STRATIGRAPHICAL ELEMENTS: CRYSTALLINES, ETC. 47 



Kush proper, possess a marked uniformity of composition and 

 structure, consisting as they do of a great complex of gneissose 

 and schistose rocks interwoven the one with the other, and laid out 

 in parallel flexure waves one behind the other. 



The geological and physical problems which arise from a study 



of the above are of great interest and import- 



Of great interest as ance w hen we consider that both as a first im- 



being a continuation or 



the Himalayan crystal- pression, and as a matured belief based on years 

 of study of them in the field, it appears evident 

 that this great complex is a continuation of the similar crystalline and 

 more or less metamorphosed rocks of Kashmir, also of those of other 

 parts of the Himalaya which have been partly described geologically 

 and some of which are personally known to me, ziz. } the Dalhousie, 

 Chamba, and Simla neighbourhoods, and parts of Tiri and British 

 Garhwal and Kumaun. For, as regards the nature, origin, and age of 

 these rocks, whatever can be proved true cf them here, must in all 

 reasonable probability apply equally along the length of the great 

 crystalline backbone of the Himalaya and Hindu-Kush. 



With the above far-reaching implications in view, and knowing 

 well what opposite opinions had from time to 



an?wering? S "^^ time been ex P ress ed by geological observers en- 

 gaged at different parts of these areas, I entered 

 on the examination of these rocks with the following questions or 

 possibilities constantly before me (neglecting for the present other 

 minor questions and side issues) : — 



(i) Is there evidence in this great crystalline backbone for any- 

 thing of the nature of an archaean series ? 



(2) Do any of the gneissose rocks represent foliated or rolled out 



granites or allied rocks that have come into their present 

 axial position in the great ranges by an intrusive process ? 



(3) In the latter eventuality what was the date of that intrusion ? 



(4) Are the crystalline schists, which are found associated with 



the gneissose rocks, truly metamorphosed sedimentary de- 

 posits, and if so, what was their original age when laid 

 down as sediment ? 



( 47 ) 



