Quote Originally Posted by greenwayjames View Post
It was loosely based on an idea used in some cowboy type revolvers to get around having to load only 5 chambers in a six shooter.
That would be the 1896 Fryberg patent transfer bar safety, popularised by Iver Johnson in revolvers as the “hammer the hammer” [and it still won’t fire] safety, and used to this day on Ruger revolvers.

Sounds like Girandoni had the same idea a century earlier?