Thank you for the interesting input. Same inscription is engraved both on the rib and locks. It is small and faded but yesterday a visiting friend with younger eyes (and camera) confirmed the name. I should have asked him to take a few pictures but we were so taken by the enigmatic old gun that I forgot it, unfortunately. If nothing else it's not a bad feeling to own the World's only known gun by an ancient London 'maker'. smile

Kind regards,
Jani