In our instantanous world of cell phones, internet access, and satellite television, it's almost impossible to understand how isolated the world was at this time. Overseas news took weeks to come across the ocean from Europe, Asia, South America and Africa. Ships transporting news were often lost at sea. So this article about the laying of the first Atlantic cable is an event as wondrous as when the first satellites were launched for television and radio service.I believe that the youngsters in our family consider my study a very pleasant room. There are some books, pictures, and hunting implements in it, and I have quite a large number of curious things stored in little mahogany cabinets, including a variety of specimens of natural history and articles of savage warfare, which have been given to me by sailors and travelers. In one of these cabinets there are the silver wings of a flying-fish, the poisoned arrows of South Sea cannibals, sharks' and alligators' teeth, fragments of well-remembered wrecks, and an inch or two of thick tarred rope.
The latter appears to be a common and useless object at the first glance, but when examined closely it is not so uninteresting. It measures one and one-eighth of an inch in diameter, and running through the center are seven bright copper wires, surrounded by a hard, dark brown substance, the nature of which you do not immediately recognize. It is gutta-percha, the wonderful vegetable juice, which is as firm as a rock while it is cold and as soft as dough when it is exposed to heat. This is inclosed within several strands of Manilla hemp, with ten iron wires woven among them. The hemp is saturated with tar to resist water, and the wires are galvanized to prevent rust. You may judge, then, how strong and durable the rope is, but I am not sure that you can guess its use.
Near the southern extremity of the western coast of Ireland there is a little harbor called Valentia, as you will see by referring to a map. It faces the Atlantic Ocean, and the nearest point on the opposite shore is a sheltered bay prettily named Heart's Content, in Newfoundland. The waters between are the stormiest in the world, wrathy with hurricanes and cyclones, and seldom smooth even in the calm months of midsummer. The distance across is nearly two thousand miles, and the depth gradually increases to a maximum of three miles. Between these two points of land—Valentia in Ireland and Heart's Content in Newfoundland—a magical rope is laid, binding America to Europe with a firm bond, and enabling people in London to send instantaneous messages to those in New York. It is the first successful Atlantic cable, and my piece was cut from it before it was laid. Fig. 2 shows how a section of it looks, and Fig. 3 shows a section of the shore ends, which are larger.
SECTIONS OF CABLES (REDUCED). 1. Main cable of 1858. 1a. Shore end, abandoned cable of 1858. 2. Main cable of 1866. 2a. Shore-end, recovered cable of 1865. 3. Shore end of cable of 1866.Copper is one of the best conductors of electricity known, and hence the wires in the center are made of that metal. Water, too, is an excellent conductor, and if the wires were not closely protected, the electricity would pass from them into the sea, instead of carrying its message the whole length of the line. Therefore, the wires must be encased or insulated in some material that will not admit water and is not itself a conductor. Gutta-percha meets these needs, and the hemp and galvanized wire are added for the strength and protection they afford to the whole.
It was an American who first thought of laying such an electric cable as this under the turbulent Atlantic. Some foolish people laughed at the idea and declared it to be impracticable. How could a slender cord, two thousand miles long, be lowered from an unsteady vessel to the bottom of the ocean without break? It would part under the strain put upon it, and it would be attacked by marine monsters, twisted and broken by the currents. At one point the bed of the sea suddenly sinks from a depth of two hundred and ten fathoms to a depth of two thousand and fifty fathoms. Here the strain on the cable as it passed over the ship's stern would be so great that it certainly must break. More than this, the slightest flaw—a hole smaller than a pin's head—in the gutta-percha insulator would spoil the entire work, and no remedy would be possible. A great many people spoke in this way when the Atlantic cable was first thought of, as others, years before, had spoken of Watt and Stephenson. But Watt invented the steam-engine, Stephenson invented the locomotive, and Cyrus Field bound Great Britain to the United States by telegraph.
Early in 1854, Mr. Field's attention was drawn to the scheme for a telegraph between Nova Scotia and Newfoundland, in connection with a line of fast steamships from Ireland to call at St. John's, Newfoundland. The idea struck him that if a line were laid to Ireland, lasting benefit would result to the world. So he called together some of his intimate friends, including Peter Cooper, Moses Taylor, Chandler White, and Marshall O. Roberts, and they joined him in organizing the "New York, Newfoundland, and London Telegraph Company," which was the pioneer in the movement to connect the two continents by a telegraph cable, and without whose aid its consummation would have been indefinitely delayed.
The work was costly and difficult. The first part consisted in surveying the bottom of the sea for a route. This was done by taking "soundings" and "dredgings." As some of you are aware, "sounding" is an operation for ascertaining the depth of the sea, while "dredging" reveals what plants and living creatures are at the bottom. After much patient labor, a level space was found between Ireland and Newfoundland, and it seemed to be so well adapted to the surveyor's purposes that it was called the "Telegraphic Plateau."
Two or three large vessels were next equipped, and sent out with several thousand miles of cable on board, which they proceeded to lay. But the fragile cord—fragile compared with the boisterous power of the waves—broke in twain, and could not be recovered. A second attempt was made, and that failed, too. Brave men can overcome adversity, however, and the little band of scientific men and capitalists were brave men and were determined to succeed. Each heart suffered the acute anguish of long-deferred hope, and each expedition cost many hundred thousands of dollars. Nevertheless, the promoters of the Atlantic cable sent out a third time, and when failure met them again, it seemed to common minds that their scheme was a settled impossibility. Not so with the heroes. Each failure showed them some faults in their plans or machinery. These they amended. Thus, while they were left at a distance from the object of their ambition, they were brought a little nearer to its attainment.
Guided by the light of past experience, they equipped a fourth expedition. The "Great Eastern" was selected, and her interior was altered for the purpose. She was, and is still, the largest vessel afloat. Her length is six hundred and ninety-five feet; her breadth eighty-five feet, and her burthen twenty-two thousand tons. One of the principal causes of failure in previous expeditions was the inability of the cable to endure the severe strain put upon it in stormy weather as it passed from an ordinarily unsteady vessel into the sea. The "Great Eastern," from her immense size, promised to be steady in the worst of gales. Her hold was fitted with three enormous iron tanks—-a "fore" tank, a "main" tank, and an "after" tank. The main tank was the largest, and eight hundred and sixty-four miles of cable were coiled in it. Eight hundred and thirty-nine miles in addition were coiled in the after tank, and six hundred and seventy miles in the fore tank, making in all two thousand three hundred and seventy-four miles of cable. The food taken on board for the long voyage in prospect consisted of twenty thousand pounds of butcher-meat, five hundred head of poultry, one hundred and fourteen live sheep, eight bullocks, a milch cow, and eighty tons of ice.
What is called the shore-end of the cable—i.e., that part nearest the shore, which is thicker than the rest—was first laid by a smaller steamer. It extended from Valentia to a point twenty-eight miles at sea. Here it was buoyed, until the great ship arrived. On a wet day in July, 1866, it was joined with the main cable on board the "Great Eastern," and on the same day that vessel started on her voyage to Newfoundland.
It may seem a simple matter to distribute or "pay out" the cable, but in practice it is exceedingly difficult. Twenty men are stationed in the tank from which it is issuing, each dressed in a canvas suit, without pockets, and in boots without nails. Their duty is to ease each coil as it passes out of the tank, and to give notice of the marks painted on the cable one mile apart. Near the entrance of the tank it runs over a grooved wheel and along an iron trough until it reaches that part of the deck where the "paying out" machine is placed. The latter consists of six grooved wheels, each provided with a smaller wheel, called a "jockey," placed against the upper side of the groove so as to press against the cable as it goes through, and retard or help its progress. These six wheels and their jockeys are themselves controlled by brakes, and after it has been embraced by them the cable winds round a "drum" four times. The drum is another wheel, four feet in diameter and nine inches deep, which is also controlled by powerful brakes; and from it the cable passes over another grooved wheel before it gets to the "dynamometer" wheel. The dynamometer is an instrument which shows the exact degree of the strain on the cable, and the wheel attached to it rises and falls as the strain is greater or less. Thence the cable is sent over another deeply grooved wheel into the sea.
You will remember what I said about insulation,—how a tiny hole in the gutta-percha would allow the electricity to escape. On deck there is a small house, which is filled with delicate scientific instruments. As the cable is paid out, it is tested here. If a wire or a nail or a smaller thing is driven through it, and the insulation is spoiled, an instrument called the galvanometer instantly records the fact, and warning is given at all parts of the ship. The man in charge touches a small handle, and an electric bell rings violently in the tank and at the paying-out machinery. At the same time a loud gong is struck, at the sound of which the engines are stopped. Delay might cause much trouble or total failure, as the injured section must be arrested and repaired before it enters the water.
The great steamer went ahead at the rate of five nautical miles an hour, and the cable passed smoothly overboard. Messages were sent to England and answers received. The weather was bright, and all hands were cheerful. On the third day after the "splicing" of the shore-end with the main cable, that part of the ocean was reached where the water suddenly increases in depth from two hundred and ten fathoms to two thousand and fifty. One of the earlier cables broke at this place and was lost forever. The electricians and engineers watched for it with anxious eyes. It was reached and passed. The black cord still traveled through the wheels unbroken, and the test applied by the galvanometer proved the insulation to be perfect. The days wore away without mishap until the evening of July 17, when the sound of the gong filled all hearts with a sickening fear.
The rain was falling in torrents and pattering on the heavy oil-skin clothing of the watchers. The wind blew in chilly gusts, and the sea broke in white crests of foam. A dense and pitchy cloud issued from the smoke-stacks. The vessel advanced in utter darkness. A few lights were moving about, and shadows fell hither and thither as one of the hands carried a lantern along the sloppy deck. The testing-room was occupied by an electrician, who was quietly working with his magical instrument, and the cable could be heard winding over the wheels astern, as the tinkling of a little bell on the "drum" recorded its progress.
The electrician rose from his seat suddenly, and struck the alarum. The next instant each person on board knew that an accident had happened. The engines were stopped and reversed within two minutes. Blue-lights were burned on the paddle-boxes, and showed a knot in the cable as it lay in the trough.
Two remedies seemed possible. One was to cut the cable, and support one end in the water by a buoy until the rest could be unraveled. The other was to unravel the cable without cutting it.
It is a very intricate knot that an old sailor cannot untie, and the old sailors on the "Great Eastern" twisted and untwisted coil after coil until they succeeded in untying this one. The insulation remained perfect, and in a few hours all was right again. The accident caused much ill foreboding, however, as it showed how slight an occurrence might bring the expedition to a disastrous end.
On July 27, after a voyage of fifteen days, the "Great Eastern" finished her work, and her part of the cable was attached to the American shore-end, which had been laid by another vessel. Some of you will remember the rejoicings in the United States over the event. It surpassed all other achievements of the age, and equaled the invention of the telegraph itself.
Thus, after infinite labor and repeated failures, the brave men who undertook the work accomplished it. A year before, their third cable had broken in mid-ocean, and it was now proposed to "grapple" for it. The "Great Eastern" was fitted out with apparatus, which may be likened to an enormous fishing-hook and line, and was sent to the spot where the treasure had been lost. The line was of hemp interwoven with wire. Page 328 shows a section of it. Twice the cable was seized and brought almost to the surface. Twice it slipped from the disappointed fishermen, but the third time it was secured. It was then united with the cable on board, which was "paid out" until the great steamer again reached Newfoundland, and a second telegraph-wire united the two continents.
The scene on board as the black line appeared above water was exciting beyond description. It was first taken to the testing-room, and a signal intended for Valentia was sent over it, to prove whether or not it was perfect throughout its whole length. If it had proved to be imperfect, all the labor spent upon it would have been lost. The electricians waited breathlessly for an answer. The clerk in the signal-house at Valentia was drowsy when their message came, and disbelieved his ears. Many disinterested people, and even some of the promoters of the cable, did not think it possible to recover a wire that had sunk in thousands of fathoms of water. But the clerk in the little station connected with the shore-end of the cable of 1865 suddenly found himself in communication with a vessel situated in the middle of the Atlantic.
The delay aggravated the anxious watchers on the ship, and a second signal was sent. How astonished that simple-minded Irish telegraph-operator was! Five minutes passed, and then the answer came. The chief electrician gave a loud cheer, which was repeated by every man on board, from the captain down to his servant.
There are now four cables in working order, and the cost of messages has been reduced twenty-five per cent. The New York newspapers now contain nearly as much European news as the London newspapers themselves.
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