David,
I believe that this particular style of foot is uncommonly found in positively attributable British glass of this type, and that it usually indicates a Bohemian or other mainland European origin in such glass found in Britain. A British attribution cannot be completely excluded. The shape is not usually associated with American glass.
I find it impossible to believe that any professional glassmaker or apprentice at one of the top British glassworks such as Stevens & Williams, John Walsh Walsh, or Whitefriars would have left the foot in this way to be finished by grinding.
Bernard C.
