202 M. Arago on the [March, 



Eyafialla-Jokul ; Iceland, south-east of Hecla. 



Eyrefa-Jokul ; ditto. 



Skaptaa-Jokul ; ditto. 



Skaptaa-Syssel ; ditto. 



Wester-Jokul ; ditto. 



Esk ; island of Jean Mayen. 



Vesuvius, the only volcano now in activity upon the conti- 

 nent of Europe, has been repeatedly extinguished, and in com- 

 bustion. Before the reign of Titus, this mountain was much 

 visited, and is mentioned only on account of its extraordinary 

 fertility. Vitruvius and Diodorus Siculus, who lived in the time 

 of Augustus, do indeed state, upon historical authority, that 

 Vesuvius had formerly vomited fire like Etna ; but these state- 

 ments refer to remote and nearly forgotten periods. 



It was on the 24 th of August in the 79th year of the Christian 

 era, that Vesuvius was rekindled. This eruption buried the 

 cities of Herculaneum, Pompeii, and Stabiaea ; and it will be 

 recollected that Pliny, the naturalist, perished, as the victim of 

 the ardent curiosity with which he was inspired by this interest- 

 ing phsenomenon. 



After the eruption of the year 79, the volcano remained in 

 combustion for 1000 years ; still later it appeared to be totally 

 extinct; so that in 1611, the mountain was inhabited almost to 

 the summit, and there were a copse and small lakes in the inte- 

 rior of the crater. 



Etna. — Pindar, who lived in the year 449 before the Christian 

 era, mentions Etna as being in a state of combustion. Thucy- 

 dides has preserved some details of the eruption which occurred 

 476 years before Christ. As to Homer, he does not even men- 

 tion the mountain, although in the Odvssey he disembarks 

 Ulysses in Sicily. The silence of a poet who has always been 

 admired for the extent and universality of his knowledge, has led 

 to the probable supposition, that long before the time of Homer 

 the volcano was extinct. The Roman historians, both of the 

 middle ages and of modern times, have described so great a 

 number of eruptions of Etna, that it probably would not be diffi- 

 cult to prove that during a period of 2000 years it was never 

 extinct for a whole century. 



Seneca has observed that volcanic mountains do not supply 

 the combustible matter of the fire, but that they merely give it 

 vent. Father Kircher seems to have commented on these words 

 of the Roman philosopher, when in the fourth book of his Sub- 

 terranean World, he has advanced the opinion that the matter 

 ejected from Etna, would, if formed into one mass, form a moun- 

 tain 20 times larger than Etna itself. The work of Father 

 Kircher appeared in 1660. Nine years afterwards a single 

 eruption of the volcano, covered with lava a space of six leagues 

 long, two and a half in width, and of a mean depth of at least 



