Photograph of Dorothy Semenow

Dorothy Semenow, from a 1953 article in Engineering and Science magazine announcing her admission

In 1953, Dorothy Semenow became the first woman formally admitted to Caltech as a student in 43 years. Although Throop was originally coeducational, President James Scherer had stopped admitting women in 1910. His policy remained until organic chemist John D. Roberts joined Caltech’s faculty from MIT and asked the Institute to allow Semenow, his graduate student, to come with him. With Pauling’s support, the faculty and trustees approved. Semenow earned her PhD—for a dissertation on conversions of aryl halides to arylamines—in 1955, then a second PhD in psychology from Claremont Graduate University. She worked both as an independent psychotherapist and as a professor of biochemistry at Pomona College and UCLA.

“A Nobel Laureate, advising on physics courses, greeted me with ‘Oh, so you’re the one who caused all the trouble.’ I thought he was kidding, but later learned he wasn’t. A bit of density helps at times like that. I found a gamut of sentiments toward the actual presence of a female student in this male sanctuary. A minority openly opposed; some welcomed woman even into the inner sancta of their very own research groups; and some were in-between, having voted pro, but somehow uncomfortable with the living animal.”

—Dorothy Semenow, writing of the pseudonymous “Toptech” in Experiences in Being, 1971

Photograph of Marjorie Caserio

Marjorie Caserio, 1962

Marjorie Caserio joined Roberts’ lab as a postdoctoral fellow in 1956, and collaborated with him on the widely-used textbook Basic Principles of Organic Chemistry. The new University of California, Irvine, hired Caserio as an assistant professor in 1965; she went on to chair the chemistry department there and to serve as vice chancellor of academic affairs at the University of California, San Diego.

Photograph of Justine Garvey

Justine Garvey, 1963

Immunochemist Justine Garvey came to Caltech as a research fellow in 1951 and remained a member of the research staff, studying the persistence of foreign antigens in animal tissues, for 23 years. She was, according to her supervisor Dan Campbell, “a major factor in the development of the status of immunochemistry at Caltech,” collaborating with him on dozens of journal articles and on the textbook Methods in Immunology. When Campbell retired in 1974, Garvey moved on to became an associate professor at Syracuse University.

Caltech had just begun admitting women as undergraduates when the era of chemistry in Gates Laboratory came to an end, a casualty of the San Fernando earthquake. In its later homes, Caltech’s chemistry division has continued to grow more diverse in demographics and in research programs.

Photograph of Ahmed Zewail

Ahmed Zewail

Ahmed Zewail grew up in Egypt and came to Caltech in 1976 after attending Alexandria University and the University of Pennsylvania. His innovative work in femtochemistry—the use of ultrafast lasers to observe chemical reactions as they actually happen—earned Zewail the Nobel Prize in 1999, and dozens of other scientific awards. As Linus Pauling Professor of Chemistry, Zewail followed in Pauling’s footprints by engaging in politics as well as science; he was an outspoken advocate for science, education, and economic growth in Egypt, particularly after the 2011 protests in Cairo’s Tahrir Square. Egypt’s Zewail City of Science and Technology—an institute of learning, research, and innovation—was named in his honor.