Book Review: The Making of the Atomic Bomb

The Making of the Atomic Bomb
by Richard Rhodes
Simon & Schuster, 1986.

Five years in the writing, Richard Rhodes' history of the atomic bomb has become a landmark in the field of science popularization. At over 900 pages long, the book is very comprehensive in its recounting of the events that led to the most terrible weapon ever devised by man. It is really several different books in one, shifting in tone and emphasis as it follows the concept from start to finish: from scientific discovery to military-industrial project to the study of political decision-making in war.

Scientific discovery

The first third of the book is largely an account of scientific discovery, as experimenters worked to uncover the structure of the atom at the turn of the 20th century. Even in this foundational period, it was easy to see that nuclear bombardment involved energies that were orders of magnitude greater than the chemical reactions already familiar to science. It was natural to speculate about how to unlock those energies someday, and thus the dream of nuclear energy developed right alongside the earliest experiments. Frederick Soddy described the possibility of nuclear energy in his book The Interpretation of Radium (1909), based on his work alongside Ernst Rutherford. H. G. Wells then picked up on the idea in his famous novel The World Set Free (1914).

But the early nuclear bombardments could only play with atomic forces at a small scale. With the discovery of nuclear fission, it became obvious that a chain reaction was possible and could be used to multiply the energies released. But it would not be worked out in a time of peace on earth and brotherhood among men. With the expulsion of Jewish academics from German universities and the looming onset of World War II, the leading lights of atomic science left Europe for America. In just a few years, the center of gravity in the physics world had shifted across the Atlantic.

Fast track from Research to Development

A mere seven years separated the discovery of nuclear fission from the first atomic bomb, a startlingly short period of time even by comparison to today's accelerated lab-to-market cycles. The young field of nuclear science picked up its terminology from other sciences. The term “fission” was borrowed from cell biology. Atomic “piles” became “reactors” when the chemical giant du Pont got involved in the project. Interestingly, du Pont was so worried about being labeled a war profiteer that it did the project for cost plus $1. Yes, it was a different time indeed.

Even as the Manhattan Project was steaming full-speed ahead, the physicists continued working on theory. Concepts for the hydrogen bomb were being proposed as early as 1942! Of course, there would be no time to pursue those H-bomb concepts until the atomic bomb effort had been completed. But from the perspective of atomic physics, it was not wide-eyed dreaming. The hydrogen bomb was simply a matter of following scientific principles to their logical conclusion.

Rhodes is very skilled at presenting technical concepts clearly and exploring salient details. For example, there was not enough uranium being produced from the isotope-separation plants to “waste” some on a test explosion. Thus, the gun-type uranium bomb was dropped on Hiroshima without ever having been tested. How could they be so confident that their calculations had not neglected some factor? What if the bomb had fizzled?

Actually, they had tested their calculations in a series of daring “tickling the dragon” experiments. A small chunk of uranium hydride was dropped through a larger donut, briefly creating a critical mass and allowing the scientists to verify the precursor to a nuclear explosion. The hydride slowed the reaction enough that it would not explode during the brief moment of criticality. Talk about betting your life on the laws of physics! This definitely has Walter Lewin beat. The experiment was then dismantled, the uranium was recovered from the hydride — and the very same atoms of uranium would be the ones that got dropped on Hiroshima.

Astonishing scale

The Manhattan Project was enormous in scale. Rhodes puts it at the rough equivalent of building the entire American automobile industry from scratch in just a few years. In a total war in which the future of human civilization hung in the balance, time was more important than money. Some of the production techniques adopted for the Manhattan Project would be the work of a madman in peacetime.

For example, in the spirit of going all-in on the war effort, the United States Treasury had offered to loan out the silver in its vaults for any recoverable purpose. The Manhattan Project took them up on that offer for the electromagnetic uranium separation facility being built at Oak Ridge. The atomic engineers borrowed tons of silver from a Treasury that was more accustomed to dealing in ounces. What did they need the silver for? Because copper was in critically short supply. Precious metals would be worthless to the United States if it couldn't win the war, and thus it became worthwhile to build factory machinery with silver wiring. Silver happens to be a better conductor than copper, and so it reduced the resistance losses in the electricity-intensive process. Eventually, the silver was melted down and returned to the Treasury.

In another example, the uranium diffusion plant had run seriously behind schedule using the Norris-Adler barrier. The only way to rescue the uranium bomb (and avoid depending solely on the plutonium weapon) was to convert to the Kellex barrier. But there wasn't enough time to tool up a factory to produce the new barriers. What did they do instead? Thousands of workers assembled the Kellex barriers manually, by piecework. In other words, they didn't bother to scale up from the lab bench to an industrial process — instead, they just duplicated the lab bench thousands of times.

Conclusion

Rhodes began writing the book in 1981, roughly around the time when public concern over nuclear winter was at a maximum. It was only a couple of years prior that the basic concept behind the Teller-Ulam hydrogen bomb had finally been declassified. There is thus some urgency in the editorial commentary that we do not feel in today's post-Cold War world.

When describing the effects of the bomb on Hiroshima, Rhodes decides not to do it. Instead, he simply prints pages of verbatim recollections from the survivors. The stark and immediate first-hand accounts remind us of the terror of nuclear war. No matter how peaceful the world has become, the specter of the Bomb will forever hang over us. An awesome weapon has been invented, and it cannot be un-invented.