I know what you're thinking: "Did he fire twenty shots or only nineteen?" Well, to tell you the truth, in all this excitement, I've kinda lost track myself.
I can't figure out how this works. That thingy on the top seems like some sort of flintlock attachment point, but do you hold your hand on top, directly over the flame from the pan?
I also don't see any powder pans, and this predates caps. Naples had paper cartridges, so I assume it used those, but a contraption that turns upside down needs a really good sealing powder pan to work.
Do you turn this by hand? I assume so, though that middle has a lot of space for a mechanism.