Below is a photo of the screwdriver arms of two Private�s wrenches. The upper arm is stamped with the initials �N & F.S�. The lower has the initials �B & S� and a Birmingham inspection marking on the top of the arm. I have yet to identify these two implement maker firms and/or individuals.  
 
English Gunmakers by De Witt Bailey and Douglas A. Nie has an entry on page 32 for the firm of �Brookes, Edward & Son, 1849 - 1874� noted as being Implement Makers in Birmingham. Perhaps the �B & S�?
 
Any information re these two makers would be very much appreciated.
 
Dave