Obviously, it's a Sterlingworth.
You may find this interesting.
http://www.foxcollectors.com/ah_fox/content/sterlingworth.html
Looks like a beauty.
That looks like a decent AH Fox Sterlingworth and may be an early pin gun, do you have a pic of the side of the receiver? Also a pic of the shotgun assembled showing the lever position when closed gives a good general idea of mechanical condition.
I would be happy to look it over for you if you wanted to meet me at the AGC, I know a thing or 2 on vintage guns.
Augie, I believe here's some kind of law of physics that says ya cannot have two side by sides (that nice) ...side by side. Seems you need to break that pair up. As a natural born giver, I'm willing to give whichever one you decide to banish (in the name of physics and natural law) a great new home. I here for ya big fella. Just let me know...
PS. For the record...you sure got a nice pair there...
Nice. They gonna give it to you or are they going to sell it?
And I forgot, this is what I mean about a pin gun, they were actually the earliest Sterlingworth's, had a recessed hinge pin like a Parker.
http://www.foxcollectors.com/ah_fox/content/sterlingworth_3.html
The Sterlingworth is a very good vintage SxS. The mechanicals are basically the same as Fox's graded guns. Fox needed a less expensive gun to sell as even their lowest grade was more than the average man at the time could afford.
A.H. Fox did not want his name on a lower priced gun so it was named the Sterlingworth, still came off the production line at the Fox factory.
Good original 12 gauge's go for 700 to 1000, beat up one's are 200 to 300, 16's go for more and 20's bring top money.
Here is a pic of my 2 graded Fox's from the same era, an AE and a XE.
I was able to get the serial number today. 52xxx, looks like it was produced in 1910. My mother thinks her Grandfather purchased it originally. Apparently it was in the original case which disintegrated when it was picked up. My mom said the shotgun was in a cloth sleeve, sounded to me like a gun sock so I am hoping it was protected. The pictures of it seem to look pretty good for a hundred + year old gun. I'm pretty sure it hasn't been touched in at least 30 years maybe more.
It looks like it's going to be my Christmas present.
And after having that Smith look at it, if it's deemed sound....go shoot it and think about your grandfather and what he may have thought about you shooting it. (and I'll just bet he would smile!).