202 WALTER HOWCHIN 
Earth movements that have subsequently transpired have, in 
places, obscured the evidences of glaciation. A regional uplift, 
followed by extensive block faulting, occurred during the later 
Cainozoic times, when the Willunga and Mount Lofty ranges 
were elevated, and Gulf St. Vincent was developed by a series of 
trough faults. The effect of these movements has been to remove, 
through waste, the greater part of the morainic material from the 
elevated plateau, but at the same time the Senkungsfeld of Gulf 
St. Vincent has tended toward their preservation. A government 
bore put down, recently, at sea level, near Kingscote, Kangaroo 
Island, proved the glacial beds from the surface down to a depth 
of 1,094 feet, where they rest on Cambrian slates. 
While it is clear that the ice, in some of its stages, was sufficiently 
thick to pursue a course quite independent of the local contours, 
the valleys have retained the greatest evidences of ice erosion. It 
is probable that the main glacier, within the area now under descrip- 
tion, flowed down an upland valley that was in later times sub- 
merged through the land receiving a tilt to the south, and is repre- 
sented by Gulf St. Vincent at the present time. The bore at 
Kingscote, just referred to, probably penetrated this main valley, 
choked with its morainic material. 
The more interesting features of the glacial field are associated 
with what must be regarded as a glacier tributary to that which 
filled the depression of the Gulf. This tributary glacier occupied 
a wide valley, now drained by the Hindmarsh and Inman rivers 
and the Back Valley creek, together with their intermediate ridges, 
having an average width of 5 miles. The valley, at present, is 
truncated by the sea at its southern end, and follows a north- 
westerly course, up stream, passing over the present watershed 
of the Bald Hills and unites with the sea again at Normanville, 
on Gulf St. Vincent, having a land course of about 20 miles. 
The great interest attaching to the valley of the Inman, is in 
the glacial topography which it exhibits in very remarkable fea- 
tures throughout. The deepest floor of the valley, so far as at 
present known, was proved by a bore in Back Creek valley which 
penetrated 964 feet before touching bed rock and was in glacial 
till, sandstones, and bowlders throughout. This depth, added to 
