This mine's vein (or the vein-shaped cavity where the vein had once been) was close to the surface and so there was no need to descend numerous ladders in some deep shaft: they pulled up before an old semi-collapsed building, rummaged in a skewed cabinet for lights, sledded down a ramp where once a short staircase had been, and there they were in a tunnel as high as Jack's head and an arm's length wide. Their lights were called kienspans: splits of dry resinous wood about the dimensions of a rapier blade, dipped in some kind of wax or pitch, which burnt enthusiastically, and looked like the flame-swords wielded by Biblical standouts. By this means, they could see that the mine-tunnel was lined with logs and timbers: a hefty post-and-beam lintel every couple of yards, and many horizontal logs, as thick as a person's thigh, laid parallel down the tunnel so as to join each post-and-lintel with the ones before and after it. In this way a long tubular wooden cage was formed, not to keep them in (though it did) but to protect them from a stalled avalanche of loose rubble pressing in from all sides.