Telegraph Key

Description (Brief)
Telegraph keys are electrical on-off switches used to send messages in Morse code. The message travels as a series of electrical pulses through a wire. The sequence and duration of pulses represent letters and numbers. This patent model shows Martin Wessmann's design for an automatic key. His idea involved a key for each letter, number and character, somewhat like a piano keyboard. Each key included a circuit breaker controlled by gearing so that the pulses were generated at a regular speed. That prevented operators from blurring the message.
Currently not on view
Object Name
telegraph key
date made
Wessmann, Martin F.
Physical Description
wood (overall material)
brass (overall material)
gutta percha (overall material)
overall: 4 3/4 in x 3 1/4 in x 9 1/2 in; 12.065 cm x 8.255 cm x 24.13 cm
ID Number
catalog number
accession number
patent number
Telegraph Keys
See more items in
Work and Industry: Electricity
Telegraph Keys
Data Source
National Museum of American History, Kenneth E. Behring Center
Additional Media

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