84 



Mr. C. J. Lundstrom. 



Tn addition there appeared the Li and Na lines, the bands" 6277 — 

 6179, A and 7l . 



The pig-iron contained — 



0*89 — 098 per cent, of silicon, 

 1*78 — 2*14 ,, manganese, 

 0*025 „ phosphorus, 



and traces of sulphur. 



Spectra for Comparison. 



The Manganese Oxide Sjiectrum. 



Simmler proved that compounds of manganese heated in a Bunsen 

 name give a band spectrum. Lichtenfels and Watts gave evidence 

 of the Bessemer spectrum being for the most part derived from 

 manganese oxide. In order to ascertain which lines were to be 

 attributed to Mn 2 3 , I examined the spectrum of manganese oxide 

 belonging to the department of physics in the University of Upsala. 

 Following the method of Watts, I used pure manganese chloride on 

 a platinum wire in the oxyhydrogen flame. The spectrum observed 

 agreed very well with the spectrum described by Watts and Lecoq* 

 But Lecoq has described three manganese oxide spectra, obtained by 

 passing the electric spark of an induction coil from a platinum 

 electrode through a solution of pure manganese chloride, which 

 formed the negative pole. 



The spectrum obtained with the short spark is a compound one, 

 consisting of both lines and bands. The line spectr am, however, is 

 more developed and agrees more closely with Thalen's manganese 

 spectrum. He also obtained the same spectrum by making use of 

 a moderate sized spark nearest to the negative pole, but at a short 

 distance from the surface of the fluid it gradually passed into the 

 spectrum the position of the lines of which are given in the table of 

 wave-lengths. It contains both lines and bands. Some of the lines 

 are absent, and several new bands have appeared. Lecoq's third 

 manganese - oxide spectrum may be observed when manganous 

 chloride is heated in a Bunsen flame. It consists of the most 

 important bands of the last-mentioned spectrum. 



Watts, in his table of the Mn 2 3 spectrum, has given the positions 

 of only the bands and lines which fully agree with his Bessemer and 

 Spiegel iron spectra. It is, therefore, only natural that I should 

 have observed by means of the same method a greater number of 

 lines in the green region of the spectrum. 



* ' Spectres Lumineux,' par Lecoq de Boisbaudran, Paris, 1874, p. 110. 



