278 REPORT—1885. 
The Cadmium Spectrum. 
Wave-lengths 
Scale numbers 
1 percent. ‘| 0:1 percent. | 9-01 per cent. | 0-001 per cent. 
Hundredths of an inch 
79°37 3612-0 3612°0 3612:0 
79°68 3609°6 3609°6 3609°6 
94°30 3466°7 3466°7 3466°7 
94°50 3465°2 3465°2 3465°2 
101-45 3402°8 3402°8 
119:0 3260°2 
205°87 27477 2747-7 
248-24 2572°3 2572°3 
326°8 2321°6 
329°85 ; 2313'5 2313°5 2313°5 
339°25 ) 2288°8 2288°8 2288°8 
348°15 | 29658 2265°8 2265°8 2265°8 
377:48 21964 
400-2 2146°8 
The Aluminium Spectrum. 
Wave-lengths 
Scale numbers gpa 
1 per cent. O-1 per cent. | 6°01 per cent. | 0°001 per cent. 
Hundredths of an inch 
49°85 J 3960°9 3960°9 3960°9 39609? 
51:16 3943-4 3943-4 3943°4 3943°4? 
The air-lines contiguous to the above are very strong, hence it is a little doubtful 
whether they are present in the spectrum of a solution so dilute as 0:01 per cent. 
£ 70-02 3713-4 
U71°05 37015 
T7917 3612-4 3612-4 3612-4 
80°5 3601°1 36011 3601°1 
82:07 3584-4 
142 86 3091°8 3091°8 3091°8 3091°8 
144°5 3081°2 3081°2 30812 3081:2 
148°5 3056 6 
191°76 2815°3 2815°3 2815°3 28153 
226:3 2659°3 2659°3 
228°26 26512 2651-2 
249-66 2566'9 2566-9 
308-55 2373°3 
309:0 2372:0 
309°6 23702 
309-94 2367°2 
310°62 2364°5 
The line with wave-length 3584°4 is both much longer and stronger 
than either 3612°6 or 8601:2, yet it is not so persistent. From appear- 
ing as a strong line it disappears rather suddenly. 
The line with wave-length 2815:3 is the strongest in this spectrum. 
