THE STO:S[ACH. 



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a valve, but it is a strong and almost insuperable obstacle to the regur- 

 gitation of the food. 



THE STOMACH. 



a The oesophagus or gullet, extending to the stomach. 



h The entrance of the gullet into the stomach. The circular layers of the muscles are 

 very thick and strong, and, by their contractions, help to render it difficult for the 

 food to be returned or vomited. 



r The portion of the stomach which is covered by cuticle, or insensible skin. 

 d d The margin, which separates the cuticular from the ^•illous portion. 

 e e The mucous, or villous (velvet) portion of the stomach, in which the food is princi- 

 pally digested. 



f The communication between the stomach and the first intestine. 



q The common orifice through which the bile and the secretion from the pancreas pass 

 into the first intestine. The two pins mark the two tubes here united. 



The stomach is situated on the left side of the abdomen, in what is 

 termed the hypochondriac region, a small portion extending to the epi- 

 gastric region. Its anterior part is in connection with the liver ; its left 

 extremity with the diaphragm and spleen. 



The situation of the stomach will at once explain the reason why a 

 horse is so much distressed, and sometimes irreparably injured, if worked 

 hard immediately after a full meal. The stomach must be displaced and 

 driven back by every contraction of the diaphragm, or act of inspiration ; 

 and in proportion to the fulness of the stomach will be the weight to be 

 overcome, and the labour of the diaphragm, and the exhaustion of the 

 animal. If the stomach is much distended, it may be too weighty to 

 be forced suflG.ciently far back to make room for the quantity of air which 

 the animal in a state of exertion requires. Hence the frequency and labour 

 of the breathing, and the quickness with which such a horse is blown, or 

 possibly destroyed. Hence also the folly of gi'V'ing too full a meal, or too 

 much water, before the horse starts on a journey or for the chase ; and, in 

 like manner, the absurdity and danger of that unpardonable custom of 

 some grooms to gallop the horse after his drink, in order to warm it in 

 his belly, and prevent gripes. 



The horse was destined to be the servant of man, and to be always at his 

 call whether fasting or full : it would seem, therefore, that, to lessen much 



