126 AUSTRALASIA. 



The topography of the mainland is pecuhar. There are 

 hill ranges running not far from the sea on the east, west and 

 part of the south coast ; in the eastern part they rise up to 

 7,000 feet elevation and in the west to 3,000 feet; on a good 

 portion of the south coast cliffs rise up to 500 feet above the 

 sea. Between these coastal ranges is a tableland consisting 

 chiefly of sandstone and extending over about one and a half 

 million square miles. Numerous comparatively short rivers 

 flow from the coastal ranges into the sea, while some others 

 run first inland and then turn to the sea ; the latter are of 

 considerable length, as for instance the Murray Eiver which 

 is 1,300 miles long and drains an area of about half a million 

 square miles before it finds its way into Encounter Bay in 

 South Australia. 



The central tableland is heated in summer, and this causes an 

 indraught of moist sea air which brings a good supply of 

 rain to the part of the Continent lying between the coastal 

 ranges and the sea. The central tableland, however, gets 

 rain only at irregular intervals, and its temperature in 

 summer is described to be " like a furnace blast." Some- 

 times the clouds surmount the coastal ranges, and in these 

 cases cause floods of rain to be poured out upon the central 

 plateau. The meteorological records show an average rain- 

 fall at 



Everywhere the rainfall decreases rapidly on going inland. 



