1870.] Notes on the Geology of the Vicinity of Port Blair. 237 



So far as they have been examined, the Nicobars and Andamans 

 do not contain any trace of the group of coal bearing rocks (Eocene) 

 to which, according to Dr. Hochstetter, the workable coal 

 seams of Java, Borneo and Sumatra belong. 



Serpentine. — The Serpentine near Homfray's ghat, the ex- 

 istence of which was first pointed out by Mr. K u r z* is, I think, 

 deserving of special mention in an account of the useful products. 



This Serpentine marble is an exceedingly handsome variegated 

 green and black rock, which might be worked up into many useful 

 and ornamental articles. The portion exposed near the surface is 

 of very variable quality, and is much broken up. Lower down, how- 

 ever, where the rock has been protected from the injurious effects 

 of the atmosphere, it might be found to be of a more uniform char- 

 acter. 



If on quarrying it should be ascertained that large blocks of 

 homogeneous texture can be obtained, there can be no question 

 that the working up of such a stone would furnish an occupation 

 singularly well suited for those amongst the convicts whose consti- 

 tutions unfit them for laborious out-door work ; while it is con- 

 ceivable that under judicious management, it might be made a very 

 profitable undertaking. 



Manufactures of more or less elaborate character in soft sectile 

 stones, such as soap stone and marble supply, as is well known, oc- 

 cupation and the means of living to large numbers of people in 

 parts of the North West Provinces, in Chota Nagpur, and other 

 parts of India and in Burma. 



It is not improbable that amongst the convicts some might be 

 found already skilled in such work. In any case were the opera- 

 tions at first simply confined to sawing the rock into slabs, such 

 would, I believe, find a ready sale, and be applicable to many of the 

 purposes for which Italian marble is largely imported into Calcutta. 



Building Stones. — Sandstones are found on all the small islands 

 and on the so-called mainland in the vicinity of Port Blair. The 

 variation in texture is not excessive. The sandstones of Ross have 

 been used extensively in the buildings on that island, and have 

 I believe been found when carefully selected, very strong and 



* Eeport on the Vegetation of the Andamans. 



