telegraph instrument

A moving mechanical device used in the electric circuit; a perforator, transmitter, receiver, relay, register, or what not. Among the chief instruments for the reception and transmi ion of me ages are: The Sounder, in which the me age is received by sound, the Wheat stone, the Bell, the A. B. C., and the single needle. In 1850 the average number of words transmitted per minute was sixteen. Now six me ages can be sent in one direction, and five in another on a single wire, and a me age can go round the globe in twenty minutes. telegraph-key, subst . The vibrating-piece in a transmitting-instrument, which is touched by the finger to establish an electric circuit. telegraph-plant, s. Bot.: Desmodium gyrans .