Before the passage commenced, the bridges were strewn with the sacred myrtle and perfumed with incense from golden censers, while the sea was placated with libations poured by the king himself. As the east reddened with the approach of day, prayers were offered, and the moment the rays of the sun touched the bridges the passage began. To avoid accidents and delays, the trains of baggage wagons and the beasts of burden crossed by one causeway, leaving the other free for the march of the army. The first of the host to cross was the sacred guard of the Great King, the Ten Thousand Immortals, all crowned with garlands as in festival procession. Preceding the king, the gorgeous Chariot of the Sun moved slowly, drawn by eight milk-white steeds. Herodotus affirms that for seven days and seven nights the bridges groaned beneath the living tide that Asia was pouring into Europe. [Footnote: According to Herodotus, the land and naval forces of Xerxes amounted to 2,317,000 men, besides about 2,000,000 slaves and attendants. It is believed that these figures are a great exaggeration, and that the actual number of the Persian army could not have exceeded 900,000 men.] BATTLE OF THERMOPYLÆ (480 B.C.).--Leading from Thessaly into Central Greece is a narrow pass, pressed on one side by the sea and on the other by rugged mountain ridges. At the foot of the cliffs break forth several hot springs, whence the name of the pass, Thermopylæ, or "Hot Gates." At this point, in accordance with the decision of the Corinthian Congress, was offered the first resistance to the progress of the Persian army. Leonidas, king of Sparta, with three hundred Spartan soldiers and about six thousand allies from different states of Greece, held the pass. As the Greeks were about to celebrate the Olympian games, which their religious scruples would not allow them to postpone, they left this handful of men unsupported to hold in check the army of Xerxes until the festival days should be past. The Spartans could be driven from their advantageous position only by an attack in front, as the Grecian fleet prevented Xerxes from landing a force in their rear. Before assaulting them, Xerxes summoned them to give up their arms. The answer of Leonidas was, "Come and take them." For two days the Persians tried to storm the pass. The Asiatics were driven to the attack by their officers armed with whips. But every attempt to force the way was repulsed; even the Ten Thousand Immortals were hurled back from the Spartan front like waves from a cliff.