76 



AKSEL S. STEEN. TERRESTRIAL MAGNETISM. [NORW. POL. EXP. 



e E 



1897. April 18 (M1764 0'076523 



19 0-11756 0-076385 



Mean 0'11760 0'076454 

 According to the table given on page 69, the 



mean found in Hamburg in 1893, is . . 011799 0'076800 



Mean 0'11780 0'076627 



As regards the values of n for magnet VI, I will refer the reader to 

 what is said on this subject on page 70, merely adding that this magnet 

 was not used for deflections with the double needle as deflected magnet 

 before September 30th, 1893, and therefore the values of /.i found for 

 this mounting of the apparatus in Wilhelmshaven in 1897, have been exclu- 

 sively used. 



It was not possible to check the constant C during the expedition, 

 a knowledge of the horizontal intensity determined by the aid of another 

 instrument being required for such a check. I have therefore taken the 

 mean of the values found in Hamburg in 1893 and in Wilhelmshaven in 

 1897, in the cases in which the small declination-needle has been used as 

 deflected magnet, while we have only the determinations in Wilhelmshaven 

 in 1897, in the cases in which the double needle has been used as deflected 

 magnet. 



The following table gives a summary of the final values of the constants 

 /.i and C, used in every case for the reduction of the observations: 



When the expressions for direct employment in the formulae, log Cp and 



rt 



log - , are calculated by the values in the above table, it will be found that 



