First transcontinental telegraph

The first transcontinental telegraph (completed in 1861) was a line that connected an existing network in the eastern United States to a small network in California by a link between Omaha and Carson City via Salt Lake City. It was a milestone in electrical engineering and in the formation of the United States of America. It served as the only method of near-instantaneous communication between the east and west coasts during the 1860s. In 1841, it had taken 110 days for the news of the death of President William Henry Harrison to reach Los Angeles.

After the development of efficient telegraph systems in the 1830s, their use saw almost explosive growth in the 1840s. Samuel Morse's first experimental line between Washington, D.C. and Baltimore - the Baltimore-Washington telegraph line - was demonstrated on May 24, 1844. By 1850 there were lines covering most of the eastern states, and a separate network of lines was soon constructed in the booming economy of California.

California was admitted to the United States in 1850, the first state on the Pacific coast. Major efforts ensued to integrate California with the other states, including sea and overland mail and passenger service. Proposals for the subsidy of a telegraph line to California were made in Congress throughout the 1850s, and in 1860 the U.S. Post Office was authorized to spend $40,000 per year to build and maintain an overland line. The year before, the California State Legislature had authorized a similar subsidy of $6,000 per year.

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