34 SUB-HIMALAYAN ROCKS OF N. W. INDIA. [CHAP. 11. 



such beds as I have just described. These upper rocks are what 



Upper rocks most ' ai- would be called "metamorphic" ; they are highly 

 tere * foliated schists ; in parts, as on Jako, mica schists 



predominate ; elsewhere, as on Boileaugunge, they are siliceous. They are 

 sometimes even hornblendic and garnetiferous, as on the top of Jako, 

 and on the point just west of Boileaugunge. Besides being in a more 

 highly mineralized condition, all these beds show much more local crush- 

 ing and contortion than do the underlying slates, and, as a consequence, 

 they are very frequently traversed by large seams and veins of quartz, 

 which greatly add to the general metamorphic aspect. Quartz veins are 

 rare in the slates unless very locally along lines of strain. 



If then these strata be in their normal relative positions, and if the 

 identification of the limestone, &c, below the ridge, with the true Blini 

 limestone be correct, we must seek in the Simla beds for the representa- 



RepresentativesofKrol tiveS ° f r0cks that 0Verlie the BHni S r0U P in the 

 rocks at Simla. -^.^ sec ^ 0IL This can be done without any great 



strain on the facts. The schists of Jako must, in this case, be the representa- 

 tives of the shaly slates of Solun, — the black shales at the base of the 

 Krol. At a few spots, as along the Tibet road near the bazaar, on the 

 north side of Jako, we find some direct confirmation of this supposition 

 in the decided traces of a carbonaceous element in the schistose rocks. 

 In the same view the schistose quartzites of Boileaugunge, which in strike 

 would come over the Jako beds, and which extend down to the toll-bar, 

 at the gap to Tara Devi, would represent the Krol sandstones, only consi- 

 derably increased in thickness. At this gap there is a synclinal axis with 

 much of the black crush-rock about it ; it runs north 40° west, through 

 Jatog hill. On Tara Devi we have the reverse of the synclinal, and the 

 repetition of the Simla section, the highly garnetiferous schists, and the 

 schistose quartzites, all having a moderate dip to the north-north-east. 

 The high cliffs on the west face of this hill are of these latter rocks. Even 

 within so short a distance the thickness of the quartzites is less than on 



