Lieutenant Clerke, ditto 39 38 0
Mr Gilbert, ditto 39 48 45
Mr Smith, ditto 39 18 15 ————— Mean 39 42 12
Mr Kendal's watch made 38 41 30
which is nearly the same difference as the day before. But Mr Wales and I took each of us six distances of the sun and moon, with the telescopes fixed to our sextants, which brought out the longitude nearly the same as the watch.
The results were as follows:—By Mr Wales, 38° 35' 30", and by me, 38° 36' 45".
It is impossible for me to say whether these or the former are the nearest to the truth; nor can I assign any probable reason for so great a disagreement. We certainly can observe with greater accuracy through the telescope, than with the common sight, when the ship is sufficiently steady. The use of the telescope is found difficult at first, but a little practice will make it familiar. By the assistance of the watch, we shall be able to discover the greatest error this method of observing the longitude at sea is liable to; which at the greatest does not exceed a degree and a half, and in general will be found to be much less. Such is the improvement navigation has received by the astronomers and mathematical instrument- makers of this age; by the former from the valuable tables they have communicated to the public, under the direction of the Board of Longitude, and contained in the astronomical ephemeris; and by the latter, from the great accuracy they observe in making instruments, without which the tables would, in a great measure, lose their effect. The preceding observations were made by four different sextants, of different workmen. Mine was by Mr Bird; one of Mr Wales's by Mr Dollond; the other and Mr Clerke's by Mr Ramsden; as also Mr Gilbert's and Smith's, who observed with the same instrument.
Five tolerably fine days had now succeeded one another. This, besides giving us an opportunity to make the preceding observations, was very serviceable to us on many other accounts, and came at a very seasonable time. For, having on board a good quantity of fresh water, or ice, which was the same thing, the people were enabled to wash and dry their clothes and linen; a care that can never be enough attended to in all long voyages. The winds during this time blew in gentle gales, and the weather was mild. Yet the mercury in the thermometer never rose above 36; and was frequently as low as the freezing point.
In the afternoon having but little wind, I brought-to under an island of ice, and sent a boat to take up some. In the evening the wind freshened at east, and was attended with snow showers and thick hazy weather, which continued great part of the 16th. As we met with little ice, I stood to the south, close hauled; and at six o'clock in the evening, being in the latitude of 64° 56' S., longitude 39° 35' E. I found the variation by Gregory's compass to be 26° 41' W. At this time the motion of the ship was so great that I could by no means observe with any of Dr Knight's compasses.
As the wind remained invariably fixed at E. and E. by S., I continued to stand to the south; and on the 17th, between eleven and twelve o'clock, we crossed the Antarctic Circle in the longitude of 39° 35' E., for at noon we were by observation in the latitude of 66° 36' 30" S. The weather was now become tolerably clear, so that we could see several leagues round us; and yet we had only seen one island of ice since the morning. But about four p.m. as we were steering to the south, we observed the whole sea in a manner covered with ice, from the direction of S.E., round by the S. to W.