152 New South Wales. paet i. 



often sends promontories into the valley, and even 

 leaves in them great, almost insulated, masses. So 

 continuous are the bounding lines of cliff, that to 

 descend into some of these valleys, it is necessary to go 

 round twenty miles ; and into others, the surveyors 

 have only lately penetrated, and the colonists have not 

 yet been able to drive in their cattle. But the most 

 remarkable point of structure in these valleys, is, that 

 although several miles wide in their upper parts, they 

 generally contract towards their mouths to such a degree 

 as to become impassable. The Surveyor-General, Sir 

 T. Mitchell. 1 in vain endeavoured, first on foot and then 

 by crawling between the great fallen fragments of sand- 

 stone, to ascend through the gorge by which the river 

 Grose joins the Kepean ; yet the valley of the Grose in 

 its upper part, as I saw, forms a magnificent basin some 

 miles in width, and is on all sides surrounded by cliffs, 

 the summits of which are believed to be nowhere less 

 than 3,000 feet above the level of the sea. "When cattle 

 are driven into the valley of the Wolgan by a path 

 (which I descended) partly cut by the colonists, they 

 cannot escape ; for this valley is in every other part 

 surrounded by perpendicular cliffs, and eight miles 

 lower down, it contracts, from an average width of half 

 a mile, to a mere chasm impassable to man or beast. 

 Sir T. Mitchell 2 states, that the great valley of the Cox 

 river with all its branches contracts, where it unites 

 with the Nepean, into a gorge 2,200 yards wide, and 

 about 1,000 feet in depth. Other similar cases might 

 have been added. 



The first impression, from seeing the correspondence 



1 ' Travels in Australia,' vol. i. p. 154. — I must express my obliga- 

 tion to Sir T. Mitchell, for several interesting personal communica- 

 tions on the subject of these great valleys uf New South Wales. 



* ' idem,' vol. ii. p. 358 



