DESCRIPTIVE GEOLOGY : SLATE ZONE. 99 



memoir. I was early attracted to it as being a most accessible and 

 typical part of Hazara. I must here state that in the descriptions 

 which follow, my indebtedness to Waagen and Wynne will be appa- 

 rent on every page to all who have read their joint paper. Here and 

 elsewhere I have endeavoured to follow their lead as regards their 

 classification and interpretation of the rock structure, and have only 

 departed from it when obliged to by very decisive facts. 



Sirban hill has already been said to be a bold massive hill feature 

 of the " writing-desk " kind, rising steeply from the alluvial country 

 round about. Its aspect from the north and from the south-east can 

 be gathered from the views (PI. 6 and 9). 



To describe the geology of Sirban in a few words is scarcely 

 possible, and I must ask the reader's patience whilst I take him from 

 one point to another in a somewhat erratic manner, for only by so 

 doing can I put the matter before him in a clear and consistent 

 way. 



We will begin by visiting the little shut-in glen with amphi- 

 theatre-like crags all round it in the neighbour- 

 hood of Tanakki. There we have exposed 

 the lowest formation, namely, the slate series. Only in this valley 

 and along the south-eastern margin of the Sirban hill-mass do the 

 slates emerge normally from beneath their great load of overlying 

 limestones (Infra-Trias to Nummulitic, inclusive). The Tanakki glen 

 may be looked upon as a rough anticlinal in the rocks above the 

 slates, open towards the south-west by the glen spreading away into 

 the alluvial flat of the Dore river, and arched over towards the north- 

 east, not by a regular unbroken anticlinal of Infra-Trias, etc., but by 

 an irregular arch broken by the tail end of the great north Sirban fault 

 (see on) on its northern side, and by a sharp reversed fold accom- 

 panied by a huge dislocation on its southern side. The slates keep 

 a low position in the valley and present no features different from 

 those described under the heading of Petrology, except that there 

 are no interbedded limestones. The varying amount of sandy mate- 

 rial mixed with the more argillaceous slates makes it an easy matter 

 H 2 4- 99 ) 



