i6 



FEEDING FARM ANIMALS 



number of the carbon and hydrogen units in pro- 

 portion to the oxygen than in the case of starch. 

 While all plants contain some oil or fat in their 

 woody tissue, the great bulk of it is deposited in the 

 seed or the fruit. 



Protein differs in composition from oil or starch 



in having nitro- 

 gen and sulphur 

 in addition to car- 

 bon, hydrogen and 

 oxygen. 



What Plant 

 Building Means. 

 Before the simple 

 elements are 

 taken into the 

 plant they are of 

 little value. No 

 animal can use 

 them as food; 

 they cannot be 

 burned to furnish 

 heat ; and they 

 store up no en- 

 ergy to carry on 

 any of the world's 

 work. What a 

 change the plant 



makes of them ! Without value in soil and air, these 

 elements when taken into the plant and built into 

 tissue at once become of vast importance. They be- 

 come the source of all animal food, and, constructed 



LEAF CELLS 



How the cells from the interior of a leaf 

 look when seen under the microscope. 



