Could the name actually be. 'Bown & Tetley'? They were gun makers in Pittsburgh in the mid 1800s. They also made locks and various parts for the trade. If this is not the case, I do not recognize the other name you have reported. The barrel appears to be English as does the brass furniture. Hard to tell from here, but it may have been a flintlock. Not unlikely that the whole gun is a British made fowler imported and jobbed by B & T. Needs a little sprucing up but it's a fine piece and a round of applause to you for letting us have a look at it.
Dick
