Notes on Geology and Mineralogy of Affghanistan. 587 



along its base, but extend far in among the granites and 

 primary limestones which constitute the mass of the forma- 

 tion. The granite too, varies exceedingly in texture and 

 composition, and seems to pass by gradation from a volcanic 

 product to true granite : this is particularly apparent at 

 Kishk-i-nakhood, on the road to Greeshk, for the mountains 

 there exhibit three kinds of granite, which have very much 

 the appearance of being stratified ; the fact is however, that 

 the mass constitutes truly but one bed, the lower part of 

 which is in contact with basalt, and has quite the appearance 

 of a volcanic rock ; this feature fades away higher up, and 

 the granite assumes a different colour and texture, while the 

 surface portion again changes to a true granite. This triple 

 bed is not abruptly terminated at the points of change, nor 

 is there any division of it to authorize the inference of stra- 

 tification, but the basal structure passes gradually into the 

 central, and that again into the true granite. There is also 

 a curious dyke of granite possessing the structure of the 

 lower part of the mass, which not only traverses the whole 

 granitic bed, but runs up to the very summit of the range 

 through thick strata of variously coloured limestones tra- 

 versed in all directions by veins of crystallised carbonate of 

 lime, where it terminates, without overlying them. It would 

 seem from this circumstance as if the heat of the volcanic 

 rocks beneath had fused the lower portion of the granite, 

 and caused it to burst upwards through the superincumbent 

 strata, retaining the colour and texture of the heated mass 

 from which it had been suddenly ejected. Shortly after 

 our arrival at Candahar, I was despatched with an escort of 

 fifty i\fFghan horsemen, to seize some grain which was re- 

 ported to have been concealed in a village in the valley of 

 Kakraez, and although my errand proved M a wild goose 

 chase," it gave me an opportunity of seeing something of 

 the rocks which form the mountains on the western side of 

 the Argandab. Our route lay west of Candahar, and after 



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