Telegraph Key

Telegraph Key

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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.
Location
Currently not on view
Object Name
telegraph key
Object Type
Patent Model
date made
1873
maker
Wessmann, Martin F.
Physical Description
wood (overall material)
brass (overall material)
gutta percha (overall material)
Measurements
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
EM.308872
catalog number
308872
accession number
89797
patent number
142826
See more items in
Work and Industry: Electricity
Telegraph Keys
Communications
Data Source
National Museum of American History
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