Ivara Quill unrolled a fresh sheet of heavy drafting linen across the butcher’s table, pinning the four corners with iron lead-weights salvaged from an old kitchen balance.
“Doma has defined the working limit,” Ivara said, her single hand dipping an iron ruling pen into a pot of black nut-dark oak-ink. Her lines were straight, ruled against an edge of polished brass with clockwork certainty. “We can’t rely on human improvisation against an enemy that processes sound data through Signal Recognition.”
She sketched a clean cross-section of the drainage water chute that ran beneath the railway interchange. A two-hundred-yard vaulted channel carved from dark rock blocks, connecting the lower boiler rooms of Tram Ward directly to the bitter salt settling drain pits of the Salt Works.
“Here is the geography,” Ivara explained, pointing the steel nib at the central span. “The water chute is six feet wide, with a high arched ceiling and a central floor trough carrying three feet of scalding drainage water from the locomotive wash-pits. Midway along the tunnel, directly beneath the coal siding on Fourth Street, sits the old settled mud check cage. It’s an enclosed iron enclosure suspended from overhead ceiling beams, built with two-inch heavy wire mesh and an upstream water gate.”
