COOK STRAIT CABLES

Dominion, Volume 10, Issue 3023, 9 March 1917, Page 6

COOK STRAIT CABLES

TWO ,OF THEM OUT OF ORDER

The- Tutanekai is still jit work in Cook Strait seeking to repair two of the five cables crossing that turbulent stretch of water, which are out of order. One of theso\ cables is the one which stretches from Lyall Bay to AVhite's Bay. It has been down for a period of forty years, and was the second laid across tho Strait. It has been patched so often that Mr. J. Orchiston (Chief Electrical Engineer) is a'fraid that there is not much of tho original left. ' Yet there are parts ot tho" original cable left, and these are in such a condition that it is just a matter of luck whether it can be raised to the surface again. Tho Tutanekai got hold of-.the cable the other day, but it snapped before it could bo got on board. Tho public lias only a very faint idea of the trouble that is some : times involved in keeping the Cook Strait cables in good order. The area is regarded as one of the worst in tho world. The first trouble to contend with is tho fierce nature of the tides, which taken together with tho very uneven bottom (which Mr. Orchiston says' roughly resembles Wellington turned npsido down) plays havoc with the cables, exposing them to strains and see-saw action that many an ocean cable does not experience. In one part of the Strait well out from Turakirao Head there is a great hole 410 fathoms in depth, big enough to easily tako Mount Victoria, Then there has been repeated evidence of the existence of sulphur springs about three or four miles off Tom's Rock, quite close to tho entrance to the harbour. Mr. Orchiston exhibits sections of. cable quite sound in its armour of iron wire at one end, but which tapers off at the other, tho iron binding having been eaten away by tho action of the hot sulphur springs. There is no doubt about tho cause of this disintegration of the cable, for there is no evidence of friction, tho sulphur having done its work smoothly and evenly. Still another disturbing influence is the presence of a tiny shell fish, which lodges on the insulation, and as the cable strains it gets through the wire armouring, and chews the gutta-percha insulation round tho cable wire itself. > Having done this, the insect probably gets an electrical shock and retires, but thereafter tho cable is freakish, owing to tho escape of electricity through tho holo, and sooner or later it refuses to work and has to be attended to. The insects are supposed to have been brought to these waters attached to'the bottom of some vessel. They are numerous in the tropics, and are so fond of gutta-percha that it has been found necessary to bind the cables with brass tape. Now that the der stroyer has come to stay in. Cook Strait, all new cable to be laid there will have to be protected in that manner.