Ben Franklin invented many items in many different categories (science, home, music, furniture, etc.). One such item was the glass armonica. It was a series of differently sized glass bowls mounted on an iron spindle. The spindle was moved by foot movements on a treadle (like how sewing machines used to be foot-powered). Water moistened fingers would be held on the rims of the spinning bowls, making a sound. The bowls each played a different tone, and so they could be “played” into a musical pattern. The image below shows a modern armonica made based on Ben Franklin’s design.