Alexander Wetmore on Sierra San Xavier in Argentina in 1921, by Unknown, April 17, 1921, Smithsonian Archives - History Div, Alexander Wetmore sitting on the ground in a field on Sierra San Xavier, at 7,500 foot elevation above Tafi Viejo at Tucuman, Argentina on April 17, 1921. He is holding a knife in his right hand and a rifle is lying in his lap. Wetmore was working for the Bureau of Biological Survey on this trip. Wetmore, noted ornithologist and sixth Secretary of the Smithsonian Institution from 1944-1952, conducted extensive fieldwork throughout the islands of the Caribbean and various Latin American countries..