Postwar Gilman
Following Lewis's retirement from administration in 1941, Latimer became dean of the College of Chemistry, a position he held until 1949. He persuaded Melvin Calvin, a physical-organic faculty member who had worked with Lewis, to resume Ruben and Kamen's research on the use of carbon-14 as a tracer in photosynthesis. Calvin established his headquarters in the Old Radiation Laboratory. In 1961, he received the Nobel Prize for his studies in photosynthesis. Latimer was dean when the Division of Chemical Engineering was established in 1946 in Gilman Hall. With the support of Hildebrand and Pitzer, who followed him as deans, chemical engineering became a full department in 1957.

As the chemistry department grew and moved into newer facilities, the chemical engineering department expanded to occupy all of Gilman Hall. By 1948, the famous seminar room, 102, was too small for research conferences, and it was remodeled into administrative space. The attic rooms are still used for chemical engineering research, but most of the shops have been moved. The subbasement has been remodeled into an undergraduate chemical engineering laboratory.

Even after the addition of more modern buildings, Gilman Hall remains a central part of the College of Chemistry. It is a well-designed, skillfully constructed building. In California, where buildings are rated for earthquake hazards, Gilman Hall has about the same rating as most of the campus buildings built 50 years later. The symbol of the westward movement of science and technology, Gilman Hall continues to serve the purpose for which it was builtºeducation and research in the chemical sciences.