Page:Greek Biology and Medicine.djvu/111

 PROGRESS IN ANATOMY only by the persistent ancient error that the arteries carried, not blood, but air. He conceived illness as resulting from the loading of the parts of the organism with in- sufficiently digested food-matter; which pre- vented the organism from functioning. This made a condition of " plethora," from which resulted the various sicknesses. Thus he re- garded fever (which he did not consider in itself a special disease, but a symptom) as re- sulting from a stoppage of the circulation of the pnewna in the large arteries, due to the intrusion of blood from overloaded veins. He sought to remove the " plethora " as the cause of the disease; but did not concern himself in practice with the remoter causes of the plethora itself. Thus his diagnosis was local and special, — " Cnidian " indeed, — and did not follow the larger and far-reaching lines of the Hippocratic prognosis. It may be supposed that the therapeutic principles of Erasistratus did not lead practi- tioners to apply the growing knowledge of anatomy to the cure of disease. The applica- tion was too baffling. Yet the rivalry between his school and that of Herophilus brought the practice of medicine to its zenith in the years [89]