ON WAVE-LENGTH TABLES OF THE SPECTRA OF THE ELEMENTS. 279 



Table of Standard Wave-lengths — continued. 



t 



Not recommended as a standard in the arc. 



Fe 5603-180 | 



Ca 5603-080 I 



Fe 5602-995 I 



In the arc this line is difEuse on one side. 



edge of the band-like line. 



The solar line corresponds to the 



