According to a report of the Paris Exhibition of 1867, one of the pieces being exhibited by Johnson and Matthey "has been used in a Withworth gun for more than 3000 rounds, and scarcely shows signs of wear yet.
Theo một báo cáo về Triễn lãm Paris năm 1867, một trong những mảnh này được Johnson and Matthey trưng bày "has been used in a Withworth gun for more than 3000 rounds, and scarcely shows signs of wear yet.