Group photograph of U.S. Department of Agriculture personnel at an unidentified facility. The individuals in the photograph are identified as follows:

Standing (left to right): Mr. Whittaker; Louise Gardner; J. R.…

Exterior view of an unidentified United States Department of Agriculture building. The building is believed to be part of the U.S.D.A.'s Agricultural Engineering Laboratory facility located in Beltsville, Maryland.

Two exterior views of unidentified facilities believed to be associated with the U.S. Department of Agriculture.

Exterior view of the U.S.D.A.'s Agricultural Engineering Laboratory located in Beltsville, Maryland. The laboratory was predominately used for practical investigations related to plants and fertilizers in support of the…

General view of an International Fertilizer Distributor (No. 49 Machine) in use at the U.S. Department of Agriculture's Plant Industry Station facility in Beltsville, Maryland. This machine was used to determine the…

Photograph of mathematical physicist and physical chemist Richard C. (Chace) Tolman seated in front of a global map. This photograph is believed to have been taken when Tolman was serving as a scientific advisor to…

General view of an unidentified apparatus, possibly a hopper or type of granulation equipment, at an unidentified U.S. Department of Agriculture facility, likely the U.S.D.A.'s Agricultural Engineering Laboratory. Three…

General view of an unidentified apparatus at an unidentified U.S. Department of Agriculture facility.

General view of an unidentified apparatus at a U.S. Department of Agriculture facility. A radioactive materials sign and protective glass panel are visible to the right of the apparatus. The U.S.D.A. commonly used…

General view of an unidentified chemist handling radioactive material at an unidentified U.S. Department of Agriculture facility. The U.S.D.A. commonly used radioactive material for a variety of research and testing,…

Component parts, likely of a drillability apparatus, used at an unidentified U.S. Department of Agriculture facility.

General view of fertilizer trays on a suspension apparatus at an unidentified U.S. Department of Agriculture facility.

View of chemist William A. Jackson using a Gieger counter to examine a package at an unidentified U.S. Department of Agriculture facility. The U.S.D.A. commonly used radioactive material for a variety of research and…

View of chemist George Wieczorek (right) using a Geiger counter to measure ionizing radiation in an unknown substance, likely soil or fertilizer, at an unidentified U.S. Department of Agriculture facility.

View of chemist George Wieczorek (right) and an unidentified chemist using a Geiger counter to measure ionizing radiation in an unknown substance at a U.S. Department of Agriculture facility. The U.S.D.A. commonly used…

General view of chemist George Wieczorek (left) and an unidentified chemist using a Geiger counter to measure ionizing radiation in radioisotopes at an unidentified U.S. Department of Agriculture facility. A box of…

Close-up view of the interior of an apparatus likely used for the manufacture and/or testing of fertilizer at an unidentified U.S. Department of Agriculture facility.

View of chemist George Wieczorek removing a vessel from a Pereco kiln at an unidentified U.S. Department of Agriculture facility.

Portrait of agricultural economist Gae Adamson Bennett (b. 1917). While working for the United States Department of Agriculture Economic Research Service, Bennett co-authored numerous volumes on agricultural production…

General view of assorted containers and components used to house radioactive materials. The jar labels include space to record the isotope, amount, and date. These containers are believed to have been used as part of…

Close-up view of the handling of radioactive material at an U.S. Department of Agriculture facility. The U.S.D.A. commonly used radioactive material for a variety of research and testing, including the study of…

General view of a chemist handling radioactive material at an unidentified U.S. Department of Agriculture facility. The U.S.D.A. commonly used radioactive material for a variety of research and testing, including the…

George Wieczorek (right) and two unidentified chemists handling radioactive material at an U.S. Department of Agriculture facility. The U.S.D.A. commonly used radioactive material for a variety of research and testing,…

General view of a Stokes Tablet Press at the U.S. Department of Agriculture's Agricultural Engineering Laboratory facility. A tablet press is a mechanical device that compresses granulated material into tablets or…

Two views of a chemist inserting radioactive materials into an apparatus at an unidentified U.S. Department of Agriculture facility. The U.S.D.A. commonly used radioactive material for a variety of research and testing,…