SECRETS OF THE SEVEN SEAS

Evening Star, Issue 22367, 17 June 1936, Page 5

SECRETS 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 Hydrographer of the Navy (Rear-admiral .T. A. Edged) on the Surveying Service for 1935. writes Lieutenant-commander Hugh Longden, in the ‘ Daily Mail.’ During the year 358 new rooks or dangers were notified by Admiralty “ Notices to Mariners,” and of these 57 wrecks and 23 obstructions were actually chartered. Fourteen shoals or rocks, 23 wrecks, and six obstructions were notified as being non-existent or as having been removed. The reported existence of a reef in the middle of the Indian Ocean, nearly a thpusand miles away from the base of 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 “ Notices 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 he 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 chartered 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 10-fathom bottom. It was only discovered in 1890 by a ship striking at a cost of 133 lives out of 282 on board. Later, it was charted by the Paluma. Then there is the Maeburn Rock, off the east coast of Queensland, situated on the track taken by all pilot's. 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 Scalark, sounding with lead-lines 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 onr surveying ships are now equipped with the Admiralty pattern echo sounding machines which in shallow water are accurate to three inches. The deepest sounding only takes ](! seconds to record, and it is accurate to within about 3l)ft.