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 harp popular in the 18th century. Pockrich's contemporary, Ford, published "Instructions for the Playing of the Musical Glasses" while Bartl published a German version. In 1929 Bruno Hoffmann invented a glass harp consisting, "of 46 individually tuned glasses fixed on a resonant table." On March 9, 1938, Bruno Hoffmann performed on the glass harp at the London Museum in a program including Mozart's Adagio (K. 356) and Quintet for harmonica, flute, viola, oboe, and cello (K. 617), accompanied by Geoffrey Gilbert, Leon Goossens, Frederick Riddle, and James Whitehead. It was an "exquisite performance, in which the flute and viola in their