Glass Armonica
The glass armonica's forerunner, the musical glasses, were brought to Europe from China and Persia and became very popular, particularly in the British Isles.
Benjamin Franklin, the famous American physician and statesman, was very impressed by the "musical glasses" and in 1761invented the glass armonica, which, technically and musically, is considerably more valuable. The instrument consists of glass bowls mounted horizontally on an axis which are set in rotating motion by a pedal.
The pressure of the finger on the moist glasses produces an indescribable beauty of pure sound.
Within a very short space of time, the glass armonica became one of the most celebrated musical instruments of the eighteenth century. Beethoven, C.P.E. Bach, Naumann, Reichardt, Röllig and others were so fascinated by this instrument that they composed solo pieces as well as chamber music works for it.
Mozart's meeting with the celebrated glass armonica virtuosa Mariane Kirchgessner in Vienna impressed him deeply and inspired him to write an Adagio and Rondo for glass armonica, flute, oboe, viola and violoncello KV 617 as well as the Solo Adagio in C minor KV 617a.
Benjamin Franklin / Glass Armonica, Germany about 1800, Berlin