Reviews — Prof. J. W. Gregorys Dead Heart of Australia. 373 



supply from artesian sources, and tlie danger consequent upon the 

 present wanton waste of such water at the surface. A chapter is 

 (levoted to the gigantic proposal to flood Lake Eyre from the 

 sea ; but a few carefully prepared statements given (on p. 347) 

 by Mr. A. S. Kenyon, Sir Charles Tod, and others, show the futility 

 of such an attempt, at least so far as human agency is concerned. 

 At p. 148 Dr. Gregory gives us an epitome of the changes that 

 must have taken place in this inland sea basin. 



The region of Lake Eyre in Secondary (Jurassic) times must have 

 been slowly sinking till it was flooded by the sea, which steadily 

 encroached from the Gulf of Carpenteria in the north to Stuart's 

 Creek and Lake Torrens in the south. 



The sea subsequently retreated, and the great basin of Central 

 Australia again became land. A great uplift then occurred in 

 Eastern Queensland. The sea, after withdrawing from Northern 

 Australia, began to encroach upon the south, covering much of what 

 are now the coast lands of South Australia and Victoria, and extended 

 in gulfs thence far inland, especially up the Murray, so that the 

 Darling, the Murrumbidgee, and the Hume entered the sea as 

 independent rivers. 



The earth-movements which followed impressed upon South 

 Australia its main existing geographical features. The great valley 

 of South Australia was formed. The lower part of this valley 

 foundered beneath the sea and formed Spencer's Gulf, the northern 

 became the long basin of Lake Torrens. 



The Lake Eyre country also began again to sink, till the lake- 

 margin was, as now, thirty-nine feet below sea-level. Previously 

 the rivers, which now flow towards Lake Eyre, flowed south- 

 eastward to the Darling or had an independent course to the sea, 

 which then ran up the Murray River. As the depression of Lake 

 Eyre continued, the Cooper and the Diamantina were diverted to its 

 basin, where they accumulated as a vast inland sea. Round such 

 a sheet of water there must have been a heavy dew, and probably also 

 the rainfall was considerable, for the adjacent steppes were well 

 grassed and fertile, and large trees — now represented by their 

 petrified trunks — grew on the plains. The water of this lake was 

 fresh .... and was probably at least three times the size of its 

 present bed, and on its shores lived many giant kangaroos, giant 

 wombats, as well as wallabies, bandicoots, and marsupial rats. 



Crocodiles swarmed in the lake and its estuaries, and preyed upon 

 the primitive Queensland mudfish (Cei-atodus) and on huge bony 

 fish, all of which have long since disappeared from the waters of the 

 Lake Eyre basin. This condition of affairs did not endure. The 

 rainfall dwindled, the water-level sank, and the lake decreased in 

 size; the discharge from the lake could no longer keep open its 

 channel, and Lake Eyre lost its outlet ; its waters were henceforth 

 removed by evaporation ; the mineral matters carried into the lake by 

 the rivers were concentrated until the waters became salt, and the fish 

 and crocodiles were all destroyed. As the lake shrank in area, less 

 and less rain fell upon its shores ; the vegetation withered ; the once 



