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
Harmonica and the timing, and usually states the key of the harmonica required for the song. Complete example of harmonica tab: A number (sometimes inside a circle) appears below each note in otherwise conventional sheet music, and indicates which number hole to play. An up or down arrow beneath the number indicates whether to blow or draw. Up means blow and down means draw. A curved arrow indicates bend notes—slightly to the left for a half step flat, and longer to the left to indicate a whole step flat. Right-pointing arrows indicate a sharp bend. Harmonica The harmonica, also known as