Correspondence. 571 



At Layagard the mountains presented to Dr. Lord a very extraordi- 

 nary appearance, which he thus describes — " The hitherto uniform tints 

 of the mountain were soon to be variegated with red, green, and ashen 

 grey, which on examination we found to be produced by ochre, red in- 

 durated clay, decaying green-stone, and strata of volcanic ashes. These 

 indications of ancient volcanic action, carried along with them efflores- 

 cence and sheets of sulphate of lime, the deposits of springs which had 

 whitened large tracts on the side of the range extending westward 

 as we continued our course to Chandi, the volcanic indications being 

 generally at an inconsiderable elevation, and in most instances capped 

 by conglomerate, or beds of clay, to a depth of 50 to 200 feet ; the valley 

 we were told stretched away west and south-west, until it nearly reach- 

 ed to Bameean, but the upper end of it was inhabited by the Kaikh Ali, a 

 lawless tribe of Hizarahs, who acknowledge no ruler, and rob every one 

 that comes within their grasp, so that for a long series of years this 

 road has been closed to the traveller and the merchant ; we were there- 

 fore obliged to terminate our researches at Chandi, but it gave me no 

 little pleasure, on a subsequent journey, to recognise the very same vol- 

 canic indication with basalt and amygdaloid superadded in the vale of 

 Tohak, which is distant about 40 miles SW. from the point where we were 

 now to turn back, and to trace these indications through Topchi up to 

 Bameean itself, and finally to identify by its mineralogical characters, 

 as well as by its geological connexions, the conglomerate from which 

 the caves of Bameean are scooped, and its gigantic idols carved, with 

 the conglomerate of the vale of Ghorbund. 



Here we think Dr. Lord has fallen into an extraordinary error in 

 considering the " ashes," as he calls them, to be volcanic. From the 

 account he has given, we are led to suppose that these so-called ashes 

 are nothing but decomposed claystones, claystone porphyries, and 

 claystone tuffas. We have frequently examined the Pentland hills in 

 Mid Lothian, Scotland, in company with individuals who were well 

 acquainted with the volcanic district of Auvergne, &c. and who remarked 

 the similarity between the decomposed claystones, porphyries, and 

 tuffas of the former, with the volcanic tuffas and ashes of the latter. 

 In the Pentland hills you have the claystone tuffa, which in many 

 places is much decomposed, passing into claystone porphyry, and it 

 into felspar porphyry or compact felspar, and these again are associ- 

 ated with amygdaloid, &c. and all bursting through or displacing 

 the Neptunian strata, which consists of greywache, greywache slate, 

 clay slate, old red sandstone, conglomerate, and sandstone. But before 

 we can be correct in our premises, we must see a collection of rocks from 



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