Electric telegraph

The electric telegraph did not burst suddenly upon the scene but rather resulted from a scientific evolution that had been taking place since the 18th century in the field of electricity. One of the key developments was the invention of the voltaic cell in 1800 by Alessandro Volta of Italy. This made it possible to power electric devices in a more effective manner using relatively low voltages and high currents. Application of the battery to telegraphy was made possible by several further developments in the new science of electromagnetism

In 1832 Samuel F.B. Morse, a professor of painting and sculpture at the University of the City of New York (later New York University), became interested in the possibility of electric telegraphy and made sketches of ideas for such a system. In 1835 he devised a system of dots and dashes [Morse code] to represent letters and numbers. In 1837 he was granted a patent on an electromagnetic telegraph. Morse had formed a partnership with Alfred Vail, who was a clever mechanic and is credited with many contributions to the Morse system. Among them are the introduction of a simple make-and-break key, the refinement of the Morse Code so that the shortest code sequences were assigned to the most frequently occurring letters, and the improvement of the mechanical design of all the system components. (Read more)

In 1843 Morse obtained financial support from the U.S. government to build a demonstration telegraph system 60 km (35 miles) long between Washington, D.C., and Baltimore, Md. Wires were attached by glass insulators to poles alongside a railroad. The system was completed and public use initiated on May 24, 1844, with transmission of the message, “What hath God wrought!” This inaugurated the telegraph era in the United States, which was to last more than 100 years.

First telegraphic message—24 May 1844. Library of Congress, Samuel Finley Breese Morse papers, 1793-1944.
The image is in public domain

To read more and view the items on display in the Archives, see next page

One thought on “Electric telegraph

Comments are closed.