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AUSTRALIA [geography seem entirely absent in the interior. Neither are there any snow- extending from the Musgrave Ranges west and north. This may fields to feed rivers, as in the other continents. More remarkable be considered a plateau without any of the features of the plains. still, over large tracts of country the water seems disposed to flow The bed-rock is nowhere far from the surface, thus forming a away from, rather than to, the river-beds. As the low-lying plains strong contrast with the great alluvial plain where the bed-rock is are altogether an alluvial deposit, the coarser sediments accumulate buried many hundred feet below the surface. Over the entire in the regions where the river first overflows its banks to spread western half of Australia there is no leading drainage system, out over the plains. The country nearest the river receiving the and we have here an area that is almost unique in the features of heaviest deposit becomes in this way the highest ground, and so a continent. There is no high mountain, and probably over an continues until a “break-away” occurs, when a new river-bed is expanse of 400,000 miles not a drop of the scanty rainfall ever formed, and the same process of deposition and accumulation is reaches the sea. repeated. As the general level of the country is raised by sucThe term desert applied to the Australian interior is somewhat cessive alluvial deposits, the more ancient river-beds become misleading. Sandhills there are, and vast stretches of sandy buried, but being still connected with the newer rivers at some country. But much of the so-called desert will support animal point or other, they continue to absorb water. This underground life to some extent. Sturt’s “ Stony Desert ” is not at all what network of old river-beds underlying the great alluvial plains the name would suggest. Peculiar water-worn and glazed boulders must be filled to repletion before flood waters will flow over the cover much of the surface, but there is also grass, and in good surface. seasons the “gibber land” disappears under a waving carpet of Outside the great alluvial plain there is a vast tract of country meadow. Part of Sturt’s “Stony Desert” is now a sheep-run,
with one sheep to 10 to 12 acres, but growing excellent wool sooner or later they are lost in sand-hills, where their waters Genuine desert exists in the spinifex country. On the outskirt, disappear and a line of stunted gum-trees {Eucalyptus rostrata) is are shady bauhmia trees and bright-looking desert-apple trees all that is present to indicate that there may be even a soakage in the treacherous spinifex, too, looks fair enough from the distance an often puts on a coat of enticing verdure when the plains am these supposed rivers. Another notable feature of the interior is the so-called lake area, downs are parched and withered. It will grow almost on tin stretching to the north of Spencer Gulf. These lakes surface of a hard rock, and m most parts of the desert the bed aaredistrict expanses of brackish waters that spread or contract as the rock is covered with but a shallow coating of soil. The result i like a thousand knitting-needles thrown into a confused kind o season is one of drought or rain. In seasons of drought they are hardly more than swamps and mud flats, which for a time may tangle, with all the points sticking upwards, and this tangle grow; become a grassy plain, or desolate coast encrusted with salt. The larger and more formidable every year, until a bush fire happih country around is the dreariest imaginable, the surface is a dead sweeps it away and a new growth starts. Much of this part o level, there is no heavy timber and practically no settlement. the continent is now known as the Australian Steppes. The Lowei Lake Torrens is sometimes 100 miles in length. To the north Steppes extend over an area corresponding mostly to the extent o agafin stretches Lake Eyre, and to the west of Torrens Lake, Lake the Cretaceous formation. Their prevailing aspect is characterizec Gairdner. Some of these depressions are at, or slightly below, seaby flat and terraced hills, capped by desert sandstone, with stonecovered flats stretching over long distances. The country rounc level, so much so that a very slight depression of the land would of the interior with the Southern Ocean. Lake Lyre, where some of the land is actually below sea-level connect much the entire coast there extends a succession of mountain comes under this heading. The Higher Steppes, as far as the r Along es rom are known, consist of Ordovician and Cambrian rocks with an ,^fl£ f Cape Howe to Capefrom York. constitute a Corstretching 1700 miles northThese to south. average elevation of 1500 to 3000 feet above sea-level. Over thb |j dillera Mountain Several points rise to heights of from 4000 to 5000 feet, ran country water-courses are shown on maps. These run in wet mostly isolated peaks. Towards the south-eastern £es’ seasons, but in every instance for a short distance only and corner ofas the continent the peaks come closer, clustering around
