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From page 114... ...
When the boat reached the French coast, the end of the rope was attached to a wooden box equipped with brass knobs and a dial bearing the letters of the alphabet. At Dover the man running this curious operation, John Brett, attached similar equipment to the other end.
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From page 115... ...
To assemble the hundred-yard lengths into 25 miles of cable, the exposed ends of the copper wires were twisted together, and globs of warm gutta percha were applied to the joints and squeezed crudely into shape with a wooden press. This cable was not robust, to say the least.
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From page 116... ...
The following year Ezra Cornell, founder of the university, laid a line 12 miles across the Hudson, from Fort Lee to New York City. His cable had two cotton-covered copper wires wrapped in rubber, further protected by a lead sheath.
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From page 117... ...
In the end Brett gave up on London and made a deal with the French government. For his channel connection, let alone the global network he imagined, John Brett and his brother Jacob were woefully underprepared.
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From page 118... ...
They improvised by filling in the gap with a length of the old wire but a month later managed to pick up the cable at the join, splice in an additional length of the new strengthened line, and complete the job. Building on this success, the brothers Brett formed the European and American Telegraph Company and made a creditable attempt to corner the market on this new business.
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From page 119... ...
House represented years of wasted time. More mundanely, John Brett displayed a habit of packing not quite enough cable on his early expeditions.
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From page 120... ...
Despite such setbacks, John Brett established himself for a time as the leading figure in submarine cabling. When Frederick Gisborne, a globe-trotting Englishman then resident in Canada, began to think seriously of an underwater telegraph across the Atlantic Ocean, connecting the New World to the Old, it was Brett whom he first contacted.
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From page 121... ...
By this time there were enough telegraph lines around Britain and the continent that it was possible to set up test circuits in which signals traveled along hundreds or even thousands of miles of wire in the air, underground, and underwater. Experiments showed that underwater cables, and to a lesser extent underground ones, suffered a small but detectable delay in transmission.
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From page 122... ...
Nevertheless, if poorly understood electrical phenomena were already causing trouble on the 70-mile cable from England to Holland, the prospects for a link of 2,000 miles or more across the Atlantic Ocean must be questionable. The problem finally came to Thomson's attention in a roundabout way.
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From page 123... ...
and John Thomson (not William's deceased brother John, obviously, but a son of the other William Thomson, the medical professor)
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From page 124... ...
The consequence, Thomson showed, was that a sharp pulse applied at one end spread out, as it moved along, into a rolling wave of increasing length. Thomson obtained the curious result that the arrival time of this changing signal, if measured by the moment the crest of the wave reached the far end, increased with the square of the distance traveled.
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From page 125... ...
Attending the British Association meeting in 1855, in Glasgow, Whitehouse heard Thomson announce the law of squares. At the BA the following year he recounted his own tests of signal transmission through cables of various lengths, which he claimed contradicted this supposed law.
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From page 126... ...
Without describing in any detail what exactly he measured, he claimed the transmission time was proportional to the length of the cables he tested, not the square of the length. This boded well for the Atlantic project, he said, and he concluded with an airy dismissal of Thomson's so-called theory of the telegraph, implying that ivory-tower academics shouldn't meddle in the affairs of practical men: "And what, I may be asked, is the general conclusion to be drawn as the result of this investigation of the law of squares applied to submarine circuits?
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From page 127... ...
For the time being, the exchange between Thomson and Whitehouse concluded with protestations of good will on both sides and acknowledgment by both that anyone proposing to build an Atlantic cable would be wise to test and investigate thoroughly before proceeding with so ambitious and expensive a project. Cyrus Field was just the man not to do this.
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From page 128... ...
Field contacted Morse, who assured him blithely that no serious technical problems stood in the way of an Atlantic cable. While Matthew Field and Gisborne toiled away in the distant wastes of eastern Canada, Cyrus Field took over the project, formed a consortium, raised money, and in 1855 sailed for England to meet John Brett, who at that time could claim the greatest success and expertise in the laying of submarine cables.
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From page 129... ...
He obtained conflicting advice from Whitehouse, Thomson, and Faraday about the delay and distortion inherent in undersea transmission. In October he formed the Atlantic Telegraph Company, with Brett as president, himself as vice-president, Bright as chief engineer, and Whitehouse (who now gave up his Brighton medical practice altogether)
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From page 130... ...
, but Whitehouse, with his more optimistic view of signal transmission, saw no problem. On his own initiative, Thomson embarked on a study of the quality of copper supplied by several British foundries and to his alarm found that the electrical resistance of copper wire of the same alleged gauge and purity varied in some cases by more than a factor of two.
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From page 131... ...
In his paper on the quality of commercial copper, he said he "was surprised tO find differences between different specimens so great as most materially to affect their value in the electrical operations for which they are designed" and argued "how important it is to shareholders in submarine telegraph companies that only the best copper wire should be
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From page 132... ...
Thomson's determination on this point thus led to the first scientifically informed quality control system for the manufacture of a commercial product. As he later commented, "It was not until practical testing to secure high conductivity had been commenced in the factory, that practical men came thoroughly to believe in the reality of the differences of conductivity in the different specimens of copper wire, all supposed good and supplied for use in submarine cables." A second matter on which Whitehouse was complacent and Thomson nervous was that signaling across the Atlantic placed new demands on the sensitivity of the receiver.
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From page 133... ...
Having made a prototype, he requested the substantial sum of £2,000 from the Atlantic Telegraph Company to build a number of instruments for use with the cable to be laid later that year. The directors, yielding to Whitehouse's opinion, turned him down, but later he managed to get £500, along with permission to test the mirror galvanometer during the voyage.
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From page 134... ...
But Whitehouse was still chief electrician and Thomson an unpaid adviser. Both appeared eager to travel with the 1858 cabling voyage, Thomson because he wanted to demonstrate the virtues of his mirror galvanometer, Whitehouse to prove he was in charge.
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From page 135... ...
But many of the financiers, who had by now seen hundred of thousands of dollars slip to the bottom of the sea, were ready to wrap up the Atlantic Telegraph Company and label the entire enterprise a noble failure. Field, the consummate salesman, prevailed again, and by the end of luly the fleet, recoaled and reprovisioned, was back in the middle of the Atlantic.
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From page 136... ...
He waited anxiously "in a perfect fever of nervous excitement, shaking like an aspen leaf, yet in mind clear and collected, testing and waiting, with a halfdespairing look for the result." So he and Bright and the rest waited, in dread of another failure. At one point someone saw the light spot from the mirror galvanometer twitch through an unmistakable 40 degrees, but Thomson, dashing into the operations room, saw nothing.
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From page 137... ...
" In London the board of the Atlantic Telegraph Company was growing similarly restless. Thomson had left Ireland a few days after landing, and Whitehouse, still insisting on the need for unspecified adjustments, refused to say what he was doing in the telegrapher's hut at Valentia.
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From page 138... ...
. &c., &c., &c." The Post remained more skeptical, editorializing thus: "True, the Queen's message bears no date, neither do we have any intimation of the time it has taken to transmit it whether an hour, day, or week nevertheless, we are assured, upon the faith of the Atlantic Telegraph Company, that it was actually transmitted from Ireland to Newfoundland by a submarine electric telegraph." Then in succeeding days came actual news.
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From page 139... ...
Days went by when nothing came through. Ordering an investigation, the board of the Atlantic Telegraph Company managed to pry Whitehouse from his station in Valentia.
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From page 140... ...
This was the old cable, hastily manufactured to a poor design for the 1857 expedition, then stored through the following winter in tanks of water at Plymouth. The following summer Field wrote to Thomson to say that on examining some cutup sections of the cable that he had sold to Tiffany's in New York as mementos, he found that in places the copper wire was distinctly off center, in some cases almost piercing through the gutta percha to the surrounding layer of tarred hemp.
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From page 141... ...
Thomson wrote privately to all parties, making clear that Whitehouse was now telling falsehoods in particular, he claimed that the president's reply to Queen Victoria was received on one of his devices, whereas in fact it came through Thomson's mirror galvanometer. Official statements from the Atlantic Telegraph Company made plain their confidence in Thomson and utter distrust of Whitehouse.
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From page 142... ...
Galvanometers, including Thomson's ultrasensitive mirror galvanometer, did not strictly speaking measure electric currents. Rather, a current passing through the device made a needle or a light beam swing, but how much it would swing in response to a given current varied from
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From page 143... ...
Telegraph engineers learned a number of tricks for locating faults in an underwater cable. The simplest case was an outright failure such that the sea came into contact with bare copper, effectively earthing the wire at some unknown position.
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From page 144... ...
Weber had also set out an alternative system, based on the force between magnets rather than charges. Permanent magnets were no more stanclarclizecl or controllable than static electric charges, but Weber observecl that a current passing through a coil of known dimensions would create an electromagnet that would feel a measurable force from the earth's magnetic fielcl.
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From page 145... ...
So elaborate a procedure, difficult enough for laboratory scientists, was far beyond the expertise of the telegraph engineers and technical men who actually needed standard measurements. At the 1861 British Association meeting in Manchester, the veteran telegraph engineers Charles Bright and Latimer Clark made a plea for the adoption of standardized measures that telegraphers had devised.
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From page 146... ...
Nevertheless, Bright and Clark refused at first to serve on the committee, though they joined after a year or two. Their eagerness tO take part had been deflected when the nascent committee, at Thomson's urging especially, agreed to use Weber's magnetic system as a theoretical foundation and refer any practical measurements, such as the telegraphers preferred, to these absolute standards.
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From page 147... ...
He had earlier sailed with John Brett on the cabling voyage from Sardinia to Africa. lenkin, careful and assiduous, strove to instill the notion of quality control in technical manufacturing as insistently as Thomson had done.
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From page 148... ...
(The modern British Institution of Electrical Engineers began life in 1871 as the Society of Telegraph Engineers.) Neither Bright nor Clark nor lenkin had any formal university education in the technical applications of electrical science; no such course was available to them.
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From page 149... ...
In fact, discrepancies among these standards, as well as in comparison to lacobi's old standard, to resistances that Weber himself had made, and to the mercury column favored by Siemens, existed at the level of five percent or more for many years. By virtue of the BA's scientific influence as well as the leading role that British manufacturers played in the telegraph industry, the BA unit 4This is best regarded as a purely algebraic equivalence, arising from the way electrical measurements are derived ultimately from a force measurement.
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From page 150... ...
When I have lived here for a full year, I will be spoilt for Germany for the rest of my life." So it was. He stayed in England, became a British citizen, anglicized his name to William, took up telegraphic and electrical engineering in earnest, and became an acquaintance of William Thomson.
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From page 151... ...
F Varley, another veteran of the Atlantic cable voyages, wrote to Thomson suggesting ampere for the strength of a magnetic pole, in order to get a Frenchman into the picture, and added: "I object to Galvad because Galvani discovered next to nothing." Varley also disliked Clark's names for the multiples, on the grounds, among other things, that Fleeming Jenkin "writes so badly that .
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From page 152... ...
Speaking to the Institution of Electrical Engineers in London in 1883, Thomson portrayed the saga of the BA unit as a victory in the long term, with the mercury standard an interim solution until the wrinkles were worked out. Thomson's effort in setting electrical measurements on a trustworthy theoretical foundation represents one of the most influential if little known achievements of his career.
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From page 153... ...
It was in the following winter that Professor Thomson met with the accident which lamed him for life." This was in 1859, when Thomson was only 35 years old but already a powerful figure in the British scientific community, an authority on every aspect of physics, and with the beginnings of a public reputation after his adventures with the Atlantic cable voyages and the noisy dispute with Whitehouse. The business of telegraphy claimed an increasing part of his life.
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From page 154... ...
His scientific publications proceeded apace, but their character changed. He wrote numerous short notes on problems of telegraphy, on the properties of copper and other conductors, on varied phenomena in electrical induction and transmission and the like, on the mechanical stresses on a cable dangling from the end of a ship, and so on.
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From page 155... ...
He began to enjoy the company of engineers and men of business. His patent on the mirror galvanometer and other innovations brought him money.
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From page 156... ...
A number of British financiers and entrepreneurs became interested in the Atlantic project, but as Thomson said later, "Cyrus Field, from the other side of the Atlantic, helped keep it alive; he gave help and impulse where they were required; worked with those who did not require revivification; and he, with his English colleagues, revived the undertaking in 1865." In 1859 the British government had set up a formal parliamentary inquiry into the failure of the 1858 cable. During 22 hearings over a period of nine months, testimony came from scientists, engineers, oceanographers, manufacturers, and electricians.
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From page 157... ...
Thomson's goal was always to enlist technology in support of systems that ordinary men could operate with confidence. In his history of the subject, Charles Bright credited Thomson's improved mirror galvanometer as an essential factor in the ultimate success of the telegraph to India.
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From page 158... ...
It was getting the cable over the stern of the ship and safely down to the seabed that continued to pose the greatest difficulties. Enthusiastic amateurs suggested suspending an Atlantic cable from buoys so that it ran only 50 or 100 feet below the surface, or even dangling it from an array of hot-air balloons to avoid the water altogether.
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From page 159... ...
He now struck a deal with Cyrus Field and the Atlantic Telegraph Company. In return for £50,000 in ATC shares, he agreed to use the Great Eastern' to lay an Atlantic cable, with his company bearing all operating costs and handing the cable over to Field only after a successful voyage.
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From page 160... ...
The Great Eastern' plodded serenely on through heavy seas, "steady as a Thames steamer," the cable unreeling smoothly over the stern. About two-thirds of the way across, 600 miles from Newfoundland, detection of another fault brought the ships to a halt.
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From page 161... ...
"I am very pleased to learn that you are again in this country. You are not come too soon as the LAtlantic Telegraph Company]
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From page 162... ...
Old shares of the Atlantic Telegraph Company finally began to pay dividends. The cables of 1865 and 1866 lasted, in fact, only a few years.
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From page 163... ...
At the age of 42, in honor of his extended efforts in bringing the transatlantic cable to reality, Thomson became Sir William Thomson. To his colleagues in the academic world, it might have seemed that he had abandoned his true calling, but so far as Sir William was concerned, the technology of the telegraph was science in action.
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