MAGNETIC SURVEY OF JAPAN FOR THE EPOCH 1895.0. 133 



five points in each, distribnted so as to cover different quarters 

 of the countries. In Great Britain the Central Stations of the 

 Districts I, III, V, VIL and IX are taken as representatives. 

 The last figures of numbers exceeding 20. in those tables will 

 be slightly affected by taking into account the difference of 

 principal curvatures of the earth surface in various latitudes, but 

 since their proljable errors come to the same order of magnitude 

 in such cases, the mean radius is used for simplicity. 



