My impression, when travelling the country to the west and N.W. of the marshes of the Macquarie, was, that I was traversing a country of comparatively recent formation. The sandy nature of its soil, the great want of vegetable decay, the salsolaceous character of its plants, the appearance of its isolated hills and flooded tracts, and its trifling elevations above the sea, severally contributed to strengthen these impressions on my mind. My knowledge of the interior is, however, too limited to justify me in any conclusion with regard to the central parts of Australia. An ample field is open to enterprise and to ambition, and it is to be hoped that some more decisive measures will be carried into effect, both for the sake of the colony and of geography, to fill up the blank upon the face of the chart of Australia, and remove from us the reproach of indifference and inaction. BARBER'S STATEMENT. Since the above pages were written, an expedition was undertaken by Major Mitchell, the Surveyor-General, to ascertain the truth of a report brought in by a runaway convict of the name of Barber, or Clarke, who had been at large for five years, at different times, among the natives to the northward of Port Macquarie. This man stated that a large river, originating in the high lands near Liverpool Plains, and the mountains to the north of them, pursued a N.W. course to the sea. His story ran thus: Having learnt from the natives the existence of this river, he determined to follow it down, in hopes that he might ultimately be enabled to make his escape from the colony. He accordingly started from Liverpool Plains, and kept on a river called the Gnamoi, for some time, which took him N.W. After a few days' journey, he left this river, traversed the country northwards, and crossed some lofty ranges. Descending to the N.E. he came to another large river, the Keindur, which again took him N.W. He travelled 400 miles down it, when he observed a large stream joining it upon its left bank, which he supposed to be the Gnamoi. The river he was upon was broad and navigable. It flowed through a level country with a dead current and muddy water, and spread into frequent lakes. He found that it ultimately discharged itself into the sea, but was uncertain at what distance from its sources. He was positive he never travelled to the SOUTHWARD OF WEST. He ascended a hill near the sea, and observed an island in the distance, from which, the natives informed him, a race of light-coloured men came in large canoes for a scented wood; but having failed in the immediate object of his journey, he was eventually obliged to return. MAJOR MITCHELL'S REPORT.