In 1762, Benjamin Franklin improved the process of making music by rubbing the moistened rims of glasses. He attached perfectly tuned glass bowls on a horizontal spindle, which was set in motion by the foot. This arrangement allowed a player to produce several tones at one time. The instrument, known as the glass harmonica, attracted the interest of several composers, including Wolfgang Amadeus Mozart and Richard Strauss. The tones, which resembled those produced by the violin and the flute, sounded almost celestial, and they were thought to make a considerable impact on those who heard them. After hearing a performance on the harmonica by the famous, blind Marianna Kirchgessner in Stuttgart in 1808, the composer J. R. Zumsteg died from a "vehement attack of cramp [sic] in the chest."* Shortly thereafter, Kirchgessner herself contracted a fever from which she did not recover. The Austrian physician Franz Anton Mesmer apparently played the instrument for his patients in Vienna. Concerns about the glass harmonica arose not only from listening to it, but also from playing it. From the late 1870s on, it was believed that the vibrations produced by rubbing the glasses could cause serious nerve damage. C. F. Pohl, grandfather of the probable maker of the instrument in the Corning collection, reported that playing the harmonica "was forbidden in several countries by the police."* The making of a glass harmonica was a very demanding task. The glass bowls had to be blown and cut to the right size and pitch, and they had to fit inside one another on the spindle. Benjamin Franklin himself probably supervised the production of only two such instruments. The most famous harmonica manufacturers were members of the Pohl family in Kreibitz (Chribská), Bohemia, who continued to produce the instruments from 1785 to 1945. * Charles Ferdinand Pohl, "Cursory Notices on the Origin and History of the Glass Harmonica," International Exhibition of 1862, London: Petter and Galpin, 1862.