March, 1849. GEOLOGY OF PUNKABAREE. 407 



The quartz below this dips north-north-west 45° to 50°, 

 and alternates with a very hard slaty schist, dipping north-west 

 45°, and still lower is a blue-grey clay-slate, dipping north- 

 north-west 30°. These rest on beds of slate, folded like the 

 quartz mentioned above, but with cleavage-planes, forming 

 lines radiating from the axis of each flexure, and running 

 through all the concentric folds. Below this are the plum- 

 bago and clay slates of Punkabaree, which alternate witli 

 beds of mica-schist with garnets, and appear to repose 

 immediately upon the carboniferous strata and sandstone ; 

 but there is much disturbance at the junction. 



On re-ascending from Punkabaree, the rocks gradually 

 appear more and more dislocated, the clay-slate less so than 

 the quartz and mica-schist, and that again far less than the 

 gneiss, which is so shattered and bent, that it is impossible 

 to say what is in sit/', and what not. Vast blocks lie super- 

 ficially on the ridges; and the tops of all the outer mountains, 

 as of Khersiong spur, of Tonglo, Sinchul, and Dorjiling, 

 appear a pile of such masses. Injected veins of quartz are 

 rare in the lower beds of schist and clay-slate, whilst the 

 gneiss is often full of them ; and on the inner and loftier 

 ranges, these quartz veins are replaced by granite with 

 tourmaline. 



Lime is only known as a stalactitic deposit from various 

 streams, at elevations from 1000 to 7000 feet; one such 

 stream occurs above Punkabaree, which I have not seen ; 

 another within the Sinchul range, on the great Rungeet 

 river, above the exit of the Rummai ; a third wholly in the 

 great central Himalayan range, flowing into the Lachen 

 river. The total absence of any calcareous rock in Sikkim, 

 and the appearance of the deposit in isolated streams at 

 such distant localities, probably indicates a very remote 

 origin of the lime-charged waters. 



