348 Beport on the Geological Structure of the Salt Range. [No. 4t. 



The metamorphosis has doubtless been effected by the action of 

 sulphuretted hydrogen and sulphureous acid. These gases, generated 

 in the decomposing alum shales by passing through the fissured lime- 

 stone and porous gypsum which covers its surface, become mutually 

 decomposed, sulphur being deposited. Dumas in 1846 proved that 

 when sulphuretted hydrogen at a temperature above 100° Faht. 

 and still better when near 190°, comes into contact with certain 

 porous bodies, a catalytic action is set up, by which water, sulphuric 

 acid and sulphur are produced. In this way sulphur is universally 

 formed in nature, and even in volcanic countries, " no well authen- 

 ticated case of its sublimation in an uncombined state,"* is known. 

 The thickness of the sulphur formation is very trifling, but may be 

 observed over a space of about two miles along the strike of the 

 limestone. 



The sulphur is in small quantity and of a bright yellow colour. 

 It was formerly worked by Maha Raja Goolab Singh of Cashmere, 

 who found it unprofitable and removed his establishment to Nak- 

 bund (a most appropriate name for a sulphur manufactory), near 

 Kooshalgurh on the right bank of the Indus between Attock and 

 Kalibagh, where it is said, sulphur exists in considerable quantity. 

 The unsettled state of the hill tribes in the Kohat district prevented 

 our visiting the Nakbund sulphur deposit. "We are however 

 informed by Misser G-yan Chund, the present Tehsildar of Pind 

 Dadun Khan and former tax-man of the Salt Range salt mines, that 

 during the Seikh rule, he, for three successive years, from the above 

 locality extracted 1000 Lahoree maunds of sulphur, for the manufac- 

 ture of gunpowder for the Seikh army. This he was able to supply 

 at the rate of Rs. 6 per maund. He described pits of thirty or forty 

 feet in depth as being dug into the sulphur formation which he 

 reckoned of considerable extent. The mines are about five miles 

 from the Indus near a village called Rici and about three miles 

 below Kooshalgurh. 



The mode adopted by the natives for extracting the sulphur from 



its matrix is very simple. A hole is dug in the ground on which a 



large gurrah or earthen vessel with a wide mouth is placed. This is 



then filled with the coarsely powdered rock. A second gurrah in 



* Daubeny on Volcanoes, 2nd edition, p. 615. 



