112 KHASI HTLLS. 



Passing Northwards from Cherra Poonjee, the metamorphic rocks are 

 Blue and Gre Schi ts Concealed by the tertiary sandstone, until tliey are 

 *"^- again exposed on the Northern side of the deep 



glen close to and North of Mow-iDhlang, across which the road to Assam 

 passes. Here the general character of the rocks is very different. 

 They are blue and grey flaky schists associated with quartzose, and mica- 

 ceous layers, dipping at high angles, and with tolerable continuity to the 

 North and West. Some of the beds near to this are smooth-drained 

 gritty clay slates, of a greenish-blue colour, and flaky. In one or two 

 places attempts have been made to extract slates for roofing purposes 

 from these beds. In these rockS, however, there has been but 

 little " cleavage" structure superinduced, and the surfaces of the original 

 lamination of the rock, which are the only surfaces along which it can 

 be separated, are too uneven and at too irregular intervals to admit of 

 slates suitable for or^linary purposes being obtained from them. Heavy 

 coarse flasjs mi^ht be raised here, and these would ansv/er well for the 

 covering of out-offices, sheds, &c. 



In this glen, the slate rocks rest immediately upon or against a great 

 mass of greenstone (to which I shall refer again), 



Greenstone intrusion. . . ■ i i i ■ t 



and at the junction are considerably indurated, 

 and at the same time split up by numerous divisional planes which pass 

 across the laminae, and break up the mass into small angular pieces. 

 Similar greenstone is seen cutting through the rocks in several places to 

 the North of this, and on the surface is decomposed into a coarse ferru- 

 ginous, or ochrey mass. The slates continue of the same general character, 

 as far as the remarkable flat called Lung-king-ting-now. Descending 

 into this flat from the higher ground to the South, there is a considerable 

 thickness of black earthy slates, with hard gritty quartzose layers, 

 also black in colour. These slates are markedly different from any 

 of the rocks in the vicinity, and are not met with again in the section. 

 They are probably the uppermost beds of the entire slaty series met 

 with in this district. 



