Now all the time that the Peloponnesians were in the Athenian territory, and the Athenians were engaged in the expedition on board their ships, the plague was carrying them off both in the armament and in the city, so that it was even said that the Peloponnesians, for fear of the disorder, when they heard from the deserters that it was in the city, and also perceived them performing the funeral rites, retired the quicker from the country. Yet in this invasion they stayed the longest time, and ravaged the whole country: for they were about forty days in the Athenian territory.
The same summer Hagnon, son of Nicias, and Cleopompus, son of Clinias, who were colleagues with Pericles, took the army which he had employed, and went straightway on an expedition against the Chalcidians Thrace-ward, and Potidæa, which was still being besieged: and on their arrival they brought up their engines against Potidæa, and endeavoured to take it by every means. But they neither succeeded in capturing the city, nor in their other measures, to any extent worthy of their preparations: for the plague attacked them, and this indeed utterly overpowered them there, wasting their force to such a degree, that even the soldiers of the Athenians who were there before were infected with it by the troops which came with Hagnon, though previously they had been in good health. Phormion, however, and his sixteen hundred, were no longer in the neighbourhood of the Chalcidians (and so escaped its ravages). Hagnon therefore returned with his ships to Athens, having lost by the plague fifteen hundred out of four thousand heavy-armed, in about forty days. The soldiers who were there before still remained in the country, and continued the siege of Potidæa.
After the second invasion of the Lacedæmonians, the Athenians, when their land had been again ravaged, and the disease and the war were afflicting them at the same time, changed their views, and found fault with Pericles, thinking that he had persuaded them to go to war, and that it was through him that they had met with their misfortunes; and they were eager to come to terms with the Lacedæmonians. Indeed they sent ambassadors to them, but did not succeed in their object. And their minds being on all sides reduced to despair, they were violent against Pericles. He therefore, seeing them irritated by their present circumstances, and doing everything that he himself expected them to do, called an assembly, (for he was still general) wishing to cheer them, and by drawing off the irritation of their feelings to lead them to a calmer and more confident state of mind.
The Lacedæmonians and their allies the same summer made an expedition with a hundred ships against the island of Zacynthus, which lies over against Elis. The inhabitants are a colony of the Achæans of the Peloponnesus, and were in alliance with the Athenians. On board the fleet were a thousand heavy-armed of the Lacedæmonians, and Cnemus, a Spartan, as admiral. Having made a descent on the country, they ravaged the greater part of it; and when they did not surrender, they sailed back home.
At the end of the same summer, Aristeus, a Corinthian, Aneristus, Nicolaus, and Stratodemus, ambassadors of the Lacedæmonians, Timagoras, a Tegean, and Pollis, an Argive in a private capacity, being on their way to Asia, to obtain an interview with the king, if by any means they might prevail on him to supply money and join in the war, went first to Thrace, to Sitalces the son of Teres, wishing to persuade him, if they could, to withdraw from his alliance with the Athenians. He gave orders to deliver them up to the Athenian ambassadors; who, having received them, took them to Athens. On their arrival the Athenians, being afraid that if Aristeus escaped he might do them still more mischief (for even before this he had evidently conducted all the measures in Potidæa and their possessions Thrace-ward) without giving them a trial, though they requested to say something in their own defence, put them to death that same day, and threw them into pits; thinking it but just to requite them in the same way as the Lacedæmonians had begun with; for they had killed and thrown into pits the merchants, both of the Athenians and their allies, whom they had taken on board trading vessels about the coast of the Peloponnesus. Indeed all that the Lacedæmonians took on the sea at the beginning of the war, they butchered as enemies, both those who were confederates of the Athenians and those who were neutral.