Page:A Voyage to Terra Australis Volume 2.djvu/58

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At our anchorage on the west side of the bay, Mr. Flinders took azimuths when the ship's head was S.E. by E., which gave 6° 31′ by one compass; before he had done, the ship swung to the flood tide with her head W.N.W., and two other compasses then gave 11° 27′ and 11° 4′: the mean corrected to the meridian, will be 8° 46′ east.

At an anchorage towards the east side of the bay, the same officer observed the variation with two compasses, when the head was east, to be 4° 49′, or corrected, 7° 21′ east.

The difference in Strong-tide Passage, where the land was one mile to the south-south-east on one side, and the same to the west on the other, was still more remarkable; for when the head was N.E. by N., an amplitude gave me 9° 10′, or corrected, 10° 34′ east.

There might have been an error in any of the ship observations of half a degree; but I am persuaded that the attraction of the land, sometimes to the east and sometimes west, as the ship was near one or the other side of the bay, was the great cause of the difference in the corrected results; and it will presently be seen, that the effect on a neighbouring part of the coast was much more considerable.