Unfortunately the subject is unidentified. Presumably Turner drew this man from life when visiting the Victory and intended to include him in his Battle of Trafalgar, as Seen from the Mizen Starboard Shrouds of the Victory (Tate N00480;1 see Introduction to the sketchbook for the picture and related works). He may be one of the men described on folio 12 (D05462; Turner Bequest LXXXIX 14), since that leaf was known to Finberg as folio 14 and the present one as folio 16 – tantalisingly close. For a similar portrait sketch, see folio 27 (D05470; Turner Bequest LXXXIX 20).
Martin Butlin and Evelyn Joll, The Paintings of J.M.W. Turner, revised ed., New Haven and London 1984, p.46 no.58 (pl.68).