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424 | T. W. E. DAVID. 
of the water of 5,200 feet. This locality would appear to be the. 
deepest as yet proved in the Cretaceous basin. 
None of the artesian bores in New South Wales have so far 
attained a depth of 3,000 feet, the deepest bore at present being 
2,573 feet, viz., that situated at Moongulla on the Collarendabri 
to Angledool road, and there is no direct, nor indirect evidence 
so far to show that the base of the Cretaceous anywhere in New 
South Wales is much over 2,000 feet below sea-level. The general 
dip therefore of the bed-rock in New South Wales is in a northerly 
direction towards Malvern Hills, as far as proved at present. 
The surface of the Rolling Downs Formation has however a 
general inclination to the south-west from the Dividing Range at 
the head of the Flinders River towards the Lake Eyre Basin. 
The altitude of the Dividing Range is a little over 1,000 feet, 
whereas few portions of the Lake Eyre Basin exceed 200 feet 
above the sea, the surface of Lake Hyre itself being thirty-nine 
feet below sea-level. But although the present fall is slight in a 
south-westerly direction, in early Tertiary Time it was probably 
greater for since the close of the Cretaceous Period, and chiefly 
subsequent to the deposition of the Eocene (?) limestones of the 
Nullarbor Plains, the southern portion of South Australia, Victoria 
and part of West Australia have been elevated from 600 to 800 
feet, while possibly the northern portion of the Cretaceous basin 
near the Gulf of Carpentaria has partaken in the downward move- 
ment of the northern portion of Queensland in the neighbourhood 
of the Barrier Reef, but of this latter movement, as far as known 
to the author, there is no good evidence. The effect of this tilting 
up of the earth’s crust from the south-west extremity near the 
Australian Bight towards the north-east would have the effect of 
reducing the amount of surface slope from the head of the Flinder’s 
to the Great Australian Bight. It is more than probable then, 
that a submarine outlet exists for part of the artesian basin vid 
Lake Eyre. 
The fact should here be mentioned that there is undoubted 
evidence of a movement in an opposite direction to that referred 
