Wilhelm's Way: The Inspiring Story of the Iowa Chemist Who Saved the Manhattan Project

By Teresa Wilhelm Waldof

Winner of the Minnesota Book Award

Recipient of the Excellence in Iowa History Award

The untold story of the humble man whose scientific innovation helped end World W

• Language: English
• Publisher: Third Generation Publishing
• Release date: Jan 25, 2022
• ISBN: 9798985439618

Teresa Wilhelm Waldof

Independent scholar Teresa Wilhelm Waldof is the world's leading expert on the Ames Project section of the Manhattan Project. She speaks on Dr. Wilhelm's life and scientific contributions, the Ames Project, and the founding of Ames Laboratory. She holds a BA in speech communications and an MBA from the University of Minnesota. She lives in Rochester, Minnesota, with her family.

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Wilhelm's Way by Teresa Wilhelm Waldof

WILHELM’S WAY

WILHELM’S WAY

THE INSPIRING STORY OF THE IOWA CHEMIST WHO SAVED THE MANHATTAN PROJECT

TERESA WILHELM WALDOF

Third Generation Publishing

Wilhelm’s Way: The Inspiring Story of the Iowa Chemist Who Saved the Manhattan Project

Published by Third Generation Publishing, Rochester, Minnesota

Copyright © 2022 by Teresa Wilhelm Waldof. All rights reserved. Aside from brief passages in a published review, no part of this book may be reproduced or transmitted in any form or by any means, electronic or mechanical, including all technologies known or later developed, without written permission from the publisher. For reprint permission write to [e-mail].

Print ISBN 979-8-9854396-0-1

E-book ISBN 979-8-9854396-1-8

Library of Congress Control Number 2021925742

Cover design by Rebecca Neimark, Twenty-Six Letters

Cover photo courtesy of the Wilhelm family’s private collection

E-book production by Erica Smith, Ebook Conversions

In honor of Elvin O. Waldof,

the 56th Armored Infantry Battalion,

and

every soldier—past, current, and future—committed to the defense and preservation of freedom, democracy, and the United States Constitution

The soldier above all other people prays for peace, for he must suffer and bear the deepest wounds and scars of war.

—Douglas MacArthur, "Duty, Honor, Country:

Address at West Point," May 12, 1962

Contents

Introduction

Prologue

PART 1: NO PURE URANIUM, NO ATOMIC BOMB

1. The Uranium Problem

2. A Change in Life’s Trajectory

3 There’s No Substitute for Genius

4. Safe but Not Secure

5. Spontaneity Is Not Always a Good Thing

6. Don’t Be a Boron

7. Casting Director

8. The Bismuth of Scientific Discovery

9. Thermite Be a Breakthrough Moment

10. Wilhelm’s Secret Cargo

PART 2: FROM WHENCE HE CAME

11. The Way to Iowa

12. The Boy from Pumptown

13. A Bright and Dark Summer

14. Hoops and Hopes

15. Victory Is Contagious

16. The Green Suit

17. Is That All You Got?

18. Lil Chance of Making It

19. The Registrar’s Assistant

20. A Bulldog for Life

21. The Roaming Twenties

22. To Helena and Back

23. Stepping Up

24. A Century of Progress

25. Pass the Zinc, Please

26. Spud, Spectrography, and Metallurgy

Photo Gallery appears at the end of Part 2.

PART 3: METALS MAN FOR THE AGES

27. This Is Pure Uranium

28. Quik Phix

29. A Chain of Events

30. Barrels of Fun, Fire, and Fulfillment

31. Espionage in Ames

32. Fast Feed

33. The Realities of War

34. You Could Patent That Idea

35. The Peace of Uranium

Epilogue

Acknowledgments

Notes

Bibliography

Photo Credits

Index

Introduction

A striking achievement among the many associated with the wartime atomic energy project in the United States was the production of many tons of pure uranium by a group consisting of faculty and students working in a misused building on the campus of the Iowa State College at Ames.

—Samuel Glasstone, Sourcebook on Atomic Energy

Oak Ridge, Hanford, Los Alamos. These are the places that history books and our common awareness associate with the Manhattan Project. Movies, books, and other media recount the historic discoveries and events that took place at these locations. Implicit in these versions is that these three sites were the only or at least the most important ones involved in the development of the atomic bomb.

Historians have narrowed the focus in order to simplify the story of what is considered the most complex and largest-ever collaborative endeavor involving government, academia, and industry. In doing so they have left out important, even critical details. More than thirty sites across the United States were part of the project. Most have never been widely acknowledged for their efforts.

While the Manhattan Project physicists had a theory that a controlled self-sustaining nuclear chain reaction could be achieved, the reality was that without the work of chemists it would have been impossible to prove. Working with uranium is not for the faint of heart. The element is dangerous and often explosive. It was the ingenuity of a chemistry professor at Iowa State College that played a critical but little-known role in the success of the Manhattan Project.

Dr. Harley Wilhelm led a small, ragtag team that produced the pure uranium needed for the world’s first controlled self-sustained nuclear chain reaction. Furthermore, his mass production process made available the quantities of uranium needed to transmute uranium to plutonium. Wilhelm’s Way reveals the untold story of the man whose humble nature, brilliant mind, and remarkable leadership made it possible for the atomic bomb to be built and deployed.

The original historical account of the Manhattan Project for consumption by the public was written by Henry D. Smyth, himself a physicist. It has been criticized as being biased toward the science of physics and lite in explaining the role of chemistry in the project.

Richard Rhodes’s Pulitzer Prize–winning account, The Making of the Atomic Bomb, is the most comprehensive. His highly acclaimed book is invaluable in revealing the historical context, the multidimensional aspects, and the key personalities involved in this remarkable wartime effort. Anyone who wants to understand the Manhattan Project should read his book. It provides insights on vital documentation while bringing together the many facets of the project for the reader.

But Rhodes does not discuss the first imperative of the project: solving the uranium problem. Wilhelm, though integral to the success of the entire project, is not mentioned as having solved it. Rhodes references uranium arriving from Iowa, yet he misstates the amount. Furthermore, there is no mention of the fact that without the work done by Wilhelm, the history-making experiment of December 2, 1942, likely wouldn’t have succeeded.

Scientific minds had worked on the problem of purity for over one and a half centuries. In the unlikely event that a solution was found, someone would still need to develop methods for its mass production. There was no guarantee that either could be achieved. Critics may say that necessity is the mother of invention. Consider that scientists at Princeton University, Columbia University, University of Chicago, Westinghouse, Metal Hydrides, the National Bureau of Standards, and elsewhere all failed. All worked under the same pressures, time constraints, and shortages of resources as Wilhelm. Why was Wilhelm the person able to achieve the needed outcomes? Wilhelm’s Way introduces the man and his mettle along with the pivotal life events that led him to be where the nation and the world needed him to be at just the right moment.

Harley Wilhelm was my grandfather. As a child I knew him as the lovable man who gave me horsey rides on his back. He always boasted that because he’d sat up to the organ with his grandchildren, letting them pound the keys at will, he’d given each their first music lesson. He was keen at math and chortled with pleasure when I, at the age of five, told him I had finished learning arithmetic because I had successfully completed kindergarten.

Not until my young adulthood did I become aware of the significance of my grandfather’s work. My parents insisted I drive to Iowa in June 1986 for the dedication ceremony of Wilhelm Hall at Iowa State University. I was surprised to see the news media there. In his remarks during the ceremony Dr. Louis Ianniello from the Department of Energy said, If it weren’t for Harley Wilhelm we’d all be speaking Japanese right now. I took note. It was the day I learned that my grandfather was the chemist who made it possible for the United States to build the atomic bomb and end World War II.

Over the years I came to understand much more about my grandfather’s contributions to the Manhattan Project. I heard many stories about his life and recognized that it was filled with pivotal moments that, had they turned out differently, could have meant a much longer war or perhaps even a different outcome. He pondered once in an interview, It’s interesting, the narrow margins by which people do things. I don’t know if he was referencing his own experience, but indeed, his life was just that, one of narrow margins. I was inspired by the story of where he came from, the life he led, and his impact on our world today, and as I began to work on this book, I found that others felt the same way.

I had the good fortune to interview individuals who were either active participants in or spouses of people who worked on the Ames Project. I can attest that seventy-plus years is a long time to remember specific details. The years have faded some memories, and those who do remember often have incomplete recollections or mix up the details in the retelling. I have made every effort to find supporting documentation for the stories told in this account. Nevertheless, what they recounted is what they lived themselves.

There are likely many other important stories about the project that have not been uncovered. Time is now short for them to be recorded. All the leading players died decades ago; firsthand accounts by those in charge, unless documented or recorded prior to their deaths, are lost forever. The youngest technicians, secretaries, and laborers who worked on the project, if still living, are in their nineties as of this writing.

After my presentations about Dr. Wilhelm and the Ames Project, I always take questions from the audience. One inevitable question is, How did Dr. Wilhelm feel about the United States having used the atomic bomb? I don’t recall ever asking my grandfather how he felt about Truman’s decision. But I knew him. He was a patriot—a man who answered the call to duty by a nation that needed his expertise, a nation that had suffered an unprovoked attack and was engaged in a brutal war in which tens of thousands of its citizens were destined to die.

Others did ask him the question. When interviewed by historian Laura Kline in 1987, he described his reaction to the moment he and others learned about the discovery of fission and grappled with the enormity of consequence it introduced. Then he voiced his reality and what I believe was a driving force behind the intensity with which he pursued the task at hand: Now we find ourselves in a race. Who’s gonna get it first? If Germany gets it, what would happen then? If Italy gets it first? And if Japan got it first, what would happen? So well, even if Russia got it first, what would happen? Where would we be today if Russia had gotten the atomic bomb first? We’d probably be worse off than if Germany had gotten it first.

Manhattan District History (www.osti.gov/opennet/manhattan_district) is the US government’s compilation of final reports of the primary working groups on the project. The eight books of the history comprise thirty-six volumes, and in them are details of the work done by Wilhelm and his team in Ames. Book 7, Feed Materials, Special Procurement and Geographical Exploration, acknowledges the unique challenges: The feed materials program is a particularly intriguing and interesting subject, dealing as it does chiefly with the material uranium. . . . Its scarcity and source control by national government and other major international organizations, the extreme secrecy with which all operations had to be continued, the magnitude of the quantity involved, and the speed with which manufacturing plants had to be constructed and the products obtained, as well as the personalities and organizations involved, made the program one of the highest importance.

Chapter 11 of the fourth volume in book 1 features the documentation submitted by the Ames Project group. The introduction explains,

It was also necessary to develop a large number of chemical and metallurgical processes in order to produce the raw materials to be employed in the atomic weapons. The Ames Project made many important contributions in these fields and was particularly successful in the pioneering stages of such developments. Frequently the need of special processes was outlined at Ames and a method of attack was developed. . . . There was also the problem of obtaining vital raw materials. Frequently these materials were not made by industry, or the known industrial processes were inadequate for the manufacture of these materials in sufficient quantities at the required purity. The Ames Project was eminently successful in developing processes and supplying many of these materials.

A sharecropper’s son from southern Iowa was an unlikely character to change world history. Dr. Wilhelm’s life is a story of hope, resilience, and humility. Wilhelm’s Way provides an important and missing link in the history of the Manhattan Project. But, more importantly, it is an American success story, one that I hope will inspire you.

Please note that throughout the book you will see use of both imperial and metric systems. To accurately represent experiments, meetings, and other records, measurements are stated as found in source materials.

Prologue

Nearly every morning the old man walked out the front door of his house and made his way toward campus. The only thing he carried with him was a metal key, which he tucked away in his coat pocket. When he arrived at the metallurgy building, he made his way down the wide hallway, shuffling his feet as he moved closer to the laboratory.

The students barely noticed him. Some may have wondered why someone so old would be wandering around a college campus. Others just tried not to plow him over as they rushed from building to building, attempting to get to their classes on time.

The old man was in fact a scientist visiting his laboratory to carry out experiments. The building bore his name.

One morning, he went to his lab to review the ongoing research he was contracted to do for the US government. When he arrived in front of door 118, he glanced in the direction of the nameplate on the wall next to it. Was he in the right place? His eyesight had failed greatly over the past decade, taking away his ability to focus clearly on the name. Fairly certain he stood in front of the correct room, he reached into a coat pocket, its trim worn and frayed. His thin, frail fingers searched for the key.

His hand shook as he grabbed ahold of it. His hand found the doorknob and located the keyhole; then he leaned down to see it better. He slid the key in, but it stopped short of complete entry. He jiggled the doorknob, hoping the key would drop into place. The key wouldn’t turn. He tried again. It still didn’t work. Perhaps he was on the wrong floor of the building. The old man moved a step to his left, directly in front of the nameplate and then leaned in for a closer look. Sure enough, the correct name was there. Concluding something was wrong with the key, he ambled out of the building and crossed the sun-soaked parking lot to the Ames Laboratory administration building. When he came through the door, the secretary sitting at the reception desk looked up and said, Hello, Dr. Wilhelm. What can I do for you?

Well, there’s something wrong with my key. It won’t open my office door.

Oh, she replied, the feds were here, and they changed the locks. No one is allowed in.

Befuddled, he asked, Why would they do that?

Your office and most of the building is radioactive. It’s not safe to be working in there, she explained.

He shook his head and, with incredulity in his voice, said, I’ve been working in that building for over forty years. It hasn’t killed me yet.

Part 1

No Pure Uranium,

No Atomic Bomb

Chapter 1

The Uranium Problem

It is clear that the problem of producing and purifying materials was a major one.

—H. D. Smyth, Atomic Energy for Military Purposes

On September 23, 1942, Dr. Harley Wilhelm rushed to the train station in downtown Ames, Iowa. As usual, he was running late. With only a few minutes to spare, he boarded the midnight train bound for Chicago. Along with his luggage he carried his trusty briefcase. Nestled inside was his secret cargo: something with the potential to bring about the end of World War II.

For the past several weeks, Wilhelm and his team at Iowa State College had worked arduously, day and night, to produce a sample. Transporting it across the central plains of the United States gave rise to inherent risks, to both his personal safety and the security of the nation. The timing of his trip was of vital importance to national security. For Wilhelm, the next day would bring a moment of truth: he would attempt to prove to others that he had solved the uranium problem.

Wilhelm found the sleeper car prepped and waiting for him. When he settled in for the night’s ride, he kept the package in bed with him. It was too valuable a commodity to stow away from his person. As the train coursed across the plains, Wilhelm tried to get some sleep.

Arthur Compton, the leader of the Metallurgical Laboratory for the Manhattan Project, was the intended recipient of Wilhelm’s package. Wilhelm claimed it contained pure uranium, but Compton was skeptical. Scientists had been trying to purify uranium since its discovery in 1789. More than one hundred fifty years later, virtually no progress had been made. Wilhelm’s assertion was nearly fantastical.

A Nobel laureate with heavy brow and deep-set eyes, Compton was the senior scientist managing the Plutonium Project, the original name given to the effort by the project scientists who worked on it. From his vantage point, Wilhelm’s remarkable claim was highly unlikely to be true. Wilhelm, a portly and friendly faced fellow, had only been working on the project for a short six months. He hadn’t earned any recognition or awards for his chemical and metallurgical research and was not well-known in the scientific community at large. Wilhelm and his small team of young scientists at Ames had no prior experience working with uranium, number 92 on the periodic table of elements. He hardly seemed the candidate who would solve Compton’s dilemma.

Compton had plans to conduct an experiment: a controlled and self-sustained nuclear chain reaction. It was scheduled to take place in Chicago on December 2, 1942, less than three months away. The experiment’s success depended on the acquisition of about twelve thousand pounds of pure uranium. Wilhelm believed he could produce a significant portion of the required amount, but uncertainty remained as to whether the total tonnage could be produced by anyone, by any means, in time to meet the December deadline.

A member of Compton’s team, Enrico Fermi, had made the calculations to determine the amount of pure uranium needed. Fermi was an Italian immigrant who’d arrived in America in January 1939 after collecting his Nobel Prize in Physics in Stockholm in December 1938. He had joined his homeland’s Fascist Party, for professional expediency rather than ideological reasons, but in 1938 his homeland passed the Italian Racial Laws, which endangered his wife, who was Jewish, and his children. He fled to America with his family out of fear for his safety and theirs.

Fermi led a team in Chicago and was responsible for designing the nuclear experiment for Compton. If the experiment proved fruitful, the possibility of the United States developing and assembling a new weapon, a super bomb, had the potential to go from theory to reality. President Roosevelt and his scientific consultants hoped that this super bomb—eventually renamed the atomic bomb—would bring a swift and definitive end to World War II.

Nuclear reactions, which involve the splitting of the nucleus of an atom in two (known as fission), had thus far only occurred in tests carried out in laboratory settings. Those experiments were conducted using minute quantities of uranium, often just a few micrograms, because obtaining larger quantities was, as yet, impossible. The amounts available were too small for any practical use in developing atomic weaponry.

The combination of scarcity and lack of purity posed a seemingly impregnable barrier to creating such a weapon. But if Compton’s team were to obtain enough pure uranium, they could test the theory that energy released during fission could unleash unfathomable power. If a chain reaction could be achieved and sustained, it would establish the foundational science for not only the first-ever atomic bomb, but also a new form of energy: thermonuclear.

In 1944 Henry Smyth, a physicist from Princeton University, was commissioned to write the government’s official and historical account of the project to build an atomic bomb. By embedding himself in the project he was able to interview scientists, military staff, and contracted industry partners as the project progressed. In his report, entitled Atomic Energy for Military Purposes (commonly referred to as the Smyth Report), Smyth laid out how the leaders of the project contended with monumental problems and overcame many obstacles. As he wrote,

The principle of operation of an atomic bomb or power plant utilizing uranium fission is simple enough. If one neutron causes a fission that produces more than one neutron, the number of fissions may increase tremendously with the release of major amounts of energy. It is a question of probabilities. Neutrons produced in the fission process may escape entirely from the uranium, may be captured by uranium in a process not resulting in fission, or may be captured in an impurity. Thus the question of whether a chain reaction does or does not go depends on the result of a competition among four processes: 1) escape, 2) non-fission capture by uranium, 3) non-fission capture by impurities, 4) fission capture.

Pure uranium is required for a sustained fission (nuclear) chain reaction. If impurities are present they will absorb too many of the free neutrons and kill the reaction.

Scientific discovery usually proceeds slowly. Performing vast amounts of research in a few short months was a massive undertaking and atypical to practical norms for conducting research. And, in science, as Compton and Fermi were well aware, there are no guarantees of getting the desired results.

Typically, years of painstaking trials are needed to ascertain results of significance and value. Up until this time, that truism had held constant for research on nuclear changes. Starting as far back as 1934, Fermi had been bombarding uranium with neutrons to induce nuclear changes, but the results had stymied both him and his colleagues.

During the war, however, expediency outweighed the demand for traditional research methods. Every day, new information was swiftly assessed and put to use to push the project forward. Supporting documentation was often lacking because time was of the essence. Documenting each step stole time away from the work.

In his report, Smyth emphasized that at the beginning of the project the team had lacked understanding of the basic chemistry of uranium. The shortfall of knowledge threatened to delay or even stall success. A longer war loomed.

During the final years of the nineteenth century and the first two decades of the twentieth, interest in uranium had grown among a small number of researchers. Though investigations into preparation methods had increased, no major advances had been made in uranium metal purification.

In the years leading up to the outbreak of the war, many fundamental studies on nuclear physics and nuclear chemistry were conducted across the country. The researchers, mostly working in university labs, had access only to funding they raised themselves from outside sources, over and above their normal operating budgets. Even though their research provided valuable insights, financial support was sparse.

However, in the months leading up to the attack on Pearl Harbor, when it became apparent that uranium was the best choice to fuel a self-sustained nuclear chain reaction, more experimentation to advance the understanding of uranium emerged in academia and industry. With the support of Vannevar Bush, limited funding had become available to a few select universities.

Decades later, in his 1960 report to the US Atomic Energy Commission, Wilhelm noted that many reinvestigations had been done to corroborate results of previously reported methods for preparing uranium. When recounting his time on the project, Wilhelm acknowledged that the earlier work indirectly contributed to the early success of the uranium metal phase of the Manhattan Project. Though researchers had increased their knowledge, Wilhelm and others lamented the fact that results from different researchers’ experiments were often conflicted, creating serious gaps in the understanding of nuclear physics and its related chemistries.

While scientists typically publish the results of their work, there was no coordinated administration or communication during the research phase. As war work ramped up, this became a major drawback. Researchers in different academic laboratories were unaware of each other’s work. In industry, a number of companies opted to launch their own autonomous studies, hoping to profit if the United States entered the war. Collaboration and cooperation between academia and industrial laboratories were essentially nonexistent.

The absence of coordination was exacerbated by the limited supply of uranium. Prior to 1942, due to the complexities of a suitable purification process, only a few grams of not-quite-pure uranium were known to exist. Although it wasn’t pure, researchers begged for access to it. Even small amounts of rare earth elements and related supplies were often loaned by one laboratory to another.

A monumental shift occurred the day Vannevar Bush, the head of the Office of Scientific Research and Development (OSRD), and James B. Conant, the chairman of the National Defense Research Committee (NDRC), agreed to let Compton form a secret team to develop the atomic bomb. The S-1 Committee, short for Section 1 of the OSRD, would coordinate research to investigate the feasibility of building an atomic weapon. The meeting between Bush, Conant, and Compton on December 6, 1941, less than twenty-four hours before the attack on Pearl Harbor, unleashed the capabilities of the National Defense Research Committee, allowing it to begin extensive coordination between industry, academia, and government in an all-out effort to develop an atomic bomb. Though the committee had the full support of President Roosevelt, it wasn’t until after the attack on Pearl Harbor that formal funding, outside the president’s slush fund, was deemed warranted. With that a fully coordinated effort by the US government was finally put into motion.

Within a matter of days after the attack Compton was given funding to set up teams of researchers around the country. Major research programs were established at three prominent universities: Columbia University, the University of California, and the University of Chicago. Princeton and the National Bureau of Standards also had research well underway.

In his report, Smyth detailed how metallurgical research contributed to the successful culmination of the Manhattan Project. Complex problems were solved. New methods were created. Timelines were shortened. And costs were cut.

But as this considerable scientific force mobilized for Compton’s project, the most pressing issue remained the uranium problem.

Chapter 2

A Change in Life’s Trajectory

The battle of the laboratories held fateful risks for us as well as the battles of the air, land and sea.

—Harry S. Truman, Statement by the President Announcing the Use of the A-Bomb at Hiroshima, August 6, 1945

Wilhelm’s trip to Chicago came at the end of a stressful summer. Hostilities in Europe for over two years had torn countries and families apart. The war was expanding, and there was no end in sight. Every day more young Americans were being drafted and shipped overseas. By September 1942, thousands had already died. This weighed heavily on Wilhelm. He had a fourteen-year-old son; if the war were to drag on for several more years, Max could be drafted.

Toiling away on little sleep, Wilhelm sometimes spent twenty-four hours of the day in his laboratory. Since he’d been assigned the project by his boss, Frank Spedding, the head of the Physical Chemistry department at Iowa State, the intense work had gone on for months.

In February 1942 Spedding had received a call from Compton asking if he would be interested in joining a highly classified project that would aid in the war effort. When Spedding answered yes, Compton asked him to come to Chicago to meet with the team he’d assembled there.

Earlier that month, Compton had conducted several meetings with his handpicked team of scientific advisers, mostly physicists. They reviewed the plethora of challenges to be overcome before the project could succeed. As they met, it became increasingly apparent that it was necessary to find a chemist who could work out the complex chemical analysis needed for the project.

Then, in late February, Spedding arrived and met the team. All of them, if not currently luminaries in their fields, soon would be: Enrico Fermi, Leo Szilard, Samuel Allison, John A. Wheeler, Richard L. Doan, Herbert McCoy, Gregory Breit, Ernest Thiele, and future Nobel laureates John H. Van Vleck and Eugene Wigner. Over the two days of discussions it became ever more apparent that they needed a uniquely qualified chemist—specifically a metallurgist with the ingenuity and resolve to remove the roadblocks of uranium extraction and purification.

On December 11, 1941, just four days after Japan bombed Pearl Harbor, the United States and Germany declared war against each other.

By December 13 Bush had sent a letter to Compton in which he outlined his plans for the secret project to develop a nuclear weapon. Bush had decided to hire three program chiefs to manage various facets of the project; Compton was one of them. Compton’s responsibilities encompassed the advancement of weapons theory and leading the efforts for the chain reaction development using uranium-235 and the production of plutonium. Bush put Harold Urey of Columbia University in charge of separation and diffusion methods for separating isotopes and the study of heavy water. The other appointee, Ernest Lawrence of the University of California, Berkeley, was charged with small sample preparation, electromagnetic separation methods, and experimentation on plutonium. With multiple tasks at hand, these three men were heading down different paths of a journey to discover which method would be most viable for producing ultrapure uranium and, ultimately, plutonium.

Uranium (symbol U) is a radioactive silvery-gray metal. Made up of ninety-two protons and ninety-two electrons (hence its assigned number and placement on the periodic table of elements), uranium naturally occurs in the form of one of three isotopes: U-234, U-235, and U-238. U-238 is the most prevalent isotope, at over 99 percent of naturally occurring uranium, while U-235 is approximately .7 percent and U-234 is negligible. Of the three, U-235 is the only isotope that is fissile and thus was needed in large quantities to build the first atomic bomb, Little Boy. First it had to be refined from its ore into compounds and then purified to remove other elements, molecules, and impurities. After purification came enrichment, or separation of U-235 from the other isotopes, in order to obtain the quantity needed.

Plutonium, number 94 on the periodic table of elements, was used to build the second atomic bomb, known as Fat Man. Because plutonium is essentially nonexistent in nature, it needed to be manufactured. While uranium in the form of U-238 is nonfissile (incapable of sustaining a nuclear reaction), it was believed to be fissionable, meaning that a nuclear reactor could transmute it to plutonium. The abundance of U-238 also made it a practical choice for use in the plan to manufacture plutonium.

After receiving Bush’s letter, Compton immediately began putting together a highly talented team of scientists and invited them to a two-day conference in Chicago. He hoped they could brainstorm and vet processes that would break through the known barriers to achieving a nuclear chain reaction.

Compton code-named the meeting Conference on Power Plant to make it appear as though they would be discussing methods of producing energy. A smokescreen was compulsory. They couldn’t risk the enemy learning of the US plan to develop an atomic weapon.

The link between Compton and Spedding ran through Herbert McCoy. Spedding first encountered McCoy in 1933 at the Chicago World’s Fair. Spedding described him as a short fellow, like Santa Claus, and he was indeed a generous sort. McCoy attended Spedding’s acceptance speech of an award bestowed on him at the fair, and he noted Spedding’s deep interest in rare earth metals. So McCoy ambled up to the stage and loudly asked him, How would you like to have a pound of europium and two or three pounds of samarium?

Samarium and europium are so rare that Spedding thought the offer was a joke. As far as he knew, the elements were nowhere to be found, especially in the quantities that McCoy was offering. Spedding later remarked to people that he thought the guy was crazy. Nonetheless, Spedding, in an offhanded manner, told McCoy he’d take them. At the University of California, Berkeley, laboratory where he worked, he knew those particular rare earth metals would be helpful.

Spedding asked around and learned that McCoy was a vice president at the Lindsay Light and Chemical Company. The company had excess residues of these two elements as a result of separation processes they used on other elements. McCoy was willing to provide these metals to people he believed merited access to them.

Spedding headed back home to California and his laboratory, fully expecting that was the last he would hear of the offer. Much to his grateful surprise, shortly after his return home a package arrived, filled with fruit jars containing europium and samarium oxides. Spedding and McCoy eventually became friends.

Now, in 1942, as Compton started asking his chemist friends for the name of an inorganic chemist who had worked with the rare earth elements and, in particular, uranium, he turned to McCoy, who was his former colleague at the University of Chicago. Compton wanted him to lead the chemistry work for the project, but McCoy wasn’t interested (although he would ably conduct some work for the project at Compton’s request). Instead, McCoy recommended Spedding, who had since taken a position at Iowa State College and had the necessary expertise.

Compton’s invitation was the call to duty Spedding had long hoped for. He alone went to Chicago, leaving Wilhelm in Ames to cover the physical chemistry classes he usually taught. The impromptu trip to Chicago surprised Wilhelm because no professional or academic conferences in their fields of study were being held at the time. Did Spedding tell Wilhelm whom he was meeting with and why? Wilhelm likely could have surmised the topics to be discussed and their magnitude, especially given the list of attendees. But if he knew, he never let on to that fact. He and other scientists knew, of course, of the discovery of fission by Lise Meitner and Otto Frisch in Germany in 1939, but as far as anyone knew, the United States wasn’t working on building an atomic bomb. If the theory of a nuclear chain reaction were to be proved out by the Germans, however, it could lead to devastating results for the Allies.

Over the course of the two days of meetings in Chicago, thorough discussions ensued on the problems to be solved and their possible solutions. In addition, the group decided a code name was needed for their team and effort. Before the US entry into the war, conversations about building a metallurgical laboratory had taken place among university officials. The code name Metallurgical Laboratory made this highly classified effort sound like a normal operating department of the university. The project could be hidden in plain sight.

Compton planned to build a team in Chicago whose work would focus on the chemistry of uranium and plutonium; each member of the team would be assigned specific challenges to resolve. But items vital to fulfilling the mission—equipment, supplies, and people—had yet to be put in place.

Spedding was asked to run