Notwithstanding the obstinacy of the defence, and the cold and continual rains, the Roman soldiers surmounted all obstacles, and raised in twenty-five days a terrace 330 feet wide by 80 feet high. It already nearly touched the town wall, when, towards the third watch (midnight), clouds of smoke were seen issuing from it. It was the moment when Cæsar, according to his custom, was inspecting the works, and encouraging the soldiers at their labour; the Gauls had set the terrace on fire from the gallery of a mine. At the same instant cries arose from the whole extent of the rampart, and the besieged, rushing out by two gates, made a sally on the two sides where the towers were; from the top of the walls some threw dry wood and torches on the terrace, others pitch and various inflammable materials; nobody knew whither to run nor where to give help. As two legions, however, generally passed the night under arms in front of the camp, whilst the others relieved each other alternately for the work, they were soon able to face the enemy; meanwhile some drew back the towers, and others cut the terrace to intercept the fire; the whole army, in fact, hurried to put out the latter. When day broke, they were still fighting on every point; the besieged had the more hope of conquering, as the penthouses which protected the approaches to the towers were burnt (_deustos pluteos turrium_),[478] and as then the Romans, compelled to march without cover, could with difficulty arrive at the burning works. Persuaded that the salvation of Gaul depended on this critical moment, they replaced incessantly the troops which were weary. Then happened a fact worthy of notice: before the gate of the _oppidum_ there was a Gaul who threw balls of grease and pitch into the fire opposite a Roman tower; a dart shot from a _scorpion_[479] struck him in the right side and killed him. The next man immediately takes his place, and perishes in the same manner; a third succeeds him, then a fourth, and the post is only abandoned after the extinction of the fire and the retreat of the assailants. After so many fruitless efforts, the Gauls resolved next day to obey the order of Vercingetorix, and evacuate the place. His camp not being far off, they hoped, by favour of the night, to escape without great loss, reckoning on a continuous marsh to protect their flight. But the women, in despair, struggle to retain them, and, seeing that their supplications had no effect, to such an extent does fear extinguish pity, they give warning to the Romans by their cries, and thus compel the Gauls to renounce their intended flight.