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Heroes of the Telegraph

Chapter 4 SIR WILLIAM THOMSON.

Word Count: 10827    |    Released on: 28/11/2017

the son of a Scots-Irish farmer, showed a bent for scholarship when a boy, and became a pupil teacher in a small school near Ballynahinch, in County Down. With his summer earnings he educated himse

the University of Glasgow, where he achieved a reputa

sgow he was sent to the higher mathematical school of St. Peter's College, Cambridge. In 1845 he graduated as second wrangler, but won the Smith prize. This 'consolation stakes' is regarded as a better test of originality than the tripos. The first, or senior, wrangler probably

of seventeen, when ordinary lads are fond of games, and the cleverer sort are content to learn without attempting to originate, young Thomson had begun to make investigations. The CAMBRIDGE MATHEMATICAL JOURNAL of 1842 contains a paper by him-'On the uniform motion of heat in homogeneous solid bodies, and its connection with the mathematical theory of electricity.' In this he demonstrated the identity of the laws governing the distribution of electric or magnetic force in general, with the laws governing the distribution of the

osophy in the University of Glasgow. It was due to the brilliant promise he displayed, as much as to the influence of his father, that at the age of twenty-two he found him

m leaking into the water was requisite for the success of a long submarine line. India-rubber had been tried by Jacobi, the Russian electrician, as far back as 1811. He laid a wire insulated with rubber across the Neva at St. Petersburg, and succeeded in firing a mine by an electric spark sent through it; but india-rubber, although it is now used to a considerable extent, was not easy to manipulate in those days. Luckily another gum which could be melted by heat, and readily applied to the wire, made its appearance. Gutta-percha, the adhesive juice of the ISONANDRA GUTTA tree, was introduced to Europe in 1842 by Dr. Montgomerie, a Scotch su

ions. The route she was to follow was marked by a line of buoys and flags. By eight o'clock in the evening she arrived at Cape Grisnez, and came to anchor near the shore. Mr. Brett watched the operations through a glass at Dover. 'The declining sun,' he says, 'enabled me to discern the moving shadow of the steamer's smoke on the white cliff; thus indicating her progress. At length the shadow ceased to move. The vessel had evidently come to an a

ad found a rare species of tangle with gold in its heart. This misfortune suggested the propriety of arming the core against mechanical injury by sheathing it in a cable of hemp and iron wires. The e

e steamer which had been fitted for the work. During the night she met with such heavy weather that the engineer was lashed near the brakes; and the electrician, Mr. Latimer Clark, sent the continuity

mainland by a line of telegraph through the forest from St. John's to Cape Ray, and cables across the mouth of the St. Lawrence from Cape Ray to Nova Scotia. St. John's was an Atlantic port, and it seemed

ebt, and stripped of all his fortune. The following year, however, he was introduced to Mr. Cyrus Field, of New York, a wealthy merchant, who had just returned from a six months' tour in South America. Mr. Field invited Mr. Gisborne to his house in order to discuss the project. When his visitor was gone, Mr. Field began to turn over a terrestrial globe which stood in

enant Berryman, of the United States brig Dolphin, the bottom between Ireland and Newfoundland was a plateau covered with microscopic shells at a depth not over 2000 fathoms, and seemed to have been made for the very purpose of receiving the cable. He left the question of finding a time calm enough, the sea smooth enough, a wire long enough, and a ship big enough,' to lay a line some sixteen hundred miles in length to other m

nce, It was payed out from a barque in tow of a steamer; but when half was laid a gale rose, and to keep the barque from sinking the line was cut away. Next summer a

Arctic, and the British Admiralty to send Lieutenant: Dayman, in the Cyclops, to make a special survey along the proposed route of the cable. These soundings

as fitting that the work should be international, and that the British people should be asked to contribute towards the manufacture and submersion of the cable. Mr. Field therefore proceeded to London, and with the as

y on the lengthy cable between England and the Hague. Faraday showed that it was caused by induction between the electricity in the wire and the earth or water surrounding it. A core, in fact, is an attenuated Leyden jar; the wire of the core, its insulating jacket, and the soil or water around it stand respectively for the inner tinfoil, the glass, and the outer tinfoil of the jar. When the wire is charged from a battery, the electricity induces an opposite charge in the water as it travels along, and as the two charges attract each other, the exciting charge is restrained. The speed of a signal through the conductor of a submarine cable is thus diminished by a drag of its own making. The nature of the phenomenon was clear, but the laws which governed it were still a mystery. It became a serious question whether, on a lo

hat he was a man to enlist in their adventure. It is not enough to say the young Glasgow professor threw himself heart and soul into their work. He descended in their midst like the very genius of electricity, and helped them out of all their difficulties. In 1857 he published in the ENGINEER the who

n the core of a cable during its manufacture and submersion. Moreover, it proved the best apparatus for receiving the messages through a long cable. The Morse and other instruments, however suitable for land lines and short cables, were all but useless on the Atlantic line, owing to the retardat

, and wound with tarred hemp, over which a sheath of eighteen strands, each of seven iron wires, was laid in a close spiral. It weighed nearly a ton to the mile, was flexib

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 t

d 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 excellen

lance 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 muffled step,

ther. 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-beat

was only making four. To check this waste of cable the engineer tightened the brakes; but as the stern

htning through all the ships, and pr

d 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,

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

dezvous; 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 infl

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 becam

al 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. M

a grand salute of 100 guns resounded in New York, the streets were decorated w

r innumerable sermons and a prodigious quantity

the angry

s stand no

d hands the

ngs of each

d the cable

irdle roun

e nations '

brothers o

pledging,

for the wo

rce over

age, and

tion, 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 gener

REE HUNDRED AND TWELVE CELLS!] The reaction at this news was tremendous. Some writers even hinted that the line was a mere hoax, and others pronounced it a stock exchange speculation. Sensible men doubted whether the cable had ever 'spoken;' but in addition to the royal despatch, items of dail

rts to revive the company were futile. It was not until 1864 that with the assistance of Mr. Thomas (afterwards Lord) Brassey, and Mr. (now Sir) John Fender, that he succeeded in raising the neces

s 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

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

ern left the Nore for Foilhommerum Bay, Valentia I

at 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 3

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 priv

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

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 shore end was landed during the day by the Medway;

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 t

bably 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

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 intelligibl

e 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 pre

ain 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 un

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

ficulty 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 travell

l 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 glass silvered, the magnets of hair-spring, and both t

ntally 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

hion, and 'deaden' the movements of the mirror. The needle is thus prevented from idly swinging abo

'speaker' before it is sent into the ground, and the wandering light spot on the screen faithfully represent

lpable 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 cab

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

r 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 e

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 passes through this coil, so suspended in the highly magnetic space between th

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,

nwards to the writing-tablet. The only avenue of escape for it is by the fine glass siphon, and through this it rushes accordingly and discharges itself in a rain upon the paper. The natural repulsion between its like electrified particles

its somewhat epigrammatic title 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 origina

called 'dots' and 'dashes,' from the fact that the Morse recorder actually marks the message in long and short lines, or dots and dashes. In the siphon recorder script dots and dashes are represented by curves of opposite fl

y words or more per minute can be transmitted by an automatic sender, and the recorder has been found on land lines and short cables to write off the message at this incredible speed. When we consider that every word is, on the average, composed of fifteen separate waves, we m

to all the long cables of that most enterprising of telegraph companies-the Eastern-so that both stations may 'speak' to each other simultaneously. Thus the carrying

s activity depends on the galvanic current. From three separate sources invisible currents are led to its principal parts, and are at once physically changed. That entering the mouse-mill becomes transmuted in part into the mechanical motion of the revolving drum, and part into electricity of

ine marking of the siphon that the ink should neither be too strongly nor too feebly electrified. When the atmosphere is moderately humid, a proper supply of electricity is generated by the mouse-mill, the paper is sufficiently moist, and the ink flows freely. But an excess of moisture in the air diminishes the available supply of EXALTED electricity. In fact, the damp depositing on the parts leads the electricity away, and the in

ising round the instrument, saturating the air and paper. At more temperate places the ordinary means of drying the air by taking advantage of the absorbing power of sulphuric acid for moisture prevailed. At Marseilles the recorder acted in some respects like a barometer. Marseilles is subject to sudden incursions of dry northerly winds, termed the MISTRAL. The recorder never failed to indicate the

completion of submarine communication between London and Bombay by the successful laying of the Falmouth, Gibraltar and Malta and the British Indian cable lines.' Mr. Pender's house was literally turned outside in; the front door was removed, the courtyard temporarily covered with an iron roof and the whole decorated in the grandest style. Over the gateway was a gallery filled with the band of the Scots Fusilier Guards; and over the portico of the house door hung the grapnel which brought up the 1865 cable, made resplendent to the eye by a coating of gold leaf. A handsome staircase, newly erected, permitted the guests to pass from the rec

f steel have been substituted for the electro-magnets which influence the swinging coil; and the ink, inst

irst applied condensers to sharpen the signals, and Professor Fleeming Jenkin, of Edinburgh University. In conjunction with the latter, he also

by a single current, whether positive or negative. Moreover, to curb the prolongation of the signals due to induction, each signal was made by two opposite currents in succession-a positive followed by a negative, or a n

the laying of the Para to Pernambuco section of the Brazilian coast cables in 1873, and introduced his method of deep-sea sounding, in which a steel pianoforte wire replaces the ordinary land line.

portant aid to the mariner is, however, the adjustable compass, which he brought out soon afterwards. It is a great improvement on the older instrument,

relating to the sea perhaps arose, or at any rate was fostered, by his experiences on the Agamemnon and the Great Eastern. Babbage was among the first to suggest that a lighthouse might be made to signal a distinctive number by

for measuring electricity. As early as 1845 his mind was attracted to this subject. He pointed ou

r and since then he has introduced a chain or series of beautiful and effective instruments, including the quadrant electrometer, which cover the entire field of electrostatic

thematical for the general reader. His varied services have been acknowledged by numerous distinctions, including the highest honour

in the non-scientific world, that the scientific world believes Science has discovered ways of explaining all the facts of Nature without adopting any definite belief in a Creator. I have never doubted that that impression was utterly groundless. It seems to me that when a scientific man says-as it has been said fro

oving that there is something beyond that mass of dead matter of which he is thinking. His very thought is in itself a contradiction to the idea that there is nothing in existence but dead matter. Science can do little positively towar

ture for certain-it will be unlike the past. Everything is in a state of evolution and progress. The science of dead matter, which has been the principal subject of my thoughts during my life, is, I may say, strenuous on this point, that THE AGE OF THE EARTH IS DEFINITE. We do not say whether it is twenty million years or more, or less, but me say it is NOT INDEFINITE. And we can say very definitely that it is not an inconceivably great number of millions of years. Here, then, we are brought face to face with the most wonderful of all miracles, the commencement of life on this earth. This earth, certainly a moderate number of millions of year

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