June 7.--The same difficult country not only continued, but rather increased. Charley told me last night, on his return from a walk, that he had found sandstone. To-day we travelled over porphyries like those of the last stage: but, about four miles from the last camp, steep sandstone rocks with excavations appeared on our left, at some distance from the river, from which they were separated by porphyry; but, farther on, they approached the river on both sides, and formed steep slopes, which compelled us to travel along the bed of the river itself. Two large creeks joined the river from the southward, one of which was running, and also made the river run until the stream lost itself in the sandy bed. At the end of the stage, however, the stream re-appeared, and we were fairly on the fourth flowing river of the expedition: for the Condamine, although not constantly, was raised by rains, and showed the origin of its supply, by the muddy nature of its waters; the Dawson commenced running where we left it; and the Burdekin, with several of its tributaries, was running as far as we followed it. The waters of the Dawson, the Burdekin, and the Lynd, were very clear, and received their constant supply from springs. We passed a camp of natives, who vere very much alarmed at the report of a gun, which Mr. Gilbert happened to fire when very near them; this he did in his anxiety to procure a pair of Geophaps plumifera, for his collection. These pretty little pigeons had been first observed by Brown in the course of our yesterday's stage, who shot two of them, but they were too much mutilated to make good specimens. We frequently saw them afterwards, but never more than two, four, or six together, running with great rapidity and with elevated crest over the ground, and preferring the shady rocks along the sandy bed of the river. I tried several methods to render the potatoes, which we had found in the camps of the natives, eatable; but neither roasting nor boiling destroyed their sickening bitterness. At last, I pounded and washed them, and procured their starch, which was entirely tasteless, but thickened rapidly in hot water, like arrow-root; and was very agreeable to eat, wanting only the addition of sugar to make it delicious; at least so we fancied. June 8.--We travelled about nine miles west-north-west. The country was in general open, with soft ground on the more extensive flats; although sandstone ranges approached the river in many places. Four good-sized creeks entered the river from the southward. The sandstone, or psammite, was composed of large grains of quartz mixed with clay of a whitish red or yellow colour; it frequently formed steep cliffs and craggy rugged little peaks. The stringy-bark grew to a fine size on the hills, and would yield, together with Ironbark and the drooping tea-tree, the necessary timber for building. A new species of Melaleuca and also of Boronia were found, when entering upon the sandstone formation.