Harmonie Analysis cf Tidal Obs ryations. 5 



Obsarvatîry Long'. E. Lat. N. 



Iwasaki 139° 54' 40° 35' 



Ayukawa 141 31 38 18 



Otaru 141 1 43 13 



Hanasaki 145 35 43 17 



Among these observatories, there are a few whose sites have 

 been changed, because of some trouble that was found after the 

 work of registering was begun, or for some other reason. With 

 respect to these, the special reasons will afterwards be given, when 

 we describe about each station. 



All these observatories, except the two temporary ones at , 

 Yokohama and Kobe, belong to the Land Survey Department and 

 are permanent in character. 



Description of a Tide Observatory. 



According to the information received from the Land Survey 

 Department, the construction of the observatories and the instru- 

 ments set in them are the same in their general features at 

 each place, and only slight modifications are made to suit the sites 

 selected. Thus the description of one observatory will be given 

 as a specimen. As the writer had the opportunity of visiting the 

 observatory at Aburatsubo, it is chosen here for description. 



The tide observatory at Aburatsubo is built of brick and lined 

 with wood inside. Its size is very small, leaving only a space of 

 forty square feet inside, and it is divided into two parts. One of 

 them is larger, measuring about twenty-five square feet, and serves 

 as the instrument room. The other portion is considerably 

 smaller and serves as the clerk's office. The outer doors open into 

 the clerk's room and when we open another pair of doors opposite 

 to them, we are admitted into the instrument room. As that 



