I'm sure PeteM will weigh in on this but Bayard was a brand name owned by the various corporate entities that began with Henri Pieper. I believe Bayard was the street his enterprise was located on.
Pieper was a pioneer in the large scale production of firearms, was a founding partner in FN and owned a large damascus barrel manufacturing facility. He had a successful patent on mono-block barrels, designed to speed the production process by simplifying the alignment and assembly of the two barrels.
I'll dig out some more information tonight but most of what I know has come via PeteM.
I have four Pieper guns myself. An early sidelock with the monoblock Damscus barrels and 3 boxlocks from later years, all with the same, unique locking mechanism. When the top lever is pushed right, it pulls a rib extension back from its slot between the barrels. When the action is closed it is a seamless (almost) rib from the barrels back to the top lever. Probably not explaining that well. In the picture you can see the seam between the top rib and the rib extension just forward of the breech face.
