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these mountainous table-lands run down rapidly until they reach 

 the chief Tertiary plain of Central Australia, and there spread 

 out in time;j of flood over hundreds of square miles, until reform- 

 ing and gradually converging, they form, some distance above 

 Bourke, that muddy, ugly stream, tlie Darling River, which flows 

 thenceforth in a generally south-westerly direction for the re- 

 mainder of its course through steep clay banks, some 40 feet 

 high and 70 to 90 yards apart, until it junctions with the Murray; 

 while along its course, for great distances, it is impossible to find 

 a stone as big as a walnut. During heavy floods, which occur at 

 very irregular intervals, it overflows its banks, and the water, 

 with much flne mud in suspension, spreads over extensive plains, 

 filling numerous creeks, lakes and billabongs, the only points not 

 inundated being the peculiar red loamy sand-dunes. Between 60 

 and 70 miles above Wilcannia several creeks leave the river, and, 

 flowing southerly, till an extensive system of lakes which flank 

 Mount Manara and the scrubby rises immediately to the south ; 

 ultimately the outflows gather into the Tallawalka, which turns 

 abruptly west and enters the river below Menindie. Some idea 

 of the extent of country thus inundated may be formed from 

 the fact that the water continues to fill the most southern of 

 these lakes three months after it has ceased to flow out of the 

 river. 



Immediately south of Menindie, a western system of overflow 

 commences and fills Menindie, Cawndilla and Tandou lakes ; 

 and immediately below IS^etley Head-station the Anabranch also 

 leaves the river on the western bank, and, after filling up an ex- 

 tensive lake system of its own, finally reaches the Murray 15 

 miles below Wentworth, where its opaque muddy stream mingles 

 with the dark clear waters of the Murray. 



As the floods subside these immense flooded areas dry-up and 

 crack in every direction with numerous deep interstices, which, 

 when another flood advances, serve as conduit pipes for the water 

 to flow-down into the underlying sand stratum. Some conception 

 may be formed of the extent to which this occurs when we find 

 that it has been observed that for a whole week the flood has 

 poured-down into one such crack without beijig able to advance 

 further. 



That these subterranean waters must total-up to something 

 stupendous is clearly apparent when we recollect the hundreds 

 of square miles over which storage goes on, flood after flood; and 

 that several such basins must exist at different levels within 

 the whole Darling basin, the varied quality of the springs oozing 

 from the river-banks, at low water, puts beyond dispute. That 

 some very big basins also exist between Bourke and the western 

 slopes of the watershed appears very convincingly from Mr. 

 Russell's paper, which I now quote : — 



