tfOME IV. TUFO. 397 



heavy lava, of which the whole of this current 

 seemed to be composed. 



" Learning for certain that there was not on 

 the north of Etna any new current of lava, I trod 

 back my steps towards Nicolosi. I re-ascended 

 the mountain on the llth of August, and bent 

 my way directly towards the crater, to examine 

 the changes which an explosion so violent must 

 necessarily have effected : smoke rose from the 

 crater in great abundance, and to a considerable 

 height; but, driven by the wind towards the 

 east, it was no prevention to my plan. 



" From the very walls of Nicolosi I noticed 

 that the earth was covered with small fragments 

 of light dross, which became larger in propor- 

 tion as I approached the summit ; I found they 

 had covered the whole space denominated the 

 plain del Lago y in such manner that the former 

 soil could no longer be distinguished; the time 

 of my departure on the excursion was half past 

 nine in the morning, and the thermometer stood 

 11^ (52\ of Fahrenheit). 



and it disappeared at three feet distance from the lava. To ascertain 

 correctly whether or not there really was any difference in the state 

 of electricity, I several times got upon and descended from the lava, 

 and found not the slightest divergency of the balls on removing to a 

 distance of forty paces j the slight electricity in the lava was of a posi- 

 tive kind, as I convinced myself by means of a stick of Spanish wax." 



