MAGNETIC SURVEY OF JAP AX. 233 



Appendix B. 



Complete Lists of Observations made. 



The followinf»- lists contain all the o1)servations made during 

 the survey, together with the dates and hours at which they were 

 taken. The first list contains the Dips, the second the Horizontal 

 Forces, and the third the Declinations. 



The only point which calls for remark is in connection with the 

 tabulation of the Horizontal Forces. It will be noticed that fur the 

 stations of the Northern Party, an extra column headed Mo is added. 

 This gives the magnetic moment of the magnet reduced to 0° C. The 

 reductions were made in accordance with the table of corrections sup- 

 plied by the Kew authorities along with the magnetometer. A glance 

 down the column will show that during the survey the magnet has 

 been subject to a gradual diminution in moment. This is no doubt 

 due largely to the jolting experienced during travelling. On two 

 occasions a somewhat sudden change seems to have occurred — namely 

 between Hakodate and Sapporo, and at Ebisu. In the farmer case 

 the magnetism of the steamer may have had a permanent effect ; 

 while in the latter the cause is no doubt to be traced to the excep- 

 tionally high temperature at which the experiments were made. In 

 the circumstances of the case, it is quite probable that the tempera- 

 ture coefficients may have become altered during the survey ; and that 

 the table of corrections drawn up at Kew may no longer apply. At 

 Ueda, the value of Mo differs by one-half per cent, from the values 

 at contiguous stations — much too large a discrepancy to be accounted 

 on any other ground than that of a bad observation. Fortunately 

 Ueda, being in a very hilly and volcanic district, cannot be regarded 

 as an important station. 



