History of the Peloponnesian War

"Athenians, you know by many other my letters what hath passed formerly; nor is it less needful for you to be informed of the state we are in, and to take counsel upon it, at this present.

When we had in many battles beaten the Syracusians, against whom we were sent, and had built the walls within which we now lie, came Gylippus a Lacedaemonian, with an army out of Peloponnesus, and also out of some of the cities of Sicily, and in the first battle was overcome by us; but in the second, forced by his many horsemen and darters, we retired within our works.

Whereupon giving over our walling up of the city for the multitude of our enemies, we now sit still. Nor can we indeed have the use of our whole army, because some part of the men of arms are employed to defend our walls. And they have built a single wall up to us, so that now we have no more means to enclose it, except one should come with a great army and win that cross wall of theirs by assault.

And so it is that we who seemed to besiege others are besieged ourselves for so much as concerneth the land; for we cannot go far abroad by reason of their cavalry.