Light 



Absorption and Ft 



uorescence. 







Table YIII. 











F = 0-95. 







Ri/Li 



= 0, 



LiOi=7-B6. 



io- 



" s C.G.S. 



a 2 /L 2 . 





n 

 from Tables. 



fr 



n 

 ova formula (8). 



500 





243320 





Imaginary 



1000 





1956-50 





Imaginary 



1500 





516-67 





Imaginary 



2000 





214-35 





Imaginary 



2500 





421-14 





367-82 



3000 





481-66 





45332 



4000 





527-65 





514-16 



5000 





546-68 





-538-32 



6000 





555'54 





550-19 



5G5 



resistance is varied by means of a rheostat across the 

 secondary terminals and the secondary capacity is not a 

 negligible quantity, the system will possess two oscillations 

 if the resistance of the rheostat is greater than a certain 

 value. 



The Physical Laboratory, 



University College of North Wales, 

 Bangor. 



LIV. Light Absorption and Fluorescence . — V. The so-called 

 Molecular Rotational Frequencies of Water. By E. C. 

 C: Baly, C.B.E., M.Sc, F.R.S.\ Grant Professor of 

 Inorganic Chemistry in the University of Liverpool*. 



IN a recent paper t the absorption system of sulphur 

 dioxide was discussed, and it was shown that the whole 

 of the absorption-bands shown by this gas can be expressed 

 in terms of three fundamental frequencies : 2*4531 X 10 11 , 

 8*19 x 10 11 , and 1*296 x 10 12 . It was also shown that the 

 frequency 2*4531 X 10 11 is characteristic of the atom of 

 oxygen, and that the two frequencies 8*19 x 10 11 and 

 1*296 x 10 12 are characteristic of the atom of sulphur, since 

 the infra-red absorption-bands of oxygen can be expressed in 

 terms of the first and those of sulphur and hydrogen sulphide 

 can be expressed in terms of the last two constants. 



The combination of these three constants to give the 

 frequencies characteristic of sulphur dioxide would seem 



* Communicated by the Author. 



t E. C. O. Baly and C. S. Garrett, Phil. Mag. vol. xxxi. p. 512 (1910). 



