Am feeling grateful to have picked up this OB spool from Jeff Kaminski's collection last night. I've heard it is ca. 1906-1907 and we suspect there are three (possibly four) that were recovered from one substation in either Washington or Oregon at least 25 years ago. This measures 12" tall and 11" in diameter and is made in at least two pieces.
If anyone can fill in this history of this piece, it'd be greatly appreciated.