12 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. // 



Increase of SOLAR RAD. from below 1.931 to above 1.960 



Pressure same day Sammer half year 



Pressure 1 day later Summer half year 



Pressure 2 days later Summer half year 



Fig. 7. — Mean pressure differences resulting from an increase in 

 solar radiation from below 1.931 to above 1.960, to 2 days later, 

 summer half-year. Units in hundredths of an inch. 



