General view of employees at work in the Bureau of Chemistry's Protein Investigation Laboratory, with view of assorted laboratory glassware and apparatus. Part of the U.S. Department of Agriculture, the Protein Investigation Laboratory investigated nutrient deficiencies in protein foods in order to determine a ratio whereby normal growth could best be promoted.

The Bureau of Chemistry was established in 1901 through Congressional appropriations as a successor to the U.S.D.A. Division of Chemistry and significantly built upon the work of its predecessor, which researched the adulteration and misbranding of food and drugs on the American market. The 1906 Food and Drug Act notably increased the Bureau’s regulatory powers and led to the establishment of laboratories for testing the purity and composition of foods and drugs. In 1927, the Bureau of Chemistry effectively disbanded when its powers were reorganized under a new U.S.D.A. body, the Food, Drug, and Insecticide Organization (later the Food and Drug Administration).