History of the Peloponnesian War

But the Athenians (being distressed by the plague and the war, which had so recently broken out and was now at its height) thought it a serious business to incur the additional hostility of Lesbos, with her fleet and power hitherto unimpaired; and were not at first disposed to listen to the charges, allowing too much weight to their wish that it might not be true. When, however, they had even sent ambassadors without prevailing on the Mytilenaeans to stop their measures for the union and their preparations, they were alarmed, and wished to reduce them by surprise.

Accordingly they despatched with all haste forty ships that happened to have been equipped for cruising round the Peloponnese, under the command of Cleïppides son of Dinias, and two colleagues.