On the day appointed for the great task, Jason boldly approached the fire-breathing bulls, for Medea had given him a charm by which the fierce brutes were rendered harmless, and were easily yoked and harnessed to the plow. Then, in the presence of the astonished spectators, who expected to see him crushed beneath the brazen hoofs, Jason plowed the field; and having sown it with dragon's teeth, stood ready, sword in hand, to meet the attack of the giants who sprang up out of the ground clad in full armor. When he saw the glittering spears turned toward him, Jason's heart began to quail lest, after all, Medea's help should prove ineffective; and even the sorceress herself felt a momentary doubt of her own power to save her lover from his foes. As the armed men were about to rush upon him, Jason threw a stone in their midst, according to Medea's instructions, and the giants turned against each other and began a furious battle that ended in the destruction of the whole armed host. Then the hero, accompanied by Medea, hastened to the tree where the golden fleece hung, and here a charm was needed to lull to sleep the dragon that guarded the treasure. As soon as the great eyes that had never been known to close began to shut one by one, Jason stepped softly up behind the monster and cut off its head. It was but a moment's work to tear the fleece from the tree where it had hung for so many years, and to bear it in triumph to the Argo, where Jason's friends stood anxiously awaiting his coming. The men were already at the oars, for he had told them to be ready to sail at a moment's notice when he should appear bearing the golden fleece. In spite of Æetes's promise the hero did not trust him, and so made his preparations for departure very secretly. When he and Medea boarded the Argo with their prize, the rowers bent with all their strength to the oars, and the ship slid silently and swiftly out of the harbor.