Seiches in Some Lakes of Japan. 23' 



taken in our countiy. As already stated in the introduction, we 

 had two limnimeters at our disposal, one of the Sarasin type and 

 the other of our own design. We had first to study these instru- 

 ments, to see how to construct the water tank, and how to connect 

 it with the lake, etc., and to this preliminary work we were obliged 

 to sacrifice the first few days, so that our regular observations must 

 be said to have began on the 7th. of August. The second series 

 extended from the 6 th of September to the last day of that month. 

 The number of stations was 14 in all, for the names and positions 

 of which see tlie map given in Plate VI. 



In the first series of observations we permanently set up at 

 Imazu, a Sarasin portable limnim.eter modified however, as has 

 aleady been described, by dispensing with the rack and pinion, and 

 by fixing the recording cylinder vertically. Afterward this latter 

 was replaced by a Richard's cylinder. A portable limnimeter of 

 the ''N" type was carried round the lake from one station to 

 another, being set up at each station for from one to three days. 

 In the second series, on the contrar}^, both instruments were 

 carried about, but the number of stations was limited to five, 

 namely Imazu, Shiotsu, Otsu, Nagahama and Hikone. 



We shall- now- give the results of observations obtained at the 

 several stations. 



Chikubushima. 



Chikubushima is an island in the northern part of the lake. 

 The observations at this place lasted only 18 hours, and we got the 

 following three different motions. The numbers in the first column 

 are the periods expressed in minutes of time, and those after the 

 sign X are the numbers of Avaves used in calculating the corre- 

 sponding-periods. 



