"Animated by this trifling success, he proceeded with fresh ardour, and the rapidity of his progress was proclaimed by the heap of bricks, stones, and mortar, which before long covered the floor. At the expiration of an hour, by dint of unremitting exertion, he made so large a breach in the chimney that he could stand upright in it. He was now within a foot of the bar, and introducing himself into the hole, he speedily worked his way to it. Regardless of the risk he ran by some heavy stones dropping on his head or feet,--regardless also of the noise made by the falling rubbish, and of the imminent risk to which he was consequently exposed of being interrupted by some of the gaolers, should the sound reach their ears, he continued to pull down large masses of the wall, which he flung upon the floor of the cell. Having worked thus for another quarter of an hour, without being sensible of fatigue, though he was half stifled by the clouds of dust which his exertions raised, he had made a hole about three feet wide and six high, and uncovered the iron bar. Grasping it firmly with both hands, he quickly wrenched it from the stones in which it was mortised, and leapt to the ground. On examination it proved to be a flat bar of iron, nearly a yard in length, and more than an inch square. 'A capital instrument for my purpose,' thought Jack, shouldering it, 'and worth all the trouble I have had in procuring it.' While he was thus musing, he thought he heard the lock tried. A chill ran through his frame, and grasping the heavy weapon, with which chance had provided him, he prepared to strike down the first person who should enter his cell. After listening attentively for a short time without drawing breath, he became convinced that his apprehensions were groundless, and, greatly relieved, sat down upon the chair to rest himself and prepare for future efforts.