While standing towards a small island bearing North and by West five and a half miles from Point Adieu, we discovered a single rock with apparently deep water all around it, and just awash at low-water. It bore North-West and by West three-quarters of a mile from this island, which resembles Red Island, and Captain King's group of the Rocky Islands, in that calcined-like appearance which has by turns given them red and brown for a distinct appellation. In the afternoon we saw the sandbank laid down in Captain King's chart; it appeared a white rocky islet. The night was spent beating to the westward, between it and Red Island, against a light breeze. April 20. At daylight, whilst standing to the South-West the water shoaled rapidly though regularly from 20 to 6 fathoms, we then tacked, Red Island bearing South-East one mile and a quarter; in standing out (north) the water deepened suddenly and almost immediately to 15 fathoms. I imagine this shoal to be a continuation of one laid down by Captain King, extending two miles south from Red Island: passing the latter on our way to Port George the Fourth we had 28 to 30 fathoms, two and a half miles from its North-West side. April 21. We continued to make but little progress to the westward, scarcely averaging more than a mile per hour: the soundings indicating that we were still on the coral ledge that skirts the whole of this coast, northward of Cape Leveque; on the raised parts of which are numerous reefs of an irregular size and almost invariably trending from West to North-West. The number of these low coral reefs already known, and the probable number of those yet undiscovered, make this rather a dangerous sea, and must have a tendency to lessen the value of the North-West coast of Australia for purposes of forming settlements. In the afternoon we saw again the reef discovered and named after the Beagle. Steering West-North-West we passed four miles from its northern side in soundings varying from 41 to 47 fathoms. REMARKABLE RIPPLINGS. April 23. Towards the close of this day we passed through a line of very remarkable ripplings, extending in a north and south direction, which we knew indicated some great inequality in the bottom, but whether from deep to shoal water was a matter of some anxiety; therefore, with leadsmen in the chains and the men at their stations for working ship, we glided into this streak of agitated water, where plunging once or twice she again passed into the silent deep. We sounded ineffectually with 86 fathoms in the ripplings; for some time before the soundings had been regular 52 and 55 fathoms fine sand, and four miles beyond it we had 146 fathoms, but did not succeed afterwards in reaching the bottom with 200 fathoms. This line of disturbed water, therefore, marks the edge of the bank of soundings fronting this part of the coast, from which the nearest point, Cape Leveque, bore South-East 195 miles. PART FROM THE LYNHER.