218 ANIMAL MATTEE. 



654. Animals, like plants, consist almost entirely 

 , of four elements, but these are grouped or combined 

 together to form various different compounds. The 

 bodies of all living animals contain a considerable 

 quantity of water : when this is evaporated by heat, 

 there remain certain substances, which may be readily 

 separated from each other in consequence of the 

 different properties which they possess, just in the 

 same way that we can separate the various substances 

 which compose plants (318). 



555. The constituents of the bodies of animals may 

 be naturally divided into the organic substances of 

 which the softer parts of animals are composed, and 

 the earthy or inorganic matters, such as the bones. 



556. Animal substances, for the most part, are ra- 

 ther more complicated in their nature than vegetable 

 substances; they almost all consist of oxygen, hy- 

 drogen, carbon, and nitrogen ; in consequence of the 

 presence of this latter element, they are more liable 

 to decompose than those vegetable substances which 

 do not contain it. 



557. The principal substances which compose the 

 bodies of animals, and which are, therefore, called 

 proximate animal principles, are : albumen, fibrin, 

 caseine, gelatine, and fat, or oil ; besides these, 

 chemists have detected a multitude of other sub- 

 stances ; but these five are the most important, or 

 those which constitute the greater bulk of animal 

 matter. 



558. There are many varieties of albumen and 



