I)H. W. M. HICKS: A CRITICAL STUDY OF SPECTRAL SKRIKS. 



TABLE I. (continued). 



Data on which the Table is based. 



Na. The limit is 24476-11. It is the limit found in [I.] corrected by the result of ZiCKENDRAirr's 

 measurements of the high orders of NaS. The value of v adopted is that deduced from FAIIKY and 

 I'KHOT'S interferometer measurements of the D-lines using 9-figure logarithms. Consequently, the results 

 are more reliable than would otherwise bo expected from such a low atomic weight. But on this point, 

 see below (p. 331). 



The limit for K is 21964-44 corrected from the value in [I.] by addition of 1-06 as indicated by 

 ZICKKNDRAHT'S observations. The value of v is very ill-determined. A value of v = 57-73 would make 

 q = 361 80. SAUNDERS' results for S (3) give v = 57 75, and K.R.'s for S (4) give 57 60 30. The 

 value in the table is that used in [I.] 57'871. The limits for Rb and Cs are those given in [I.] for 

 S ( oo ), viz., 20869-73 and 19671-48. 



Cu. S ( oo ) = 31515-48. 



Ag. D ( oo ) = 30644 60, found from first three lines. FABRY and PKROT have measured by the 

 interferometer Dn (2) and DJI (2) and K.R.'s are extremely close to these. They have been taken as 

 correct to -001 A.U. The lines DU and Dn are so close that their difference of wave number as given 

 by KAYSER and RUNOK are prok-ibly of the same order of exactness. We may regard, therefore, 

 K. and R.'s DU - DU and F. and R.'s D^ - DH as quite exact up to the second decimal place. This gives 

 v 920 - 61. It cannot be uncertain to more than a few units in the first decimal. A more correct value 

 is obtained below (p. 404). 



The limits of the 2nd and 3rd groups of elements are those given in [II.]. In the cases of Zn, Cd, Hg, 

 the interferometer measurements of FABRY and PEROT are used, except v-t for Cd and Hg, with 9-figurc 

 logarithms in order to get an extra significant figure, their readings being reduced to ROWI.AMI'S si-.-ili- 

 by HAKTMANN'S factor 1-000034. In these cases the values of v may be taken as practically correct 

 to -001 A.U. 



For Sc, see Appendix I. 



VOL, COXIII. A. 2 U 



