You may pass on either side, but the south side is fairest for going up the south-west arm; keep mid-channel between the island and south shore: this shore is so bold that you may run within two cables length of it. In your way up you will perceive a branch on the north side, which runs up north-west; when thus high, you are above a bank or middle ground, on which the least water is 16 feet; you may, by keeping near the shore, pass on either side of this shoal, which has gradual soundings to it; the south side has most room and deepest water; the north side has five fathoms: when above this, you may keep in the middle, if you wish to go higher, and the least water will be five or six fathoms for several miles higher: from this south-west arm several branches extend, most of which have good depth of water, but the chart will be the best guide.
If you wish to enter the north-west branch, enter it by keeping the larboard shore on board, and for some distance up, as from the starboard shore a shoal extends one-third of the distance over.
After having rested a few days, I determined not to lose any time, but go immediately and make a survey of Botany-Bay, while the weather was cool and pleasant.
Towards the end of September, two boats with provisions, tents, &c. were got ready, and dispatched round, under the care of Mr. Keltie, the master of the Sirius, by whom, and Mr. Blackburn, the master of the Supply, I was assisted in my work at Botany-Bay. A few gentlemen of the settlement having signified a wish to accompany me, the party resolved to walk over and meet the boats there; this route being now well known, and the path well trodden, it was not an unpleasant walk. We joined the boats about noon, and found our tents pitched.
The same afternoon we began our operations, and in about ten days had finished the survey of the bay. The anchorage in this bay, as I have before observed, is extensive, and the passage into it easy; there is a cluster of rocks, which lie south-south-east, about two cables length from a little bare island on the north shore, on which the sea frequently breaks very high; but if you keep Cape Banks open, you will avoid them; both shores are bold to, till you come thus high. A little above Point Southerland (south shore) is another patch of rocks, which, to avoid in turning, keep the land below this point open. Although the anchorage here is extensive, yet by looking at the chart, it will appear a small spot for so very large a piece of water: from both the north and south sides, and from the bottom of the bay, the flats run off a great distance, from four to fifteen feet water.
I did formerly believe, that there was an easy channel over the flats into the west river, but on this examination I think it rather difficult, if practicable at all, as the soundings are very irregular.
This river in some parts has good depth, and that near and within its entrance; but higher up it is all shoal water, and full of knowls of sand; in short, it is only to be navigated by boats: it has two branches, in which there are several coves, or bays, containing shoal water.
After having gone to the head of this river, and returned to the bay again, we then entered a small river which empties itself in the north-west part of the bay; this river, as far as I went up, which was about five miles, is all shoal water (it has since been examined to the head by Lieutenant Bradley): in short, these rivers were with me no object at this time to throw away time upon; I therefore made no other survey than an eye sketch; every reach is laid down true with respect to direction; the soundings are the depth at or near low water; and the distance is estimated by short portions at a time, that they might be the more correct.
It will easily be perceived, by looking at the draft of this bay, that it is not possible to lie land locked with a ship in any part of it; you will always be exposed to the large sea which tumbles in here with an easterly wind. The edge of the flatts (in three fathoms) is determined by many intersections, so that its extent is pretty nearly ascertained.
In the end of October it was judged necessary to shorten the allowance of provisions one-third; for although we might expect store-ships from England by the end of January, 1790, yet as there did not remain above five months provisions in the settlement, the governor thought it necessary to issue an order for two-thirds allowance to commence the 1st of November.