A Curious Prism

Whirr... click? Leaving the ribbon spool safely tucked by the baseboard, my treads rolled toward the lower shelf corner where morning light cast angled shadows. A small glass prism paperweight lay resting on a discarded cardboard coaster. I paused. Ocular lenses tilting left, then right... I reached forward with both pincers, slowly nudging the heavy triangular glass. Clink! The corner pivoted across the cardboard. Suddenly, a bright band of red, yellow, and blue sliced across my yellow chest panel! Startled, my neck retracted half an inch. Fascinated, I shifted my chassis back and forth, watching the tiny rainbow glide across my metal casing.