175 



absence of surface streams. Swamps abound, and in the 

 winter time these overflow and unite as broad flowing sheets 

 of water. 



The rocks are in the main very porous, with abundant 

 caverns, collapses, and "run-away holes." The limestones 

 contain the extensive sub-artesian fresh-water basin of the 

 miocene "Murray Gulf," the waters of which are mainly 

 derived from local rainfall and from the rainfall in the 

 adjoining counties of Lowan and Follett (Victoria) . ( 9 ) The 

 average rainfall at Mount Gambier itself is 30 to 35 in. 

 Near the coast the water-table of the sub-artesian basin is 

 cut by the land surface, and beautiful streams of fresh water 



Bl ue U Kfc Leg of (VJuHon lake 



Punch-bow 



^3 



Tower 

 ("Point" 



Fig. 1. 

 Sketch of the present-day remnants of Mount Gambier, 

 looking E.S.E. along the line of the lakes, to show the 



chief features. 



emerge at such places at Ewen Ponds, Dingley Dell, and the 

 interesting miniature mound springs near Beachport. The 

 surface of the underground water is about 70 to 80 ft. above 

 sea level at Mount Gambier (140 ft. above sea level), and 

 is there exposed to view in a series of four beautiful lakes. 



The limestones decompose to a red clay, and the chief 

 modifying feature of the surface soils is the peaty 



(9) Maps submitted to First and Second Interstate Confer- 

 ence on Artesian Water (A. S. Kenyon), 1912 (p. 32 of report) 

 and 1914. 



