disappearing, and giving place to the salt-water tea-tree. By nightfall,
I was unable to proceed any further, owing to the large stones and rocks
that interposed themselves. Retracing my steps, therefore, for a mile or
two, to a little grass I had observed as I passed by, I bivouacked for
the night, being, as well as the horses, quite knocked up. The native
boy, who accompanied me, was equally fatigued; and we were both lame from
walking across so rugged a country, over a great portion of which we
found it quite impracticable to ride. Our stage could not have been less
than twenty-five or twenty-six miles during the day, yet we had not met
with a drop of water, even though we had high ranges, large watercourses,
and huge gum-trees on every side of us. As usual, the traces of high
floods were numerous; and the channels of these watercourses, confined as
they are by precipitous ranges, must, at times, be filled by rapid and
overwhelming torrents, which would collect there after heavy rains.

Some great progressive change appears to be taking place in the climate
and seasons of this part of the country, as, in many of the watercourses,
we found all the gum-trees either dying or dead, without any young trees
growing up to replace them. The moisture which had promoted their growth,
and brought them to maturity, existed no longer; and in many places, only
the wreck of noble trees remained to indicate to the traveller what once
had been the character of this now arid region. In other watercourses the
gum-trees were still green and flourishing, and of giant growth; but we
were equally unable to discover water in these,[Note 5: We had no means
with us of digging--possibly moisture existed below the surface where the
trees were so large and green.] as in those where the trees were decaying
or withered.

July 17.--To-day we returned to our temporary camp, tracing up various
branches of the water-courses as we went along, but without finding
water. Many of the ranges in our route consisted of masses of ironstone,
apparently containing a very large proportion of metal. In one place, I
found a mineral which I took to be tin ore; the loss, however, of all the
geological specimens I collected, after their arrival in Adelaide, has
unfortunately put it now beyond my power to test any of the rocks or
minerals, about which I was doubtful. As we encamped early, and I was
desirous of recruiting the horses, I employed myself in taking an
obs