DESCRIPTIVE GEOLOGY: CRYSTALLINE AND METAMORPHIC ZONE. 239 



and has been left so on the map. No hard-and-fast 

 boundary can be drawn. 



(6) The fresh quartzo-felspathic material of which the rock is 



composed, and the coarseness of the grain, indicate a 

 granitic source for it ; whilst the slight metamorphism 

 which the Tanols have sustained was doubtless due to 

 the intrusion of the basic trap dykes among them. No 

 single instance of the intrusion of gneissose-granite 

 among them is known to me. They seem indeed pretty 

 certainly to be younger than the gneissose-granite, and 

 in all probability to have derived their material from it. 



(7) In Jaunsar the ' Bawar ' quartzites seem unmistakeably to 



be the equivalents of the Tanols. Possibly also the 

 Boileaugunge quartzites, and much of the younger series 

 of similar rocks described by me north of Dudatoli, are of 

 the same age. In position and habit these rocks are 

 very similar. It is likewise not impossible that the great 

 Gondwana formation of Peninsular India is represented 

 in part by the Tanols. 



Sections in the Gundgurh Range. 



The Gundgurh range has been briefly alluded to, p. 92. It is a 

 somewhat isolated hill-range rising steeply on its south-eastern side 

 from the Hureepoor plain and lowering gradually at its south-west 

 termination towards the lower reaches of the Hurroh R. On its 

 north-western side it lowers gradually to the level of the Indus 

 which flows along its base. It is generally a bare and rough range 

 of uninviting waterless slopes ; but to students of Hazara history 

 Sirikot fort is of interest as the place where Captain Abbott during 

 the second Sikh war, August 1848 to February 1849, when cut off 

 from all outside assistance, succeeded in defending himself from 

 the rebellious Sikhs by means of the wild guerilla bands of Maho- 

 medans which he collected. 



Geologically this range illustrates very well the change of the 



( 239 ) 



