It was the American inventor and painter Samuel Morse who came up with the idea of a transatlantic submarine telegraph link, just a matter of years after the publication of the telegraph code that bears his name. The completion of the first cable in 1858 led to flags in the streets of New York and the churches ringing their bells.

But it soon failed and it was eight years before a new attempt succeeded. For this there was the largest ship the world had seen, the iron-hulled Great Eastern, designed by Isambard Kingdom Brunel and built in collaboration with John Scott Russell, and capable of carrying a massive weight of cable. There was also a great improvement in cable design masterminded by the physicist William Thomson, later to become Lord Kelvin.

Dr Alan Walker of the University of Edinburgh tells the story of cables, ships and human determination.