The Persian army were seen covering the whole country like locusts, and the hearts of some of the southern Greeks in the pass began to sink. Their homes in the Peloponnesus were comparatively secure--had they not better fall back and reserve themselves to defend the Isthmus of Corinth? But Leonidas, though Sparta was safe below the Isthmus, had no intention of abandoning his northern allies, and kept the other Peloponnesians to their posts, only sending messengers for further help. Presently a Persian on horseback rode up to reconnoitre the pass. He could not see over the wall, but in front of it, and on the ramparts, he saw the Spartans, some of them engaged in active sports, and others in combing their long hair. He rode back to the king, and told him what he had seen. Now, Xerxes had in his camp an exiled Spartan Prince, named Demaratus, who had become a traitor to his country, and was serving as counsellor to the enemy. Xerxes sent for him, and asked whether his countrymen were mad to be thus employed instead of fleeing away; but Demaratus made answer that a hard fight was no doubt in preparation, and that it was the custom of the Spartans to array their hair with special care when they were about to enter upon any great peril. Xerxes would, however, not believe that so petty a force could intend to resist him, and waited four days, probably expecting his fleet to assist him, but as it did not appear, the attack was made. The Greeks, stronger men and more heavily armed, were far better able to fight to advantage than the Persians, with their short spears and wicker shields, and beat them off with great ease. It is said that Xerxes three times leapt off his throne in despair at the sight of his troops being driven backwards; and thus for two days it seemed as easy to force a way through the Spartans as through the rocks themselves. Nay, how could slavish troops, dragged from home to spread the victories of an ambitious king, fight like freemen who felt that their strokes were to defend their homes and children! But on that evening a wretched man, named Ephialtes, crept into the Persian camp, and offered, for a great sum of money, to show the mountain path that would enable the enemy to take the brave defenders in the rear! A Persian general, named Hydarnes, was sent off at nightfall with a detachment to secure this passage, and was guided through the thick forests that clothed the hillside. In the stillness of the air, at daybreak, the Phocian guards of the path were startled by the crackling of the chestnut leaves under the tread of many feet. They started up, but a shower of arrows was discharged on them, and forgetting all save the present alarm, they fled to a higher part of the mountain, and the enemy, without waiting to pursue them, began to descend.