VREDENBURG ! SKETCH OF BALUCHrSTAN DESERT. 



wonderful colours, combined with the exquisite shapes of the cliffs, 

 give to the scenery a degree of beauty which it would otherwise 

 lack on account of the almost complete absence of vegetation. 



The degree of alteration which has produced these colours is of a 

 moderate degree; but in other places the mineral vapours have altered 

 the rocks far more completely. The volcano was a solfatara in one of 

 its last stages, which is probably also the stage now reached by the 

 K6h-i-Tafd3n. It is in the eastern portion, principally all round the 

 "Miri, " that the effects have been most pro- 



Solfataric action. 



nounced, but other patches of similarly affected 



rocks have been observed further west, the most important ones being 

 shown on the map, and a portion of the volcano Damodim, west of 

 K6h-i-Sult£n, also exhibits the same phenomena. The scenery all 

 round the Miri Hill is of the most extraordinary character, slopes 

 thousands of feet in height being entirely coloured in the most 

 brilliant tints of red and yellow. All the rocks, whether agglom- 

 erates or lavas, have been transformed into soft clays of bright 

 colours. Where the transformation has not proceeded so far, the 

 shapes of the minerals can still be discerned, but generally every 

 original character has been obliterated, save occasionally the 

 stratification. Owing to their friability, these altered rocks have not 

 weathered into the same vertical cliffs as elsewhere, but they are 

 cut up into innumerable ravines with countless branching furrows 

 and ramifications, in the manner which characterizes the denudation 

 of a homogeneous argillaceous rock. 



These clays are all impregnated with sulphate of alumina, which is 

 extracted and used as a mordant, under the name of " Koh Mak. " 

 In this country, where it does not rain for years at a time, it 

 gradually effloresces in the shape of white tufts, which are collected 

 under the name of " Phul Mak." I did not see the latter 

 substance, as an exceptional shower of rain had destroyed it just 

 before my visit. Some pale yellow clays contain soluble salts of 

 iron in addition to those of alumina. The iron salts combine with 

 certain vegetable substances and with the sulphate of alumina to form 

 ( 100 ) 



