Alexander Wetmore, Sixth SI Secretary, by Unknown, 1944, Smithsonian Archives - History Div, Alexander Wetmore, ornithologist and sixth Secretary of the Smithsonian Institution from 1944 to 1952. This is a portrait photograph of Wetmore taken on April 10, 1944; bust, looking to his right. The writing on the back of this photograph states that Wetmore was the President of the Explorer's Club..