cet ate NEO i se as oil Nor (ieee ae os 
Explorations in the Amoor Region. 403 
relation to its absolute height and its topographical features, be 
any 
i ‘Valleys, ; a g : 
Which either do not admit of precipitation at all, or with tee 
roc 
difficulty ; added to which, the decomposition of hard 
Masses is material] y retarded by the dryness of the atmosphere, 
and the want of snow and rain. aie : 
A further exposition will show that, leaving aside the peculiar 
ra which characterises the organic nature of this region, the 
