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.
the Athenians. It would be wise, therefore, with their allies that were still left, to oppose the Syracusans, especially as the Egestaeans would furnish money sufficient for the war. And the Athenians, hearing in their assemblies these arguments of the Egestaeans and their supporters, who constantly repeated them, voted first to send envoys to Egesta to see whether the money was on hand, as they said, in the treasury and in the temples, and at the same time to ascertain how matters stood with reference to the war with the Selinuntians.
Accordingly the Athenian envoys were despatched to Sicily. But during the same winter the Lacedaemonians and their allies, except the Corinthians, invaded the Argive territory, ravaged a small part of the land and carried off some corn in wagons which they had brought with them; then having settled the Argive fugitives at Orneae, leaving with them also a small body of troops, after they had made a truce for a certain time, on condition that the Orneates and Argives were not to injure one another's land, they went home with the rest of their force.
When the Athenians came not long afterwards with thirty ships and six hundred hoplites, the Argives, in company with the Athenians, went out in full force and besieged the garrison at Orneae for a single day; but under cover of night, when the besieging army had bivouacked at a distance, the garrison of Orneae escaped.