16 RANIGANJ COAL FIELD. [CHAP. I. 



" thickness from a few inches to about three feet, and the greatest 

 " number of beds found in a single coal field has not exceeded two or 

 " three at the utmost. In the Damoodah Valley it will be shown that 

 te beneath the black and grey argillaceous shales previously adverted to, 

 " there is a considerable deposit of coal-bearing measures, principally 

 " composed of sandstones and conglomerates, subordinate beds of shale, 

 " seams of coal, and thin beds of argillaceous limestone, resembling in 

 " mineral character the nodular limestone of the lias, but these calca- 

 " reous accumulations appear to be devoid of organic remains." 



A measured section of 4,097 feet, embracing the lower 1,000 feet of 

 the iron shales, all the lower coal-bearing series, and the Talchir group 

 (see below) is given to show the constitution of the lower measures, and 

 a detailed account of eighteen coal seams contained in them follows. x\ 

 great portion of this section was deduced from a series of pits sunk 

 by Mr. Williams in the neighborhood of Taldanga. Of the eighteen 

 coal seams only four are stated to be composed of superior coal. 



Mr. Williams here enters into the question, whether the "lowest 

 coal-bearing strata" (of the Damtida field) should be placed on the 

 parallel of the millstone grit (of England), or one step higher in the 

 series. With regard to this subject the following is worthy of extrac- 

 tion, as showing what opinion he held upon the subject: — 



" The great difference existing between these shales and those of 

 " England, is simply this : there they contain all the productive beds 

 " of coal commonly developed in the rock termed lower-measures ; 

 " and in the Damoodah the lowest coal seams are developed in the rocks 

 " inferior in position, and have a greater thickness than the whole 

 " quantity contained in the great coal field of South Wales. With this 

 " anomaly, together with the absence of the carboniferous limestone, 

 " it must be confessed that it is no easy question to decide a point of 

 " so much scientific importance. It would seem premature in the 

 " present state of the investigation to arrive at a definite conclusion, or 



