54 ' s. Nakamuro, and K. Honda : 



formula of Du Boys in its mode of calculation, and ought to give 

 the best value. It seems somewhat remarkable that the calculated 

 value 1G.2 is the only value that exceeds the observed value 

 noticeably, other modes of calculation giving generally too small 

 values. 



If we adopt Du Boys's formula, the positions of the nodes may 

 be determined by the following simple consideration. If the node 

 of the uninodal seiche is situated at .r=/, it is evident that it must 

 satisfy the condition that 



dx I dx 



r dx I 



V h 



Using the data given in Table 27, we find that the node of the 

 uninodal seiche is situated at 0.48 of the whole length of the lake 

 measured from the southern, Hakoné end. This is not in close 

 agreement with the result obtained in the experiment with the 

 model. The positions of the nodes for other motions may be 

 obtained in a similar way. 



In a paper entitled "Notes on seiches", Mr. T. Terada,* 

 comparing seiches with the motion of the air column in an organ 

 pipe, has calculated the correction to be applied to the length / {L 

 in our notation) of a lake, when the breadth B (our 6) and the area 

 iî of the transversal section are not constant; he has also calculated 

 the correction due to the lateral motion of the water; and has 

 shown that 



., 1 / 2-x / JB , JS \^ ,1 //. 2kx \f dB V , 



where the breadth and the sectional area at point x are put as 



J'cou. 'i.'ôkyô Math, i'hys. Sao. Vul. HI. p. 174. 



