308 Origin of I/lands. [Book VI. 



been thrown up by volcanic eruptions; and fome have 

 apparently been formed by that extraordinary infect 

 which produces rocks of coral. The iflands Delos 

 and Rhodes are faid to have grown out of the fea. 

 Pliny mentions a number of other iflands, which were 

 produced by fubterraneous fires. In 1628, one of the 

 iflands of the Azores rofe up out of the bottom of the 

 fea, which in that place was one hundred and fixty fa- 

 thoms deep ; and this ifland, which is three leagues 

 long, one league and an half broad, and three hundred 

 and fixty feet above the level of the water, rofe in fif- 

 teen days*. 



On the 2oth of November, 1720, a fubterraneous 

 fire burft out of the fea near Tercera, one of the 

 Azores, which threw up fuch a quantity of ftones, in 

 the fpace of thirty days, as formed an ifland two 

 leagues in diameter, and nearly circular f. 



The Ifle of Sheppey contains a great variety of 

 foffil bodies, as well animal as vegetable, which evi- 

 dently prove it to be an afiemblage of adventitious 

 matter. 



In every inftance upon record, the fragments of fea 

 {hells are infinitely more numerous than the bones and 

 teeth of fifh. The latter too are but feldom depo- 

 fited in any other matter than in beds of fand and gra- 

 vel, and not in the folid beds of Jime-ftone, as the 

 fhells of fifh generally are, even to the depth of many 

 hundred yards, and difpofed throughout the whole ex- 

 tent of the ftrata J. 



There is no occafion to fuppofe, that the whole 



* Sir William Hamilton's Obfervations on Vefuvius and 

 ./Etna. 



f PhSlofophical Tranfaftions, quoted by Whitehurft. 

 | Whitehurft, p. 44, 



furface 



