Notes on Geology and Mineralogy of Affghanistan. 575 



series of rocks and formations belonging to the European 

 secondary and tertiary systems, from the mountain limestone (?) 

 through the coal measures, oolite, chalk, tertiary strata, and 

 diluvium. 



From the conformable position of the conglomerate and 

 sandstones, it is evident that they must have been deposited 

 previous to the uprise of the secondary strata which sup- 

 port them ; but there are other vast accumulations of boul- 

 ders, and loose or unconsolidated conglomerates which oc- 

 cupy the beds of the Pass at Sir-i-Bolan and other parts 

 lower down, the occurrence of which is due to other and 

 more recent causes. These have all the appearance of having 

 been heaped together by waters, and in many places they 

 appear unconformably to overlie the upturned edges of the 

 secondary strata, that is, in a horizontal position. It may 

 be inferred therefore, that after the deposition of the ter- 

 tiary beds the uprise of the secondary rocks from beneath 

 the ocean in which they had been formed, caused vast waves 

 to rush down from the rising hills, through the glens and 

 valleys to which the movement gave rise, and that the dis- 

 placed waters carrying with them the boulders of the shat- 

 tered rocks, together with vast quantities of the loose 

 shingly beds of diluvium, gave origin to the accumulations 

 of horizontal conglomerates now met with in the bed of the 

 defile ; and these being subsequently exposed to the action 

 of the elements and the streams which drain through the 

 Pass from the surrounding heights, became furrowed out 

 and channelled precisely as they appear at the present day. 



It may probably be farther inferred, that the elevation 

 of these mountains was contemporaneous with that of the 

 Himalayas and Siwalik ranges, for nearly the same series of 

 rocks is observable in both, and the tertiary and diluvial 

 beds of the latter rest conformably against the secondary 

 strata as they do in Affghanistan, while the probable identity 



