( 235 ) 



%7]ilch are very hard, the labourers have 

 recourfe to the following dangerous method. 

 A man, faftened by a rope, is let down to 

 a certain depth againft the perpendicular 

 fides of the cavern ; and, the other end of 

 the rope being made faft at the top, breaks 

 the flone in pieces with pickaxes, availing 

 himfelf of certain vertical fiilures, which 

 greatly facilitate the labour. Mines are 

 like wife prepared, in fome cafes, which 

 blow the fragments of the ftone into the 

 air. 



In this excavation, and in another of 

 lefs dimenfions, not far dlilant, the lava of 

 the mountain is truly granitous, and the 

 granite has for its bafe the feltfpar, which 

 is fo abundant that it compcfes the greater 

 part of the rock. It would be fuperfiuous 

 to dcfcribe it, as it is perfectly funilar, even 

 in its cryftallization, to that of Monte Rcflb 

 and Monte Ortone. Befides the feltfpars, 

 which, by their brilliancy and other exclu- 

 five chara(£«:ers, immediately declare their 

 mature, certain white fpots prefent them- 



felves 



