350 Messrs. Trowbridge and Sabine on Wave-lengths 



wave-lengths of metallic lines produced by burning metals in 

 the electric arc or by vaporization in the electric spark are to 

 one hundredth of a wave-length the same as those of the 

 corresponding lines in the sun. 



Results. 



In the following table we have adopted the same symbols 

 and letters to designate the character of the lines which the 

 committee of the British Association have employed. Column 

 1 refers to the intensity on a scale of 10. Column 2 gives 

 our measurements of the wave-lengths of the copper lines in the 

 ultra-violet, from wave-length 2369*9 to 1944*1. Column 3 

 contains the measurements of these lines by Hartley and 

 Adeney. Column 4 are the corrections to be applied to 

 Hartley and Adeney's results. Column 5 contains measure- 

 ments by Liveing and Dewar. Column 6, corrections to be 

 applied to their results. Column 7 gives the symbols adopted 

 by the committee of the British Association, which serve to 

 describe the character of the line : — 



1. 



2. 



Wave- 

 lengths of 

 copper lines. 

 Spark. 



3. 



Hartley 



4. 



5. 



Liveing and 



6. 



7. 



Intensity. 



and 

 Adeney. 



Corrections. 



Dewar 

 Arc. 



Corrections. 



Intensity. 

 B.A. 



9 



2369-9 



2370-1 



- -2 







9br 



1 



. 2368-8 



2368-7 

 2365-8 



+ *1 





... 



2sd 

 1 



4 



2356-7 



2357-2 



— -o 







5 sd 



3 



2355-2 



2355-0 



+ *2 





... 



2sd 



3 



2348-8 



2348-8 











2 sd 



1 



2346-2 



2346-2 











2sd 



3 



2336-3 



2336-6 

 2303-8 



- -3 





... 



3sd 



1 sd 



1 



2299-6 



2300-5 

 2297-5 



- -9 







1 sd 

 1 sd 



7 



2294-4 



22950 



- -6 



2294-1 



+ •3 



6sd 



1 



2293-9 



2294-6 



- -7 







3sd 



3 



2291-1 



2291-4 



- -3 





... 



3sd 



3 



2286-7 



2286-7 









... 



3sd 



2 



2278-4 



2279-6 



-1-2 







2sd 



6 



2276-3 



2277-0 



- -7 



22760 



+•3 



6sd 



2 



2265-5 



2265-8 



- -3 







2sd 



2 



2263-9 



2263-9 







2263-6 



4-3 



3nd 



2 



2263-2 



2263-2 











3nd 



2 



2255-1 



2257-7 



-1-6 







2sd 



2 



2249-0 



22500 



-1-0 







2sd 



7 



2247-0 



2248-2 



2247-7 



-1*2 



2246-6 



+•4 



9sd 

 3nd 



