42 



S. Nakamnra aud K. lIoncTa : 



on the lake from Sept. 1st to 3i'd., the positions of the points, 

 where the soundings were made, being determined by means 

 of a compass, furnished witli a small telescope. The result of our 

 bathymétrie survey is given in Plate VIII. The maximum depth 

 is 41 meters, which must be considered to be very great, when we 

 bear in mind that the total surface area is only 6.5 square 

 kilometers. This maximum depth is at the narrowest part of the 

 lake and at a place lying between the stations at Takogawa and 

 Hyakkwan. 



The periods of the seiches in this lake as reduced from the 

 limnograms are tabulated in the following table, in Avhich the 

 number of times when a given period was observed is also given 

 after the sign x following the period in question. 



TABLE 24. 



Station 



Ti 



T:i 



Ta 



T4 



T., 



Hakoné 



Motoliakoné.... 



Uinijiri 



Hyakkwan. . . , 

 Hotokegasaki. 

 Takogawa. . . . 



Ul. 



15.38 X 40. 

 15.37 X 10. 

 15.36x164, 

 15.45 X 29. 



IB. 



6.79x620. 

 0.71 X 39. 



0.57 X 70. 

 0.75 X 73, 



m. 



4.53x433. 

 4.82 X 225. 

 4.54 X 28. 



Ul. 



3.90 X 164. 



Ul. 



3.10x102. 



■ ' ] 



3.12x151. 



Thus we got five periods in all. the weighted means of the above 

 numbers being 



Tj= 15.38 minutes, 



%= G.7G ,, 



T,= 4.63 ,, 



