electro-magnetic fields on the spark spectra of gold, etc. 85 



Wave-length 



A. 4041 "1.) These two lines show a distinct widening — but are too weak 

 401 6 -2./ to analyse. 

 3898-0. This line is a triplet, the two outer members of which 



vibrate perpendicular to the lines of force, and the inner 



one parallel thereto. 

 3804*2. This line is widened, and, on analysing it, although it is 



rather weak it seems to be a triplet, with the three 



components vibrating like A 3898. 

 3633"4. This line is widened, but it is too weak to analyse. 

 3586 - 6. This line appears as a widened reversal or doublet. The 



reversal is not sharp nor well defined. 

 3553*7. This line is widened, but it is also too weak to analyse. 

 3122 - 8. This is a triplet; the two outside members of which 



vibrate parallel to the lines of force, and the middle 



one perpendicular thereto. 

 3122--6. A weak line which appears to be widened, although this 



is not easy to make out on account of its weakness, and 



also particularly its nearness to X 3122-8. 

 3029-3. This line is a doublet or reversal. Tho two members are 



quite clear, sharp and well defined. 

 2995-1. A somewhat broad line, which seems to show signs of 



widening. 

 2990-3. The line is weak, and seems to become a doublet or reversal 



— but the division is not very clear or well defined. 

 2913-6. This line becomes a triplet, the two outside members of 



which vibrate perpendicular to the lines of force, and 



the inner one is parallel thereto. 

 2825*5. It seems to be slightly widened, but it is too weak to 



analyse. 

 2820-1. A rather broad line, which seems to be slightly widened, 



but it is too weak to analyse. 

 2802-3. This line shows signs of widening. 

 2748-3. This line becomes a triplet, the two outside members of 



which vibrate perpendicular, and the inner one parallel, 



to the lines of force. 

 2676-5. This line becomes a widened doublet or reversal. The two 



divisions are sharp, clear and well defined. 

 2428-1. This line also becomes a widened doublet or reversal. The 



two members do not appear to be so sharp nor so clearly 



defined as those of 3029-3 and 2676-5. 



With regard to the lines which are divided into triplets, of 

 those arising from 4792*8, 4488*4, 4065-2, 4053, 3898, 3804*2, 

 2913 - 6, 2748 - 3, the two outer members vibrate perpendicular to 

 the lines of force, and the inner one parallel thereto. Whilst of 

 the triplet arising from 3122*8 the two outer members vibrate 

 parallel, and the inner one perpendicular, to the lines of force. 



It may be mentioned here that the air lines at 4600 and 



