COUNTRY BETWEEN THE KOTAH AND PATLI DUNS. 41 



A word or two may be said here about the horizontal sections 

 which accompany this work. They are drawn with the horizontal 

 and vertical scales equal, from the heights and distances given on the 

 4-inch maps reduced one-half. Taking the datum line at the level 

 of the sea, this gives sufficient room in the section to represent the 

 folds of the strata without the exaggeration which follows on an 

 increase of the vertical scale. By looking at the sections fore-short- 

 ened lengthwise, any desired exaggeration for the sake of distinct- 

 ness can be obtained. The three sections across the Kotah dun 

 show the several steps by which an almost completely horizontal dis- 

 position of the Siwalik conglomerate becomes raised into folds and 

 faulted. 



Country between the Kotah and PAtli duns. 



The Sub-Himalayan zone here, also, is divided from the older 

 rocks by a reversed fault, presenting no peculiarities that need be 

 noted in this place. Its position can be seen on the map. The 

 lowest member of the Siwalik series, namely, the Nahan sandstones 

 and shales, though keeping generally to a position next this boun- 

 dary and north of the Upper and Middle Siwalik stages, has become 

 somewhat more entangled with the latter. This is owing to the 

 greater lateral compression of the area, and the appearance of 

 fresh outliers of the conglomerates north of their proper zone. The 

 scale of formations is supplemented here by the in-coming of the 

 Middle Siwalik sand-rock beneath the Upper Siwalik conglomerates, 

 and next to the plains. The map, therefore, shows three bands 

 of Sub-Himalayan rocks, which are respectively, beginning from the 

 south, the Middle Siwalik sand-rock, the Upper Siwalik conglomerate 

 and the Lower Siwalik or Nahan sandstone. In addition, there is 

 another broken line of outliers of the conglomerate to the north of 

 the main mass. 



I will now detail a series of individual sections. 



This river is larger and more important than any of the smaller 



streams we have yet met with west of Kala- 

 Kosi R. • . ^ . , 



dhungi. Its channel lies along a wide, open 



( 99 ) 



