COAL.
Stinkull, . . . . DAN. Carvoes de retire, . PORT, Steenkoolen, . . Dcr. Carvoes de terra, Steenkull, . . Ugolj, Kamenoe, 'tug.
Charbon de terre, . . Carbones du tierra, . SP.
Steinkoblen, . . GER. piedra, . Valaiti kuela, . . 01L1. Stenkol, Sw.
Carboni fossili, . . IT. Simai Kai ri, . . TAU. Arang-tanah, . MALAY. sima Boggu, . . Tst..
Coal differs considerably in its physical pro perties, and its varieties obtain various names in the markets. The mineralogist generally classes it as coal. without bitumen, and coal with bitumen. The first variety is known by the general name of anthracite. It is soinetitnes very hard, .has a high lustre, and is often iridescent. It is used for fuel, but it is often made into small inkstands, boxes, and other articles of use. This is more especially the case with the anthracite of America. Anthracite is the most common form of coal hi the Welsh beds. The kinds are known in com merce as splint, caking, cherry, cannel, and brown or wood coals, also lignite and jet.
Coal was worked in Bengal in 1774 by Messrs. neatly and Sumner of the Bengal civil service, who obtained a monopoly. Their operations were in the Raniganj coal - field, but they found it unprofitable, and the mines remained unworked till 1815, when Mr. Jones commenced operations. He too was unsuccessful ; and in 1820 Messrs. Alexander & Co. undertook them. From that date collieries increased in nutnber ; and in 185'J so many as fifty were at work, employing 27 steam-engines, producing then 304,094 tons of round coal. During 1878 and 1879, in the Rani ganj fields, 388,931 men and 196,627 women, with 27,277 children, were supported by mining opera tions, the out-turn of coal being 528,001 tons (Tr. of Hind. i. p. 170). The quantity of coals brought clown in 1840 wa.s about 15 lakhs maunds. In 1850 it was nearly its double, and in 1860 it had become its quadruple. The supply and the consumption of coal in India during ten years WR.S as under, in =ands of 80 lbs.: Of the coal raised in 1868, almost the whole was from the Raniganj field. One-half of the supply
was consumed by the East Indian Railway, and was used for locomotives RS far as Ambala.
Coal of British India occurs in the lower Gondwana system, palmozoic rocks, in which three series have been recognised, viz., Damuda, Ranigauj, or Kamthi.
6) Ironetoni,s, shales, and Varakar, c) Knrharbari anti Talchir.
The Karharbari group yield coal, but, except in some of the eastern fields of the Damuda valley series, the Barakar group includes all the valuable coal of Peninsular India. In the Jhariah coal-field its thickness is estimated at 3800 feet, and at Raniganj 2000 feet.
The Raniganj group consist of sandstones, car bonaceous shales, and coal. The coal is of good quality, and comparatively uniform in composition and in the closeness of it seams.
In the rocks of the Kamthi group coal rarely occurs.
The areas of the 37 separate Indian coal measures aud associated younger rocks, which may conceal coal-measures, have been drawn up by Mr. IIughes as under, total 35,000 sq. tn.: Godavery and sq. m. Nerbadda and sq. m.
affluents, . . . 11,000 affluents, . . . 3,500 Sone, . . . . . 8,000 Damuda, 2 000 Sirguja and Orissa, 4,1)00 Rajmahal area, . . 300 Assam, . . . . 3,000 Unsurveyed, etc., . 2,700 The rocks which in Peninsular India probably correspond, as regards the time of their formation, to the true carboniferous rocks of Europe, are not coal-bearing ; and the oldest coal-measures iu British India belong to a period which is well included within the limits of the upper palmozoic or permian and the lower jurassic formations.
The separate coal-fields are : (a) North of Darnuda river, in Bengal, viz. Birbhum, Deogarli, Karharbari, and Rajmahal bills.
(b) Damuda valley, viz. Bokara, Jbariah, N. and S. , Karanpura, Ramgarh, and Raniganj.
(c) West of Damuda valley, viz. Aurunga, Chopti, Daltonganj, Hutar, and Itkuri.
(a) Sone and Mahanadi valleys, viz. I3isrampur, .Thilmilli, Lakhanpur, Raigarh, and Hingir ; Rampur, S. Rewa and Sohagpur ; lIdaipur and Korba, Tattapani; and in Orissa, Talchir.