CONTENTS. The Human Skeleton. The Skull. The Vertebræ. The Bones ;- including the Ribs; Shoulder-blade; Collar-bones; Pelvis or PAGE The Brain and Spinal Marrow. The Heart, with its Arteries and Veins. The Lungs, Windpipe, and Epiglottis. The Stomach and Gastric Juice. Digestion. The Liver, and other Viscera.... 17 HUMAN ANATOMY SIMPLIFIED. FIRST LECTURE. HUMAN ANATOMY is the subject of the present course of Lectures. These Lectures will be strictly elementary. I do not propose nor profess to treat the subject scientifically; but in a plain, simple, popular style; avoiding, as far as possible, all learned, technical terms and phrases. I have been induced to take up the topics of Human Anatomy and Mental Philosophy, as forming two series of Lectures, from the consideration of the infinite importance of the science of Self-Knowledge; reminded of the ancient heathen saying, which the Greeks affirm was sent down from the gods,"Man, know thyself;"—of the maxim of one of our philosophic poets, "The proper study of mankind is MAN;" and of the exclamation of the devout Psalmist ;I will praise thee, O God; for I am fearfully and wonderfully made: marvellous are thy works; and that my soul knoweth right well. My substance was not hid from thee, when I was made in secret, and curiously wrought in the lowest parts of the earth. Thine eyes did see my substance, yet being imperfect; and in thy book all my members were written, which in continuance were fashioned, when as yet there was none of them.”—Psalm cxxxix. 14-16. The word ANATOMY is derived from two Greek particles, ava, through; and roun, a cutting. The word thus literally signifies to cut through, or to cut asunder; dissection, or a separation of the parts. As an ART, therefore, anatomy means simply the operation of dissecting, or artificially separating the parts of an animal body; but as a SCIENCE, it comprehends all the objects of such dissection; which, in general, are, to discover the various situations, figures, and connections, powers and B uses of the parts, with the structure, fabric, and economy of the whole. This science is usually divided into ANATOMY, properly so called, or HUMAN ANATOMY and COMPARATIVE ANATOMY. The former of these is usually applied to the examination of the structure and parts of the human body; the latter to that of the brute creation only. The science is believed to be very ancient, although many ages passed before it was brought to any degree of perfection. It would appear that Solomon, king of Israel, who was a profound natural philosopher, knew something of Anatomy, from some remarkable passages in the book of Ecclesiastes. Hippocrates, the most eminent of the Greek physicians, and styled the father of medical science, is the first author who treated of anatomy scientifically. Galen is, by general consent, acknowledged the prince of anatomists. The importance of this study cannot be over-rated in the education of the MEDICAL PROFESSION; it lies at the basis of all correct knowledge of the functions of the human body. Diseases cannot be properly understood without it; and it has been through its agency that many of the successful operations of surgery have been introduced. But anatomy is of use also in painting and statuary. Some of the great masters of these arts have paid particular attention to this study in order to give correct representations of the limbs and muscles of the human frame. A general knowledge, however, of the structure and functions of the human body, is useful to ALL PERSONS, as it may often be the means of preserving their health, and preventing many of the accidents which occur to life through ignorance. This science furnishes us with the most striking and convincing proofs of the wisdom, power, and goodness of the Creator; for the instances of benevolent contrivance, which every moment meet our view, are such as can hardly fail to strike the most careless or most prejudiced observer. I. The first subject on which we shall now treat will be THE HUMAN SKELETON. A skeleton is the bones of an animal body separated from the flesh, and retained in their natural position and connections. The human skeleton is divided into three principal parts,—the Head,―the Trunk,-and the Extremities or Limbs. II. In the examination of the skeleton we naturally direct our attention, in the first place, to * THE SKULL. This is the bone that forms the exterior of the head, and encloses and defends the brain. It properly consists of three principal parts, the frontal, including the forehead and bones. of the nose, eyes, and upper and lower jaws; and two sidebones. The upper bones of the skull are closely united by a rough edge, like that of a saw, the notches of which shut in to each other, as the teeth of a saw would do, and form what may be called seams." These seams are by anatomists called SUTURES. In early infancy, the parts of the skull, especially at the top of the head, are very imperfectly closed; so that you might feel, by the slightest pressure of your finger, the pulsations of the brain very distinctly. In process of time, however, the bones become more closely united, and at length are as firmly compacted as if there had never been any separation of the parts. As a person advances in life, these seams begin to be obliterated; till, in very old age, not a vestige of them is to be seen. The thickest bone in the skull is situated in the back of the head; which defends that part of the brain, the least injury to which proves fatal. It may further be observed, that when we fall forward, the hands contribute to protect us; and if we fall on one side, the shoulder in some measure protects the head; but if backwards, there is nothing to interpose, and the back of the head comes with great force to the ground; it was therefore necessary that the bone placed there should have some strength. Admire here the wisdom and goodness of the Creator in forming so strong a bone as the skull to defend the brain, which, if injured, occasions idiocy, madness, or death. III. From the back and lower part of the skull descends a series of bones called THE VERTEBRÆ. This is sometimes termed the spine, or back-bone. In the figure in the Frontispiece the upper part of the spine is marked á, and the lower a. The name VERTEBRÆ is derived from the Latin word VERTERE, to turn, as the body turns upon them as * See Skull in Frontispiece. |