Help ID'g antique weapon

[herlockscholmes]

I was helping my parents move out of their house last weekend and came across four antique weapons in the attic. The one displayed below is interesting - I'm toldthat it was a musket used in the ACW, but I suspect this may have been one of the tall tales that the guys around the gun club my dad grew up on told each other. I'm curious what it is. Posted to Reddit and they recommended sharing here. The few markings I could find were pretty worn down, but I added photos here in case the partials could be identified.

[Longknife]

I assume you are asking about the single barrel one on the bottom. It appears to be a fowling piece or "shotgun' of English origin or made in America from imported English parts. The brass scroll guard with squared rifle style cheek piece is unusual. It looks like the lock is  one of the commercial locks that were widely available, in the 19th century and its poor fit suggest that it is not original to the piece. It could have been originally made as a flintlock. We need many more pictures in better light to try to ID this one.... LK