"There must be something, somewhere," said Andrew, against reason. Again his eyes slowly traversed the familiar walls of the room from ceiling to floor. Then he stiffened all over like a dog coming to point. High up in the wall and hardly visible in the gloom, beyond the reach of their hands, was a large, projecting nail. "Get up on my shoulders, Sebastian--there is our tool," he said, his voice shaken as if he had just risen from deep water with a sea-pearl in his hand. It took an hour or so to work the nail loose from the wall. When they had it down at last, it proved bent and rusty but they gloated over it with a solemn joy. "Now," said Sebastian, practically, "Where?" and he looked around him. "We could never tunnel through from below in time," said Andrew. "That stone beneath the window--can you reach it, if you stand on my shoulders again?" "I can just reach up to the middle of the bar," said Sebastian, after he had tried. "Sentry outside?" Sebastian peered cautiously, "I don't see one. But there may be one. There's a ditch, and a little rise beyond it." "Thank God the light's gone away. He'd hardly see us, anyhow, in the darkness--and we'll just have to chance being heard. Is the window too small?" "Yes. Even if we could cut the bar." "Well then," said Andrew, gritting his teeth and wishing Sebastian weighed less. "We'll have to take out the stone." They spelled each other, all afternoon, at short intervals, the one who was below listening for the footsteps of the guard. The nail grew dull--then sharp again as it filed itself against the stone--then dull once more. Once it almost broke in two and once they were nearly caught by the unexpected return of the corporal soon after he had brought them a scant and nasty dinner. It was hard, exhausting work--the mortar at which they picked was only a little less indurate than the stones it cemented and the man who worked had to support himself with one hand against the wall while his human stepladder suffered rigid agonies in back and loins. When they were too beaten with fatigue to work any more it seemed to them as if they had accomplished as little as a pair of caterpillars gnawing blindly at the sides of an iron box, but at least a beginning had been made. They disguised their work with a paste of mud and spittle and rested achingly. The next day was the same, and the next--a fever of labor in the dark to the accompaniment of the slight rasp of the worn nail against the stone--a driving of cramped, rebellious muscles to the same monotonous, tiny task. Pick, pick, pick, went the sound of the nail--pick, pick, pick. The sound wore a shallow groove in Andrew's mind. He could hear it continue interminably through the uneasy veil of sleep and his fingers twitched mechanically as if they still held the nail.