Entry hall 110 was not a safe hall for prayer; it was an instrument of math.
The hall was seventy paces wide, circular in plan. It was surrounded by twelve huge piers of dressed dark rock that supported a towering cone-shaped small roof-dome eighty arm-lengths above the floor. In the center of the chamber, rising out of a deep basin of dark, oily salt water, stood the Great Saline Gauge. An upright column of hollow rock-crystal four arm-lengths thick and forty arm-lengths tall, bound with massive hoops of green rust bronze.
Inside the crystal column, suspended within a column of pure spirit-liquid silver that glowed with a faint, silvery soft glow, floated twelve graduated floats carved from polished amber.
Qiao Ming stood upon the narrow watching ring of dark stone that encircled the gauge, his bare feet gripping the cold, slick stone. The air in the chamber was intensely humid, heavy with the sharp reek of packed salt water and the metal chill of cold liquid silver.
He rested his horn lantern on an iron ledge-stone and took a long, steady breath through the boiled linen cloth tied across his nose.
His eyes were fixed upon the amber floats within the crystal column.
