46 HORSE MANAGEMENT IN INDIA 



nerves, glands, etc. — is composed of substances that come 

 under the nitrogenous group; "even the non-cellular liquids 

 passing out into the alimentary canal at various points — 

 which have so great an action in preparing the food in 

 different ways — are not only nitrogenous, but the constancy 

 of this implies the necessity of the nitrogen, in order that 

 these actions shall be performed." {Parhes) White of 

 Qgg is a familiar example of this group. These nitrogenous 

 substances consist of carbon — of which charcoal is a well- 

 known form — hydrogen and oxygen — the two constituents 

 of water — combined in various proportions with nitrogen, 

 and, in the case of albuminous substances, with a small 

 amount of sulphur. 



Both the fats and saccharine matters are composed of 

 certain combinations of carbon, hydrogen and oxygen. 

 In the latter, the two last-mentioned elements are united 

 in the proportion that forms water, so that sugar and 

 starch may be regarded as a combination of carbon with 

 that fluid ; but in the former, there is a small amount of 

 oxygen. The fat, which is deposited as a layer immediately 

 under the skin, serves to maintain the internal temperature 

 of the body, by the fact of its being a bad conductor of 

 heat. Fat also acts as a natural elastic cushion to various 

 parts of the system, as, for instance, at the back of the 

 eyeball, above the horny frog, and around the joints. 



Dr. Carpenter remarks, that "the muscular, nervous, 

 and glandular tissues are not composed of albuminous 

 substances alone ; they contain, as an essential constituent 

 of their structure, a certain portion of fat, without which 

 theu' composition would be imperfect, and the performance 

 of their functions impossible." Such fat, he points out, 



