History of the Peloponnesian War
Thucydides
Thucydides, Vol. 1-4. Smith, Charles Foster, translator. London and Cambridge, MA: Heinemann and Harvard University Press, 1919-1923.
But the Athenians, observing the closing of the harbour and being aware of the general plans of the enemy, thought it desirable to hold a council.
So the generals and the taxiarchs came together and took counsel with reference to the difficulties which now confronted them both in other ways, and especially owing to the fact that they no longer had supplies for their immediate needs—for in the expectation that they would sail away they had already sent word to Catana and stopped the bringing in of provisions—and were not likely to have them in the future, unless they should hold the mastery at sea. They determined, therefore, to abandon their upper walls,[*](ie. the upper extremity of their lines, under the bluffs of Epipolae and furthest from the harbour.) and cutting off by means of a cross-wall the smallest possible space, close to the ships, that would suffice for the stores and for the sick, to put a garrison in this: they would then take the rest of their land-force and man all their ships, not only those which were fit for service, but also the less seaworthy, putting aboard every available man, and fight the issue out at sea; if they won, they would proceed to Catana, but if not, they would burn their ships, and, forming in line of battle, make their retreat by land, taking whatever route would enable them soonest to reach some friendly place, whether Barbarian or Hellenic.
These plans having once been determined upon, they acted accordingly: they descended stealthily from the upper walls and manned all their ships, compelling everyone to embark who, provided lie was of military age, seemed to be at all fit for service.