6o 



consequence, among the hardiest animals of the whole equine tribe. They 

 have been specially trained to their mode and habits of life, and artificial 

 selection by man of the hardiest dams, and the dying off of the weaker 

 animals, have contributed to this result. Horses should, however, not 

 be expected to undergo prolonged fasts in our country. Moreover, it 

 is to be borne in mind that in Tartary the animals are not given large 

 quantities of oats, hay, and other fodder in abundance immediately after 



•exertion. They are carefully managed, and are hardy in consequence. 



When food is swallowed, the gastric glands pour out a juice — the "gastric 



juice" — and this, unlike the saliva, which acts on the starchy foods, acts on 



the albuminous constituents, and renders them capable of absorption through 

 the intestinal walls. It also dissolves the albuminous coatings of the fat 

 cells, and liberates the fat to be acted upon by the bile. The httle picture 

 shows the structure of these glands which secrete the juice in man, magnified 



.about 350 times. The large round cells are those which secrete the juice. 



When we consider the changes the food has to undergo in the mouth 

 ;and stomach before it can be absorbed, it will be seen that two hours should 

 be allowed before a horse is worked after being fed. There is one more fact 

 which we must mention, before passing on to the disorders of the stomach, 

 and it is one which clearly indicates that the structural peculiarities of the 

 horse show us that he is by nature a constant feeder. In man ; in the 

 ruminating animals, such as sheep, camels, deer, oxen, giraffes ; and in the 

 carnivora, such as the dog, cat, lion, tiger ; and many other animals, the 

 bile, which is a fluid secreted by the liver, is collected in a little bag or sac, 



