16 V. Ball — Volcanos of the Bay of Bengal. 



II. — On the Volcanos of the Bay of Bengal. 



By V. Ball, M.A., F.G.S. ; 

 of the Geological Survey of India. 



(PLATE I.) 



DUKING the year 1873, it was my good fortune to be one of a 

 party who, in the course of an exploration of the Andaman 

 and Nicobar Islands, were enabled to spend a few hours on the 

 detached volcanic islands of the Bay of Bengal, which are known 

 respectively as Barren Island and Narkondam. The time at our 

 disposal did not admit of our making as thorough an examination as 

 we should have wished, but there was sufficient opportunity for 

 testing the accuracy of the statements regarding the islands which 

 had been previously published, and also for making a few original 

 observations. 



The information upon which the accounts of Barren Island, given 

 in geological manuals and other works, have been founded, is 

 exceedingly faulty. Dr. Liebig's paper, which contains the fullest 

 and most accurate description of the island, does not appear to 

 have reached the hands of several authors, who have since its 

 publication tenaciously clung to old statements which should have 

 been long since expunged. 



In presenting this account to the readers of the Geological 

 Magazine, it is necessary for me to premise that in substance it has 

 already been published in the Becords of the Geological Survey of 

 India. 1 The present edition differs from the original in being 

 illustrated by the accompanying sketches of the islands, and in 

 sundry small alterations and additions to the text. 



The wide circulation of the Geological Magazine among 

 geologists throughout the world affords an unequalled opportunity 

 for stamping out errors like those which are exposed in the follow- 

 ing pages. It is hoped that in future works and editions of works on 

 Geology or Volcanos there will be no repetition of the old statements 

 or old illustrations which have served to give such incorrect ideas 

 as to the physical features of these remarkable islands. 



Barren Island and Narkondam are two volcanic islands situated 

 in the Bay of Bengal at a distance of seventy miles from one another 

 on a north-by-east, south-by-west line. They constitute links which 

 connect what is known as the Molucca band with the volcanic region 

 of Arracan and Chittagong. This has been pointed out by several 

 physical geographers, one of whom 2 has written : — 



" One of the most terribly active groups of volcanos in the world 

 begins with the Banda groups of islands, and extends through the 

 Sunda groups of Timor, Sumbawa, Bali, Java, and Sumatra, 

 separated only by narrow channels, and altogether forming a gently 

 curved line 2,000 miles long ; but as the volcanic zone is continued 

 through Barren Island and Narkondam in the Bay of Bengal, and 



1 Calcutta, No. 4, 1873. 2 Mrs. Somerville. 



