94 Messrs. K. Honda, T. Terada, and D. Isitani o?i the 
recorded several important sea-waves which had their origin 
near the American coasts of the Pacific, as well as near our 
coasts. 
Fiar.l 
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At Hakodate the secondary undulations are very promi- 
nent, sometimes exceeding 30 cms. in amplitude, and of 
fairly regular periods. The periods* of the most conspicuous 
range from 45 m '5-57 m, 5. Sometimes its octave 21 m '9-24 m *5 
is found superposed on the undulation of the above period. 
In the undulation accompanying the sea-waves the octave 
generally appears in a marked degree. 
When observations at Hakodate and Kamiiso were carried 
on simultaneously, it was found that only the fundamental 
oscillation appeared on the records. The comparison of our 
records showed that the phase of the undulations was the 
same for these two stations. When like observations were 
made simultaneously at Hakodate and Tachimachizaki, it 
was noticed that although the conspicuous undulation appeared 
in the bay, yet just outside it was very insignificant. These 
observations agree well with our view regarding the secondary 
undulations, which we have propounded in the foregoing- 
Section. 
If we consider the longer period to correspond to the 
fundamental oscillation, and the shorter period to the lateral 
oscillation of the bay, the calculated periods for these oscilla- 
tions are respectively 45 m, 3 and 23 m, 6, which coincide well 
with the observed values. As we shall see hereafter, the 
periods corresponding to these two modes of oscillation, as 
given by our model of the bay, are also 47 m *0 and 23 m *6. 
* Figures in heavy type always represent conspicuous undulations. 
