148 Records of the Geological Survey of India. [vol. x. 
The failure, therefore, to produce good coke in the first experiments leaves little room to 
hope that such can be produced from any other Darjiling coal. 
With respect to the production of coke with the aid of pitch, taking into account, on the 
one hand, that coke made on the large scale yields better results than in mere crucible experi¬ 
ments, and on the other that the Tindharia coal possesses a slight tendency to cake per se, 
which some other of the Darjiling coals do not, it may perhaps be inferred that about a tenth 
or twelfth of pitch, or say 2j mans (mauuds) to the ton of coal is about the smallest propor¬ 
tion which would be found to answer in practice. The price of coal-tar pitch at the present 
time in Calcutta being Rs. 2-4 a man , this quantity would cost over six rupees at Sukna— 
that is to say, the pitch alone would cost nearly half the amount at which Raniganj coal 
could be delivered there per ton.* * * § 
The results of some experiments on a small scale, respecting the manufacture of 
patent fuel by agglutination with farinaceous matter, are mentioned in my report on 
Darjiling.t It yet remains to be proved, however, whether this plan would answer on a 
commercial scale. Attempts of this kind carried out at Raniganj, with the object of 
utilizing the small coal of the collieries there,J were successful in the production of good 
fuel, but not at a paying rate.§ 
Conclusion. Taking into account the extreme difficulty and corresponding expense 
which must be encountered in mining the Darjiling coal, and the subsequent expense of con¬ 
verting it into a usable form of fuel, I fear there is but little hope of working it at a rate 
less than, or even not exceeding, that at which Raniganj coal could he laid down at the foot 
of the hills. 
Assam coal .—In the coal of Assam, however, there is a supply which may eventually 
be found more advantageously available than either. If the projected communication should 
be established between tho Nazira coal-field and the Brahmaputra, and the branch line of 
the Northern Bengal Railway to Dubri be constructed, it is not improbable that coal taken 
down the Brahmaputra would command the market. Coke made from the strongly caking 
Assam coal mixed in due proportion with the anthacitie coal from Darjiling would probably 
be found (irrespective of cost) to yield a highly serviceable fuel, but the expense of manu¬ 
facturing it would most probably be found greater than the cost of delivering the raw 
Assam coal at the foot of the Darjiling hills. 
Limestones in the neighbottehood of Baeakak, by F. R. Mallet, F.G.S., Geological 
Survey of India. 
Not long ago, I had an opportunity of examining different deposits of limestone near 
the western border of the Raniganj coal-field, which have acquired additional importance of 
late owing to their employment as flux at the Barakar iron-works. In visiting the different 
quarries that have been opened, I had, as guide, an intelligent native employe, who was kindly 
sent with me for the purpose by the Manager of the Company. 
The most important localities—in fact the only ones in which limestone has been raised—- 
are two, namely, Baghmtira at the western end of Panchet Hill, and Hansapathar, ten miles 
* Memoirs, G. S. I., Vol. XI, p, 62. 
f Ibid, p. 60. 
t Records, Vol. VII, p. 162. 
§ This fact in itself alone, however, cannot he taken as conclusive against the production of similar fuel in the 
Darjiling district. At R&niganj, patent fuel must hold its own against round coal raised on the spot, whereas in 
the Darjiling district it would have the advantage of competing with round coal brought from long distances. 
