338 
PROCEEDINGS OE SECTION C. 
water-level in the beds was reduced to the level of the sea, unless the 
bead of water were from time to time replenished. 
Some evidence has been adduced to prove that leakage of the first 
kind actually takes place. Professor David, in a lecture in November, 
1893, described “powerful springs of fresh water at Port Macdonell, 
rising up from the floor of the ocean at somelittle distance from the shore 
and discolouring the water for some little distance around*” Again, 
Mr. G. S. Griffith, in the Deports of the Australasian Association’s 
Christchurch meeting, says that “ along the south coast of Australia, 
between Warrnambool and the Murray mouth, the sea literally bubbles 
up with fresh water which has leaked up through the sea-sands.” Mr. 
E. F. Pittman says in the paper just read before this Section — “The 
artesian basin may extend to the southward, possibly even under the 
Eocene beds of the Lower Darling, the north-western portion of 
Victoria, and part of South Australia to the Coorong, where fresh 
water has, I believe, long been known to escape from the beach.” 
The observations of Professor David, Mr. Griffith, and Mr. Pittman all 
evidently refer to the same district. If Lower Tertiary rocks form the 
cliffs, the fact that the water leaks from them above the sea-level has 
no direct bearing on the question of an outlet for the Lower Cretaceous 
strata. The Tertiary cliffs may, for any evidence there is to the 
contrary, extend beneath the sea, and leak out there sufficiently to 
account for the phenomena referred to by the observers quoted. I 
cannot deny that the Lower Cretaceous formation may crop out at the 
sea bottom still further out to, sea, but the fact is not proven, and in 
the nature of things it is not likely to be proven. 
Nor is evidence of the second kind of leakage to hand. The out- 
crop of the Blythesdale Bravstone as it falls away from its highest 
altitude at Forrest Vale down to the Maeintyre Kiver is not very con- 
spicuously marked by springs. Indeed, given a continuous outcrop of 
a stratum such as this falling away from a higher level to a lower, it 
is easy to understand that water permeating the stratum would simply 
saturate it, and would never, except where locally covered by clay, rise in 
the form of a fountain, though it might All hollows in its surface, such 
as are made by river courses or covered by alluvial sauds and gravels. 
The mapping of the “ Blythesdale Braystone” is the work of the 
last eight months, and consequently no observations have yet been 
made to determine the proportion of the water brought down by any 
given river crossing their outcrop which is absorbed by the bibulous 
strata. A calculation on similar lines has, however, been made by 
Mr. II. C. Bussell, with regard to the Darling Kiver. Mr. Kussell 
writes*: — “ The mean rainfall on the Darling Kiver catchment for 
the past ten years has been 22*14 inches, and of this only 1| per cent., 
or 0*33 inches of rain, passes Bourke in the river. If 25 per cent, of 
it, which is equal to 5*53 inches of rain, passed away in this river, as 
it does in the Murray, there w ould be seventeen times as much water 
passing Bourke as now actually does pass .... and w*e ought, 
therefore, to have an underground water supply at least equal to sixteen 
times as much water as passes Bourke now. . . That we do not 
find it in the Darling is to my mind proof that it passes away to 
underground drainage.” 
* In “The Source of the Underground Water in the Western Districts,” Journ. 
.Royal Society N.S. Wales, 1889. 
