The world’s first submarine transatlantic telephone cable system was inaugurated.

Known as Transatlantic No. 1 or TAT-1, the £120 million system actually consisted of two identical cables to allow transmission in each direction. Prompted by the successful installation of a submarine cable between Florida and Cuba in 1952, a consortium of the UK’s General Post Office, the American Telephone and Telegraph Company, and the Canadian Overseas Telecommunications Corporation agreed to investigate the feasibility of a transatlantic cable.

It was already possible to make a transatlantic telephone call when the 1,950 nautical mile long cable began to be laid in 1955. However, ...