1To Benjamin Franklin from Vergennes, 19 November 1781 (Franklin Papers)
...with his habitual condescension, touching the ends of his fingers on a moistened piece of sponge, and commenced playing with his right foot, bearing upon a treadel fixed in the manner of a spinning wheel, which turned a set of musical glasses, presenting their edges in perpendicular positions, in the shape of saucers graduated of different sizes, so as to produce all the requisite tones. He...