PART I. ON MAGNETIC STORMS. CHAP. III. 165 



In Europe as a whole, the conditions are slightly disturbed from 23** on the 24th to 5*" on the 

 25th. There are especially distinct perturbations about midnight, and from 2'' 30"' to 4''. We thus see 

 that the conditions there are in the main connected with the polar storms at the Norwegian stations. 

 If we look at the curve for the declination, we see, moreover, that exactly at the time when the brief, 

 powerful perturbation is occurring in America, there is a perturbation in Europe with very much the 

 same course; it commences exactly at 3'' 15, increases to a maximum, which occurs at 3 h 2i m , and 

 then slowly decreases until about 4'', when it is at an end. 



At Tiflis, Dehra Dun, Batavia and Zi-ka-wei, this perturbation in the main occurs simultaneously 

 with, and runs a course similar to, the perturbation in America. It occurs in H only. 



The field of force is shown in two charts for four different hours. 



TABLE XXIV. 

 The Perturbing Forces on the 25th December, 1902. 



TABLE XXIV (continued). 



TABLE XXIV (continued). 



