THE COASTS OF SICILY. 117 



We may now form to ourselves a tolerably exact 

 idea of the successive phenomena to which Etna 

 owes its present shape and proportions. The spot on 

 which the central elevation now rises was originally a 

 nearly horizontal plain, whose soil, broken up by the 

 action of subterranean fires, has at different epochs 

 given passage to currents of very fluid lava. This 

 lava has spread into thin and uniform sheets around 

 these blow-holes, and in solidifying, they have 

 formed ledges of rocks, whose compactness depended 

 upon the thickness of the streams. As in the case 

 of eruptions at the present day, the ejection of these 

 fused substances was accompanied by a violent libe- 

 ration of elastic fluids, which carried with them 

 large quantities of cinders, scorise and lapilli. 

 These substances, which were extremely solid, issued 

 from all the fissures, and falling back in a shower 

 upon the bath of lava, have thus produced these 

 uniform strata of stony and scoriaceous fragments 

 which alternate with those composed of rocks. 



These phenomena very probably continued to 

 occur for many ages, but at length a moment arrived 

 when the internal forces, which had so many times 

 burst their way through the soil, displayed some ex- 

 traordinary degree of energy, perhaps on account of 

 the ever increasing resistance which was opposed to 



further particulars to the original memoir of M. Elie de Beaumont. 

 The maps and drawings which accompany the text will remove all 

 doubts, and we more especially recommend to them the study of the 

 plan, which was modelled by that geologist, and of which a copy is 

 exhibited in the Jardin des Plantes. 

 I 3 



