History of the Peloponnesian War

Nicias delivered this exhortation to them, and immediately commanded them to man the ships. Gylippus and the Syracusans, on the other hand, were able to perceive, from the sight of their very preparations, that the Athenians were about to engage them at sea, and the device of throwing the grappling irons had also been previously reported to them.

They prepared themselves therefore on all other points severally, and on this also; for they covered over with hides their prows and a considerable space of the upper part of the vessel, so that the grapple, when thrown, might slip off, and not obtain any hold on them.