The Gutta Percha Company – link to Eastern Extension Telegraph Company and Hong Kong
The Gutta Percha Company
The following paragraphs are extracted from Bill’s article, with his permission, which can be found on his large and absorbing website. The article can be read in full via the link below, along with an extract from the book “London by day and night:or, Men and things in the great metropolis” by David W. Bartlett, which describes a visit to the Gutta Percha Company’s factory on Wharf Road, London, in 1850, right at the beginning of the undersea cable era.
“Introduced to Britain in 1843, gutta percha is the gum of a tree native to the Malay Peninsula and Malaysia. At that time there was no application for the material as cable insulation; this would come later. Unlike india rubber, which must be vulcanised to be useful as an insulator, gutta percha is thermoplastic, softening at elevated temperatures and returning to its solid form as it cools. This made it easy to mould gutta percha into many decorative and functional objects, either by pressing the heated material into cold moulds, or by extrusion.
The Gutta Percha Company was established in 1845, and made chessmen, mirror surrounds, tea trays, commemorative plaques, animal figures, inkstands, and even a full-size sideboard, among many other decorative items. Industrial products included machinery belts, acid-tank linings, and tubes. The extrusion machinery used to make the tubes, modelled it is said on Italian pasta machines, was soon adapted for use in wire covering. This technique was used first to insulate landline cables, and later for submarine cables.
After the failure of their first cable in 1850, the brothers John and Jacob Brett laid a successful submarine cable from Dover to Calais in 1851. This used two layers of gutta percha insulation and an armoured outer layer. Gutta percha proved to be an ideal insulator for submarine cables, and as a further benefit for cable use it was found that gutta percha’s insulating properties improved under the pressure and temperature conditions of the ocean bed. Gutta percha remained the prime material for submarine cable insulation for over 80 years.
Previous attempts to use gutta percha as cable insulation involved compressing two sheets of gutta percha around the wire, but this left two seams in the insulation. The Gutta Percha Company’s tubes were seamless, and proved their value in insulating the 1850 and 1851 cross-channel cables, although the covering process had not yet been perfected. The conductors of the 1851 cable had an irregular coating of gutta percha, which had to be shaved away in places, and suffered from air holes and voids. Nonetheless, the cable was a success, and much additional business followed. Producing cable core became the company’s main operation, consuming a significant proportion of the output of gutta percha, imports of which exceeded a thousand tons a year by 1861…”
Source: http://atlantic-cable.com/Article/GuttaPercha – Bill Burns’ article
See: Bill Burns’ website http://atlantic-cable.com/
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