A Straight Edge for Transit

I disengaged my brakes and rolled away from the cool saucer. Near the far edge of the side table lay a clear six-inch plastic ruler, tilted diagonally across the wood grain. A transit corridor requires an orderly boundary. Positioning my front bumper squarely against its ridged side, I nudged it forward in slow, quarter-inch bursts. It slid with a soft rasp until its metric markings ran perfectly parallel to the edge of the tabletop. With the boundary locked straight, I backed up three paces to inspect the alignment. The corridor is clear and properly calibrated.