The Medusa Bank fronts the entrance of Cambridge Gulf; it projects from the coast, near Cape Domett, to the North-West for seventeen miles, and terminates with a narrow spit, thirteen miles north from Lacrosse Island, in latitude 14 degrees 30 1/2 minutes. Both these banks are of sand, and their edges are very steep to. They are covered with large quantities of mollusca, which are also abundant in the sea in their vicinity. CAMBRIDGE GULF extends from Lacrosse Island in a South-South-Westerly direction for sixty-four miles. The entrance, between Cape Domett and Cape Dussejour, is twelve miles wide; but Lacrosse Island, under which there is good anchorage for vessels going in or out of the gulf, divides the entrance into two channels. The western entrance is about two miles and a half wide, and is deepest near the island: but, at a mile from the shore, we had no bottom with fourteen and seventeen fathoms. The reefs project from Cape Dussejour for nearly three miles. On the eastern side of Lacrosse Island, within half a mile of the point, we had seven fathoms, and there was every appearance of the channel being deep in the neighbourhood of Cape Domett. Shakspeare Hill, the situation of which is in latitude 14 degrees 47 minutes 55 seconds, and longitude 128 degrees 24 minutes, is a conspicuous object on this promontory: it is high and rocky, and, at a distance, has the appearance of being insulated, like Lacrosse Island. Having entered the gulf, it trends to the South-South-West for twenty-three miles to Adolphus Island, where it is divided into two arms, of which the westernmost is the principal. At ten miles from Lacrosse Island, the channel is narrowed by shoals to a width of five miles, the shores being twelve miles apart. The land on the western side of the gulf is high and rocky; but the opposite shore is very low, and apparently marshy. The bottom is of sand, as are the banks on either side, and affords good anchorage: the tide stream runs with great strength in mid-channel, but is easily avoided by anchoring upon the weather shore near the edge of the bank.