296 



Prof. Richardson and Lieut. Bazzoni on the 



curve of fig. 5 which is obviously difficult to analyse into its 

 constituent curves. We do not attempt to make any such 

 analysis in this paper. It is, however, clear that the curve 

 furnishes a direct indication of the maximum frequency 

 occurring in the spectrum. 



Fig. 5. 



no 



160 



150 



140 



330 



120 



HO 



100 



90 



80 



70 



60 



50 



40 



30 



20 



10 



5 \0 85 20 25 30 



«- Volts 



Specimens of the results obtained when the apparatus was 

 filled with pure helium are shown in fig. 6, which gives the 

 negative electrometer deflexion as a function of the field. 

 The figure also gives the frequencies corresponding to the 

 inside radius for each setting and the related wave-lengths. 



.urn i i i i i j ii in. i -i W L i i -uor i 



