Physiography of Werribee Area. 265 



vician ridge about 50 feet high and a mile or so wide. Imme- 

 diately to the west, the divide between the eastern and western 

 branches of the Moorabool is much higher, in similar rocks, and 

 three miles wide. It might be expected that, accidents excepted, 

 the divide between any two well-established streams should be 

 more marked than between any two tributaries of one of those 

 streams, when the same rock type prevails. The facts thus suggest 

 that in pre-newer volcanic times the upper Werribee, and the upper 

 Eastern Moorabool were tributaries of the same system, the separa- 

 tion having been effected by Egan's Hill and the lava flows there- 

 from. 



The country rises considerably through the village of Korweingu- 

 boora, towards the Main Divide at Leonard's Hill. At Korweingu- 

 boora there are two south-sloping, much decomposed tongues of 

 basalt. A shallow valley on one of these tongues leads to the 

 Werribee, Avhile a similar tributary gully of the Eastern Moorabool 

 runs along the western side of the same flow. The country thence 

 rises to Leonard's Hill. This point is on the Divide, and has 

 already been described. 



Thence eastward, the Main Divide of Victoria separates the Wer- 

 ribee on the south from the Loddon and Campaspe Rivers on the 

 north, as detailed in a previous section. On the whole, the Divide 

 here is migrating northward. No captures from the northern 

 rivers are to be noted, and the advance northward by the head 

 waters of the Werribee and the Lerderderg is more in the nature 

 of a general " nibbling " along the whole front, rather than a 

 sudden acquirement of large territories by captures. 



From the Main Divide, south-east about seven miles to Mount 

 Bullengarook, the divide separating the Werribee basin from that 

 of the Gisborne Creek (a tributary of the Saltwater), is in thickly- 

 timbered Ordovician country. Enquiries from saw-millers who 

 had been through that part elicited the fact that a rough bush track 

 runs along this divide from Bullengarook to East Trentham. 

 This was not examined, but the steep ravines that were seen to 

 mark the headwaters of the Goodman's Creek and the Lerderderg, 

 when compared with the wide valley of Gisborne Creek, point again 

 to the more vigorous work being done in the basin of the Wer- 

 ribee. 



From Mt. Bullengarook the divide is irregular, running gene- 

 rally eastward through Mt. Gisborne. It is partly a high, well- 

 dissected Ordovician block, largely covered by basaltic hills and 

 flows. The gully heads of the Pyrete or Coimadai Creek, the 



