PROBLEMS OF THE ARTESIAN WATER SUPPLY OF AUSTRALIA. 121 



a high percentage of mineral salts in solution as if it had 

 been in contact witli slates, shales, or limestones. A com- 

 parison of the analyses of the artesian waters with those 

 of mine waters fully bears out this conclusion, as the follow- 

 ing figures will show. All the available analyses of waters 

 from the porous beds of the artesian basin in Queensland, 

 New South Wales, and South Australia have been taken for 

 the purpose of this comparison. 



WATERS FROM POROUS BEDS OF ARTESIAN BASIN. 



143 samples from Queensland give an average salinity of 



47*94 grains per gallon. 

 177 samples from New South Wales give an average salinity 



of 56*35 grains per gallon. 

 14 samples from South Australia give an average salinity 



of 141*62 grains per gallon. 

 The average salinity of the 334 samples from all three 

 States is 56*32 grains per gallon. 



All the available analyses of Australian Mine Waters 

 have also been collated. There are 35 of these, viz. 2 from 

 Victoria, 11 from New South Wales, and 22 from West 

 Australia, and their average salinity is 1674*48 grains per 

 gallon. These waters were all taken from comparatively 

 shallow depths, and their high salinity, as compared with 

 that of the artesian waters, is evidence of their having 

 been in contact with more highly mineralised rocks. If 

 now we consider the conditions under which plutonic waters 

 would occur, having their source at great depths, and 

 percolating, under extremely high temperature and pres- 

 sure, through calcareous, ferruginous, and felspathic rocks, 

 it is obvious that their salinity would be far in excess, not 

 only of the artesian waters, but of the mine waters referred 

 to above; it might, in fact, be expected to amount to many 

 thousands of grains per gallon, for the waters, under such 

 peculiar conditions of heat and pressure, would become 

 supersaturated with salts. 



