The reef is in 15 degrees 57 minutes South, and 123 degrees 4 minutes 45 seconds East.
Six miles south of Caffarelli Island, is a rocky island, surrounded by a reef; and eight miles farther are several small rocky islands, forming the north extremity of a range, which, extending to the South by East for ten miles, form the eastern side of Sunday Strait, which is the best, and in fact the only safe communication with the deep opening between Point Cunningham and the islands to the eastward.

Between this strait and Point Swan, a distance of eleven miles, the space is occupied by a multitude of islands and islets, separated from each other by narrow and, probably, by deep channels, through which the tide rushes with frightful rapidity.
Sunday Strait is more than four miles wide, and appears to be free from danger.

The tide sets through it at the rate of four or five miles an hour, and forms strong ripplings, which would be, perhaps, dangerous for a boat to encounter.

The vessel was whirled round several times in passing through it; but a boat, by being able to pull, might in a great measure avoid passing through them.
CYGNET BAY is formed between the islands and Point Cunningham; it is fronted by a bank, over which the least water that we found was two fathoms; within this bank there is good anchorage, and near the inlets at the bottom of the bay, there is a muddy bottom, with eight and nine fathoms mud.
POINT CUNNINGHAM projects slightly to the eastward; its easternmost extremity is in latitude 16 degrees 39 minutes 20 seconds and longitude 123 degrees 10 minutes; from the northward it has the appearance of being an island, as the land to the westward is rather lower: two miles and a half south of it is Carlisle Head, the north extremity of GOODENOUGH BAY.
The shore thence extends in a South-South-East direction for seventeen miles, in which space there is a shoal bay, beyond which we did not penetrate.

Off the point is an islet, in latitude about 16 degrees 58 minutes, and to the south of it the land was seen trending to the South by East for four or five miles, when it was lost in distance.