228 



PROCEEDINGS OF THE AMERICAN ACADEMY. 



concentrated solutions. The two bands A. 580 and X 547 disappear if 

 the nitrate is changed to chloride ; otherwise the nitrate and chloride 

 give maxima in essentially the same positions, although the relative 

 intensities of the bands are somewhat different in the two cases. 



The second, third, and fourth columns of the foregoing table represent 

 the corresponding results obtained by Forsling from Holmberg's neodym- 

 ium preparation,^ by Rech from Muthmann's preparation,^ and by Auer 



1 Zeit. anorg. Chem., 53, 83 (1907). • 



2 Zeit. Wiss. Photographie, Photophysik u. Photochemie, 3, 411 (1906). 



