28 K. HONDA, T. TER ADA, Y. YOSHTDA, AND D. ISITANl. 



Here a continuous record by Kelvin's tide-gauge has been 

 taken since some ten years ago ; many valuable records con- 

 nected with sea waves and low pressures were obtained. Our 

 observation was made at the tide-gauge station ; the observed 

 periods are 6.8'"-8.9'", 14.2"^-15.1™ and 20.9™-22.8"; while the 

 calculation gave 8.9"\ The same periods were also found in 

 the case of several sea waves accompanied by earthquakes or 

 atmospiieric low pressure. 



(11) Shiogama and Hiragata. 



From the records obtained by Dr. Imamura at Shiogama 

 in Eikuzen, and Hiragata in Hitachi, we found the following 

 periods : — 



44"' at Shiogama, 



28™ and 50™ at Hiragata. 



(12) Cape of Inuboye (Aug. 6-17, 1903). PI XII, Fig. 3. 

 The observation was made at tlie Cape of Inuboye. The 



secondary undulation was not conspicuous, being superposed 

 by the short waves of considerable amplitude ; the observed 

 undulations were 8.9'", 1(3.3™-I8.r", 20.0"\ 26.0"-29.8™, 31.0"- 

 34.4"\ 38.7™, 49.0™ and 66.0™. 



(13) Tokyo. Top. 29. PI. XIII, Fig. 1-4. 



On the coast of the Bay of Tokyo, several tide-gauges of 

 Kelvin's type are constantly w^orking. Our tide-gauge was set 

 up at Etchiujima and records were continuously taken from 

 Nov. 24 to Dec. 5, 1904. Since August, 1906, a tide-gauge 

 of our system has been placed at Kanegafuchi on the bank 

 of the River Sumida about 2 km. distant from its mouth. In 

 usual w^eathers, the undulation of the bay is very faint, but 

 regular and characteristic undulations of 63.1"'- 67.0™ and 

 72.0™-82.r" are sometimes observed. In addition, the long periods 



