The roar of the tidal water-mill inside Entry hall 318 swallowed every other sound in the lower vaults.
Here, forty arm-lengths beneath the level of the outer galleries, the natural drainage of four sunken districts came together into a single underground water gate-race fifty paces wide. The rushing black salt water, driven by the falling head of the half-ebb tide, surged through four huge mill-wheels carved from solid granite, each wheel thirty paces in width and banded with rusted through sea-bronze. For ten thousand years, those stones had turned in the dark, their rhythmic groaning shaking the bedrock with the power of a falling river.
Qiao Ming stood upon the damp oak narrow high walkway that spanned the second mill-race, his bare feet gripping the wet timber with horn-hard calluses. The air was a mist of cold spray and crushed stone dust that smelled of ancient peat, salt water, and the rich, honeyed sweetness of crushed amber.
Beside the narrow high walkway sat the bronze hoppers of the grinding mills. Into the first hopper, he had already emptied four sacks of the stone-hard pine resin. Above the stone throat, a heavy granite runner-stone four arm-lengths thick was rotating at twenty turns a minute, grinding the golden chunks of amber into a flour as fine and soft as cornmeal.
