Originally Posted by Hugh Lomas
My concern is that there are no UK proof marks at all.

Not just no UK ones, no marks at all. Just "ISH" and "STUBS TWIST".

Originally Posted by Hugh Lomas
The word LONDON on the rib was somewhat duplicitous in as much as it could describe a type of twist steel but also imply to the unwary that the gun was made in London. Many examples end up in the colonies in one guise or another.

Cutler's name on the locks indicates that he was taking a degree of responsibility for his guns, and possibly also some pride in them. At the same time, he doesn't appear to have enjoyed the kind of name-recognition that led to numerous "Richard" or "Purdy"-style forgeries.