Many years ago a fellow student at my university told me a story about an experiment a class of honors students had conducted with their professor a semester or two earlier, involving a robotic drill invented by one of them with which a very deep hole was drilled in the floor in the corner of the classroom. Then, by smiling when the professor was warm and frowning when he was cold, the students eventually maneuvered the professor, who wanted to be accepted and considered pleasing and entertaining, into the hole.

After he fell in they connected the two ends of the hole and he is possibly still falling now, thirty years later. Although he must have attained terminal velocity long ago, he still continues to accelerate, very slowly, as friction from particles suspended in the air, and the air molecules themselves, polish the rough fibers of corduroy trousers and tweed jacket he was wearing that day.

It is one of the most fondly-recalled pranks in the history of the honors program at that university, and alumni amuse themselves at reunions by calculating the professor’s current velocity.