste away. All animal bodies are daily using up the 

 materials of the body. If this waste is not made up, the 

 bodies of animals, like the body of the snow man, soon 

 waste away. Now, just as the boy in cold climates supplies 

 new snow to his snow man's body to keep it whole, so 

 nature uses protein to build up the wasted materials of 

 animal bodies. 



Let us next consider the carbohydrates. Sometimes the 

 words starchy foods are used to describe the carbohydrates. 

 You have long known forms of these in the white material 

 of corn and of potatoes. The carbohydrates are formed of 

 three elements, carbon, oxygen, and hydrogen. The 

 office of this whole group of food is to furnish to animal 

 bodies either heat or energy or to enable them to store fat. 



In the next place, let us look at the fat in plant food. 

 This consists of the oil stored up in the seeds and other 

 parts of the plant. The grains contain most of the oil. 

 Fat is used by the animal to make heat and energy or to 

 be stored away in the body. 



The next animal food in the plant that we are to think 

 about is the mineral matter. The ashes of a burnt plant fur- 

 nish a common example of this mineral matter. The animal 

 uses this material in the plant to make bone, teeth, and tissue. 



The last thing that the plant furnishes the animal is 

 water, just common water. Young plants contain com- 

 paratively large quantities of water. This is one reason 

 why young plants are soft, juicy, and palatable. But, since 

 animals get their water chiefly in another way, the water 

 in feeding stuffs is not important. 



