Character of Ground.—­I have mentioned three distinct kinds of ground—­the earthy plains, the stony rises, and the sand ridges.  The latter, which is by far the most agreeable whether for travelling on, for feed, or in respect to the freedom from flies, ants, musquitoes, and rats, is simply a series of hills composed of blown sand of a red colour, very fine, and so compactly set that the foot does not sink in it much.  In some places the ridges have a uniform direction, in others the hills are scattered about without any regularity; the average direction of the ridges is north-north-east and south-south-west.  In the valleys between the hills, are shallow clay plains, in which the water rapidly collects, even after slight showers; but when full they seldom exceed five or six inches in depth, so that in summer they are soon dry again.

Stony Rises.—­The stony ground, in contradistinction to the sandstone ranges, appears to have been formed from the detritus of the latter, deposited in undulating beds of vast extent.  The greater portion of this ground appears almost level when one is on it, but when viewed from a distance the undulations are very distinct; the stones are chiefly water-worn pebbles of sandstone, quartz, and iron-stone; in some places the rises approach more nearly to the nature of the sandstone ranges, and here the stones are less water-worn, and are mixed with large blocks of rock.  I found the magnetic polarity to be very distinct in some of the ironstone pebbles on these rises.

Earthy Plains.—­The earthy plains which are such an important geological feature in this part of the country, will, I fear, greatly interfere with its future occupation.  When dry they are so intersected by chasms and cracks that it is in some places dangerous for animals to cross them, and when wet they would be quite impassable.  Cattle would, perhaps, do well on them for some time after an inundation, and the ground might improve after having been stocked.  The boggy nature of the banks of the creeks passing through this ground would be another impediment to settlers, from the losses of cattle that it would sometimes entail.  To furnish an idea of the danger in that respect, I may mention that there are places where, for a distance of two or three miles, neither a bullock nor a horse could get to the water with safety, and it was with difficulty that we could approach it ourselves; the safest spots are at the lower end of the waterhole, where the creeks run out on the plains.  A peculiar geological feature that I have never seen so strongly exhibited elsewhere is, that the watercourses on these plains have a strong tendency to work away to the south and south-west; the fall of the ground, as shown by the flow of the flood water, being to the west and north-west.  I found that at almost every place where a portion of the creek ran out, the small branches into which it split before disappearing, struck off at nearly right angles to