WATERING AND FEEDING. 29 



these three series of muscles the food is rotated over the cuticular and 

 villous linings of the stomach ; whilst by the secretions of the softer or 

 villous lining it is supplied with a fluid called the gastric juice, which is 

 essential to the further process of digestion. The food at this stage is 

 called chyme. 



The action of the muscular coat producing rotation of the food is due 

 to nervous influence ; but the immediate stimulus on the nervous system 

 of the stomach is the food itself. When the stomach is quite empty, the 

 rotatory motion ceases, and the pouch is then in a state of contraction 

 and quiescence. 



During the successive rotations such portions of the food, as have 

 become sufficiently soluble, are gradually pressed forward and passed on 

 to the small intestines. In them it is further mixed with the secretions 

 of the pancreas, liver, and intestinal glands. The admixture of these 

 juices completes the preparation of the food, and it is now ready for 

 absorption into the system. 



The process of absorption is effected in the following manner. The 

 abdominal veins and the lacteal absorbent vessels of the intestinal linings 

 take up from the food its nutritive parts, which in this state are called 

 chyle. The chyle is carried by the absorbent vessels through the 

 mesenteric glands into the thoracic duct, and by it is ultimately 

 discharged into one of the large blood-vessels on the left side of the neck 

 near the heart. 



It is by this constant admixture of material taken up from the food 

 by the absorbents that the necessary supply of blood is maintained. 

 From the blood thus maintained by the food are furnished the materials 

 required for the maintenance and renewal of the body. The food 

 supplies the blood, which in its turn supplies the body. 



To revert to the course of the food. When the veins and absorbents 

 of the small intestines have taken up from the food its nutritive parts, 

 the refuse is passed on to the large intestines. In them a further system 

 of absorbents take up from the refuse whatever little nutriment may yet 

 remain in it ; and the residuum, along with the waste products of the 

 body excreted into the intestines, is cast forth by the anus as dung. 

 Such is the preparation and course of the food. 



54. Course of water. 



The course of water through the body is somewhat different from that of 

 solid food. Water does not lodge in the stomach, but merely passes 

 rapidly through it and the small intestines on its way to the caecum or 

 blind gut, which may be considered as the real water stomach of the 

 horse. The caecum, we may mention, is one of the large or lower intes- 

 tines. From the caecum the water is gradually taken up by the veins 

 and absorbents according to the requirements of the system, and poured 

 into the large blood-vessels in the neighbourhood of the heart. 



Eventually, along with the effete or worn out nitrogenous matters and 



