When Mardonius invaded Attica a second time, the Athenians again took refuge in Salamis.  Aristeides was sent to Lacedaemon and upbraided the Spartans with their slowness and indifference, for allowing the enemy to take Athens a second time, and begged them to help what remained of Greece.  The Ephors, on hearing this, pretended to pass the rest of the day in feasting and idleness, for it was the festival of the Hyacinthia; but at nightfall they chose five thousand Spartans, each attended by seven Helots, and sent them off without the knowledge of the Athenian embassy.  So when Aristeides next day resumed his reproachful strain, they answered with mocking laughter, that he was talking nonsense and was asleep, for that the army was by this time at the tomb of Orestes in its march against the strangers[22] (by strangers they meant the Persians).  To this Aristeides answered that it was a sorry jest to have deceived their friends instead of their enemies.  These particulars are related by Idomeneus, but in the decree of Aristeides for sending ambassadors it is not his name, but those of Kimon, Xanthippus, and Myronides that are mentioned.

XI.  He was elected general with unlimited powers, and proceeded to Plataea with eight thousand Athenians.  Here he was met by Pausanias, the commander-in-chief of the Greek forces, with the Spartan contingent, and the rest of the Greek troops joined them there.  The Persian army was encamped along the course of the river Asopus.  On account of its enormous size it was not contained in a fortified camp, but a quadrangular wall was constructed round the baggage and most valuable material.  Each side of this square was ten furlongs in length.

Tisamenus of Elis, the prophet, now told Pausanias and all the Greeks that they would win the victory if they stood on the defensive and did not attack.  Aristeides sent to Delphi, and received a response from the oracle, that the Athenians would conquer if they prayed to Zeus, to Hera of Kithaeron, and to Pan and the nymphs Sphragitides, and if they sacrificed to the heroes Androkrates, Leukon, Peisander, Damokrates, Hypsion, Aktaion, and Polyidus, and if they would fight in their own territory, in the plain of Demeter of Eleusis and her daughter.

This oracle greatly disturbed Aristeides.  The heroes to whom he was bidden to sacrifice are the original founders of the city of Plataea, and the cave of the nymphs called Sphragitides, is on one of the peaks of Kithaeron, looking towards the point where the sun sets in summer.  It is said that there was formerly an oracle there, and that many of the people became possessed, and were called “nympholeptae.”  But as to the plain of the Eleusinian Demeter, and the promise of victory to the Athenians if they fought in their own country, this meant no less than to recall them to Attica and forbid their taking any further part in the war.  Whilst Aristeides was thus perplexed, Arimnestus, the general of the Plataeans, saw a vision