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miles west of Mount Gambier, on the right of the road to 
Millicent, where it is five feet, false-bedding is seen. I have 
failed to discover any striated stones or animal remains in it; 
though roots and partially-decayed vegetable matter are common ; 
the vegetation, which grew on this surface, was destroyed by the 
showers of volcanic ash, and the remains of Banksias, &c., are 
not infrequent in the lowest stratum of volcanic tuff. 
On removing the sand from the underlying limestone, its sur- 
face is seen to be as smooth as a coarse limestone can be ; and is 
in strong contrast with a weathered face of the same stone. The 
conclusion is irresistible that the whole has been ground down by 
some hard substance. Ice? 
The leading surface-feature, as viewed from the summit of the 
Mount, is seen to be the presence of a number of irregularly- 
placed low hills, running in no definite direction, no cliffs, no 
valleys. These are hills of denudation, and in most cases are 
constituted of Woods’ “ Upper Crag,” and the quarries in the 
lower ground are chiefly in his “ Coralline Crag.” Their forma- 
tion cannot be due to rain, because of the smoothness of the 
surface where protected from weathering influences; or to run- 
ning water, as the slope of the ground, which is only about one 
to two hundred feet in sixty miles, would not be sufficient to 
create a rapid flow, were such a body of water possible. 
The phenomena, which cannot be satisfactorily explained with- 
out the aid of Jce, are (1) the angular and rounded stones in the 
sand-bed ; (2) the pot-holes ; (3) the smoothed surface of the un- 
derlying limestone ; and (4) the rounded outline of the hills. 
With regard to the thickness of the ice-cover, there is little to 
guide one in forming an opinion ; the small quantity of detritus 
may indicate a thick sheet, and the small size of the pot-holes 
suggests rapidly-moving ice, whilst the depth of denudation points 
perhaps to a thick ice-sheet, or at any rate to long-continued 
action. All strata of a later date than Woods’ “ Upper Crag” 
have been removed, and in some places his ‘‘ Coralline Crag” has 
been denuded to a depth of twenty-five or thirty feet at least. 
