We perceived the sea now covered over with luminous spots, much resembling so many lanthorns floating on its surface; whether this appearance proceeded from the spawn of fish, which may swim in small collected quantities, or from that animal of a jelly-like substance, which is known to sailors by the name of blubber, I cannot tell, but I believe the latter, as we had seen in the day some of a large size. We had now also many sea-birds about the ship, such as albatrosses, gulls of different kinds, and a large black bird, which, in the motion of its wings, had much the appearance of a crow, but its neck and wings are longer than those of that bird, and it is altogether larger. On the 4th of January we had a number of good observations for the longitude, and as it was probable they might be the last we should have an opportunity of taking, before we should make Van Diemen's Land, the result, which gave 135 deg. 30' east, was marked with chalk in large characters on a black painted board, and shown over the stern to the convoy; at the same time a signal was made which had been previously appointed. On the 6th in the evening, as I intended running in for the land all night, I made the signal for the convoy to close, and to drop into the Sirius's wake, under an easy sail; the night was dark, but clear in the horizon, so that we could see near two leagues a-head. This night the aurora austreales were very bright, of a beautiful crimson colour, streaked with orange, yellow, and white, and these colours were constantly changing their places: the highest part was about 45 deg. above the horizon, and it spread from south by east to south-south-west. On the next morning at sun-rise, one of the transports having pushed a little a-head, made the signal for seeing the land, in which, however, she was mistaken: we at this time judged ourselves not less than 33 or 34 leagues from it, deducing our distance from the last lunar observation. It may not be improper, before I proceed farther, to observe of the compass, that its westerly variation decreased from the longitude of 54 deg. 30' east, where it was greatest, (viz. 32 deg. 10' west,) to longitude 135 deg. 30' east, where it was 1 deg. 00' east.