( I02 ) 



caverns incomparably deeper produced by a 

 fimilar caufe. 



Immediately beyond the Grotta del Bove 

 Marino, we meet with a mixture of tufa 

 and lava, which merits fome attention from 

 the curious alternation of its ftrata. They 

 are found on a high precpice which defcends 

 into the Tea, the fur-ace of which is covered 

 with a tufaceous foil, refting on a bed of 

 lava, above another of tufa, and fo fuc- 

 ceflively, that in a rent made in the pre^ 

 cipice by the waters we may number eleven 

 ftrata or beds of tufa, and as many of inter* 

 pofed lava. It appears, therefore, that the 

 fire and water, by their repeated adlion, 

 have produced this mixture of lavas and 

 tufas. 



The lava of^ the eleven beds is of the 

 fame kind, that is, of a horn-ftone bafe, and 

 containing, as ufual, (hoerls and feltfpars. 

 It has an earthy afped, a blackifh colour, 

 and a ftrong argillaceous odour. It moves 

 the magnetic needle at the diftance of two 



lines, 



