With the main cooling water chute fully sealed and the eighty thousand gallons of mountain runoff safely contained within its lead-copper casing, the three giant Cornish sump pumps finally began to win their battle against the drowned floor of Level Five.
Up on Level Three, the steam engineers threw open the main throttle valves, admitting twelve bar of dry boiler steam into the thirty-inch drive cylinders. The massive twenty-foot cast-iron walking beams, cleared of shale mud and splintered fir planks by the stonecutter teams, sped up into their full, rhythmic running rhythm: CHUG-THUMP. CHUG-THUMP.
Each stroke of the thirty-inch brass cylinders swallowed two thousand gallons of black, silt-choked water from the floor drain pits. It threw the liquid through upright discharge channels to the surface marsh four hundred feet above. The shaking of the giant engines traveled through the limestone bedrock, a deep, reassuring clockwork thrum that dispelled the choking dread of the flood. Pump mechanic Venn patrolled the pump alcoves with an iron oil-can and a long-handled rake, continuously clearing the intake strainers of floating fir bark, wet cordage, and leftover sawdust before the debris could choke the suction valves.
Within forty minutes of nonstop, thunderous pumping, the water level across Level Five dropped with astonishing speed—from waist-deep to knee-deep, then from ankle-deep down to a shallow, glistening sheen of receding puddles.
