Encyclopædia Britannica, Ninth Edition/Electric Traction > 자유게시판

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As regards economy of energy, we've got in the storage system a extra complicated series of transformation of energy, and subsequently a larger number of items of loss. I imagine this financial system would be at the expense of safety, and that the cable of the long run can be even heavier, more perfect, and extra expensive, than the cable of the present day.-Abstract of Address earlier than the Statistical Society. Notwithstanding, Mr. Newall's partiality for light cables, he suggests at the shut of his proof what I assume he would consider essentially the most excellent type of cable. The very light cable invented by Mr. Varley (No. 21) admits of being laid by having the strain taken off the core by the two hempen strands, the core itself being the third strand of the cable. Mr. Preece described the Jersey cable as having been destroyed by lightning. He would cover the copper with India-rubber, protect this core with steel wires vulcanized, the entire then handed by way of heat; thus insulating all the wires, he would make the cable in a single size, and have no joints.

I have written sufficient to illustrate that the current submarine cable shouldn't be a haphazard thought, but one which has grown out of many failures and hundreds of experiments; all of the rules of manufacture and laying down have been established by nice anxiety and reflection on the part of the able men who gave their energies to this kind of enterprise prior to 1865. We who've come upon the stage since that date have solely discovered that we may not neglect certainly one of all of the recognized ideas, however elaborate each one in every of them, and even then the duty of laying and maintaining this class of property has enough of dangers and anxieties to make one heartily dislike any experiment which can only be advocated for the sake of cheapness in the first cost. There isn't a occasion yet of a nicely-manufactured heavy cable breaking or giving out in deep water after it has been rigorously laid free from defects; however there could also be a lot due to the external protecting conserving it quiet; there has assuredly been a fantastic deal because of the external protecting in the profitable submerging, and there isn't any expertise whatever to justify the assumption that an unprotected core would final, even when laid.

Upward of 30,000 miles of cable have been laid because the report of the committee was printed, eleven years in the past, and much expertise has been gained of the exigencies incidental to submerging, buoying, grappling, and repairing; however no reality has resulted from all that expertise which has established that anyone precaution really useful in the report has been superfluous, whereas much has occurred, which I will not particularize, proving that any attempt to disregard any single precaution has resulted in nice pecuniary loss or utter failure. As a gentle cable, to be manufactured in a terrific hurry, and laid to satisfy some emergency, it has a superb deal of merit, but for a deep-sea cable I'm of opinion that it would be discovered too incomplete and unfinished, and that difficulties can be experienced in laying which aren't directly foreseen, what is electric cable and that there could be no durability even if successfully laid. All cables which have been manufactured and laid upon the principles which have been established in 1859 are but in good working order, and every divergence from these principles has been at greatest however a costly experiment or utter failure.

I've mentioned already that the committee called consideration to the outstanding proven fact that, in virtually all instances, small cables have been discovered liable to mishaps, whereas the heavier the cable the greater had been its durability. Day-after-day of my expertise in watching over the permanence of the 10,000 miles of cable below my care, confirms me within the opinion that too nice warning and vigilance can't be exercised within the making and laying a thread which is to be faraway from all human imaginative and prescient ceaselessly, and designed to earn dividends by persevering with a perfect conductor of electricity. All of the expertise we. I desire to jot down with great respect for the opinions of the talented males who urge the adoption of gentle cables; it's my particular obligation to weigh effectively and with out prejudice all they need to advance; however I feel a cautious investigation into the expertise and apply of the last twenty years establishes conclusively that all mild cables have been short-lived, and that all heavy cables have continued working, typically beneath most antagonistic situations. We're once in a while startled by the announcement that light cables are to be most well-liked to the present iron-clad sort, and the article of this investigation has been to discover what data there are to justify any choice to 1 type of cable over another.