?4 ERA OF THE SUPERFICIAL FORMATIONS. 



inland. Then, upon another elevation, the sea began to 

 form, at its«new point of contact with the land, the third 

 highest beach, and so on down to the platform nearest to 

 the present sea-beach. Phenomena of this kind become 

 comparatively familiar to us, when we hear of evidence 

 that the last sixty feet of the elevation of Sweden, and 

 the last eighty-five of that of Chili, have taken place since 

 man first dwelt in those countries ; nay, that the elevation 

 of the former country goes on at this time at the rate of 

 about forty-five inches in a century, and that a thousand 

 miles of the Chilian coast rose four feet in one night, 

 under the influence of a powerful earthquake, so lately as 

 1822. Subterranean forces, of the kind then exemplified 

 in Chili, supply a ready explanation of the whole pheno- 

 mena, though some other operating causes have been sug- 

 gested. In an inquiry on this point it becomes of conse- 

 quence to learn some particulars respecting the levels. 

 Taking a particular beach, it is generally observed that 

 the level continues the same along a considerable number 

 of miles, and nothing like breaks or hitches has as yet 

 been detected in any case. A second and a third beach 

 are also observed to be exactly parallel to the first. 

 These facts would seem to indicate quiet elevating move- 

 ments, uniform over a large tract. It must, however, be 

 remarked that the raised beaches at one part of a coast 

 rarely coincide w T ith those at another part forty or fifty 

 miles off. We might suppose this to indicate a limit in 

 that extent of the uniformity of the elevating cause, but 

 it would be rash to conclude positively that such is the 

 case. In the present sea, as is well known, there are dif- 

 ferent levels at different places, owing to the operation of 

 peculiar local causes, as currents, evaporation, and the 

 influx of large rivers into narrow mouthed estuaries. The 

 differences of level in the ancient beaches might be occa- 

 sioned by some such causes. But, whatever doubt may 

 rest on this minor point, enough has been ascertained to 

 settle the main one, that we have in these platforms indu- 

 bitable monuments of the last rise of the land from the 

 sea, and the concluding great event of the geological his- 

 tory. 



The idea of such a wide- spread and possibly universal 

 submersion unavoidably suggests some considerations as 

 to the effect which it might have upon terrestrial animal 

 life. It seems likely that this would be, 01 such an occa- 



