22 RANIGANJ COAL FIELD. [CHAP. I. 



5th. — The occurrence of the great band of carbonaceous shales, 

 containing ironstones, and their position in the series, was determined. 

 The " greenish-grey shales" of the Talchir group were noticed, as 

 also their absence in the North-eastern portion of the field. 



But, on the other hand, several important geological facts were left 

 Questions left unde- undetermined. The greenish-grey shales and 

 conglomerates, (now recognized as belonging to 

 the Talchir group,) and the beds containing red marls, (here described 

 as the Panche't group,) were observed, but were not'separated from the 

 other rocks, sufficient importance not having been attached to the 

 evidence of their unconformity with the true Damuda series. The 

 separation caused in the general series by the band of ironstone shales 

 was not given sufficient prominence, and the beds of Raniganj and of 

 the Singharun Valley were entirely misplaced. Mr. Williams was also 

 led by his English experience erroneously to anticipate that faults would 

 be found co-existent with trap dykes, and that the coal seams would be 

 found equally co-extensive with the beds accompanying them. The 

 map is also erroneous in representing Panche't (Pachete), Beharinath, 

 Garangi, and Telinda or Madjia Hills, as gneiss. The boundaries 

 generally required greater exactitude. But such detailed errors of 

 mapping are more than excused by the difficulties under which he 

 labored. No topographical map of the country existed : that published 

 was laid down during the progress of Mr. Williams's survey, and the 

 geological work was frequently in advance of the topographical, and 

 had to be put on paper subsequently. 



As regards the geological relations of the beds of the Damuda 

 field with those in Europe, Mr. Williams appears never to have 

 doubted that all the Indian coal-bearing strata belonged to the same 

 age as the carboniferous formation of European geologists. One or 

 two extracts have already been given. The following, however, appear 

 conclusive. 



