was constructed.  We all felt comparatively at home here; and indeed we were really about halfway to our true home, for we had retraced about 300 miles and were not more than the same distance from Buree, which is only 170 miles from Sydney.  The cattle had done so well that I resolved to give them two days’ rest; and more could not be afforded them as the weather, though beautiful, might change, and we had some very soft ground still to go over.  It was remarkable that the water of the river, which for the last three days’ journey had been brackish, was here again, as formerly, as pure and sweet as any spring water.  Fort Bourke consists of an elevated plateau overlooking a reach of the river a mile and a half in length, the hill being situated near a sharp turn at the lower end of the reach.  At this turn a small dry watercourse, which surrounds Fort Bourke on all sides save that of the river, joins the Darling, and contains abundance of grass.

THE PLAINS.

The plateau consists of about 160 acres of rich loam, and was thinly wooded before it was entirely cleared by us in making our place of defence.  There are upon it various burying-places of the natives, who always choose the highest parts of that low country for the purpose of interment, their object being probably the security of the graves from floods.  The tribe frequenting that neighbourhood consists of a very few inoffensive individuals, less mischievous, as already observed, than any we had seen on the banks of the Darling.

SALTNESS OF THE DARLING.  THE RIVER SUPPORTED BY SPRINGS.

We were about to leave, at last, this extraordinary stream on which we had sojourned so long, enjoying abundance of excellent water in the heart of a desert country.  From the sparkling transparency of this water, its undiminished current, sustained without receiving any tributary throughout a course of 660 miles, and especially from its being salt in some places and fresh at others, it seems probable that the river, when in that reduced state, is chiefly supported by springs.  It would appear that the saltness occurs in the greatest body of water where no current was perceptible, and as this was excessive when the river was first discovered, it may be attributed to saline springs, due to beds of rock-salt in the sandstone or clay.  The bed of the river is on an average about sixty feet below the common surface of the country.  To this depth the soil generally consists of clay in which calcareous concretions and selenite occur abundantly; but at some parts the clay, charged with iron, forms a soft kind of rock in the bed or banks of the river.  There are no traces of watercourses on these level plains such as might be expected to fall from the hills behind; though the latter contain hollows and gullies, which must in wet seasons conduct water to the plains.  The distance of such heights from the river is seldom less than twelve miles; and it would appear that the intervening