18 K. HONDA. T. TEKADA, Y. YOSHmA, AND D. ISITANI. 



The observed periods are 13.8'"-16.5'", 24.3"\ 3G.1™, 45.0"^; 

 in the above and in what follows, the lieavily printed figures 

 denote the conspicuous undulation. The calculated period 

 17.3"' fairy coincides with the observed period of the conspicuous 

 undulation. 



It should be remarked that in our observation, short waves 

 of periods not exceeding a few minutes were always eliminated 

 by properly adjusting the tide-gauge. 



(2) Nemuro (July 28-31, 1905). Top. 2. PI. I, Fig. 2. 



Nemuro is a small bay on the eastern extremity of Hok- 

 kaido ; here the tidal range is tolerably large. Tlie periods 

 observed are 10.9", 33.7™, and 38.6"; while the calculated 

 period is 9.0"". 



(3) Hanasaki (July 31-x\ug. 1, 1905). Top. 3. PI. I, Fig. 3. 

 Hanasaki is a shallow inlet on the Pacific coast not far 



from Nemuro ; here also Kelvin's tide-gauge is constantly work- 

 ing. The undulation is generally inconspicuous, but regular 

 undulation of long period may often be traced : The periods 

 observed are, 6.9'", 14.2'"-17.7"\ 19.2'"-23.2'", 38.8", 44.5" and 

 61.2"'-65.6"; the calculated period is 10.9". 



(4) Hamanaka (Aug. 4-5, 1905). Top. 5. PI. H, Fig. 1. 

 Hamanaka is a bay situated on the south-eastern coast of 



Hokkaido. The observation was made at Kiritapp on the west- 

 ern side of the bay. During the observation, a low atmospheric 

 pressure was approaching from the Pacific side of Honshiu to 

 Hokkaido, and a conspicuous, but not regular undulation of 

 long period appeared on the record. Periods observed are 20.9'", 

 24.2", 49.5", 62.3"' and 84.3"', while the calculated is 48.2"'. 



(5) Mororan (Aug. 17-22, 1905) Top. 7. PI. II, Fig. 2-3. 

 Mororan is a small bav on the southern side of the Volcano 



