Originally Posted by rhmc24
Here's the skinny - as someone touched on above. It is to allow the pan to be primed while the frizzen is open and the hammer down. Most flint locks when primed and 'ready' must have the hammer at half cock to carry it safely. For long storage some people think that constant strain on springs is undesirable. So - this device allows the gun to be primed for quick use, with the hammer down, frizzen open and springs relaxed. It is a rare feature, second one I know of.
French, I agree.
Ok that's wonderful information. So we know now what the use is for and you guys are pretty sure it's French, we're getting there. I'm excited! I'll still post the marking on Sunday and maybe we can get it narrowed down some more. My Dad is mulling a $1500 offer for the gun so I'll tell him to hold off. Looks like he might have a goodie.