EEPORT OF THE SECRETARY. 



77 



Table 1. — Cocffiviciits of (ituiosplKrir tfuiisniission for radialion frviii zenith 



sun. 



Wave length — 



Date 



1904. 



September 22 



October 5. 



October 21 



November 16... 



1'.I(I5. 



February 7 



June 3 



June 22 



June 27 



Mean 



0.40 0.45 0.50 0.60 



0.70 



0.80 1 0.90 ; 1.00 : l.'A) 



Transmission-coefficients for unit air mass. 



0.55 

 .48 

 .60 

 .54 



.53 

 .45 



.48 

 .45 



.90 

 .85 



81 



0. 88 0. 89 



.84 ! .86 



.93 .94 



.88 I .90 



822 



.85 

 .84 



.84 



1.60 



0.90 



.98 

 .91 



.92 



The mean re.sults will be found to lie extremely near the corresponding ones 

 for the year 1903—1, so that no further discussion of them seems necessary. 



In Table 2 are given the values computed for the solar constant of radiation 

 outside our atmosphere, in continuation of the series published in former years. 

 The method of computation and the a.s.sumptions on v>'hich it is based have been 

 given in preceding reports and are substantially th'^se employed by you many 

 years ago at Allegheny. 



Table 2. — Values of the solar constant of radiation outside the earth's atmos- 

 phere from Washington o1)serrations. 



