The variation of the compass was found to be,
| At | Annamooka, on board, | 8° | 30ʹ | 31⁄2ʺ east. | |
| Anchor off Kotoo, between Annamooka and Hapaee, | 8 | 12 | 291⁄2 | ||
| Anchor off Lefooga, | 10 | 11 | 40 | ||
| Tongataboo, on board, | 9 | 44 | 51⁄2 | ||
| Ditto, on shore, | 10 | 12 | 58 |
I can assign no reason why the variation is so much less at and near Annamooka, than at either of the other two places. I can only say, that there is no fault in the observations; and that the variation ought to be more at Annamooka than the above, as it has been found to be so to the northward, southward, eastward, and westward of it. But disagreements in the variation, greater than this, even in the same needle, have been often observed. And I should not have taken notice of this instance, but from a belief that the cause, whatever it is, exists in the place, and not in the needles; for Mr. Bayly found the same, or rather more difference.
The tides are more considerable at these islands, than at any other of my discoveries in this ocean, that lie within the tropics. At Annamooka it is high water, on the full and change days, nearly at six o’clock; and the tide rises and falls there, upon a perpendicular, about six feet. In the harbour of Tongataboo, it is high water, on the full and change days, at fifty minutes past six. The tide rises and falls on those days, four feet nine inches; and three feet six inches at the Quadratures. In the channels between the islands, which lie in this harbour, it flows near tide and half-tide; that is, the flood continues to run up near three hours, after it is high water by the shore; and the ebb continues to run down, after it is flood by the shore. It is only in these channels, and in a few other places near the shores, that the motion of the water or tide is perceivable; so that I can only guess at the quarter from which the flood comes. In the road of Annamooka, it sets west south-west, and the ebb the contrary; but it tails into the harbour of Tongataboo from the north-west, passes through the two narrow channels, on each side of Hoolaiva, where it runs with considerable rapidity, and then spends itself in the lagoon. The ebb returns the same way, and runs with rather greater force. The north-west tide is met at the entrance of the lagoon, by one from the east; but this, as I have before observed, was found to be very inconsiderable.
END OF THE FIFTH VOLUME.
London:
Printed by A. & R. Spottiswoode,
New-Street-Square.
Footnotes
[1]. Two voyages for discovering a North-West passage, through Hudson’s Bay, were then performed; one under the command of Captain Middleton, in his Majesty’s ships the Furnace, and the Discovery Pink, in 1741 and 1742; the other under the direction of Captains Smith and Moore, in the ships Dobbs and California, fitted out by subscription, in 1746 and 1747.