32 THE farmer's VETERINARIAN 



forced into the right ventricle; this in turn con- 

 tracts and forces the blood into the lungs, where 

 oxygen is taken on and carbonic acid gas and other 

 impurities are thrown ofif. From the lungs the 

 blood, now red and pure, passes into the left auricle 

 and thence into the left ventricle, from which it is 

 forced into the aorta to be distributed to all parts 

 of the body. 



We now see the close connection existing be- 

 tween the digestive system and the circulatory 

 system. The digested food in the intestines is 

 gathered in by villi cells. The question can now 

 be asked. What do these cells do with this nutri- 

 ment or digested food? They pour it into the 

 absorbent vessels or lymphs, as they are called; 

 these in turn empty the assimilated stores of food 

 into larger and still larger vessels, which continues 

 until the whole of the nutritive fluid is collected 

 into one great duct or tube, which pours its con- 

 tents into the large veins at the base of the neck, 

 from whence it is carried into the circulatory sys- 

 tem, the very basis of which is the blood. 



RESPIRATION 



The dark and impure blood, after returning to 

 the heart, is sent to the lungs. It is, when collected 

 from the body, just before being sent to the lungs 

 dark, dull and loaded with worn-out matter. It 

 must now be sent to the lungs, where it may be 

 spread over the delicate thin walls of millions of 

 vesicles, to be exposed to the air, which is inhaled 

 by the acts of breathing. The blood gives off the 

 broken-down material and carbonic acid gag very 

 readily. It is both unpleasant and disagreeable, 

 and the blood cells find it very unattractive. 



