238 
PROF. A. FOWLER ON SERIES LINES IN SPARK SPECTRA. 
pi Tp / \ _ 82,044 8 
Ca : F (m) - 82>105 . 6 
Sr : F (m) — 
444,561 
(?n + 0‘00586) 2 
455,0551 
74,236-6 
74,516-3 J (m + 0‘025265) 2 
Thus, when Lorenser’s formula is used throughout the discrepancies are 
Ca: 82,044-8-81,820-0 = 224-8 
Sr: 74,236-6-73,833-5 = 403-1 
The Hicks 4N formula gives the variable parts of the expressions for the first D 
lines and their satellites as 
Ca: 70,289-2 + 11,703-0 = 81,992-2 
70,289-2 + 11,763-8 = 82,053‘0 
Sr: 64,323-3+ 9,679*5 = 74,002-8 
64,323-3+ 9,959-2 = 74,282-5 
Comparing these values with the limits calculated from the observed F lines by 
means of the formula with 4N, we have the discrepancies reduced to 
Ca: 81,992-2-81,949 = 43'2 
Sr : 74,002-8-73,968-3 = 34’5 
The discussion of the available data for calcium and strontium, therefore, leads to 
the conclusion that series consisting of enhanced lines may be represented by the 
formula of Hicks if the ordinary numerator N be replaced by 4N. It is, of course, to 
be understood that the formula is subject to the same limitations as the one 
involving N as applied to ordinary series. 
There is, however, one important difference between the enhanced line series of Ca, 
Sr, and Ba, and the ordinary arc series of these and other elements, namely, that in 
the case of enhanced lines the first observed member of the Diffuse series appears 
with a negative sign, while in the corresponding ordinary series it has a positive sign. 
In each case the lhnit of the F series and the separation of the doublets are nevertheless 
derived from this first member taken with proper sign. This is the “ new relation ” 
discovered by Saunders in connection with the wide and narrow doublets of Ca, Sr, 
and Ba, namely, “The convergence wave-number of the complex pair series (D) plus 
the wave-number of the first term equals the convergence wave-number of the narrow 
pair series (F).” 
The modified Hicks formula may accordingly be employed with confidence in 
searching for possible relationships of the “ 4481 ” series with other series of enhanced 
lines of magnesium. 
