112 
Geology and Physical Geography : 
finds a temporary resting-place on the low lands, the general effect 
is loss of such matter by its being carried away to form fresh 
deposits in the ocean bed. 
The general conclusions which suggest themselves as to the 
Australian Cordillera are that, in Lower and Middle Palaeozoic 
times, a continuous land surface, approximating in general direc- 
tion to the present mountain system of Australia, extended from 
New Guinea to Tasmania; that the portion of the Victorian Main 
Divide, from St. Clair to the Grampians, was a great lateral spur 
from the Main Chain; that during the Upper Palaeozoic or Lower 
Mesozoic periods a strait was eroded to the south of where the 
La Trobe and Lang Lang Valleys now lie, thus breaking the con- 
tinuity of the land surface between Australia and Tasmania; that 
subsequently to the deposit of the Victorian Mesozoic rocks in, 
and the filling up thereby of, that strait, a fresh one was eroded 
further south, between Corner Inlet aud Tasmania; that the pre- 
sent irregular and sinuous course of the main water-shed line is due 
to the successive denuding agencies which have been at work since 
the continent first appeared as a land surface, and that these 
forces have from time to lime been modified or altered in their 
direction by the sedimentary rocks deposited in later times, during 
periods of submergence, or by the products of volcanic action at 
various epochs. 
It would bo tedious to attempt to describe all tho cases where it 
is evident that portions of the crest of the Cordillera were once in 
different positions to the present line. Enough instances have 
been already noticed in this work to indicate some of the 
alterations that have taken place — the incalculable abrasion and 
degradation to which the ancient rock foundation and subsequent 
formations bavo been subjected, and the immeasurable lapse of 
time that must have been occupied in bringing about the present 
configuration of the country. 
Difficult as it may he for the human mind to realize, the truth 
of the main principles enunciated by the late Sir Charles Lyell, 
and in which he has been followed by other eminent geologists, is 
strikingly evidenced in the geological phenomena observable in 
Victoria, which indicate — that to such slow action as wc see now 
in progress in this and other parts of tho world, varied by periods 
of greater or less intensity, changes of climatic conditions, gradual 
alternate submergences and risings of the land surface, and other 
natural causes, with occasional abnormal or cataclysmic move- 
ments, all our varied rock-formations and the alterations in tho 
physical structure of the country from the remotest geological 
epochs to the present day may be confidently ascribed. 
