ARTESIAN WATER IN N. S. WALES AND QUEENSLAND. 439 
It was true that at Kissingen carbon dioxide probably played an 
important part in the forcing of the water to the surface. It was 
generated, not of course, as Mr. Dixon had already shown, by any 
possible action of the gypsum beds on limestone, but probably by 
the same cause which originally converted the limestone into 
gypsum, which might be still in operation at a depth, the cause 
possibly being the action of weak sulphuric acid on limestone, 
In New South Wales carbon dioxide was rarely met with in 
artesian water. The group of mud or mound springs on the 
Lower Flinders River in Queensland, referred to in his previous 
paper were an exception, as bubbles of carbon-dioxide were con- 
stantly rising through the water at these springs, but it was never- 
theless not present in sufficient quantities to justify the supposition 
that this gas exercised any material expulsive force on the water. 
It was probably generated by the action of sulphuric acid resulting 
from decomposing pyrites in the lignitic beds or brown coals of 
the Lower Cretaceous rocks on the associated marly clays. He 
did not consider the oil wells of America a fair parallel to cite for 
comparison with the artesian wells of New South Wales. It was 
the fact that gas pressure contributed largely to force the oil to 
the surface at the American oil wells, but the gas pressure was 
assisted by hydrostatic pressure, as it was commonly the experi- 
ence that when the gas and oil in the well became exhausted, 
brackish water took their place, and this rose to some height in 
the bores. ‘The actual amount of pressure measured at any of the 
bores in New South Wales or Queensland, did not much exceed 
200 ibs. per square inch, a pressure which could easily be explained 
by the difference in level between the hydraulic grade and the 
level at the point where the pressure was experienced. 
The theory as to the artesian water having its origin in great 
subterranean lakes, which had become crusted over with siliceous 
sinter had already been shown to be untenable by Professor 
Liversidge and Mr. Russell. He would like however toadd that 
it was a geological anachronism to assume that artesian water 
could be derived, as suggested by Captain Gipps, from the lakes 
