Page:A sketch of the physical structure of Australia.djvu/93

81 between lat. 17&deg; and 22&deg;, likewise to an unknown extent into the interior, and to the plains round the Gulf of Carpentaria, which seem equally to spread out towards the same centre, and combine these facts with the existence of an immense desert plain in that central interior as visited and described by Captain Sturt, we are almost irresistibly induced to look upon all these low and level tracts as but separate portions of one immense plain, occupying by far the larger portion of Australia, like a great sea of low and level land, with the hilly districts rising from it like islands.

The known facts as to the climate and meteorology of Australia would confirm this supposition to a very considerable extent. The climate of all the colonies and all the coasts of Australia is remarkable for its dryness,—for its long droughts, and consequently for the little permanent water that is to be found in the country either as lake, pond, or river. In New South Wales, several periods of one, two, or three years have already occurred since its colonization in which not a drop of rain has fallen. Great rains indeed fall occasionally, apparently in all parts, but they are irregular and partial, form sudden floods of great magnitude and soon rush off the land into the sea, without leaving any large store of water either on the surface or in the depths of the earth. The only large rivers that are at present known are those which flow off the western slope of the Great Eastern Chain in New South Wales, and of these