The Brass Sovereign drifted within ten deep-water lengths of the central vortex.
The surface of the flooded tiered arena had organized itself into a huge, rotating whirlpool three hundred paces across. In the center of the whirlpool, directly above the underwater Council Floor of the High Dais, a spinning funnel of dark water dropped fifteen feet below the surrounding surface. It exposed the upper rim of the Master Siphon Gate.
The gate was a massive circular disc of cast glowing-bronze, twelve arm-lengths in width and eighteen inches thick, engraved with the twelve sky-high signs of the Drowned Dao. In the pre-flood era, when the tiered arena served as the central water-court of the Seven Seas, this gate controlled the seasonal drainage of the entire mountain. It opened during the winter monsoon to flush the piled up silt into the deep-sea trenches.
The Master Siphon Gate was cast during the reign of the Third Patriarch from an alloy of seventy parts copper, twenty parts tin, and ten parts star-fallen silver. The silver was added not for decoration, but to prevent the growth of freshwater mollusks and slime-algae that might foul the seating surfaces over hundreds of years of flooding. The gate was twenty tons of solid metal, balanced by balance weights hidden within the granite piers of the High Dais. It needed only a fifty-pound clockwork impulse to trip its master release.
