In the beginning of the third campaign, Marcellus, almost absolutely despairing of being able to take Syracuse by force, because Archimedes continually opposed him with invincible obstacles, or by famine, because the Carthaginian fleet, which was returned more numerous than before, easily threw in convoys, deliberated whether he should remain before Syracuse, or direct his endeavours against Agrigentum. But before he came to a final determination, he thought it proper to try whether he could not make himself master of Syracuse by some secret intelligence. There were many Syracusans in his camp, who had taken refuge there in the beginning of the troubles. A slave of one of these secretly carried on an intrigue in which four score of the principal persons were concerned, who came in companies to consult with him in the camp, concealed in barks, under the nets of fishermen. The conspiracy was on the point of taking effect, when a person named Attalus, through resentment for not having been admitted into it, discovered the whole to Epicydes, who put all the conspirators to death. This enterprise having thus miscarried, Marcellus found himself in new difficulties. He was filled with grief and shame at the idea of raising a siege which had consumed so much time, and cost the republic so many men and ships. An accident, however, supplied him with a resource, and gave a new life to his hopes. Some Roman vessels had taken one Dæmippus, whom Epicydes had sent to negotiate with Philip, king of Macedon. The Syracusans expressed a great desire to ransom this man, and Marcellus was not averse to it. A place near the port of Trozilus was fixed upon for the conference regarding the amount. As the deputies went thither several times, it came into the mind of a Roman soldier who accompanied them to consider the wall with great attention. After having counted the stones, and examined the measure of each of them, upon a calculation of the height of the wall, he found it to be much lower than it was accounted, and concluded that with ladders of a moderate length it might be easily scaled. Without loss of time, he communicated this to Marcellus, who knew that the general is not always the only shrewd man in an army, and, taking his advice, assured himself, with his own eyes, of the fact. Having caused ladders to be prepared, he took the opportunity of a festival that the Syracusans celebrated for three days in honour of Diana, during which the inhabitants gave themselves up entirely to rejoicings and banquets. At the time of night when he conceived they would be heavy and sleepy after their debauch, he ordered a thousand chosen troops to advance with their ladders towards the wall. When the first had got to the top without disturbing the watch, others followed, encouraged by the boldness and success of their leaders. The Syracusans proved to be either drunk or asleep, and the thousand soldiers soon scaled the wall.