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AUSTRALIA AND ITS GOLD REGIONS.
T will perhaps help us to form an idea of the climate and situation of Australia, if we imagine it brought up into our own part of the world, and twisted round, so that the parts nearest the equator in the southern hemisphere shall be those nearest it in the northern.* Let us imagine,
then, the meridian of Greenwich to represent the 140th meridian of east longitude, and let us proceed to arrange Australia in the northern hemisphere with reference to that meridian, putting each place in its corresponding latitude. In this case, Melbourne would
be near Gibraltar; Sydney and Moreton Bay would be places on the coast of Morocco; and Cape York would be in the interior of Africa, about the latitude of Sierra Leone Port Essington would be situated between the Niger and Lake Tchad, the coast-line running thence through the heart of Africa to the borders of Nubia; Swan River would be on the Mediterranean coast of Egypt; King George's Sound about Candia; and the Great Australian Bight would correspond with the shore of Africa stretching from the Levant to Algeria, Adelaide lying in the country between Algiers and Mount Atlas. If, indeed, the great Desert of Sahara, with all the neighbouring parts of Africa and a portion of Spain, were to remain above water, while all Europe and the greater part of the rest of Africa were sunk beneath the sea, we should have, in the great island thus formed, a tolerable representation of Australia, so far as climate at least is concerned, if not perhaps in some other respects.
Our object in introducing this bit of hypothetical geography, is to impress on the reader's mind the necessity of dismissing from his imagination all comparisons between Europe and Australia, and especially all preconceptions derived from our own green islands here at home. Let him rather call up to his memory, and furnish his imagination with ideas derived from the burning suns and the glowing air of Africa; let him think of the parched sands of the desert, the arid rocks, the boundless plains, the almost inaccessible mountain-ranges, that we read of as existing in many parts of that country. Nor let him altogether dismiss from his recollection, that under the Roman Empire the northern shores of
*The reader is here presented with a paper which we are not disposed to see ranked below any work on the same subject, of whatever external pretensions, as it is the composition of a gentleman of distinguished scientific attainments, who writes from intimate personal knowledge of Australia.-ED.
Africa were the granary of the world; though it would be well if he prepared himself not to hear of any majestic rivers like the Niger and the Nile rolling with unabated flow from the distant mountains to the sea.
Having offered this correction of local prejudices and associations, let us now proceed to Australia, not where it might have been, but where it is, and endeavour to give to the reader some idea of its physical structure and characteristics.
Every one knows that Australia is a great squarish-shaped continental island, about 2000 miles across from north to south, and 2500 from east to west, with the tropic of Capricorn running through the middle of it, so that its northern coasts reach within 11 degrees of the equator.
Along its eastern side there runs a band of mountainous country, from Cape York on the north, to Wilson's Promontory on the south. This mountainous tract stretches even across Torres Strait, in the shape of a line of rocky steep islets, up to the shores of New Guinea, and across Bass's Strait, by a similar chain of islands, into Van Diemen's Land. Van Diemen's Land itself is entirely composed of lofty and broken mountains, with their accompanying valleys and hollows, having several points 5000 feet above the sea, and many mountainous masses 3000 or 4000 feet high.
In Australia, the mountains of the eastern chain rise 6500 feet in a part called the Australian Alps, or Snowy Mountains, in about south latitude 36°, and this is the loftiest point at present known in the country. There are numerous mountains rising 4000 feet all along its course, as far north as Cape Melville, near south latitude 14°, beyond which the chain gradually declines in height and importance. This great eastern chain must not be looked on as a single range of mountains, but as it is here described, a band of mountainous country, 50 or 100 miles in width, and altogether about 2500 miles long.
In the Port Phillip District, or the province of Victoria, as it is now called, are several short ranges of mountains, fifty miles long or so, running north and south, and rising 3000 or 4000 feet above the sea. In South Australia, also, is a north and south mountainchain running from Cape Jervis, about 400 miles long, the peaks of which rise sometimes between 2000 and 3000 feet high. This chain terminates on the north in a very curious horseshoe-shaped depression, about thirty miles in width, and scarcely above the level of the sea, called Lake Torrens.
Between the high lands of the eastern chain and those of Victoria and South Australia, lies the basin of the Darling and the Murray, the two principal rivers of south-eastern Australia, which empty their united waters into the shallow Lake Alexandrina, whence they ooze rather than flow into the sea.
All the interior of the country, from the Darling and Lake Torrens to the Gulf of Carpentaria, and thence to the borders of Western Australia and the north-west coast, is probably for the
most part one vast plain, unbroken by any important range of mountains. The rivers that flow into the interior from the flank of the eastern chain are gradually absorbed by the sands of this plain, and no large rivers come out anywhere on the coast, either of the great Australian Bight, along the north-west coast from Sharks Bay to the Buccaneer Archipelago, or round the Gulf of Carpentaria.
We now must say a word or two on the geological structure of these mountains and plains. The great eastern chain is very largely composed of granite, which forms some of its most lofty and massive mountain groups, and often appears in the beds of its ravines beneath the other rocks. On the granite rest great but irregular masses of gneiss, mica-slate, chlorite-slate, clay-slate, and other metamorphic rocks. These are frequently traversed by granitic dikes and veins, as also by large intrusive masses of granite, syenite, porphyry, greenstone, and other similar igneous rocks. Upon this metamorphic set of rocks rest here and there large and regularly stratified sheets of unaltered rocks, principally sandstone, with interstratified beds of shale, and some beds of limestone. These rocks are full of fossils, resembling those found in the Devonian and Silurian rocks of Western Europe. Beds of coal of wide extent, but of no great aggregate thickness, are associated with these rocks. The total thickness of these paleozoic rocks, as they are called, probably does not exceed 3000 or 4000 feet--the coal-beds being probably confined to about 400 feet of them. The paleozoic rocks are found principally on the flanks of the chain, stretching in basin-shaped expansions between its lateral spurs. The country around Sydney is one of these slightly basinshaped districts. Igneous rocks of several kinds traverse these paleozoic rocks likewise, but never, so far as is known, in sufficient quantity to produce any great alteration in them; neither are any of the fossiliferous rocks at present known to be affected by slaty cleavage.
From the Glenelg River to the mountain-range of South Australia stretch great tertiary plains, traversed by the lower part of the Murray River. It is probable that these tertiary rocks spread into the great desert plains of the interior. The mountainchain of South Australia contains no granite; it is composed partly of clay-slate, traversed by great quartz veins, partly of mica-slate, gneiss, and other similar rocks.
Having thus briefly described the skeleton of the country, let us endeavour to give the reader an idea of its general aspect, the character of its vegetation, and its climate.
If we sailed across Bass's Strait to Port Phillip, after passing the bare granitic ridge of Wilson's Promontory, we should see before us a shallow bay. Entering this, and passing through a narrow opening in a low woody shore, we should find ourselves in an inland sea, about thirty miles in width; on reaching the centre of which, we should just perceive the tops of the trees on the horizon all around us. On the right, we might discern in the
distance the high land forming the mountains of the eastern chain; while before us, and on our left, we should see single groups of hills rising at intervals, with a graceful sweep from the low land around them. On our right, a few miles up the creek of the Yarra-Yarra, is the straggling, half-finished town of Melbourne; on our left, the smaller, but snugger and pleasanter, town of Geelong. Both stand on gently undulating ground, but little raised above the sea, a plain stretching from one to the other, and thence far into the interior to the north and west. Excellent wheat-land abounds here, and the country has a pleasanter and more cheerful aspect than many other portions of Australia. Still, the monotonous gum-tree forest spreads its unfailing wilderness of trees far and wide over the land, broken here and there perhaps by groves of banksia (called the honey-suckle), or of casuarina (called the she-oak), the mimosa (or tea-tree), and other spiny, thorny, or bristly-looking denizens of the Australian bush.'
Over the undulating plains, whether covered by forest or not, we could gallop our horses, without the least hinderance, in almost any direction; and if they were old bush-horses, they would take care to steer clear of all stumps and stakes, to leap the fallen logs at the right places, and to carry us safely and pleasantly through mile after mile of the bush without much trouble on our part. Nor would there be likely to be anything of interest to detain us on the way. The greenness and freshness of forests in other parts of the world, the luxuriant underwood, the dark shady recesses, and cool grassy glades associated in our minds with the word forest, have but little counterpart in the Australian bush. Imagine an illimitable expanse of untidily-kept gravel-walk, bare, dry, and dusty, with a few long, straggling blades of living hay, not grass, occurring at intervals, and the leafless stems of ragged-looking trees rising in regular open order all around you, and you have a picture of the ordinary bush of Australia. The multitude of trees is sufficient to check all ordinary currents of wind, and produce a lifeless stillness in the air, which the aromatic smell of the gum-trees renders heavy and oppressive; meanwhile, the leaves and branches overhead are too few and far between to intercept all the rays of the sun, which still fall hot upon your head, so that the heat of the bush is often more overpowering than that of the most open and shelterless country. Still, we may canter on and up the swelling sides of Station Peak, Mount Macedon, or Mount Alexander itself, without meeting any serious impediment. If, however, we were to attempt to penetrate the recesses of the eastern chain, we should probably be soon stopped by deep, inaccessible gullies, and impenetrable masses of 'scrub.'
If, now, we transfer ourselves to the neighbourhood of Sydney, and prepare to penetrate into the interior, we should see before us a portion of this eastern chain, usually called the Blue Mountains, composed of a low, very gently sloping bank, of a level and uniform height at top, about 2800 feet above the sea. A peak