76 Volcanic bands extending [3at$, 



miscuous nature of volvanie action, and may have tended materially to 

 embarrass the views of geologists in districts not calculated to afford any 

 very striking results. 



If we refer to the volcanic belt of the Molucca and Sunda islands, 

 we shall mid evidence of as perfect a lineal tendency in the direction 

 of its active energies as that which the extinct band affords, of having, 

 within the secondary period, extended across the centre of India in a 

 line parallel with the equator from the gulf of Cumbay to the Hima- 

 laya. 



The active vents of the Molucca band have been extended by Von 

 Buch from Sumatra to Barren Island, from which point the train 

 may be carried in the same line through the islands of Narcandam and 

 Rambree, to the coast of Arracan and Chittngong, as represented on 

 the annexed map ; at this situation the two zones intersect each other, so 

 as to form their united focus in the Kdsya mountains where the energies 

 of both would seem to have been most exerted, the elevatory move- 

 ments having commenced in the secondary, and continued throughout 

 the tertiary period. 



Although oscillations of the surface, and perhaps occasional eruptions 

 may have taken place at all times, attended by the subsidence of one 

 tract, and the upheavement of another, yet the principal energy of the 

 Vindhya* volcanic belt from A to B, appears as already stated to have 

 been chiefly confined to the secondary period. 



A chain of sienite passing on the one hand into granitic rocks, chiefly 

 composed of felspar, and on the other into greenstone and basalt, extends 

 across this portion of the continent. On the flanks of this chain the 

 coal measures repose, rarely forming a series of beds so extensive as 

 observed in England, except perhaps in the Caribari hills and along 

 the southern boundary of Assam. A sandstone equivalent to the old 

 red, rests immediately on the disturbed strata ; with the sandstone, beds 

 of coal and shale, as well as limestone occur : along the flanks of the 

 chain thermal springs are situated, one of these has been recently found 

 by Mr. Betts in the Damuda river near the foot of the Pachite hillsf . 

 In the Nerbudda valley two have also been brought to notice by Dr. 

 Spilsbury ; in Curruckpore district several hot springs are mention- 



* Such is the geographical name of the range which extends from the Gulf of 

 Cambay to the Ganges at Bdgalpore, from which it would seem from certain 

 indications (24.49) to have been extended by a series, obliterated ridges across 

 the Delta to the Garrow mountains, the leading geological features of the older 

 rocks being, as far as they are as yet determined, the same on both sides (41.) 

 f Journ. As. Soc. 1833-36. 



