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



Ca. From Vl + Vat g= 6, dv = *1, W = 40'124*005, q = 361'56 + '60. 



The denominator of D 13 (2) = 691 A 2 gives q = 361*84 '1. 



From the discussion of CaF, q = 361*77 *2. 



Mantissa difference of CaD (2) and CaD (3) = 99A 2 = 133542 + 10028, 

 q = 361*870 + 1*76, the great uncertainty being due to g. 



The most reliable appears to be that from D 13 (2), and is included in the others. 

 Value adopted, 361*84*1. 



Sr. From Vl + v a> g = 10, dv = *2, W = 87*66*03, q = 361'63-56. 



The denominator of D 13 (2) does not appear as a multiple of A 2 , whereas that of 

 D 12 = 178A 2 . If this is a real relation, q = 361735 + '33. 



From the F collaterals and the denominator of F (2), q cannot be far from 361 '77 + *2. 

 Adopted value, 361 77 '2. 



Ba. From v 1 + v 2 , with g = 32, as modified in Table II., and +5 allowed, dv = '2 

 and W = 137'43*06, q = 362'07'53. 



From the D 13 (2) collateral = 69A 2 , q = 361'968'3 



From D 13 (2), as found from the F series, q = 361'856*36. 



From the F discussion, q = 361*971 *39. 



The most reliable is probably the mean of those depending on D 13 . Adopted 

 value, 361*913 '4. 



Ka. From Vl + v 2 , g = 1, dv = '2, W = 226*4 + '02, q = 361'846 + '66. 



From the F discussion, q = 361'94 + 'll, but as there is some uncertainty in the 

 F theory, the limits of error should be greater. Adopted value, 36 1*94 + '33.* 



Zn. From VI + VK with g = 3, dv = 0, W = 64'40'03, q = 362'238 + '36. 



From Dj 3 (2), q = 361*682*47, and from the F values lying between, 362'15 and 

 361*87. Value adopted, 362*01 '25. 



Cd. From Vl + v a , with g = 2, dv = '1, W = 112'3 + *1, q = 362'36*66. 



In the D 13 (2) theory Cd appears to occupy a similar position to that of Sr in the 

 other sub-group, in that the multiple of A is carried back to D n or D 12 . The most 

 accurate is that from i/!+'(/ 2 . Adopted value, 362'36'66. 



Eu. From Vl + Va , with g = 10, dv = 4, W = 151'93'03, q = 361*94'8. 



From D 13 (2), q = 361*441. Adopted value, 361'94'8. 



Hg. From v 1 + v 2 . There is some uncertainty as to the ratio of A 2 : A t . A 2 = 41$, 

 best agrees with the transference value from A x to A 2 discussed at the commencement, 

 and it gives a value of A 2 = 29725'65 which is in close agreement with the value 

 found in the F discussion, viz., 297 82 -127 '2g. 



* HONIGSCHMID ('Sitz. d. k. Akad. Wiss. Wien,' November, 1912) has recently made a careful 

 determination of W, and gives 225-97 in place of 226-4. This would make the oun 363- llw 2 a value 

 quite inadmissible if the spectroscopic data are reliable. Although they are not good, they can hardly be 

 so uncertain as this value of q would indicate. For what it may be worth, the spectroscopic data would 

 seem, therefore, to weigh against the acceptance of the new atomic weight. 



