412

LIFE OF COLONEL;MACERONI.

of : Misenum , M rhave .'forgotten; to ^mention, that during.the .celebrated; eruption '.of, 'the 'Volcano , to ; which theIsland of Ischiaows its original formation, ,and which tookplace in the year 1102,-a,huge,dense volcanic'cloud, detach-ing itself;from the mountain of;Ischia, .;slowly approachedthe .point;of Misenum ',;which rises, like the Table Mount.Whether it was so driven by the .wind,, or attracted,by someinfluence of ai negative; state- of electricity, at that instant,peculiar to*.the:devoted spot, I- cannot; tell, but I am dis-posed to think the latter.-: The cloud 'of. ashes, smoke, andvapour, approached; the . town; discharging : all the. whilenumerous zigzags of electricity; but;when within the. properattractive., distance it/discharged'.teni millions'.of electricglobes to ;the attracting height,- and, as.though'it.had beena shower of bombs, levelled , the habitations to the earth.This eruption', of Ischia .of 1102.' must have been of. pro-digious magnitude.and violence. , A stream of lava whichon that, occasion- proceeded; from the' crater into the sea isabove;a mile' iii: breadth,;in many places eighty.feet thick,and it still retains, its .heat, iso; that upon a fall.of snow Ihave, seen the whole island whitened, save that track of lavawhereon if- had immediately, melted.. That streams of lavashould retain .their.heat for so many centuries will not appearto us so incredible when:we reflect upon the enormity.of themass, and ,the cellular nature of the Supper crust and scoria:,of aluminous earths, which are very bad conductors of heat. •The volcano of Ischia may be .called extinct, as all otherswill one day become,', so soon:as this .our .earth shall bearrived at that period of its existence corresponding to themature age of animals. ;At that period' the expansive agita-tions of its interior will "be overcome by’the external com-pressive forces. Senility .’will then follow; and the pro-ductions and fertility of the surface, being no longeralimented by the eleetrico-galvanico-magnetic emanations