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Kanguroo Island.]

The variation observed from two compasses on board, with the head south-westward, was 6° 31′ east; but when the ship swung to a tide coming from east-north-east; the change in the bearings of different objects showed the variation to be about 4° less. The true variation I deduce to be 4° 13′ east; which is an increase upon what was observed on the west side of Cape Spencer, of 2°; although the distance be no more than twenty-four leagues, and the previous increase from Cape Catastrophe had been almost nothing. It seems probable that the existence of magnetic bodies in the land to the north-westward, and perhaps also in Kanguroo Island and Cape Jervis, was the cause of this change in the direction of the needle.

From appearances on the shore, I judged the rise of tide to be about six feet. The flood came from the east-north-east, twice in the day, and by the swinging of the ship, ceased at two hours and a half after the moon's passage; but the time of high water was afterwards found to be later by one hour and a half.