In the underground vault forty feet beneath the border transit hall, Bram Ash heard the three distant horn blasts echo through the upright air-flow pipes like the call of a brass hunting trumpet across cold water.
“That’s Geth Marr,” Bram whispered. His left hand gripped the handle of the twelve-pound sledgehammer resting against his thigh. “The quarry sink has absorbed the first surge. The pressure plateau has established itself in the chimney pipes.”
Beside him, Clerk Corin Petch stood by the zinc-sheathed delegate console, his ink-stained fingers resting on the open pages of the country revocation register. The clerk had three lanterns burning now. He cast overlapping circles of yellow light across the massive stone iron cube of the Gate anchor housing.
“The high-pressure balance is at zero differential, Bram,” Corin said. His glasses reflected the dark copper ground-sheets. “If you’re going to strike the shear-pins, do it now. The heat surge from the central steam cooler will reach this lower pipe hub in less than four minutes. If the heat expands the brass sleeves, the pins will bind in their housings and no hammer in the province will knock them loose.”
Before taking up the sledgehammer, Bram had leaned over the console with a check torch, checking the posture of the bronze pins within their machined steel sleeves.
