COOK STRAIT TELEPHONE.

Hawera Star, Volume XLV, 9 March 1926, Page 9

COOK STRAIT TELEPHONE.

THE CABLE ARRIVES. The now telephonic cable that is to span Cook Strait arrived in Wellington from England by the Tonganro, and is being transferred to the foretank ox the Tutanekai forthwith. 1 The actual work of laying the cable will not be proceeded with at once, as the Government steamer is undergoing an extensive overhaul, and it may be over a fortnight before she is in a condition to put to sea, but that will not delay the transhipment of the seventy miles of cable into her hold (says the Domml°The new cable is to be laid between Ly.all Bay at this end and Blind River (near Seddon) in Marlborough on the other side of the Strait. As it will be necessary to connect it up with stations at either end there will be a good deal of land work involved in the burying of it between Lyall Bay and Courtenay Place, whence it will be conducted in existing ducts to the Stout Street Central Exchange, and the five mile front the beach at Blind River to the new station to be built for its reception at Seddon township. Siemann’s, who made the new cable, i.n! also supplying the machinery for the repeat station at Seddon. In long distance telephony the sound has to be amplified at certain points and relaid, precisely in the manner that wireless signals "are amplified, by the use. of valves, etc. This requires the erection rj a room about Isft by 18ft at Seduon to contain the repeating apparatus and switch board that lias not yet armed in the country. This will be adequate to serve Nelson, Marlborough and Canterbury. Whether another repeat.ng station will be needed further south remains to be seen by the experience of the one now to be erected at Seddon. The marvel of this four-core continu-ous-loading cable is that three conversations (engaging six persons) and three Morse messages, may be sent over the cable at one and the same time, without the slightest risk of interference one with the other, and yet the cable is only a two-pair one; that is to .say, there are only four copper wires Tunning through the heart of the cable. The new cable is not of uniform thickness throughout its ' entire length from station to station. The deep sea length is one and three-quarter inches in diameter, whilst the shore ends are two inches in diameter, whilst the armouring is proportionately heavier in the shore ends than the deep•sea portions of the cable, for the reason that extra strength is required in the cable as it reaches the shore, owing to the greater action of tides and surf. Round the central core containing the allimportant copper wires, there are seventeen especially prepared iron wires, whilst on the shore-end portions there are only twelve, but the latter ire considerably stouter. The composition of the cable, which is unique in (hose parts, consists of the four copper wires, each contained in the centre of four circular compartments made by i running tube of the finest brass tape, which makes the cable invulnerable to the attack of the torpedo, the copper wires being encased in belata (a form of gutta percha) within the brass tape "irclcs. Even inside the belata filling bound close to the copper wires is the finest of iron wire—thread-like in character —which gives the continuous loading required. The brass tape ducts are geometrically placed in the centre of the cable, and round them is the usual jute worming; then the stout iron wire armouring, which 'in turn is protected with .jute yarn and a bituminous compound. Taking into consideration all the work that has to be done in connection with the cable afloat and ashore, it is not expected that the new cable will be available for everyday use for at least a month yet.