112 DISTRIBUTION OF ARTERIES. 



property of the various foods, and other agents, which the 

 earth so liberally provides for their support and cure : these 

 form, in a great measure, the sound and sure foundation of 

 all medical science, whatever living individual animal is the 

 subject of our consideration/' 



DISTRIBUTION OF ARTERIES. 



The blood is propelled by the heart through the great 

 aorta, which rises out of the base of the left ventricle, in the 

 space between the left auricle and the pulmonary artery. 

 The branches furnished by the main trunk are the coronary 

 arteries. The right coronary artery emerges from between 

 the pulmonary and right auricle, winds round the fissure sepa- 

 rating that cavity from the right ventricle, and turns down 

 under the termination of the vena cava; and distributes 

 ramifications in its course, which penetrate the substance of 

 the parietes, and end in spiral branches. The left coronary 

 artery, in passing out between the pulmonary artery and left 

 auricle, sends off a large branch, which encircles the other 

 auricle ; it then takes its course downward, and ends in spiral 

 ramifications, 



ANTERIOR AORTA. 



This is a shorter division of the main trunk. The course 

 of this vessel is under the windpipe ; it gives origin to those 

 large arteries which are distributed over the breast, head, 

 neck, brain, and anterior extremities. It divides, at a short 

 distance from the heart, into the right and left arteria innomi- 

 nata ; the right is considerably longer than the left, and 

 measures nearly as much again in circumference ; it forms 

 the trunk from which the two carotid arteries spring ; the 

 left terminates in the following vessels : — 



1. The dorsal artery. 2. Posterior cervical. 3. Vertebral. 

 4. Internal pectoral. 5. External pectoral. 6. Inferior cer- 

 vical. 7. Axillary. Each of these arteries ramify and anas- 

 tomoze with others, and are distributed to muscular and adipose 



