The sound came up through the bedrock like the slow, rhythmic heartbeat of an iron whale dying in deep water.
THUD... THUD... THUD...
It shook at eighteen cycles per second, a pitch so low that the human ear registered it less as a sound tone and more as a nauseating, rhythmic pressure in the chest and temples. With every stroke of the unseen piston leagues away in the outer deep pit, the stone under Qiao Ming’s bare feet trembled. It sent tiny ripples across the dark puddles of drainage salt water that lined the gutters of Entry hall 316.
He knelt upon the ribbed banded limestone threshold, pressing the palm of his left hand flat against the cold stone. His prehensile toes dug into the joints between the slabs, feeling the micro-shakes traveling along the foundation keel of the House.
“Piston width forty arm-lengths,” Qiao Ming said, his voice quiet, measured, tuned to the rhythm of a water-mapping sounding log. “Stroke speed twelve feet per second. Double-acting back-and-forth steam drain tube. He has anchored the intake bell against the western breakwater.”
Beside him, Yan Zhiqiu leaned her back against a fluted pilaster, her scarred fingers resting upon the top edge of her broken slate. Her face was pale in the dim eerie glow of the vault moss, the dark circles beneath her eyes telling of forty hours without sleep.
