Harold Urey—A Personal Remembrance: Part II

After five days, it was over and we were driving back to New York City. At first Urey said nothing about jobs. One incident seemed to weigh on his mind. He had been in a bar with friends when he was photographed by a reporter, and he was worried that if the photo might be published in the newspaper, his teetotaler folks in Kansas would recognize the background. Finally, he told me sadly, “Nobody wants you.” Not too surprising, since I was female and Jewish. It was the same old story. Recruiters from all the big chemical companies had been on the campus in the spring. Despite the Depression, Columbia had such an outstanding chemistry department that DuPont, Standard Oil, U.S. Rubber, and so on would each hire one graduate. Notices of the recruiters’ visits would be posted on the departmental bulletin board reading, “Mr. So and So from X company will interview all prospective Ph.D.s of this year. Male, Christian.” I was out on two counts. From the Rochester experience, it was obvious that discrimination was equally rampant in academe.

Following other futile attempts to find me a post, Urey offered me a postdoctoral position in his laboratory as a temporary solution. I accepted with alacrity. Soon thereafter David Rittenberg and Rudolf Schoenheimer from the Columbia University medical school alerted me to an opening in biochemistry. Rittenberg had preceded me as a student of Urey’s, and he and Schoenheimer were pioneering a new field, the use of isotopic tracers to study metabolism. One of the up-and-coming biochemists, Vincent du Vigneaud, from George Washington University, had appealed to them to find a postdoctoral fellow who could introduce the necessary techniques in his laboratory. And they suggested me. When he discovered that their candidate was a woman, as I later learned, he demurred. Whereupon they informed him that I was the only one in the country who was qualified, and he offered me the position.

I sought Urey’s advice, and he thought I should accept. He pointed out to me that if I stayed on at Columbia, I would always be regarded as a graduate student by the faculty, but if I went elsewhere, I would be treated as a professional. Also, he believed this new area of research held great promise. I did too. Another attraction of the field of biochemistry to me was the knowledge that there were many more women in that field than in physical chemistry. I accepted the position but was disappointed to find out when I arrived in Washington that I was the first woman du Vigneaud had ever hired.

After I had been at George Washington University a few months, Urey came to Washington and visited me in the laboratory. The medical school was old, shabby, and grimy and the stone stairs leading to my laboratory were hollowed out from the steps of hundreds of students who had used them since the building had opened. When Urey appeared in the minuscule space that had been assigned to me, he began without any preamble to tell me about his visit to Cambridge University in England, where he had been shown the dismal, dusty basement of the ancient Cavendish Laboratory where the great James Clerk Maxwell had lectured and conceived the electromagnetic theory. The take-home lesson of his story was that there was no relationship between the elegance of the physical environment or the lack thereof and scientific creativity.

When Urey attended the spring meeting of the American Physical Society in Washington in 1938, I went there to meet him. Unexpectedly I witnessed a historic encounter. As we stood chatting on the lawn of the Bureau of Standards, E. O. Lawrence of Berkeley came by. Urey introduced me to him, telling him that I was a former student of his who was using stable isotopes as tracers to investigate metabolism. He added with unaccustomed taunts that Lawrence had no radioactive isotopes that were appropriate for solving biological problems. “For hydrogen, we have deuterium, you have nothing [tritium had not yet been discovered]; carbon, we have carbon-13, you have carbon-11 with a half-life of 20 minutes; nitrogen, we have nitrogen-15, you have nothing; oxygen, we have oxygen-18, you have nothing.” Lawrence returned to Berkeley from that meeting and, as I later learned from Martin Kamen, met with his group and said, “We have to find a radioactive isotope with a sufficiently long half-life to be useful to the biologists.” Soon after, Samuel Rubin and Kamen found carbon-14, the isotope that had the most profound effect on research in biology.

It was not until June 1942 that I saw Urey again. At the time I was still working with du Vigneaud, now at Cornell University Medical College in New York City. I had taken a few months leave after the birth of my first child in May, and I had time to visit Urey. The United States had already entered the war, and most scientists had become involved with war research. At Columbia, Urey headed a project called SAM (substitute alloy materials), which was focused on one aspect of the highly secret atomic bomb project, the separation of the uranium isotopes, essential since only uranium-235 is fissionable. Urey asked me to work on the project without revealing what it was, only telling me that I would have to work every day until midnight. He introduced me to his other visitor, J. Robert Oppenheimer, who became the research director of the atomic bomb project. Although I was most anxious to help the war effort, I turned down Urey’s request for two reasons. First, as a new mother, I didn’t feel that I could work the hours the job demanded, and, second, I thought the work I was doing in du Vigneaud’s laboratory—and his policy on wartime research—had considerable merit. He believed that some day this war would be over, and he thought at least a skeleton group should keep basic science going for continuity. Thus all the young men in our lab who were draftable were engaged in war research under his supervision (the synthesis of penicillin), but I, one older assistant professor, and the graduate students continued to do basic research. In retrospect, I do not regret my decision to continue in du Vigneaud’s group.

After the war was over, Urey left Columbia for the University of Chicago and also changed his field of research, devoting himself to geochemistry. Around that time I moved to Washington University in St. Louis. In the early 1950s I had occasion to be at a meeting in Chicago, and I visited Urey. He was really upset with the military use of the atomic bomb in Japan and told me that never again would he work on any research that could possibly have military application. In fact, he refused to buy enriched isotopes from the Atomic Energy Commission, although they would have been most useful in his ongoing research. Again, he was being naïve, because in order to avoid obtaining the isotopes from the AEC, he had developed a most sensitive mass spectrometer, which could measure differences in isotopic concentrations from various natural sources. It didn’t occur to him that some day that might be very useful for weapons research. However, I admired his moral indignation.

His research involved determining the temperature of the ocean in which some marine fossils had lived from the oxygen-18 content of their carbonate, and he wanted to confirm it with an independent measurement. From my research, I was able to tell him that phosphate as well as carbonate equilibrated its oxygen with water in living systems. Subsequently, he measured the oxygen-18 content in his fossil’s phosphate and confirmed the temperature of the water in which they had lived. To my surprise, I was acknowledged in a footnote in a paleontology journal.

The next time I heard directly from Urey was in the spring of 1971, when I was elected to membership in the National Academy of Sciences. He was at the meeting in Washington, and he immediately called me to tell me the news; he was so excited that his voice was an octave higher than normal. I was touched by his pleasure.

The last time I saw Urey was in 1978 at a dinner in La Jolla in honor of the 65th birthday of a colleague of his who was also a former colleague of mine, Martin Kamen. Naturally I went to greet my old professor, and I was deeply upset because he did not recognize me. As I later learned, he was practically blind and suffering from Parkinson’s disease. He subsequently died of the disease in January 1981 at the age of 87.

In 1982, shortly after Harold Urey’s death, the History Division of the American Chemical Society celebrated the 50th anniversary of the discovery of deuterium with a symposium, and I was one of the invited speakers. All the other speakers were more recent associates of Urey. At the luncheon after the symposium, I sat next to Mrs. Urey, and she said, “Harold was so proud of you.” That accolade meant more to me than any recognition I have received in my scientific career.

For Further Reading

Arnold, James R.; Jacob Bigeleisen; Clyde A. Hutchison, Jr. “Harold Clayton Urey, April 29, 1893–January 5, 1981.” Biographical Memoirs of the National Academy of Sciences. http://www.nap.edu/html/biomems/hurey.html.