Franklin's Glass Armonica

Photo of glass armonica

In the mid-1700s, Benjamin Franklin served as a delegate for colonial America and spent a great deal of time traveling to London and Paris. During this period, it was quite popular and entertaining for amateur musicians to perform on sets of "singing" or musical glasses. Franklin attended one of these concerts and was intrigued by the beauty of the sound. Almost immediately, he set to work applying the principles of wet fingers on glass to his own musical creation.

Ben Franklin completed his glass armonica in 1761. (Its name is derived from the Italian word for harmony.) He didn't simply refine the idea of musical glasses, which were played much like children at the dinner table play them today, with notes being determined by the amount of water in the glass. Rather, Franklin made chords and lively melodies possible on his new instrumental invention.

Working with a glassblower in London, Franklin made a few dozen glass bowls, tuned to notes by their varying size and fitted one inside the next with cork. Each bowl was made with the correct size and thickness to give the desired pitch without being filled with any water. Franklin also painted them so that each bowl was color-coded to a different note. A hole was put through the center of the glass bowls, and an iron rod ran through the holes. The rod was attached to a wheel, which was turned by a foot pedal. Moistened fingers touched to the edge of the spinning glasses produced the musical sounds.

"Of all my inventions, the glass armonica has given me the greatest personal satisfaction." ~ Ben Franklin