Start of main content

Morse's visions of submarine telegraphy

In September 1854 Samuel Morse wrote enthusiastically to Michael Faraday about 'the great and important project of uniting Europe and America by a Submarine Telegraph, a project which has occupied my mind with much interest since the year 1842'. In 1842, this was a remarkable vision.

Electric telegraph communications had only just become viable over short distances on land. Cooke and Wheatstone developed their first telegraph in 1837 and in 1842 they laid a commercial telegraph line between Slough and Paddington Station, London, a distance of 19 miles. Two years later Morse laid his successful telegraph line between Washington and Baltimore, a distance of 50 miles.

However, communication over great distances underwater was well beyond the available technology. During the intervening years, a series of innovations gradually made Morse's vision possible. The most important of these was the discovery of gutta-percha, a water-resistant insulating material which could be extruded around the core of the cable.

Samuel Morse

Samuel Morse

In 1851 the first successful cross-channel cable was laid and by 1854 an American entrepreneur, Cyrus W. Field, was seeking financial backing for a transatlantic cable. Morse was appointed electrician to Field's company and the purpose of his letter was to share his enthusiasm with Faraday, who he thought was electrician to a British-based company with the same objective.  

Faraday, however, although he took a keen interest in underwater cable experiments performed at Lothbury Wharf, never became part of a cable venture. Morse described his submarine telegraph laid in New York Harbour, from Governor's Island to the Battery, a distance of about a mile. He commented ruefully that 'Although this line was destroyed in the midst of my experiments by being accidentally drawn up by the anchor of a vessel and cut off, it was not until I had passed communication through from station to station.' He had proved to his satisfaction that underwater communication was possible. 

It took Field several years to summon the financial backing from American and British sources before a transatlantic cable was laid.  The first cable of 1857 failed, but a second voyage in 1858 laid a cable which worked after a fashion for a little over a month. The project languished until a British commission reported on possible reasons for the failure and the U.S. Civil War drew to a close.  

In 1865 a new attempt was made, with the world's largest ship, Brunel's Great Eastern, carrying the cable, but the cable snapped and the attempt was abandoned until the following year. Again the Great Eastern set sail, and this second attempt was successful. On 27 July 1866, a successful cable spanned the Atlantic. The  Great Eastern returned to retrieve the abandoned 1865 cable, a new length was spliced on, and that line was completed to Newfoundland on 8 September. The age of instant global communication had begun.