At the base of the dark rock cliff that separated the deep gap from the High Anvil, the ancient engineers had built the main smelting channel: Entry hall 718, the Geothermal Trough. Here, the floor was composed of massive blocks of heat-proof soapstone six feet thick, carved with a central curved gutter three spans wide that sloped gently toward the forge shop floor.
Overhead, anchored into the solid dark rock wall with four-inch bronze bolts, sat the main magma water gate. The gate was a slab of white soapstone wrapped in an iron frame, operated by a ten-foot lever arm of counterweighted forged iron that projected over the walkway like the boom of a cargo crane.
Qiao Ming approached the lever with bare, silent feet. The air here was hot and dry, streaming a fierce, baking warmth that caused the linseed oil in his coat to emit a rich, amber fragrance. He set down his tools upon an andesite shelf, his slate-grey eyes inspecting the bronze toggle-pins that locked the lever in its closed position.
Behind him, Yan Zhiqiu carried the sealed zirconium crucible using a pair of five-foot iron charging tongs. She stood at a safe distance on the upper narrow high walkway, her face shielded by a wet linen cloth, watching Qiao Ming’s movements with intense, focused attention.
