Demosthenes saw at once that, before any progress could be made with the siege of Syracuse, it was necessary to gain possession of the counterwall, and confine the Syracusans within the limits of their city. The sooner he made the attempt, the greater was his chance of success; for every day wasted would give new confidence to the enemy, and the condition in which he found the troops of Nicias was a visible warning against the fatal consequences of delay. An attack made on the cross-wall from its southern side ended in total failure; his siege-engines were burnt, and the storming-parties repulsed at every point. The only course which remained was to march round to the north-western extremity of the plateau, carry the fort of Euryelus, and assail the Syracusans within their own lines. After consulting with his colleagues, Demosthenes determined to try the hazardous method of a night-attack, hoping thus to take the garrison on Euryelus by surprise. He himself, with Eurymedon and Menander, took the command, and the whole Athenian army was engaged in the adventure, except those who remained behind with Nicias to guard the camp. On a moonlight night in August, at the hour of the first watch, the march began. Moving cautiously up the valley of the Anapus, they turned the northern end of the hill, and reached the path by which Lamachus had ascended in the spring of the previous year. At first all seemed to promise success to the Athenians unobserved by the enemy, Demosthenes ascended the hill, stormed the fort, and, drove the garrison back on the three fortified camps which flanked the Syracusan counterwall on its northern side. The fugitives raised the alarm, and the call was promptly answered by a picked troop of six hundred hoplites, who were stationed nearest to the point of danger. These men made a gallant stand, but they were overpowered by superior numbers, and thrust back on the main body of the Syracusans, who were now advancing under Gylippus to the rescue. They in their turn were forced to give ground before the impetuous charge of Demosthenes, and a general panic seemed about to spread through the whole Syracusan army. Already the Athenians had begun to throw down the battlements of the counterwall, and if they were allowed to proceed, Syracuse would once more be exposed to imminent danger.