DOMAIN xn. VOLCANIC. 307 



irregular, and pass into the amorphous 

 lava. At the Motta, already mentioned, 

 they are about two feet in diameter, partly 

 vertical partly inclined. At the bottom of 

 the colonade the peasants made an aper- 

 ture, where, on introducing the hand, heat 

 was perceived, and the hand srnelled of sul- 

 phur. Above are great masses of sand* 

 red drosses, and puzzolana ; and he infers 

 that the prisms are in the centre of the 

 volcanic mass. It may be said indeed, 

 that heat thus enclosed becomes inextin- 

 guishable ; and he mentions that, two years 

 ago, the lava of 166'9 being perforated at 

 Catania, flames issued ; and within these 

 eight years it yielded, after rain, smoke 

 and great heat. This lava is about two 

 hundred feet in depth, and two miles in 

 breadth, and had run about fifteen miles. 

 Other basaltic columns appear near Bronte, 

 on the west of Etna, which gave a title to 

 the glorious Nelson. They are in beau- 

 tiful hexagonal groups, which disappear in 

 the incumbent chalk or earthy limestone. 

 Some not only project from one centre, 



x 2 



