136 THE PRINCIPLES OF AGRICULTURE. 



well filled, partly with solid food, and partly with liquids, 

 a small quantity of the food near the lower entrance to 

 the gullet is floated upward by the liquid into the mouth 

 by a slight contraction of the stomach. The animal 

 grasps the solid part in its mouth, swallows the liquid, 

 and proceeds to masticate the food, reducing it to a finer 

 and softer condition. As this is again swallowed, such 

 parts as are sufficiently fine and soft pass into the third 

 and fourth stomachs, and the remainder passes into the 

 paunch to be returned to the mouth a second time. 



In order that rumination may go on, it is necessary 

 that the paunch be quite well filled, and that there shall 

 be enough liquid to separate and float the solid food 

 freely. 



Ruminants, when supplied with sufficient water, are 

 able to live without food for a long time, as they are 

 able to make use of the large store of food in the 

 paunch, which is -gradually reduced to a fine condition, 

 and passed along to the fourth stomach and intestine (c?) 

 for digestion. 



The Blood. The blood, in its circulation, is the car- 

 rying system of the animal body. The tubes through 

 which it passes become so small by subdividing that the 

 blood is practically brought in contact with, and moistens, 

 all parts of the system. 



As the substances formed from the food pass from the 

 stomach and intestines into the blood, they are imme- 

 diately carried forward with the current and distributed 

 through the system. 



The blood is forced along by the pumping action of 

 the heart. On leaving the heart, it passes into large 

 tubes called arteries (a, a, a). These soon begin to sub- 

 divide into smaller arteries, and these again into still 



