80 



Mr. C. J. Lundstrom. 



there were observed two other faint lines. The group 7 consists of 

 three bright bands that fade away towards the red. In the group B 

 there are four equally bright bands that seem to fade towards either 

 side; the shade behind this group is not so distinct as behind 

 the groups (3 and 7. 



The other bands of the spectrum, forming the group e, do not 

 appear so distinctly. Usually e x and e 2 appear, but it is very difficult 

 to determine with accuracy their positions, on account of their short 

 duration and their want of brilliancy. I have not been able to put 

 down the position of e 3 more than twice and it has been impossible 

 to discover the lines and bands in the violet part of the spectrum. 



After the disappearance of the blue flame, there were only the Na 

 and Li lines visible and the bands ft and 7 of this spectrum. A 

 minute after the beginning of the "boil," /3 and 7 appeared, and 

 also traces of 8, and a minute afterwards the spectrum was fully 

 developed. Lastly appeared the bands of the group e, and these 

 were the first to disappear when the proportion of carbon was 1*1 and 

 1*2 per cent. Then £3 disappeared before the other lines of the group 

 when the carbon was about 0'70 per cent., and generally all the 

 groups e> had vanished when the carbon had passed down to 0*40 and 

 0*35 per cent. 



On warming the converter before the " blow " there appear gene- 

 rally, here as elsewhere,* the principal Mn 2 3 bands (/3i, 71, 72, 73, and 

 and also the Na and Li lines, but on the other hand, when the 

 furnace had been relined, there appeared only the Na and Li lines. 

 If the instrument is directed towards the flame which arises from 

 the flow when the finished Bessemer metal is tapped from the con- 

 verter, one may perceive a Bessemer spectrum which is almost 

 brighter, and more distinct than during the previous " blow." The 

 group e has several bands and appears very distinctly along with 

 other groups, and this is the case even when the "blow" has con- 

 tinued so long that several bands have disappeared before the con- 

 verter is turned down. 



At these works the Bessemer pig-iron contained — 



1*80 per cent, of combined carbon, 

 2*49 ,, graphite, 

 0*91 ,, silicon, and 

 2*32 manganese. 



The Domnarf Spectrum. 



I have only once observed the Bessemer spectrum at these works, 

 and have no accu? ate measurements recorded. It differs but slightly, 



* ' Wien Ber.,' vol. 56, p. 26. 



