Changes of Level in the Pacific Ocean. 249 



apparent that in many cases islands now disjoined have been 

 once connected, and thus several atolls may have been made 

 about the heights of a single subsiding land of large size. 

 Such facts shew farther error in the above estimate, evin- 

 cing that the scattered atolls and reefs do not tell half the 

 story. Why is it, also, that the Pacific Islands are confined 

 to the tropics, if not that beyond thirty degrees the zoophyte 

 could not plant its growing registers \ 



Yet we should beware of hastening to the conclusion that a 

 continent once occupied the place of the ocean, or a large 

 part of it, which is without proof. To establish the for- 

 mer existence of a Pacific continent is an easy matter for the 

 fancy ; but geology knows nothing of it, nor even of its pro- 

 bability. 



The island of Banabe, in the Caroline Archipelago, affords 

 evidence of a subsidence in progress, as my friend, Mr 

 Horatio Hale, the philologist of the expedition, gathered from 

 a foreigner who had been for a while a resident on this island. 

 Mr Hale remarks, after explaining the character of certain 

 sacred structures of stone, " It seems evident that the con- 

 structions at Ualan and Banabe are of the same kind, and 

 were built for the same purpose. It is also clear that when 

 the latter were raised, the islet on which they stand was in 

 a different condition from what it now is. For at present 

 they are actually in the water ; what were once paths are 

 now passages for canoes, and as O'Connell (his informant) 

 says, ' w r hen the walls are broken down the water enters the 

 enclosures.' " Mr Hale hence infers, " that the land, or the 

 whole group of Banabe, and perhaps all the neighbouring 

 groups, have undergone a slight depression." He also states 

 respecting a small islet near Ualan, ci from the description 

 given of Leilei, a change of level of one or two feet would 

 render it uninhabitable, and reduce it, in a short time, to the 

 same state as the isle of ruins at Banabe." 



Period of the subsidence. — The period during which these 

 changes were in progress, was probably since <the tertiary 

 epoch. In the island of Metia, elevated over two hundred 

 feet, the corals below were the same as those now existing, 

 as far as we could judge from the fossilized specimens. At 



