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.

Date Made: 1873

Maker: Wessmann, Martin F.

Location: Currently not on view

See more items in: Work and Industry: Electricity, Telegraph Keys, Communications


Exhibition Location:

Data Source: National Museum of American History

Id Number: EM.308872Catalog Number: 308872Accession Number: 89797Patent Number: 142826

Object Name: telegraph keyObject Type: Patent Model

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


Record Id: nmah_706722

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