Pliysiogra'phy of Werrihee Area, 249. 



•derderg have their rise there, as also have many other 

 Lerderderg tributaries, such as Split Tree, Frenchman's, Wild 

 Dog, Sargonne (? Sardine), Clear Water, etc. The remaining 

 Northern boundary of the Werribee basin is the Gisborne ridge, 

 which is separated from the main Divide by the eastward trending 

 valley of the Gisborne Greek, a tributary of the Saltwater River. 



The nature of the Divide may perhaps best be followed by de- 

 scriptions from various viewpoints along its course in this area. 

 On the whole it stands up very little above the general level of the 

 lifted peneplain block which it traverses. The three highest points 

 visited by the writer are each due to the accumulation of volcanic 

 ■material. These points are : — 



(a) Leonard's Hill. 



(b) Old Bullarto. 



(c) Wuid Kruirk. 



(a) Leonard's Hill is a rounded volcanic cone clothed with fertile 

 soil, standing at an elevation of 2500 feet (aneroid). It is right on 

 the Divide, and close to the railway station of Leonard (Ballarat- 

 Creswick line ). To the north rise the head waters of the Jim Crow 

 Creek, a tributary of the Loddon, while on the southern side are 

 small tributary gullies which lead to the Werribee and the Eastern 

 Moorabool. Fine views are obtainable; to the east the Divide con- 

 tinues in densely timbered Ordovician ranges, Avell seamed by 

 gullies of very moderate relief. To the West, this feature has a 

 similar aspect, except that a high timbered ridge occurs, and partly 

 shuts out the view; far to the west, however, may be seen the dim 

 blue outlines of the parallel N.S. ranges of the highlands of West- 

 ern Victoria (ref. 22). 



The aspect of the Divide, where it lies in the Ordovician and 

 appears most likely to have been uninfluenced by the newer basalt 

 flows, is what one would expect to find where two sets of streams, 

 flowing in opposite directions, were competing for territory by 

 headward erosion. Possibly the predisposing causes of the two 

 opposite flowing sets of streams already existed on this block of 

 upland itself. On the other hand, the factor which gave the streams 

 their present directions might have l)een the let-down country to 

 the N, and S. ; creeks and rivers would then head back into the 

 highest block, almost independently of the surface-levels of that 

 block. The lifted block may even then, of course, carry on its 

 surface a set of stieam channels which existed on the ancient pene- 

 plain. 



