Nice find. I've looked in pawn shops, flea markets, and antique shops for years and years, and I've never stumbled across one unexpectedly... and I live in Indiana where a lot of them were made, so I'm a little jealous! If you look at the horses' heads, they are rather cartoonish, and the riders' hands are not well defined, details of Timothy Tansel's work. The eagle's larger talons and the "smooth" style wings, i.e., no sharp angle on inside edge separating the lower and upper sections of the wing, help date the horn as a slightly earlier example of Timothy's work... about 1838-1839.
One odd detail is his "incomplete" fish-mouth border on the spout end, where he put the large scallop border on the front side of the horn that shows, but not on the back side... and even on the front side, he didn't fill in the small interior scallops with closely spaced hash marks like he did on the basal border. That, plus the apparent lack of polychroming, seems to indicate he was in a bit of a hurry to complete this horn.
If you want to learn more about Tansel horns, check out the blog articles at
www.kentuckygunmakers.com. I've got a large collection of Tansels, but each new one is fun to see... one more small piece of the puzzle.
Would you mind posting the inside curve and outside curve dimensions, from tip of spout to where horn body meets plug?
Shelby Gallien