Next afternoon, I went, accompanied by the naturalist, to examine the eastern arm of the bay, which is divided into two branches. Pursuing the easternmost and largest, with soundings from 6 to 3 fathoms, we came to several mangrove islands, about four miles up, where the stream changed its direction from S. S. E. to E. S. E., and the deepest water was 2 fathoms. A little further on we landed for the night, cutting a path through the mangroves to a higher part of the northern shore; but the swarms of musketoes and sand flies made sleeping impossible to all except one of the boat's crew, who was so enviably constituted, that these insects either did not attack him, or could not penetrate his skin. It was high water here at nine o'clock; and the tide afterwards fell between ten and twelve feet. FRIDAY 13 AUGUST 1802 In the morning, I set Broad Mount in Keppel Bay at N. 61° 20' W. and Mount Larcom S. 8° 20' E; and we then steered onward in six to eight feet water, amongst various little islands of mud and mangroves; the whole width of the stream being still more than half a mile, nearly the same as at the entrance. Three miles above the sleeping place the water began to increase in breadth, and was 2 fathoms deep; and advancing further, it took a direction more southward, and to our very agreeable surprise, brought us to the head of Port Curtis; forming thus a channel of communication from Keppel Bay, and cutting off Cape Capricorn with a piece of land twenty-five miles in length, from the continent. I landed on the eastern shore, nearly opposite to the reddish cliffs which had been my uppermost station from Port Curtis, and set Broad Mount in Keppel Bay at N. 60° 45' W. Mount Larcom, S. 16 15 W. Having found one communication, we rowed up the western branch near the reddish cliffs, hoping to get back to Keppel Bay by a second new passage; but after going two miles, with a diminishing depth from 4 fathoms to three feet, we were stopped by mangroves, and obliged to return to the main stream. The tide was half ebbed when we came to the shallowest part of the communicating channel; and it was with much difficulty that the boat could be got over. A space here of about two miles in length, appears to be dry, or very nearly so, at low water; but it is possible that some small channel may exist amongst the mangroves, of sufficient depth for a boat to pass at all times of tide.