1840.] 



of the Great Basaltic District of India. 



103 



ing these appearances, the character of the rock differed so much from 

 any varieties of basalt I had then seen in India, that I hesitated about 

 referring it to the trap family, till I had seen varieties of a red wacke 

 much resembling it, constituting part of the basaltic mountains of the 

 island of Salsette. It is in a substance of this kind, interstratified with 

 sandstone, that Tavernier describes the diamond mines of Beejapoor to 

 have been worked in former times. The transitory nature of the politi- 

 cal divisions of this part of India, and the decay or desertion of many 

 towns and villages, have hitherto prevented the identification of these 

 mines ; but enough has been said to show the importance of caution in 

 reasoning on individual facts, relative to one of the most singular and 

 extensive formations anywhere to be found. 



Note, 



The freshwater shells described in the preceding pages, must have in- 

 habited sheets of fresh water of which no traces can now be discovered, 

 in the configuration of the mountainous tracts, in which they for the 

 most part occur. No natural lakes exist in these districts, nor could 

 shells have accumulated in such quantity in rivers similar to those which 

 now intersect the country. It may, however, be supposed that the sand- 

 stone and limestone rocks of Berar had once a position similar to that 

 which the same rocks now occupy in the basins of the Kistnah and Pen- 

 nar. A'oysey describes these rivers as passing through the NuUa-MuUa 

 range by gaps or fissures " which have been produced by some great con- 

 " vulsion, which at the same time that it formed the beds of these rivers, 

 " gave passage to the accumulated waters of some vast lakes situated 

 " near the outlets." " The tortuous course of the Kistnah is bounded 

 " for upwards of 70 miles by lofty and precipitous banks, which in some 

 " places rise 1000 feet above its level, the opposite sides of the chasm 

 ** corresponding in an exact manner. Ravines of this description are not 

 " unfrequent all over the range, and the exact correspondence of their 

 ** salient and re-entering angles, together with the abruptness of their 

 ** origin, totally preclude the supposition of their being hollowed out 

 ** by the action of running water*." Such seems also to have 

 been the case, where the Pennar passes through a narrow gorge 

 in the Gundicottah sandstone hills. Through the upper part of 

 its course, this river flows over a flat country covered with 

 alluvial soil, at right angles to the hills ; but it fijids an exit 



• Asiatic Researches, vol, xv,, p. 183, 124. 



