16TH APRIL.--In order better to contend with the difficulty of wanting water, and be better prepared for it, I formed my party rather of infantry than cavalry, taking only two horses, drawing a cart loaded chiefly with water, and six trusty men, almost all old soldiers. We were thus prepared to pass several nights without requiring other water than that we carried with us. I hoped thus to be enabled to penetrate the scrubs, and reach, and perhaps cross, the higher land bounding this great basin. Our first day's progress, being rather experimental, did not extend above ten miles. I had been obliged to send back the shaft horse, and exchange him for a better, as our load of water was heavy. The day was very sultry. Thermometer 105 deg. Fahrenheit, in the shade. We had passed over ground more open than I expected, but by no means clear of scrubs. Thermometer, at sunrise, 64 deg.; at 4 P. M., 105 deg.; at 9, 71 deg.;--with wet bulb, 67 deg.. 17TH APRIL.--The messenger returned early with two horses, one being my own second charger, which I put as leader to the cart. We then got forward on foot as fast as the men could walk, or rather as fast as they could clear a way for the cart. We passed through much scrub, but none was of the very worst sort. The natives' marks on trees were numerous, and the ground seemed at first to fall westward as to some water-course; and, after travelling about five miles, there appeared a similar indication of water to the eastward of our route. At one place even the white-barked gum trees appeared; but, although they had the character of river trees, we found they grew on an elevated piece of clay soil. After completing about ten miles, I halted for two hours to rest the horses, where there was a patch of good grass, and we gave them some water from our stock. The mercurial column afforded no indication that we were at all higher than our camp overlooking the river, and it seemed, therefore, not improbable that we might meet with some other channel or branch of that prolific river. After resting two hours we continued, passing through woods partly of open forest trees, and partly composed of scrub. Towards the end of our day's journey, we crossed land covered with good grass, and having only large trees on it, so thinly strewed as to be of the character of the most open kind of forest land. Saw thereon some very large kangaroos, and throughout the day we had found their tracks numerous. We finally set up our bivouac a little before sunset, on a grassy spot surrounded by scrub. In this scrub I found the CLEOME FLAVA of Banks, and the strong-smelling AMBRINA CARINATA. A very remarkable whiteness appeared on the leaves of the EUCALYPTUS POPULIFOLIUS, which, on very close examination, appeared to be the work of an insect.[*] On the plains the SALSOLA AUSTRALIS formed a round bush, which, when loose from its very slight root, was liable to be blown about. Thermometer at sunrise, 71 deg.; at 9 P.