NAUTICAL ENQUIRY.

Press, Volume LXI, Issue 18415, 23 June 1925, Page 14

NAUTICAL ENQUIRY.

WRECK OF THE CYRENA

(PHESS ASSOCIATION TBLEOEAM.) WANGANUI, Juue 22.

At the nautical enquiry into the loss of the Cyrena Robert Millor, diver, said that when he went down a second time he endeavoured to locate the obstruction. He found the grapple was embedded in the sand. He walked over an area of 50 square feot. With the strain from the punt above ho did not think that tho grapplo of the punt would be held in tho sand alone. Subsequently he examined the grapple. There were no marks of contact with'iron. So far as he knew no efforts had been made to find the obstaclo since June 6th.

Sir Hazard, Harbojir Board Engineer, was examined regarding the loss of the dredge Kaione's ladder. He said the Kaione left about forty feet of her ladder behind some■where. It was never located. It weighed about 20 tons. No dragging had been done in the locality where the ladder was lost. It was impossible for it to bo shifted by the sea from the place where it dropped. Mr Brodie said the ladder was dropped well south of the moles and had already been the subject of a marine enquiry.

DIRECTION FINDER.

AORANGI CHECKS ERROR.

(SPECIAL TO "THE PBESS.") AUCKLAND, June 22,

The Aorangi, which errived at Auckland from Vancouver yesterday, anchored in Hauxaki Gulf for over two hours to check an error in her wireless direction finding' compiS3. The vessel anchored at about noon in a position midwty between Tiri Island and t.angitoto beacon. Her launch, which is fitted with wireless, was then lowered into the water p.nd was sent away abottt a, mile and a hilf. Keeping that distance, the launch, circled slowly round the Aorangi and reciprocal bearings were then taken. The correct bearings of the launch on each point of the compass were noted by the master and officers on the Aorangi's bridge, and at the same time the bearings of the wireless signals from the launch were noted by the Aorangi's operators by means of the wireless compass. The angle between the correct bridge compass hearing and tho wireless bearing showed the ma>rgin of error. Mariners' ordinary compasses are tested in a somewhat similar manner, but the vessel is generally swung round on a. pivot and the bearings of a distant object arc cheeked on every point of the compass. With an ordinary ship's compass,* the errors «ie caused cither by magnetism in the iron included in the vessel's structure or by the earth's magnetism. These errors can be counteracted 'to a, large extent by placing permanent magnets near the compass. The error of the wireless compass is not caused by magnetism, but by wireless waves being retracted by the metal hull of the vessel. These errors of tho wireless compass can-, not bo adjusted, but when they are known they can be allowed for when tho wireless compass is being used for direction finding purposes.