6GS Notes on the Geology of the Punjab Salt Range. [No. 7. 



No. 8. — Soft yellowish sandstone containing the lignites of 

 the range, 25 ft. 



No. 9. — Carbonaceous shale, (alum shales,) containing the 

 Kala Bagh coals, 25 



„ Nummulitic limestone, 60 



„ Carbonaceous (alum) shales, with nummulitic 



limestone bands, 80 



„ Nummulitic limestone, 



As these beds are merely indicated in the range, the manufacture 

 of alum is confined to the west of the Indus, for which Kala Bagh 

 has long been celebrated. The supply of shale or "rol" is quite 

 exhaustless, and is obtained by cutting shafts and galleries 

 into the outcrop of the beds. These workings sometimes ignite 

 spontaneously, and the combustion proceeds very actively, owing to 

 the large amount of jet and carbon in the shales. "When at Kala 

 Bagh I entered one of these miniature volcanoes, and accidentally 

 selected the upcast shaft as my way out ; my sufferings in which 

 should act as a warning in future to visitors to the mines : for I can 

 fancy few less pleasant ways of entering into or quitting the world, 

 as the case may be, than through this dread Avernus. 



No. 9. — Nummulitic or upper limestone. — This limestone is one 

 of the most important and extensively developed rocks in the range ; 

 occurring throughout its entire extent, and forming the greater 

 portion of the table-land and the summit of Mt. Sakesa. It is first 

 seen at the north-west base of Mt. Tilla, but is there not more than 

 100 feet thick ; thence it rapidly becomes thicker, but is not more 

 than 800 feet thick anywhere in the range. At Kotki, however, 

 the thickness is not under 1100 feet, including the shaly associated 

 beds previously mentioned. The prevailing colour of the rock is 

 white and whitish-grey, much of the compact kind being pink, and 

 some of the softer beds are yellow. A few argillaceous and dark 

 bituminous bands occur, but the general character of the rock is 

 pretty pure. Plints are common, generally as nodules, like the English 

 chalk flints, and in strings ; but towards the west end of the range 

 and across the Indus the flint also occurs in strata or plates.* 



* I should previously have mentioned that an impure flint or chert of a yellow- 

 ish colour occurs sparingly in the lower limestone. 



