Prof. Owens on Thorium Radiation. 



Table VI. 



Thorium Nitrate. Thick layer. 



Screening effect of thin Aluminium foil. 



Plates 5 cm. apart. Lower plate 95 volts 4- , 



375 



Layers of foil. 



Time of 100 div. in sec. 



Current. 







62-4 



100-0 



1 



107-4 



58-0 



2 



183-2 



340 



3 



264-6 



22-0 



4 



429-0 



14-5 



5 



6420 



9-7 



6 



899-0 



7-0 



8 



1220-0 



50 



12 



11930 



4-1 



Fig. 7. — Screening effect of thin Aluminium foil. 

 Thorium Nitrate. Thick layer. 



5 6 7 



Layers of foil. 



