chat. tii. Great Valleys, 153 



of the horizontal strata, on each side of these valleys 

 and great amphitheatre-like depressions, is that they 

 have been in chief part hollowed out, like other 

 valleys, by aqueous erosion ; but when one reflects on 

 the enormous amount of stone, which on this view 

 must have been removed, in most of the above cases 

 through mere gorges or chasms, one is led to ask 

 whether these spaces may not have subsided. But con- 

 sidering the form of the irregularly branching valleys, 

 and of the narrow promontories, projecting into them 

 from the platforms, we are compelled to abandon this 

 notion. To attribute these hollows to alluvial action, 

 would be preposterous ; nor does the drainage from 

 the summit-level always fall, as I remarked near 

 the Weatherboard, into the head of these valleys, but 

 into one side of their bay-like recesses. Some of the 

 inhabitants remarked to me, that they never viewed 

 one of these bay-like recesses, with the headlands re- 

 ceding on both hands, without being struck with their 

 resemblance to a bold sea-coast. This is certainly the 

 case ; moreover, the numerous fine harbours, with their 

 widely branching arms, on the present coast of New 

 South Wales, which are generally connected with the 

 sea by a narrow mouth, from one mile to a quarter of a 

 mile in width, passing through the sandstone coast-cliffs, 

 present a likeness, though on a miniature scale, to the 

 great valleys of the interior. But then immediately 

 occurs the startling difficulty, why has the sea worn out 

 these great, though circumscribed, depressions on a 

 wide platform, and left mere gorges, through which 

 the whole vast amount of triturated matter must have 

 been carried away? The only light I can throw on 

 this enigma, is by showing that banks appear, to be 

 forming in some seas of the most irregular forms, and 

 that the sides of such banks are so steep (as before 



