300. J. M. Silliman—Examination of the Bessemer Flame. 
The green streaks in the flame are most intense when the 
manganese spectrum is brightest; and as the color of the flame 
when the spiegeleisen is added is also green, we are led to 
suppose them due to the presence of manganese 
On two occasions simultaneous observations were made with 
the spectroscope and the colored glasses; but with the exception 
of that just mentioned, and the changes at the commencement 
and termination of the blow, no striking coincidence was noticed. 
IL Zeamination with the Spectroscope. 
The science of spectrum analysis is yet in its infancy, and 
there has been no scientific investigation, perhaps, which has 
been more contradictory in its results than that of the Bessemer 
flame. The first application of the spectroscope to the analysis 
of the Bessemer flame was made in 1862 by Dr. Roscoe at the 
works of Messrs. John Brown & Co., in Sheffield. Soon after 
this it was in constant use in Brown's works for controlling the 
process. It was next introduced at Crewe, and from there said 
to have been taken to Seraing, in Belgium, in 1865. 
the field of view, while the spectrum with which it was tobe 
compared was seen immediately below. The spectrum of the 
flame was thus compared with the following spectra :— 
1. Spectrum of electric discharge in carbonic oxyd vacuum. 
2; = * strong spark between silver poles in air. 
Cu ee oe oe oe 74 iron oe 
4. 6“ “6 6c ““ a 66 $62 246 hydrogen. 
5. Solar spectrum. 
6. Carbon spectrum—oxyhydrogen blowpipe supplied with 
olefiant gas and oxygen, 
The coincidences observed were very few, and totally failed 
_ to explain the value of the Bessemer spectrum. h 
the well-known carbon spectrum did not occur at all, either as 
bright lines or absorption bands, nor was any coincidence ob- 
served between the lines of the Bessemer spectrum and those 
of the carbonic oxyd vacuum tube. The lines of lithium, so- 
dium and potassium were strongly marked and identified with 
certainty. He found that three fine, bright lines between E 
and 0, shown on the plate at 663°, 67°, 674°, coincided with 
those of iron; and in place of the red hydrogen line O, he dis- 
