18 



FLUORESCENCE OF THE URANYL SALTS. 



uncertainties inevitable in the attempt to locate the crests of such 

 broad bands. Of this band, which occupies the region lying, roughly, 

 between 0.4650 /x and 0.4750 fj., only the less-refrangible edge is seen, 

 the other side being more or less cut off by absorption. Its apparent 

 distance from band 7 is thus reduced. 



(4) In some cases there is sufficient evidence of resolution to enable 

 the location of two or more crests. Further evidences of complexity 

 will be found in the spectrophotometric study of these spectra, to be 

 considered in a subsequent paragraph. 



TABLE 7. Fluorescence bands of the double sulphates. 



