Object Details
- Foote, Pierson & Co.
- Description (Brief)
- Telegraph keys are electrical switches used to send coded messages that travel as a series of electrical pulses through a wire. Due to special difficulties in sending pulses through long underwater cables, so-called double-current keys were used. Instead of the short dots and long dashes of land-line telegraphs, submarine telegraphs sent positive pulses and negative pulses that made the receiver move right or left. The operator pressed one lever on the key to send a positive pulse and another to send a negative pulse. The code consisted of the sequence of left and right movements recorded on a paper tape.
- A double key for submarine telegraphy. A hard rubber base with four feet on which is mounted two telegraph keys side-by-side and four binding posts. Circuit is inlaid on bottom, wires are covered by wax. No extant maker's marks.
- Location
- Currently not on view
- Credit Line
- from Western Union International
- ca 1890
- ID Number
- EM.329942
- accession number
- 283729
- catalog number
- 329942
- Object Name
- cable key
- telegraph key
- submarine telegraph key
- Physical Description
- slate (overall material)
- brass (overall material)
- Measurements
- overall: 2 1/2 in x 4 1/2 in x 6 1/4 in; 6.35 cm x 11.43 cm x 15.875 cm
- See more items in
- Work and Industry: Electricity
- Telegraph Keys
- Communications
- National Museum of American History
- Subject
- Telegraph
- Record ID
- nmah_1193967
- GUID (Link to Original Record)
- https://n2t.net/ark:/65665/ng49ca746aa-509e-704b-e053-15f76fa0b4fa
