The timber drift was three feet wide, four feet high, and smelled of damp earth, bruised spruce needles, and the hot sweat of four men working in a crawl space.
Tomas Reed knelt on his knees in the mud at the face of the drift, twenty feet beneath the collapsed arch of Bastion-Nine. The lantern hanging from the third timber frame cast a flickering, amber light over the spruce lagging boards that held back twenty tons of loose river gravel above their heads. Ahead of them, only five feet of gravel separated their tunnel from the dry void of the inner command vault.
Beside Tomas, old Peter the miner was driving an iron crowbar into the packed gravel, prising out river cobbles the size of loaves. Every stone came away with a dry, rustling hiss that made the hair on the back of Tomas’s neck prickle. The air was thin, smelling of stone dust and the bitter grease of their animal fat lamps.
“The ground is moving,” Peter whispered, freezing with his crowbar wedged beneath a flat limestone slab.
A sharp, rifle-crack sound split the gloom.
Above their heads, the main oak header-beam—a six-inch heart-timber supporting the central arch springer—splintered along its grain. A trickle of fine, dry sand began to pour through the gap between the lagging boards. It fell like an hourglass onto Tomas’s shoulders.
