overall: 3 in x 2 in x 6 3/4 in; 7.62 cm x 5.08 cm x 17.145 cm
United States: New Jersey, Morristown
United States: Maryland, Baltimore
United States: District of Columbia, Washington
Computers & Business Machines
Engineering, Building, and Architecture
Government, Politics, and Reform
Industry & Manufacturing
National Treasures exhibit
Artifact Walls exhibit
Kendrick, Kathleen M. and Peter C. Liebhold. Smithsonian Treasures of American History
Treasures of American History online exhibition
National Museum of American History
from Western Union Telegraph Co.
Alfred Vail made this key, believed to be from the first Baltimore-Washington telegraph line, as an improvement on Samuel Morse's original transmitter. Vail helped Morse develop a practical system for sending and receiving coded electrical signals over a wire, which was successfully demonstrated in 1844.
Morse's telegraph marked the arrival of instant long-distance communication in America. The revolutionary technology excited the public imagination, inspiring predictions that the telegraph would bring about economic prosperity, national unity, and even world peace.