INTRODUCTORY. 11 



they are possibly the extension of the strata containing rock-salt found 

 on the same general line to the west in the Punjab, 



Next comes the most valuable of Dr. Flemiug-^s reports, that accom- 

 Dr. Fleming's second V^^^^^ by a map and sections.-^ In conducting his 

 report, 1853. survey. Dr. Fleming had the advantage of the 



assistance of Mr. William Purdon, the memory of whose engineering 

 improvements still lasts in the Salt Range, and also that of Mr. William 

 Theobald, now one of the senior officers of the Geological Survey of 

 India. Considering the short space of time allowed for the completion 

 of the examination, the report may be fairl}' called exhaustive. Errors 

 as to the positions assigned to certain groups in his former report are cor- 

 rected, the physical features and botany described, and full details of the 

 geological structure and development of additional groups in the 

 western part of the range are given. 



The mode of mining the salt, manufacture of alum, washing of 

 gold, and sublimation of sulphur, are described at length, and the position 

 and character of the coal deposits and petroleum springs are noticed. 

 Analyses of some of the rocks are inserted ; and the organic remains, 

 together with the minerals, receive attention in the description of each 

 of the principal groups in which the rocks are classified. 



In a passage upon the upheaval of the range. Dr. Fleming makes 

 deductions as to the various depths at which the strata were deposited and 

 other physical conditions, arguing from the conformity of the whole 

 that they had all been elevated subsequently to the deposition of the 

 newer tertiary beds. The upheaving force he thought extended from the 

 east to the west, perhaps progressively, but this is not plainly stated ; and 

 though he looked upon Mount Tilla as shewing an anticlinal structure, 

 he favours the idea of the elevation having taken place along a line of 

 fracture further westwards and having affected a greater area. Beyond 



* Report on the geological structure and mineral wealth of the Salt Range in the 

 Punjab, with maps, sections, &c., by the same author, in charge of the Geological Survey 

 of the Salt Range in the Punjab, season 1851-52 : Jour. As, Soc, Bengal, 1853, p. 230, &c. 



(' H ) 



