Down on Level Five of the Quarry, two hundred and eighty feet below the limestone rim, the cold was not a draft. It was a permanent, weeping saturation of the bedrock.
The chamber formed the main heat-absorption sink of the country restoration plan. A huge underground vault excavated sixty feet into living granite, walled with massive timber lagging and braced by twelve-inch iron support posts. For three ages, this floor had collected the drainage water of the entire western mountain basin, channeling sixty thousand gallons an hour through deep floor-trenches into the drain pits of the three Cornish pumps. For the central discharge, however, the floor had been transformed into a heat-powered crucible. Cleared of loose debris down to the bed of crushed quartzite shale, leveled with land-mapper’s instruments. Then it spanned by the sixteen linked steel bays where Melli Dorn’s heat-proof glass panels were to be seated.
Directly overhead, suspended from heavy forged-iron ceiling brackets bolted into the dark rock ceiling, ran the main cooling channel. A four-foot-width water chute built of riveted sheet copper lined with two inches of cast lead. Through that pipe rushed eight hundred gallons a minute of freezing mountain water, brought down under six bar of working head from the high pool dam to flood the water jacket beneath the glass floor. The lead lining had been cast thick to cushion the metal against high-pressure shocks, absorb the sound thunder of forty thousand tons of moving liquid, and insulate the copper against the acidic…
