18G7.] the Western Himalaya and Afghan Mountains. 49 



M 





m 



V8, 



1, granite ; 2, gneiss and mica- 

 schist ; 3, sandy shales and coarse 

 slate without fossils; 4, pale dolo- 

 mitic limestone containing patches of 

 Steatite ; 5, pale ochre-coloured lime- 

 stone, the probable parent rock of the 

 Sphasronites found at the foot of the 

 mountain. 



To the north of the great glacier 

 Baltoro is that portion of the Kora- 

 koram Range known as the Mustakh 

 and crossed by. the Mustakh Pass at 

 an elevation of 18,400 feet. The 

 whole S. Western face of this Mus- 

 takh is covered by enormous glaciers, 

 through which the rocky spurs of 

 the mountains rise like islands and 

 promontories. These rocks Captain 

 Grodwin-Austen found to be lime-, 

 stone dipping to the N. E., but ha 

 failed to find fossils in it, though he 

 noticed traces and fragments of orga- 

 nisms. It is so very probable that 

 these beds are a continuation of the 

 limestone of the Masha Brum, that I 

 have not hesitated to colour them in 

 the map as Silurian. Of course, this 

 requires confirmation. Unfortunately 

 the difficulties of reaching even the 

 foot of these gigantic mountains are 

 nearly insurmountable. 



80. I could not get any informa- 

 tion on the nature of the rocks form- 

 ing the remainder of the Korakoram 

 Chain. The few European travellers 

 who ever saw the chain, agree, I 

 believe, in representing it as being 

 mostly composed of granite. 



