“If you are going to poke a man-eating debt through a keyhole,” Noll Vey said, kneeling on one carved basalt knee beside the ninth door while Tessa Dene wedged a brass plumb-bob against the lower hinge-pin, “I would vastly prefer that we poke it with a very long stick.”
“We are not poking it, Master,” Prit said briskly. The bone steward had brought his three-legged stool down to the foundation passage and set a fresh slate across his knees, with grey audit chalk in his hand and a borrowed pocket-watch of Cale’s ticking on an upturned mortar bucket. “We are conducting a differential calibration of Debt Ten’s boundary conditions. Kindly keep your stone thumb off the hinge-strap; your pulse-hum interferes with the plumb-bob.”
“I don’t have a pulse,” Noll pointed out.
“You have theatrical anxiety,” Prit replied without looking up. “In basalt, it vibrates at nearly the same pitch as a loose wagon axle. Tessa, is the wire clear of the mortar?”
Tessa leaned her cheek close to the stone jamb, breath misting in the yellow glow of the cresset. She had tied a hair-thin copper wire from the hinge-pin of the ninth door to the tip of an ash splinter resting on an empty preserve jar, forming a miner’s tremor-gauge like the ones her father Edren used to detect roof-slips in the silver drift.
