236 Notes on the Geology of the Vicinity of Port Blair. [No. 3, 



commander of the Arracan, would have afforded me an opportunity, 

 had he not, on approaching, considered that owing to the surf 

 which was breaking on the steep cliffs, an attempt to do so would 

 have been attended with danger. 



The useful products contained in the rocks of the 

 Andaman Islands. 



So far as is at present known, the useful products occurring in the 

 rocks in the vicinity of Port Blair are chiefly confined to three, viz. 

 Coal, Serpentine and Sandstones suitable for building purposes : — 



Coal. — As has been mentioned above, traces of coal have been 

 found on Ross, at Navy point and at Viper. From all that I could 

 ascertain, the coal at each of these localities occurred in small nests 

 in the sandstones, which were speedily exhausted, and it was found 

 impossible to discover any definite seam which might be follow- 

 ed up. 



Instances of coal occurring in a similar manner are not wanting 

 in India as well as elsewhere. The principal localities are Cachar, 

 Chittagong, Cheduba Island, Sandoway, and some of the Southern 

 islands of the Nicobar group. The coal of these places has been 

 described as occurring in " nests of simply fossilized wood which 

 may be supposed to have drifted into the sandstones."* 



Regarding the quality of the coal which has been found, — two 

 specimens B and C, free from sandstone, have on analysis,! given 

 the following good results — 



Unpicked. Picked. 



A. B. C. 



Carbon, 50*8 52*3 62 



Volatile, 26- 41*4 34 



Ash, 23-2 6-3 4 



It is therefore a coal which would, undoubtedly, be of very great 

 value if found in large quantities for making gas ; possibly from its 

 lightness and consequent tendency to dissipate before complete 

 combustion had taken place, it might not prove of sufficient heating 

 power for steam engines. 



* Coal resources of India by T. Oldham, Esq., LL. D., 1867, p. 18. 



f By Mr. Tween. 



