So great a number of ships had never before met in any action between Greeks and Greeks. The onset was vigorous; and the battle was maintained, on either side, with much courage but little skill. Both Corcyræan and Corinthian ships were equipped in the ancient manner, very inartificially. The decks were crowded with soldiers, some heavy-armed, some with missile weapons; and the action, in the eye of the Athenians, trained in the discipline of Themistocles, resembled a battle of infantry rather than a sea-fight. Once engaged, the number and throng of the vessels made free motion impossible: nor was there any attempt at the rapid evolution of the diecplus, as it was called, for piercing the enemy’s line and dashing away his oars, the great objects of the improved naval tactics; but the event depended, as of old, chiefly upon the heavy-armed soldiers who fought on the decks. Tumult and confusion thus prevailing everywhere, Lacedæmonius, restrained by his orders from fighting, gave yet some assistance to the Corcyræans, by showing himself wherever he saw them particularly pressed, and alarming their enemies. The Corcyræans were, in the left of their line, successful: twenty of their ships put to flight the Megarians and Ambracians who were opposed to them, pursued to the shore, and, debarking, plundered and burnt the naval camp. But the Corinthians, in the other wing, had meanwhile been gaining an advantage which became decisive through the imprudent forwardness of the victorious Corcyræans. The Athenians now endeavoured, by more effectual assistance to their allies, to prevent a total rout; but disorder was already too prevalent, and advantage of numbers too great against them. The Corinthians pressed their success; the Corcyræans fled, the Athenians became mingled among them; and in the confusion of a running fight acts of hostility passed between the Athenians and Corinthians. The defeated however soon reached their own shore, whither the conquerors did not think proper to follow.
In the action several galleys had been sunk; most by the Corinthians, but some by the victorious part of the Corcyræan fleet. The crews had recourse, as usual, to their boats; and it was common for the conquerors, when they could seize any of these, to take them in tow and make the men prisoners: but the Corinthians, in the first moment of success, gave no quarter; and, unaware of the disaster of the right of their fleet, in the hurry and confusion of the occasion, not easily distinguishing between Greeks and Greeks, inadvertently destroyed many of their unfortunate friends. When pursuit ceased, and they had collected whatever could be recovered of the wrecks and the dead, they carried them to a desert harbour, not distant, on the Thesprotian coast, called, like the neighbouring islets, Sybota: and depositing them under the care of their barbarian allies, who were there encamped, they returned, on the afternoon of the same day, with the purpose of renewing attack upon the Corcyræan fleet.
The Corcyræans meanwhile had been considering the probable consequences of leaving the enemy masters of the sea. They dreaded descents upon their island, and consequent ravage of their lands. The return of their victorious squadron gave them new spirits: Lacedæmonius encouraged them with assurance that, since hostilities had already passed, he would no longer scruple to afford them his utmost support; and they resolved upon the bold measure of quitting their port and, though evening was already approaching, again giving the enemy battle. Instantly they proceeded to put this in execution. The pæan, the song of battle, was already sung, when the Corinthians began suddenly to retreat. The Corcyræans were at a loss immediately to account for this; but presently they discovered a squadron coming round a headland, which had concealed it longer from them than from the enemy. Still uncertain whether it might be friendly or hostile, they also retreated into their port; but shortly, to their great joy, twenty triremes under Glaucon and Andocides, sent from Attica, in the apprehension that the small force under Lacedæmonius might be unequal to the occurring exigencies, took their station by them.