(historical) An early device for recording sound by local magnetization of a steel wire, disk, or ribbon, moved against the pole of a magnet connected electrically with a telephone receiver or similar.

plural of telegraphone

plural of telegrapheme

(dated) telegram

plural of telegraphoscope

(historical) An instrument for telegraphically transmitting a picture and reproducing its image as a positive or negative. The transmitter includes a camera obscura and a row of minute selenium cells. The receiver includes an oscillograph, relay, equilibrator, and an induction coil whose sparks perforate a paper with tiny holes that form the image.