72 The Feeding of Animals 



be derived, therefore, wholly from air and water, and 

 they constitute that portion of our cattle foods which 

 is drawn from never -failing and costless sources of 

 supply. 



The elementary composition of typical nitrogen - 

 free bodies is given in this connection: 



Cellulose Starch Glucose Saccharose Stearin Olein 



* < * * * 



Carbon 44.4 44.4 40. 42.1 76.7 77.4 



Hydrogen . 6.2 6.2 6.7 6.4 12.4 11.8 



Oxygen 49.4 49.4 53.3 51.5 11. 10.8 



The non- nitrogenous compounds of feeding stuffs 

 are usually divided into three main classes, viz. ; crude 

 fiber, nitrogen -free extract and fats or oils. The sec- 

 ond class is sometimes spoken of as carbohydrates, 

 because it includes the carbohydrates as its principal 

 members, and the third is known by the chemist as 

 ether -extract, because ether is used to extract the fats 

 or oils from the vegetable substances in which they are 

 contained. The actual fat obtained from hay and 

 other feeding stuffs is always less, however, than the 

 ether -extract. 



CRUDE FIBER 



This is the tough or woody portion of plants. It 

 consists largely of cellulose, a familiar example of 

 which in a nearly pure form is the cotton fiber used 

 in making cloth. Crude fiber is separated from asso- 

 ciated compounds by the successive treatment of vege- 

 table substance with weak acids and alkalies, and as so 

 determined is sometimes improperly taken to represent 



