USEFUL NAVY JOB.

Auckland Star, Volume LXVII, Issue 274, 18 November 1936, Page 9

USEFUL NAVY JOB.

COOK STRAIT CABLE.

ROUTE FORTY MILES LONG.

HUNDREDS OF SOUNDINGS

The New Zealand Division of the Royal Navy is rendering a valuable service to the engineering branch of the Post Office in connection with its preparations for laying a new single-core high-frequency telephone cable across Cook Strait. The route from Lyall Bay in the North Island to the mouth of Blind River, Marlborough, is 40 sea miles long, and it is of the greatest importance that the Department should be in possession of detailed information regarding the nature of the bottom, so as to secure the best possible bed for the cable. The Post Office engineers have collected a good deal of data from time to time while laying other cables and during repairing operations, and this has enabled them to select what appears to be a very suitable route along which the greatest depth is 1200 ft, this being found approximately half-way across Cook Strait. There are two "deeps" on the route, and it is important to ascertain the exact conditions in their vicinity, so as to avoid abrupt angles and unsupported lengths in the cable. The nature of the bottom is generally sandy, except for 10 miles out from Lyall Bay, where patches of rock render it necessary to exercise great care in selecting a safe bed for the cable.

Marine surveys and the taking of soundings constitute an important part of naval training, and tlie Whakakura's personnel is thoroughly experienced in this work, "the ship being fitted with a special sounding boom and soundisg machines. The Wakakura is now engaged taking a line of soundings at half-mile intervals alonjr the proposed cable route, and will also sound similarly on two parallel lines half a mile north and south, as well as closely investigating the conditions 10 miles out from Lyall Bay. Samples of the bottom vill obtained at each soundling.