Been working on my lathe making pullmax & bead roller dies, in the bottom of the misc box is this Scholler wrench. Quick internet search says it was only made a few years 1916-18, guess it would be good with the Barnes treadle lathe.
If it is not too worn it might be a "user" -- the odd thing about SCHOLLER & a couple of others (some RED DEVIL & stamped house brands ) is that the base of the adjustable jaw is roughly square in cross section rather than oval, slotted oval or round.