462 The Geological Survey of India. [Oct., 



of sandstones, &c, associated with the coal in Bengal and those of 

 Central India. The vast extension and great constancy in mineral 

 character of the Talchir rocks (which form the base of the great 

 coal-hearing series) have been fully established, and the thinning 

 out of the beds in passing to the west has received further support. 

 The entire Coal-formation, which in the east gives five well-marked 

 subdivisions (in ascending order, Talchir, Barakar, Ironstone shales, 

 Eanigunj, and Panchet), becomes, at a short distance to the west, 

 only a threefold series, comprising the Talchir, Barakar, and Panchet 

 subdivisions. Additional proofs have been brought forward to show 

 that on the large scale, the present limits of these Coal-measures 

 coincide approximately with the original limits of deposition, and 

 are not the result of faulting, or even mainly of denudation. 



And Dr. Oldham expresses his opinion that the great drainage 

 basins of India were on the large scale marked out, and existed (as 

 drainage-basins) at the enormously distant period which marked the 

 commencement of the deposition of the great plant-bearing series. 

 In this point of view, local variations in the lithological type, local 

 variations in the thickness of the groups, and even their occurrence 

 or non-occurrence, are only necessary consequences of the mode and 

 limit of formation. 



In 1861 Dr. Oldham gave a summary statement of the amount 

 of coal raised throughout India for the past three years, which was 

 about 850,000 tons. The total amount of coal raised in India gene- 

 rally was, in 1858, about 226,140 tons; in 1859, about 347,227 tons; 

 and in 1860, about 370,206 tons. Of this quantity the Eanigunj 

 field yielded by far the greater part. The only mode of transport, 

 however, from this field was by the river Damuda, a stream only 

 navigable during the freshes of the rainy season, after which it be- 

 comes so dry that no more coal can be sent to market until the 

 next season. 



In 1867 Dr. Oldham made a report on the Coal-resources of 

 India* The extensive fields which occur are not distributed gene- 

 rally over the country, but are almost entirely concentrated in one, 

 a double, band of coal-yielding deposits, which with considerable 

 interruptions extends more than half across India, from near 

 Calcutta towards Bombay. 



Little more than surface workings are carried on — the deepest 

 pits scarcely exceed 75 yards, while certainly one-half of the Indian 

 coal which has been used up to the present date has been produced 

 from open workings or quarries. 



Dr. Oldham concludes that out of the whole series of Indian 



coals, the very best of them only reach the average of English coals, 



and that on the whole they are very inferior to them. It should, 



however, be borne in mind that until all the fields are carefully 



* Being a return called for by the Eight Hon. the Secretary of State for India. 



