94 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 65 



of Kansas and Oklahoma, as these ceremonies are now extinct among 

 the Foxes proper. 



The accompanying photographs are those of a Fox sacred bundle, 

 with its contents, which is now in Berlin, and of a Fox Indian. 



STUDIES OF SOLAR RADIATION 



Mount Wilson work. — The Astrophysical Observatory continued 

 its observations on Mt. Wilson, Cal., for the purpose of measuring 

 the intensity of the sun's radiation, as it is at the surface of the earth, 



Fig. 89. — Balloon Pyrheliometer. 



and the losses which it sustains in passing through the atmosphere, 

 so as to permit the determination of the mean intensity outside the 

 atmosphere, which is called the solar constant of radiation. As 

 shown in former years, solar radiation is really not strictly constant, 

 but is variable. The observations were made at Mt. Wilson on 

 every favorable day throughout the period of the stay of the expedi- 

 tion, from May until November, in order to study the progress of 

 this variability of the sun. 



In connection with this work, the observatory was equipped with 

 a tower telescope of 75 feet focus in the autumn of the year 191 3. 

 This instrument has been employed for the study of the distribution 

 of light over the image of the sun, and the results indicate that this 



