Morse sounder, 1835-1910

Made:
1835-1910 in unknown place

Buy this image as a print 

Buy

License this image for commercial use at Science and Society Picture Library

License

Buy this image as a print 

Buy

License this image for commercial use at Science and Society Picture Library

License

Buy this image as a print 

Buy

License this image for commercial use at Science and Society Picture Library

License

Science Museum Group Collection
© The Board of Trustees of the Science Museum

Science Museum Group Collection
© The Board of Trustees of the Science Museum

Science Museum Group Collection
© The Board of Trustees of the Science Museum

Morse sounder, unknown maker, 1835-1910. Used by the Post Office from 1874

Morse sounder, unknown maker, 1835-1910. Used by the Post Office from 1874.

Morse code was the standard code for communicating by telegraph. The code uses a series of short and long connections in the electric current, usually called 'dots' and 'dashes'. These dots and dashes could then be decoded to reveal the message being transmitted. A telegraph sounder comprises a spring-loaded metal arm, pivoted near the middle. At one end is an electromagnet and at the other, an anvil. When a current passes, the electromagnet pulls the arm down, making a 'clunk'. When the current ceases the arm springs back against the anvil with another clunk. A dash is about three times as long as a dot, so the time interval between clunks indicates the dot or dash. The arrangement frees the operator to write down the message as it is received.

Details

Category:
Telecommunications
Object Number:
1911-17
Materials:
copper (alloy), metal (unknown), plastic (unidentified) and wood (unidentified)
Measurements:
overall: 175 mm x 175 mm x 115 mm, 1.59 kg
type:
telegraph
taxonomy:
  • component - object
credit:
Donated by H.M. Postmaster General