Mr. Dakwin has uo admissible rcason for commencing this 

 discussion at the shores of America. The chart of the ocean 

 between these and the easteru shores of Asia, shows, that 

 the comraencement of the subterranean , or submarine , or sub- 

 crustean action, by wliich the ludonesian and Polynesiau 

 components were produced, commenced not at the former, about 

 four thousaud miles distant from the islands of Eastern Poly- 

 nesia, but at the latter, not so many hundred miles dis- 

 taut, and thence proceedüd eastward, gradually aiminishing in 

 power after the miited action of the two lines, hereafter to be 

 mentioned, had become weakened, until it ceased to eastward 

 of the Marqaesas and liow Islaud (or Dangerons) Archipelago. 

 The absence of islands on the vast expanse of ocean between 

 the west coast of America and Eastern Polynesia shows, that 

 with the exception of the Gallapagos, Juan Eernandez and 

 two or three other small isles, whicli, lying near to that coast, 

 have doubtless been produced by the subterranean action deve- 

 loped along the western side of that continent, and which was 

 distinct fiom that, which produced the components of Polynesia 

 as well as of Indouesia; the subterranean action which pro- 

 duced Australia and Tasmania was also distinctfrom both,altho' 

 probdbly all were exerted contemporaneously or nearly so. We 

 now proceed to show, that Mr. Dakwin's assertions and infe- 

 rences are both alilce erroneous and untenable, as also, that 

 the supposition proposed in paragraph III, respecting the origin 

 of encircling recfs, not on!y aftbrds a more probable account 

 of these, but also of the elevation and composition of the en- 

 circled islands, which Mr. Dakwin has not ventured. to at- 

 tempt accounting for, altho' evidently not subsiding ones, as ap- 

 pears from his own description of Otaheite, and ensuite we shall 

 suggest a theory, respecting the origin of lagoon islands much 

 more probable than his. But we must deal with his statements 

 seriatim before going elsewhere. Eirstly. It is not true, that 

 no marks of elevation exist among the islands lying within the 

 vast extcnt, which he says, must be admitted as being an area 

 of sudsidcncc, as vide the following facts. 



