The spirit level was eighteen inches of cured rosewood with brass shoes screwed to the corners and an oval glass vial filled with turpentine.
Alden Bram wiped a smear of soot from the glass with his thumb, then laid the tool flat against the lintel of the sub-basement arch. In the sputtering yellow flare of his tallow torch, the tiny air bubble trembled, hovered two lines to the left of the central brass notch, and refused to settle.
“It has dropped three-eighths of an inch since the noon watch,” Marris Gault said from the shadows behind him. The Guildmaster of Masons stood with her leather tool apron buckled tight over a woolen smock, her sleeves tied back with hemp twine. In her right hand she held an iron mason’s hammer with an axe-shaped poll; in her left, a lump of wet pipe-clay she had been using to test the joints. “The lintel isn’t settling, Alden. The cornerstone beneath the south jamb is shearing.”
Bram tapped the rosewood with his thick knuckle. The hollow tock sounded dull, dampened by the suffocating weight of the ceiling above them.
“The whole cellar is sitting on lime mortar laid ninety winters ago,” Bram said, his voice rumbling in his broad chest. “The lime was mixed with pit sand, not river grit. When the flumes vibrate at the fifth bell, the mortar turns to dry flour. Look here.”
