264 T. S. Hart: 



tlie first rock. The fir.st rock is inissinii' from the shaft, but it 

 continues on the opposite side of the little creek, and is tra.ce- 

 able to the south end of the Buninyonu' Estate. 



There is no reason to regard Lake Wendouree as a crater ; 

 it is only a shallow depression on the ed<ie of the hiA-a stream. 

 But the source of the Ballarat ■' first rock " at least must be 

 placed on the Common close to Wendouree. There is no cone 

 of volcanic fragments ; explosive action appears to have been 

 of little magnitude at the emission of this lava. This is the 

 present limit of the waters received by the Yarrowee ; the north 

 slope of the Common drains to the Burrumbeet Creek. The 

 barrier of volcanic hills in the Ascot Gap quite prevents a 

 northern outlet, and the Burrumbeet Creek is forced to flow 

 west, and eventua-lly to the Hopkins, though ordinarily the 

 waters do not pass Lake Burrumbeet. 



The original drainage of the elevating peneplain v/as then pro- 

 bably a,s follows: — In the western pprt one principal east and 

 west crest divided a north and a south fall, but in the neighbour- 

 hood of Ballarat there was another important crest further 

 south. It is not demonstrated, however, that any part of this 

 formed a Main Di'^nde, from which the waters flowed north to 

 the Murray. In its western part it is uncertain, but in the 

 eaistern part the Parwan Estuary lay between the southern crest 

 and a crest near the present Divide. Much of the waters from 

 the north would formerly reach the I'arwan, but they have been 

 diverted by the volcanic barrier of Mts. Ingliston, Darriwill, 

 Gorong, and an unnamed centre near Ballan. This has caused 

 the formajtion of the present rugged Werribee Gorge in the old 

 rocks, contrasting strongly with the smooth mitlines of the 

 Parwan valley in its soft nniterials. Further north there may 

 have been an east and west ridge at Tarrengower. 



Various suggestion- have been made as to the possible origin 

 of the nivide or of these ])arallel crests. Selwyn suggests "that 

 ihc tirst outline of the existini;' main watershed wa> determined 

 liy some slight and almost accidental undidation, that may either 

 h;ivc pre-existed on the old sea bed, or been produced during one 

 of the earliest brond and cquabii' upheavals, tlunt resulted in a 

 dry land surface.'' Professor (iregory regards it as connected 

 with the intru.-ion of a series of uranitic masses forn»ing a Pri- 



