to observe, that like most other
Australian rivers, it maintained a peculiar character throughout its
course, with great uniformity, even after it received tributaries
apparently larger than itself. All these lapsed into the same
concatenated line of ponds; at one place, spreading amidst brigalow
scrub, at another, forming one well-defined deep channel. For the
formation of ponds, and the retention of water, in so dry a climate, we
see here something between the ordinary character of rivers, and
artificial works which man must construct, when population may spread
into these regions. The fallen timber of the brigalow decays very slowly,
and is not liable to be burnt, like most other dead wood in open forests,
because no grass grows amongst the brigalow, as in open forests. The
accumulations of dead logs become clogged with river rack and the deposit
of floods; to which floods these heaps present obstructions, forcing the
waters into new channels, and, in their progress, scooping out new ponds,
and completing the embankment of dead logs; which thus form natural dams
and reservoirs to hold, under the shade of the brigalow trees, more water
for a longer time than any single river channel could retain, however
sluggish its course. Thus it was, that during a season of unusual
drought, we had found abundance in this river's course, across nearly 31/2
degrees of latitude. The fallen brigalow presents awkward obstructions to
wheel carriages; and, as the river spreads into broad plains, and is very
favourable to the growth of brigalow, the difficulty of travelling along
this river is greatest, where its waters are most scattered. Experience
has taught us, in such cases, to endeavour to follow the river channel as
closely as possible (the general course being very straight); and thus,
open grassy spots and small plains are frequently met with, beyond which
nothing could be distinguished, and from which it is safest to go forward
in the known general course of the chain of ponds. We again encamped
under Mount Mudge, where I perceived that a projecting portion of white
rock on the summit, had fallen since I had stood upon it; and that the
avalanche of rock had strewed the woody side of the mountain with white
fragments down to the very base. In the sheltered ravine below, a curious
new CASSIA formed a shrub six feet high.[*] Thermometer, at sunrise, 39 deg.;
at noon, 70 deg.; at 4 P.M., 82 deg.; at 9, 56 deg.;--with wet bulb, 50 deg..