ATMOSPHERIC ELECTRICITY IN HIGH LATITUDES. 



87 



An uncertain result is obtained when the observations are divided according to the 

 amount of cloud. For the whole year and for two of the separate months the clouds 

 appear to have a direct influence on the radio-activity, but during the other four 

 months there does not appear to be any relation between the two. 



TABLE XXII. Radio-activity and Clouds. 



The direction of the wind appears to have an influence on the radio-activity, for 

 the latter is at a maximum with a south wind and a minimum with a north wind. 

 It is very questionable if this is a real effect or only a re-statement of the relation 

 between radio-activity and a rising or falling barometer, for every case of a north 

 wind was accompanied by a rising barometer and nearly every case of a south wind 

 by a falling barometer. That it is not the other way about is seen from the fact 

 that observations taken with no wind show an unmistakable relation between the 

 radio-activity and a rising or falling barometer. 



TABLE XXIII. Radio-activity and Wind Direction. 



No relation between the radio-activity and potential gradient can be detected 

 either in the separate months or the whole year. 



TABLE XXIV. Radio-activity and Potential Gradient. 



