no. 4 



SOLAR RADIATION ABBOT, POWLE, AND ALDRICH 



The following table gives the results of nearly 700 measurements 

 of the solar constant of radiation as published in Vol. Ill of the 

 Annals above cited : 1 



Table i — Mean Solar Radiation Outside the Atmosphere 



Expressed in standard 15 calories per square centimeter per minute at mean 



solar distance 



The Washington results fall a little higher than the others. This 

 may be due, in part at least, to the fact that most of them were made 

 while sunspots were numerous, for our investigations at Mt. Wilson 

 indicate that high values prevail when sunspots are at a maximum. 



x We note here the following errors which have been found in Vol. Ill of 

 the Annals, partly by ourselves, and partly by others who have kindly com- 

 municated them : 



Page 119, figure 11, Nov. 8 misplotted. Should be 2.004, see p. 105. 

 Page 129, table 42, Nov., 1908, for 1.947 read 1.961. 



Under " Mean," for 1.936 read 1.945. 

 Page 130, figure 16, Nov., 1908, for 1.947 plot 1.961. 

 Page 132, table 43, 14th column, for 592 read 607; for 1,338 read 1,363. 



16th column, for — 4.4 read — 6.6; for — 2.1 read — 3.9. 

 Page 134, table 44, In 1908, for 1.936 read 1.945. 



In " Total," for 1.9315 read 1.9333. 



Under " General mean," for 1.932 read 1.933. 

 Page 138, table 47, Wave lengths, for .5995, .7200, .8085, .9215, 1.0640, 1.1474, 



1.2230, 1.3800, read .5980, .7222, .8120, .9220, 1.0620, 



1. 1460, 1.2255, 1.3770. 

 Page 162, table 58, We withdraw the conclusion based on this table as to the 



direction of the change of distribution of solar radiation 



with change of " solar constant." A great body of as 



yet unpublished experiments leads to modifications. 

 Page 201, table. Under " Intensity," for 1,338 read 4,160. 



In regard to the matter mentioned by Kron (Vierteljahr. Astron. Gesell. 49 

 Jahr., p. 68, 1914), we included in our statement, page 127, two days of 191-1 in 

 which the Bassour work was very satisfactory, but the Mt. Wilson work was 

 not. We regret the errors in our figure 15 mentioned by Kron. The principal 

 one is the omission of August 31. Two others are misplotting the Mt. Wilson 

 values for September 4 and September 9. All the corrections improve the 

 appearance of figure 15. See page 122 for the true values. 



