At last, perceiving that he was wasting his strength to no purpose, he changed his method of attack, and leaving his car in charge of a squire prepared to lead the assault on foot. Some time was lost while he was collecting a picked body of men to follow him, and instructing them how to proceed; and while he was taking his measures, Asius, a captain of the allies, made a bold attempt to carry the Greek position at a single blow. Disregarding Hector's orders, he remained in his chariot, called to his troop to keep close behind him, and drove rapidly round the line of the wall, looking for a weak point where he might hope to force an entrance. He succeeded beyond his hopes; for on the extreme left of the camp he found a gate which was still open to admit any stragglers who might have been left behind in the flight of the Greeks. With a shout of triumph he drove straight at the open gateway, with all his company following pell-mell. But just as he was about to cross the portals he found himself confronted by a pair of gigantic brothers, who stood like two mighty oaks deep-rooted on a mountain top, ready to dispute the way. They were well supported by the defenders who lined the walls, and a hail of stones and javelins rattled down on the shields of Asius and his men, who were driven back with loss and compelled to retire out of range. The gates were then closed and barred, and for this time the camp was saved. Meanwhile the Trojans under Hector's command were still hesitating on the brink of the moat. For a strange portent had occurred, which gave them pause, just as they were rushing to the assault. On the left hand of the army they saw an eagle soaring high in the air, holding a huge serpent in his talons, which writhed and struggled to escape. And indeed the eagle had met his match, for suddenly the serpent drew back his head, and darting forward bit his captor in the breast. The eagle gave a scream of pain, and dropping the serpent, which fell in the midst of the Trojans, flew swiftly away. All stood amazed, and doubt and fear crept into their hearts when they saw the monster writhing at their feet. At last Polydamas, a warrior who was famed for his skill in augury, turned to Hector, and said: "My prince, the sign is against us; and as the eagle was stricken, when he strove to carry the dappled snake to his young, so shall we also be stricken, if we persist in our assault on the Grecian stronghold. Let us draw off our men, lest we be found fighting against the gods, and bring upon ourselves rout and disaster."