Synopsis, 
321 
9. The sculpturing of the mountains now began, 
rain and rivers, heat and cold, doing the work. In 
this way the ravines and gorges were carved out. 
Volcanoes were also in activity on the mountains. 
10. The eastern, or coastal area was subsequently 
depressed. This made it possible for the sea to fill 
the gorges referred to. Sydney Harbour, with its 
many branches and bays, is a system of mountain 
gorges, into which the sea has flowed. The Hawkes- 
bury “ River” is a submerged river valley. 
The reader will probably note that mention is 
made neither of a Glacial Period nor of Pre-Historic 
Man — two subjects that are, perhaps, the most attrac- 
tive in the geological record. With regard to a Glacial 
period, the author is of opinion that no satisfactory 
evidence has been put forward to show that Australia 
participated in a Glacial Period in Tertiary or Post- 
Tertiary times. 1 
No chapter of the geological record is read more 
eagerly than that in which we first find some traces 
of man and his works. The added interest of a human 
element gives every new fact a wider and a higher 
significance. But for such facts we look in vain 
throughout Australia. We cannot say what future 
research may bring to light, but our present knowledge 
is summed up in a sentence — Man has no Geological 
History in Australia. 
1 The subject is discussed by the author in a paper entitled “On the Evidence 
(so-culled* of (Under Action on Mount Kosciusko Plateau.” Pro©. IJuneun Koe. of 
N.H.W., 181)7, part 4, page 79G, plates xxxvii-xxxix, 
