Geology 



the cone, and there made our arrangements for the 

 night. 



The explosions continued at intervals of about half 

 an hour, and the column of dust and steam was occasion- 

 ally illuminated by vivid flashes of lightning. After 

 sundown the whole countryside was illuminated by a dull 

 red glow, evidently the light from molten lava in the 

 crater reflected from the steam cloud, which itself glowed 

 red in the intervals between the explosions. Immedi- 

 ately after each explosion the light suddenly increased 

 in intensity and became almost white, though slightly 

 tinted with orange. This light then gradually subsided 

 to the former dull red glow until the moment of the next 

 explosion. At its brightest it was possible to read 

 ordinary print at our bivouac by the light from the 

 crater. 



Throughout the night the explosions continued with 

 remarkable regularity, with the exception that occasion- 

 ally three or four followed each other in rapid succession 

 after a period of repose somewhat longer than the 

 average. 



The ascent of the large cone presented little difficulty, 

 but here and there we had to traverse fields of lava which, 

 though weathered to a reddish soil in some places, in 

 others still retained its slaggy, cindery surface, and on 

 these progress was slow, as care was necessary in 

 placing the feet, if we did not wish to have our boots 

 cut to pieces and our feet lacerated. 



The condition of the lava-field showed that it was of 

 no very great age, and therefore that this cone also had 

 been active at a comparatively recent date. 



Other parts consisted of volcanic ash as the fine 



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