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Great History of the First Transatlantic Cable - Connecting the World - Full Documentary

How the first cable was laid across the Atlantic. Until the first transatlantic cable was laid, the fastest communication between Europe and North America took at least a week. Halvor Moorshead describes the problems in linking the continents together. THE ONLY BATTLE OF the War of 1812 in which there were heavy casualties was the Battle of New Orleans, fought on 8 January 1815. It was a decisive victory for the US but there was one major problem: the Treaty of Ghent ending the war had been signed on 24 December 1814 -- about two weeks prior to the battle! Neither side was aware that the war was over.
This was, of course, normal for the times. News could only travel as fast as the swiftest horse or the fastest sailing ship. At the time, news rarely reached North America from Europe in under two weeks.
In the 1830s a number of experiments were being conducted in both the US and Britain on telegraphy, the early uses being confined to railroads. The first practical use however must be credited to Professor Samuel Morse, the inventor of Morse code, who sent a message via what was then known as magnetic telegraph from Baltimore to Washington. Thirty years later, history books were saying "no other invention has exercised a more beneficent influence on the welfare and happiness of the human race." After the first successful demonstration, telegraph lines were rapidly built all over Europe and North America, allowing messages to be sent virtually instantaneously.
Crossing the water presented greater problems. The cable needed to be insulated and strong, technologies that were both in their infancy. The first major undersea link, connecting England to France, was not completed until 1851 after several failed attempts.
The idea of a transatlantic cable was first proposed in 1845, only a year after the first practical demonstration, but the far greater distances and greater depths presented formidable problems. In 1856 the Atlantic Telegraph Company was registered with a capital of £350,000 (then about $1,400,000). On the American side Cyrus W. Field was the driving force; on the British side it was Charles Bright and brothers John and Jacob Brett.

The manufacture of the cable started in early 1857 and was completed in June. Before the end of July it was stowed on the American Niagara and the British Agamemnon -- both naval vessels lent by their respective governments for the task. They started at Valentia Harbor in Ireland (which was by then connected to the rest of the British Isles) on 5 August. For the first few days, everything went well but six days later, due to a mistake made with the brake which limited the rate of descent, the cable snapped. Just 380 miles had been laid.
The ships were forced to return to port. An extra 700 miles of cable was made for the second attempt which began on 25 June 1858. This time the same two ships met each other in mid-Atlantic where they joined their respective ends. The cable broke almost immediately. Again the two ships made another splice: this time they managed 40 miles before it broke again. The fourth time they had laid 146 miles before the cable was lost yet again. It was clear that this was not going to be easy!
The two ships returned to Ireland but it was decided that, despite the loss of a considerable amount of cable, they still had enough for a further attempt. On 29 July they made their fifth attempt, again starting from the mid point. This time it worked! On 5 August 1858 both ships reached their destinations -- Valentia Harbor in Ireland and Trinity Bay in Newfoundland. The two continents were joined.
On 16 August communication was established with the message "Glory to God in the highest, and on earth, peace, good will to men." Unfortunately the engineer in charge, Wildman Whitehouse, started by applying very high voltages rather than the very weak currents that had been tested during the cable laying. Within three weeks the damage inflicted on the cable by the high voltages was becoming apparent and it ceased to work.

However, although we're now laying fiber optic cables rather than copper ones, the techniques in laying and protecting the cables are still remarkable similar. The same principles are in effect. The cable is still covered with helical steel wires to protect the central core, and breaks are found by testing the resistance of the metal inside to determine the length before there's a break.

The major difference is the capacity. While the first few cables could only manage a few words per minute, modern submarine cables can transmit more like 84,000,000,000 words per second." Cable & Wireless Worldwide have plans to increase that further, with 100Gbit/s line systems expected to come online within the next 18 months -- 50,000 times greater per fiber than the first fiber optic cable that went live in 1988.

Видео Great History of the First Transatlantic Cable - Connecting the World - Full Documentary канала Wisdom Land
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20 августа 2017 г. 12:19:30
00:45:22
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