198 



SMITHSONIAN MISCE[J.ANEOUS COLLECTIONS VOL. 7O 



Figure 'J2. Curves in consecutive twelve-monthly smoothing for the air 

 temperature (according to Arctowski), surface temperature (I, V, VI, X). 

 P: monthly mean of the daily number of prominences according to observa- 

 tions in Catania. M : degree of disturbance of the three magnetic elements in 

 Potsdam. Curves P and M are inverted. All curves indicate the consecutive 

 twelve-month smoothed means. 



