The Experiment that Started the Experiment

Holding a piece of scrap-paper in one hand, the ball resting on a table, and snapping a picture I suddenly become interested in spherical lenses. I remember that some of the earliest microscopes (from the 1600's, I think) were made with polished balls of glass.

I decide not to look anything up on the internet until after I try building a camera using this ball as a lens.