The underground roar inside the lower vault of the eastern bridge pillar didn’t shrink. It grew deeper, shaking through the soles of Tomas Reed’s boots like the purr of a sleeping beast trapped beneath fifty feet of solid granite.
Tomas knelt beside the circular iron plate in the floor. The metal was four feet in width, an inch thick. Its surface pitted with was dark patches of iron-oxide rust. Encircling the rim were twelve heavy bronze studs, each two inches square, threaded into forged iron anchors set deep into the surrounding dressed cut stone. In the center of the plate, cast in high relief beneath decades of lime slow leak, sat a stone carving:
CROWN WATER BOARD · SIPHON RELIEF NO. 1 DRAINAGE AND FLUSHING Pipe · 400 MINERS’ INCHES SEALED UNDER ROYAL Court trial · YEAR 000
“Look at the lead caulking,” Tomas said, tracing the joint between the iron plate and the stone floor with the tip of his scraper.
The caulking was not the dull, gray, rusted lead of an ancient installation. Along the northern semicircle, the lead had been recently pared back with a sharp draw-knife. That left bright, silvery shavings scattered across the damp flat stone slabs. Embedded in the fresh lead was a newly forged iron bracket, securing a heavy bypass valve with a brass rising-stem.
