99^ M, L. Elie de Beaiimount on the Structure and 



sarily corresponded principally with the line of soulevement, or 

 diverged in a radiating manner at its extremities, — a feature 

 which the memoir shews is in accordance with the phenomena as 

 they actually occur. 



The elliptical amphitheatre of the ValdelBove presents, then, 

 all the characters of an irregular crater of soulevement ; but 

 here, as in all analogous cases, the question presents itself, as to 

 what has become of the matter which formerly filled up the 

 now empty space of the circus, and whose extent the fractures 

 produced by the soulevement could not nearly have equalled. 

 I have already discussed this subsidiary question, and with- 

 out pretending to decide in an absolute manner, I have an- 

 nounced that I coincide with the opinion expressed by Dr Buck- 

 land, Mr Lyell, and M. de Buch, who regard as the most pro- 

 bable hypothesis that which maintains the swallowing up of the 

 massinthe interior abysses of the mountain ; a view which seems 

 to me so much the more probable, that it is in some measure in- 

 dicated by the phenomena on a smaller scale, but still of an ana- 

 logous nature, which occurred on the surface of the Piano del 

 Lago, under our own observation in 1832, and at other recent 

 epochs. 



It remains to be ascertained whether this soulevement was 

 gradual, or was effected suddenly and at once. The latter sup- 

 position seems to me the only one that is admissible. In fact, 

 the nearly perfect resemblance which exists between the volcanic 

 matters composing the nucleus of the central gibbosity, and those 

 which are produced by Etna at the present day, leads us to the 

 belief that the volcanic fire acting at the present time, is only 

 the continuation of that which produced the ancient ejected sub- 

 stances. Now, the fire not being extinct, if the soulevement had 

 been gradual there would have been a continuity and entangle- 

 ment of the ancient and modern products ; there would not have 

 been that complete discordance of position between them, which 

 constitutes one of the most striking features of the structure of 

 Etna. 



Such is, in substance, the result of the observations with which 

 I have been occupied on the flanks of this volcano; nevertheless, 

 I might have believed that my essay was incomplete, if I had 

 terminated without discussinc:, as connected with the facts of the 



