Chap. II] the Himalayan series. 27 



Himalayas, as in other mountain regions, that the ridges occur along 



synclinal axes in the strata. This character is 

 Ridges on synclinals. 



even more markedly exhibited in the Subathu 



group than among the Krol rocks. In the Krol and the Boj we find this 



structure exaggerated into a quaquaversal convergence of dips. It 



is best exemplified in the Boj. The main road passes round the sharp 



south-east end of this elongated hill, and on all three sides the rocks 



are seen to have a steady and high dip inwards. At the summit this 



arrangement produces the strangest appearance, though it is only what 



might be expected with such a peculiarity of dip. There is a narrow 



rim of limestone surrounding a deep hollow, which in form perfectly 



resembles a crater. The bottom of this hollow cannot be much less 



than one thousand feet from the rim, and there 

 Crater-like hills. 



is but one exit, by a narrow slit on the north- 

 west side, through which a small stream of water passes to the Blini. 

 There are three such craters, or cups, in a distance of four miles and 

 a half, which is about the length of the Boj ridge. It were impossible 

 to account for such a structure as this by any single operation of dis- 

 turbance, but it would readily result from flexures corresponding with 

 the actual run of the ridge, if the strata had been previously broken into 

 moderate anticlinal and synclinal folds in a transverse direction. The coin- 

 cidence of two synclinals crossing each other nearly at right angles might 

 evidently produce, by the aid of denudation, these crater-like hollows. 

 From the section before us it would seem easy to determine what the 



rocks are which underlie the Krol group. Along 

 Underlying black slates. 



the road, on the south side of the Krol, there are 



numerous clear cuttings, showing the Krol limestone and sandstone most 



regularly and conformably overlying black, carbonaceous, shaly slates. 



In following the section downwards into the valley towards Kanoge hill, 



the same description of rock appears throughout. On the Boj Ave find a 



precisely similar section : along the stream which flows from its inner 



