by it last year: it was then
thought to be about forty feet, but I now found it could not be less than
one hundred and fifty. The rock, a fine-grained siliceous sandstone, is
disposed in horizontal strata, from six to twelve feet thick, each of
which projects about three feet from that above it, and forms a
continuity of steps to the summit, which we found some difficulty in
climbing; but where the distance between the ledges was great we assisted
our ascent by tufts of grass firmly rooted in the luxuriant moss that
grew abundantly about the water-courses. On reaching the summit, I found
that the fall was supplied from a stream winding through rugged chasms
and thickly-matted clusters of plants and trees, among which the pandanus
bore a conspicuous appearance and gave a picturesque richness to the
place. While admiring the wildness of the scene, Mr. Montgomery joined
me; we did not however succeed in following the stream for more than a
hundred yards, for at that distance its windings were so confused among
rocks and spinifex that we could not trace its source. After collecting
for Mr. Cunningham, who was confined on board by sickness, a few
specimens of those plants which, to me, appeared the most novel, we
commenced our descent, and reached the bottom in safety; by which time
the tide was ebbing so rapidly that we set off immediately on our return
with a view of arriving on board by low-water, in order that no time
might be lost in sending the boats up with our empty water-casks.

During our absence Mr. Roe, who was fast recovering from the effects of
his fall, had obtained the sun's meridional altitude upon the islet at
the entrance of the river, which gave 15 degrees 25 minutes 46 seconds
for its latitude, differing from the plan of last year by only fifteen
seconds.

July 27.

The following day the boats were despatched up the river, but as the
ebb-tide ran until after four o'clock it was late at night before they
reached the cascade, having experienced some delay by running upon the
sandbanks, which, above Alligator Island, are very numerous and form a
narrow winding channel of not more than twelve feet deep; these banks are
dry at low-water, and are composed of a yellow quartzose sand. At
midnight, as soon as the launch and cutter were loaded, for it did not
take more than half an hour to fill the casks, I despatched them to the
vessel with orders to return the following night for another load, and in
the mea