CORAL-REEFS. 185 



volcanic outburst, and we may feel sure, that this sinking 

 must have been immense in amount as well as in area, 

 thus to have buried over the broad face of the ocean every 

 one of those mountains, above which atolls now stand like 

 monuments, marking the place of their former existence. 

 Reflecting how powerful an agent with respect to denu- 

 dation, and consequently to the nature and thickness of 

 the deposits in accumulation, the sea must ever be, when 

 acting for prolonged periods on the land, during either its 

 slow emergence or subsidence ; reflecting, also, on the final 

 effects of these movements in the interchange of land and 

 ocean-water on the climate of the earth, and on the dis- 

 tribution of organic beings, I may be permitted to hope, 

 that the conclusions derived from the study of coral- 

 formations, originally attempted merely to explain their 

 peculiar forms, may be thought worthy of the attention of, 

 geologists. 



