1842.] of the Himmalaya Mountains. xci 



of an arenaceous composition, which is succeeded by a magnesian clay- 

 slate accompanied by quartz rock. The former frequently contains 

 patches of a soft white clay, which evidently originates in a decomposing 

 talcose schist, as the latter occurs in contact with it. 



200. The quartz rock is most abundant as we approach Peepul Point, 

 and immediately above the place of encampment there occurs a set of 

 appearances which I think deserve description. It is so seldom in these 

 mountains, that we can trace the junction of two rocks, that no oppor- 

 tunity should be lost where it is accessible of recording the phenomena. 

 Fig — will render the following description more intelligible; it is anomor- 

 phous rock, apparently one of the numerous types of argillaceous quartz 

 rock. It is seamed in every direction, as this rock very often is, but 

 exhibits no trace of stratification. C. which adjoins it, is perfectly dis- 

 tinct, the line of junction being strongly marked. It is a white are- 

 naceous rock covered with brown spots, crumbly, and with little consist- 

 ence, but feeling gritty in the mouth. It is probably quartz, or a 

 mixture of quartz and felspar, and the iron- stained spots may arise 

 from decomposing pyrites. It passes below into a tolerably hard rock. 

 D. is a series of thin folise or leaves (they can hardly be called slates) 

 of argillaceous schist, of a plumbaginous aspect ; they are soft, and soil 

 paper. The series in its progress upwards gradually diminishes in 

 thickness till it disappears ; it is a quartzose argillaceous schist, stratified 

 distinctly, the strata lying parallel to the preceding, nearly vertical. 

 This latter, like A, are types of the ordinary rock, which seems to oscil- 

 late just here, between quartz rock and argillaceous schist. 



201. The character of the rock C. (I can hardly call it a vein,) affords 

 strong promise of the existence of graphite in this quarter. This mineral 

 belongs to formations of the earliest sera, as anthracite has been referred 

 to the suppositious transition class, and coal to the sera of secondary 

 rocks. It is remarkable too, that the deposit from which graphite of the 

 best quality is procurable, and which indeed furnished nearly the whole 

 civilized world with the variety used for pencils, that of Borrodale in 

 Cumberland is situated in a clay slate on the border of primary moun- 

 tains. There does, it is true, appear some doubts as to the real nature 

 of this formation, for some insist that it comprises rocks of the trappean 

 type ; however this may be, it is not the less certain that argillaceous 

 schist is known often to contain very valuable beds or veins of graphite. 



