glass harmonica

1900 illustration of a glass harmonica Spinning glass disks (bowls) on a common shaft are arranged with the lower notes (larger disks) to the left and higher notes (smaller disks) to the right.

The glass harmonica, also known as the glass armonica, glass harmonium, bowl organ, hydrocrystalophone, or simply the armonica or harmonica is a type of musical instrument that uses a series of glass bowls or goblets graduated in size to produce musical tones by means of friction (instruments of this type are known as friction idiophones). It was invented in 1761 by Benjamin Franklin and produces sound similar to the glockenspiel.