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bably from not finding fresh water for a colony sufficiently near to the entrance.

Point Nepean is in latitude 38° 18′ south. The longitude from twelve sets of distances taken by lieutenant Flinders in the port, and six others by me ten days before arriving, the particulars of which are given in Table V. of the Appendix to this volume, is 144° 30½′ east; but these observations being mostly on one side of the moon, the corrected longitude by time keepers, 144° 38′ east, is preferred.

No observations were taken in the port for the variation of the compass; but at seven leagues to the south-south-west of Point Nepean, azimuths gave 3° 41′ when the ship's head was at N.E. by E. ½ E., and an amplitude at N.N.E. ½ E., 6° 48′ east. The mean of these, corrected to the meridian, will be 7° 30′, or half a degree less than at King's Island; I therefore take the variation in Port Phillip to have been generally, 7°, though at some stations it seemed to have been no more than 6° 30′ east.

The rise of tide is inconsiderable in the upper parts of the port; near the entrance it is from three to six feet. By the swinging of the ship, which however varied at different anchorages, it appeared to be high water two hours and a half after the moon's passage; but at Point Nepean, the time of high water by the shore is said by Mr. Grimes to be only one hour after the moon. At Western Port, Mr. Bass found high water to take place half an hour after the moon's passage, and the tide to rise from ten to fourteen feet. This great increase, in a place so near, seems extraordinary; but may perhaps be accounted for by the meeting of the tides from two entrances, whilst Port Phillip has only one, and that very narrow.