April 17.--We travelled about nine miles N. 40 degrees W. On our way we passed a hill of baked sandstone, and several gullies. About five miles from our last camp, a large creek joined the river; beyond that creek, the country was, without exception, open, and rather of a more undulating character; the flats were somewhat rotten: the river became narrower, but was still running strong; and numerous ducks sported on its shady pools. April 18.--Last night we had a very cold north-easterly wind, and, during the day, some few drops of drizzling rain. We travelled about N. by W. to latitude 19 degrees 18 minutes 16 seconds. After passing some gullies, we came into a more broken and hilly country; the river formed here a large anabranch. The Ironbark trees, which timbered the extensive flat along the river, became much finer; but the soil was rotten: the poplar-gum grew on the stiff soil of the hollows. About six miles from our last camp, we came to ranges of high hills of a conical form, and with rounded tops, striking from west to east, and then entered a narrow valley, bounded on each side by rocky hills. Mr. Roper observed a rugged country to the northward, and a fine high range to the south-east. The whole country from the large flat to our camp, was composed of felspathic porphyry, containing crystals of felspar, and accidentally of quartz, in a paste varying in colour and hardness. In the bed of the river, I still found pebbles of pegmatite, granite, quartz, and basalt; indicating that a country of varied character was before us. The stream wound its way from one side of the broad sandy bed to the other; and those parts where it flowed, were generally very steep, and covered with a dense vegetation, whilst, on the opposite side, the banks sloped gently into the broad sands. Among the shrubs and grasses, a downy Abutelon was easily distinguished by its large bright yellow blossoms. My Blackfellows procured several messes of ducks; and Brown brought me a piece of indurated clay with impressions of water-plants.