Edison telephone peg switchboard with six pegs, made by the Edison Telegraph Company of London Limited, London, England, 1879.

This is an early example of a telephone switchboard. Each board was designed to accommodate 24 subscribers' lines, and required an operator to make the connections between two telephone lines. The switch itself consisted of a set of horizontal bars and a set of vertical bars, insulted from each other. Each telephone line was connected to one of the vertical bars. The operator's telephone was connected at the end of the bar. Pegs were inserted into the crossing points to allow two telephones to be connected.