Specimen of the new lightweight transatlantic telephone cable, manufactured by Submarine Cables Limited, Greenwich, London, England, 1961.

This is a specimen of the cable that was used to create the first link in the Commonwealth Round the World Cable, called the Canadian Trans-Atlantic Telephone Cable, or CANTAT-1. The cable was laid from Oban, Scotland, to Corner Brook, Newfoundland, and was completed in 1961. The cable was designed by the Post Office in 1951, and dispensed with armouring, instead giving it the strength needed for laying and recovery by incorporating a steel cable at the centre of the inner conductor. It was known as the lightweight cable because its weight in water was only one-fifth of that of a comparable armoured cable. Ninety two-way rigid repeaters, also of British design, were spaced along the route length.