The grass near the camp having been burnt off, the horses had scattered very much, and could not be collected and saddled before 10.0 a.m., when we followed our track of yesterday and reached the pool of water at sunset. The country was so level, although we were crossing the watershed between the north-west coast and the Gulf of Carpentaria, that the aneroid only varied from 29.55 to 29.62, and even of this change the greater part was caused by alteration of the temperature. The geological character of this portion of the country differs slightly from that of the Victoria River. The upper stratum is a bed of ironstone conglomerate about twenty feet thick, this rests on sandstone, the upper part of which is highly ferruginous, then passes away into a variegated sandstone imperfectly stratified, changing into a hard siliceous sandstone which is white and breaks with a conchoidal fracture; this rests on a hard cherty sandstone similar to that of the Victoria River. In this rock many depressions occur, which is apparently caused by the roofs of caverns falling in and there are usually deep fissures in the rock at the bottom of these hollows, in which all the water that drains into them is absorbed; in some places the sandstone resting on the limestone has sunk many feet below the general level, with areas varying from one to ten acres, sometimes sloping towards a centre ten to thirty feet below the plain, and in other spots with abrupt rocky banks five to eight feet high and a perfectly level bottom. The level character of the country is unfavourable for investigations of this nature, and the thickness of the several strata not easily determined; but I think that the collective thickness of the several strata above the limestone does not exceed 100 feet. The porous nature of the lower rocks preclude the existence of permanent surface water by draining the whole of the upper part of the tableland, while it forms strong springs in the lower ground towards the banks of the Roper River, where the limestone is exposed on the surface. Latitude by a Coronae Borealis 15 degrees 14 minutes 31 seconds. WHITE MAN'S CAMP. 13th July (Sunday).