The machinery loft of the Clepsydra Tower was suspended twenty arm-lengths above the eight-sided basin, held between four massive columns of purple red stone that arched inward to support the ribbed small roof-dome.
Here, in the warm, dry air that rose through the central shaft of the tower, Qiao Ming knelt upon the bronze grating beside the fractured gear catch arbor. In his right hand he held the curved bronze pry-bar, its polished snout wedged beneath the shoulder of the broken wheel. In his left, he held an eight-ounce copper mallet wrapped in greased pigskin to prevent marking the metal.
Beside him, Yan Zhiqiu held her animal fat lantern at an angle of forty-five degrees, lighting up the ancient arbor in a pool of clear amber light. On her knees lay the clean linen handkerchief, spread out across the bronze grating to catch the locking key.
“Hold the lantern steady, record-keeper Yan,” Qiao Ming said, his voice quiet, flat, and filled with the intense concentration of a master watchmaker. “The key is half an inch wide. When the wheel moves, it will slide free.”
He tapped the pry-bar with the copper mallet.
Tink... Tink... Clack.
The fractured gear wheel—frozen on its shaft for thirty-four hundred years—yielded to the leverage. It slid smoothly along the four-inch steel arbor, its rusted bore freeing itself from the shoulder with a soft, metal sigh. As the wheel cleared the shaft, the box-shaped star-fallen iron key slipped from its keyway, dropping neatly into the center…
