DOMAIN XII. VOLCANIC. 



pent in a narrow passage, are able to raise up a 

 mass of earth as large as an island ; but that this 

 should be done in so regular and exact a manner, 

 that the water of the sea should not be able to 

 penetrate and extinguish these fires ; and after 

 having been extinguished, that the mass of earth 

 should not fall down, or sink again with its own 

 weight, but still remain in a manner suspended 

 over the great arch below 1 This is what to me 

 seems more surprising than any thing that has 

 i been related of Mount Etna, Vesuvius, or any 



other volcano.'* 



of Ordinaire estimates the number of volcanoes on 

 )es * this globe, in actual activity, at^one hundred and 

 eighty-nine ; of which ninety-nine are on conti- 

 nents, and ninety in islands. But if we reflect on 

 the vast portions of the earth which are still un- 

 explored, particularly the interior of Africa, and 

 of Notasia, it will not be thought rash, if the whole 

 be estimated at two hundred and fifty ; though in 

 strict argument this number should be diminished, 

 and not enlarged. 



Extinct Nor will the candid inquirer reject the suppo- 

 s j^j on o f a vast num ber of volcanoes now extinct. 

 Vesuvius itself has repeatedly been in this situa- 



* Payne's Geogr. Extracts, p. 252; 



