The attribution to Ozias Humphry rests on the evidence of an engraving of this portrait by Walker, 1785, with attribution "Humphreys pinx.t" (Wellcome Collection 996i). Humphry was originally a miniature painter. However, "During the period 1777 to 1785 Humphry attempted to concentrate on oil painting, but without the success that he had enjoyed as a miniaturist before his trip to Italy. He failed to translate the qualities that lent such distinction to his miniatures—elegant and inventive compositions, rich colouring, and a grandeur in the presentation of his sitters reminiscent of Reynolds—to the medium of oil" (Oxford dictionary of national biography)
