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The British Government promised Mr. Field a subsidy of L1,400 a year, and the loan of ships to lay the cable. He solicited an equal help from Congress, but a large number of the senators, actuated by a national jealousy of England, and looking to the fact that both ends of the line were to lie in British territory, opposed the grant. It appeared to these far-sighted politicians that England, the hereditary foe, was 'literally crawling under the sea to get some advantage over the United States.' The Bill was only pa.s.sed by a majority of a single vote. In the House of Representatives it encountered a similar hostility, but was ultimately signed by President Pierce.
The Agamemnon, a British man-of-war fitted out for the purpose, took in the section made at Greenwich, and the Niagara, an American warship, that made at Liverpool. The vessels and their consorts met in the bay of Valentia Island, on the south-west coast of Ireland, where on August 5, 1857, the sh.o.r.e end of the cable was landed from the Niagara. It was a memorable scene. The ships in the bay were dressed in bunting, and the Lord Lieutenant of Ireland stood on the beach, attended by his following, to receive the end from the American sailors. Visitors in holiday attire collected in groups to watch the operations, and eagerly joined with his excellency in helping to pull the wire ash.o.r.e. When it was landed, the Reverend Mr. Day, of Kenmore, offered up a prayer, asking the Almighty to prosper the undertaking, Next day the expedition sailed; but ere the Niagara had proceeded five miles on her way the sh.o.r.e-end parted, and the repairing of it delayed the start for another day.
At first the Niagara went slowly ahead to avoid a mishap, but as the cable ran out easily she increased her speed. The night fell, but hardly a soul slept. The utmost vigilance was maintained throughout the vessel.
Apart from the noise of the paying-out machinery, there was an awful stillness on board. Men walked about with a m.u.f.fled step, or spoke in whispers, as if they were afraid the sound of their voices would break the slender line. It seemed as though a great and valued friend lay at the point of death.
The submarine hill, with its dangerous slope, was pa.s.sed in safety, and the 'telegraph plateau,' nearly two miles deep, was reached, when suddenly the signals from Ireland, which told that the conductor was intact, stopped altogether. Professor Morse and De Sauty, the electricians, failed to restore the communication, and the engineers were preparing to cut the cable, when quite as suddenly the signals returned, and every face grew bright. A weather-beaten old sailor said, 'I have watched nearly every mile of it as it came over the side, and I would have given fifty dollars, poor man as I am, to have saved it, although I don't expect to make anything by it when it is laid down.'
But the joy was short-lived. The line was running out at the rate of six miles an hour, while the vessel was only making four. To check this waste of cable the engineer tightened the brakes; but as the stern of the ship rose on the swell, the cable parted under the heavy strain, and the end was lost in the sea.
The bad news ran like a flash of lightning through all the ships, and produced a feeling of sorrow and dismay.
No attempt was made to grapple the line in such deep water, and the expedition returned to England. It was too late to try again that year, but the following summer the Agamemnon and Niagara, after an experimental trip to the Bay of Biscay, sailed from Plymouth on June 10 with a full supply of cable, better gear than before, and a riper experience of the work. They were to meet in the middle of the Atlantic, where the two halves of the cable on board of each were to be spliced together, and while the Agamemnon payed out eastwards to Valentia Island the Niagara was to pay out westward to Newfoundland. On her way to the rendezvous the Agamemnon encountered a terrific gale, which lasted for a week, and nearly proved her destruction.
On Sat.u.r.day, the 26th, the middle splice was effected and the bight dropped into the deep. The two ships got under weigh, but had not proceeded three miles when the cable broke in the paying-out machinery of the Niagara. Another splice, followed by a fresh start, was made during the same afternoon; but when some fifty miles were payed out of each vessel, the current which kept up communication between them suddenly failed owing to the cable having snapped in the sea. Once more the middle splice was made and lowered, and the ships parted company a third time. For a day or two all went well; over two hundred miles of cable ran smoothly out of each vessel, and the anxious chiefs began to indulge in hopes of ultimate success, when the cable broke about twenty feet behind the stern of the Agamemnon.
The expedition returned to Queenstown, and a consultation took place.
Mr. Field, and Professor Thomson, who was on board the Agamemnon, were in favour of another trial, and it was decided to make one without delay. The vessels left the Cove of Cork on July 17; but on this occasion there was no public enthusiasm, and even those on board felt as if they were going on another wild goose chase. The Agamemnon was now almost becalmed on her way to the rendezvous; but the middle splice was finished by 12.30 p.m. on July 29, 1858, and immediately dropped into the sea. The ships thereupon started, and increased their distance, while the cable ran easily out of them. Some alarm was caused by the stoppage of the continuity signals, but after a time they reappeared.
The Niagara deviated from the great arc of a circle on which the cable was to be laid, and the error was traced to the iron of the cable influencing her compa.s.s. Hence the Gorgon, one of her consorts, was ordered to go ahead and lead the way. The Niagara pa.s.sed several icebergs, but none injured the cable, and on August 4 she arrived in Trinity Bay, Newfoundland. At 6. a.m. next morning the sh.o.r.e end was landed into the telegraph-house which had been built for its reception.
Captain Hudson, of the Niagara, then read prayers, and at one p.m.
H.M.S. Gorgon fired a salute of twenty-one guns.
The Agamemnon made an equally successful run. About six o'clock on the first evening a huge whale was seen approaching on the starboard bow, and as he sported in the waves, rolling and lashing them into foam, the onlookers began to fear that he might endanger the line. Their excitement became intense as the monster heaved astern, nearer and nearer to the cable, until his body grazed it where it sank into the water; but happily no harm was done. Damaged portions of the cable had to be removed in paying-out, and the stoppage of the continuity signals raised other alarms on board. Strong head winds kept the Agamemnon back, and two American ships which got into her course had to be warned off by firing guns. The signals from the Niagara became very weak, but on Professor Thomson asking the electricians on board of her to increase their battery power, they improved at once. At length, on Thursday, August, 5, the Agamemnon, with her consort, the Valorous, arrived at Valentia Island, and the sh.o.r.e end was landed into the cable-house at Knightstown by 3 p.m., and a royal salute announced the completion of the work.
The news was received at first with some incredulity, but on being confirmed it caused a universal joy. On August 16 Queen Victoria sent a telegram of congratulation to President Buchanan through the line, and expressed a hope that it would prove 'an additional link between the nations whose friendship is founded on their common interest and reciprocal esteem.' The President responded that, 'it is a triumph more glorious, because far more useful to mankind, than was ever won by conqueror on the field of battle. May the Atlantic telegraph, under the blessing of heaven, prove to be a bond of perpetual peace and friendship between the kindred nations, and an instrument destined by Divine Providence to diffuse religion, civilisation, liberty, and law throughout the world.'
These messages were the signal for a fresh outburst of enthusiasm. Next morning a grand salute of 100 guns resounded in New York, the streets were decorated with flags, the bells of the churches rung, and at night the city was illuminated.
The Atlantic cable was a theme of inspiration for innumerable sermons and a prodigious quant.i.ty of doggerel. Among the happier lines were these:--
''Tis done! the angry sea consents, The nations stand no more apart; With clasped hands the continents Feel throbbings of each other's heart.
Speed! speed the cable! let it run A loving girdle round the earth, Till all the nations 'neath the sun Shall be as brothers of one hearth.
As brothers pledging, hand in hand, One freedom for the world abroad, One commerce over every land, One language, and one G.o.d.'
The rejoicing reached a climax in September, when a public service was held in Trinity Church, and Mr. Field, the hero of the hour, as head and mainspring of the expedition, received an ovation in the Crystal Palace at New York. The mayor presented him with a golden casket as a souvenir of 'the grandest enterprise of our day and generation.' The band played 'G.o.d save the Queen,' and the whole audience rose to their feet. In the evening there was a magnificent torchlight procession of the city firemen.
That very day the cable breathed its last. Its insulation had been failing for some days, and the only signals which could be read were those given by the mirror galvanometer.[It is said to have broken down while Newfoundland was vainly attempting to inform Valentia that it was sending with THREE HUNDRED AND TWELVE CELLS!] The reaction at this news was tremendous. Some writers even hinted that the line was a mere hoax, and others p.r.o.nounced it a stock exchange speculation. Sensible men doubted whether the cable had ever 'spoken;' but in addition to the royal despatch, items of daily news had pa.s.sed through the wire; for instance, the announcement of a collision between two ships, the Arabia and the Europa, off Cape Race, Newfoundland, and an order from London, countermanding the departure of a regiment in Canada for the seat of the Indian Mutiny, which had come to an end.
Mr. Field was by no means daunted at the failure. He was even more eager to renew the work, since he had come so near to success. But the public had lost confidence in the scheme, and all his efforts to revive the company were futile. It was not until 1864 that with the a.s.sistance of Mr. Thomas (afterwards Lord) Bra.s.sey, and Mr. (now Sir) John Fender, that he succeeded in raising the necessary capital. The Gla.s.s, Elliot, and Gutta-Percha Companies were united to form the well-known Telegraph Construction and Maintenance Company, which undertook to manufacture and lay the new cable.
Much experience had been gained in the meanwhile. Long cables had been submerged in the Mediterranean and the Red Sea. The Board of Trade in 1859 had appointed a committee of experts, including Professor Wheatstone, to investigate the whole subject, and the results were published in a Blue-book. Profiting by these aids, an improved type of cable was designed. The core consisted of a strand of seven very pure copper wires weighing 300 lbs. a knot, coated with Chatterton's compound, which is impervious to water, then covered with four layers of gutta-percha alternating with four thin layers of the compound cementing the whole, and bringing the weight of the insulator to 400 lbs. per knot. This core was served with hemp saturated in a preservative solution, and on the hemp as a padding were spirally wound eighteen single wires of soft steel, each covered with fine strands of Manilla yam steeped in the preservative. The weight of the new cable was 35.75 cwt. per knot, or nearly twice the weight of the old, and it was stronger in proportion.
Ten years before, Mr. Marc Isambard Brunel, the architect of the Great Eastern, had taken Mr. Field to Blackwall, where the leviathan was lying, and said to him, 'There is the ship to lay the Atlantic cable.'
She was now purchased to fulfil the mission. Her immense hull was fitted with three iron tanks for the reception of 2,300 miles of cable, and her decks furnished with the paying-out gear. Captain (now Sir) James Anderson, of the Cunard steamer China, a thorough seaman, was appointed to the command, with Captain Moriarty, R.N., as chief navigating officer. Mr. (afterwards Sir) Samuel Canning was engineer for the contractors, the Telegraph Construction and Maintenance Company, and Mr.
de Sauty their electrician; Professor Thomson and Mr. Cromwell Fleetwood Varley were the electricians for the Atlantic Telegraph Company. The Press was ably represented by Dr. W. H. Russell, correspondent of the TIMES. The Great Eastern took on board seven or eight thousand tons of coal to feed her fires, a prodigious quant.i.ty of stores, and a mult.i.tude of live stock which turned her decks into a farmyard. Her crew all told numbered 500 men.
At noon on Sat.u.r.day, July 15, 1865, the Great Eastern left the Nore for Foilhommerum Bay, Valentia Island, where the sh.o.r.e end was laid by the Caroline.
At 5.30 p.m. on Sunday, July 23, amidst the firing of cannon and the cheers of the telegraph fleet, she started on her voyage at a speed of about four knots an hour. The weather was fine, and all went well until next morning early, when the boom of a gun signalled that a fault had broken out in the cable. It turned out that a splinter of iron wire had penetrated the core. More faults of the kind were discovered, and as they always happened in the same watch, there was a suspicion of foul play. In repairing one of these on July 31, after 1,062 miles had been payed out, the cable snapped near the stern of the ship, and the end was lost. 'All is over,' quietly observed Mr. Canning; and though spirited attempts were made to grapple the sunken line in two miles of water, they failed to recover it.
The Great Eastern steamed back to England, where the indomitable Mr.
Field issued another prospectus, and formed the Anglo-American Telegraph Company, with a capital of L600,000, to lay a new cable and complete the broken one. On July 7, 1866, the William Cory laid the sh.o.r.e end at Valentia, and on Friday, July 13, about 3 p.m., the Great Eastern started paying-out once more. [Friday is regarded as an unlucky, and Sunday as a lucky day by sailors. The Great Eastern started on Sunday before and failed; she succeeded now. Columbus sailed on a Friday, and discovered America on a Friday.] A private service of prayer was held at Valentia by invitation of two directors of the company, but otherwise there was no celebration of the event. Professor Thomson was on board; but Dr. W. H. Russell had gone to the seat of the Austro-Prussian war, from which telegrams were received through the cable.
The 'big ship' was attended by three consorts, the Terrible, to act as a spy on the starboard how, and warn other vessels off the course, the Medway on the port, and the Albany on the starboard quarter, to drop or pick up buoys, and make themselves generally useful. Despite the fickleness of the weather, and a 'foul flake,' or clogging of the line as it ran out of the tank, there was no interruption of the work. The 'old coffee mill,' as the sailors dubbed the paying-out gear, kept grinding away. 'I believe we shall do it this time, Jack,' said one of the crew to his mate.
On the evening of Friday, July 27, the expedition made the entrance of Trinity Bay, Newfoundland, in a thick fog, and next morning the Great Eastern cast her anchor at Heart's Content. Flags were flying from the little church and the telegraph station on sh.o.r.e. The Great Eastern was dressed, three cheers were given, and a salute was fired. At 9 a.m. a message from England cited these words from a leading article in the current TIMES: 'It is a great work, a glory to our age and nation, and the men who have achieved it deserve to be honoured among the benefactors of their race.' 'Treaty of peace signed between Prussia and Austria.' The sh.o.r.e end was landed during the day by the Medway; and Captain Anderson, with the officers of the telegraph fleet, went in a body to the church to return thanks for the success of the expedition.
Congratulations poured in, and friendly telegrams were again exchanged between Her Majesty and the United States. The great work had been finally accomplished, and the two worlds were lastingly united.
On August 9 the Great Eastern put to sea again in order to grapple the lost cable of 1865, and complete it to Newfoundland. Arriving in mid-ocean she proceeded to fish for the submerged line in two thousand fathoms of water, and after repeated failures, involving thirty casts of the grapnel, she hooked and raised it to surface, then spliced it to the fresh cable in her hold, and payed out to Heart's Content, where she arrived on Sat.u.r.day, September 7. There were now two fibres of intelligence between the two hemispheres.
On his return home, Professor Thomson was among those who received the honour of knighthood for their services in connection with the enterprise. He deserved it. By his theory and apparatus he probably did more than any other man, with the exception of Mr. Field, to further the Atlantic telegraph. We owe it to his admirable inventions, the mirror instrument of 1857 and the siphon recorder of 1869, that messages through long cables are so cheap and fast, and, as a consequence, that ocean telegraphy is now so common. Hence some account of these two instruments will not be out of place.
Sir William Thomson's siphon recorder, in all its present completeness, must take rank as a masterpiece of invention. As used in the recording or writing in permanent characters of the messages sent through long submarine cables, it is the acknowledged chief of 'receiving instruments,' as those apparatus are called which interpret the electrical condition of the telegraph wire into intelligible signals.
Like other mechanical creations, no doubt its growth in idea and translation into material fact was a step-by-step process of evolution, culminating at last in its great fitness and beauty.
The marvellous development of telegraphy within the last generation has called into existence a great variety of receiving instruments, each admirable in its way. The Hughes, or the Stock Exchange instruments, for instance, print the message in Roman characters; the sounders strike it out on stops or bells of different tone; the needle instruments indicate it by oscillations of their needles; the Morse daubs it in ink on paper, or embosses it by a hard style; while Bain's electro-chemical receiver stains it on chemically prepared paper. The Meyer-Baudot and the Quadruple receive four messages at once and record them separately; while the harmonic telegraph of Elisha Gray can receive as many as eight simultaneously, by means of notes excited by the current in eight separate tuning forks.
But all these instruments have one great drawback for delicate work, and, however suitable they may be for land lines, they are next to useless for long cables. They require a certain definite strength of current to work them, whatever it may be, and in general it is very considerable. Most of the moving parts of the mechanism are comparatively heavy, and unless the current is of the proper strength to move them, the instrument is dumb, while in Bain's the solution requires a certain power of current to decompose it and leave the stain.
In overland lines the current traverses the wire suddenly, like a bullet, and at its full strength, so that if the current be sufficiently strong these instruments will be worked at once, and no time will be lost. But it is quite different on submarine cables. There the current is slow and varying. It travels along the copper wire in the form of a wave or undulation, and is received feebly at first, then gradually rising to its maximum strength, and finally dying away again as slowly as it rose. In the French Atlantic cable no current can be detected by the most delicate galvanoscope at America for the first tenth of a second after it has been put on at Brest; and it takes about half a second for the received current to reach its maximum value. This is owing to the phenomenon of induction, very important in submarine cables, but almost entirely absent in land lines. In submarine cables, as is well known, the copper wire which conveys the current is insulated from the sea-water by an envelope, usually of gutta-percha. Now the electricity sent into this wire INDUCES electricity of an opposite kind to itself in the sea-water outside, and the attraction set up between these two kinds 'holds back' the current in the wire, and r.e.t.a.r.ds its pa.s.sage to the receiving station.
It follows, that with a receiving instrument set to indicate a particular strength of current, the rate of signalling would be very slow on long cables compared to land lines; and that a different form of instrument is required for cable work. This fact stood greatly in the way of early cable enterprise. Sir William (then Professor) Thomson first solved the difficulty by his invention of the 'mirror galvanometer,' and rendered at the same time the first Atlantic cable company a commercial success. The merit of this receiving instrument is, that it indicates with extreme sensibility all the variations of the current in the cable, so that, instead of having to wait until each signal wave sent into the cable has travelled to the receiving end before sending another, a series of waves may be sent after each other in rapid succession. These waves, encroaching upon each other, will coalesce at their bases; but if the crests remain separate, the delicate decipherer at the other end will take cognisance of them and make them known to the eye as the distinct signals of the message.
The mirror galvanometer is at once beautifully simple and exquisitely scientific. It consists of a very long fine coil of silk-covered copper wire, and in the heart of the coil, within a little air-chamber, a small round mirror, having four tiny magnets cemented to its back, is hung, by a single fibre of floss silk no thicker than a spider's line. The mirror is of film gla.s.s silvered, the magnets of hair-spring, and both together sometimes weigh only one-tenth of a grain. A beam of light is thrown from a lamp upon the mirror, and reflected by it upon a white screen or scale a few feet distant, where it forms a bright spot of light.
When there is no current on the instrument, the spot of light remains stationary at the zero position on the screen; but the instant a current traverses the long wire of the coil, the suspended magnets twist themselves horizontally out of their former position, the mirror is of course inclined with them, and the beam of light is deflected along the screen to one side or the other, according to the nature of the current.
If a POSITIVE current--that is to say, a current from the copper pole of the battery--gives a deflection to the RIGHT of zero, a NEGATIVE current, or a current from the zinc pole of the battery, will give a deflection to the left of zero, and VICE VERSA.
The air in the little chamber surrounding the mirror is compressed at will, so as to act like a cushion, and 'deaden' the movements of the mirror. The needle is thus prevented from idly swinging about at each deflection, and the separate signals are rendered abrupt and 'dead beat,' as it is called.
At a receiving station the current coming in from the cable has simply to be pa.s.sed through the coil of the 'speaker' before it is sent into the ground, and the wandering light spot on the screen faithfully represents all its variations to the clerk, who, looking on, interprets these, and cries out the message word by word.
The small weight of the mirror and magnets which form the moving part of this instrument, and the range to which the minute motions of the mirror can be magnified on the screen by the reflected beam of light, which acts as a long impalpable hand or pointer, render the mirror galvanometer marvellously sensitive to the current, especially when compared with other forms of receiving instruments. Messages have been sent from England to America through one Atlantic cable and back again to England through another, and there received on the mirror galvanometer, the electric current used being that from a toy battery made out of a lady's silver thimble, a grain of zinc, and a drop of acidulated water.
The practical advantage of this extreme delicacy is, that the signal waves of the current may follow each other so closely as almost entirely to coalesce, leaving only a very slight rise and fall of their crests, like ripples on the surface of a flowing stream, and yet the light spot will respond to each. The main flow of the current will of course shift the zero of the spot, but over and above this change of place the spot will follow the momentary fluctuations of the current which form the individual signals of the message. What with this shifting of the zero and the very slight rise and fall in the current produced by rapid signalling, the ordinary land line instruments are quite unserviceable for work upon long cables.
The mirror instrument has this drawback, however--it does not 'record'
the message. There is a great practical advantage in a receiving instrument which records its messages; errors are avoided and time saved. It was to supply such a desideratum for cable work that Sir William Thomson invented the siphon recorder, his second important contribution to the province of practical telegraphy. He aimed at giving a GRAPHIC representation of the varying strength of the current, just as the mirror galvanometer gives a visual one. The difficulty of producing such a recorder was, as he himself says, due to a difficulty in obtaining marks from a very light body in rapid motion, without impeding that motion. The moving body must be quite free to follow the undulations of the current, and at the same time must record its motions by some indelible mark. As early as 1859, Sir William sent out to the Red Sea cable a piece of apparatus with this intent. The marker consisted of a light platinum wire, constantly emitting sparks from a Rhumkorff coil, so as to perforate a line on a strip of moving paper; and it was so connected to the movable needle of a species of galvanometer as to imitate the motions of the needle. But before it reached the Red Sea the cable had broken down, and the instrument was returned dismantled, to be superseded at length by the siphon recorder, in which the marking point is a fine gla.s.s siphon emitting ink, and the moving body a light coil of wire hung between the poles of a magnet.
The principle of the siphon recorder is exactly the inverse of the mirror galvanometer. In the latter we have a small magnet suspended in the centre of a large coil of wire--the wire enclosing the magnet, which is free to rotate round its own axis. In the former we have a small coil suspended between the poles of a large magnet--the magnet enclosing the coil, which is also free to rotate round its own axis. When a current pa.s.ses through this coil, so suspended in the highly magnetic s.p.a.ce between the poles of the magnet, the coil itself experiences a mechanical force, causing it to take up a particular position, which varies with the nature of the current, and the siphon which is attached to it faithfully figures its motion on the running paper.
The point of the siphon does not touch the paper, although it is very close. It would impede the motion of the coil if it did. But the 'capillary attraction' of so fine a tube will not permit the ink to flow freely of itself, so the inventor, true to his instincts, again called in the aid of electricity, and electrified the ink. The siphon and reservoir are together supported by an EBONITE bracket, separate from the rest of the instrument, and INSULATED from it; that is to say, electricity cannot escape from them to the instrument. The ink may, therefore, be electrified to an exalted state, or high POTENTIAL as it is called, while the body of the instrument, including the paper and metal writing-tablet, are in connection with the earth, and at low potential, or none at all, for the potential of the earth is in general taken as zero.
The ink, for example, is like a highly-charged thunder-cloud supported over the earth's surface. Now the tendency of a charged body is to move from a place of higher to a place of lower potential, and consequently the ink tends to flow downwards to the writing-tablet. The only avenue of escape for it is by the fine gla.s.s siphon, and through this it rushes accordingly and discharges itself in a rain upon the paper. The natural repulsion between its like electrified particles causes the shower to issue in spray. As the paper moves over the pulleys a delicate hair line is marked, straight when the siphon is stationary, but curved when the siphon is pulled from side to side by the oscillations of the signal coil.
It is to the mouse-mill that me must look both for the electricity which is used to electrify the ink and for the motive power which drives the paper. This unique and interesting little motor owes its somewhat epigrammatic t.i.tle to the resemblance of the drum to one of those sparred wheels turned by white mice, and to the amusing fact of its capacity for performing work having been originally computed in terms of a 'mouse-power.' The mill is turned by a stream of electricity flowing from the battery above described, and is, in fact, an electro-magnetic engine worked by the current.