Mike, thanks for that - very helpful. I've decided not to buy the particular rifle I've been considering. It is probably a trade boxlock set up by Fraser. It has the Fraser patent top lever but neither the graceful scalloped action nor the side screw you mention. Still a pretty rifle though.

Curl, I definitely do get your drift and I love your Farquharson. I think the lesson for me here is that I need to do a great deal more studying on double rifles.

Incidentally I've been reading "More Single Shot Rifles", written by James J. Grant in 1959. There is a full chapter on the Farquharson action, complete with a story of the patent battle. The book in general is a great read if you haven't seen it.

Thanks to all for the very good advice. I've avoided what might have been a mistake.