Gutta percha, its discovery, history, and manifold uses.

Date:
1851
Catalogue details

Licence: Public Domain Mark

Credit: Gutta percha, its discovery, history, and manifold uses. Source: Wellcome Collection.

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    tlierefore be but a few inches apart, and if the nearest con¬ ductor be a wire that starts from London, and communicates with the ground at Edinburgh, or Paris, or Calcutta, by that road it will go with the swiftness of light, exciting on its way the ordinary electrical phenomena in every apparatus set to mark its progress and register its tidings, then returning straight through the earth and water. This viewless spirit, however, like more material beings, will never take more trouble than it can help, and if, consequently, it can get to the ground—by a conductor again—before it reaches its destination, it will do so and leave the messages beyond its turning point undelivered. To insulate the wire from the ground, therefore, as well as from any other body that might accomplish the too friendly purpose of a conductor back again, has been a prime concern with the constructors of electric telegraphs. No expedient so well elfects this as a casing of Grutta Percha. By land it answers perfectly, along the dark damp walls of the railroad tunnel, and even when the covered wire is imbedded in the earth, as has been proved upon the London and North Western Bailway. Still more remarkable is its success under water ; Edward Highton, Esq., Telegraphic Engineer to the railway just mentioned, writes :— “ I have had, for experimental purposes, some of the Grutta Percha Covered Wire, laid in the Gierman Ocean. It has now been submerged in the sea for more than a year. Where the wire is placed, marine insects eat away and completely destroy pine timber, of great thickness, in less than seven years. The Grutta Percha covering to the wire, however, remains intact, although a portion of it is fastened to timber, which, owing to the ravages of these insects, has already been renewed. Ep to this period, I have every reason to be satisfied with the results of this experiment with Grutta Percha Covered Wires sub¬ merged in the sea.” Accordingly when the bold proposal came forth of uniting Eng¬ land and Erance by telegraph, it was felt at once that only by the aid of Grutta Percha could the great enterprise be accomplished. After innumerable and delicate experiments, the plan was ma¬ tured. Every imaginable precaution was taken to prevent failure.
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