Object Details
- Morse, Samuel Finley Breese
- Description
- This is the prototype Morse telegraph transmitter made by Samuel F. B. Morse and exhibited in New York in 1837. Called a Port Rule,Morse and assistant Alfred Vail set lead slugs representing letters in the carriage that was then cranked under a rocker arm. The arm made and broke contact with two cups at one end that contained mercury thus opening and closing the circuit. The current activated an electromagnet on the receiver.
- Samuel F. B. Morse and assistant Alfred Vail constructed this telegraph transmitter in 1837 to prove messages could be sent with electricity. Morse and Vail called this device a Port Rule. They set lead slugs that represented letters and numbers in the carriage cranked under a rocker arm. The arm moved up and down dipping a wire on the end into two cups filled with mercury. That action opened and closed the circuit and sent an electrical pulse from a battery to an electromagnet mounted on the receiver.
- Credit Line
- from Western Union Telegraph Co.
- 1837
- ID Number
- EM.181250.02
- catalog number
- 181250.02
- accession number
- 31286
- Object Name
- Telegraph Instrument
- telegraph transmitter
- Measurements
- overall: 7 1/2 in x 7 in x 36 3/4 in; 19.05 cm x 17.78 cm x 93.345 cm
- See more items in
- Work and Industry: Electricity
- Communications
- Exhibition
- Inventing In America
- Exhibition Location
- National Museum of American History
- National Museum of American History
- Record ID
- nmah_1192941
- GUID (Link to Original Record)
- https://n2t.net/ark:/65665/ng49ca746aa-51c2-704b-e053-15f76fa0b4fa
