590 



GEOGKAPHICAL BOUNDARIES 



[Ch. XXIII. 



beds, and they show that there has been a general elevation 

 of these islands at a comparatively modern period."* 



The same linear arrangement which is observed in Java 

 holds good in the volcanos of Sumatra, some of which are of 

 great height, as Berapi, which is more than 12,000 feet above 

 the sea, and is continually smoking. Hot springs are abun- 

 dant at its base. The volcanic line then inclines slightly to 

 the north-west, and points to Barren Island, lat. 12° 15' N., 

 in the Bay of Bengal ; a volcano often observed to emit 

 smoke and vapours, and from which lava has proceeded since 



). The volcanic train then 



1790 



XXVII.). 



\ Macclelland 



N 



om 



a burning mountain. 



signs of lava currents descending from the crater to the base. 

 Afterwards the train stretches in the same direction to the 

 volcanic island of Eamree, about lat. 19° N., and the adjoin- 

 ing island of Cheduba, which is represented in old charts as 



Thus we arrive at the Chittagong coast, 

 which in 1762 was convulsed by a tremendous earthquake 



(see Chap. XXX.). t 



To enumerate all the volcanic regions of the Indian and 



Pacific oceans would lead me far beyond the proper limits of 



this treatise ; but it will appear in the last chapter of this 



work, when coral reefs are treated of, that the islands of 



the Pacific consist alternately of linear groups of two classes, 



the one lofty, and containing active volcanos, and marine 



strata above the sea-level, and which have been undergoing 



upheaval in modern times ; the other very low, consisting of 



reefs of coral, usually with lagoons in their centres, and in 



which there is evidence of a gradual subsidence of the 



ground. The extent and direction of these parallel volcanic 



bands has been depicted with great care by Darwin in his 



map before cited (p. 387). 



The most remarkable theatre of volcanic activity in the 



Northern Pacific — or, perhaps, in the whole world — occurs 



* Paper read at meeting of Brit. 

 Assoc. Southampton, Sept. 1846. 



t Macclelland, Keport on Coal and 

 Min. Eesources of India. Calcutta, 1838. 



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