108 THE BOOK OF ENSILAGE. 



tie glandular lobules which compose the liver. Here 

 they break up into a plexus of microscopic vessels as 

 fine as those which originally absorbed from the intestines 

 the nutritive matter with which they are filled. These 

 minute vessels fill the entire substance of the liver with 

 a vascular net-work. Then these little vessels collect 

 together again, and unite into larger ones, until at last 

 they leave the liver as the hepatic vein, which conveys 

 the nutritive matter called chyle. Chyle is also absorbed 

 by the lacteal vessels, and conveyed by the thoracic duct 

 to the sub-clavian vein, and by both sets of vessels is 

 conveyed into and finally mingled with the venous blood 

 returning to the heart. By the contraction of the right 

 auricle it is forced into the right ventricle, which in turn 

 contracts, and forces the blood into the pulmonary artery, 

 which conveys the blood, chyle, and alcohol ? to 

 the lungs. There this artery divides into numberless 

 branches which penetrate and encircle all the minute 

 spaces between and about the air-vesicles. Here the 

 blood is subjected to the action of the air which is in- 

 haled by the lungs. Now, alcohol is very volatile ; and if 

 any of the alcohol has got thus far with the blood on its 

 way to the milk, there can be no doubt that it would all 

 be thrown off with the expiration of the breath. 



But, having followed it thus far, let us go clear 

 through to the churn, whether the alcohol keeps up with 

 us or not 



From the lungs the blood is returned to the heart, 

 which by the contraction of the left ventricle forces it all 

 through the system. A large amount of blood is carried 

 to the milk-glands. The milk-glands' office is to secrete 

 milk. They secrete nothing else which is in the blood 

 excepting those elements which constitute milk, pro- 

 viding the animal is in a healthy condition. 



