THE ERUPTION OF RANDAI-SAX, 93 



inonly culled smoke) rising up in the air? Its colour, height, form, 

 etc. Did they see lightning in the steam, or lire on the volcano? 

 How did the lightning or fire look? Did volcanic dust fall? Its 

 thickness, colour, consistency, structure, etc. Were there any earth- 

 quakes either before or after the eruption? Their times of occurrence, 

 intensity, duration, nature, etc. The state of lakes, rivers, and springs 

 before and after the explosion. The meteorological conditions, es- 

 pecially the force and direction of the wind. Any other information 

 bearing on, or which might seem to bear on, the eruption was also 

 asked for. The answers to these question- are given in a tabular 

 form at the end of this paper. 



Bandai-san, considered topographically and geologically. 



In Northern Japan, there run along the Pacific seaboard two 

 principal masses of mountains, chiefly composed of crystalline and 

 older rocks. The more northerly of the two. on the eastern side of 

 the Kitakami River, has been named by Dr. E. Naumann the Kita- 

 kami Mountain-land, and the other, situated to the east of the Abu- 

 kuma River, the Abukuma Mountain-land. These two mountain- 

 masses are remarkably similar in their geological structure, and the 

 principal direction of strike is north and south. Thev are very old 

 formations, consisting of granite, granite-gneiss, gneiss, and other 

 crystalline schists, together with thick accumulations of Pakeozoic 

 strata, much folded and faulted, and some patches of Mesozoic strata 

 not less disturbed. We have, in fact, the relics of old land, the 

 principal features of which must have been determined at the end 

 of the Mesozoic Era, and much of which has, no doubt, been sub- 

 sequently denuded away. 



On their western sides, the two mountain-lands face broad val- 

 leys, in which the rivers already mentioned run in a meridional 



