Stecker

[GIO]

I often asked myself when and by whom the stecker has been invented.
Same question with the so called "butterfly"(the little swinging appendix on the lower part of the cock, made to fasten the release of the same when firing).
This device is found on flint and percussion locks I think it has not used later.
I believe some friend can satisfy my curiosity.
Thanks in advance.
Gio