Indian Science and Technology in the Eighteenth Century: Some Contemporary European Accounts c12.17

c12.17

P.S. There is an observation perhaps worth remarking with respect to the change of the Poles; namely, that the small rock oysters are generally all dead within about a foot above high water mark; now possibly naturalists may be able to tell the age of such shells nearly by their appearance, and if so, a pretty good estimate may be formed of the rate of alteration of the level of the sea in such places where they are; for I made some astronomical observations on a rock in the sea near an island about seven miles to the south of the island of Cheduba on the Aracan coast, whose top was eighteen feet above high water mark, and the whole rock covered with those shells fast grown to it, but all of them dead, except those which were a foot above the high water mark of that day, which was February 2, 1788: the shells were evidently altered a little in proportion to their height above the water, but by no means so much as to induce one to believe that the rock had been many years out of it: all the adjacent islands and the coast showed similar appearances, and therefore it was evidently no partial elevation by subterranean fires, or any thing of that sort: this is also apparent from the island of Cheduba itself, in which there is a regular succession of sea beaches and shells more and more decayed to a great height. By a kind of vague estimation from the trees and the coasts and shells, & c. (on which however there is not the least dependence) I supposed that the sea might be subsiding at the rate of about three inches in a year.