Lot Essay
Johann-Julius Heinsius (1740-1812), peintre de Mesdames de France and author of the present self-portrait, has been confused with his brother Johann-Ernst (1731-1794, working for the courts of Weimar and Rudolstadt) until the publication of Hedwig Dauch-Schroeder's thesis Johann-Ernst Heinsius (Jena, 1937). pp. 7-11.