INTRODUCTION. 



the other. Such is the mountainous mass, terminating' in 

 the summit, upon which stands the village of Carlentini. 

 To suppose, with Dolomieu, that the lava pressed through 

 the vale, whence, rising by the side, it arrived at the top, 

 without having passed to the other side, is to suppose an 

 order of things which can never have existed at the epoch 

 when the lava was fluid. In fact, this division does not exist 

 when you proceed towards the west, above Lentini, where 

 the lavas cover all parts, that is, the volcanic stratum covers 

 all that extent. The same phenomena are observable in the 

 mountains of Canzaria, near Vizzini, and in some which are 

 in the plain of Marineo, beyond Licodia. In all these strati- 

 form mountains the position of the strata of similar materials 

 corresponds from one mountain to another ; a circumstance 

 which may be estimated by the eye, where the breadth of the 

 valleys is not too great* This circumstance demonstrates the 

 character of the revolutions which have produced these in- 

 equalities." * He afterwards proceeds to state the sinking of 

 a part of a mountain in 1536, and the catastrophe which 

 happened at Nicosia about 1750, when a fourth part of the 

 city, with the convent and churches of the Capuchins, sunk 

 in one day, so that nothing could be seen but the tops of 

 the buildings, and of the trees j but the people escaped by 

 stepping out of the windows. In 1740 the town of Salemi 

 suffered the same misfortune j and in 1790 some lands sunk 

 near S. Maria di Niscemi. He also states that the people of 

 a place, a few miles to the west of Catania, thirteen years ago 

 could only see the top of the cupola of the Benedictine mo- 

 nastery of that city, the prospect having been impeded by 

 the lava of 1669, but now the entire cupola is seen, the 

 chalky soil under the lava having subsided f. 



Perhaps this doctrine of subsidence might of itself explain 

 the inequalities and other phenomena of the earth's suiface, 

 without having recourse to any concussion of a satellite or 

 other body. The summits of basalt, and the caps of lime- 



* Ferr. 376. f Ferr. 378. 



