Ball — On the Volcanoes and Hot Springs of India. 155 



Passing now to more recent scenes of volcanic activity, there are 

 two islands, and possibly a submerged third, which claim attention as 

 being of purely volcanic origin, one of them, moreover, having been 

 in a condition of violent eruption within historical times. Of these 

 I have published descriptions already,' and subsequently they were 

 exhaustively surveyed and described by Mr. F. E. Mallet and Captain 

 Hobday.^ 



Here it is only necessary to make a very short reference to them. 

 The more northern of them is now called Narcondam ; it is situated in 

 lat. 13° 26', long. 94° 15', is 2330 feet high, and 2^ miles in diameter. 

 It consists mainly of a mass of hornblendic andesite, and there being 

 no signs of a crater or of any alternations of lava and ash, it has been 

 suggested by Mr. Mallet that it owes its origin to the " extrusion of 

 viscid lava without the accompaniment of crater-forming materials," 

 thus resembling in its origin the " domite" of the Puys of Auvergne. 



Colonel Yule has suggested that the name may have been derived 

 from two Sanskrit words, Naraha hondam^ signifying a pit of hell, a 

 not very appropriate title under the circumstances, because there is 

 no crater and no historical record of any volcanic eruption having ever 

 been observed in connection with the island ; but passing to the other 

 volcano, which is now called Barren Island, we there find, in lat. 

 12° 15', long. 93° 50' a perfect crater with central cone, rising respec- 

 tively to 1100 and 1000 feet, and of this volcano, which is now 

 quiescent, we have abundant evidence that towards the close of the 

 last century and beginning of this, i.e. from 1789 to 1804, it was 

 in an active state of eruption. 



Mr. Mallet, however, in searching old charts of the bay of Bengal, 

 came to the conclusion that the name of Narcondam may originally 

 have been applied to it before it received its English title of Barren 

 Island, and hence we can see reason for accepting the title "A pit 

 of hell " as having possibly been conferred by native navigators to this 

 basin-like crater from the centre of which the usual volcanic pheno- 

 mena were at the time being manifested. (I exhibit a photograph 

 which shows how appropriate such a name would have been for Barren 

 Island.) 



On the same line of volcanic activity, further south, there is a reef 

 which may possibly indicate the position of a third volcano. 



1 Geological Magazine, vol. vi., 1879, pp. 16-27, and Id., Decade III., vol. v., 

 1888, No. 9, p. 404; and recently Id., Decade III., vol. x., 1893, No. 349, 

 p. 289, with Plate. 



^ Mem. Geol. Surv. of India, vol. xxi., part 4. 



M 2 



