THE COASTS OF SICILY. 119 



rior of that partial sinking, which we have referred 

 to as la Citerna* 



There was therefore an epoch in which the primi- 

 tive nucleus of Etna rose solitary in the midst of the 

 plain, towering above the whole island of Sicily with 

 its abrupt and irregular outlines, but this condition of 

 things was necessarily soon subjected to various modi- 

 fications. Dating from the present geological epoch, 

 the eruptions which have occurred upon its sides and 

 round the central elevation have levelled the base of 

 the mountain, and given rise to lateral slopes whose 

 declivities and general aspect plainly reveal their 

 origin. These lava beds, ashes, and scoria?, were a 

 sort of modern vesture, beneath which the volcano 

 concealed its primitive form and veiled its origin. 

 The winds, rain, and streams, have carried into the 

 plain an enormous mass of these moveable substances, 

 and thus gradually formed at different points slight 

 elevations of the soil. We thus see that these se- 

 condary causes have incessantly tended to raise the 

 base, and to level the plains ; and it is to the same 



* One is naturally led to ask at what epoch those phenomena 

 can have occurred, of which we have endeavoured to give some idea 

 in the preceding remarks. M. de Beaumont regards the upheaval 

 of Etna, as having immediately preceded our present geological 

 epoch. He believes that the outpouring of the ancient lava of the 

 Val del Bove is contemporaneous with the formation of the chains of 

 Atlas, the whole of which form a line bordered to the west by the 

 Canaries and the Peak of Teneriffe, and to the east by Sicily and 

 Etna. These determinations result from the general theory of up- 

 heavals and from the consequences which M. if lie de Beaumont has 

 deduced from them as to the relative age of mountain chains. (See 

 M. de Beaumont's work on Etna, and his article Soulcvements in the 

 Dictionnaire Universelle d' Histoire Naturelle.) 



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