188 



THE ROYAL SOCIETY OF CANADA 



could be assigned to the various lines with an accuracy of probably 

 ±0-01)U. 



IV. Observations. 



After the apparatus was carefully set up and found to be in good 

 working order a set of readings was taken on the energy spectrum of 

 an Arons^ amalgam lamp. The amalgam in this lamp consisted of 

 about 60% Hg, 20% Pb, 20% Bi, |% Zn and |% Cd., the lamp was 

 run on the 110 volt direct current circuit with a suitable resistance in 

 series. The energy curve is shown in Fig. 7. Thirty-six distinct 



*Ï0 .60 .00 Iflo 



i60 280 loo 



WAVt LttIGTM in^ 



Fig. 7. 



maxima were observed in all between wave-lengths 0-70/x and S-O/j.. 

 Possibly as many more could have been distinguished by repeated 

 observations; but as there was no way of distinguishing which were 

 mercury lines and which were lines of the other metals further work 

 with this lamp was abandoned. 



Readings were then taken, as stated above, with a lamp contain- 

 ing only pure mercury. The maxima from a large number of sets of 

 readings were compared and the regions which contained constantly 

 recurring maxima were carefully examined so as to establish the exact 



lArons, Ann. d. Phys. Band 23, 1906. 



