SECOND AKY UNDULATIONS OF OCEANIC TIDES. 31 



(17) Shizuura (Sept. 4-6, 1904). Top. 36. PI. XVIII, Fig. 1. 

 In Shizuura near the end of the Bay of Suruga, the 



secondary undulation is not conspicuous. The periods observed 

 are 18.r-19.6" and 71.0'". The calculated value is 54.5™, so 

 that the conspicuous undulation may be a binodal oscillation of 

 the bay, but the amplitude of the wave being very small, the 

 wave is possibly a progressive one. 



(18) Omaezaki (July 31-Aug. 5, 1903). PI. XVIII, Fig. 2. 

 The station is situated on a south-eastern corner of Tôtômi ; 



the undulation is very inconspicuous. The periods observed are 

 IS. 6'" and 27.7"\ 



(19) Maisaka (July 17-28, 1903). PL XVIII, Fig. 3. 

 Maisaka is situated on an open coast of the same province. 



The undulation is inconspicuous ; the observed periods are 

 10.0'", 16.0^ 20.2"'-23.4™, 30.2'" and 55.0™. 



(20) Kamagôri (Sept. 1-3, 1904). Top. 38. PI. XIX, Fig. 1. 

 Kamagori is situated near the eastern end of the Bay of 



Mikawa ; this bay has a considerable area, and is very shallow, 

 so that its oscillation can not be easily excited by any ordinary 

 cause. The undulation is not very conspicuous, observed periods 

 are 18.7", 36.5'^^ and 43.2^-45.1'". An undulation of long period 

 of 208'" may also be traced. 



(21) Kamezaki (Aug. 31-Sept. 2, 1904). Top. 38. PI. XIX, 

 Fig. 2. 



Kamezaki is situated near the northern end of the same 

 bay. Inconspicuous undulations of 44.5'" and 68.0'" are observed ; 

 a period of 390™ may also be traced. 



During our observation, we met with a storm, but the am- 

 plitudes of the slow undulation were not much affected by it. 



The Bay of Mikawa and the Sea of Ise form a large con- 



