The greater part of to-day was spent in making a more minute examination of the bay, the shoal discovered yesterday rendering a more careful search necessary. From the summit of Point Cunningham, I had a fine view of the opposite shore of the sound; very broken and rugged it appeared to be. To the South-East and south I could see no land; a circumstance which raised my hopes of finding in that direction the long and anxiously expected river, which the geological formation of the country, and all the recorded experience of discovery, alike warranted us in anticipating. The point upon which I stood was a steep and cliffy rock facing the sea, connected with the mainland by a low and narrow neck of land, but almost insulated at high-water during the spring tides. A singular cliff, projecting on its South-East side, is called by Captain King, Carlisle Head; but we searched in vain for the fresh water, which that distinguished navigator speaks of, as having been found there by him in 1819. SINGULAR VITREOUS FORMATION. We remarked here, certain vitreous formations, in all, except form, identical with those already described as having been seen at Point Swan. These were small balls lying loose on the sandy beach, at the bottom of the cliff; they were highly glazed upon the surface, hollow inside, and varying in size from a musket, to a tennis ball.* (*Footnote. Vide Mr. Darwin on "superficial ferrugineous beds" Geology of Volcanic Islands page 143.) February 23. We weighed early in the morning, and rounded Point Cunningham; anchoring again at 10 o'clock A.M., 8 miles north of it, in 7 fathoms (low-water); West by North, one mile from where we lay, a red cliffy head, called by Captain King, in memory of the difficulties which ultimately compelled him to leave this interesting coast, Foul Point, marks the limit of his survey of this part of the northern shore of Australia, and terminates the range of cliffs,* which, up to this point, forms nature's barrier against the sea. Beyond it, the coast assumes a low and treacherous character, and subsides into a deep bay, called by Captain King, not without reason, Disaster Bay. (*Footnote. The cliffs at Foul Point and Point Cunningham unite the sandstone and argillaceous formation.) From the masthead, from whence I hoped to get a wide view of the unknown waters we were about to explore, I could just see Valentine Island, bearing South-South-East about 17 miles. Its lofty extremities alone being visible, it had the appearance of two islands. Here, then, a really most interesting--nay, a most exciting--portion of the duties of the survey were to commence in earnest; and it was reserved for us to take up the thread of discovery reluctantly abandoned by our enterprising and scientific predecessor, at the moment when the prize was almost within his grasp. EXPLORING PARTY IN BOATS.