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XXXIX. On the Spectrum of the Bessemer-flame. 

 By Professor Lielegg*. 



To the Editors of the Philosophical Magazine and Journal. 



Gentlemen, 



TWO papers have been communicated to the Vienna Imperial 

 Academy by Professor Lielegg, of the National Upper Prac- 

 tical School at St. Polten, on the Spectrum of the Bessemer- 

 flame, which contain an interesting examination of that spectrum, 

 and therefore of that produced by the gas known as carbonic 

 oxide, to the combustion of which the flame owes its origin. I 

 beg to offer you the enclosed translations of the notices of those 

 papers. 



I am, Gentlemen, 



Your obedient Servant, 



W. T. Lynn. 

 Greenwich, September 21, 1867. 



The flame which issues during a " charge M from the Bessemer- 

 oven shows, when it is examined with a spectral apparatus of 

 even the simplest kind, different bright lines which distinctly 

 stand out from the continuous spectrum, which forms, as it were/ 

 the background. 



Besides the lines due to sodium, lithium, and potassium, which 

 are visible at the end of the period of slag-formation, groups of 

 lines make their appearance during the combustion-period, which 

 attain their greatest intensity of light at the commencement of 

 the cooling-period. They extend from the sodium-line up to the 

 blue strontium-line, or even a very little beyond it, and divide 

 this space into four fields of equal size. The end of the first 

 field, which is situated immediately close to the sodium-line, is 

 indicated by a bright yellow line ; but no other lines can be per- 

 ceived in it, by reason of the extraordinary brilliancy of the light. 

 The second field, in contact with this, lies in the greenish-yellow 

 part of the spectrum, and contains, in its more distant half, three 

 equally broad greenish lines, of which the third is the brightest, 

 and defines the termination of the field. The third or follow- 

 ing field contains four greenish-blue lines, of which the last but 

 one is the brightest, and the last bounds the field ; the lines 

 are equally distant from each other, and occupy two -thirds of the 

 field, so that between the third line of the second field and the 



* Read at the Meeting of the Mathematical and Natural- Science Class 

 of the Imperial Academv of Sciences at Vienna, January 31, 1867. 

 Translated by W. T. Lynn, B.A,, F.R.A.S. 



