Ivara Quill brought the brass hammer down against the curved wall of the steam riser with three sharp, exactly spaced strikes:
Tink... Tink... Tink.
The sound was tiny in the room, but through the solid cast iron of the six-inch pipe, it rang with the piercing clarity of a struck wine glass. The metal sang at nearly twelve hundred cycles per second, a clean, high-hum sound pulse that traveled in a heartbeat upward through the floorboards, racing through forty feet of upright riser before splitting into the lateral heating branches that fed the upper platform and the passenger concourse.
Len pressed his right ear against the cold zinc of the air-powered tube. At the same time, his left hand remained clamped to his ribs, protecting his stitched arm from the shaking. Through his Road Sense, he felt the high-hum chime streaming through the foundation stonework. He traveled out through the floor beams like ripples across a dark pond.
Ivara held the brass hammer suspended two inches above the iron curve. She stood with her feet planted wide, her empty left sleeve pinned flat across her ribs. Her single hand held the hickory handle with the balanced care of an artisan.
