The first deserving of mention was Herophilus, who was born in Chalcedon about the end of the fourth century before Christ, and supposed to be the first to undertake systematic dissection of the human body. The so-called Torcular Herophili, or common meeting-place of the sinuses at the occiput, named after him, gives evidence of his influence upon the study of anatomy. He wrote on all departments of medical science, concerning the eyes, the pulse, midwifery, etc., as well as numerous commentaries upon the Hippocratic writings,--describing the membranes of the brain and its vessels, the choroid plexus, the ventricles of the brain, the tunics of the eye, the intestinal canal, and certain portions of the vascular system. He alluded to the thoracic duct without knowing its purpose, and gave a more accurate description of the genitalia than any previous writer. Strange to say, but little is known of his later life, and of his death absolutely nothing. Erasistratus{034} was the son of Cleombrotus, a student of Metrodorus, and lived for some time at the court of Seleucus Nicator, whose son, Antiochus, he healed of a secret ailment, which happened to be a desperate love-affair with his mother-in-law, Stratonice. He wrote extensively on fevers, hygiene, paralyses, therapeutics, and many other subjects; regarded most diseases as due to overindulgence in food, which is not digested, and consequently putrefies. Plethora was for him the prevailing disease, against which he employed not only venesection, but fasting, and bandaging of the extremities. He was a diligent student of anatomy, and carefully described the brain in many of its grosser features, regarding it as the seat of the soul and the centre of the nerves. He also described more exactly than his predecessors the valves of the heart, which organ he regarded as the origin of veins and arteries. He discovered the lymph-vessels, and maintained, against Plato and others, that the epiglottis prevents the entrance of fluids into the lungs, but he supposed digestion to be produced by mechanical trituration in the stomach, and preferred gymnastics, exercise, diet, and baths to drugs or other therapeutic measures. He died about 280 B.C.