3 
discarded l)ottles, which in certain districts, are pretty well the 
sole relics of departed greatness. 
Fig. 5. 
I ake Dundas, Norseman. Dundas Goldfield. 
It is mv ])urpose therefore to deal briefly with some of the 
problems which the rocks of the old plateau i)resent, the solu- 
tion of which olTers a peculiarly interesting subject for enquiry, 
ft is not however, intended to deal with the more recent and fas- 
cinating branch of geology v\'hich concerns itself with the origin, 
structure, and formation of the surface features of the State. 
'i'he rocks of which the i)lateau is made up present a hewikiei 
ing variety of lithological types, which bid fair to make this | 
tion of Western Australia a classic field for petrological research. 
Portions of the plateau have been examined during very many 
hasty traverses, which individually yield somewhat limited infor- 
mation, although collectively give a good general idea of the geo- 
logical structure. I'he rocks of the iilaleau have lieen most closely 
investigated in those districts in which the probability of economic 
development has necessitated detailed geological surveys. These 
localities are very widely separated, and it is now becoming im- 
peratively necessary to link up these districts by a study of the 
intervening areas, though many jiorlions being masked by residual 
and other deposits, the geological structure of these areas will, it 
is to be feared, in the absence of systematic l)oring. carried out 
under scientific guidance or extensive underground mining o])era- 
tions. remain more or less the subject of s])ecu]alion and inference. 
1'he oldest known rocks of Western Australia comprise a great 
group which almost everywhere constitute the foundation of the 
State: to the whole of these rocks however, observers have invari- 
ably assigned an Archaean age, but this is rather inferred than 
proved. 
I propose to retain the term Archaean for that great basement 
com])lex of schists, gneisses and allied rocks, but although this is 
