164 



A. Imamuea 



be enumerated as follows : namely, the lowering of the water level 

 in wells, the abnorn}al eruption of geysers, the crossing of a low 

 barometric i)ressure along Hoknrokudo towards Kinkwasan in N. E. 

 Japan and consequently the development of a secondary low ]:)re?sure 

 in the northern part of the seismic area, etc. 



It must also be remarked that there were some evidences of 

 tlie existence of the fundamental cause before the occurrence of 

 catastrophe. One is the recent active state ot the dependent seismic 

 zone in Japan, and the other is the gradual upheaval of the seismic 

 area. 



In connection with the first, let us enumerate the large earth- 

 quakes which have taken place in the same zone during the last few 

 years. They are shown in Table IV. 



Table IV. 

 Eecont large earthquakes ia N. Pacific t^^eismic Zone. 



