8 HAMaumi coal-field. 



possessed. The manner of its occurrence in this field tends further to 

 endorse the truth of the theory now pretty well established of its being- 

 a shore deposit. 



The characters which it exhibits and which separate it from all the 

 other rocks of the series, indicate the presence, at 

 the time of its formation, of certain conditions 

 which were not continued throughout the period. These conditions were 

 the existence of boulders and weathered masses of gneiss, the accumula- 

 tion of ages, which formed a talus resting on the flanks of the metamor- 

 phic hills. Upon this talus, as the waters advanced over the sinking sur- 

 face, silt was gradually deposited; and when it was covered up, the 

 formation of silt-shales and sandstones proceeded without interruption ; 

 the hills still forming islands, or in the case of ranges, the boundaries of 



estuaries.* 



III. — Damuda Series. 



Section I. The Baeakau group. — Resting unconformably upon 

 the Talchirs, as we have shown, are found the rocks which con- 

 stitute the Bardkar group. The lowest beds 

 — those either immediately above the Talchirs 

 or else over-lapping on to the gneiss, are most frequently pebbly con- 

 o-lomerates, in some few places however we find whitish, often false- 

 bedded, argillaceous sandstones at the base. Again there are rocks 

 occurring at certain junctions, whose lithological characters are inter- 

 mediate between those of Talchirs and Bardkars ; these are of unimport- 

 ant extent and thickness, and never involve a question of more than a 

 few feet. 



* In parts of the adjoining district of Maunbhooui, considerable deposits of allu- 

 vium occupy many of the valleys. I have occasionally found in this alluvium badly deve- 

 loped boulder-beds ; but where we wovdd naturally look for the best developed examples, 

 viz., at the foot of the hills, we are hindered by the want of sections sufficiently deep. 

 The' general appearance of this deposit is such as to force^ on any observer's mind the 

 conviction that the conditions which existed during the Talchfr period have been repeated 

 in comparatively recent times. At the present day tliere is a talus at the foot of many of 

 the hills, which, if the country were again submerged, would furnish the principal materials 

 of a very considerable bouldcr-bed. 



( 116 ) 



