The Conduct of the Greeks. - The Oracle relating to Salamis. - Art of Themistocles. - The Isthmian Congress. - Embassies to Argos, Crete, Corcyra, and Syracuse. - Their ill Success. - The Thessalians send Envoys to the Isthmus. - The Greeks advance to Tempe, but retreat. - The Fleet despatched to Artemisium, and the Pass of Thermopylae occupied. - Numbers of the Grecian Fleet. - Battle of Thermopylae.