The sitter holds an anatomical drawing and this has suggested an identification with the physician-poet Sir Richard Blackmore (d.1729), to whom he bears some resemblance (cf. John Closterman, cat. exh. National Portrait Gallery, 1981, no.13). There is also perhaps some resemblance to the physician Sir Edmund King (1629-1709). His pose matches that of Kneller's 1690 portrait of the shipbuilder Sir Anthony Deane holding a drawing of a ship (National Portrait Gallery).
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