The archives of the Oregon Historical Society Research Library in Portland house many treasures—but only one honest-to-goodness treasure map. “It is an odd thing,” says research services manager Scott Daniels of manuscript number 2039, a scrap of creased and stained tracing cloth kept in the library’s climate-controlled vault. Unfolded, the document is 6 inches tall and 18 inches wide, covered from edge to edge on one side with long strings of blunt capital letters written in blue pencil, and a crude map sketched in blue and yellow. On the far…
