THE STOMACH. 207 



direction. It is so constructed at its entrance into the stomach, 

 that a return of the food hy vomiting is almost. impossihle. 



The stomach of the horse is so situated that it must be dis- 

 placed and driven back by every contraction of the diaphragm 

 (midriff) or act of inspiration ; and in proportion to the fulness 

 of the stomach will be the weight to be overcome, and the laboi 

 of the diaphragm, and the exhaustion of the animal. Hence 

 the frequency and labor of the breathing, and the quickness with 

 which such a horse is blown, or possibly destroyed. Hence also 

 the folly of giving too full a meal, or too much water, before the 

 horse starts on a journey or for the chase. 



The stomach has four coats. The outermost is the lining of 

 the cavity of the belly, and the common covering of all the 

 intestines — that by which they are confined in their respective 

 situations, and from which a fluid is secreted that prevents all 

 friction between them. This is called the peritoneum, — ^that 

 which stretches round the inside of the stomach. 



The second is the muscular coat, consisting of two layers of 

 fibres, one running lengthways, and the other circularly, and by 

 means of which a constant gentle motion is communicated to the 

 stomach, mingling the food more intimately together, and pre- 

 paring it for digestion, and by the pressure of which the food 

 when properly prepared is urged on into the intestines. 



The third, or cuticular {skin-like) coat, c, covers but a portion 

 of the inside of the stomach. It is a continuation of the lining 

 of the gullet. There are numerous glands on it, which secrete a 

 mucous fluid ; and it is probably intended to be a reservoir in 

 which a portion of the food is retained for a while, and softened 

 and better prepared for the action of the other or true digestive 

 portion of the stomach. The cuticular coat occupies nearly one 

 half of the inside of the stomach. 



The fourth coat is the mucous or villous (velvet) coat, e, where 

 the work of digestion properly commences. The mouths of nu- 

 merous little vessels open upon it, pouring out a peculiar fluid, 

 the gastric (stomach) juice, which mixes with the food already 

 softened, and converts it into a fluid called chyme. As this is 

 formed, it passes out of the other orifice of the stomach, the pylo- 

 ms (doorkeepers), yi and enters the first small intestine ; the harder 

 and undissolved parts being turned back to undergo farther action. 



The stomach is occasionally subject to inflammation and 

 various other injuries. 



The symptoms, however, are obscure and frequently mistaken. 

 They resemble those of colic more than anything else, and should 

 be met by bleeding, oily purges, mashes, warm gruel, and the 

 application of the stomach-pump : but when, in addition to the 

 colicky pains, there appear indistinctness of the pulse — and a 



