The Story of the Atlantic Cable. Sir Charles Bright
was actually carried away by the strong tidal currents and even broken into pieces during laying. In the third endeavor, between the same two points, the arrangements for checking the cable while paying out being again inadequate, there was not sufficient to reach the farther shore. However, in 1853, a heavy cable, weighing 7 tons per mile, with six conductors, was successfully laid for the Magnetic Telegraph Company by the late Sir Charles Bright.[7] This was in upward of 180 fathoms—the deepest water in which a cable was laid for some time—and proved a permanent success, forming the first establishment of telegraphic communication with Ireland. Only a year elapsed before it became evident that another cable was required to meet the traffic between England and the Continent, and an additional line was laid from Dover to Ostend. Anglo-Dutch and Anglo-German cables followed in due course; and in less than ten years from the commencement of its operations over the first Channel cable, the Submarine Telegraph Company (since absorbed by the state) was working at least half a dozen really excellent cables, varying from 25 to 117 miles in length, connecting England with the rest of Europe. During the next few years submarine communication was established between Denmark and Sweden, as well as between Italy, Corsica, and Sardinia; and between Sardinia and{23} the north coast of Africa; but where successful, the measures adopted were, in the main, similar to those we have already described in connection with the preceding lines, though special conditions were, in some instances, the means of introducing certain modifications and improvements. Several serious failures were, however, experienced in the deep water of the Mediterranean which had a detracting effect—in the public mind—on the chances of the great undertaking which was to follow.
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PART II
THE PIONEER LINE
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CHAPTER I
EVOLUTION OF ATLANTIC TELEGRAPHY IN AMERICA AND ENGLAND
Gradual Evolution—The Projectors—Survey of the Route—Soundings—Nature of the Ocean Bed—Formation of the Atlantic Telegraph Company—Raising Capital—Critics, “Croakers,” and Crude Inventors.
As has been shown in the introductory chapter, the efforts of the early projectors of submarine telegraphy were at first confined to connecting countries divided only by narrow seas, or establishing communication between points on the same seaboard. The next step forward, with which we are here immediately concerned—that of spanning the Atlantic Ocean between Europe and America—was aptly characterized at the time as “the great feat of the century.” By its means the people of the two great continents were to speak together in a few moments, though separated by a vast ocean.
This was the first venture in transoceanic telegraphy. There was no applicable data to go upon; for the vast difference between laying short cable-lengths across rivers, bays, etc., in shallow water, and that of laying a long length of cable in depths of over two miles across an open ocean will be easily recognized—at any rate, by the sailor and engineer.
The wires of the Magnetic Telegraph Company{28} had already been carried to various points on the west and south coast of Ireland; and, in 1852, Mr. F. N. Gisborne, a very able English engineer, obtained an exclusive concession for connecting St. Johns, Newfoundland, with Cape Ray, in the Gulf of St. Lawrence, by an overhead telegraph-line. The idea was to “tap” steamers coming from London to Cape Race at St. Johns, and pass messages between that point and Cape Breton, on the other side of the Gulf, by carrier-pigeons. A few miles of cables were made in England, and laid between Prince Edward Island and New Brunswick. Mr. Gisborne then surveyed the route for the land-line across Newfoundland, and had erected some forty miles of it, when the work was stopped for want of funds. When in New York in 1854, Gisborne was introduced to Mr. Cyrus West Field, a retired merchant, who became enthusiastic on the subject, and formed a small, but strong, syndicate for the practical realization of Gisborne’s scheme. A cable eighty-five miles in length was made in England, to be laid between Cape Breton and Newfoundland; but after forty miles had been paid out, rough weather ensued, and the undertaking had to be abandoned. A fresh instalment was, however, sent out in 1856, and successfully laid across the Gulf, thus connecting St. Johns with Canada and the American lines. The conductor of this line instead of being a single solid wire was, for the first time, composed of several small wires laid up together in strand form—with a view to avoiding a flaw in any single wire stopping the conductivity, besides affording increased mechanical pliability.{29}
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The feasibility of uniting the two vast systems of telegraphy had engaged the consideration of some of those most prominently associated with electric telegraphy on both sides of the Atlantic. It had been already shown that cables could be successfully laid and maintained in comparatively moderate depths in the Mediterranean, Black Sea, etc., but the nearest points between the British Isles and Newfoundland are nearly 2,000 miles apart. The greatest length of submarine line which had hitherto been effectively submerged—110 miles—formed but an insignificant portion of such an enormous distance; and that, too, involving a depth of nearly three miles for a large proportion of the way, instead of about 300 fathoms.
Apart from the engineering difficulties entailed by this vast distance and depth, the question was then undetermined as to the possibility of conveying electric currents through such a length in an unbroken circuit, and at a speed that would enable messages to be passed rapidly enough in succession to prove remunerative. Various researches had been made—by Faraday among others—with a view to determining the law in relation to the velocity of electricity through a conducting-wire.
The retarding effect of the insulating covering had already been discovered; but the exact formula for the working speed of cables of definite proportions and lengths was not correctly arrived at till some years later. The similarity, in principle, of a cable to a Leyden jar was first pointed out by Mr. Edward Brailsford Bright in the course of a paper read before the British Association{31} in 1854. He showed that on charging a gutta-percha-covered wire, the insulating material tended to absorb and retain a part of the charge and to hold back, as a static charge, some of the electricity flowing as current through the conductor—just as the charge (of opposite potential) induced on the outside plate of a Leyden jar statically holds the primary charge on the inner plate, until either are neutralized. The brothers, Edward and Charles Bright, made a series of extensive experiments on long lengths of underground wires; and these investigations were supplemented later by Mr. Edward Orange Wildman Whitehouse (formerly a medical practitioner), who became electrician to the first Atlantic cable. Mr. Whitehouse was a man of very high intellectual and scientific attainments, and a most ingenious and painstaking experimenter.
The retardation of the electric current through an insulated wire due to induction—a phenomenon practically unknown with bare, aerial wires suspended on posts, and of no consequence with quite short cables—was overcome by using a succession of opposite currents. By this means the latter, or retarded, portion of each current was “wiped out” by the opposite current immediately following it; and thus a series of electric waves could be made to traverse the cable, one after the other, several being in the act of passing onward at different points along the conductor at the same time. The Messrs. Bright devised a special key (embodied with a patent for signaling through long cables) for transmitting these alternating currents from the battery; and this was followed by others to effect the same object—one{32} by Professor Thomson (now Lord Kelvin), who became electrical adviser to the enterprise.