heroes of the telegraph-第14章
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h he was a freshman but a few years before。
Thomson became a man of public note in connection with the laying of the first Atlantic cable。 After Cooke and Wheatstone had introduced their working telegraph in 1839； the idea of a submarine line across the Atlantic Ocean began to dawn on the minds of men as a possible triumph of the future。 Morse proclaimed his faith in it as early as the year 1840； and in 1842 he submerged a wire； insulated with tarred hemp and india…rubber； in the water of New York harbour； and telegraphed through it。 The following autumn Wheatstone performed a similar experiment in the Bay of Swansea。 A good insulator to cover the wire and prevent the electricity from 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 surveyor in the service of the East India Company。 Twenty years before he had seen whips made of it in Singapore； and believed that it would be useful in the fabrication of surgical apparatus。 Faraday and Wheatstone soon discovered its merits as an insulator； and in 1845 the latter suggested that it should be employed to cover the wire which it was proposed to lay from Dover to Calais。 It was tried on a wire laid across the Rhine between Deutz and Cologne。 In 1849 Mr。 C。 V。 Walker； electrician to the South Eastern Railway Company； submerged a wire coated with it； or； as it is technically called； a gutta…percha core； along the coast off Dover。
The following year Mr。 John Watkins Brett laid the first line across the Channel。 It was simply a copper wire coated with gutta…percha； without any other protection。 The core was payed out from a reel mounted behind the funnel of a steam tug； the Goliath； and sunk by means of lead weights attached to it every sixteenth of a mile。 She left Dover about ten o'clock on the morning of August 28； 1850； with some thirty men on board and a day's provisions。 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 anchor。 We gave them half an hour to convey the end of the wire to shore and attach the type… printing instrument； and then I sent the first electrical message across the Channel。 This was reserved for Louis Napoleon。' According to Mr。 F。 C。 Webb； however； the first of the signals were a mere jumble of letters； which were torn up。 He saved a specimen of the slip on which they were printed； and it was afterwards presented to the Duke of Wellington。
Next morning this pioneer line was broken down at a point about 200 Yards from Cape Grisnez； and it turned out that a Boulogne fisherman had raised it on his trawl and cut a piece away； thinking he had 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 experiment served to keep alive the concession； and the next year； on November 13； 1851； a protected core or true cable was laid from a Government hulk； the Blazer； which was towed across the Channel。
Next year Great Britain and Ireland were linked together。 In May； 1853； England was joined to Holland by a cable across the North Sea； from Orfordness to the Hague。 It was laid by the Monarch； a paddle 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 signals by jerking a needle instrument with a string。 These and other efforts in the Mediterranean and elsewhere were the harbingers of the memorable enterprise which bound the Old World and the New。
Bishop Mullock； head of the Roman Catholic Church in Newfoundland； was lying becalmed in his yacht one day in sight of Cape Breton Island； and began to dream of a plan for uniting his savage diocese to the 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 to him that the passage of news between America and Europe could thus be shortened by forty…eight hours。 On returning to St。 John's he published his idea in the COURIER by a letter dated November 8； 1850。
About the same time a similar plan occurred to Mr。 F。 N。 Gisborne； a telegraph engineer in Nova Scotia。 In the spring of 1851 he procured a grant from the Legislature of Newfoundland； resigned his situation in Nova Scotia； and having formed a company； began the construction of the land line。 But in 1853 his bills were dishonoured by the company； he was arrested for debt； 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 his library； and it flashed upon him that the telegraph to Newfoundland might be extended across the Atlantic Ocean。 The idea fired him with enthusiasm。 It seemed worthy of a man's ambition； and although he had retired from business to spend his days in peace； he resolved to dedicate his time； his energies； and fortune to the accomplishment of this grand enterprise。
A presentiment of success may have inspired him； but he was ignorant alike of submarine cables and the deep sea。 Was it possible to submerge the cable in the Atlantic； and would it be safe at the bottom？ Again； would the messages travel through the line fast enough to make it pay！ On the first question he consulted Lieutenant Maury； the great authority on mareography。 Maury told him that according to recent soundings by Lieutenant 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 minds。 As to the line itself； Mr。 Field consulted Professor Morse； who assured him that it was quite possible to make and lay a cable of that length。 He at once adopted the scheme of Gisborne as a preliminary step to the vaster undertaking； and promoted the New York； Newfoundland； and London Telegraph Company； to establish a line of telegraph between America and Europe。 Professor Morse was appointed electrician to the company。
The first thing to be done was to finish the line between St。 John's and Nova Scotia； and in 1855 an attempt was made to lay a cable across the Gulf of the St。 Lawrence； 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 steamboat was fitted out for the purpose； and the cable was submerged。 St。 John's was now connected with New York by a thousand miles of land and submarine telegraph。
Mr。 Field then directed his efforts to the completion of the trans… oceanic section。 He induced the American Government to despatch Lieutenant Berryman； in the Arctic； a
