At the bottom of the eight-foot vertical shaft, the air was damp, close, and sour with the metallic reek of nitric putty and wet river-silt.
Lady Signe Lorr stepped off the lowest pine rung onto the packed gravel floor at the mouth of the horizontal drift, crouching slightly so the crown of her silver hair cleared the rough-hewn pine head-trees. Directly behind her, Jon Hale dropped silently onto the earth with his heavy ash tap-mallet looped to his left wrist and his right hand holding the shuttered bull’s-eye lantern, while Alden Bram braced his massive shoulders in the shaft entrance, sliding the iron hook of his ash measuring rod until it rested two inches from the key pine wedge of the second ceiling prop.
Twelve feet ahead of them at the blind end of the drift, Senior Oath Guard Keld knelt on both steel-greaved knees before the massive, dressed-granite back face of the River Lantern’s central foundation pier.
Seen from three paces away in the dim red glow of his mining-lamp, the demolition rig Keld had seated into the ancient mortar was a terrifying piece of royal siege-craft. Three cylindrical brass fire-pots, each eight inches in diameter and stamped with the broad arrow of the Royal Arsenal, had been hammered flush into chiselled pockets between the lower granite courses—directly opposite the spot on the inner cellar floor where the iron-bronze spike of the Hearth Nail entered the bedrock. Thick collars of grey thermal putty sealed the mouths of all three…
