Underwater connection that brought clarity to the west

IT IS a long and choppy way from Oban on the windswept west coast of Scotland to Clarenville on the east coast of Canada – 2,240 miles to be precise. But thanks to a cable stretched out two miles below the cold Atlantic Ocean, Scotland's links to North America became if not physically closer, then a lot clearer, 50 years ago this month.

The first transatlantic submarine cable went live at 6pm on 25 September 1956 – instantly trebling the number of calls that could be made between the UK and the United States or Canada and giving customers vastly improved sound quality. The cable, which replaced unreliable, crackly radio links, allowed for 36 simultaneous transatlantic conversations.

Amazingly, considering that it cost the princely sum of 3 for three minutes – today the same call would cost less than 30p – the cable carried almost 300,000 calls in its first year of service.

The cost reflected the huge investment and technological difficulties of installing the cable, in a joint initiative between the Post Office Engineering Department, the American Telegraph and Telephone Company (AT&T), Bell Telephone Laboratories and the Canadian Overseas Telecommunications Corporation. Fifty per cent of the shares were held by the American companies, 40 per cent by the Post Office Telecommunications and 10 per cent by the Canadians.

The project was extremely ambitious, with two armoured sub-sea cables developed by Bell Laboratories used to connect Oban with Clarenville. The cable was laid by the cableship Monarch – built by the Post Office in 1945 to replace a vessel of the same name destroyed during the war - and it was the only ship capable of conveying the 1,500 nautical miles of cable which had to be laid in one piece across the deepest part of the Atlantic.

The Oban end of the cable was then connected to Glasgow and London, with the Clarenville end linked to Newfoundland and on to Nova Scotia.

"The advent of the first transatlantic cable, which was nicknamed TAT1, was hailed as a major breakthrough in telecommunications and heralded the age of reliable and cost effective mass communication across the Atlantic," says David Hay, BT's head of heritage and corporate memory.

Using technologies developed during and after the Second World War, the cable cost 12.5 million to lay and took three years to complete. Hay adds: "By any standards this was a historically significant engineering achievement."

When transatlantic calls arrived, the service was opened at Lancaster House in London by the Postmaster General, who spoke to the AT&T chairman calling from New York, and to the Canadian minister of transport.

It was instantly popular with members of the public wealthy enough to use it. In the first 24 hours, there were 588 calls made between London and the US and 119 from London to Canada. In its first year of service, TAT1 carried about 220,000 calls between Britain and the US and 75,000 between Britain and Canada, raising 2 million revenue shared between the three countries."Those first callers would have noticed a massive difference in the quality of service," says Hays. "Not only was TAT1 able to sustain a far greater number of calls at any one time, and most calls could be placed within 10 minutes of a request to the operator, but radio calls were often plagued by interference and fading and people had to wait hours to be connected."

While TAT1 ceased service in 1978, it proved a starting point for future research and developments – including the much more sophisticated transatlantic projects TAT8 and TAT9 – involving the use of optical fibre cables and digital technology.

"It would have been impossible to predict 50 years ago the kind of volumes of traffic crossing the Atlantic today," adds Hay. "With the development of broadband and internet-based technologies, mass communications between Britain and North America can only be set to grow.

"None of it would have been possible without these early technological breakthroughs."

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