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Charles Fenner : 



course of these streams was decided by and set out on the sloping 

 coastal plain. When their valleys were once selected, they would 

 soon carve through the lose, level-bedded tertiary sediments, and 

 then cut down into the soft, decomposed Jurassic mudstones. Under 

 such conditions very Avide, open U-shaped valleys are found. 



Underlying these last-mentioned sediments, and in some cases 

 immediately below the tertiaries, very hard gneisses and granites 

 were met, with the result that narrow, fairly steep-sided gorges 



Fig. 4.— Sketch of gorge cut by Robertson's Creek into the hard schists and 

 gneisses which underlie the thin capping of level-bedded marine 

 tertiaries. 



mark the places where such superimposition occurred. Good 

 examples of such gorges are those of the Wando and Robertson's 

 Creek (Fig. 4), that of Corea Creek is much more precipitous.; 

 they provide patches of rugged and interesting scenery, quite a 

 break in the monotony of the level uplands into which they are cut. 



In the lower Wando and Wando Vale Ponds the course of the 

 stream, with its numerous large waterholes, has within recent years 

 quite silted up; probably this is mainly due to the opening up of 

 the hillside lands by agriculture. In summer the streams cease to 

 flow, but good water for stock may always be procured by scooping 

 out a hole in the sands of the creek bed. 



(d) The Upper Glenelg and "Brim Spring Gap."— The upper- 

 most parts of the Glenelg show a tortuous course. The stream 

 rises in the heart of the Grampians, at the " Chimney Gap," just 

 over the ridge from one of the south-flowing tributaries of the 

 Wannon. It then flows north-east 12 miles, north-west 18 miles, 



