Magnetic Separations of the Lines of Iron, Nickel and Zinc in Different Fields. J 



iron (completely free -from nickel) spark was 

 photographed and the spectra compared to dis- 

 tinguish the line due to these metals. 



4. Arrangement. The room in which the 



experiment was undertaken was on a concrete 



hasement. The iron rails on wdiich the rod 



supporting grating and the photographic camera 



were placed were fixed on stone piers. This 



~^"' ■ firm setting enabled an expcsure of many hours 



duration to be undertaken without any risk from external shocks. 



The temperature did not vary so much as to disturb the sharpness 



of the lines. The arrangement is show^i in Fig. 5. 



OvicaveLmJ jy^^ß^ 



A/nmefer 



InducéCon ooti 



CapariLy 



S'eoonJQry _^, Ammefc.7- „ ^ , 



^aitery /^^ Hcec-tronti 



Fig. 5. 



5. Photography. Many kinds of photographic dry plates 

 were tested to find whicli would be the best for my purpose. 

 Those tested were (1) Lion 20, (2) Lion 225, (3) Lion, Ortho- 

 chrome Plates, non-filter, (4) ditto, backed, (5) Paget Prize Plate, 



