>46 E. HUNTINGTON SOLAiR HYPOTHESIS OE CLIMATIC CHANGES 



extent to which the number of storms during years of many sun-spots 

 exceeds or falls short of the number during years of few spots. It em- 

 bodies the same material as figure 7. The only difference is that the per- 

 centage of excess or deficiency has been used instead of the actual number 

 of storm centers, and lines have been drawn so as to divide the entire 

 area into four parts of approximately the same area. The interpretation 

 is simple. The heavy black shading means that when sun-spots are 



i 





Over +16 per cent. 

 to +16 per cent. 

 to —8 per cent. 

 Less than —8 per cent. 



LEGEND 



The figures indicate the percentages by which 

 the average rainfall of the years of maximum 

 sun-spots exceeds or falls short of the average 

 of the years of minimvim spots. The mean pre- 

 cipitation since records have been liept is taken 

 as 100 per cent. 



FxGuiii: 17. — Comparative Precipitation of Nine Tears of Maximum Sun-spots and Nine 

 Years of Minimum Sun-spots in Percentages of the mean Precipitation 



numerous storms are abundant ; the dotted areas indicate that when spots 

 are numerous storms are comparatively few. The other two kinds of 

 areas — that is, those shaded by means of lines and those left unshaded — 

 indicate that the amount of storminess does not change greatly, although 

 where the lines occur there is a slight increase in storms at sun-spot 

 maxima and in the other areas a slight decrease. 



Figure 17 is constructed according to the same method as figure 16 

 except that rainfall instead of storminess is used. It is based on all the 



