202 



VII. of its Proceedings, that at Overland Corner the Newer 

 Tertiary is a tluviatile deposit resting iin conformably against the 

 escarpment of the older formation. 



In support of this is the fact that at the cliffs, on the eastern 

 bank of the River Darling, a few miles below the Anabranch 

 Cutting, there is exposed at low water coarse red sandstones, 

 which, accepting Sir A. C, Ramsay's opinion, as quoted by the 

 Professor, must have been deposited in inland isolated waters ; 

 and I think close examination of the sandstone at Tanberry 

 Point, still further up the river, will prove it to be the same for- 

 mation. 



The irregularly-stratified sands and clays between these two 

 extremes — Tanberry Point and Overland Corner, some 150 

 miles south-westerly — afford further fluviatile evidence, as also 

 do the brightly-coloured clay-cliffs exposed at Lake Victoria Head- 

 station. 



For our purposes, however, we will take a line westerly from 

 Tanberry Point towards the boundary of this province. South of 

 this line many of the deeper wells are salt. Though shallow, 

 fresh-water basins exist, as, for instance, at Coombo Lake, the 

 most westerly lake filled from the Anabranch overflows, a very 

 ample supply of water was struck at 20 feet ; the water con- 

 tains a good deal of magnesia, and the clays forming the bed of 

 the lake contain a large proportion of crystallised gypsum. 



I should here like to hazard the opinion that at one time — a 

 far distant period, no doubt — the Lachlan River emptied itself 

 into the Newer Tertiary basin under present consideration, and 

 that the present Willandra Creek is its representative. 



This Newer Tertiary basin, thus roughly defined, measures at 

 its widest 140 miles across. Within its area, water is always 

 to be obtained in a bed of very fine white sand, always at about 

 the same relative depth, and, allowing for local peculiarities, of 

 the same quality, namely, slightly saline ; beneath this stratum 

 are other water-bearing ones, as is proved by the bores in Silistria 

 and Aldborough Wells. As to the source of these waters there 

 can be no doubt; and to make it perfectly clear it is necessary 

 to give a short description of the topographical features which 

 render the Darling River so interesting a study to geologists, 

 though the region is indeed quite as interesting to botanic 

 students from the same cause, viz., the extraordinary alternations 

 of flood and drought. 



The watershed of the Darling extends from lat. 33|° to 25^-° 

 south, and embraces the whole western flow of water be- 

 tween these parallels from the high table-lands, which skirt 

 Eastern Australia at a distance roughly estimated as averaging 

 200 miles from the Pacific coast. The large rivers formed in 



