The bronze check grate in the center of the ground-floor flags was three feet square, cast in a heavy lattice pattern of linked open diamonds. Kezra and Yseld levered it upward with two iron pry-bars. Then, the metal hinges groaned with a dry, screeching complaint that set Kezra’s teeth on edge.
A column of cold, underground air billowed up through the opening. It smelled intensely of damp pale limestone, crushed slate, and the faint, bitter tang of copper ore.
Paxa Sel knelt right away by the rim of the square opening. She held a small animal fat candle seated in a punched holes in copper basket suspended from a thirty-pace coil of bare copper wire. She didn’t allow Kezra to lean over the shaft until the air had been tested.
“Choke-damp sits in dead drain pits like cold oil,” Paxa explained. She lowered the candle inch by inch into the blackness. “If the foundation vault has no lower drainage fissures, carbon damp accumulates over decades. You step off the ladder, take two breaths, and collapse before your friend can grip the rope.”
Kezra watched the tiny yellow flame go down into the dark. Ten paces down, the light lit up smooth cut stone blocks of grey limestone laid in regular eighteen-inch courses. At twenty paces, the shaft widened into a broad vaulted gallery. At twenty-nine paces, the copper basket touched a floor of flat bedrock flags.
