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gap in the plating between 8 and 18 mils wide depending upon the point of 

 the stylus. Following the burning operation, the plate is immersed in a 

 photographic hypo solution to remove all traces of the burned residue after 



Fig. 13.5 — Tool for dividing plating (electric stylus). 



which it is carefully washed and rinsed in water and dried. In this process 

 it is important that the plates are not kept in the h^-po solution for longer 

 than two or three minutes, otherwise discoloration of the silver coating will 



