The registry vault of Entry hall 688 was a massive circular hall built from interlocked blocks of dark green-stone, banded with polished copper hoops four inches wide. Suspended around the outer edge of the room were twenty-four lit up drafting slates of ground quartz, backlit by dormant channels that had once carried eerie-glowing algae fluid.
Upon these quartz panels, etched with acid and filled with red stone lacquer, were the complete stone-built blueprints for Planetary Dynamo Alpha. The main machine designed by the engineers of the Second Epoch to generate man-made spiritual qi for forty underground cities.
Qiao Ming walked from panel to panel, his bare horn-hard feet pressing against the green-stone floor flags. The stone was cool and smooth, holding a faint, soapy texture characteristic of magnesium-rich minerals. He held his horn lantern close to Panel Four, which showed the upright cross-section of the dynamo stator.
The scale of the machine was staggering. The stator ring was one hundred and twenty arm-lengths in width, wound with forty thousand turns of nonstop, oxygen-free copper bar three inches square. Suspended within the stator was a rotor of forged star-fallen iron weighing eighteen thousand tons. It was driven by eight high-pressure steam turbines fed by the earth-heat channels of Entry hall 670.
