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ROYAL SOCIETY OF CANADA 



figure 6. The second complementaries were red {X = .656 /x) and 

 green {X = .492 fi), determined by Helmholtz. The data in this case 

 are giveai in table 5, and plotted in figure 7, with the same normal tas 

 the preceding curve. 



Fig. 5. 

 TABLE 4. 



