GRIM SECRETS.

Ashburton Guardian, Volume 56, Issue 236, 18 July 1936, Page 2

GRIM SECRETS.

DANGERS OF THE SEVEN SEAS. A wealth of interesting and useful information about the sea and its mysteries is-contained in the slim eightpage leaflet which constitutes the latest report of the Uydrographer of the Navy (ltear-Admiral J. A. Edgell) on the Surveying Service for 1935, writes Lieutenant-Commander Hugh Longden in the “Daily Mail.” During the year 358 new rocks or dangers were notified by Admiralty “Notices to Mariners,” and of these 57 wrecks and 2 obstructions were actually charted. Fourteen shoals or rocks, 2 wrecks, and six obstructions were notified as being non-existent or as having been removed. . The reported existence of a reef m the middle of the Indian Ocean nearly a thousand miles away from the base oi H.M.A.S Moresby was disproved by the Moresby ‘Of our eight surveying ships now employed, four are used in home waters and four on foreign stations. During the winter months, that is, between November and March, the four at home have their complements reduced and are refitted. Every week the Admiralty issues its “Notibes to Mariners.” These detail any new dangers discovered, lightships temporarily out of position or not working, and old dangers cleared. From these the navigator of each ship should correct his charts day by day. It is essential for the safety of a ship that the charts, sailing directions, light lists, and tide tables should be; kept corrected to date. Wrecks may turn over and, in doing so, become either more or less dangerous. They are charted as dangerous or not dangerous according to their depth. One of the most famous rocks is the Quetta off the north-east corner of Australia, in the Adolphus Channel. It is a “pinnacle rock,” isolated on an otherwise level ten-fathom bottom. It was only discovered in 1890 by a ship striking it at a cost of 133 lives out of 282 on board. Later, it was charted l by the Paluma. Then there is the Maeburn Rock off the east coast of Queensland, situated on the track taken by all pilots. It was discovered in 1850 and then lost. Three different surveying ships searched for it, but it was not rediscovered, and safely charted till 1911. The Scalar,k, sounding with leadlines from her boats, found it. It cost her navigating officer two drinks! He had promised them to the first leadsman to find the rock. All our surveying ships are now equipped with the Admira]ty_ pattern echo sounding machines which in shallow water >re accurate to three inches. The deepest sounding only takes 16 seconds to record and it is accurate to within about 30 feet.