ERUPTION OF STROMBOLI PEERET. 289 



3. The ash emission of the 1912 eruption was accompanied by 

 strong electrical manifestations, the volcanic lightnings being vivid 

 and almost incessant. 



4. The products of the fumaroles of tliis eruption, collected by the 

 writer and analyzed by Dr. Ilenze, of the Naples Aquarium, consist 

 principally of Al, Fe, and Mg, combined with II2SO4 and HCl. Their 

 gaseous emanation, as tested on the spot, was cliiefly SO^ and a 

 trace of H2S. 



5. The eruptive months are six in number and have been desig- 

 nated by the writer with the letters A^o F, inclusive. 



6. The eruption proper lasted from July 22 to August 14, 1912. 



7. The crater of 1907 was 200 meters in diameter, very deep, and 

 the throat of the volcano was left quite free, permitting the gases to 

 escape cjuite continuously after the eruption. 



8. The eruption of 1912 enlarged the former crater to 300 meters 

 and left it partly filled Avith collapsed cone material. Tliis tends to 

 confine the gases until they break through at intervals and form an 

 ash cloud, giving the impression of a greater activity than really exists. 



9. The paroxysmal gases, as at Vesuvius in 1906, had approxi- 

 mately the composition of atmospheric air. 



