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THE ROYAL SOCIETY OF CANADA 



In all experiments care was taken to see that the lamp was in the 

 steady state before measurements were made on the intensity of the 

 radiation. 



The form of spectrometer used was one designed and constructed 

 by the Adam Hilger Co. It is shown in Fig. 2 and in diagram in 



Fig. 2. 



Fig. 3. The energy measurements were made with a senstitive 

 Rubens thermopile shown in Fig. 4 in conjunction with a very delicate 

 Paschen galvanometer made by the Cambridge Scientific Instrument 



