Legend tells that Æsculapius was the son of Apollo by Coronis, who was killed by Artemis for unfaithfulness, and her body was about to be burnt on the pyre, when Apollo snatched the boy out of the flames and handed him over to the centaur Cheiron, who taught him how to cure all diseases. Pindar tells the story of his instruction in the art of medicine:— “The rescued child he gave to share Magnesian Centaur’s fostering care; And learn of him the soothing art That wards from man diseases’ dart. Of those whom nature made to feel Corroding ulcers gnaw their frame; Or stones far hurled, or glittering steel, All to the great physician came. By summer’s heat or winter’s cold Oppressed, of him they sought relief. Each deadly pang his skill controlled, And found a balm for every grief. On some the force of charmed strains he tried, To some the medicated draught applied; Some limbs he placed the amulets around, Some from the trunk he cut, and made the patient sound.”[331] It was believed that he was even able to restore the dead to life. According to one tradition, Æsculapius was once shut up in the house of Glaucus, whom he was to cure, and while he was absorbed in thought there came a serpent, which twined round his staff, and which he killed. Then he saw another serpent, which came carrying in its mouth a herb, with which it recalled to life the one that had been killed; and the physician henceforth made use of the same herb to restore dead men to life, the popular belief, even in these early times, evidently being that what would cure serpents would be equally efficacious for men. We may therefore consider the snake-entwined staff of the healing god as the symbol of the early faith in the efficacy of experiments on animals, though in this instance the experiment was on a dead one.