The rape-seed oil in the copper tank on the hundred-foot balcony smelled of crushed cabbage seeds and hot animal fat.
Apprentice Olla knelt beside the tank, her wool skirt tucked between her knees. He held an eight-inch brass fine-scale measuring tongs whose finely engraved jaw rested across the tank’s machined rim. The surface of the oil was dark, thick, sticky, and glassy, lit up by two shaded bullseye lanterns that cast clean circles of yellow light across the measuring grid.
In the center of the tank, suspended in the liquid like a sleeping fish, hung the eighty-pound gunmetal plummet.
Its cobalt steel tip hovered three-sixteenths of an inch above an engraved silver datum plate underwater at the bottom of the oil. The four said clearlybrass vanes had swelled horizontally, cutting through the oil to kill every trace of high-sky swinging weight swing. The wire rose straight out of the liquid, motionless, a hair-thin line of Swedish spring steel extending three hundred upright feet into the belfry above.
“Datum pin sighted,” Olla called up through her speaking trumpet. Her voice carried over the dull, steady rumble of the river. “The wire is dead calm, Master Reed! Zero shaking on the fine-scale jaw!”
