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 chastened and the dulcet notes of the instrument would be delightful indeed, were they more powerful and articulate; but that we believe the most perfect execution cannot make them. In a smaller room and an audience less numerous, the effect must be enchanting. Though the accompaniments were kept very much under, they were still occasionally too loud." Music for glass harmonica was all-but-unknown from 1820 until the 1930s (although Gaetano Donizetti intended for the aria "Il dolce suono" from his 1835 opera Lucia di Lammermoor to be accompanied by a glass armonica, and Richard Strauss specified use of the instrument