
Undated
IB
Illustrated London 1806 hallmark.
London
The source lists alternative attributions: James Beattie (1790), John Boyer (1794), Joseph Barnard (1798), John Blake (1803), John Bunn (1806), John Blades (1812 or 1827) and John Brent (1820). These dates are attribution clues, not a mark-use interval.