340 Report on the Geological Structure of the Salt Range. [No. 4. 



In all the commercial European alums as far as we can ascertain 

 the alkaline base is potash or ammonia, the former alkali being 

 characteristic of British alums while the latter occurs in those of 

 Trance. In the alum of Kalibagh, however, soda forms the alkaline 

 base, a fact which the addition of " Jumsan" to the crude alum 

 liquor first led us to suspect, and which an analysis of the alum sub- 

 sequently confirmed. A soda alum has hitherto, we believe, been 

 known only as an interesting chemical preparation, but previous to 

 1848, we are not aware that it had been noticed as a staple article 

 of commerce in the N. W. Provinces of British India. 



Considering the coarse apparatus in which it is prepared, its 

 purity is astonishing. It effloresces considerably on exposure to 

 the air, and has a slight pink colour arising from the presence of a 

 little iron which strikes a blue colour with yellow prussiate of 

 potassa, and only contains a trace of muriate of soda. Although 

 alum is only manufactured Trans-Indus, alum-works might, we 

 believe, be established with advantage in the Bukh ravine between 

 Mosakhail and Nummul, as there the alum shales are of considerable 

 thickness, aud wood and water could be obtained in abundance. In 

 other parts of the Salt Eange the alum shales are too inaccessible 

 and their thickness too small to be profitably worked as a source of 

 alum. 



Lignite or Salt Range Coal. 



Throughout the Salt Eange from Jelalpoor to the Indus and in 

 the Chichalee Eange, irregular seams of lignite, having, in many 

 places, the aspect of good bituminous coal, may be observed imbedded 

 in the lower alum shales. Lignite also occurs in the upper shales 

 but in too thin films to be of any use as a fuel. 



We shall notice the different localities where we have observed 

 the lignite deposit proceeding from east to west. 



Baghanwalla. This coal locality was first brought to the notice 

 of Sir Henry Lawrence by Lt. Eobinson, Bengal Engineers, who for- 

 warded samples of it to Lahore in the Autumn of 1847. Erom these 

 we made an analysis, the results of which, along with a few remarks 

 on the general characters of the coal, were laid before the Asiatic 

 Society of Bengal in February 1848. 



