On the eastward side of the plateau there are again no large rivers, and the rainfall is even less than at Adelaide; but there is enough to grow fine crops of wheat. We see much the same arrangement of zones as at the back of Sydney, but the wheat-belt is narrower and the rainfall rather less. Very soon we drop down into the rainless plains of the Murray basin, where the only cultivation is in the irrigated district round Renmark. Here we 14 can see them drying the raisins and loading them on to the little steamer which will take them down to near the mouth of the river. 15 They will then be sent on by rail to Adelaide, since the river has no good outlet to the sea. Yorke Peninsula and the western side of Spencer Gulf have a few small towns on the coast; inland they have no rivers but only dry pastures, salt lakes, and marshes. Here is one of these lakes in the Peninsula. The character of this district will 16 change in the future, as much of it is adapted for the growing of wheat which has already been introduced. The only considerable population at present is on the coast strip from Adelaide to Port Augusta, and on the back of the plateau, never more than a hundred miles from the coast. As we follow the railway northwards from Adelaide we shall find 17 that agriculture decreases with the decreasing rainfall; in place of crops we see cattle and sheep. Here is a typical station only 18 a hundred miles north of Adelaide, where the sheep seem to be in full possession. The further north we go the thinner is the settlement; and north of Port Augusta we shall only find it at a few favoured spots near the railway. Beyond Lake Torrens the plateau edge to the east trends away and disappears, and we enter the Lake Eyre basin. At one time this may have been a vast inland sea, as the remains of extinct animals show that the climate must have been very different from the present. Now it is a great clay plain, broken by low plateaus and ridges of sandstone, and with much of its surface covered with stones or mulga scrub. The lakes are salt, while the long rivers, shown on the map as flowing into them, may be only a string of mudholes for years together. Much of this region is still unexplored, and nearly the whole of it is useless. The railway ends at Oodnadatta, to which a train runs at rare intervals; and off the railway the camel, which has been 19 introduced into Australia for this purpose, is the only means of transport. To the east of this line something may be made of the country by boring through the clay to reach the artesian water, as we have seen already in Queensland and New South Wales; so that settlement may spread slowly towards these States. To the west is the arid plateau which covers so much of the central part of the continent--the Sahara of Australia.