30 K. HOKDA, T. TEßADA, Y. YOSHIDA, AND D. ISITANI. 



different parts of the bay showed the identity of waves with 

 respect to their forms and phases. PI XIV, Fig. 2 and PL XV, Fig. 

 1 , or PL XIV, Fig. 4 and PI. XV, Fig. 2 are the records of the simul- 

 taneous observations at Moroiso and Abm-atsubo. PL XIV, Fig. 

 5 and PL XV, Fig. 3 are the records of the simultaneous ob- 

 servations inside and outside the bay; placing the one record 

 upon the other, we can distinctly trace undulations in the two 

 records, which correspond to each other. The amplitude of the 

 wave outside the bay is however very small, as compared with 

 that of the undulation inside the bay. PL XV, Fig. 4 is a 

 record at Aburatsubo in a stormy weather. 



(15) Atami (April 2-7, 1905). Top. 31. PL XVI, Fig. 1-3. 

 Atami is a town situated on the western side of the Bay 



of Sagami and famous for the geyser Ji The secondary undula- 

 tions were so inconspicuous as to make it difficult to detect 

 their periods. We can, however, sometimes trace on the records 

 the periods 12.8'", 72.4"'-7C).2" and 97.G'". 



(16) Shimoda (Jan. 4-8, 1906). Top. 32. PL XVII, Fig. 1-3. 

 Shimoda is a small liarbour at the southern end of Izu 



peninsula. The amplitude of the secondary undulation is so 

 conspicuous that it is generally known as ijota. The oscil- 

 lation becomes conspicuous, when a centre of low pressure is 

 approaching from the Pacific towards the place. The periods 

 observed are 11.9™, 13.8"-18.2™, 21.5"' and 30.9'". 



In the bay, two extreme nodal lines are conceivable, the 

 periods corresponding to these lines are calculated to be 13.3'" 

 and 15.9'". Hence any wave of the period lying between the 

 values 13.3"' and 15.9'" may excite the osciUation of the bay; 

 the periods actually observed fall nearly witliin the same 

 limits. 



