GALE'NUS, CLATPDIUS, one of the moot celebrated and valuable of the ancient medical writers, was born at Perg,IIIDUDI, A.D. 131. The exact time of his death is not known, but as he epeake of Perth= and Severna as emperors, we may conclude that Strides (v. casopeis) is not far from the truth in stating that he lived to the laze of seventy. He was early instructed in the doctrines of the Aristotelian sad Pla tonic philosophy, and appears also to have devoted some time to the study of the peculiar tenets of the other sects; for while yet very young, he wrote commentaries on the Dialectics of the Stoic Chrysippus.
His anatomical and medical studies were commenced under Satyrue, a celebrated anatomist; Stratonicus, a disciple of the Hippocratic school; and iEechrion, a follower of the Empirics. After the death of his father he travelled to Alexandria, at that time the most famous school of medicine in the world. His studies were ea zealously and sueceeefully pursued, that he was publicly invited to return to his native country. At the age of thirty-four he settled himself in 'tome, when his celebrity became so groat from the success of his practice, and more especially from his great knowledge of anatomy, that Ito quickly drew upon himself the jealousy of all the Roman physicians. At the solicitation of many philosophers and men of rank, ho com menced a course of lectures on anatomy ; but by the jealousy of hie rivals be was quickly compelled to discontinue them, and eventually to leave Rome eutirolr.
The instruction which Galen brad received in the principles of the various mete of medical philosophy, had given him an acquaintance with the peculiar errors of each, and ho speaks of them all at times in the language of no meaeured contempt. The school which was founded by himself may justly merit the title of Eclectic, for its doctrines were a mixture of the philosophy of Plato, of the physics and logic of Aristotle, and of the practical knowledge of Hippocrates. On many occasions ho expresses himself strongly on the superiority of theory to mere empiricism ; but upon those matters which do not admit of being objects of experience, such as the nature of the soul, ho confesses his iguorance end inability to give any plausible explanation.
But in order to form a correct estimate of the merits of this physi cian, it is necessary for us to mention particularly some of his contri butions to medical science. Anatomy was at all times the favourite
pursuit of Galen, but it does not appear that he had many oppor tunities of dissecting the human subject. This we may infer with certainty from the gratification he expresses at having discovered a human skeleton at Alexandria, and having been enabled to make observations on the body of a criminal which had remained without buriaL His dissections were principally confined to the apes and lower animals; and it is to this circumstance that many of the errors in his description are rcferrible ; for from the examination of these animals be attempted to infer analogically the structure of the human body. He describes the sternum as consisting of seven pieces instead of eight. He supposes the eacrum to consist of three pieces instead of five, and looks upon the coccyx as a fourth, whereas it is a distinct bone in men till twenty or twenty-five, and in women as late as forty-five.
His descriptions of the muscles appear to be more generally correct. He described for the first time two of the muscles of the jaws, and two which move the shoulder. In addition to these he discovered the popliteal muscles and the platysma myoides. He denied the muscular texture of the heart on account of the complicated nature of its functions, but he gave a good description of its transverse fibres and its general structure. The knowledge of the vascular system which Galen possessed does not appear to have been greater or more accurate than that of his predecessors. Ho supposed the veins to originate in the liver, and the arteries to take their rise from the heart. He like wise showed by experiment, in opposition to Erasistratus, that the arteries contained blood. and not merely the animal spirits, as that physician maintained. He had observed the structure and use of the valves of the heart, and, arguing from their evident intention, con cluded that a portion of the blood passed with the animal spirits from the pulmonary artery into the pulmonary vein, and so to the left side of the heart. He was also aware of the connection between the veins and arteries by means of the capillary vessels. The existence of the ductus arteriosus and foramen ovals during the stage of foetal life was not unknown to him, and he had also noticed the changes which they undergo after birth.