488 PROFESSOR W. N. HARTLEY AXD MR. H. RAM AGE ON THE SPECTRA 
The Identification of Lines and Bands observed in the Spectra of the Flames 
from the “ Basic ” Process. 
In the region of the rays more refrangible than the strong manganese hne A. 4030, 
no uncertainty is felt as to any line or band. The continuous spectrum extends 
throughout the whole of this portion to the edge of the plate, about \ 3210. It 
fades gradually, except at two places, from X 3705 to 3600 and from X 3581 to 3500, 
where two broad hands occur. These bands were observed in the Crewe Bessemer 
spectra, and in the spectra of manganese and its compounds heated in the oxyhydrogen 
flame (Flame Spectra), ‘ Phil. Trans.,’A, vol. 185, p. 1029. Between X 4030 and 3448 
the only lines detected are the iron lines, which are present without any considerable 
variation of intensity in the oxyhydrogen spectra of iron and its compounds. The 
lines just beyond X 3448 are the pair of potassium lines, X 3447'49 and 3446’49, the 
latter one slightly stronger than the former, and both of them stronger than the iron 
line 3440‘7. 
The iron line X 34434)6 is present in some of the spectra. Between this point and 
the edge of the plate, about X 3210, no iron lines are found either in the Middles¬ 
brough or the oxyhydrogen spectra. Lines of other elements are visible on the 
photographs of several of the Middlesbrough spectra, the strongest being the sodium 
line X 3303, which is really a pair of lines, but they are not distinctly separated 
unless the quantity of substance is very small. The silver line X 3383'0 is present in 
several spectra, and on Plate 26 the second silver line X 3280'8 is seen. On Plate 26 
the second spectrum indicated by 26^, in which the lines are very sharp near the 
edges of the plate, the two copper lines X 3274’1 and 3247 "7 are present, and beyond 
these again is the lithium line X 3233 and the potassium line X 3217'5. There is no 
indication of the sj^ectrum of water vapour ; the strongest lines in this spectrum 
would not, however, fall on the photographic plate used by us. 
The identiflcation of the lines and hands in the visible portion of the spectrum 
is much more difficult. 
(1.) Lines. —Near the more refrangible end of the visible spectrum the manganese 
triplet occurs, eadi line being very strong ; the neighbouring potassium lines X 4044 
and 4047 are also very strong. Next in order are four strong lines with wave-lengths 
4171-5, 4201-9, 4216-0, and 4226-4. 
These lines are not present in the Bessemer spectra froin the “ acid ” process which 
we had hitherto examined, and their identiflcation was not readily accomplished. 
The first fact noticed was that the first and last lines varied in strength independently 
of all other lines in the spectra, and that of the two intermediate lines, 4201-9 was 
always stronger than 4216-0. These two were, therefore, identified with rubidium, as 
they were the strongest lines in the oxyhydrogen flame spectrum of that element. 
The line 4226-4 was identified with calcium, this being decidedly the strongest line in 
