Admiral Adam Duncan, 1st Viscount Duncan, Tassie Bas-Relief Portrait Profile Plaque, Circa 1797.Admiral Adam Duncan, 1st Viscount Duncan, James Tassie Bas Relief Portrait Profile Plaque Dated 1797, Signed Tassie F. A Tassie Bas Relief White Glass Paste Portrait Profile Plaque Dated 1797, Signed Tassie F. The oval frame with brown velvet backing and gilt wood. The exterior with faded gilt wood. Brown paper backing to the reverse and a suspension loop. Admiral Adam Duncan, 1st Viscount Duncan (1731 1804) was a Scottish naval officer. Best known