DR. W. M. HICKS: A CRITICAL STUDY OF SPECTRAL SERIES. 



427 



2. 



3. 



calculated frequencies for m > 2. These for m = 3, 4, 6 are 22277'28, 25148*60, 

 27569'40. The last gives d\ = '40. No lines correspond to the others, but 22211 

 observed by C. and K. with Cu electrodes and (15) 25107'14 (R), (9)...6'64 (W.) are 

 respectively 66'28 and 41'56, (41'96) less. Now a ^ displacement on the limit gives 

 13'96, so that these correspond within error limits to a (5^ 1 )F(c) ) d\ = '5, and 

 (3^)F(oo), d\ = '06, and stand in some analogy to what has been seen to happen 

 in X. The intensity of the second line however would seem very great for m = 4. In 

 support of the C.E. line with its large possible error is (2)22196'92 (ROYD) at 13'08 

 behind it or an extra $ It would make 22196 = (6^) F, and consequently F = 22280'68, 

 i.e., dX = 7. If the 5640 lines exist, they all lie outside the region of observation 

 except in the case of the first line 15846 where the corresponding triplet set is found 

 (see above). However, anticipating the value of the links obtained later and using 

 them as sounders, viz., e = 23678'3, u = 1119T8, v 13680'6 with some uncertainties 

 we can test for their existence. Taking the observed lines 22196'92, 22211 we expect 

 lines about 27838, 27858, only to be observed if strong. There are none, but there 

 are (3) 14166 (W.) 2816 16982'0 (C.E.) which with the v link give 27846'6l'9-f dv, 

 30662-6 3 + dy, separation = 28165. These suggest the triplet set (^) F, viz., 



22196'9 5649-7 

 22210-9 5635 + l'9p + du 



27846-6 + V 



2816 + 3p'-l'9p 



The results of sounding are indicated in the following, where, since e, u, v are only 

 approximately known, their values are supposed corrected by de, du, dv. The letters 

 after wave-lengths refer to observers : 



Outside 

 22196-9 

 22210-9 



5649-7 



5635 + 1 9p + dv 



m-3. 



(3) 14166 (W.).w 



27846-6 + l- 



F. 



2816 + 3p' - 1 9p 



16982 (C.R.).w 

 30662-6 + 3p + dv 



With the calculated value of Fj the first separation is 3 "5 larger. The first line is 

 S^ displacement on 22210. If the former does not belong to the system, we may take 

 C.R.'s direct line which has possible error of 4 or 5. 



Outside 

 25107-14 



'v.(O) 15136 (W.).e 



(25134-3) 

 [25148-60] 



m = 4. (3^) F. 

 (28!) 19583 (C.R.).w 



5640-6+4p + du 



5648-31+de-dv 

 5648 



(28,) 22398 (C.R.).w 

 2814-2 + 5p'-4p (33562) + 5p + du 



v.(0) 20784- 31 (W.).e 

 .(- S x ) (1) 20799 (C.R.). 

 (30782-6) 



.(!) 20799. 



2814-9 

 2816-0 



.(0) 23598'2(W.).e 



(33596-5) 

 w.(l)21126-0.e 



