CYCLOGRAM ANALYSIS 



33 



the longer period lengths. Suspected long periods are often sought by in- 

 tegrating several successive values from decidedly less to decidedly more 

 than the suspected length and observing whether the cycle amplitude in the 



1833 



1844 



1855 



1866 



1877 



1888 



1899 



1910 



192 



844 



855 



866 



877 



1888 



899 



1910 



100 



932 



Sunspot Nos. 



J_ 





 Scale 



Fig. 15 — Plot of sunspot data to show changing place of 11.4-year 

 maxima in successive 11-year intervals. 



plotted means increases to a maximum and then falls away, as in figure 16. 

 This is called successive integration and can be made very effective over short 

 ranges. 



