24 FEEDING ANIMALS. 



The formula given by Johnston is as follows : 



COMPOSITION OF BONES. 



Gelatine 35 



Phosphate of lime 55 



(Containing phosphoric acid, 23.38) 



Carbonate of lime 4 



Phosphate of magnesia 3 



Soda, potash and common salt 3 



100 



This is from the mature animal. The bones of an 

 animal at birth do not contain more than 50 per cent, of 

 ash. 



Chemically considered, then, animal bodies consist of : 

 1st. Organic matters free from nitrogen. 2d. Organic mat- 

 ters rich in nitrogen fibrin and albumin. 3d. Inorganic 

 salts chloride of sodium, phosphate of lime, potash, etc. 

 4th. Water. These constituents of the animal body must 

 all be derived from the food. 



That most painstaking and accurate experimenter, to 

 whom all agriculturists are deeply indebted, Sir J. B. 

 Lawes, of Eothamsted, England, with his assistant, Dr. 

 Gilbert, undertook an experiment, *a few years ago, to 

 determine the proportion of the different parts of the 

 animal, and the composition of each part. The fat and 

 the nitrogenous or lean was carefully determined by analy- 

 sis in the dressed carcass, in the offal, and in the entire 

 animal. There were a large number of oxen, sheep and 

 pigs in these feeding experiments, and from these ten were 

 selected. These consisted of a fat calf, a half-fat ox, a fat 

 ox, a fat lamb, a store sheep, a half-fat old sheep, a fat 

 sheep, a very fat sheep, a store pig and a fat pig. 



The popular idea had been that all animals, except the 

 fattest, contained more lean flesh than fat. But this table 

 refutes this idea most conclusively. The fat ox and fat 

 lamb contained about three times as much fat as lean flesh. 

 This table, which we give, contains very precise evidence 



