The Eight Books of Thucydides' History, translated by R. Crawley.
Aware of this, the Athenian generals determined to draw them out in mass as far as possible from the city, and themselves in the meantime to sail by night alongshore, and take up at their leisure a convenient position. This they knew they could not so well do, if they had to disembark from their ships in front of a force prepared for them, or to go by land openly. The numerous cavalry of the Syracusans (a force which they were themselves without) would then be able to do the greatest mischief to their light troops and the crowd that followed them; but this plan would enable them to take up a position in which the horse could do them no hurt worth speaking of, some Syracusan exiles with the army having told them of the spot near the Olympieum, which they afterwards occupied. In pursuance of their idea, the generals imagined the following stratagem. They sent to Syracuse a man devoted to them, and by the Syracusan generals thought to be no less in their interest; he was a native of Catana, and said he came from persons in that place, whose names the Syracusan generals were acquainted with, and whom they knew to be among the members of their party still left in the city. He told them that the Athenians passed the night in the town, at some distance from their arms, and that if the Syracusans would name a day and come with all their people at daybreak to attack the armament, they, their friends, would close the gates upon the troops in the city, and set fire to the vessels, while the Syracusans would easily take the camp by an attack upon the stockade. In this they would be aided by many of the Catanians, who were already prepared to act, and from whom he himself came.
The generals of the Syracusans, who did not want confidence, and who had intended even without this to march on Catana, believed the man without any sufficient inquiry, fixed at once a day upon which they would be there, and dismissed him, and the Selinuntines and others of their allies having now arrived, gave orders for all the Syracusans to march out in mass. Their preparations completed, and the time fixed for their arrival being at hand, they set out for Catana, and passed the night upon the river Symaethus, in the Leontine territory. Meanwhile the Athenians no sooner knew of their approach than they took all their forces and such of the Sicels or others as had joined them, put them on board their ships and boats, and sailed by night to Syracuse. Thus, when morning broke the Athenians were landing opposite the Olympieum ready to seize their camping ground, and the Syracusan horse having ridden up first to Catana and found that all the armament had put to sea, turned back and told the infantry, and then all turned back together, and went to the relief of the city.
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