In the bearings taken at different parts within the group, the variation seemed to differ from 2 deg. 30’ to l deg. 30’.  The largest variations were on the east sides of the islands, and the smallest on the west sides; seeming to show an attraction of the land upon the south end of the needle.  On board the ship, when coasting along the east side of Vanderlin’s Island, and the whole group lay to the west, the variation appeared from the bearings to be as much as 4 deg. east.

The best observation made on the tide, was on the 23rd, during my boat excursion to the south end of Vanderlin’s Island.  On that morning the moon passed over the meridian at sixteen minutes past ten, and the perpendicular movements of the tide were as follows.  At seven o’clock, when I left the shore, the tide was falling; on landing at nine it was stationary, and appeared to be low water; at noon it rose fast, and at three was still rising, and continued so to do, but slowly, until seven in the evening, The tide then began to fall; but after subsiding one foot, it rose again until ten o’clock, and had then attained its greatest height.  Low water took place therefore about an hour before, and high water at eleven hours and a quarter after the moon passed the meridian:  the rise appeared to be from four to seven feet.  At Wellesley’s Islands high water had taken place an hour and a half earlier, which seems extraordinary, if, as it necessarily must, the flood come from the northward.  I think it very probable, that the tide in both places will follow what was observed in King George’s Sound on the South Coast; where high water, after becoming gradually later till midnight, happened on the following day before seven in the evening, and then later as before.

The break of three hours in the tide here, is somewhat remarkable:  it was not observed amongst Wellesley’s Islands, where the tide ran twelve hours each way; but was found to increase as we proceeded west and northward until it became six hours, and the tides assumed the usual course.

CHAPTER VIII.

Departure from Sir Edward Pellew’s Group. 
Coast from thence westward. 
Cape Maria found to be an island. 
Limmen’s Bight.  Coast northward to Cape Barrow:  landing on it. 
Circumnavigation of Groote Eylandt. 
Specimens of native art at Chasm Island. 
Anchorage in North-west Bay, Groote Eylandt;
with remarks and nautical observations. 
Blue-mud Bay.  Skirmish with the natives. 
Cape Shield. 
Mount Grindall. 
Coast to Caledon Bay. 
Occurrences in that bay, with remarks on the country and inhabitants. 
Astronomical and nautical observations.

[NORTH COAST. GULPH OF CARPENTARIA.]

MONDAY 27 DECEMBER 1802

(Atlas, Plate XIV.)