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SMITHSONIAN MISCELLANEOUS COLLECTIONS 



VOL. 66 



Figures 7, 8, and 9 show the solar-constant values and the solar- 

 contrast values of 1913 and 1914 plotted as functions of the time 

 and also as functions of each other. From figures 8 and 9 the 



Contrast numbers. 



Fig. 8.-^ Variations of solar constant and solar contrast in 1913 ^ 



-120 -100 -'80 -60 -^O -20 +20 -I20 -lOO -80 ^-60 -40 -20 O *20 

 Contrast numbers 



Fig. 9. — Variations of solar constant and solar contrast in 1914* 



increase of the solar-constant values by i per cent corresponds to 

 an increase of solar-contrast values of 1913 and 1914 as follows : 



Change of 

 Change of Solar-Contrast 

 Year Solar Constant Number 



1913: -i-i per cent : -f-17 

 1914: 4-1 per cent : -I- 29 



* Circles represent simple mean contrast numbers, omitting wave lengths 

 0.3737 and 1.008/". Crosses represent weighted means of all wave lengths. 

 Arrows indicate that a certain probability exists that the points marked should 

 be moved in the direction shown. 



