Analysis of Indian^ Chinese, and New Holland Coals. 347 



offered in payment. A large heap was thus accumulated ; and 

 as the island abounds in this mineral, and there are no padlocks 

 upon the mines, as in Cumberland, it might soon effectually de- 

 stroy the income of the Borrowdale Company, if introduced 

 largely into the English market. The natives of Ceylon make 

 no use of it. 



Analyses of several Indian, Chinese, and New Holland Coals. 

 By J. PRINSEP, Esq. Secretary to the Physical Class of the 

 Asiatic Society of Calcutta. 



A HE following table, published in the Calcutta Gleanings of 

 Science, comprises the results of several analyses of Asiatic and 

 New Holland coals. The fourth column, containing the water 

 expelled, is kept distinct from the three which follow it, under 

 the head of composition, as it is usual to include all the volatile 

 products together. Should the water be looked upon as hygro- 

 metric, the per-centage of carbon and ashes must be increased 

 to obtain the true composition of the coal : thus the Baghelpur 

 slate-coal, after deducting 10 per cent, of water, contains 



Volatile matter, 22 x Vb" = 24.4 

 Carbon, . . 40.5 x do. = 45.0 

 Ashes, . . . 27.5 X do. = 30.6 



100.0 



From the last column in the table, it will be seen how totally 

 unfit are most of the Indian coals for the purpose of making 

 coke. The Burdwan coke, with the exception of one specimen, 

 would contain nearly a quarter of its weight of earthy impurity ; 

 the Silhet would be still worse ; the anthracite of Baghelpur 

 would be nearly half earth '; some of the mountain coal from 

 Ava would yield a coke of better quality, but of very little den- 

 sity. The Chinese glance-coal alone forms a remarkable ex- 

 ception to this unfavourable conclusion against oriental coal, 

 and deserves to rank at the head of the list in respect to its pu- 

 rity as a coke, although in specific gravity it does not come up 

 to the character of the English fuel, neither has it the spongy 

 texture which must contribute much to the glowing combustion 

 of the latter. It will be remarked, that the ashy residue on the 



