374 CALORIFICATION. 



these fountains of fire from the exactness in the 

 line of their direction, proceeded from one and 

 the same long fissure, one mile and a half in 

 length down the flakes of the mountain, and 

 that the lava and other volcanic matter, forced 

 its way out of the widest parts of the crack 

 from many mountains and craters. This fiery 

 scene was accompanied by the most horrid 

 noise; it was as the mixture of the loudest 

 thunder with incessant report like that from a 

 numerous heavy cartillery, accompanied by a 

 continual hollow murmur like that of the roar- 

 ing of the ocean during a most violent storm. 

 And added to this was another blazing noise 

 like that of the going up of a large flight of sky 

 rockets, similar to that which is produced by 

 the enormous bellows of the furnace of the 

 iron Carron foundry in Scotland. All that 

 time, there was not the smallest appearance of 

 fire or of smoke from the crater on mount Ve- 

 suvius. But the black smoke and ashes issu- 

 ing continually from so many new mouths and 

 craters, formed an enormous and dense body 

 of clouds over the whole mountain, replete with 

 the electric fluid, making flashes of a zig-zag 

 form, called here Ferilli. Out of these gigan- 

 tic and volcanic clouds, I have seen balls of fire 

 issue and burst in the air: on the 16th, the 

 crater of Vesuvius showed signs of being on fire, 

 by some black smoke issuing out of it. At day- 



