4S WYNNE : TRANS- INDUS SALT REGION., KOHa't DISTRICT. 



ture models of hill ranges, with serrated knife-edge ridges and deeply- 

 gullied sides, or where it is (as is not uncommon) traversed by rectan- 

 gular veins of greater hardness, the interspaces between which are 

 often eroded into perfectly flat-bottomed hollows like little salt-pans ; the 

 surrounding lips of these sometimes have no opening or depression to 

 enable the water to drain off, so that the dissolved mineral from within 

 can only have been removed by the wind or by overflow. 



This system of rain furrows, always more or less upon the same 

 plan, may be frequently found upon surfaces of homogeneous limestone, 

 more frequently upon gypsum, and most largely developed upon the 

 exposed exterior of the rock-salt. 



Another result of the solubility of the gypsum is its apparently 

 frequent recomposition or rearrangement into a rock somewhat re- 

 sembling calcareous tufa. This form of the mineral or rock occupies, 

 as a covering, much of the gypseous ground, conforming rudely to its 

 surface even in deeply cut ravines. Such masses, on being searched, 

 may be found to contain some decayed fragments of limestone in 

 which are nummulites as well as pieces of other local rocks, and in 

 the paste small crystals of dolomite and bipyramidal clear quartz may 

 be met with. Unlike calcareous tufa, stems, leaves of plants, &c, do not 

 appear to have been preserved by incrustation or replacement. 



The gypsum not limited to one zone. — Though prevalent in great and 

 more or less continuous masses, the gypsum cannot be said to form an 

 unbroken sheet, its apparent discontinuity being perhaps due to disloca- 

 tion or denudation, or both. Nor is it limited either above or below by 

 any arbitrary boundary. Thus, in the Malgeen Saya (Malgin Seya) 

 hills a layer of salt was seen to separate a mass of dark gypsum from 

 the rest above ; in other parts of the eastern side of the district layers 

 of limestone, or of limestone and clay, were observed near the top 

 of the main gypsum mass; beneath a less strongly developed bed of the 

 latter, and in about the centre of the salt region, thick bands of gypsum 



( 152 ) 



