As you probably know by now, I am a stickler for safety in underhammer designs and this one provides it well for its intended purpose. Unfortunately, many believe that pocket pistols don't need a half cock notch, but that, in my opinion, is courting disaster - not to mention a stable full of liability attorneys.
According to Terry, our friend down under, "Not much is known of it other than it was made by a gunmaker named Correvon in Switzerland in 1854. It is featured at the Military Museum at Morge.
"On studying it, it seems that the hammer is held off the percussion cap by the neat arrangement at the hammer/trigger joint so that when the hammer is released it goes forward a lot more towards the nipple. I think I have that right. A very tidy looking arrangement."
Yes, it would appear that the ring trigger is pulled through like a double action pistol. The trigger sear engages the hammer notch and as the trigger is pulled, it also pulls the hammer through its arc. At a point, the hammer simply falls off the sear to fire the cap. Then the hammer would have to be re-set back into engagement with the trigger for the next shot.
Now this is a design that deserves some careful consideration for other applications - like, perhaps, an underhammer shotgun. Makes perfect sense when you think about it.
Also, you may have noticed the knurling on the barrel... That's right, it's a screw barrel. For those of you not familiar with this design, the barrel simply screws off the barrel stub. Then ball and powder are loaded into the "chamber." Then the barrel is screwed tightly back into place, and after capping, you're ready for action.
Thanks, Terry, for sharing the Correvon.
I like it!