SS Great Eastern completes the transatlantic telegraph cable, July 1866

Background. The Atlantic Telegraph Company, formed in 1856, initially laid a cable in 1858 that failed due to insulation deterioration. By 1865, the SS Great Eastern was repurposed for cable laying. On 15 July 1865 the ship left the Nore for Foilhommerum Bay, Valentia Island, where the shore end was laid by Caroline; the deep-sea cable end was later lost mid-Atlantic. This failure necessitated a new expedition in 1866 to complete the connection.

1866 Expedition. In 1866, Field laid a new, more durable cable using the SS Great Eastern. The ship had previously taken on wire at Sheerness in May 1865. The 1866 operation succeeded where the 1865 attempt failed, establishing a permanent link. In July 1866 a third cable was laid from the Anglo-American Cable house on the Telegraph Field, Foilhommerum, on Valentia Island.

Recovery of 1865 Cable. In August 1866, several ships including the Great Eastern put to sea to grapple the lost cable from 1865. The cable was retrieved in early September 1866, taking 26 hours to bring it safely on board. This recovery allowed the splicing of the 1865 cable, resulting in two cables in service, reinforcing the permanent connection established in 1866.