Notice of Active and Extinct Volcanos. 279 



The existence of submarine lavas proves the action to have com- 

 menced before the retreat of the ocean, notwithstanding- which 

 eruptions occur here more frequently at present than they do at 

 Vesuvius or in any other known case. 



" Besides Hecla, which has been twenty-two times in a state 

 of activity during - the last eight hundred years, five other volca- 

 nos are enumerated, from which the total number of recorded 

 eruptions during the same period is no less than twenty. Some 

 of these happened at the same time at which the volcanos of 

 the Mediterranean were in action, but the instances of this coin- 

 cidence are not sufficiently numerous to lead to any certain con- 

 clusion. ' 



"In the year 1783 a submarine eruption took place six or 

 eight miles from Reykiavess, which gave birth to a new island a 

 mile in circumference, which however the following year again 

 disappeared. A submarine eruption also took place about the 

 same time seventy miles from the same cape, which is said to 

 have thrown up pumice sufficient to cover the sea for a space of 

 one hundred and fifty miles round." 



Greenland. 



In the island of Mayen, off the coast of Greenland, there is 

 a volcano whose crater is five hundred feet deep, and two 

 thousand in diameter. In 1 807, Captain Scoresby saw marks 

 of a recent eruption ; cellular lava, tufa, scoriae, &c. 



Grecian Archipelago. 



Our limits will not permit us to follow Professor Daubeny 

 through the historical research connected with the volcanic 

 history of the Grecian Archipelago, and we must be in general 

 satisfied with conclusions only. 



The island Santorino or Thera, and the smaller neighbor- 

 ing one Therasia are stated by Pliny, to have been thrown up 

 by the sea, and they are composed almost entirely of volca- 

 nic substances. There is also, Canimeni or Micronesi, 

 thrown up in 1573 ; and new or black island in 1707. The 

 following facts are too interesting to admit of abridgment, 

 and therefore we quote them entire. 



" Thevenot mentions a great eruption of pumice as having ta- 

 ken place in the sea near Santorino in 1638, and Father Goree 

 in 1707 was eye witness of the appearance of a new rock be- 

 tween little and great Cammeni, which increased in size so rap- 

 idly, that in less than a month it became half a mile in circum- 



