Back Aa

Story of the Atlantic Cable

Close

<h3>CHAPTER XIII EXPERIENCE, INVESTIGATION, AND PROGRESS</h3> <div class="blockquot">The Red Sea Line—Government Inquiry—Electrical Standards and Units—Further Cables—Improvements in Manufacture, Testing, and Working—Completion of Pioneer Stage. </div> The Red Sea Line.—Mr. Lionel Gisborne had obtained powers from the Turkish Government to carry a telegraph-line across Egypt and lay a cable down the Red Sea. The importance of this line to Great Britain led the Government to give definite assistance. The first portion of the proposed cable—from Suez to Aden, with intermediate landings—was laid in 1859. The different sections broke down one by one. They were all laid very taut, the slack in some cases being less than one per cent, though the bottom was in certain parts very uneven. The second portion of the line, from Aden to Kurrachee, with intermediate stations, was laid during 1860, the slack working out at 0.1 per cent only. Faults developed very quickly in all the sections of both portions of the line. Apart from the small allowance for slack, the type of cable{170} adopted was of far too fragile a nature for some of its rough, reef-like resting-spots; indeed, the undertaking was spoken of as “like running a donkey for the Leger”! The promoters of this enterprise, having neither specially qualified men nor the necessary materials for carrying out repairs, were obliged to abandon it before any commercial work had been effected. This was a most unfortunate line in every way, for a complete message was never got through the entire length, but only through each section separately. Nevertheless, until quite recently, it cost Great Britain £36,000 per annum. Inquiry on the Construction of Submarine Telegraphs.—Aroused more especially by the above failure, the Government, in 1859, before undertaking further responsibility, resolved to thoroughly investigate the construction of cables. It was also felt that the ultimate failure of the Atlantic line was possibly due, in part, to weak joints and general defects in the manufacture of the insulating envelope. This committee—under the direction of the Board of Trade, with Captain, afterward Sir Douglas, Galton, R.E., in the chair—devoted twenty-two sittings (covering a considerable period of time) to questioning engineers, electricians, professors, physicists, manufacturers, and seamen, who had taken part in the various branches of cable-work and whose knowledge or experience might throw light on the subject. Investigations were instituted concerning the structure of all cables previously made, and the quality of the different materials used, as to special points arising during manufacture and laying, on the routes taken, electrical testing, and{171} on sending and receiving instruments, speed of signaling, etc. Actual experiments were also made in connection with this inquiry, to ascertain (1) the electrical and mechanical qualities of copper, pure and alloyed; also of gutta-percha and other insulating substances; (2) the chemical change in their condition when submerged; (3) the effects of temperature and pressure on the insulating substances employed; (4) the elongation and breaking strain of copper wires; of iron, steel, and tarred hemp separately and combined; (5) the phenomena connected with electrically charging and discharging conductors; (6) methods of testing conductors and of locating faults; besides the whole science and practise of cable-making and laying. The report of the committee was not published till some time afterward. It expressed a conviction that submarine telegraphy might be made sure and remunerative in the future, based on the evidence adduced regarding the proper manufacture and working of submarine telegraphs. Formulation of Electrical Standards and Units.—This inquiry was shortly followed by an important paper before the British Association for the advancement of science by Sir Charles Bright and Mr. Latimer Clark (then in partnership), which put the practise of electrical testing on a systematic basis, thereby considerably forwarding all electrical work connected with submarine telegraphy. A committee was formed shortly afterward, which gave the suggestions then brought forward the seal of universal officialdom. Further Cables.—About this time a number of other cable enterprises were set afoot, some in{172} shallow water and others in comparatively great depths. Though few of them were able to benefit by the information obtained in the inquiry, they were, in the main, more or less successful. These projects included cables between Malta and Alexandria, besides others in the Mediterranean and elsewhere. Sir Charles Bright, Mr. (afterward Sir C. W.) Siemens, Mr. Lionel Gisborne, and Mr. H. C. Forde were mainly associated with them as engineers and electricians. The line which met, however, with the most complete and lasting success was the first cable to India, laid (by Sir Charles Bright) in several sections along the Persian Gulf in 1863-’64. In this undertaking Messrs. Bright & Clark (engineers to the Government) introduced a complete system of electrical and mechanical testing. Every joint was, for the first time, efficiently tested, and the insulated core submitted to a hydraulic pressure representative of that which it would experience when laid.[55] A formula was also arrived at by an elaborate series of experiments for the effect of temperature on the insulation, which showed how enormously the resistance of gutta-percha increased by consolidation when submitted to the low temperatures of the bottom of the ocean. Chatterton’s compound had been already introduced for adhering the gutta-percha envelope to the wires, as well as for cementing together the different insulating coats; but Bright & Clark’s preservative composition for the iron armor was first used in this enterprise. This mixture not{173} only evades the oxidation that iron wires, even when galvanized, are subject to, but resists the attacks of the teredo and other objectionable animal life. Moreover, besides the type of cable being eminently suitable, the manufacture was carried out with extreme care and with all the advantage of experience and improved methods.[56] Completion of Pioneer Stage.—With the successful termination of the above enterprise, forming the first telegraphic connection between the United Kingdom, Europe, and India, the science of constructing and laying submarine telegraphs was pretty definitely worked out, and no very striking departure has since been introduced. The pioneer stage may, indeed, at this juncture, be said to have reached completion. For this reason the rest of our narrative on the Atlantic cable will be told more briefly—though at greater length than the contents of this chapter, recounting only the stepping-stones to what was to follow.{174} <h2>PART IV COMMERCIAL SUCCESS</h2> {176} <div style="break-after:column;"></div>

1 of 2

2 of 2