MARINE SURVEY

Timaru Herald, Volume CXLIII, Issue 20929, 7 January 1938, Page 6

MARINE SURVEY

ENDEAVOUR’S WORK CHANGES MADE IN CHARTS By Telegraph—Press Association AUCKLAND, January 6 Having completed the second section of the marine survey which is being made of the New Zealand coastline, the Admiralty survey ship Endeavour has left Auckland for Mercury Bay. Since she arrived in New Zealand last June the Endeavour has made a thorough survey of the Hauraki Gulf and the Firth of Thames, and now she will spend until the end of next June surveying the coastline up to the north end of Great Barrier Island. The Endeavour's work follows that done in a less painstaking and a more hurried fashion by Royal Navy ships since 1845, and the essential difference between past surveys and the one started by the Endeavour is that whereas those made previously have left many gaps in marine charts, the Endeavour’s survey is of a completeness that should be adequate for centuries. It is a tribute to the work of the earlier marine surveyors that Captain A. G. N. Wyatt, commander of the Endeavour, and his officers have been able to make very few alterations to their charts, although the new ones, by reason of the undoubted superiority of the equipment available, are necessarily much more detailed and complete.

Several Aitterations

Here and there alterations have been made. For instance, between Waiheke Island and Motulhi Island the Endeavour has charted several rock pinnacles that rise to Within a small distance of the surface of the water, although, said officers of the Endeavour, Auckland’s yachtsmen are apparently loath, to believe the accuracy of the Endeavour’s discoveries. The coastline of Waiheke Island has also been differently mapped in several places as a result of the Endeavour’s work. About half a mile has been taken off existing maps and charts at Thumb Point, and othersections at Thompson Point, Carey Bay, and Onetangi have had to be subtracted. In the Firth of Thames considerable attention was paid by the Endeavour to a report that a rock within a short distance 'of the surface existed about two miles south-west of Dead Man’s Point on the Coromandel Peninsula. This rock is marked on present charts as being of doubtful existence, although local fishermen have always believed it to be there. Captain Wyatt spent two days dragging a patch of sea two square miles in area in search of the rock and as a result it has been conclusively proved that there is no such pinnacle in this particular area.

200 Miles Surveyed

Since she began her survey, the Endeavour has charted about 200 miles of coastline and in the Firth of Thames alone she made 500 square miles of soundings, crossing each square mile five times, so that her sea mileage here was about 2500. The thoroughness with which the work is being done can only be appreciated from an examination of the rough charts made. These show an enormous volume of soundings. The work being dorie by the Endeavour is of a type which cannot possibly be hurried if the results are to be permanent. The only available data about the Firth of Thames is supplied by a chart which was originally prepared over 85 years ago. Then a Royal Navy ship charted the whole of the New Zealand coastline in five years, which meant that although the main outlines and soundings have been accurate an extraordinary amount of open and uncharted space has been left. When the Endeavour was sent out to fill in these gaps and check the work already done, it was stated that 10 years would probably be taken to complete the whole of the New Zealand coastline. If the survey is to be done as thoroughly as the Endeavour has started it, however, it seems possible that 20 years will be necessary. One interesting result of the Endeavour’s work has been the demonstration that the earlier naval and Harbour Board surveys of the main approach to Auckland harbour were extremely accurate, for the present survey has resulted in no alteration to this section.

Shore Camp

At Mercury Bay a shore camp will be established, and while the parent ship is charting in deeper water her motor-boats will be entrusted with the task of surveying the coastline and preparing a chart of the harbour. The camp will also serve as a base from which stores and mail may be collected at intervals, for it is the intention of Captain Wyatt to return to Auckland for coaling about once every four weeks instead cf the fortnightly periods so far observed. The ship will come to Auckland in June for a refit and will stay in port for about four months while fair charts, or those which will in future be the official charts Of the New Zealand coastline, are prepared.