Expedition into Central Australia | Page 4

I am a lover of it; and to my own exertions, during past years of military repose, I owe the little knowledge I possess of those branches of it, which have since been so useful to me.
It will not be deemed presumptuous in me, I trust, to express a belief that the majority of my readers will find much to interest them in the perusal of this work; which I publish for several reasons--firstly, in the hope, that a knowledge of the extremities to which I was driven, and of the unusual expedients to which I was obliged to resort, in order to save myself and my companions from perishing, may benefit those who shall hereafter follow my example; secondly, that as I published an account of my former services, my failing to do so in the present instance might be taken as evidence that I lacked the moral firmness which enables men to meet both success and defeat with equal self-possession; and thirdly, because, I think the public has a right to demand information from those, who, like myself, have been employed in the advancement of geographical knowledge. I propose, therefore, to devote my preliminary chapter to a short review of previous Expeditions of Discovery on the Australian continent, and so to lay down its internal features, that my friends shall not lose their way.
I propose, also, to give an account of the state of South Australia when I left it in May last, for, as the expedition whose proceedings form the subject matter of these volumes, departed from and returned to that Province, such an account appears to me a fitting sequel to my narrative.

TRAVELS IN AUSTRALIA

CHAPTER I
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CHARACTER OF THE AUSTRALIAN CONTINENT--OF ITS RIVERS--PECULIARITY OF THE DARLING--SUDDEN FLOODS TO WHICH IT IS SUBJECT--CHARACTER OF THE MURRAY --ITS PERIODICAL RISE--BOUNTY OF PROVIDENCE--GEOLOGICAL POSITION OF THE TWO RIVERS--OBSERVATIONS--RESULTS--SIR THOMAS MITCHELL'S JOURNEY TO THE DARLING--ITS JUNCTION WITH THE MURRAY--ANECDOTE OF MR. SHANNON--CAPTAIN GREY'S EXPEDITION--CAPTAIN STURT'S JOURNEY--MR. EYRE'S SECOND EXPEDITION--VOYAGE OF THE BEAGLE--MR. OXLEY'S OPINIONS--STATE OF THE INTERIOR IN 1828--CHARACTER OF ITS PLAINS AND RIVERS--JUNCTION OF THE DARLING--FOSSIL BED OF THE MURRAY--FORMER STATE OF THE CONTINENT--THEORY OF THE INTERIOR.
The Australian continent is not distinguished, as are many other continents of equal and even of less extent, by any prominent geographical feature. Its mountains seldom exceed four thousand feet in elevation, nor do any of its rivers, whether falling internally or externally, not even the Murray, bear any proportion to the size of the continent itself. There is no reason, however, why rivers of greater magnitude, than any which have hitherto been discovered in it, should not emanate from mountains of such limited altitude, as the known mountains of that immense and sea-girt territory. But, it appears to me, it is not in the height and character of its hilly regions, that we are to look for the causes why so few living streams issue from them. The true cause, I apprehend, lies in its climate, in its seldom experiencing other than partial rains, and in its being subject to severe and long continued droughts. Its streams descend rapidly into a country of uniform equality of surface, and into a region of intense heat, and are subject, even at a great distance from their sources, to sudden and terrific floods, which subside, as the cause which gave rise to them ceases to operate; the consequence is, that their springs become gradually weaker and weaker, all back impulse is lost, and whilst the rivers still continue to support a feeble current in the hills, they cease to flow in their lower branches, assume the character of a chain of ponds, in a few short weeks their deepest pools are exhausted by the joint effects of evaporation and absorption, and the traveller may run down their beds for miles, without finding a drop of water with which to slake his thirst.
In illustration of the above, I would observe that during the progress of the recent expedition up the banks of the Darling, and at a distance of more than 300 miles from its sources, that river rose from a state of complete exhaustion, until in four days it overflowed its banks. It was converted in a single night, from an almost dry channel, into a foaming and impetuous stream, rolling along its irresistible and turbid waters, to add to those of the Murray.
There can be no doubt, but, that this sudden rise in the river, was caused by heavy rains on the mountains, in which its tributaries are to be found, for the Darling does not receive any accession to its waters below their respective junctions, of sufficient magnitude to account for such an occurrence. [Note 1. below]
[Note 1. The principal tributaries of the Darling, are the Kindur, the Keraula, the Namoy, and the Gwydir.