Hermocrates the Syracusan suspected their intention, and dreading what might happen if1
their vast army, retreating by land and settling somewhere in Sicily, should choose to renew the war, he went to the authorities, and represented to them that they ought not to allow the Athenians to withdraw by night (mentioning his own suspicion of their intentions), but that all the Syracusans and their allies should go out in advance, wall up the roads, and occupy the passes with a guard.
They thought very much as he did, and wanted to carry out his plan, but doubted whether their men, who were too glad to repose after a great battle, and in time of festival—for there happened on that very day to be a sacrifice to Heracles—could be induced to obey. Most of them, in the exultation of victory, were drinking and keeping holiday, and at such a time how could they ever be expected to take up arms and go forth at the order of the generals? On these grounds the authorities decided that the thing was impossible.
Whereupon Hermocrates himself, fearing lest the Athenians should gain a start and quietly pass the most difficult places in the night, contrived the following plan: when it was growing dark he sent certain of his own acquaintance, accompanied by a few horsemen, to the Athenian camp. They rode up within earshot, and pretending to be friends (there were known to be men in the city who gave information to Nicias of what went on)2
called to some of the soldiers, and bade them tell him not to withdraw his army during the night, for the Syracusans were guarding the roads; he should make preparation at leisure and retire by day.
Having delivered their message they departed, and those who had heard them informed the Athenian generals.