The northern entrance to Port Curtis is accessible only to boats; but ships of any size may enter the port by the southern opening. Mr. Murray did not find any passage on the south side of the shoal near Gatcombe Head, but could not say that none existed; he thought the deep channel to be not more than a mile wide; but at half a mile from the head there was from 6 to 10 fathoms, and the channel from thence leads fair up the port to beyond South-trees Point; I suspected, however, from the account given by Mr. Murray, that there might be a second shoal, lying not so much as a mile from the head, and one is marked in the plan accordingly, that ships may be induced to greater caution. There is good anchorage just within Gatcombe Head; and at a small beach there, behind a rock, is a rill of fresh water, and wood is easily to be procured. I cannot venture to give any other sailing directions for going up this port, than to run cautiously, with a boat ahead and the plan upon the binnacle. Both the bottom and shoals are usually a mixture of sand, with mud or clay; but in the northern entrance, and off some of the upper points and islands where the tides run strong, the ground is in general rocky. The country round Port Curtis is overspread with grass, and produces the _eucalyptus_ and other trees common to this coast; yet the soil is either sandy or covered with loose stones, and generally incapable of cultivation. Much of the shores and the low islands are overspread with mangroves, of three different species; but that which sends down roots, or rather supporters from the branches, and interweaves so closely as to be almost impenetrable, was the most common. This species, the _Rhizophora Mangle_ of Linnaeus, is also the most abundant in the East and West Indies; but is not found at Port Jackson, nor upon the south coast of this country. Granite, streaked red and black, and cracked in all directions, appeared to be the common stone in the upper parts of the port; but a stratified argillaceous stone was not unfrequent; and upon the larger island, lying off the point of Hill View, there was a softish, white earth, which I took to be calcareous until it was tried with acids, and did not produce any effervescence.