Fourth year of the war—internal suffering at Athens.—Renewed invasion of Attica.—Revolt of Mitylênê and most part of Lesbos from Athens.—Proceedings of Athens—powerful condition of Mitylênê—Athenian fleet sent thither under Kleïppidês.—Kleïppidês fails in surprising Mitylênê—carries on an imperfect blockade.—He receives reinforcements, and presses the siege with greater vigor—want of resolution on the part of the Mitylenæans.—The Mitylenæan envoys address themselves to the Spartans at the Olympic festival, entreating aid.—Tone and topics of their address.—Practical grounds of complaint on the part of the Mitylenæans against Athens few or none.—The Peloponnesians promise assistance to Mitylênê—energetic demonstrations of the Athenians.—Asôpius son of Phormio in Akarnania.—The accumulated treasure of Athens exhausted by her efforts—necessity for her to raise a direct contribution.—Outbreak of the Platæans from their blockaded town.—Their plan of escape—its extraordinary difficulty and danger. Half of the garrison of Platæa escapes to Athens.—Blockade of Mitylênê closely carried on by the Athenian general Pachês—the Mitylenæans are encouraged to hold out by the Lacedæmonians, who send thither Salæthus.—Mitylênê holds out till provisions are exhausted—Salæthus arms all the people of Mitylênê for a general sally—the people refuse to join—the city is surrendered to Athens, at discretion.—The Peloponnesian fleet under Alkidas arrives off the coast of Ionia—astonishment and alarm which its presence creates.—Pachês, after the capture of Mitylênê, pursues the fleet of Alkidas, which returns to Peloponnesus without having done anything.—Pachês at Notium—he captures the place—his perfidy towards Hippias, the leader of the garrison.—Notium recolonized from Athens as a separate town.—Pachês sends to Athens about a thousand Mitylenæan prisoners, the persons chiefly concerned in the late revolt, together with Salæthus.—Important debate in the Athenian assembly upon the treatment of the prisoners.—First mention of Kleon by Thucydidês—new class of politicians to which he belonged.—Eukratês, Kleon, Lysiklês, Hyperbolus, etc.—Character of Kleon.—Indignation of the Athenians against Mitylênê—proposition of Kleon to put to death the whole male population of military age is carried and passed.—Repentance of the Athenians after the decree is passed. A fresh assembly is convened to reconsider the decree.—Account of the second assembly given by Thucydidês—speech of Kleon in support of the resolution already passed.—Remarks on the speech of Kleon.—Speech of Diodotus in opposition to Kleon—second decree mitigating the former. Rapid voyage of the trireme which carries the second decree to Mitylênê—it arrives just in time to prevent the execution of the first.—Those Mitylenæans whom Pachês had sent to Athens are put to death—treatment of Mitylênê by the