On August 16, the first message sent across the cable was, "Glory to God in the highest; on earth, peace and good will toward men." Then Queen Victoria sent a telegram of congratulation to President James Buchanan through the line, and expressed a hope that it would prove "an additional link between the nations whose friendship is founded on their common interest and reciprocal esteem." The President responded that, "it is a triumph more glorious, because far more useful to mankind, than was ever won by conqueror on the field of battle. May the Atlantic telegraph, under the blessing of heaven, prove to be a bond of perpetual peace and friendship between the kindred nations, and an instrument destined by Divine Providence to diffuse religion, civilization, liberty, and law throughout the world."
These messages were the signal for an outburst of enthusiasm. Next morning a grand salute of 100 guns resounded in New York City, the streets were decorated with flags, the bells of the churches rung, and at night the city was illuminated[4] . The Atlantic cable was a theme for innumerable sermons and a prodigious quantity of doggerel.
Disappointment in great ideas
However, in September, after several days of progressive deterioration of the insulation, the cable failed. The reaction at this news was tremendous. Some writers even hinted that the line was a mere hoax, and others pronounced it a stock exchange speculation.
Field was undaunted by the failure. He was eager to renew the work, but the public had lost confidence in the scheme, and his efforts to revive the company were futile. It was not until 1864 that with the assistance of Thomas Brassey and John Pender that he succeeded in raising the necessary capital. The Glass, Elliot and Gutta-Percha Companies were united to form the Telegraph Construction and Maintenance Company (Telcon, later part of BICC), which undertook to manufacture and lay the new cable. C.F. Varley replaced Whitehouse as chief electrician.
Much experience had been gained in the meantime. Long cables had been submerged in the Mediterranean and the Red Sea. With this experience an improved cable was designed. The core consisted of seven twisted strands of very pure copper weighing 300 lb per nautical mile (73 kg/km), coated with Chatterton's compound, then covered with four layers of gutta-percha, alternating with four thin layers of the compound cementing the whole, and bringing the weight of the insulator to 400 lb/nmi (98 kg/km). This core was covered with hemp saturated in a preservative solution, and on the hemp were spirally wound eighteen single wires of soft steel, each covered with fine strands of manila yarn steeped in the preservative. The weight of the new cable was 35.75 long hundredweight (4000 lb) per nautical mile (980 kg/km), or nearly twice the weight of the old.
The Great Eastern
The new cable was laid by the ship Great Eastern captained by Sir James Anderson.[5] Her immense hull was fitted with three iron tanks for the reception of 2,300 nautical miles (4260 km) of cable, and her decks furnished with the paying-out gear. At noon on July 15, 1865, the Great Eastern left the Nore for Foilhommerum Bay, Valentia Island, where the shore end was laid by the Caroline. This attempt failed on July 31 when, after 1,062 miles (1968 km) had been paid out, the cable snapped near the stern of the ship, and the end was lost.[6]
The Great Eastern steamed back to England, where Field issued another prospectus, and formed the Anglo-American Telegraph Company, to lay a new cable and complete the broken one. On July 13, 1866 the Great Eastern started paying out once more. Despite problems with the weather on the evening of Friday, July 27, the expedition made the entrance of Trinity Bay in a thick fog. The next morning at 9 a.m. a message from England cited these words from the leader in The Times: "It is a great work, a glory to our age and nation, and the men who have achieved it deserve to be honoured among the benefactors of their race." "Treaty of peace signed between Prussia and Austria." The shore end was landed during the day by the Medway. Congratulations poured in, and friendly telegrams were again exchanged between Queen Victoria and the United States.
On August 9 the Great Eastern put to sea again in order to grapple the lost cable of 1865, and complete it to Newfoundland.[7] They were determined to find it. There were some who thought it hopeless to try, declaring that to locate a cable two-and-a-half miles down would be like looking for a small needle in a large haystack. For days, the Great Eastern moved slowly here and there, "fishing" for the lost cable with a grapnel at the end of a stout rope. Suddenly, the cable was "caught" and brought to the surface, but while the men cheered it slipped from the grapnel's hold and vanished again. It was not until a fortnight later that it was once more fished up; then it took 26 hours to get it safely on board the Great Eastern. The cable was carried to the electrician's room where it was determined that the cable was connected. All on the ship cheered or wept as rockets were sent up into the sky to light the sea. The recovered cable was then spliced to a fresh cable in her hold, and paid out to Heart's Content, Newfoundland, where she arrived on Saturday, September 7. There were now two working telegraph lines.
Communication speeds
Initially messages were sent by an operator sending Morse code, a series of dots and dashes. The reception was very bad on the 1858 cable, and it took 2 minutes to transmit just one character (a single letter or a single number), which translates to about 0.1 words per minute. This is despite the use of a highly sensitive mirror galvanometer, a new invention of the time.
The first message on the 1858 cable took over 17 hours to transmit.[8] For the 1866 cable, the methods of cable manufacture, as well as sending messages, had been vastly improved. The 1866 cable could transmit eight words a minute[9] —over 50 times faster than the 1858 cable. Heaviside and Mihajlo Idvorski Pupin in later decades understood that the problem was an imbalance between capacitive and inductive reactance, to be solved by iron tape or by load coils. It was not until the 20th century that message transmission speeds over transatlantic cables would reach even 120 words per minute. Despite this, London had become the world centre in telecommunications. Eventually, no fewer than 11 cables radiated from Porthcurno Cable Station near Land's End and formed with their Commonwealth links a "live" girdle around the world.
Relays
The original cables were not fitted with relays, which would have amplified the signal along the way. This was because there was no practical way to power the relays. As technology advanced, intermediate relays became possible.
In fiction
- The cable is one of the many underwater landmarks observed by the Nautilus in Jules Verne’s “Twenty Thousand Leagues Under the Sea”
- The 2003 novel Signal & Noise, by John Griesemer, tells a fictionalized story of the project, including many incidents from real life.
- The novel Thunderstruck (2006) by Erik Larson discusses the transatlantic cable as part of the story of Marconi and the invention of wireless telegraphy.
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