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Show IN THE OCEAN'S DEPTHS. I How a Submarine Telegraph Line Is Laid Ingenious Methods j ol Determining the Route of a Cable, The events of the .nast two years i have been given-an iV creased Interest in the remoter parts ci the globe thtH has never been so widespread among our people as .now. The Philippines, the Transvaal and China have ceased: to be- mere geographical facts, but have become real places of which we know something and from which we demand news with as slight delay as ' possible. The telegraphic cabtes therefore today : hold an important place in minds that previously had not dissolve in water. So fax tnt one material has been discovered that ful-, ful-, fills all the conditions. That la gutta percha, a gum that iB easily worked; and whose only drawback Is Its scar-i city. . ! When the pure gum is heated to-aboutl50 to-aboutl50 degrees Fahrenheit ft becomes, very soft and. plastic, so that It can be rolled or pressed into shapes that it retains when cold. Advantage is ta-, ken of th.is in making cables, for th heated eum is forced throu- a cvlin-! der surrounding the core and as the core is drawn through a die-piece a thin layer of gutta percha Is left on It. This is repeated as often as is required and the core Is tires covered with a series of gutta percha Jackets tht extend ex-tend without break or seam from end Jr jjd, and, from the electrical stand-poiuc, stand-poiuc, the cable is done. In this condition con-dition it would be exposed to many mishaps that might Injure tho envel-i ope and destroy the working of tre cable, so a sheathing Is pnt around it. given then but little consideration. It is strange how few people know anything of the oceanic telegraphic service, says a writer in the Washington Washing-ton Star. A vague idea that it is carried car-ried on by "cables" Is about all that the ordinary person possesses, but what a cable is. how it is operated or what difficulties lie in the way of Its construction, are all unknown to the bulk of well-informed people. ' The accounts ac-counts of them are generally so incumbered incum-bered with technicalties as to be almost al-most unintelligible to unprofessional : readers, and, in consequence, they are wrapped in more mystery than are many things that enter into everyday life. Most people think that there is no more difference between submarine and land telegraphy than there is between be-tween an overhead and an underground under-ground trolley- line, but this is not ' true. They are absolutely distinct, i and have little more in common than ; have a great railway system and a horse car line, if so much. Both telegraphic tele-graphic systems use electric currents to transmit signals over a cunducting Wire, as both the . railway and the horse car. line use vehicles that move on a track, "but all else. is different, . In order to understand, why a . route tor a cable is always sought with much care the structure of the cable itself should be known, for on its safety depends de-pends the success of the enterprise. A cable consists of a "core" of wire that i i-ooiw th imnortant Dart of the " whole, and a covering of some Insulat-, Insulat-, ing and protecting material. The core is made of strands of copper woven in-. in-. to ;a.Tope-Jike cord, and Weighs from 70 to 400 pounds per mile for the shore ends that have to stand the surf are much stronger, and . heavier than the deep sea portions. The stranded form is much mqre flexible than the solid rod. and is not so-apt to be bro-, bro-, ken in laying-.. The core Is coated with a mixture of resin,, tar and gutta per-. per-. cha, known , as "Chatterlon's com-' , . pound,'? that te to act as a cement and hold the insulation firmly to the .wires. The insulating ma-terial must com-r ply:with" many" requirements. It must not- conduct1 electricity and must pre-"ypnt pre-"ypnt "leakage as 'much as possible; it ; must be thoroughly' waterproof , for the sea water. will soon- corrode' the copper if It reaches-it. and will' steal the current cur-rent ' if J there be the smallest- hole' through wh'icti It may reach tie wires. If inVs't '.'resist the chemfcal action ol ' :- the ' water 'on ' itself. ..and ' it . must be flexible :and tough, , so that the cable : may be coiled into a small space cm board ship 'and-run over pulleys wren being laid - without cracking or tearing. tear-ing. Finally, it !must be ' something that does :npt' decay readily and' does |