Morrow — On the Influence of Self-induction, ^c. 

 Principal Lines of Phosphorus. 



619 



BOKON. 



The boron spectrum was obtained by vapourizing boron trichloride. 



Tlie spark emitted a brilliant white light during the passage of the 

 current. 



Only four lines of boron are seen in the photograph, but many lines 

 of silicon and chlorine. This may have been due either to silicon in the 

 boron trichloride or to the boron attacking the quartz flask. 



The introduction of self-induction has evidently no effect on the boron 

 spectrum. 



Principal Lines of Boron. 



Silicon. 



Silicon tetrachloride was placed in the quartz flask, and heated very 

 gently. The electrodes were then sparked in the vapour, and a photograph 

 taken of the spectrum. There was a very brilliant white light emitted by 

 the spark during the passage of the current. 



Twenty lines, apparently due to silicon, appear, and some of these are most 

 characteristic and easily recognized. Of course chlorine lines are also 

 seen, but these may be easily detected by simply superposing a plate of 

 tlie chlorine spectrum on that of silicon tetrachloride. 



Selt'-inductiou has apparently no effect on the spectrum of silicon. 



