1038 
PROFESSOR W. N. HARTLEY ON 
also overlying M, which is not visible, probably on account of the strong group of iron 
lines at this point. There is also a weak band beyond N, seen as diffused rays in the 
Bessemer spectrum, but which appears as two groups of very line lines in the 
manganic oxide spectrum. 
The following is a list of 87 lines and edges of bands which are common to the 
spectrum of metallic manganese and that obtained from manganese dioxide. The 
spectrum of the metal received only half-an-hour’s exposure, that of the oxide an 
hour and twenty minutes. The bands of the one may be a little wider than those of 
the other owing to the longer exposure. The intense ignition of the oxide certainly 
causes its dissociation. It will be noticed that many lines have been measured as 
iron lines by Fievez and Thalen, Vogel and Thalen, Kayser and Bunge, and by 
Cornu. Some of these are unquestionably manganese lines, others may closely 
approximate, or coincide, in wave-length with iron lines. It is quite certain, after 
careful examination, that the photographs of the manganese spectrum, whether 
obtained fi-om the metal or the pure oxide, contain no iron lines, since all the principal 
lines of this element are absent. 
List of Lines and Bands Common to the Spectra Obtained from the Metal and from 
the Oxide of Manganese. 
Manga¬ 
nese. 
\. 
Description of Spectrum, with Lines 
Manga¬ 
nese 
Description of Spectrum, with Lines 
observed in other Spectra. 
dioxide. 
\. 
observed in other Spectra. 
5855 
Fe, 5855-2, Fievez and Thalen 
5856 
Fe, 5855-2, Fievez and Thalen 
5800 
Fe, 5800 Fievez and Thalj^n 
5800 
Fe, 5800, Fievez and Thalen 
5712 
in.r. edge of weak band 
5717 
m.r. edge of band' 
5022 
Edge of band and apparently a line 
5622 
Edge of band like a line 
Fe, 5623-5, Fievez and Thalen 
Fe, 5623-5, Fievez and Thal^ 
5591 
Edge of band, hazy 
5591 
m.r. edge of band 
Fe, 5591, Fievez and Thalen 
Fe, 5591, Fievez and Thalen 
5571 
Line or l.r. edge of band 
5575 
l.r. edge of weak band 
Fe, 5571-3, Fievez and Thalen 
5478 
Line 
5474 
Edge of band, doubtful 
Fe, 5478 
Fe, 5473-6 , Fievez and Thalen 
5445 
Line, distinct, rather broad 
5443-5 
Nebulous line near edge of band 
Fe, 5446, Fievez and Thalen 
Fe, 5446, Fievez and Thalen 
5438 
Line, sharper and weaker 
5438 
Nebulous line, but sharper 
5402 
Edge of strong band 
5405 
Line or edge of band, strong 
5391 
) Fe, 5392, Fievez and Thalen 
5400 
1 
> Band 
> Band 
5370-5 
) Edge strong 
5368-5 
J Edge of band and of this series 
Fe, 5370-6, Fievez and Thalen 
5347 
5315 
7 Edge of band, doubtful 
) 5? 
5347 
5318 
) l.r. edge of band } x- i i 
f j i 1 1 f very ieeble 
) m.r. edge of band ) 
Fe, 5316, Fievez and Thalen 
' 5270 
m.r. edge of band 
5271 
m.r. edge of band, weak 
Fe, 5269-5, Fievez and Thalen 
Nearly coincident with E 
1 
Coincident with E 
