Artery

[Fr. artère; Gr. arteria, from aer, air, and tereo, to preserve or contain: so called because the ancients believed that the arteries contained air only.] ( Anat. ) A membranous pulsating canal, that arises from the heart and gradually becomes le as it proceeds from it. A. are composed of three ti ues: the inner, continuous with the inner membrane of the heart, resembles the serous membranes; the middle ti ue is fibrous and elastic; the outer ti ue, cellular and also elastic. The fibres of the middle ti ue are disposed circularly. They are only two in number, the pulmonary A., and the aorta, and these originate from the heart; the pulmonary A. from the right ventricle, and the aorta, conveying the blood from the left to all parts of the body (Fig. 201). The other arteries are all branches of the aorta. Fig. 120 explains perfectly the course of this great A., from its commencement in the heart to its termination; also of all the great branches which arise from it. Their termination is either in the veins, or in capillary exhaling ve els, or they anastomose with one another. It is by their means that the blood is carried from the heart to every part of the body, for nutrition, preservation of life, generation of heat, and the secretion of the different fluids. The action, called the pulse, corresponds with that of the heart, and is effected by the contraction of their muscular, and great elasticity of their outermost coat. (See CIRCULATION, and HEART.) - The pulmonary A., after emerging from the right ventricle of the heart, soon divides into a right and left branch, IMG:content-0351.png:[blocks in formation] Arte's ia, in Mi i ippi, a post-office of Lowndes co., 219 m. N. by W. from Mobile.