At four o’clock in the morning, after the courtyard filter box had been pulling continuously for two full cycles of the two-hundred-pound gravity weight, Pella Rook and Imran Bell dropped the stone steps into the sub-basement of the Ferry Museum. This time, they didn’t step down into a blinding, choking fog of boiling sulfuric vapor. The air in the stairwell was clear, cool, and crisp. It smelled faintly of damp white cedar, wet stonework, and slaked pipe lime.
Imran walked ahead, his hand-cranked dynamo torch humming with a low, spinning clockwork whine as he squeezed the spring grip at steady three-second intervals. The packed yellow beam cut straight across the forty-foot vaulted chamber, lighting up the massive dressed-granite foundation piers of the museum and the arched stonework backing of the Sluice Crown without a trace of the greasy, acidic haze that had driven them back three days earlier.
Along the brick groin-vault of the ceiling, three six-inch flexible canvas ducts—double-stitched by Mistress Hesta’s laundresses and coated with boiled linseed oil—were suspended from iron eyes driven into the mortar joints. Two of the ducts acted as fresh-air make-up lines, drawing cold, clean night air down from the Ferry Market alleyways and discharging it along the eastern floor flags. Meanwhile, the main suction trunk at the western archway pulled the warm boundary layer straight out to Eren’s cedar scrubber in the courtyard.
