76 RANIGANJ COAL FIELD. [CHAP. IY. § 3. 



It is difficult to form an accurate estimate of the quantity of iron- 

 stone contained in these beds ; it varies through- 

 Quantity of ironstone. _ _ „ „ 

 out. In one place, near Jamsul, in 150 feet ot 



beds, 26 runs were met with, varying in thickness from 2 inches to 

 about a foot, and occurring at intervals of from 6 inches to 10 feet from 

 each other. The whole thickness, taking the average of each seam at 

 4 inches, was 8 feet 8 inches or about T X Y of the whole. This is probably 

 about the average of the upper part of the beds. It is exclusive of 

 many nodules from 6 inches to 3 feet in thickness, which are not regu- 

 larly interstratified, although, like similar nodules in the English iron- 

 stone formations, they may be found to recur on about the same hori- 

 zon for considerable distances. None of the seams appear to be conti- 

 nuous over large spaces, all thin out. There is, therefore, a proba- 

 bility that an attempt to follow up any particular seam or seams by min- 

 ing would not be successful. But where some seams thinned out, others 

 would come in, and therefore, in quarrying, or in mining by large exca- 

 vations, a tolerably uniform produce might, on the whole, be expected. 

 Mr. David Smith,* when examining the iron districts of Bengal, on 



hi- ^ o -ru, account of Government, endeavored to test the 



Mr. D. Smith's exa- ' 



mination. richness of the ironstone shales by sinking a pit f 



in the neighborhood of Badul (Barrool), to a depth of 52 feet, and in that 



*■ Mr. David Smith's Report to the Government of India on the Coal and Iron Districts 

 of Bengal. 1856. Mr. Smith does not appear to have been well acquainted with Mr. 

 Williams's previous work in the Raniganj district, nor to have understood (if he saw) the map, 

 in which the boundaries of the ironstone shales are laid down. Unfortunately these 

 boundaries have been marked in the map by white lines, indicating " dykes or faults," and 

 Mr. Williams's Report is difficult to understand without a very accurate knowledge of the 

 district. Mr. Smith's remarks on the area of the iron-producing strata show that be was 

 not aware of its extent, nor of the circumstance of the beds between Niamatpur and Taldanga, 

 being merely a continuation of those in the neighborhood of " Barrool" (Badul). He is 

 also, I think, in error in considering seams of ironstone as necessarily continuous throughout 

 the whole of the iron-shale area. These objections in no way detract from the value of Mr. 

 Smith's Report, which relates essentially to metallurgical and niineralogical, and not to 

 geological questions. 



•j- Marked in the Revenue Survey Map as a copper mine ! 



