The round hall of Entry hall 340 opened before them like the hollow shell of a stone-hard nautilus.
It was sixty deep-water lengths in width, paved with circular rings of blue-black dark rock that radiated outward from a central drain thirty paces wide. Around the outer rim of the hall, climbing in a grand spiral ramp seventy arm-lengths toward the domed ceiling, stood eighty huge statues of the Moon-Scribes. Carved from pale grey pale limestone during the Second Flooding, each scribe held an open tablet of dark slate upon which the waxing and waning of pre-flood sky bodies were engraved in tiny gold characters. For two hundred years, Qiao Ming had paced those rings, measuring the sound deep ring that tied the lunar calendars to the underground tides.
Qiao Ming crossed the threshold from the access hall. Then, the sound stonework of the round hall caught the hiss of his steaming bone ladle and amplified it into a swirling, whispering vortex that circled the walls like a rising tide.
He couldn’t run straight across the room.
To draw a direct line across a circular floor would introduce an abrupt aimed shear at the exit portal. An angular hidden gap that would concentrate the water-pressure blast wave of the incoming spring tide against the thirty-fourth gate. The ancient formula carved upon the White Jade Barrier was uncompromising. The line must follow the logarithmic spiral of the nautilus, wrapping through three complete nested revolutions across the floor before reaching the southern archway.
