On the 27th we continued onwards, obliged to keep the course by taking bearings on any prominent though trifling object in front. At ten miles there was a sensible fall of some few feet from the level of the Stony Desert, as I shall henceforth call it, and we descended into a belt of polygonum of about two miles in breadth, that separated it from another feature, apparently of equal extent but of very different character. This was an earthy plain, on which likewise there was no vegetation; resembling in appearance a boundless piece of ploughed land, on which floods had settled and subsided--the earth seemed to have once been mud and then dried. It had been impossible to ascertain the fall or dip of the Stony Desert, but somewhat to the west of our course on the earthy plain there were numerous channels, which as we advanced seemed to be making to a common centre towards the N.E. Here and there a polygonum bush was growing on the edge of the channels; and some of them contained the muddy dregs of what had been pools of water. Over this field of earth we continued to advance almost all day, without knowing whether we were getting still farther into it, or working our way out. About an hour before sunset, this point was settled beyond doubt, by the sudden appearance of some hills over the line of the horizon, raised above their true position by refraction. They bore somewhat to the westward of north, but were too distant for speculation upon their character. It was very clear, however, that there was a termination to the otherwise apparently boundless level on which we were, in that direction, if not in any other. Our view of these hills was but transient, for they gradually faded from sight, and in less than ten minutes had entirely disappeared. Shortly afterwards some trees were seen in front, directly in the line of our course; but, as they were at a great distance, it was near sunset before we reached them; and finding they were growing close to a small channel (of which there were many traversing the plain) containing a little water, we pulled up at them for the night, more especially as just at the same moment the hills, before seen, again became visible, now bearing due north. To scramble up into the box-trees and examine them with our telescopes was but the work of a moment, still it was doubtful whether they were rock or sand. There were dark shadows on their faces, as if produced by cliffs, and anxiously did we look at them so long as they continued above the horizon, but again they disappeared and left us in perplexity. They were, however, much more distinct on the second occasion, and Mr. Browne made out a line of trees, and what he thought was grass on our side of them.
There was not a blade of anything for our horses to eat round about our solitary bivouac, so that we were obliged to fasten them to the trees, only three in number, and to the cart. There was, however, a dark kind of weed growing in the creek, and some half dozen stalks of a white mallow, the latter of which Flood pulled up and gave to the horses, but they partook sparingly of them, and kept gnawing at the bark of the trees all night long.
In reference to our movements on the morrow, it became a matter of imperative necessity to get the poor things to where they could procure some food as soon as possible; I determined, therefore, to make for the hills, whatever they might be, at early dawn. The night was exceedingly cold, the thermometer falling to freezing point. At day-break there was a heavy fog, so we did not mount until half-past six, when the atmosphere was clearer, the fog having in some measure dispersed. We then proceeded, and for the first time since commencing the journey turned from the course 332 degrees, or one of N.N.W. to one due north, allowing 5 degrees for easterly variation. My object was to gain the trees Mr. Browne had noticed, as soon as possible, but did not reach them until a quarter to ten. We then discovered that they lined a long muddy channel, in which was a good deal of water, but not a blade of vegetation anywhere to be seen. I turned back, therefore, to a small sandy rise, whereon we had observed a few tufts of grass, and allowed the animals to pick what they could. At this spot we were about a mile and a half from the hills, which now stood before us, their character fully developed, and whatever hope we might have before encouraged of the probability of a change of country on this side of the desert, was at one glance dispelled. Had these hills been as barren as the wastes over which we had just passed, so as they had been of stone we should have hailed them with joy. But, no!--sandy ridges once more rose up in terrible array against us, although we had left the last full 50 miles behind, even the animals I think regarded them with dismay.
From the little rising ground on which we had stopped, we passed to the opposite side of the creek, which apparently fell to the east, and traversing a bare earthy plain, we soon afterwards found ourselves ascending one of the very hills we had been examining with so much anxiety through a glass the evening before. It was flanked on either side by other hills, that projected into and terminated on this plain, as those we had before seen terminated in the Stony Desert; and they looked, as I believe I have already remarked, like channel head-lands jutting into the sea, and gradually shutting each other out. The one we ascended was partly composed of clay and partly of sand; but the former, protruding in large masses, caused deep shadows to fall on the faces and gave the appearance of a rocky cliff to the whole formation, as viewed from a distance.
Broad and striking as were the features of the landscape over which the eye wandered from the summit of this hill, I have much difficulty in describing them.
Immediately beneath was the low region from which we had just ascended, occupying the line of the horizon from the north-east point, southwards, round to the west. Southward, and for some degrees on either side, a fine dark line met the sky; but to the north-east and south-west was a boundless extent of earthy plain. Here and there a solitary clump of trees appeared, and on the plain, at the distance of a mile to the eastward, were two moving specks, in the shape of native women gathering roots, but they saw us not, neither did we disturb them,--their presence indicated that even these gloomy and forbidding regions were not altogether uninhabited.
As the reader will, I have no doubt, remember, the sandy ridges on the S.E. side of the Desert were running at an angle of about 18 degrees to the west of north, having gradually changed from the original direction of about 6 degrees to the eastward of that point. I myself had marked this gradual change with great interest, because it was strongly corroborative of my views as to the course the current I have supposed to have swept over the central parts of the continent must have taken, i. e. a course at right angles to the ridges. It is a remarkable fact that here, on the northern side of the Desert, and after an open interval of more than 50 miles, the same sand ridges should occur, running in parallel lines at the same angle as before, into the very heart of the interior, as if they absolutely were never to terminate. Here, on both sides of us, to the eastward and to the westward, they followed each other like the waves of the sea in endless succession, suddenly terminating as I have already observed on the vast plain into which they ran. What, I will ask, was I to conclude from these facts?--that the winds had formed these remarkable accumulations of sand, as straight as an arrow lying on the ground without a break in them for more than ninety miles at a stretch, and which we had already followed up for hundreds of miles, that is to say across six degrees of latitude? No! winds may indeed have assisted in shaping their outlines, but I cannot think, that these constituted the originating cause of their formation. They exhibit a regularity that water alone could have given, and to water, I believe, they plainly owe their first existence. It struck me then, and calmer reflection confirms the impression, that the whole of the low interior I had traversed was formerly a sea-bed, since raised from its sub-marine position by natural though hidden causes; that when this process of elevation so changed the state of things, as to make a continuous continent of that, which had been an archipelago of islands, a current would have passed across the central parts of it, the direction of which must have been parallel to the sandy ridges, and consequently from east to west, or nearly so--that also being the present dip of the interior, as I shall elsewhere prove. I further think, that the line of the Stony Desert being the lowest part of the interior, the current must there have swept along it with greater force, and have either made the breach in the sandy ridges now occupied by it, or have prevented their formation at the time when, under more favourable circumstances, they were thrown up on either side of it. I do not know if I am sufficiently clear in explanation, finding it difficult to lay down on paper all that crowds my own mind on this subject; neither can I, without destroying the interest my narrative may possess, now bring forward the arguments that gradually developed themselves in support of the foregoing hypothesis.
Although I had been unable to penetrate to the north-west of Lake Torrens, that basin appeared to me to have once formed part of the back waters of Spencer's Gulf; still I long kept in view the possibility of its being connected with some more central body of water. Having however gained a position so much higher to the north, and almost on the same meridian, and having crossed so remarkable a feature as the Stony Desert (which, as I suppose, was once the focus of a mighty current, to judge from its direction passing to the westward), I no longer encouraged hopes which, if realized, would have been of great advantage to me, or regretted the circumstances by which I was prevented from more fully examining the north-east and northern shores of Lake Torrens. I felt doubtful of the immediate proximity of an inland sea, although many circumstances combined to strengthen the impression on my mind that such a feature existed on the very ground over which we had made our way. I had assuredly put great credit on the statements of the solitary old man who visited the Depot, but his information as far as we could judge had turned out to be false; and I was half angry with myself for having been so credulous, well aware as I was of the exaggerations of the natives, and how little dependence can be placed on what they say.