AKSEL S. STEEN. 



[2nd. arc. EXP. FRAM 



which shows with all the clearness desirable that the change in the 

 magnetic moment of magnet V took place before the observations at 

 Station IV in the summer of 1902 were begun. 



As the value of the constant, G, which is independent of the mag- 

 netic moment of the magnet concerned, I have employed for Stations I, 

 II, and in, 1899—1901, the mean value given in the table on p. 29. 



As the constant /.i, according to the above explanation, must be 

 assumed, as far as magnet V is concerned, to have remained more or 

 less unchanged during these three years, I have employed the mean of 

 the values found at Wilhelmshaven in 1897 and 1898. I have used 

 the corresponding mean for magnet VI, on the othei' hand, only for 

 Stations I and II, and have assumed the value of fi found at Potsdam 

 in 1902 to be the right one for Station III. 



In deflection observations at Station 11 on the 26th July and 3rd 

 August, 1900, the double declination needle, P, was used as deflected 

 magnet, instead of the small needle, L, usually employed, whereby both 

 C and |H acquired a slightly different value. In the determination of the 

 constants of the instrument at Wilhelmshaven in 1897, however, ob- 

 servations were also made with this arrangement of the apparatus, 

 whence it appeared that the following correction must be added to the 

 value of log C/.i for needle L, when P was employed as deflected 

 magnet : 



Correction 



For magnet V, distance E, —0.00599 



- VI, — E, —0.00725 



The correction proved to be practically the same for both positions, 



P, and' P,\ 



I have thus, for the first 3 stations, been able to give for calcula- 



G 

 tion the following values for log- and log Gfi 



' Nansen Expedition, T. M. p; 70. 



