Brand: E. Wolff & Son
Made in: England
This Wolff's includes the Southern Office mark. I believe it is before Wolff's merged into the Royal Sovereigh Pencil Co. The lead is square and there is no Royal Sovereign mark on the reverse of this pencil.
E. Wolff & Son was founded in 1796 with a factory in Neasden, London. There were three separate factories at the time: Aurther Johnson, E. Wolff, and Royal Sovereign. Two closed and consolidated to The Royal Sovereign Co. which moved to Wales in 1947. This factory was later taken over and closed in 2009 by Staedtler of Germany.