The assistance given by Athens to the Ionian revolt stirred the wrath of the Persian monarch very deeply, and when he had put down the rebellion he prepared to chastise the audacious and insolent Greeks. "A great fleet started from the Hellespont, with orders to sail round the peninsula of Mt. Athos to the Gulf of Therma, while Mardonius advanced by land. His march was so harassed by the Thracians that when he had effected the conquest of Macedonia his force was too weak for any further attempt. The fleet was overtaken by a storm off Mt. Athos, on whose rocks 300 ships were dashed to pieces, and 20,000 men perished. Mardonius returned in disgrace to Asia with the remnant of his fleet and army. This failure only added fury to the resolution of Darius. While preparing all the resources of his empire for a second expedition, he sent round heralds to the chief cities of Greece, to demand the tribute of earth and water as signs of his being their rightful lord. Most of them submitted: Athens and Sparta alone ventured on defiance. Both treated the demand as an outrage which annulled the sanctity of the herald's person. At Athens the envoy was plunged into the loathsome Barathrum, a pit into which the most odious public criminals were cast. At Sparta the herald was hurled into a well, and bidden to seek his earth and water there. The submission of Ægina, the chief maritime state of Greece, and the great enemy of Athens, entailed the most important results. The act was denounced by Athens as treason against Greece, and the design was imputed to Ægina of calling in the Persians to secure vengeance on her rival. The Athenians made a formal complaint to Sparta against the 'Medism' of the Æginetans; a charge which is henceforth often repeated both against individuals and states. The Spartans had recently concluded a successful war with Argos, the only power that could dispute her supremacy in Peloponnesus; and now this appeal from Athens, the second city of Greece, at once recognized and established Sparta as the leading Hellenic state. In that character, her king Cleomenes undertook to punish the Medizing party in Ægina 'for the common good of Greece'; but he was met by proofs of the intrigues of his colleague Demaratus in their favour. … Cleomenes obtained his deposition on a charge of illegitimacy, and a public insult from his successor Leotychides drove Demaratus from Sparta. Hotly pursued as a 'Medist,' he effected his escape to Darius, whose designs against Athens and Sparta were now stimulated by the councils of their exiled sovereigns, Hippias and Demaratus. Meanwhile, Cleomenes and his new colleague returned to Ægina, which no longer resisted, and having seized ten of her leading citizens, placed them as hostages in the hands of the Athenians. Ægina was thus