PROBLEM OF THE GREAT AUSTRALIAN ARTESIAN BASIN. 181 



A study of the isopotentials proves in the clearest manner 

 the present direction of movement of the Artesian water 

 and also shows that along a considerable lengtli of "intake" 

 on the east, the accession of waters, apart from the two 

 centres, cannot be much, and again, that beyond a point a 

 little to the north of Warren, no further feeding of the 

 water-bearing series is taking place, so that neither from 

 south nor west are any appreciable supplies being con- 

 tributed. The map also indicates, as pointed out by Pitt- 

 man, the error into which Gregory has fallen, when he 

 states that the pressures upon the meteoric theory would 

 be insufficient to bring the water to the surface at the 

 several places that he specifies. 



The evolution of the form and slope of the potential sur- 

 face is so intimately bound up with the Tertiary history of 

 the Basin that this will be reserved for discussion in the 

 later sections. 



(5) Sub-surface Springs.— Though certain evidence has 

 already been presented in Section IV in favour of the above, 

 the subject will not be pursued further here in view of the 

 additional remarks to be made later. It will be sufficient 

 to say that there are grounds for presuming that springs 

 were or are active in feeding the reservoir from below, and 

 that the waters they supplied or are supplying, were or are 

 similar in chemical composition to, and their temperature 

 either the same or somewhat higher than, those of the 

 Basin. 



VII. The Absorption and Transmission of Water. 



(1) Absorption. — One of the principal arguments quoted 

 in support of the meteoric theory is that the run-off of the 

 Murray River is much greater than that of the Darling, 

 though this has been denied by Gregory. For reasons that 

 will appear later on, the author has to express a doubt 

 whether this problem, to which appeal is being made, is 



