The Battery and the Boiler: Adventures in Laying of Submarine Electric Cables. Robert Michael Ballantyne
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his letter of introduction from Mr Smith, Robin was conducted over the premises by a clerk, who, under the impression that he was a very youthful and therefore unusually clever newspaper correspondent, treated him with marked respect. This was a severe trial to Robin’s modesty; nevertheless he bore up manfully, and pulling out his note-book prepared for action.
The reader need not fear that we intend to inflict on him Robin’s treatise on what he styled the “Great Atlantic Cable,” but it would be wrong to leave the subject without recording a few of those points which made a deep impression on him.
“The cable when completed, sir,” said the clerk, as he conducted his visitor to the factory, “will be 2300 nautical miles in length.”
“Indeed,” said Robin, recording the statement with solemn gravity and great accuracy; “but I thought,” he added, “that the exact distance from Ireland to Newfoundland was only 1600 miles.”
“You are right, sir, but we allow 700 miles of ‘slack’ for the inequalities of the bottom. Its cost will be 700,000 pounds, and the whole when finished will weigh 7000 tons.”
Poor Robin’s mind had, of course, been informed about ton-weights at school, but he had not felt that he realised what they actually signified until the thought suddenly occurred that a cart-load of coals weighed one ton, whereupon 7000 carts of coals leaped suddenly into the field of his bewildered fancy. A slightly humorous tendency, inherited from his mother, induced 7000 drivers, with 7000 whips and a like number of smock-frocks, to mount the carts and drive in into the capacious hold of the Great Eastern. They turned, however, and drove instantly off his brain when he came into the august presence of the cable itself.
The central core of the cable—that part by which the electric force or fluid was to pass from the Old World to the New, and vice versa, was made of copper. It was not a solid, single wire, but a strand composed of seven fine wires, each about the thickness of a small pin. Six of these wires were wound spirally round the seventh. This was in order to prevent what is termed a “breach of continuity,” for it will be at once perceived that while a single wire of the core might easily break in the process of laying the cable, and thereby prevent the flow of electricity, the probability of the seven small wires all breaking at the same spot was so remote as to be almost impossible, and if even one wire out of the seven held, the continuity would remain. Nay, even all the seven might break, but, so long as they did not all break at the same place, continuity would not be lost, because copper would still continue to touch copper all throughout the cable’s length.
In the process of construction, the central wire of the copper core was first covered with a semi-liquid coating of gutta-percha, mixed with tar—known as “Chatterton’s Compound.” This was laid on so thick that when the other wires were wound round it all air was excluded. Then a coating of the same compound was laid over the finished conductor, and thus the core was solidified. Next, the core was surrounded with a coating of the purest gutta-percha—a splendid non-conductor, impervious to water—which, when pressed to it, while in a plastic state, formed the first insulator or tube to the core. Over this tube was laid a thin coat of Chatterton’s Compound for the purpose of closing up any small flaws or minute holes that might have escaped detection. Then came a second coating of gutta-percha, followed by another coating of compound, and so on alternately until four coats of compound and four of gutta-percha had been laid on.
This core, when completed, was wound in lengths on large reels, and was then submerged in water and subjected to a variety of severe electrical tests so as to bring it as near as possible to a state of perfection, after which every inch of it was examined by hand while being unwound from the reels and re-wound on the large drums on which it was to be forwarded to the covering works at East Greenwich, there to receive its external protecting sheath.
All this, and much more besides, did Robin Wright carefully note down, and that same evening went home and delivered a long and luminous lecture, over which his mother wondered, Madge rejoiced, his father gloried, and uncle Rik fell asleep.
Next day he hastened to the covering works, and, presenting his credentials, was admitted.
Here he saw the important and delicate core again carefully tested as to its electrical condition, after which it received a new jacket of tanned jute yarn to protect it from the iron top coat yet to come. Its jute jacket on, it was then coiled away in tanks full of water, where it was constantly kept submerged and continuously tested for insulation. Last of all the top coat was put on. This consisted of ten wires of peculiarly fine and strong iron. Each of these ten wires had put on it a special coat of its own, made of tarred Manilla yarn, to protect it from rust as well as to lighten its specific gravity. The core being brought from its tank, and passed round several sheaves, which carried it below the factory floor, was drawn up through a hole in the centre of a circular table, around the circumference of which were ten drums of the Manilla-covered wire. A stout iron rod, fastened to the circumference of the table, rose from between each drum to the ceiling, converging in a cone which passed through to the floor above. Our core rose in the middle of all, and went through the hollow of the cone. When all was put in noisy and bewildering motion, the core which rose from the turning-table and whirling drums as a thin jute-clad line, came out in the floor above a stout iron-clad cable, with a Manilla top-dressing, possessing strength sufficient to bear eleven miles of its own length perpendicularly suspended in water—or a margin of strength more than four and a half times that required,—and with a breaking strain of seven tons fifteen hundredweight.
When thoroughly charged and primed, Robin went off home to write his treatise.
Then he received the expected summons to repair on board the Great Eastern, and bade adieu to his early home.
It was of no use that Robin tried to say good-bye in a facetious way, and told Madge and his mother not to cry, saying that he was only going across the Atlantic, a mere fish-pond, and that he would be home again in a month or two. Ah! these little efforts at deception never avail. Himself broke down while urging Madge to behave herself, and when his mother gave him a small Bible, and said she required no promise, for she knew he would treasure and read it, he was obliged hastily to give her a last fervent hug, and rush from the house without saying good-bye at all.
Chapter Seven.
The Big Ship—First Night Aboard
When our hero at last reached the Great Eastern, he soon found himself in what may be termed a lost condition. At first he was disappointed, for he saw her at a distance, and it is well-known that distance lends deception as well as “enchantment to the view.” Arrived alongside, however, he felt as if he had suddenly come under the walls of a great fortress or city.
Presently he stood on the deck of the Big Ship, as its familiars called it, and, from that moment, for several days, was, as we have said, in a lost condition. He was lost in wonder, to begin with, as he gazed at the interminable length and breadth of planking styled the deck, and the forest of funnels, masts, and rigging, and the amazing perspective, which caused men at the further end from where he stood to look like dolls.
Then he was lost in reality, when he went below and had to ask his way as though he were wandering in the labyrinths of a great city. He felt—or thought he felt—like a mere mite in the mighty vessel. Soon he lost his old familiar powers of comparison and contrast, and ere long he lost his understanding altogether, for he fell down one of the hatchways into a dark abyss, where he would probably have ended his career with electric speed if he had not happily fallen into the arms of a human being, with whom he rolled and bumped affectionately, though painfully, to the bottom of the stair.
The human being, growled intense disapprobation during the process, and Robin fancied that the voice was familiar.
“Come, I say,” said the being, remonstratively, “this is altogether too loving, you know. Don’t squeeze quite so tight, young ’un, whoever you be.”
“Oh, I beg your pardon,” gasped Robin, relaxing his grasp when they stopped rolling; “I’m so sorry. I hope I haven’t hurt you.”
“Hurt me!” laughed Jim Slagg, for it was he; “no, you small electrician, you ’aven’t got battery-power enough to do me much