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have exceeded one hundred and fifty or two 

 hundred toises ; even taking into the account 

 the depth of the sea, the bottom of which had 

 been lifted up : but when we are considering 

 the great effects of nature, and the intensity of 

 it's forces, it is not the bulk of the masses, that 

 ought to stop the geologist in his speculations. 

 Every thing indicates, that the physical changes 

 of which tradition has preserved the remem- 

 brance, exhibit but a feeble image of those gi- 

 gantic catastrophes, which have given mountains 

 their present form, changed the positions of the 

 rocky strata, and buried seashells on the summit 

 of the higher Alps. It was undoubtedly in those 

 • remote times, which preceded the existence of 

 the human race, that the raised crust of the 

 Globe produced those domes of trappean por- 

 phyry, those hills of isolated basalt on vast ele- 

 vated plains, those solid nuclei which are clothed 

 in the modern lavas of the Peak, of Etna, and 

 of Cotapaxi. The volcanic revolutions have 

 succeeded each other after long intervals, and at 

 very different periods ; of this we see the ves- 

 tiges in the transition mountains, in the second- 

 ary strata, and in those of alluvion. Volcanoes 

 of earlier date than the sandstone and calcareous 

 rocks have been for ages extinguished ; those 

 which are yet in activity are in general sur- 

 rounded only with breccias and modern tufas ; 

 but nothing hinders us from admitting, that the 



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