Nuclear Museum Logo
Nuclear Museum Logo

National Museum of Nuclear Science & History

James F. “Jim” Nolan was a Captain in the US Army Medical Corps, the Chief Medical Officer for the Los Alamos site of the Manhattan Project, and a Special Consultant to Project Alberta on Tinian Island. An early recruit to the Manhattan Project, he was deeply involved in the history of the atomic bomb throughout the project and beyond.



Nolan was a medical doctor specializing in radiology, obstetrics and gynecology, and surgery. He graduated from the medical school at Washington University in St. Louis in 1938. While at Memorial Hospital in New York, he applied in 1942 for a commission in the US Army Medical Corps. Around the same time, he was recruited to the Manhattan Project by Dr. Louis Hempelmann, his friend, former classmate, and fellow radiologist. Hempelmann had been recruited by J. Robert Oppenheimer, whom he had met at the University of California, Berkeley.

The pair of radiologists were the first two doctors at Los Alamos, and arrived together in the spring of 1943. Hempelmann was still a civilian, but Nolan was assigned there as part of his official Medical Corps service. At that point, the New Mexico site had a fraction of the population it would reach by the war’s end. Nolan supervised normal medical services, while Hempelmann oversaw the “special hazards” of atomic research. Their roles were not completely separate; each man assisted the other.  

In his role as Chief Medical Officer at Los Alamos, Nolan had to supervise a variety of projects, from sewage to inoculations. In 1943, the population of the site increased rapidly. The composition of its inhabitants changed too, as scientists’ families joined them, including Nolan’s own wife and young son. In order to cope with the new arrivals, Nolan requested that the post hospital be expanded from the existing 30-bed facility. He was eventually authorized to expand to 54 beds. The arrival of families also meant many pregnancies. Nolan delivered almost every baby born at Los Alamos during his tenure there.

He supervised every type of medical specialist at Los Alamos—including the veterinarians who cared for the Army’s dogs and horses. Despite the growing population, the site had a severe lack of essential specialists. There was no on-site dentist until March 1944, and no psychiatric professional (a crucial role in the stressful research environment) until August 1944.

Nolan eventually became a part of the Health Group, a staff started by Hempelmann that dealt with radiation and safeguards. It reported directly to Oppenheimer. Nolan resigned his other duties in order to work full-time with the Health Group in 1945. He had a significant hand in some of the rules that were implemented, including establishing an evacuation plan for Los Alamos (which General Leslie Groves had initially deemed unnecessary).



In his capacity with the Health Group, Nolan was placed in charge of safety for the Trinity Test. Safety was not the military’s top priority, however. In Nolan’s own words, “Possible hazards were not too important in those days. There was a war going on.” There was also an incomplete view of all the weapon’s effects: “The bomb was designed as a weapon of warfare primarily utilizing blast and heat for destructive forces…radiation hazards were entirely secondary.”

Nolan’s top priority was recovering data about the blast (radiation-related and otherwise). A secondary role was measuring if there was dangerous radiation, and notifying the proper authorities. Just before Nolan completed the Health Group’s safety plan (which was submitted on June 23), Joseph Hirschfelder and John Magee from the Theoretical Division issued a report on a worst-case scenario for fallout from the test. Though Nolan was confident in the site’s safety even if that worst-case scenario came to pass, the results validated his earlier insistence on an evacuation plan.

Nolan did not attend the Trinity Test, however. He had been assigned to another important task: transporting components of the Little Boy bomb to Tinian Island in the Pacific. He and Robert Furman set off on a journey with a crate containing the bomb mechanism and a canister of uranium. Nolan, as a radiation specialist, had been chosen for his ability to monitor the uranium. Their cargo was only part of the bomb: the rest was transported by air to Tinian with Lieutenant R. A. Taylor Jr. and Lieutenant Colonel Peer de Silva.

On July 14, Furman and Nolan went from Los Alamos to Santa Fe and then to Albuquerque via truck. Disaster almost struck when a tire blew, sending the truck careening towards the edge of a mountain road. From Albuquerque, they flew to Hamilton Field in San Francisco. At a nearby port, the men and the bomb materials boarded the USS Indianapolis, a Navy cruiser that would bring them to Tinian. The ship departed on July 16, after Furman and Nolan were notified of the success of the Trinity Test.

The two Manhattan Project men were disguised as Army artillery officers. The crew of the Indianapolis were not informed of the details of their mission, and became slightly suspicious. Nolan was not a very convincing artillery officer: when asked what size shells he worked with in the Army, he could not come up with an answer and just gestured with his hands. He became very seasick on the voyage, which provided a convenient cover for his constant trips to check on the uranium canister.

On July 26, Furman and Nolan disembarked at Tinian. The Indianapolis continued on, and would eventually meet a grisly fate. Nolan served on the island as a special consultant to Project Alberta, the group charged with assembly of the bombs. He also assisted ground crews of the 509th Composite Group, as an expert on radiation and its detection.



After the bombings of Hiroshima and Nagasaki and the Japanese surrender, Nolan joined Furman for another mission: investigating the effects of the bombs on those Japanese cities. He continued to assist with military nuclear research for a number of years, including participating in nuclear testing at Bikini and Eniwetok Atolls. He went on to research treatment for gynecological cancers. 

Nolan’s role in the Manhattan Project has been remembered in various ways. Children of Manhattan Project veterans remembered his role in delivering babies. He was the subject of a poem in John Canaday’s poetry collection Critical Assembly. He was also fictionalized in John Adams’s opera Doctor Atomic, in which Nolan informs General Groves about the toxic properties of plutonium.



James F. Nolan's Timeline
1943 Mar Visited Los Alamos for the first time.
1945 Joined Hempelmann's Health Group full-time.
1945 Jun 23rd Submitted Trinity Test safety plan.
1945 Jul 14th1945 Jul 26th Transported the Little Boy components from Los Alamos to Tinian.

Related Profiles

John Caughey

Los Alamos, NM

T.Y. Quarles

Hanford, WA

Carlilie E. Choate

Los Alamos, NM

Walter L. Fischer

Los Alamos, NM