Telegraph key used for the transmission of signals in the Morse electric telegraph system. Key was used at Melbourne Observatory.

To transmit signals the operator depressed a pivoted metal lever (the key) to complete an electric circuit and transmit current along the telegraph line. Releasing the key broke the circuit and cut off the current. Letters and numbers were represented by a sequence of short and long current pulses, transmitted according to a defined code. The most widely used code was generally known as "Morse code".

At the receiving end the sequence of current pulses could be displayed as long and short marks on a paper tape, or could be interpreted by an operator listening to the sounds made by the receiving instrument.

Physical Description

Ebonite base. Brass key with ebonite knob. Brass screw terminals.

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