Once a Week (magazine)/Series 1/Volume 8/The Atlantic telegraph
THE ATLANTIC TELEGRAPH.
Every now and then people ask what has become of the Atlantic Telegraph. The City man, passing by Old Broad Street, still sees the office of the company, and hears that a staff is still maintained there; that there are directors, and a chairman, who every now and then meet, pass resolutions, and draw up fresh proposals. The question is not, therefore, so absurd a one as it may appear, for surely all this expensive machinery would not be maintained, if the scheme had perished, as it has long been admitted on all hands the cable itself has. It is dead by no means, and after the disastrous failure which took place four years ago, we see evident signs of real efforts to accomplish this great design.
That the second cable that crosses the Atlantic will be as great a success as the former one was a melancholy failure, no electrician of eminence any longer doubts. That the first cable was a failure in fact, was owing to causes so clearly traceable to the grossest negligence, that the wonder is not that it failed, but that it survived to give utterance to those few words which prove that it retained life after its bad treatment and perilous voyage. Let us recount a few of them. At the time of its manufacture, the working of the new material, gutta percha, was, so to say, a new art, and the material in itself so bad in quality, owing to the tricks played by the native gatherers, that it was far from being so perfect an insulator as it has since become; moreover, the method of laying it on the conducting wire was so defective that every now and then air-holes or bubbles, so minute as to escape observation, occurred. The significance of this fact may not appear to the general reader who is not aware of the conditions on which alone a submarine electric cable can act. The wire or conductor along which the electric message flows, may be likened to a hollow pipe, the walls of which are composed of the insulating material which surrounds it; this insulating material is the gutta percha, and it can be easily understood that if this envelope is perforated by fine holes, the electric current, instead of passing from end to end of the cable, as it otherwise would, must escape and diffuse itself in the surrounding ocean, which is a good conductor.
These fine holes, or “leaks” as they are termed, may have let out but a very small portion of the strong current sent through the cable, but their number so enfeebled the life of the telegraph, that it only required a few more blunders of construction to have killed it before it was laid. These were not wanting, as we know by the evidence given in this matter before the committee of the House of Commons. Whilst the cable lay coiled in the tank at the manufactory, ready to be shipped, it had the misfortune to be exposed to the direct rays of the sun during three of the hottest days ever known in this country. The effect of this great heat was so to soften the gutta percha envelope of the wire, as to allow the latter to sink by its own gravity until it merely appeared on its under-surface, instead of maintaining its position in the centre of its axis; indeed, at some points, the wire actually showed through the thin gutta-percha, and where it so showed, it had to be cut out.
So much for the defective manipulation of the first Atlantic cable. But these were only initial errors. In the course of “paying out” it was subjected to all kinds of strains from the pitching of the vessel; at times it had to be cut and re-spliced whilst the ship was progressing; and after the first failure to deposit it in the ocean took place, and it was returned to a tank prepared to receive it at Keyham, it was cut about so mercilessly, and spliced again—or rather bungled together so carelessly,—that the wonder is, not that its insulation was thereby hopelessly impaired, but that the continuity of the conducting wire was maintained at all.
It is not, however, a matter of entire regret that this cable failed, inasmuch as from its method of construction, so far as the conducting wire was concerned, it is very doubtful whether it would have been such a success as to have satisfied the shareholders. The Atlantic telegraph, to pay, must be able to send a certain number of words per minute; otherwise the cost of transmission would be so enormous as to prevent its being generally used. Now, it is very questionable indeed if the old cable (even supposing its insulation to have been perfect) could have worked this paying number. Some of our most eminent electricians said, No. And for this feebleness of conduction there were two causes. In the first place, the wire, or wires, were very fine; and as it is a rule in conducting bodies that their swiftness of conductibility depends upon their diameters, or bulk, it must be evident that these small wires were a great mistake, inasmuch as they retarded the current. Another advantage of a large conductor is, that it is not much affected by “leakages” that would paralyse a small one. Independently, however, of the influence which size exerts in the conducting wire, is the question of quality. In the early days of electric telegraphy, nay, even so late as the time when the Atlantic Telegraph Cable was manufactured, it was not suspected that there was any difference in the conducting powers of different descriptions of copper. Since the great failure, however, this fact has been most conclusively established. The purer the copper, the greater its power of conduction, and between the coppers of commerce there is an enormous difference in this respect. The experience gained in laying cables since the failure of the Atlantic Cable has been very great. True, we do not find such vast stretches of ocean as the Atlantic to span every day, but cables have been laid in more difficult water and on a less advantageous ocean-bed with success. We have read dreadful descriptions, it is true, of a precipice in the bed of the sea off the west coast of Ireland; but the survey of the ground lately made by Captain Hoskin in Her Majesty’s ship Porcupine has dispelled this dismal statement. According to his careful soundings, the descent from the Irish bank to the bed of the ocean presents, at its steepest part, a dip of only 19 in 100—an incline which is represented in the following diagram:
Dip of 19 in 100.
Up such an ascent a locomotive may run with ease. The bottom is composed of a soft ooze, formed by the debris of the millions of organic beings which act as scavengers of the ocean, and then, their work being done, descend like fine dust to the bottom, sealing up, beyond power of being disturbed, any cable that may be deposited there.
It must be remembered that the average depth of the water covering the level terrace which runs between Valentia and the coast of Newfoundland is not more than two miles, a depth which is crossed by the cable from Toulon to Algiers, laid by Messrs. Glass and Elliot two years since, and now in perfect working order. Neither is there wanting experience in cables of great length. Let us instance that between Malta and Alexandria, which was laid by the same firm, and is but 500 miles shorter than the Atlantic Cable, the difficulties of laying which have been so exaggerated. It must be remembered that submarine telegraphy has arrived at a perfection which is almost marvellous, considering the little time that has elapsed since the first was laid—not more than eleven years since. From that period to the present time fifty-one lines of electric cables have been submerged, forty-four of which are at present in working order, and out of these Messrs. Glass and Elliot have laid no less than thirty. Indeed, so certain seems the success of a second attempt at depositing a working cable to this eminent house, that they have agreed to undertake the contract on the conditions of receiving their actual disbursements for labour and material, and a further profit of twenty per cent. on the actual cost of the line in the shares of the company, whilst they will make a cash subscription of 25,000l. in its ordinary capital. This certainly looks like business, and we hope the offer will be accepted. We understand that, towards the new capital of 600,000l., upwards of one-fourth has already been subscribed; and, as the faith of the public in the prospects of success in the undertaking is slowly but surely increasing, we may safely anticipate that, ere long, the whole sum will be made up.
It is not our province to enter into details of the monetary part of the scheme, but we cannot help stating that, if all the promises of returns held out should be fulfilled, there is yet to be reaped a splendid harvest from this field of enterprise. Thus ten words per minute—an estimate below that given by electricians—with the proposed heavy conducting wire, for sixteen hours a day, at a tariff of 2s. 6d. per word, would yield a revenue of 1200l. per day, or of 360,000l. a-year of 300 working days. This sum, together with government subsidies and other sources of income, will yield, we are told, a gross income of 438,000l.: a sum which it is estimated will not only pay working expenses and a handsome dividend to both old and new shareholders, but will yield a balance for a reserve fund, more than sufficient to lay a second cable in every two and-a-half years. Be this as it may, the advantages of connecting the new with the old world by such a line of communication are boundless to this country especially, whose possessions northward and southward of the United States, so constantly threatened, it would knit together and place within instant call of the mother country. At a moment when the value of our distant colonies is being questioned by grave professors at our seats of learning, this new instrument of civilisation appears upon the scene, destined, in all probability, to solve many of the difficulties in the way of government which of old the sundering ocean placed in our way. It is proposed to employ the Great Eastern to lay the new cable, and by this means to get rid of the dangers of laying it incident upon the pitching of a smaller vessel in bad weather. The Great Eastern, it is true, knows how to roll; but this motion is of little consequence compared with the fatal strain put upon a cable by the sudden lifting of the stern whilst great lengths of rope are being payed out in deep water. We see by the message of the President that he proposes to lend his countenance to the new scheme; we don’t know if this includes the loan of hard dollars or not, but we cannot conceive a scheme which may more legitimately appeal to government aid in the two countries than the Atlantic Telegraphic Cable. Our own government have already taken under their wing the cable now constructing to place our Eastern empire in communication with home; but surely the east is not more important than the west, and we should sail along the stream of events like a bird with but one wing, if we neglect to bridge the Atlantic Ocean. It would be a disgrace to us, who were the first to traverse the deep sea with the blue electric spark, big with the fate of nations, if we allowed news from the New World to come to us across the deserts of North America and Siberia and Russia, as it speedily will do, whilst we are hesitating about a paltry 2000 miles of ocean, where the cable once laid will never be disturbed. The pathway to the Yankees should not be allowed to pass the Czar’s doorway, or possibly he may refuse us a key at a moment when these loving friends may fraternise as they have done before in the hour of England’s difficulty.