(435) 



Assuming tor a hioiikmiI lluil the A'^ was also variable for the 

 ditferent series, 1 lia\'(^ calculated the constants A, a and A^,, from three 

 of the best observed cui-xes. For iY„ the following values were found : 



Principal Series 



1^' associated series 



Second 



Lithium 



Natrium 



Potassium 



Rubidium 



Caesium 



Hydrogen 



Helium 



Natrium 



Potassium 



Silver 



Magnesium 



Zinc 



Oxygen 



Natrium 



Magnesium 



Calcium 



Zinc 



Aluminium 



109996 

 107178 

 105638 

 104723 

 104665 

 109704 

 109703 

 110262 

 109081 

 107162 

 108695 

 107489 

 110660 

 107819 

 105247 

 103702 

 105399 

 105721 



These values ha\'e been calculated from wa\e frequencies not 

 corrected to vacuo. 



x\s appears fi'om these values JSf^ is not absolutely constant. As 

 Kayser ') found in another way, we see, however, that relatively 



1) Kayser, Haiullxicli II. p. ."iS^. 



