Geology 



and which also occurs in certain stages of some eruptions 

 of Vesuvius. 



The activity was still too violent and the quantity of 

 vapour too great to allow of a descent into the crater 

 being attempted, though we were able to locate a track, 

 by which, under more favourable circumstances, there 

 would be but little difficulty in reaching the crater floor, 

 and we hoped that, on a subsequent visit, we should be 

 able to accomplish this descent and make an examination 

 of the inner walls of the crater and of the central pit. 



236 



