1840.] 



On the Geology of Cntch. 



Uo 



thrown up by the earthquake, and covered the tract with fresh water, 

 or perhaps with fresh at its upper or northern extremity, and brackish 

 at its southern near the sea. Supposing this state of things to have re- 

 mained for some time, the river continuing to pour its water into this 

 lagoon, another change would take place in the description of the sedi- 

 mentary deposit. Once more the bunds were erected across the river, 

 the supply of fresh water ceased, and as that on the lagoon evaporated, 

 the sea again flowed in and converted it into a salt lake, which is its pre- 

 sent state. All the above changes are known to have occurred ; and 

 it is easy to suppose that if the shallow part at Sindoo were slightly rais- 

 ed above its present level, thus shutting out the sea, the part around 

 the Fort of Sindree would be converted once more into dry land. If, 

 therefore, at any future period, the river should again cut a channel, the 

 banks might present various, regular beds alternately enclosing marine 

 and freshwater exuviae, the latter being also associated with land 

 productions. 



The ruins of one of the towers of the Fort of Sindree remained, when 

 I visited Luckput in 1834, and in all probability now stand as a monu- 

 ment of the changes, which are daily taking place on the earth's surface. 



Conclusion. — In concluding this paper, I have only to observe, that I 

 have throughout endeavoured to describe facts as they appeared to me 

 at the time I examined them, without regard to any particular theory ; 

 and if 1 have failed in making my descriptions intelligible, I have only to 

 plead the difficulty of having had a great deal to describe in a limited 

 space. As the country to whieli this memoir relates is, however, unfor- 

 tunately from its geographical position, beyond the reach of general ob- 

 servers, I am induced to hope, that this sketch, however imperfect, may 

 be found to possess some interest. 



For the arranged list of fossil shells, given in the Appendix, as well as 

 for all my information on that subject, 1 am entirely indebted to Mr. 

 James De Carl Sowerby, w^ho had my specimens (now in the cabinets 

 of the Geological Society) for some time in his possession for examination. 



Note. — In conformity with our practice of extracting from scarce or 

 expensive works such articles on matters of Science connected with this 

 country, as appear in European Periodicals, we have taken from the 

 Transactions of the Geological Society of London the foregoing articles. 

 We wii^h we could give copies of all the figures of fossils which accom- 

 pany the original text, forming a most valuable addition to the palaeon- 

 tology of India, but their number precludes us from so doing— -the diffi- 

 culties andexpence attending the execution of so great a number of litho- 

 graphs being greater than the resources of thia Journal could meet, — 

 £d. Madras Joubnal. 



