Group photograph of personnel at the Fixed Nitrogen Research Laboratory's experimental blast furnace plant, taken at the conclusion of a Tennessee Valley Authority (T.V.A.) operation. Per notations accompanying the photograph, the individuals are identified as follows: (back row, standing): Hopkins; Tuve; Clark; Allan; Royster; Hignett; Reilly; Wright; and unidentified; (front row, kneeling): Bowe; Jansen; Rigsby; Connors; unidentified; Damico; and Finch.

The Fixed Nitrogen Research Laboratory (F.N.R.L.) was established at American University in 1919 under the directorship of Arthur B. Lamb. Initially part of the War Department, the F.N.R.L. was the successor to several wartime initiatives to develop a secure domestic supply of nitrate compounds necessary for the manufacture of explosives during World War I. With a staff of about 110 individuals, including 35 to 50 chemists, the F.N.R.L. focused on the manufacture, production, and development of products of atmospheric nitrogen, including munitions and fertilizers.