NO. 2 



SOLAR CHANGES ABBOT 



yet the correspondence of the two groups is not exceptionally close. 

 Figure 4, which was prepared some years ago to represent the 

 relationship between solar constant values and sun-spot numbers, 

 from all of the Mt. Wilson, Calama, and 2^Iontezuma observations 

 at that time available, indicates that the increase of solar radiation 



Soldr Constdnt . Selected Pyrheliometry - 



. Sun spots ■ 



Fig. 2. — ^Montezuma observations, all months, 1920 to 1925. 



attending a given increase of sun-spot numl^ers is decidedly greater 

 when the total spottedness is small than when it is large. If this 

 consideration is kept in mind in examining figure 3, it will be seen, 

 in part, why the correspondence of the two curves is less marked 

 than perhaps might have been expected. 



However, a new, and, as it seems to me, very important consid- 

 eration also influences the relationship between the two ciu'ves of 



