33 C 2 DOMAIN XII. VOLCANIC. 



sequence the dust produced by pulverising them, 

 < copiously adheres to the point of the magnetised 

 knife ; and a small piece of these scoriae will 

 put the magnetic needle in motion at the dis- 

 tance of two lines. 



Bails of lava. In the midst of this immense quantity of 

 scoriae, I in several places met with some sub- 

 stances of a spherical figure, which, like the 

 lava, were at first small, but increased in size as 

 I approached the summit of the mountain. 

 These were originally particles of lava ejected 

 from the crater in the eruption before mention- 

 ed, which assumed a spherical figure when they 

 were congealed by the coldness of the air. On 

 examining them, I found them in their qualities 

 perfectly to resemble the scoriae, and to possess 

 the same magnetism. 



Smoke. t( Only two miles and a half remained of our 



journey, when the great laboratory of nature, 

 enclosed within the abysses of Etna, began its 

 .astonishing operations. Two white columns of 

 smoke arose from its summit : one, which was 

 the smallest, towards the north-east side of the 

 mountain ; and the other towards the north-west. 

 A light wind blowing from the east, they both 

 made a curve towards the west, gradually di- 

 lating, until they disappeared in the wide ex- 

 panse of air. Several streams of smoke, which 



