Aorta

the main arterial trunk of the body. It from the left ventricle of the heart, and forming an arch acro the chest, descends in front of the vertebral column until it reaches the level of the fourth lumbar vertebra, where it divides into the two common iliac arteries. It gives off branches in its course, which supply the head, neck, arms, and trunk, while the iliacs, its terminal divisions, supply the elvis and lower imbs., [ BLoop- VESSELS.] At the junction of the aorta AORTA. and left ventricle are Arh of aorta; b, thoracic aorta; the aortic or semi- ¢, coronary arteries. lunar valves, which only ventricle opposite aortic which The aneurism province valley and where Bernard and occupation, here, this cheese, afficted mineral formerly North Atlas range. shoulder, fringe the the most most they The the desert, Arizona, to But has (1910) been brought into known etc. Inde, the to languages unpronounceable Apaches are Washita the in C. 1869), Indians, the the silk deception, ) Apatite. allow of the pa age of blood from the into the aorta, and prevent a flow in the direction from occurring. Just above the valves are the coronary arteries, by means of the heart itself is supplied with arterial blood. aorta is subject to various diseases, notably to (q.v.) and atheroma (q.v.). Aosta (cla ic August a Pretor i a),a town in the of Turin, Italy, situated in a lovely Alpine on the left bank of the river Dora Baltea, nearly 2,000 feet above sea level, at the point the descents from the Great and Little St. unite. The remains of an amphitheatre a triumphal arch, with other traces of Roman still exist. St. Bernard was archdeacon and Anselm of Canterbury was a native of place. The valley is fertile and produces rice, and hemp, but the inhabitants are terribly with goitre and cretinism. There are springs in the neighbourhood. The district, a duchy, bears the same name as the town. Aoudad (Ovis tragelaph us), a wild sheep of Africa, inhabiting the lofty woods of the It stands about three fcet high at the is reddish brown in colour, with a heavy of hair reaching from the neck to just about hoofs; horns about two feet long. Called also Barbary Sheep.