14 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I23 



been made, and in particular it should be helpful to carry out a series 

 of observations at some one station using both the ultraviolet and the 

 visible absorptions. 



SUMMARY 



An analytical method has been developed for computing the vertical- 

 path atmospheric ozone from the measurements of atmospheric 

 transmission coefficients at several wavelengths across the visible spec- 

 trum using the absorption of ozone in this region. In the computa- 

 tional procedure a large part of the calculations is carried out once 

 and for all, the evaluation of the ozone corresponding to any one set 

 of observations being a relatively small matter. 



The method also yields information concerning atmospheric haze. 

 The optical densities corresponding to the measured transmission co- 

 efficients are represented in the present vi^ork by four terms. Two of 

 these are the scattering by the molecules of the air and the absorption 

 by ozone. The other two represent the scattering by haze, one a 

 wavelength-independent portion, and the other a term in the square 

 of the reciprocal of the wavelength with unknown coefficient. The 

 values of this coefficient and of the wavelength-independent scattering, 

 in addition to the ozone path, are given by the calculations, and con- 

 stitute information on the character of the optical density of the haze. 



ACKNOWLEDGMENTS 



The eflforts of a number of people have contributed to the present 

 research. The authors gratefully acknowledge assistance received 

 from Alfred F. Moore, Fred A. Greeley, Alfred G. Froiland, Merwyn 

 G. Utter, and Albert M. Pezzuto, and the encouragement and support 

 received from L. B. Aldrich, director of the Astrophysical Observa- 

 tory, Smithsonian Institution, and from the late W. H. Hoover, chief 

 of the Division of Astrophysical Research. Grateful acknowledgment 

 is also made to Verner Schomaker, of the California Institute of 

 Technology, for valuable discussions and suggestions. 



