THE ERUPTION OF BAXDAI-SAX. 109 



In describing the phenomena of the earth and rock debris, the 

 word mud has been frequently used by several observers, who 

 speak of 'mud-stream,' 'mud-field' etc. \Ye also have used the term 

 above, but it must be explained, to avoid misconception, that we have 

 done so for convenience only. Some commentators, indeed, have er- 

 roneously classed the phenomena with those of the 'mud volcanoes' 

 of which we read in geological text-books that, while some have 

 been known to throw up mud to a great height, in others liquid 

 earth only oozes out quietly, and gradually forms an earth-ring round 

 the crater. Such outbursts, however, are no more than moderate 

 manifestations of subterranean energy, and are almost insignificant 

 in comparison with the tremendous forces that destroyed Kobandai- 

 san. Moreover, as far as our prolonged examinations went, there was 

 no evidence of any discharge of mud from beneath. It is true that 

 in the Nagase valley and other places there are now immense quan- 

 tities of mud, but these became mud only after the eruption. During 

 its descent, for example, a part of the débris, mingling with the waters 

 of ponds and lakes in its course, doubtless acquired a muddy cha- 

 racter and was thus assisted in its flow; and, again, that which reach- 

 ed the stream of the ^aii'ase-o'awa became admixed with sufficient 

 water to thin it to the consistency of a paste. But by far the greater 

 volume was comparatively in a dry state, being moistened only by 

 condensing steam, and must have derived its fluid or semi-fluid pro- 

 perties from a rapid process of pulverization after the manner already 

 described. 



With regard to the secondary mud-stream that ran down to 

 Miné, there has been a diversity of opinion. Some visitors imagined 

 that there must have been more than one crater — that, in fact, the 

 materials which destroyed Miné had a separate origin from the rest; 

 and a cleft or depression at Hikage in Biwasawa, which, as viewed 



