Crossed wires

By Tom Standage

In September 2017, Facebook and Microsoft announced that they had laid a new cable across the Atlantic. A touch thicker than a garden hose, it can carry 160 terabits of data per second. That’s enough to stream 71m high-definition films at once. News of its completion barely caused a ripple: free, fast global communication is part of modern life. But it was a very different story in 1858, when the first Atlantic cable was completed – an event that caused a sensation.

In the 1850s electric-telegraph networks were spreading quickly across Europe and America. But establishing undersea connections proved a challenge. The first telegraph line between England and France, spooled out of the back of a tug in 1850, only lasted a day: the wire fell victim to a French fisherman. A more substantial cable, laid in 1851, fared better, and the first direct message was sent from London to Paris in 1852. But laying cables across the Atlantic was a challenge of an entirely different magnitude. The person who did so would have to be very daring – and very rich. Cyrus Field, an American who made a fortune in the paper trade and retired at 33, was both.

Field raised money from investors and won the endorsement of Samuel Morse, the father of electric telegraphy. A 2,500-mile cable was taken to sea in June 1858. It was divided in two, with each half borne on a different ship, because no vessel could carry the whole thing. The two ships sailed to the middle of the Atlantic, spliced the ends of their cables together and then set out in opposite directions. The cable snapped three times and one of the ships had a close encounter with a whale (pictured). Eventually, on the fourth attempt, the cable settled on the floor of the Atlantic.

Queen Victoria and President James Buchanan exchanged triumphant telegrams. There were hundred-gun salutes in New York and Boston. “Our whole country”, declared Scientific American, “has been electrified by the successful laying of the Atlantic Telegraph.” Tiffany, the New York jeweller, bought the remainder of the cable and sold pieces of it as souvenirs. It was widely predicted that wiring the world with undersea cables would lead to world peace. “It is impossible that old prejudices and hostilities should longer exist, while such an instrument has been created for the exchange of thought between all the nations of the earth,” declared one of the many celebratory books. “This sea-nymph, rising out of the waves, was born to be the herald of peace,” trumpeted another.

But the triumph was short-lived. The cable was so unreliable that it took 16 hours to transmit the brief telegrams between Queen Victoria and Buchanan. The opening of the cable to commercial traffic was repeatedly delayed. After a month, the cable failed completely. Some people suggested that the whole thing had been a hoax. In fact, the electrical properties of undersea cables were poorly understood. The project’s chief engineer had wrongly assumed that the best way to send messages over long distances was to increase the voltage – but this gradually destroyed the cable.

A public inquiry followed. The star witness was William Thomson, a physicist better known today as Lord Kelvin. He figured out the relevant electrical theory and teamed up with Field to build a new Atlantic cable, which went to sea in June 1865. By the end of 1866 there were two working Atlantic cables, which were so profitable that Field paid off all his debts within a year. Laying subsea cables became commonplace. News could cross the oceans in minutes.

What does this tell us today? The tale of the Atlantic cable suggests that we should be wary of suggestions that communications technology will reduce international conflict. Even before the devastating wars of the 20th century, telegraphy was used to co-ordinate troop movements as early as 1866, in the Austro-Prussian war. Today war is waged on the internet by propaganda bots and state-sponsored cyber-attacks. But the biggest lesson is that the real communications revolution happened more than 150 years ago. We may think we live in an era of unprecedented technological change, but the advent of telegraphy was arguably a much bigger and more dramatic shift. We merely have got used to steady improvements in communications technology – our great-great-grandparents had to get used to its invention in the first place.

IMAGE: ALAMY