A Measure of Pitch

The mechanical whirr of the hand drill left fine dust upon the bench. Clearing the wood grain with the side of my gauntlet, I noticed a neglected steel thread pitch gauge tucked beside an oilcan. A fan of toothed leaves bound by a central brass knurled bolt. I loosened the nut with a careful turn of my claw. Spreading the blades outward like a metallic fan, each edge revealed distinct serrated teeth. I pressed blade twenty-four against a loose hex bolt. The teeth locked flush into the spiral grooves without the slightest gap. Exact harmony. A standard preserved in hardened steel.