History of the Peloponnesian War

During the same winter the Plataeans, who were still[*](For previous discussion of this siege, see ii. lxxi.-lxxviii.) being besieged by the Peloponnesians and the Boeotians, began to be distressed by failure of their supply of food, and since there was no hope of aid from Athens nor any other means of safety in sight, they and the Athenians who were besieged with them planned to leave the city and climb over the enemy's walls, in the hope that they might be able to force a passage. The attempt was suggested to them by Theaenetus son of Tolmides, a soothsayer, and Eupompidas son of Daïmachus, who was one of the generals.

At first all were to take part, but afterwards half of them somehow lost heart, thinking the risk too great, and only about two hundred and twenty voluntarily persisted in making the sortie, which was carried out in the following way.

They made ladders equal in height to the enemy's wall, getting the measure by counting the layers of bricks at a point where the enemy's wall on the side facing Plataea happened not to have been plastered over. Many counted the layers at the same time, and while some were sure to make a mistake, the majority were likely to hit the true count, especially since they counted time and again, and, besides, were at no great distance, and the part of the wall they wished to see was easily visible.

The measurement of the ladders, then, they got at in this way, reckoning the measure from the thickness of the bricks.