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THE TELEGRAPHIC CABLE.
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can never be used. The reason why it has lost its power is, of course, mere conjecture; but it is most probable that the copper conducting wires are broken; every experiment made in 1857, and every one in 1858, save the final one, showed that the cable was too heavy, inasmuch as it parted, its own weight being the chief, if not the only cause.

"The copper wires being straight, and the iron outside covering being spiral, they were unequal to the strain and parted, perhaps one, perhaps two, or three, or all. When the fractures were fresh, the electric fluid might leap the chasm; but as they became corroded it would fail to do so.

"He believed 'that an electric cord, not cable, should be laid,' and regarded the 'practicability of a submarine telegraph between Europe and America as a certain thing.' He had foretold the existence of a great Telegraphic Plateau, so named by him; and before the invention of Brooke's deep sea sounding-lead and the soundings made by it, had mapped it out before the world. On this plateau the greatest depth of water does not exceed two miles; it stretches from Newfoundland to Ireland, and across it are no running waters, nor any abrading forces. On it lie the smallest shells; which if dried would float in the air like motes, being scarcely, if at all, visible to the naked eye, and as perfect as if they had been wrapped in down. These were shells of animals living near the surface, which had sunk after death to the quiet depths below.

"If such light substances would sink to the depth of two miles and lie unharmed there, a light wire, protected by any insulating substance, would sink to the same depth, and lie for ages in equal freedom from disturbing forces. Some heavier arrangement (cable possibly) would be required in the shallower waters at each end near shore, where tides affected the bottom.

"Such an achievement places man, as it were, in a higher