Properties of Pure Substances : Nitrogen. 21 



8. — D. Halfway between the two lines. Mean, \=5893. 

 Rowland, Phil. Mag. 1889. Compared with sodium 

 flame. 

 9.— Picked up from Chart. \= 5709*8. 



10. — Barium (7). From flame-spectrum of Ba (1ST0 3 ) 2 . 

 B.A. Report, 1884. Liveing and Dewar. \ = 5534*3. 

 A bright line. 



11. — Magnesium, X=5528. Rowland's map and spark- 

 spectrum. 



12.— Thallium («), X.-5349. B.A. Report, 1885. Liveing 

 and Dewar, and de Boisbaudran. Got from flame- 

 spectrum. 



13. — Iron, 5328*2. Rowland's map verified by spark-spec- 

 trum. A good line. 



14. — E. A,= 5270. Rowland's map, a big double. Picked 

 up at first because it was found from Schellen's map that 

 it was between two cobalt lines and near an iron line. 

 These lines were seen in their proper relative places in 

 the spark-discharge from iron and cobalt. This was one 

 of the first lines identified. 



15.— b u 5183-798. Rowland, Phil. Mag. Verified by mag- 

 nesium-spectrum. One of the first lines got. 



1 6. — \ = 5041-5042. Picked up from Rowland's map. Veri- 

 fied by finding from B.A. Report that it was an iron 

 line and then confirming by spark-spectrum. 



17. — \=4957*6. Picked up and verified as in the last case, 



18.— \ = 4920*6. Ditto. 



19.— F. A = 48b , l-492-4859-929. Rowland's map confirmed 

 by vacuum-tube. 



20. — Bismuth. X — 4752. B.A. Report, Thalen, and Huggins. 

 From spark-spectrum. Not very good. Evidence as to 

 identification, its general relation and appearance. 



21. — Bismuth. X = 4724*5 . A very prominent line. Evi- 

 dence and authority as in last case. 



22. — Bismuth. \ = 4705. Ditto. These lines cannot be 

 mistaken. 



23. — Strontium blue line. X = 4607. From flame-spectrum . 

 B.A. Report, 1884. Liveing and Dewar, Thalen, 

 Huggins. 



24.— Caesium /3. X=4597. B,A. Report, 1884; de Bois- 

 baudran and Lockyer (4592). de Boisbaudran's value 

 was taken, rather to my regret. One of the first lines 

 got. Flame-spectrum. 

 25. — Caesium a. X=4555. Liveing and Dewar; B.A. Re- 

 port, 1884 ; Lockyer and de Boisbaudran (4560). 

 Flam e - spectrum . 



