Masterpieces of Science 



other place, the continuous deposition of river 

 mud and sand, such as the Ganges and Brahma- 

 pootra have poured for thousands of years into 

 the Bay of Bengal. Part of this bay, although 

 of considerable depth, might at length be filled 

 up before an appreciable amount of change was 

 effected in the fish, mollusca, and other inhabi- 

 tants of the sea and neighbouring land. But if 

 the bottom be lowered by sinking at the same 

 rate that it is raised by river mud, the bay can 

 never be turned into dry land. In that case one 

 new layer of matter may be superimposed upon 

 another for a thickess of many thousand feet, 

 and the fossils of the inferior beds may differ 

 greatly from those entombed in the uppermost, 

 yet every intermediate gradation may be indi- 

 cated in the passage from an older to a newer 

 assemblage of species. Granting, however, that 

 such an unbroken sequence of monuments may 

 thus be elaborated in certain parts of the sea, 

 and that the strata happen to be all of them well 

 adapted to preserve the included fossils from de- 

 composition, how many accidents must still 

 concur before these submarine formations will be 

 laid open to our investigation ! The whole de- 

 posit must first be raised several thousand feet 

 in order to bring into view the very foundation; 

 and during the process of exposure the superior 

 beds must not be entirely swept away by denu- 

 dation. 



In the first place, the chances are nearly as 

 three to one against the mere emergence of the 

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