Engraved by J. McArdell, 1746/65, as the work of Knapton. The sitter is identified in an inscription by Horace Walpole on his own copy of the McArdell as an engraving, which states that she was the wife of 'Capt Grieg of the Marines'. Her identity is otherwise obscure. The costume suggests a date in the late 1740s.