24 THE VETERINARY SCIENCE. 



the branch which runs backwards from the heart, we find it a 

 very long-, large artery, passing just below the spine, between 

 the kidneys, breaking up about six inches behind them into four 

 large branches — two on the left and two on the right side. 

 One on the left goes to supply the left hip and organs in the pelvic 

 or hip cavity, while the other passes down the left leg to supply 

 it with blood; one on the right side helps to supply the right hip 

 and pelvic cavity, while the other passes down the right leg. 

 This large branch, in passing back along the spine, gives oflF 

 small branches— one to the liver, one to the spleen, one to the 

 stomach, and branches to the large and small bowels, and one 

 to each kidney. 



Arteries are the vessels which carry the blood away from the 

 heart to the different parts of the body. They always carry the 

 pure blood of the body, which is a bright red color. When the 

 Kit ventrical contracts it causes a wave, as it were, to pass all 

 down through the arteries. This is an important point in con- 

 nection with the pulse of a horse. The walls of the arteries are 

 made up of elastic tissue, and after death are always lying open, 

 and, also, you never find and blood in them after death, the 

 reason is because they contract and force the blood all out before 

 they loose the power of contracting. 



How to Tell When an Artery is Cut.— The blood comes out 



in spurts every time the heart beats, and is of a bright red color. 

 Arteries are always found deep-seated and well protected with 

 muscles and bone; as, for instance, the large arteries of the legs 

 always pass down on the inside of the leg very close to the 

 bone, and on account of this vi^e very rarely have large arteries 

 injured. Towards the end of the arteries they are found to break 

 up into very small ones which run into the capillary network 

 of the body. These are numerous very small vessels about ^^ 

 of an inch in diameter. Their walls are very thin and cannot be 

 distinguished except under a microscope, and are found in all 

 parts of the body. As the blood passes slowly through these small 

 vessels, the nourishment is absorbed from the blood through the 

 very thin walls to supply the tissues of the body. When the 

 blood passes through this capillary network it again enters into 

 larger vessels called the veins, which carry it on its road back to 

 the heart. In starting at the head to trace the blood back to the 

 heart, we find it carried from the head by two very important 

 vessels called the jugular veins ; these are important on account 



