The access hatch for Conduit Trunk B was set into the concrete foundation slab behind the backup regenerator chambers, thirty paces from the main blast floor.
It wasn’t a decorative bronze door. It was a heavy circular manhole cover of cast iron, three feet across, three inches thick, secured by four heavy dog-clamps and stamped with raised letters crusted in yellow sulfur scale:
TRUNK B — Star tower THERMAL FEEDER — HIGH PRESSURE.
Melli Dorn knelt beside the hatch. He drove the chisel end of Bram’s five-foot iron crowbar under the pry-notch on the rim. With a grunt of brute physical effort from her broad back, she threw her weight onto the lever. The iron dog-clamps groaned, their threads squealing against decades of crystal-hardened graphite grease, before the heavy lid broke free with a sharp, ringing crack that sounded like an anvil striking stone.
She hauled the circular iron slab aside, letting it drop onto the cinders.
The blast of air that erupted from the opening was terrifying.
It didn’t billow outward as steam. It was an invisible, white-hot chimney updraft. It ran past sixty degrees at the rim, that smelled of scorching stone oil, baked asbestos cloth, and the sharp, spark ozone of raw copper current. Len felt the hair on his forearms curl in the draft. The sweat that broke across his forehead evaporated in mid-air before it could run down his temples.
