no. 3 



RADIATION OF THE ATMOSPHERE — ANGSTROM 



157 



In order to compute Qo, a smooth curve was drawn through the observations 

 and values of Qm for m = 1, 2, and 3 were read off from the curve. These 

 values and the value of 8 for the day were inserted in (2) and £0 then elimi- 

 nated between the first and second and the first and third of the equations thus 

 obtained. The results are given in table 19 under the headings Q12, Q13; the 

 mean of these for each day is given under Q K°\ and represents the solar con- 

 stant as obtained for that day by the Angstrom-Kimball method. 



The mean value of all the measurements, reduced to mean solar distance, is 



1.931 ( - £l ii__ (Angstrom scale) or 2.019 (Smithsonian scale). The maximum 



cm. 2 min. 

 deviation from the mean is 3 per cent. 



Finally, Fowle's abridged method was applied to the same observations. 

 Sufficient observations are not available for the elaboration of a special cor- 

 rection suited to Mount Whitney. But from the values of 5, it appears that 

 the transmission over Mount Whitney was about the same as over Mount 

 Wilson, where the average value of 8 is 0.25 ; and the water-vapor pressure, 

 the most uncertain factor, was low (2-4 mm.). Hence it may not be devoid 

 of interest to apply here Fowle's rule as elaborated for Mount Wilson, which 

 is: To the "apparent solar constant" obtained by straight-line extrapolation 

 add 2.7 per cent and as many per cent as there are millimeters in the water- 

 vapor pressure. The results thus obtained are given in table 19 under the 

 heading Qp\ the mean water-vapor pressure is given under p. 



Weighted mean To = 0.0683 



reduced to mean solar distance h = o 0702 



cm.- mm. 

 cal. 



(Angstrom scale) 

 Mean reduced to mean solar distance: Qka 



1.931 (A.), 

 = 2.019 (Sm.) 

 Qf = 1.872 (A.), 



= 1.960 (Sm.) 



cal. 



cm.- mm. 



cal. 



