=;i8 HIRKFI.AM). TIIF NORWFI.IAX At:RORA POLARIS KXPKDITIOX, igO2 1903. 



These numbers are deduced from the curves giving the storminess of each five day period. In 

 these smother! curves there may be an error in the determination of the actual time of occurrence of 

 the maxima. 



In curve . /, tig. 190 the variation of storminess is represented for each (lay during the period of 

 observations. The curve represents the n/isoliilc storminess S" t or .S' w lor Axeloeii. The curve for the 

 total storminess would not he essentially different. 



In the following table are given the most marked maxima, the principal maxima belonging to the 

 two groups arc- marked in the third column. 



I'AliLK XC. 



The two groups show a characteristic difference; each of the maxima of the first group consists 

 mainly of a single top, those of the second group consist of pairs. This fact must strengthen the 

 assumption that the maxima within each group are closely related to one another. In the fourth column 

 are given the intervals between successive maxima. The average period becomes 29.1 days, or about 

 the same as found from the five-day curve-. There seems no interpretation of the results possible leading 

 to a period of less than 29.1 days. 



Ihi period found is very nearly equal to one synodic month, as the time from one opposition of 

 the moon to the next is 29.53 days. This coincidence would naturally suggest a connection between 

 the polar storms and the position of the moon in relation to the sun. 



On the other hand we know that the polar storms are closely connected with the conditions existing 

 on the sun, and this connection mu>t point to the rotation of the sun about its own axis as the cause 



