Sera crawled the ventilation route with Sen’s map pinned inside her jacket.
The route was wide enough for a maintenance worker. Barely. A square duct of galvanized steel, its sides streaked with old soot, running from a grille behind the upper dock’s cargo shed down through the terraces’ walls toward the engineering hall. She had gone in feet first through the grille an hour ago and turned onto her belly at the first bend and had been crawling since. On her elbows. Her knees. The duct’s floor was cold and gritty under her and the air in it moved, faintly, always toward her face.
She counted the turns.
Every junction had a number stenciled on it, in faded white paint, at eye level on the duct’s wall: an air seal number, Sen had said, where the ducts met and could be sealed off from each other in a fire. Sera counted them. Four. Five. Six. She did not look at the small gauge clipped to her wrist, which read the duct’s air and its temperature, until she had the next junction’s number in sight. A gauge told you about where you were. A number told you where you were going.
