
Thomas Alva Edison announced his invention of the first phonograph, a device for recording and replaying sound, on November 21, 1877 and he demonstrated the device for the first time on November 29 (he patented it on February 19, 1878; US Pat. No. 200,521). Edison's phonographs recorded on a cylinder using up-down (vertical) motion of the stylus. Edison concentrated his efforts on cylinders, since the groove on the outside of a rotating cylinder provides a constant velocity to the stylus in the groove, which Edison considered more "scientifically correct".
We estimate the value of this piece to be between $800-1200
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