History of the Peloponnesian War

The Boeotians replied that if they were in Boeotia, they must evacuate that country before taking up their dead; if they were in their own territory, they could do as they pleased: for they knew that, although the Oropid where the bodies as it chanced were lying (the battle having been fought on the borders) was subject to Athens, yet the Athenians could not get them without their leave. Besides, why should they grant a truce for Athenian ground? And what could be fairer than to tell them to evacuate Boeotia if they wished to get what they asked? The Athenian herald accordingly returned with this answer, without having accomplished his object.

Meanwhile the Boeotians at once sent for darters and slingers from the Malian gulf, and with two thousand Corinthian heavy infantry who had joined them after the battle, the Peloponnesian garrison which had evacuated Nisaea, and some Megarians with them, marched against Delium, and attacked the fort, and after divers efforts finally succeeded in taking it by an engine of the following description.

They sawed in two and scooped out a great beam from end to end, and fitting it nicely together again like a pipe, hung by chains a cauldron at one extremity, with which communicated an iron tube projecting from the beam, which was itself in great part plated with iron.

This they brought up from a distance upon carts to the part of the wall principally composed of vines and timber, and when it was near, inserted huge bellows into their end of the beam and blew with them.