Next morning we continued the examination upwards, carrying 4, 3, and 2 fathoms in mid-channel; but at ten o'clock our oars touched the mud on each side, and it was not possible to proceed further. I then landed and took observations in an artificial horizon for the time-keeper, which gave 4' 34" of longitude to the west of the ship, or only two seconds more than was deduced from the bearings. Mount Brown bore S. 72° E., Mount Arden N. 26° E., and my last station on the eminence of red earth S. 6° E. The inlet wholly terminated at one mile and a half to the N. 16° W.
It seemed remarkable, and was very mortifying, to find the water at the head of the gulph as salt nearly as at the ship; nevertheless it was evident that much fresh water was thrown into it in wet seasons, especially from the eastern mountains. The summits of the ridge lie from three to four leagues back from the water-side, but the greater part of that space seemed to be low, marshy land. To the northward no hill was visible, and to the westward but one small elevation of flat-topped land; all else in those directions was mangroves and salt swamps, and they seemed to be very extensive.
Two miles below the place where the observations for the time-keeper were taken was a small cliff of reddish clay on the western shore; and being near it on our return, when the sun was approaching the meridian, I landed to observe the latitude. It was 32° 27' 56" south, so that the termination of the gulph may be called in 32° 24½' without making a greater error than half a mile. Mount Brown bore from thence S. 80½° E., and its latitude will therefore be 32° 30¼' south; the longitude deduced from bearings and the time-keepers on board is 138° 0¾' east.
Our return to the ship was a good deal retarded by going after the black swans and ducks amongst the flats. The swans were all able to fly, and would not allow themselves to be approached; but some ducks of two or three different species were shot, and also several sea pies or red bills. Another set of bearings was taken on the western shore, and at ten in the evening we reached the ship, where Mr. Brown and his party had not been long arrived. The ascent of Mount Brown had proved to be very difficult, besides having to walk fifteen miles on a winding course before reaching the foot; by perseverance, however, they gained the top at five on the first evening, but were reduced to passing the night without water; nor was any found until they had descended some distance on the following day. The view from the top of Mount Brown was very extensive, its elevation being not less than three thousand feet; but neither rivers nor lakes could be perceived, nor anything of the sea to the south-eastward. In almost every direction the eye traversed over an uninterruptedly flat, woody country; the sole exceptions being the ridge of mountains extending north and south, and the water of the gulph to the south-westward.
Mr. Brown found the stone of this ridge of craggy mountains to be argillaceous, similar to that of the flat-topped land where I had taken bearings on the west side of the inlet. It is reddish, smooth, close-grained, and rather heavy. Bushes and some small trees grown in the hollows of the rising hills; and between their feet and the mangrove swamps near the water there was some tolerably good though shallow soil.
We had seen fires upon the eastern shore opposite to Point Lowly on first entering the head of the gulph, and wherever I had landed there were traces of natives; Mr. Brown found them even to a considerable height up the side of the mountain; and it should therefore seem that the country here is as well inhabited as most parts of Terra Australis, but we had not the good fortune to meet with any of the people.
The observations taken by lieutenant Flinders fixed the position of the ship in latitude 32° 44' 41" south, and longitude by the time keepers 137° 49' 56" east. Twelve sets of distances of the sun and moon gave 137° 50' 9"; but these being all on one side, the time keepers are preferred. Azimuths observed from the binnacle, when the ship's head was between S. by E. and S. S. E., gave 0° 42' east, or 1° 37' east, nearly, for the true variation; and there was no particular attraction upon the theodolite at any of my stations on shore.
We had two flood tides in the day setting past the ship, and they ran at the strongest one mile and a half per hour; the rise appeared to be from six to eight feet, and high water to take place at two hours and a half after the moon passed the meridian. Except in the time of high water, which is considerably later than at Thorny Passage, the tides at the head have a near affinity to those at the entrance of the gulph; whence the great differences at Port Lincoln, intermediately situate, become so much the more extraordinary.
SATURDAY 13 MARCH 1802
Nothing of particular interest having presented itself to detain us at the head of the gulph, we got under way in the morning of the 13th, having a light breeze from the north-westward. The western shore had been followed in going up, and for that reason I proposed to keep close to the east side in returning; but before eight o'clock the water shoaled suddenly from 4 to 2 fathoms, and the ship hung upon a mud bank covered with grass, two or three miles from the shore. A kedge anchor was carried out astern; and in half an hour we again made sail downward, in soundings from 5 to 10 fathoms near the edge of the shoal.