1842.] of the Himmalay a Mountains. cxxxiii 



rock is with difficulty accessible, but from the indications observable, 

 I should judge it to be micaceous schist. This rock indeed surrounds 

 the base of the high ridge which itself is composed of granite, occasion- 

 ally of a highly crystalline grain. It appears to contain two different 

 kinds of felspar, one of which assumes that arrangement which may 

 entitle the rock to the appellation of porphyritic. It is a very beautiful 

 rock. The mountain is conspicuous from every other quarter, and in every 

 view of it the summit patch of granite is at once distinguishable from 

 the micaceous schist below by its peculiar rocky aspect and bareness. 



283. I have now to give a few details on the occurrence of the 

 sandstone formation which bounds the mountain tract to the South 

 towards the plains. This rock assumes many different aspects here as 

 it does in Europe; upon the whole, the resemblance is sufficiently 

 striking to allow of our identifying it with the newer red or saliferous 

 sandstone, (the red sandstone of English geologists.) It is either a hard 

 red gravelly clay distinctly stratified, or the same clay enclosing rounded 

 stones, or a micaceous sandstone, which in hardness varies from loose 

 sand to a rock that will strike fire. This type is again modified by the 

 admission of rounded pieces passing into sandstone conglomerate. 

 These two rocks form the principal part of the formation. The sand- 

 stone is always micaceous in a high degree ; it is most commonly of the 

 ordinary colour, but sometimes it is found of a dark bluish grey, in which 

 case it seems to loose its appearance of a schistose structure, and becomes 

 amorphous, breaking equally in every direction. The type is farther re- 

 markable for containing kernels of superior hardness to the base, which 

 itself is more compact, and I might say clayey, than the ordinary sand- 

 stone. It also contains less mica. This grey type also passes into the 

 conglomerate structure ; besides these, which are the most marked types 

 that have any extent, there are innumerable varieties of very anomalous 

 appearance, chiefly towards the upper part of the rock. The yellowish 

 grey ordinary sandstone often alternates with a rock that might pass 

 for a perfect greywacke. The latter is seldom marked with the strata 

 lines like the sandstone, but is conformable and parallel to it. One 

 of the most remarkable features is the occurrence of ellipsoidal-shaped 

 cavities in the middle of sandstone strata. They are of different sizes. 

 One which I observed measured six feet in its longest diameter, and 

 was quite smooth and regularly curved in its interior. 



