Smithsonian Report, 1 91 5.— Rutherford. 



Plate 5. 



1. Track OF Alpha Particles 

 Showing Sharp Deviations 

 (Wilson). 



2. X-Ray Spectra of Successive Elements 

 (Moseley). The Additional Lines in Spec- 

 trum of Co and Ni are Due to Impurity. 

 Brass Shows the Combined Spectra of 

 Copper and Zinc. 



