Ernst Chladni at the understanding of electron orbitals. Since at least 1738, a musical instrument called a "Glasspiel" or "verrillon", created by filling beer glasses with varying amounts of water, was popular in Europe. The beer glasses were struck by wooden mallets shaped like spoons to produce "church and other solemn music". Benjamin Franklin was sufficiently impressed by a verrillon performance on a visit to London in 1757 that he created his own instrument, the glass armonica, in 1762. Franklin's armonica inspired several other instruments, including two created by Chladni. In 1791, Chladni invented the musical instrument called the "euphon" (not to
Glass harmonica darker, heavier sound, that extends down into the subsonic range. The technique for playing the hydraulophone is similar to that used for playing the armonica. Glass harmonica The glass harmonica, also known as the glass armonica, glass harmonium, bowl organ, hydrocrystalophone, or simply the armonica or harmonica (derived from , "harmonia", the Greek word for harmony), 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). The name "glass harmonica" (also "glass armonica", "glassharmonica"; "harmonica