1046 
PROFESSOR W. N. HARTLEY OH 
converters sliow the green group y when being heated with coke, one with a new 
lining never does. The green lines of manganese he believed to be the constituents 
of the groups /3 and y of Lielegg’s so-called carbonic oxide spectrum and also the 
violet line of manganese, the line 77 , attributed to carbonic oxide. 
The flame from the tap-hole of a blast furnace could display the same spectrum as 
that of the Bessemer flame just as well if the spectrum be composed of lines of 
manganese and iron as if they were due to carbonic oxide. At the recpiest of 
Kupelwieser, Schoffel analysed the fume which rises from the neck of a converter 
iluring the “fining” period and found it to be a manganese and ferrous silicate. • 
SiOg = 34*86 
MnO = 48*23 
FeO = 16*29 
99*38 
This is an indication of manganese and iron being concerned in the formation of the 
spectrum (‘Oesterreichische Zeitsch.,’ No. 29, p. 227, 1868). 
The investigation, carefully and laboriously carried out by Dr. Marshall Watts, 
led him to the conclusion that the lines visible in the Bessemer-flame spectrum are 
mainly due to manganic oxide, not to metallic manganese, as had been stated, nor to 
carbon. When manganese chloride, carbonate, or oxide, such as the mineral 
pyrolusite, is heated in the oxyhydrogen flame, a very brilliant banded spectrum is 
obtained which is for the most part coincident with the Bessemer spectrum. 
Observations were further made on the spectrum of the flame obtained on adding 
spiegel-eisen to Bessemer metal, on the temperature of the flame at diflerent stages 
in the process, and on different spectra obtained by the employment of different kinds 
of iron. 
Accurate determinations were made for the first time of the wave-lengths of lines 
observed in the spectra of the Bessemer flame of spiegel-eisen, and of manganese 
dioxide. 
The fact that six lines of iron were present in the Bessemer spectrum was estab¬ 
lished, and considered to be a proof that iron may exist as vapour at a temperatui*e 
below its melting-point, since certain experiments led to the conclusion that the 
Bessemer-flame was not hot enouoh to melt wroueht-iron. 
This work of Marshall Watts is the most exhaustive investigation of the subject 
that has up to the present appeared. In 1874'^^ Greiner observed in tlie flame from 
highly manganiferous pig-iron the spectrum of manganese as figured by Wedding. 
During the meeting of the British Association, at Sheffield, in 1879, I made a 
short examination of the Bessemer flame with a small direct vision spectroscope, at 
the works of Messrs. Brown, Bayley, and Dixon ; I also examined the flame of 
* ‘ Revue Umverselle,’ vol. 35, p. G23, 1874. 
