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Max Delbrück Papers

Identifier: 10045-MS

Scope and Content of Collection

The material is divided into ten sections and encompasses Delbrück's entire lifetime, from 1906-1981. The bulk of the records is related to his professional life and focuses on the years between 1930 and 1980. While the most interesting section is the personal correspondence, the total collection chronicles Max Delbrück's role in the development of molecular biology. There is also abundant evidence of the strong personality that attracted attention and even devotion from scientists and nonscientists alike.


  • 1918-1997


Language of Materials

English, French, & German


The collection is open for research. Researchers must apply in writing for access.

Publication Rights

Copyright may not have been assigned to the California Institute of Technology Archives. All requests for permission to publish or quote from manuscripts must be submitted in writing to the Caltech Archivist. Permission for publication is given on behalf of the California Institute of Technology Archives as the owner of the physical items and, unless explicitly stated otherwise, is not intended to include or imply permission of the copyright holder, which must also be obtained by the reader.


Max Delbrück was born in Berlin in 1906, the youngest member of a large, intellectual family. His father was professor of history and his uncle professor of theology at the University of Berlin. Seeking his own identity in a highly distinguished family, Delbrück decided to study astronomy during high school. He continued his studies at the universities of Tübingen, Bonn and Berlin. He intended to do his dissertation at Göttingen in astronomy, but switched to theoretical physics. He worked under Max Born as a teaching assistant while doing his research under W. Heitler, and received his doctorate in 1930.

Delbrück went to Bristol in 1929 to work with J. E. Lennard-Jones. He returned to Göttingen to take his oral exams, which he passed only on his second attempt. He later admitted that he had not bothered to study for them the first time. During 1931-1932, he studied with Niels Bohr in Copenhagen, and W. Pauli in Zurich, courtesy of a Rockefeller Fellowship. Bohr, in particular, had a major influence on Delbrück, and provoked his interest in biology with the claim that the complementarity principle of quantum mechanics could be applied to other sciences, especially biology.

Upon his return to Berlin, he worked for five years as Lise Meitner's assistant at the Kaiser Wilhelm Institute for Chemistry. In 1937, he came to the California Institute of Technology on a Rockefeller Foundation grant. He selected Caltech because of biologist T. H. Morgan's work with drosophila genetics, but was soon working with E. L. Ellis on bacteriophage.

Delbrück had already learned that his academic progress would be hampered in Germany by his antipathy to Nazism, and by 1940 the worsening political situation reinforced his decision to remain in the United States. With the help of the Rockefeller Foundation, which paid half of his salary so he could continue his research, he moved to the physics department at Vanderbilt University in Nashville, Tennessee. At this time, he met and began his collaboration with A. D. Hershey, then at Washington University in St. Louis, and S. E. Luria, then at Columbia University in New York. The three men were pioneers in the field of molecular genetics, and in 1969 they shared the Nobel Prize in Medicine and Physiology for the work they had done during the 1940s.

In 1941, Delbrück began his forty-year association with Cold Spring Harbor Laboratory. In the course of those years he gave papers, taught classes, and organized and attended meetings. He also inspired other scientists, not only with his specific interests but with his spirit of enthusiasm and camaraderie.

He returned to Caltech in 1947 as professor of biology. During the fifties, his interest in phage and molecular genetics gave way to an interest in phycomyces and the sensory transduction of signals, an interest that persisted throughout his life.

Delbrück left Caltech briefly on two occasions. From 1961-1963, he organized the Institute of Genetics at the University of Cologne in Germany. And in 1969, he helped organize the natural science faculty at the new University of Konstanz, where he returned regularly as guest professor.

In 1977, Delbrück retired from his position as Albert Billings Ruddock Professor of Biology and was named Board of Trustee Professor Emeritus in recognition of his achievements and his desire to continue his research.

On March 9, 1981, Max Delbrück died at the age of 74. Though he had been ill for some time before his death, he was in the midst of writing an autobiography, as well as preparing a lecture to be delivered at the Poetry Center in New York titled, "Rilke's Eighth Duino Elegy and the Unique Position of Man." At a memorial service held at Caltech, he was remembered as friend, scientist, philosopher, and humanist. To varying degrees, all these aspects of Max Delbrück are illustrated in his collected papers.


22 linear feet (47 boxes)


This collection encompasses most of Delbrück's lifetime and chronicles his role in the development of molecular biology. The bulk of the materials date from the time of his immigration to the U.S. in 1946. They include personal and professional correspondence, lectures, manuscripts, and biographical material. These materials relate to topics such as his immigration as a German scientist during the early years of World War II; biophysics; his work with the Phage Information Service; his teaching and collaboration with students; and Cold Spring Harbor Laboratory.


Section I, Personal Correspondence, makes up more than half the collection and covers the years 1932 to 1981. There are letters which predate Delbrück's departure from Germany, though not many; and there are letters written and received only days before his death. The bulk of the correspondence falls in the 1960s and 1970s, but there is a substantial amount from the 1940s and 1950s as well. Not only was Delbrück a prolific letter writer who kept copies of nearly all his letters; he received much unsolicited correspondence, invitations, requests of one sort or another, and what can best be called fan mail.

The earliest letters in this section are part of the Bohr Institute's Max Delbrück-Niels Bohr correspondence, copies of which have been deposited in the Caltech Archives, courtesy of the Bohr Institute. Delbrück's pre-1946 correspondence was left behind in Germany and has never come to light.

Nearly all of Delbrück's letters are in English. Many people, however, wrote to him only in German, and a few in French.

Letters are arranged chronologically within the alphabetically ordered folders. Incoming and outgoing letters are filed together. These files often contain information relevant to another section. For example, this section contains scattered files on organizations; correspondence regarding Delbrück's 1946 job offer at Manchester is filed under P. M. S. Blackett; and information about Delbrück's involvement in human rights issues is contained in the files of Florey, Frucht, Harrington, Kistiakowsky, Kovalev, Lissouba, Medvedev, and Myrdal.

Many of the files in this section cover two decades; even more, in the case of his closest friends and colleagues. These long-term exchanges reveal the maturation of molecular biology, as well as of the men themselves. Of particular interest on both counts are the files of Seymour Benzer (1949-1977), A. D. Hershey (1944-1977), S. E. Luria (1947-1980), and James Watson (1949-1976). Delbrück's correspondence with Bohr (1932-1962) illustrates the exchange of ideas which followed Delbrück's initial response to Bohr's theories, as illustrated in the following passage from Bohr: "I am also again coming into the epistemological problems and it was a pleasure for me a few days ago at the 50th anniversary of the Danish Biological Society to give a lecture about the relation between physics and biology, in which I used some of the illustrative examples from your notes. I hope in the very near future to take up the challenge and to restate and develop my general views, the formulation of which I hope to be able to essentially improve." (Niels Bohr to Max Delbrück, March 28, 1946)

In Section II, Correspondence and Documents: Educational Institutions, the most important papers relate to Caltech, the University of Cologne, and the University of Konstanz, by virtue of Delbrück's affiliation with these institutions. The latter two files are mainly in German. The file on Gustavus Adolphus College concerns the Convocation of Nobel Laureates, to which Delbrück was invited on several occasions, and which he attended in 1977. At that time, he was awarded an honorary Doctor of Science degree. Vanderbilt University papers are filed in this section, but for correspondence regarding Delbrück's appointment there, see Section IX, Biographical and Personal Material.

Section III, Professional Oganizations and Meetings, is dominated by the Cold Spring Harbor files. Particularly interesting are the materials from the first phage courses, given in 1945 and 1946, and the dedication of the Max Delbrück Laboratory in 1981.

Section IV, Technical Files, contains nearly all issues of the Phage Information Service between 1947 and 1959. These were bulletins designed to circulate information informally in a rapidly developing field. A small amount of miscellaneous technical information is filed under Course Lectures and Notes in the back of a notebook used in a class on UV radiobiology.

A variety of materials are classified under the headings Lectures and Manuscripts in Sections VII - VIII: course lectures and notes, lectures, manuscripts, reprints, book reviews, books, and papers by other writers.

The lectures are noteworthy for their philosophical nature. Delbrück placed great importance on exploring the relationships between science and other aspects of life. He was an excellent writer, entertaining and thought provoking. The lectures were intended for a variety of audiences and occasions, from graduating seniors at commencement ("The Arrow of Time - Beginning and End") to Nobel Laureates at Convocation ("Mind From Matter?").

In the S. E. Luria file, under "Papers by other writers," there are papers not by Luria, which Delbrück filed under his name - evidently because of an association with Luria or his work.

Section IX, Biographical and Personal Material, consists of personal papers regarding various aspects of Delbrück's life and his family. The most important papers document his immigration as a German scientist during the first years of World War II. These are filed under "Immigration"; other relevant papers are under "Habilitation" and "Vanderbilt appointment."

Delbrück was the recipient of many awards and honors, not all of which are documented in the collection. Examples for which there are no files include the Royal Society of London and the Royal Danish Academy of Sciences. Information regarding the Nobel Prize is located in this section, and also in Section VII, under "Mind From Matter?," Delbrück's Nobel Conference lecture, and in Section II, under Gustavus Adolphus College. In addition, there is a microfilm copy of Delbrück's scrapbook, "The Road to Stockholm," in Box 44.

The supplemental material donated by Manny Delbrück (Boxes 45 - 47) includes both printed and manuscript material. The largest portion is the correspondence between Delbrück and his students and postdocs, a few pieces of which date from after his death. These include responses by either Ray Owen or Manny Delbrück. Finally, there are photocopies of a few documents from the Nazi period and other material relating to German politics.

Acquisition Information

Max Delbrück donated his papers to the Caltech Archives in several installments, beginning in 1968. The collection is comprised of forty-seven boxes, of which the last three were donated after Delbrück's death by his widow, Manny. Three more boxes of material retained by Manny Delbrück up to her death in 1998 were donated by Paul MacCready.

Related Collections

For further biographical information on Max Delbrück, see his oral history, done by Carolyn Kopp in 1978, which is deposited in the Caltech Archives.

There is a small amount of Delbrück correspondence filed in other collections in the Archives. See the Don Yost collection under K. E. Zimens, the Biology Divisional Records, the papers of Emory L. Ellis, and the papers of George Beadle.

Processing History

This collection was processed by Carol Bugé in Fall 1982. The finding aid was revised by Charlotte E. Erwin in August 1999 and February 2002.

Guide to the Papers of Max Delbrück, 1918-1997
Processed by Carol Bugé. Revised by Charlotte E. Erwin.
Description rules
Describing Archives: A Content Standard
Language of description
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Repository Details

Part of the California Institute of Technology Archives and Special Collections Repository

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