PART III. EARTH CURRENTS AND EARTH MAGNETISM. CHAP. I. 



755 



We have also determined the relation between the maximal effect of the earth-currents and of the 

 external current-system upon the magnetic elements. 

 We found the following figures: 



May 1 6 



Storm I; duration 1.5"' Storm II; duration 18'" 



o.i 8 0.09 



VECTOR DIAGRAMS. 



Kaaljord. 



1910 



25 V, 



May 27 



Duration of storm 2 h , 

 0.15 



Pert, force 





Fig. 272. 



We have previously determined this relation for some of the storms from 19021903 and found 

 alues varying between 0.12 and 0.52. 



This last investigation therefore serves to show that the small cable-resistance that we employed 

 Deviously did not occasion any essential change in the phenomena. This should therefore justify us in 

 he conclusions that we drew from that material. 



Finally, in this connection, I would touch upon a phenomenon that we observed during this ex- 

 pedition, and which may be of special interest. 



