TRANSCONTINENTAL TELEGRAPH

by Dick Reiman, Historian

The Transcontinental Telegraph has been named a national Electrical Engineering Milestone by IEEE. Built in 1861 by the Western Union Telegraph Company, the line extends from Omaha, Nebraska to Carson City, Nevada, and then connects to local networks. This was the first high speed link between the Atlantic and Pacific coasts. The original line was operated until May 1869 when the transcontinental railroad was completed and the telegraph lines were then moved to follow its route.

During the mid-1800's, the application of electricity first meant telegraphy. It is easy to forget what a wonderful thing it meant to have instantaneous communications between distant points into a society were this was unknown. The time it took to send a message was previously dependent on the speed of horses and sailing ships. For example, a message by ship from New York to San Francisco took forty-five days. The overland stagecoach took twenty-three days from St. Louis to San Francisco and the Pony Express took eleven days from St. Joseph, Missouri to Sacramento, California.

Samuel F. B. Morse, the telegraph's inventor, learned from a colleague to lengthen the transmission path from a few feet to miles by increasing the number of turns on the electromagnet of the telegraph. He could not wait for the government to develop a system, but utilized private entrepreneurs to build and expand the network. The first line from Washington to Baltimore was operational in 1844, and by 1850, the telegraph expanded from Boston to New Orleans and as far west as Chicago. This set the stage for the leap to cross the continent.

On September 20, 1860, Hiram Sibley, president of Western Union, contracted for $40,000 to build the continental link, and split the venture into a western operation under four California companies, and an eastern one set up by Western Union. Building began in both directions from Salt Lake City. The Pony Express was contracted to supply the missing links as the operation proceeded. The wire used was to be galvanized iron "of the best quality." Insulators were an iron holder embedded in glass which in turn were enclosed in wooded forms. Poles were to be found "enroute" on a treeless plain. Western end materials were shipped around the Cape Horn to San Francisco. A wet cell provided 50 volts of power over a distance of 800 km (497 miles), which was unusually long because of low leakage due to low humidity.

Success came in October, 1861. On October 24, Stephen J. Field, Chief Justice of California and brother of Atlantic cable promoter Cyrus Field, sent a cable to Abraham Lincoln stating that this line "will be the means of strengthening the attachment which binds both the East and the West to the Union." With the arrival of the new technology, the Pony Express discontinued service.