Exploration of West Valley 



to the rift whence had issued the flood of lava which 

 we had first seen. Much steam, sulphur dioxide, and 

 hydrochloric acid were still pouring from the rift, but the 

 lava had ceased to flow. On account of the suffocating 

 nature of the fumes, it was impossible to approach 

 sufficiently near to obtain any idea of the depth of 

 the chasm, nor could we ascertain whether it had 

 originally communicated with the crater itself or with 

 the main conduit at a lower level. 



At length, after a wearying climb through the soft 

 loose dust, we reached the lip of the crater. Two hundred 

 feet below us was a flat floor, of which we obtained a 

 view at intervals when the vapours were swept aside by 

 the wind. During one clear interval we were able to 

 see that the floor consisted of two parts a central one, 

 which was constantly heaving, and an outer ring, which 

 appeared more stable. 



While we were watching, the central part seemed to 

 swell up into a great bubble, which burst with a roar, 

 hurling fragments of the slaggy crust into the air and 

 exposing the surface of the molten lava below. For 

 some minutes the surface of the lava remained in vio- 

 lent ebullition, fiery jets being projected from its sur- 

 face to a height of 20 feet or more. It then gradually 

 subsided and became crusted over with a solid scum. 

 This, in its turn, confining the vapours, was once more 

 raised into a dome, to burst in its turn and be followed 

 by another. This was the stage made familiar to us 

 by the writings of Judd 1 and others with regard to the 

 crater on the island of Stromboli, in the Mediterranean, 



1 Volcanoes, What They Are and What They Teach, by John W. Judd, 

 F.R.S., 1893, pp. i^etseq. 



235 



