The variation of the Compass I found to be 4 degrees 46 minutes Easterly, this being the mean result of a great number of Trials made by 4 of Dr. Knight's needles belonging to the Azimuth Compasses, all of which I judged to be good ones, and yet when applied to the Meridian line I found them not only differ one from another sometimes a degree and a half; but the same needle would differ from itself more or less, the difference sometimes amounting to half a degree, both at the same time and on differant days. This will in a great measure account for the seeming errors that may, upon a nice examination, appear to have been made in observing the Variation inserted in the Course of this Journal. This variableness in Magnetick Needles I have many times and in many places experienced both ashore and on board of Ships, and I do not remember of ever finding two Needles that would agree exactly together at one and the same time and place, but I have often found the same Needle agree with itself for several Trials made immediately one after another.* (* These discrepancies result from imperfections in the suspension and mounting of the needles, and are only absent in instruments too delicate for ordinary sea service.) However, all this is of no sort of consequence to Navigation, as the Variation of the Compass can always be found to a degree of accuracy more than sufficient for all nautical Purposes.

I have before hinted that these People have an Extensive knowledge of the Islands situated in these Seas. Tupia, as well as several others, hath given us an account of upwards of 70; but, as the account they have given of their situation is so Vague and uncertain, I shall refer giving a list of them until I have learnt from Tupia the Situation of each island with a little more certainty. Four of these islands--viz., Huaheine, Ulietea, Otaha, and Bolabola* (* These islands are now known as Huaheine, Raiatea, Tahaa, and Borabora or Bolabola, and are under French sovereignty.)--we were informed, lay only one or two days' sail to the Westward of George's Island, and that we might there procure Hogs, Fowls, and other refreshments, Articles that we have been very sparingly supply'd with at this last Island, as the Ship's Company (what from the Constant hard duty they have had at this place, and the two free use of Woman) were in a worse state of health than they were on our first arrival, for by this Time full half of them had got the Venerial disease, in which Situation I thought they would be ill able to stand the Cold weather we might expect to meet with to the Southward at this Season of the Year, and therefore resolved to give them a little time to recover while we ran down to and explored the Islands before-mentioned.