COMPOSITION OF ANIMALS 



37 



Incombustible Matter. The bones contain the 

 largest part of the incombustible constituents. Here 

 are found calcium phosphate, calcium carbonate 

 and magnesium phosphate in greatest abundance. 

 Potassium phosphate heads the list in the tissues. 

 These mineral substances constitute from three to 

 five per cent of the live weight of the animal. 



Water. More than half of the entire weight of 

 the animal is water. It is to be found in all parts 

 of the body and is as essential for the development 

 of solid tissue as any of the other ingredients. 

 Young and growing animals, like young and grow- 

 ing plants, contain the highest percentage of water. 

 As the animal matures the proportion of water dimin- 

 ishes until it reaches about one-half of the total weight. 



Range of Variation of Materials. The amounts 

 of water, nitrogenous matter, fat, and the mineral 

 constituents present in a large number of animals 

 have been determined at Rothamsted Station in Eng- 

 land. The table following shows the range of variation 

 of the various constituents and for different animals. 



PERCENTAGE COMPOSITION OF WHOLE ANIMAL 



(WARRINGTON) 



The smallest amounts of both ash and protein 

 are found in the pig, the largest in the ox. Fat is 



