The breadth of the Sound, from Upper Head over to the inner end of Long Island, appeared to be three leagues, but it contracted upwards, and assumed the same river-like form as Shoalwater Bay; and it was to be feared, from the mangrove shores and muddiness of the water, that it would terminate in the same manner. No shoals could be then distinguished; but towards low water in the evening I again ascended the hill, and saw to my regret, that the upper parts were mostly occupied with banks of mud and sand, many of which were dry, and extended downward past the inner entrance of Thirsty Sound. Amongst the banks were various channels; but that of about two miles wide where the ship lay, was by far the most considerable. The small fifth opening, close on the west side of Upper Head, ran some miles in the low land towards the foot of a ridge of hills, lying three or four leagues at the back of the shore; but the greater part of this inlet was also taken up by mud banks, and the borders covered with mangroves. There was no fresh water at Upper Head, nor did I see any prospect of obtaining wherewith to complete the holds of the two vessels before leaving the coast; unless it were at a place a little higher up on the same side, to which the appearance of another opening between two hills, induced me to move the ship.
MONDAY 13 SEPTEMBER 1802
Next morning, when the flood made, we drifted upwards, with the Lady Nelson and a boat sounding ahead. After advancing three miles the brig suddenly took the ground, and we dropped a stream anchor; but in swinging to it, the ship was caught upon a bank of quick sand in eleven feet; and the tide running strong upon the broad side, it made her heel in a manner to excite alarm. The sails were immediately clewed down, and the top-gallant yards struck; and it appearing that the stream anchor allowed the ship to drive further up the bank as the tide rose, the best bower was let go, and then she righted and swung to the tide. The Lady Nelson also got off safe; but a part of the after sliding keel was carried away.
I went in a boat to examine the place which had presented the appearance of an opening; but it proved to be only a bending in the shore, and the mud banks and mangroves did not admit of landing; we therefore went back with the returning ebb to Upper Head, and moored the ship nearly in our first situation; where there was something more than 3 fathoms all round, at low water.
TUESDAY 14 SEPTEMBER 1802
On the following morning, the time keepers and other instruments were sent on shore under the charge of lieutenant Flinders, with two of the young gentlemen to assist him, and a guard of marines for the protection of the tents. It had appeared from the survey, that the time keepers were losing more than the Port-Jackson rates supposed; and before quitting this coast for the Gulph of Carpentaria, it was necessary to take fresh observations. Mr. Flinders undertook as usual to perform this service, whilst I should be absent up the Sound; and lieutenant Fowler was directed to examine and air all the stores, and make the ship ready for sea against my return.
Having made these dispositions, I embarked in the Lady Nelson with the naturalist, taking my whale boat and surveying instruments. We had a strong flood tide; and after grounding on a bank, anchored eleven miles above the ship, in 3 fathoms, that being the greatest depth to be found. It was then high water; and the brig being expected to be left dry by the ebb, we prepared for it by mooring, to prevent all chance of settling on the anchor, and hove up the fore and after keels; the new main keel being swelled by the wet, could not be raised, and when it took the ground, the vessel turned about violently and dragged both the anchors, until the keel broke off, and then she lay easy.
At low water, the seamen went out upon the dry flat and found the best bower cable parted, and the anchor so far buried in the quicksand, that it could not be raised. At ten o'clock the flood tide came rolling in, and presently set the brig afloat; the anchor was then weighed with ease, by means of a hawser previously bent to it, and the vessel rode by the small bower, against a tide which ran at the strongest between four and five knots.
WEDNESDAY 15 SEPTEMBER 1802
The Lady Nelson again took the ground at six in the morning. On sounding over to the east shore, distant half a mile, I found a small channel leading upwards, with four or five feet more water in it than where the brig lay; the western shore was two miles distant over a silty flat, which was dry at low water and level as a race ground.