DE VELOFAIENl OF SE IS MO LOG Y IN JAPAN 283 



that, while the other Pacific stations were showing depression, Abura- 

 tubo, i.e., the station nearest the origin of the recent earthq^uake 

 showed an npheaval in the few years prior to the earthquake. 



On the other hand, Imamura,^^^ from his studies on the distribu- 

 tion of lagoons on the coast of Kadusa, the investigation of some 

 erosion marks on the coast of Awa, as well as the examination of an 

 old document found infallible evidences of the remarkable vicissitudes 

 which the sea level must have suifered in ancient times. N. Yama- 

 saki^^^ studied the distribution of deposits and prehistoric remains 

 found in an erosion cave on the coast of Awa and succeeded in 

 tracing the sequence of terrestrial events back to the ages of our 

 remotest ancestors. 



Among the other phenomena accompanying earthquakes, changes 

 in some hot springs or artesian wells have often been reported,*^'' 

 especially in connection with the recent Kwanto^"*^ and Tazima^^^ 

 Earthquakes. In the former catastrophe, the geyser of Atami which 

 had been declining in activity for several years, was abruptly awaken- 

 ed into a contiauous eruption after the earthquake. In the case of 

 the Miyosi Earthquake^^^ of 1919, the wells situated on the north side 

 of a line passing through the epicentre decreased, while those on the 

 southern side of the same line increased in their out-put after the 

 earthquake. 



It was reported that at the Idusan spa^'^ the temperature of the 

 water was so abnormally high on the morning of the very day of the 

 great earthquake that bathing was impossible. 



Destructive sea waves or tsunami accompanying great earthquakes 

 of submarine origin have formed a subject for special investigations 

 by Japanese seismologists, since the terrible damage suffered in the 



(1) Ho., lOOB (1925). 



(2) Chikyd, 3 (1925), 74; Joum. Fac. Sci. Tok, [ii] 1 (1925). 



(3) E. Koto, Ho., 69 (1910). Imamura, Ho., 70 (1910). K. Aomi, Ho., 82 (1915). 

 Oraori, Ho., 88C (1920). I. Ikegami, J.M.S., 28 (1909), 307. G. Isida, J.M.S., 34 (1915), 

 61. T. Sasaki. J.M.S., 35 (1916), 147. K. Kondo, J.M.S. 37 (1918), 153. 



(4) In different papers on the great earthquakes already cited. 



(5) Among others Nakanmra, Saito HOonkwai G.K. llokoku, No. 1. 



(6) S. Nakamura and S. Aoki, J.M.S., 38 (1919), 395. 



(7) Saem. Nakanmra., Ho. lOOA (1925). 



