Driscoll was sorting pit-props, throwing them on to piles at the bottom of the shaft, when Thirlwell stopped to hook a small, flat lamp to his hat. The man sometimes worked in the mine for a few weeks when the trapping season was over, and Scott was generally willing to engage him because he was skilful with the axe and labor was scarce. He made no friends among the men, and gave Thirlwell a sour look without speaking when the latter picked up his lamp. Thirlwell went on down the inclined gallery. Water splashed upon his slickers and trickled about his feet; the tunnel was narrow and the air was foul. Here and there a smoky light burned among the props lining the walls, and the dim illumination touched the beams that crossed the roof, but the gaps between the spots were dark. The timbers were numerous, and where one could see a short distance, ran on into the gloom in rows so closely spaced that they seemed continuous. By and by Thirlwell found Scott looking up at a massive beam a few inches overhead. The beam was not quite level, and the prop beneath one end had bent, while a threatening crack extended across the roof. "We may have a bad fall here," Scott remarked. "The prop's getting shaky and the pressure's pretty fierce. I reckon we'd better shore her up as quick as we can. It's lucky our lumber doesn't cost us much." Thirlwell examined the crack and thought it dangerous. There were one or two transverse splits, which indicated a heavy mass of rock was ready to come down. None of the men were near the spot, and he knew they were occupied, but Driscoll had left a few props between the timbers, ready for use where the roof was weak. Thirlwell found one and dragged it to the spot. "We'll put this up and then I think I'll get a fresh beam across." Scott helped him to raise the timber. It was a few inches too long, and crossed the space between floor and roof with a small slant, but it was meant to do so, in order that when its lower end was driven forward until it stood upright it would wedge fast the beam above. Then Thirlwell brought an ax and struck the prop some heavy blows with its back while Scott steadied the top. It was almost in place, and the bent timber was getting loose, when the top slipped and shook the beam. There was an ominous crack and a few small stones broke away and fell on Scott's head. "I've got her butted solid now," he shouted after a short breathless struggle with the timber. "Be quick! The roof's coming down!"