The Hypostyle of the Salt Stone beams in Entry hall 906 was a vast, underground forest of squared limestone pillars, seventy arm-lengths tall and ten arm-lengths thick, supporting a ceiling of massive cut stone beams that had spanned the roadway since the Third Epoch. The air here was warm and thick with the smell of wet lime, crushed white chalk-stone, and the bitter aroma of drying cedar bark. Every column was carved with shallow, sharp-angled channels running from capital to base. Channels designed by the ancient master builders to carry away water drops during the spring thaws, but now weeping thick, milky salt water that pooled around the stone bases in slippery white crusts. High overhead. There, the shadows gathered in the deep recesses between the beams, a nonstop, faint sound rang through the gloom—a dry, rhythmic clicking, like the jaws of thousands of invisible beetles chewing through the heart of the stone.
Qiao Ming stood on the land-mapper’s staging platform, forty feet above the crowded floor of the nave. His bare feet gripped the rough pine planks of the scaffold, his toes curled over the front edge as he looked straight up into the junction of the central cross-stone beam. In his left hand he held an iron plumb, suspended on a three-fathom cord of boiled sea-silk. At the same time, his right thumb pressed the cold bronze sighting vane of his Folded brass star-compass against the dressed face of the keystone. The instrument was heavy in his grip…
