In May of 1761, Benjamin Franklin was in Cambridge, England, and he heard a man play a performance on musical glasses. They were crystal wine glasses filled with different levels of water, and when the performer rubbed the edges of the glasses, they produced different notes. Franklin was entranced by the sound, and he invented a mechanical version of the musical glasses that he called the glass armonica – that’s harmonica without the H. Franklin’s instrument consisted of a set of glass bowls