While the allies were thus engaged at Decelea, a considerable body of troops had embarked at Taenarum and at Corinth, and sailed to take part in the defence of Syracuse. In Greece, all the old enemies of Athens were arming against her, and beyond the sea her prospects grew darker and darker every day. Yet nothing, it seemed, could break the spell of fatal delusion which rested on the doomed city. While Attica lay in the grip of the enemy, a fleet of sixty-five triremes, carrying a great military force, weighed anchor from Peiraeus, and steered its course, under the command of Demosthenes, for Sicily. VIII We must now return to Syracuse, where fortune was preparing a new blow for the ill-fated Athenian army. Gylippus came back from his mission at the beginning of spring, bringing with him the reinforcements which he had gathered from various parts of Sicily. At once resuming the offensive, he planned an attack on the forts recently erected by Nicias at Plemmyrium, and in order to divide the attention of the Athenians, he determined to make a simultaneous movement against them by sea and land. He himself took command of the army, and setting out at night, made his way round to the rear of the Athenian position at Plemmyrium. Meanwhile the Syracusan fleet lay ready in two divisions, one of which, consisting of thirty-five vessels, was moored in the docks, within the Great Harbour, while the other, to the number of forty-five, had its station in the Lesser Harbour. At the hour appointed by Gylippus, just as day was breaking, both squadrons got under weigh, and bore down upon Plemmyrium, from the opposite sides of Ortygia. Though taken by surprise, the Athenians put out in haste with sixty triremes, and a sea-fight ensued, in which the Syracusans for some time had the advantage. By this time Gylippus was at hand with his army, and by a sudden assault on the Athenian forts he made an easy capture of all three; for the greater part of the garrison had flocked down to the sea, to watch the progress of the action in the Great Harbour. Fortunately for these men, who had so grossly neglected their duty, the Athenian fleet had now gained a decisive victory, and they were thus enabled to make their escape by water, and cross over to the camp of Nicias, on the other side of the bay. By the capture of Plemmyrium a great treasure fell into the hands of the Syracusans. The loss to the Athenians, in money, stores, and men, was serious enough; but further consequences ensued, which were nothing less than disastrous. The enemy now commanded both sides of the entrance to the Great Harbour, and not a ship-load of provisions could reach the Athenian camp without an encounter with the Syracusan triremes. Well might despondency and dismay take possession of the beleaguered army, cramped in their narrow quarters on the swampy flats of the Anapus.