Page:Encyclopædia Britannica, Ninth Edition, v. 1.djvu/847

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HISTORY.] so just a claim to the title of anatomist as Claudius Galenus, the celebrated physician of Pergamus, who was born about the 130th year of the Christian era, and lived under the reigns of Hadrian, the Antonines, Commodus, and Severus. He was trained by his father Nicon (whose memory he embalms as an eminent mathematician, architect, and astronomer) in all the learning of the day, and initiated particularly into the mysteries of the Aristotelian philo sophy. In an order somewhat whimsical he afterwards studied philosophy successively in the schools of the Stoics, the Academics, the Peripatetics, and the Epicureans. When he was seventeen years of age, his father, he informs us, was admonished by a dream to devote his son to the study of medicine; but it was fully two years after that Galen entered on this pursuit, under the auspices of an instructor whose name he has thought proper to conceal. Shortly after he betook himself to the study of anatomy under fSatyrus, a pupil of Quintus, and of medicine under Stra- tonicus, a Hippocratic physician, and ^schrion, an empiric. He had scarcely attained the age of twenty when he had occasion to deplore the loss of the first and most affectionate guide of his studies; and soon after he proceeded to Smyrna to obtain the anatomical instructions of Pelops, who, though mystified by some of the errors of Hippocrates, is commemorated by his pupil as a skilful anatomist. After this he appears to have visited various cities dis tinguished for philosophical or medical teachers; and, finally, to have gone to Alexandria with the view of cultivating more accurately and intimately the study of anatomy under Heraclianus. Here he remained till his twenty-eighth year, when he regarded himself as possessed of all the knowledge then attainable through the medium of teachers. He now returned to Pergamus to exercise the art which he had so anxiously studied, and received, in his twenty-ninth year, an unequivocal testimony of the confidence which his fellow-citizens reposed in his skill, by being intrusted with the treatment of the wounded gladia tors ; and in this capacity he is said to have treated wounds with, success which were fatal under former treatment. A seditious tumult appears to have caused him to form the resolution of quitting Pergamus and proceeding to Rome, at the age of thirty-two. Here, however, he remained only five years; and returning once more to Pergamus, after travelling for some time, finally settled in Rome as physician to the Emperor Commodus. The anatomical writings ascribed to Galen, which are numerous, are to be viewed not merely as the result of personal research and information, but as the common depository of the anatomical knowledge of the day, and as combining all that he had learnt from the several teachers under whom he successively studied with whatever personal investigation enabled him to acquire. It is on this account not always easy to distinguish what Galen had himself ascertained by personal research from that which was known by other anatomists. This, however, though of moment to the history of Galen as an anatomist, is of little consequence to the science itself; and from the anatomical remains of this author a pretty just idea may be formed both of the progress and of the actual state of the science at that time. The osteology of Galen is undoubtedly the most perfect of the departments of the anatomy of the ancients. He names and distinguishes the bones and sutures of the cranium nearly in the same manner as at present. Thus, he notices the quadrilateral shape of the parietal bones ; he distinguishes the squamous, the styloid, the mastoid, nnd the petrous portions of the temporal bones ; and he remarks the peculiar situation and shape of the sphenoid bone. Of the ethmoid, which he omits at first, he after wards speaks more at large in another treatise. The malar he notices under the name of zygomatic^bone ; and he 803 describes at length the upper maxillary and nasal bones, and the connection of the former with the sphenoid. He gives the first clear account of the number and situation of the vertebrae, which he divides into cervical, dorsal, and lumbar, and distinguishes from the sacrum and coccyx. Under the head Bones of the Thorax, he enumerates the sternum, the ribs (at TrAcupcu), and the dorsal vertebras, the connection of which with the former he designates as a variety of diarthrosis. The description of the bones of the extremities and their articulations concludes the treatise. Though in myol.ogy Galen appears to less advantage than in osteology, he nevertheless had carried this part of anatomical knowledge to greater perfection than any of his predecessors. He describes a frontal muscle, the six muscles of the eye, and a seventh proper to animals; a muscle to each ala nasi, four muscles of the lips, the thin cutaneous muscle of the neck, which he first termed platysma myoides, or muscular expansion, two muscles of the eyelids, and four pairs of muscles of the lower jaw the temporal to raise, the masseter to draw to one side, and two depressors, corresponding to the digastric and internal pterygoid muscles. After speaking of the muscles which move the head and the scapula, he adverts to those by which the windpipe is opened and shut, and the intrinsic or proper muscles of the larynx and hyoid bone. Then follow those of the tongue, pharynx, and neck, those of the upper extremities, the trunk, and the lower extremities successively ; and in the course of this description he swerves so little from the actual facts that most of the names by which he distinguishes the principal muscles have been retained by the best modern anatomists. It is chiefly in the minute account of these organs, and especially in reference to the minuter muscles, that he appears inferior to the moderns. The angiological knowledge of Galen, though vitiated by the erroneous physiology of the times and ignorance of the separate uses of the arteries and veins, exhibits, never theless, some accurate facts which show the diligence of the author in dissection. Though, in opposition to the opinions of Praxagoras and Erasistratus, he proved that the arteries in the living animal contain not air but blood, it does not appear to have occurred to him to determine in what direction the blood flows, or whether it was movable or stationary. Representing the left ventricle of the heart as the common origin of all the arteries, though he is misled by the pulmonary artery, he nevertheless traces the distribution of the branches of the aorta with some accuracy. The vena azygos also, and the jugular veins, have contri buted to add to the confusion of his description, and to render his angiology the most imperfect of his works. In neurology we find him to be the author of the dogma that the brain is the origin of the nerves of sensation, and the spinal chord of those of motion ; and he distinguishes the former from the latter by their greater softness or less consistence. Though he admits only seven cerebral pairs, he has the merit of distinguishing and tracing the distribu tion of the greater part of both classes of nerves with great accuracy. His description of the brain is derived from dissection of the lower animals, and his distinctions of tho several parts of the organ have been retained by modern anatomists. His mode of demonstrating this organ, which indeed is clearly described, consists of five different steps. In the first the bisecting membrane i.e. the falx (^VLJ^ St^oTo/AoC cra) and the connectingblood- vessels are removed ; and the dissector, commencing at the anterior extremity of the great fissure, separates the hemispheres gently as far as the torcular, and exposes a smooth surface (ryv x^P av ruXwSi; TTWS ovcrav), the mesolobe of the moderns, or the middle band. In the second he exposes by successive sections

the ventricles, the choroid plexus, and the middle partition.