I have no idea who's signature that is, but you've taken a nice picture of it and someone will know. There's a group called the engravers guild. I have no idea how to contact them, but with that photo you should be able to find the workman.
Well, I don't know, but it looks good, and they were smart enough not to engrave the back of the cylinder, where the turn line is, so one can use the revolver without screwing up part of the engraving.
I have contacted the Firearms Engravers Guild of America a couple of times for info about engravers from the past (1950's and 1960's). They were no help at all. Their information is more on current engravers than some of those from the past.
Do contact them but don't be surprised if they can't help you.
And as the previous poster noted, there are a lot of (very good) engravers that don't belong to the guild.