GoKawiilHip Hip Hooray! The opening of the first transatlantic cable was celebrated with a wide range of souvenirs, including watch fobs, earrings, pendants, charms, letter openers, candlesticks, walking-stick toppers, and tabletop displays. Photo: Division of Work & Industry/National Museum of American History/Smithsonian Institution
On 16 August 1858, Queen Victoria and U.S. president James Buchanan exchanged telegraphic pleasantries, inaugurating the first transatlantic cable connecting British North America to Ireland. It wasn’t exactly instant messaging: The queen’s 98-word greeting of goodwill took almost 16 hours to send through the 3,200-kilometer cable. Still, compared to packet steamships, which could take 10 days to cross the Atlantic, the cable promised a tremendous improvement in speed for urgent communications.
This milestone in telegraphy had been a long time coming. Samuel Morse first suggested linking the two continents in 1840, and various attempts were made over the ensuing years. Progress on the project took off in the mid-1850s, when U.S. entrepreneur Cyrus W. Field began investing heavily in telegraphy.
Field had made his fortune in the paper industry by the age of 34. The first telegraph project he invested in was a link from St. Johns, Newfoundland, to New York City, as envisioned by Canadian engineer Frederic Newton Gisborne. The venture never secured enough funding, but Field’s enthusiasm for telegraphy was undiminished. Over the next decade, he invested his own money and rallied other inventors and investors to form several telegraph companies.
The most audacious of these was the Atlantic Telegraph Company (ATC). Field and the English engineers John Watkins Brett and Charles Tilston Bright, both specialists in submarine telegraphy, formed the company in 1856, with the goal of laying a transatlantic cable. The British and U.S. governments both agreed to subsidize the project.
Terrestrial telegraphy was by then well established, and several shorter submarine cables had been deployed in Europe and the United States. Still, the transatlantic cable’s great length posed some unique challenges, especially because transmission theory and cable design were still very much under debate.
Morse and British physicist Michael Faraday believed that the conducting wire of a submarine cable should be as narrow as possible, to limit retardation of the signal. And the wider the wire, the more electricity would be needed to charge it. Edward Orange Wildman Whitehouse, an electrician for the Atlantic Telegraph Company, subscribed to this view.
The other school of thought was represented by William Thomson (later Lord Kelvin). He argued that the amount of retardation was inversely proportional to the square of the cable’s length. Thomson suggested using a large-diameter core made with the purest copper available in order to reduce the resistance. Bright, the project’s chief engineer, shared Thomson’s view. This design was significantly heavier and more costly than the one proposed by the Morse-Faraday school, and the ATC did not adopt it.
The Gutta Percha Co. manufactured the cable’s core and insulation. The core consisted of seven strands of copper wire twisted together to make a wire 0.083 inch in diameter. The finished core weighed 107 pounds per nautical mile, which was significantly lighter than the 392 pounds per nautical mile that Thomson and Bright had proposed. The copper core was wrapped in three layers of gutta-percha, a latex that comes from trees of the same name. The insulated core was then covered in tarred hemp and wrapped with iron wire. The finished cable was about five-eighths of an inch in diameter.
This Mortal Coil: Cable on the HMS Agamemnon was used to lay the first transatlantic telegraph line, which began operating in 1858. Photo: Hulton Archive/Getty Images
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