162 A. Imamura 



Japan but also far beyond it. Disasters cansed by them, however, 

 were experienced only at a few sea-side places bordering Sagami Bay, 

 as follows : — • 



Atanii (height 12 ra.), Ito (height 8 m.), Aziro (heights m.) and 

 Ainohama (height 9 in.) (PI. XV, XLIV.). In these places, the 

 flood washed away some houses and vessels and caught people and 

 cattle. The northern coast of Oosima, the southern coast of the Miura 

 Peninsula, and the coast between Kamakura and Enosima were also 

 visited by waves of the heights of about 8 m., 6 m. and 4 m. res- 

 pectively, but without much resultant loss. According to observations 

 made at Tateyama Meteorological Station, the water ebbed a few 

 minutes after the shock had been experienced as low as about 7 m. below 

 the former level, and after 5 min. flooded as high as 2 m. above the 

 former luark ; during the next 15 min., it ebbed again as low as 3 

 m., and 15 min. later it had flooded again as high as 1 m. ; after 

 this the waves became less and less, but were observable until 2 o'clock 

 in the afternoon. Here it must be remarked that the new level soon 

 after the first shock must be lower by 1.6 m. than the former one. 



The height of tunanii is not so great in an open sea ; it increases 

 as the waves gi-adually approach shallow water and enter into a 

 V-shaped port. According to Dr. Ikeda, the height of Pmaord at 

 Atami was only 1.5 m. at the two promcmtories, and 3 m. midway 

 l)etween the northern jiromontory and the corner of the port, while it 

 attained the enormous height of 12 m. at the corner. Similar 

 observations were made by him as to the tunami at Aziro and 

 Ainohama. 



One more interesting investigation by Dr. Ikeda was on the direc- 

 tion of wave propagation. In Atami, the tunami came in from ENE 

 and was principally reflected towards the opposite direction except its 

 southern part which was reflected towards ESE. In Aziro it was 

 propagated from NE and was reflected eastwards. In Ainohama it 

 came in from W and its northern part was reflected towards the 

 opposite direction, while its southern part was reflected towards S or 

 SW. Comparing these modes of wave propagation with the map of 

 submarine change, it will be found that wherever tunami came from, 

 there lies unmistakably an area of conspicuous elevation in the sea- 

 bottom nearby. Thus the present tunami seem to have been caused 

 for the most part liy the elevation of the sea-bottom, the enormous 

 depressions playing only a small part in p educing tunami which rose 



