History of the Peloponnesian War

Now when several had got up, the sentinels on the towers became aware of their presence; for one of the Plataeans in laying hold of the battlements threw down a tile, which fell with a thud.

And immediately there was an outcry, and the garrison rushed to the wall; for they did not know what the danger was, as the night was dark and stormy, and at the same time the Plataeans who had been left behind in the town went out and attacked the wall of the Peloponnesians on the side opposite that over which their men were climbing, to distract attention from them as far as possible.

Now the sentinels remained at their posts, though in a state of excitement, no one daring to leave his station and lend aid, but all being at a loss to conjecture what was going on.

Furthermore, the three hundred, who had been appointed to bring aid wherever it was needed, proceeded outside of the wall in the direction of the outcry, and beacon fires indicating danger from the enemy were flashed towards Thebes.

But the Plataeans in the town at the same time raised from their wall many deacons, which had been prepared beforehand for this very purpose, that the enemy's beacon signals might be rendered unintelligible and that the Thebans, thinking that the situation was different from what it really was, might defer bringing aid until the Plataeans who were leaving should have made good their escape and reached safety.