MANUAL OF AGKICULTURE. 253 



hair, wool, &c., and cliondrin in cartilage or gristle. The olea- 

 ginous compounds, or fat formers, supply material for storing up 

 fat in the system. The adipose or fat cells are congregated in 

 nearly every part of the system. In the case of animals fattened 

 beyond natural requirements these cells are deposited in increased 

 quantity in all the soft tissues, thus increasing the size and 

 plumpness of the different parts of the frame ; but at the same 

 time their presence greatly interferes with the continuance of mus- 

 cular vigour. They are also termed heat producers, as by the 

 oxidation of their carbon and hydrogen in the lungs and tissues 

 they serve to maintain the requisite temperature of the blood. 

 The amylaceous and saccharine bodies are termed the respiratory 

 or heat-producing compounds. Their carbon and hydrogen are 

 oxidised in the lungs and other parts, and carbonic acid and 

 water produced thereby, as in the case of the last-mentioned 

 compounds. It is supposed that their excess in the blood is 

 capable of conversion through exchange of atoms into fatty 

 material. As before mentioned, the production of heat ensues 

 upon all movements whatever of animal bodies. The oleaginous 

 and amylaceous compounds alike are incapable of supplying 

 flesh-formiug materials, the reason being that they do not con- 

 tain nitrogen. 



There is a peculiar modification of stomach represented amoDgst 

 the ruminant animals of the farm, those, namely, which are com- 

 monly said to " chew the cud." The stomach in their case is 

 divided into four different compartments, viz., 1st (in order 

 form the gullet), the rumen, or " paunch ;" 2d, the reticulum, or 

 honeycombed bag; 3d the omasum, or " manyplies; " and 4th, the 

 abomasum, or stomach proper. The gullet or oesophagus is con- 

 tinued to the third stomach ; but in passing over the openings 

 into the rumen and reticulum, it is slit in such a manner that a 

 small amount of pressure opens its folds, and affords a passage 

 into those two divisions. In the act of feeding, ruminant animals, 

 it will be seen, swallow their natural food before it is thoroughly 

 masticated. This, in being swallowed, deposits its bulkier and 

 more imperfectly chewed portions into the rumen and reticulum, 

 through the pressure of such portions upon the two folded open- 

 ings into the same respectively, the larger pieces naturally 

 entering the rumen. And there it remains, and is acted upon by 

 the saliva swallowed along with it, until the animal ceases 

 browsing. Meanwhile the reticulum has been receiving the 

 sup])ly of the rumen. When the animal, in the next place, com- 

 mences to ruminate, the contents of the reticulum are ejected 

 through the folds of its communicating aperture into the gullet 

 in the form of small pellets, and by an inverted muscular action 

 of the gullet these are conveyed to the mouth, where they 

 undergo a thorough leisurely mastication. Eeduced by this 



