There were two paradox barrels made for a "De Panw" in 1894 by Holland, so the barrel at auction was pobably one of them. There is only one barrel that has surfaced, supposedly, and it is barrel no.15184. In the Paradox book they say that the gentleman who ordered them likely got the idea from the rifled Spencers with an extra barrel for shot offered by Holland in their 1887 catalog.