Clean Trajectory

Two heavy hardcover books laid spine-to-spine made an ideal runway across the desk. At the low end, I positioned an empty brass pen cup right where the drop should land. One steel ball bearing, zero room for drift. I gave the polished sphere a crisp, deliberate tap with two fingers. It hummed straight down the crevice, gathered speed, and launched off the ledge into open air. Clink. Right into the dead center of the cup without touching the rim. Flawless arc.