History of the Peloponnesian War

Meanwhile the party opposed to the traitors proved numerous enough to prevent the gates being immediately thrown open, and in concert with Eucles, the general, who had come from Athens to defend the place, sent to the other commander in Thrace, Thucydides, son of Olorus, the author of this history, who was at the isle of Thasos, a Parian colony, half a day's sail from Amphipolis, to tell him to come to their relief.

On receipt of this message he at once set sail with seven ships which he had with him, in order, if possible, to reach Amphipolis in time to prevent its capitulation, or in any case to save Eion.