On the 1st of January, being then in the latitude of 48° 41' S. longitude 76° 50' E., the variation was 30° 39' W.; and in the next day, in the latitude of 48° 22' S. longitude 80° 22' E., it was 30° 47' 18" W. This was the greatest variation we found in this passage; for afterward it began to decrease, but so slowly, that on the 3d, in the evening, being then in the latitude of 48° 16' S. longitude 85° E., it was 29° 38' W.
Thus far we had fresh gales from the W. and S.W., and tolerably clear weather. But now the wind veered to the N. where it continued eight days, and was attended with a thick fog. During this time we ran above 300 leagues in the dark. Now and then the weather would clear up, and give us a sight of the sun; but this happened very seldom, and was always of short continuance. On the 7th I hoisted out a boat, and sent an order to Captain Clerke, appointing Adventure Bay, in Van Diemen's Land, as our place of rendezvous, in case of separation before we arrived in the meridian of that land. But we were fortunate enough, amidst all this foggy weather, by frequently firing guns as signals, though we seldom saw each other, not to lose company.
On the 12th, being in the latitude of 48° 40' S. longitude 110° 26' E. the northerly winds ended in a calm; which, after a few hours, was succeeded by a wind from the southward. This, with rain, continued for twenty-four hours, when it freshened, and veered to the W. and N.W., and brought on fair and clear weather.
We continued our course to the eastward, without meeting with any thing worthy of notice, till four o'clock in the morning of the 19th, when, in a sudden squall of wind, though the Discovery received no damage, our fore-top-mast went by the board, and carried the main-top-gallant-mast with it. This occasioned some delay, as it took up the whole day to clear the wreck, and fit another top-mast. The former was accomplished without losing any part of it, except a few fathoms of small rope. Not having a spare main-top-gallant-mast on board, the fore-top-gallant-mast was converted into one for our immediate use.
The wind continued westerly, blew a fresh gale, and was attended with clear weather, so that scarcely a day passed without being able to get observations for fixing the longitude, and the variation of the compass. The latter decreased in such a manner, that in the latitude of 44° 18' S. longitude 132° 2' E., it was no more than 5° 34' 18" W.; and on the 22d, being then in the latitude of 43° 27' S. longitude 141° 50' E., it was 1° 24' 15" E. So that we had crossed the Line where the compass has no variation.