242 COSMOS. 



self tlie history of ail islands of elevation. For upward of 

 2000 years, as far as history and tiadition certify, it would 

 appear as if nature were striving to form a volcano in the 

 midst of the crater of elevation."* Similar insular eleva- 

 tions, and almost always at regular intervals of 80 or 90 

 years,t have been manifested in the island of St. Michael, in 

 the Azores ; but in this case the bottom of the sea has not 

 been elevated at exactly the same parts. $ The island which 

 Captain Tillard named Sahrina, appeared unfortunately at 

 a time (the 30 th of January, 1811) when the political rela- 

 tions of the maritime nations of Western Europe prevented 

 that attention being bestowed upon the subject by scientific 

 institutions which was afterward directed to the sudden ap- 

 pearance (the 2d of July, 1831), and the speedy destruction of 

 the igneous island of Ferdinandea in the Sicilian Sea, between 

 the limestone shores of Sciacca and the purely volcanic island 

 of Pantellaria.§ 



and partly of erupted matter — erupted, however, beneath the surface 

 of the water."] — Tr. 



* Leop. von Buch, Physik. Bcsckr. der Canar. Inseln, s. 358-358, 

 and particularly the French translation of this excellent w^ork, p. 402 ; 

 and his memoir in Poggendorf's Annalen, bd. xxxviii., s. 183. A sub- 

 marine island has quite recently made its appearance within the crater 

 of Santorino. In 1810 it was still fifteen fathoms below the surface of 

 the sea, but in 1830 it had risen to within three or four. It rises steeply, 

 like a great cone, from the bottom of the sea, and the continuous ac 

 tivity of the submarine crater is obvious from the circumstance that sul 

 phurous acid vapors are mixed with the sea water, in the eastern bay 

 of Neokaimeni, in the same manner as at Vromolirani, near Methana. 

 Coppered ships lie at anchor in the bay in order to get their bottom? 

 cleaned and polished by this natural (volcanic) process. (Virlet, in the 

 Bulletin de la SociHi Giologique de France, t. iii., p. 109, and Fiedler, 

 Reise durch Griechenland, th. ii., s. 469 and 584.) 



t Appearance of a new island near St. Miguel, one of the Azores, 11th 

 of June, 1638, 31st of December, 1719, 13th of June, 1811. 



X [My esteemed friend. Dr. Webster, professor of Chemistry and 

 Mineralogy at Harvard College, Cambridge, Massachusetts, U. S., in 

 his Description of the Island of St. Michael, ^c, Boston, 1822, gives an 

 interesting account of the sudden appearance of the island named Sa- 

 brina, which was about a mile in circumference, and two or three 

 hundred feet above the level of the ocean. After continuing for some 

 weeks, it sank into the sea. Dr. Webster describes the whole of the 

 island of St. Michael as volcanic, and containing a number of conical 

 hills of trachyte, several of which have craters, and appear at some 

 former time to have been the openings of volcanoes. The hot springs 

 VFhich abound in the island are impregnated with sulphureted hydro 

 gen and carbonic acid gases, appearing to attest the existence of vol 

 canic action.] — Tr. 



^ Prevost, in the Bulletin de la Soci6ti Giologique, t. iii., p. 3^; Fried 

 rich M'jflfman, HJnterlassene TT'erA-e. bd. ii.. s. 451-436. 



