xxvnj RESULTS CONTINUED. 395 



a carbon crucible. One gram of barium chlorate yields '4405 litre of 

 carbonic oxide and this acts as a shield for the finer molecules of 

 barium, preventing their oxidation. The chlorine contained in one 

 gram of barium chlorate is '0734 litre, and this is taken by the 

 impurities (lime and iron) in the carbon crucible. 



Lithium carbonate in an arc of 25 cells in the lime crucible re- 

 verses the red line only. On adding aluminium, the blue line 4604 

 (4603 Thalen) is also reversed, but the green line was only expanded 

 and not reversed. 1 



Using the chloride in the arc and passing in hydrogen, not only 

 the red and blue lines but also the orange and green lines were 

 reversed. 2 



Lithium carbonate in a carbon crucible using the arc of 30 cells, 

 reverses the blue, red, and orange lines on adding aluminium filings 

 and potassium carbonate. 3 



Sodium carbonate in an arc of 25 cells in a carbon crucible 

 reverses the D lines only. Using sodium chloride in a lime crucible 

 with the Siemens' arc and supplying it with hydrogen, the lines 

 5687, and 5681 were also reversed, the less refrangible one being 

 the more strongly reversed. 4 



Potassium carbonate in a lime crucible with an arc of 25 cells 

 reverses the two extreme red lines and the line 4044, which resolves 

 itself into two lines 4042 and 4045. 5 



On employing a Siemens' arc and passing in hydrogen, in addition 

 to these lines, the lines 5831, 5802, 5782, 6946, 6913, 5353, 5338, 

 5319, and 5112, are reversed; the lines 5095, and 5081 were not 

 reversed. 6 



Rubidium : charred rubidium tartrate alone in a carbon crucible, 

 gives, with an arc of 30 cells, the two violet lines reversed and the 

 more refrangible of the red lines, 7800. In the Siemens' arc in a 

 lime crucible, the introduction of hydrogen reverses all the above 

 lines, and the less refrangible red one with difficulty. 7 



Strontium tartrate charred and taken alone in a Siemens' arc in a 

 lime crucible, reverses the lines 4812, 4831, and 4873 (4872 Thalen). 



1 Proc. Roy. Soc. vol. xxviii. p. 357. 5 Ibid. p. 369. 



2 Ibid. p. 473. e 2bid. p. 473. 



3 Ibid. p. 369. 7 jbid. p. 369. 



4 Ibid. p. 473. 



