jayzbird,
Welcome.
Bayard was a trade name for Pieper, one of the largest of the Belgian gun makers. Henri Pieper, whose father was German, started the firm in 1859. About the time guns like yours were 1st made his son Nicolas Pieper had taken over. The patent date refers to the barrels. This gun would have been a Modified Diana. Bayard was a mythical horse or knight depending on which myth you follow.
I prefer the horse myth myself.
Does it have external hammers? If can post some pictures of the barrel flats and the receiver markings, it may be possible to tell exactly what year the gun was made.
Pete
